記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41598-018-24749-6

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1152/ajpheart.00329.2018

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Verlag  

Sympathetic activation causes clinically important arrhythmias including atrial fibrillation (AF) and ventricular tachyarrhythmia. Although the usefulness of β-adrenergic receptor blockade therapy is widely accepted, its multiple critical side effects often prevent its initiation or continuation. The aim of this study is to determine the advantages of vidarabine, an adenylyl cyclase (AC)-targeted anti-sympathetic agent, as an alternative treatment for arrhythmia. We found that vidarabine, which we identified as a cardiac AC inhibitor, consistently shortens AF duration and reduces the incidence of sympathetic activation-induced ventricular arrhythmias. In atrial and ventricular myocytes, vidarabine inhibits adrenergic receptor stimulation-induced RyR2 phosphorylation, sarcoplasmic reticulum (SR) Ca2+ leakage, and spontaneous Ca2+ release from SR, the last of which has been considered as a potential arrhythmogenic trigger. Moreover, vidarabine also inhibits sympathetic activation-induced reactive oxygen species (ROS) production in cardiac myocytes. The pivotal role of vidarabine’s inhibitory effect on ROS production with regard to its anti-arrhythmic property has also been implied in animal studies. In addition, as expected, vidarabine exerts an inhibitory effect on AC function, which is more potent in the heart than elsewhere. Indexes of cardiac function including ejection fraction and heart rate were not affected by a dosage of vidarabine sufficient to exert an anti-arrhythmic effect. These findings suggest that vidarabine inhibits catecholamine-induced AF or ventricular arrhythmia without deteriorating cardiac function in mice.

DOI： 10.1007/s00424-018-2121-4

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Impact Journals LLC  

N,N'-Bis(salicylidene)ethylenediamine iron (Fe(Salen)) is an anti-cancer agent with intrinsic magnetic property. Here, we covalently linked Fe(Salen) to paclitaxel (PTX), a widely used anti-cancer drug, to obtain a magnetized paclitaxel conjugate (M-PTX), which exhibited magnetic characteristics for magnet-guided drug delivery and MRI visualization. M-PTX increased apoptosis and G2/M arrest of cultured human oral cancer cell lines in the same manner as PTX. Furthermore, marked contrast intensity was obtained in magnetic resonance imaging (MRI) of M-PTX. In a mouse oral cancer model, a permanent magnet placed on the body surface adjacent to the tumor resulted in distinct accumulation of M-PTX, and the anti-cancer effect was greater than that of M-PTX without the magnet. We believe that this strategy may improve future cancer chemotherapy by providing conventional anti-cancer drugs with novel functionalities such as magnet-guided drug delivery or MRI-based visualization/ quantitation of drug distribution.

DOI： 10.18632/oncotarget.24570

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1172/jci.insight.90903

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Shortage of autologous blood vessel sources and disadvantages of synthetic grafts have increased interest in the development of tissue-engineered vascular grafts. However, tunica media, which comprises layered elastic laminae, largely determines arterial elasticity, and is difficult to synthesize. Here, we describe a method for fabrication of arterial grafts with elastic layer structure from cultured human vascular SMCs by periodic exposure to extremely high hydrostatic pressure (HP) during repeated cell seeding. Repeated slow cycles (0.002 Hz) between 110 and 180 kPa increased stress-fiber polymerization and fibronectin fibrillogenesis on SMCs, which is required for elastic fiber formation. To fabricate arterial grafts, seeding of rat vascular SMCs and exposure to the periodic HP were repeated alternatively ten times. The obtained medial grafts were highly elastic and tensile rupture strength was 1451 +/- 159 mmHg, in which elastic fibers were abundantly formed. The patch medial grafts were sutured at the rat aorta and found to be completely patent and endothelialized after 2.5 months, although tubular medial constructs implanted in rats as interpositional aortic grafts withstood arterial blood pressure only in early acute phase. This novel organized self-assembly method would enable mass production of scaffold-free arterial grafts in vitro and have potential therapeutic applications for cardiovascular diseases.

DOI： 10.1038/s41598-017-00237-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Nanoparticulate agents for magnetic drug delivery systems (DDSs) have extensive applications in targeted drug delivery, contrast imaging and therapeutics. However, no simple synthetic method for magnetic DDS agents has been developed without the need to add magnetic nanoparticles. Here, we describe the one-step fabrication of 'all-in-one' magneto-assemblies using an 'inorganic-metal-salt-free' method, involving spontaneous self-assembly of the water-insoluble prodrug mu-oxo-bis(N, N'-ethylenebis (salicylideniminato) iron) [Fe(salen)] (magnetic core) with polypyrrole (PPy)-b-polycaprolactone (PCL) smart diblock copolymers. In the system, PCL serves as a heat-responsive core scaffold, and PPy serves as an electronic core-size controller and pH-responsive shell. This core-shell nanocomposite has a high-loading capacity (similar to 90%), and the core size is tunable by incorporating albumin or gum arabic as bio-coating agents, which also provide colloidal stability, biocompatibility and thermo-stability. Fe(salen), which has intrinsic antitumor activity, also has ubiquitous magnetic properties, which are dramatically enhanced in these molecular assemblies with magnetic coupling. Moreover, these multifunctional nanoassemblies can be delivered magnetically, can serve as magnetic resonance imaging contrast agents, can generate magneto-hyperthermal effects and can enable magnetic field-triggered release of Fe(salen) molecules under acidic conditions.

DOI： 10.1038/am.2017.29

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

We previously reported that mu-oxo N, N'-bis(salicylidene) ethylenediamine iron [Fe(Salen)], a magnetic organic compound, has direct anti-tumor activity, and generates heat in an alternating magnetic field (AMF). We showed that Fe(Salen) nanoparticles are useful for combined hyperthermia-chemotherapy of tongue cancer. Here, we have examined the effect of Fe(Salen) on human glioblastoma (GB). Fe(Salen) showed in vitro anti-tumor activity towards several human GB cell lines. It inhibited cell proliferation, and its apoptosis-inducing activity was greater than that of clinically used drugs. Fe(Salen) also showed in vivo anti-tumor activity in the mouse brain. We evaluated the drug distribution and systemic side effects of intracerebrally injected Fe(Salen) nanoparticles in rats. Further, to examine whether hyperthermia, which was induced by exposing Fe(Salen) nanoparticles to AMF, enhanced the intrinsic anti-tumor effect of Fe(Salen), we used a mouse model grafted with U251 cells on the left leg. Fe(Salen), BCNU, or normal saline was injected into the tumor in the presence or absence of AMF exposure. The combination of Fe(Salen) injection and AMF exposure showed a greater anti-tumor effect than did either Fe(Salen) or BCNU alone. Our results indicate that hyperthermia and chemotherapy with single-drug nanoparticles could be done for GB treatment.

DOI： 10.1038/srep42783

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記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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その他リンク： http://orcid.org/0000-0001-8006-5485

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

We previously investigated the utility of mu-oxo N,N'-bis(salicylidene) ethylenediamine iron (Fe(Salen)) nanoparticles as a new anti-cancer agent for magnet-guided delivery with anti-cancer activity. Fe(Salen) nanoparticles should rapidly heat up in an alternating magnetic field (AMF), and we hypothesized that these single-drug nanoparticles would be effective for combined hyperthermia-chemotherapy. Conventional hyperthermic particles are usually made of iron oxide, and thus cannot exhibit anticancer activity in the absence of an AMF. We found that Fe(Salen) nanoparticles induced apoptosis in cultured cancer cells, and that AMF exposure enhanced the apoptotic effect. Therefore, we evaluated the combined three-fold strategy, i.e., chemotherapy with Fe(Salen) nanoparticles, magnetically guided delivery of the nanoparticles to the tumor, and AMF-induced heating of the nanoparticles to induce local hyperthermia, in a rabbit model of tongue cancer. Intravenous administration of Fe(Salen) nanoparticles per se inhibited tumor growth before the other two modalities were applied. This inhibition was enhanced when a magnet was used to accumulate Fe(Salen) nanoparticles at the tongue. When an AMF was further applied (magnet-guided chemotherapy plus hyperthermia), the tumor masses were dramatically reduced. These results indicate that our strategy of combined hyperthermia-chemotherapy using Fe(Salen) nanoparticles specifically delivered with magnetic guidance represents a powerful new approach for cancer treatment.

DOI： 10.1038/srep24629

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

Nanomaterials have been widely used for applications in biomedical fields and could become indispensable in the near future. However, since it is difficult to optimize invivo biological behavior in a 3D environment by using a single cell invitro, there have been many failures in animal models. Invitro prediction systems using 3D human-tissue models reflecting the 3D location of cell types may be useful to better understand the biological characteristics of nanomaterials for optimization of their function. Herein we demonstrate the potential ability of 3D engineered human-arterial models for invitro prediction of the invivo behavior of nanoparticles for drug delivery. These models enabled optimization of the composition and size of the nanoparticles for targeting and treatment efficacy for atherosclerosis. Invivo experiments with atherosclerotic mice suggested excellent biological characteristics and potential treatment effects of the nanoparticles optimized in vitro.

DOI： 10.1002/anie.201509752

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DOI： 10.1152/ajpheart.00411.2015

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Objective Vascular smooth muscle cell (SMC) migration causes neointima, which is related to vascular remodeling after mechanical injury and atherosclerosis development. We previously reported that an exchange protein activated by cAMP (Epac) 1 was upregulated in mouse arterial neointima and promoted SMC migration. In this study, we examined the molecular mechanisms of Epac1-induced SMC migration and the effect of Epac1 deficiency on vascular remodeling in vivo.
Approach and Results Platelet-derived growth factor-BB promoted a 2-fold increase in SMC migration in a primary culture of aortic SMCs obtained from Epac1(+/+) mice (Epac1(+/+)-ASMCs), whereas there was only a 1.2-fold increase in Epac1(-/-)-ASMCs. The degree of platelet-derived growth factor-BB-induced increase in intracellular Ca2+ was smaller in Fura2-labeled Epac1(-/-)-ASMCs than in Epac1(+/+)-ASMCs. In Epac1(+/+)-ASMCs, an Epac-selective cAMP analog or platelet-derived growth factor-BB increased lamellipodia accompanied by cofilin dephosphorylation, which is induced by Ca2+ signaling, whereas these effects were rarely observed in Epac1(-/-)-ASMCs. Furthermore, 4 weeks after femoral artery injury, prominent neointima were formed in Epac1(+/+) mice, whereas neointima formation was significantly attenuated in Epac1(-/-) mice in which dephosphorylation of cofilin was inhibited. The chimeric mice generated by bone marrow cell transplantation from Epac1(+/+) into Epac1(-/-) mice and vice versa demonstrated that the genetic background of vascular tissues, including SMCs rather than of bone marrow-derived cells affected Epac1-mediated neointima formation.
Conclusions These data suggest that Epac1 deficiency attenuates neointima formation through, at least in part, inhibition of SMC migration, in which a decrease in Ca2+ influx and a suppression of cofilin-mediated lamellipodia formation occur.

DOI： 10.1161/ATVBAHA.115.306534

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Research on controlled drug delivery for cancer chemotherapy has focused mainly on ways to deliver existing anti-cancer drug compounds to specified targets, e.g., by conjugating them with magnetic particles or encapsulating them in micelles. Here, we show that an iron-salen, i.e., mu-oxo N, N'bis( salicylidene) ethylenediamine iron (Fe(Salen)), but not other metal salen derivatives, intrinsically exhibits both magnetic character and anti-cancer activity. X-Ray crystallographic analysis and first principles calculations based on the measured structure support this. It promoted apoptosis of various cancer cell lines, likely, via production of reactive oxygen species. In mouse leg tumor and tail melanoma models, Fe(Salen) delivery with magnet caused a robust decrease in tumor size, and the accumulation of Fe(Salen) was visualized by magnetic resonance imaging. Fe(Salen) is an anti-cancer compound with magnetic property, which is suitable for drug delivery and imaging. We believe such magnetic anti-cancer drugs have the potential to greatly advance cancer chemotherapy for new theranostics and drug-delivery strategies.

DOI： 10.1038/srep09194

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Angiotensin II type 1 receptor (AT1R)-associated protein (ATRAP) promotes AT1R internalization along with suppression of pathological activation of tissue AT1R signaling. However, the functional significance of ATRAP in renal sodium handling and blood pressure regulation under pathological stimuli is not fully resolved. Here we show the blood pressure of mice with a gene-targeted disruption of ATRAP was comparable to that of wild-type mice at baseline. However, in ATRAP-knockout mice, angiotensin II-induced hypertension was exacerbated and the extent of positive sodium balance was increased by angiotensin II. Renal expression of the sodium-proton antiporter 3, a major sodium transporter in the proximal tubules, urinary pH, renal angiotensinogen production, and angiotensin II content was unaffected. Stimulation of the renal expression and activity of the epithelial sodium channel (ENaC), a major sodium transporter in the distal tubules, was significantly enhanced by chronic angiotensin II infusion. The circulating and urinary aldosterone levels were comparable. The blood pressure response and renal ENaC expression by aldosterone were not affected. Thus, ATRAP deficiency exacerbated angiotensin II-mediated hypertension by pathological activation of renal tubular AT1R by angiotensin II. This directly stimulates ENaC in the distal tubules and enhances sodium retention in an aldosterone-independent manner.

DOI： 10.1038/ki.2014.95

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Fibroblast growth factor (FGF2) regulates endothelial and melanoma cell migration. The binding of FGF2 to its receptor requires N-sulfated heparan sulfate (HS) glycosamine. We have previously reported that Epac1, an exchange protein activated by cAMP, increases N-sulfation of HS in melanoma. Therefore, we examined whether Epac1 regulates FGF2-mediated cell-cell communication. Conditioned medium (CM) of melanoma cells with abundant expression of Epac1 increased migration of human umbilical endothelial cells (HUVEC) and melanoma cells with poor expression of Epac1. CM-induced increase in migration was inhibited by antagonizing FGF2, by the removal of HS and by the knockdown of Epac1. In addition, knockdown of Epac1 suppressed the binding of FGF2 to FGF receptor in HUVEC, and in vivo angiogenesis in melanoma. Furthermore, knockdown of Epac1 reduced N-sulfation of HS chains attached to perlecan, a major secreted type of HS proteoglycan that mediates the binding of FGF2 to FGF receptor. These data suggested that Epac1 in melanoma cells regulates melanoma progression via the HS-FGF2-mediated cell-cell communication.

DOI： 10.1111/pcmr.12250

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC CLINICAL INVESTIGATION INC  

PKA phosphorylates multiple molecules involved in calcium (Ca2+) handling in cardiac myocytes and is considered to be the predominant regulator of beta-adrenergic receptor-mediated enhancement of cardiac contractility; however, recent identification of exchange protein activated by cAMP (EPAC), which is independently activated by cAMP, has challenged this paradigm. Mice lacking Epac1 (Epac1 KO) exhibited decreased cardiac contractility with reduced phospholamban (PLN) phosphorylation at serine-16, the major PKA-mediated phosphorylation site. In Epac1 KO mice, intracellular Ca2+ storage and the magnitude of Ca2+ movement were decreased; however, PKA expression remained unchanged, and activation of PICA with isoproterenol improved cardiac contractility. In contrast, direct activation of EPAC in cardiomyocytes led to increased PLN phosphorylation at serine-16, which was dependent on PLC and PKC epsilon. Importantly, Epac1 deletion protected the heart from various stresses, while Epac2 deletion was not protective. Compared with WT mice, aortic banding induced a similar degree of cardiac hypertrophy in Epac1 KO; however, lack of Epac1 prevented subsequent cardiac dysfunction as a result of decreased cardiac myocyte apoptosis and fibrosis. Similarly, Epac1 KO animals showed resistance to isoproterenol- and aging-induced cardiomyopathy and attenuation of arrhythmogenic activity. These data support Epac1 as an important regulator of PKA-independent PLN phosphorylation and indicate that Epac1 regulates cardiac responsiveness to various stresses.

DOI： 10.1172/JCI64784

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

DOI： 10.1161/CIRCULATIONAHA.113.004726

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記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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その他リンク： http://orcid.org/0000-0001-8006-5485

出版者・発行元：1  

DOI： 10.1152/ajpheart.00080.2013

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記述言語：英語   出版者・発行元：AMER SOC PHARMACOLOGY EXPERIMENTAL THERAPEUTICS  

The EP4 prostanoid receptor is one of four receptor subtypes for prostaglandin E-2. It belongs to the family of G protein-coupled receptors. It was originally identified, similar to the EP2 receptor as a G(s)alpha-coupled, adenylyl cyclase-stimulating receptor. EP4 signaling plays a variety of roles through cAMP effectors, i.e., protein kinase A and exchange protein activated by cAMP. However, emerging evidence from studies using pharmacological approaches and genetically modified mice suggests that EP4, unlike EP2, can also be coupled to G(i)alpha, phosphatidylinositol 3-kinase, beta-arrestin, or beta-catenin. These signaling pathways constitute unique roles for the EP4 receptor. EP4 is widely distributed in the body and thus plays various physiologic and pathophysiologic roles. In particular, EP4 signaling is closely related to carcinogenesis, cardiac hypertrophy, vasodilation, vascular remodeling, bone remodeling, gastrointestinal homeostasis, renal function, and female reproductive function. In addition to the classic anti-inflammatory action of EP4 on mononuclear cells and T cells, recent evidence has shown that EP4 signaling contributes to proinflammatory action as well. The aim of this review is to present current findings on the biologic functions of the EP4 receptor. In particular, we will discuss its diversity from the standpoint of EP4-mediated signaling.

DOI： 10.1124/pr.112.007195

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Background-For reasons that remain unclear, whether type 5 adenylyl cyclase (AC5), 1 of 2 major AC isoforms in heart, is protective or deleterious in response to cardiac stress is controversial. To reconcile this controversy we examined the cardiomyopathy induced by chronic isoproterenol in AC5 transgenic (Tg) mice and the signaling mechanisms involved.
Methods and Results-Chronic isoproterenol increased oxidative stress and induced more severe cardiomyopathy in AC5 Tg, as left ventricular ejection fraction fell 1.9-fold more than wild type, along with greater left ventricular dilation and increased fibrosis, apoptosis, and hypertrophy. Oxidative stress induced by chronic isoproterenol, detected by 8-OhDG was 15% greater, P=0.007, in AC5 Tg hearts, whereas protein expression of manganese superoxide dismutase (MnSOD) was reduced by 38%, indicating that the susceptibility of AC5 Tg to cardiomyopathy may be attributable to decreased MnSOD expression. Consistent with this, susceptibility of the AC5 Tg to cardiomyopathy was suppressed by overexpression of MnSOD, whereas protection afforded by the AC5 knockout (KO) was lost in AC5 KOxMnSOD heterozyous KO mice. Elevation of MnSOD was eliminated by both sirtuin and MEK inhibitors, suggesting both the SIRT1/FoxO3a and MEK/ERK pathway are involved in MnSOD regulation by AC5.
Conclusions-Overexpression of AC5 exacerbates the cardiomyopathy induced by chronic catecholamine stress by altering regulation of SIRT1/FoxO3a, MEK/ERK, and MnSOD, resulting in oxidative stress intolerance, thereby shedding light on new approaches for treatment of heart failure. (Circulation. 2013; 127:1692-1701.)

DOI： 10.1161/CIRCULATIONAHA.112.001212

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1158/1538-7445.AM2013-5570

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Otsu K, Toya Y, Oshikawa J, Kurotani R, Yazawa T, Sato M, Yokoyama U, Umemura S, Minamisawa S, Okumura S, Ishikawa Y. Caveolin gene transfer improves glucose metabolism in diabetic mice. Am J Physiol Cell Physiol 298: C450-C456, 2010. First published November 18, 2009; doi: 10.1152/ajpcell.00077.2009. Caveolin, a member of the membrane-anchoring protein family, accumulates various growth receptors in caveolae and inhibits their function. Upregulation of caveolin attenuates cellular proliferation and growth. However, the role of caveolin in regulating insulin signals remains controversial. Here, we demonstrate that caveolin potently enhances insulin receptor (IR) signaling when overexpressed in the liver in vivo. Adenovirus-mediated gene transfer was used to overexpress caveolin specifically in the liver of diabetic obese mice, which were generated with a high-fat diet. Expression of molecules involved in IR signaling, such as IR or Akt, remained unchanged after gene transfer. However, hepatic glycogen synthesis was markedly increased with a decrease in phosphoenolpyruvate carboxykinase protein expression. Insulin sensitivity was increased after caveolin gene transfer as determined by decreased blood glucose levels in response to insulin injection and fasting blood glucose levels. Glucose tolerant test performance was also improved. Similar improvements were obtained in KKAy genetically diabetic mice. Adenovirus-mediated overexpression of caveolin-3 in hepatic cells also enhanced IR signaling, as shown by increased phosphorylation of IR in response to insulin stimulation and higher glycogen synthesis at baseline. These effects were attributed mostly to increased insulin receptor activity and caveolin-mediated, direct inhibition of protein tyrosine phosphatase 1B, which was increased in obese mouse livers. In conclusion, our results suggest that caveolin is an important regulator of glucose metabolism that can enhance insulin signals.

DOI： 10.1152/ajpcell.00077.2009

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記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Ischemic injury of the heart is associated with activation of multiple signal transduction systems including the heterotrimeric G-protein system. Here, we report a role of the ischemia-inducible regulator of G beta gamma subunit, AGS8, in survival of cardiomyocytes under hypoxia. Cultured rat neonatal cardiomyocytes (NCM) were exposed to hypoxia or hypoxia/reoxygenation following transfection of AGS8siRNA or pcDNA::AGS8. Hypoxia-induced apoptosis of NCM was completely blocked by AGS8siRNA, whereas overexpression of AGS8 increased apoptosis. AGS8 formed complexes with G-proteins and channel protein connexin 43 (CX43), which regulates the permeability of small molecules under hypoxic stress. AGS8 initiated CX43 phosphorylation in a G beta gamma-dependent manner by providing a scaffold composed of G beta gamma and CX43. AGS8siRNA blocked internalization of CX43 following exposure of NCM to repetitive hypoxia; however it did not influence epidermal growth factor-mediated internalization of CX43. The decreased dye flux through CX43 that occurred with hypoxic stress was also prevented by AGS8siRNA. Interestingly, the G beta gamma inhibitor Gallein mimicked the effect of AGS8 knockdown on both the CX43 internalization and the changes in cell permeability elicited by hypoxic stress. These data indicate that AGS8 is required for hypoxia-induced apoptosis of NCM, and that AGS8-G beta gamma signal input increased the sensitivity of cells to hypoxic stress by influencing CX43 regulation and associated cell permeability. Under hypoxic stress, this unrecognized response program plays a critical role in the fate of NCM.

DOI： 10.1074/jbc.M109.014068

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Baljinnyam E, Iwatsubo K, Kurotani R, Wang X, Ulucan C, Iwatsubo M, Lagunoff D, Ishikawa Y. Epac increases melanoma cell migration by a heparan sulfate-related mechanism. Am J Physiol Cell Physiol 297: C802-C813, 2009. First published August 5, 2009; doi:10.1152/ajpcell.00129.2009.-Melanoma, the most malignant form of human skin cancer, has a poor prognosis due to its strong metastatic ability. It was recently demonstrated that Epac, an effector molecule of cAMP, is involved in regulating cell migration; however, the role of Epac in melanoma cell migration remains unclear. We thus examined whether Epac regulates cell migration and metastasis of melanoma. Epac activation, by either specific agonist or overexpression of Epac, increased melanoma cell migration. Deletion of endogenous Epac with small interfering RNA decreased basal melanoma cell migration. These data suggested a major role of Epac in melanoma cell migration. Epac-induced cell migration was mediated by translocation of syndecan-2, a cell-surface heparan sulfate proteoglycan, to lipid rafts. This syndecan-2 translocation was regulated by tubulin polymerization via the Epac/phosphoinositol-3 kinase pathway. Epac-induced cell migration was also regulated by the production of heparan sulfate, a major extracellular matrix. Epac-induced heparan sulfate production was attributable to the increased expression of N-deacetylase/N-sulfotransferase-1 (NDST-1) accompanied by an increased NDST-1 translation rate. Finally, Epac overexpression enhanced lung colonization of melanoma cells in mice. Taken together, these data indicate that Epac regulates melanoma cell migration/metastasis mostly via syndecan-2 translocation and heparan sulfate production.

DOI： 10.1152/ajpcell.00129.2009

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

The ductus arteriosus (DA), an essential vascular shunt for fetal circulation, begins to close immediately after birth. Although Ca2+ influx through several membrane Ca2+ channels is known to regulate vasoconstriction of the DA, the role of the T-type voltage-dependent Ca2+ channel (VDCC) in DA closure remains unclear. Here we found that the expression of alpha 1G, a T-type isoform that is known to exhibit a tissue-restricted expression pattern in the rat neonatal DA, was significantly up-regulated in oxygenated rat DA tissues and smooth muscle cells (SMCs). Immunohistological analysis revealed that alpha 1G was localized predominantly in the central core of neonatal DA at birth. DA SMC migration was significantly increased by alpha 1G overexpression. Moreover, it was decreased by adding alpha 1G-specific small interfering RNAs or using R(-)-efonidipine, a highly selective T-type VDCC blocker. Furthermore, an oxygenation-mediated increase in an intracellular Ca2+ concentration of DA SMCs was significantly decreased by adding alpha 1G-specific siRNAs or using R(-)-efonidipine. Although a prostaglandin E receptor EP4 agonist potently promoted intimal thickening of the DA explants, R(-)-efonidipine (10(-6) M) significantly inhibited EP4-promoted intimal thickening by 40% using DA tissues at preterm in organ culture. Moreover, R(-)-efonidipine (10(-6) M) significantly attenuated oxygenation-induced vasoconstriction by similar to 27% using a vascular ring of fetal DA at term. Finally, R(-)-efonidipine significantly delayed the closure of in vivo DA in neonatal rats. These results indicate that T-type VDCC, especially alpha 1G, which is predominantly expressed in neonatal DA, plays a unique role in DA closure, implying that T-type VDCC is an alternative therapeutic target to regulate the patency of DA.

DOI： 10.1074/jbc.M109.017061

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記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Jiao Q, Bai Y, Akaike T, Takeshima H, Ishikawa Y, Minamisawa S. Sarcalumenin is essential for maintaining cardiac function during endurance exercise training. Am J Physiol Heart Circ Physiol 297: H576-H582, 2009. First published June 5, 2009; doi:10.1152/ajpheart.00946.2008.-Sarcalumenin (SAR), a Ca(2+)-binding protein located in the longitudinal sarcoplasmic reticulum (SR), regulates Ca(2+) reuptake into the SR by interacting with cardiac sarco(endo) plasmic reticulum Ca(2+)-ATPase 2a (SERCA2a). We have previously demonstrated that SAR deficiency induced progressive heart failure in response to pressure overload, despite mild cardiac dysfunction in sham-operated SAR knockout (SARKO) mice (26). Since responses to physiological stresses often differ from those to pathological stresses, we examined the effects of endurance exercise on cardiac function in SARKO mice. Wild-type (WT) and SARKO mice were subjected to endurance treadmill exercise training (similar to 65% of maximal exercise ability for 60 min/day) for 12 wk. After exercise training, maximal exercise ability was significantly increased by 5% in WT mice (n = 6), whereas it was significantly decreased by 37% in SARKO mice (n = 5). Cardiac function assessed by echocardiographic examination was significantly decreased in accordance with upregulation of biomarkers of cardiac stress in SARKO mice after training. After training, expression levels of SERCA2a protein were significantly downregulated by 30% in SARKO hearts, whereas they were significantly upregulated by 59% in WT hearts. Consequently, SERCA2 activity was significantly decreased in SARKO hearts after training. Furthermore, the expression levels of other Ca(2+)-handling proteins, including phospholamban, ryanodine receptor 2, calsequestrin 2, and sodium/calcium exchanger 1, were significantly decreased in SARKO hearts after training. These results indicate that SAR plays a critical role in maintaining cardiac function under physiological stresses, such as endurance exercise, by regulating Ca(2+) transport activity into the SR. SAR may be a primary target for exercise-related adaptation of the Ca(2+) storage system in the SR to preserve cardiac function.

DOI： 10.1152/ajpheart.00946.2008

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Vascular remodeling after mechanoinjury largely depends on the migration of smooth muscle cells, an initial key step to wound healing. However, the role of the second messenger system, in particular, the cAMP signal, in regulating such remodeling remains controversial. Exchange protein activated by cAMP ( Epac) has been identified as a new target molecule of the cAMP signal, which is independent from PKA. We thus examined whether Epac plays a distinct role from PKA in vascular remodeling. To examine the role of Epac and PKA in migration, we used primary culture smooth muscle cells from both the fetal and adult rat aorta. A cAMP analog selective to PKA, 8-(4-parachlorophenylthio)-cAMP (pCPT-cAMP), decreased cell migration, whereas an Epac-selective analog, 8-pCPT-2'-O-Me-cAMP, enhanced migration. Adenovirus-mediated gene transfer of PKA decreased cell migration, whereas that of Epac1 significantly enhanced cell migration. Striking morphological differences were observed between pCPT-cAMP- and 8-pCPT-2'-O-Me-cAMP-treated aortic smooth muscle cells. Furthermore, overexpression of Epac1 enhanced the development of neointimal formation in fetal rat aortic tissues in organ culture. When the mouse femoral artery was injured mechanically in vivo, we found that the expression of Epac1 was upregulated in vascular smooth muscle cells, whereas that of PKA was downregulated with the progress of neointimal thickening. Our findings suggest that Epac1, in opposition to PKA, increases vascular smooth muscle cell migration. Epac may thus play an important role in advancing vascular remodeling and restenosis upon vascular injury.

DOI： 10.1152/ajpheart.01317.2007

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

We have demonstrated that chronic stimulation of the prostaglandin E-2-cAMP-dependent protein kinase A (PKA) signal pathway plays a critical role in intimal cushion formation in perinatal ductus arteriosus (DA) through promoting synthesis of hyaluronan. We hypothesized that Epac, a newly identified effector of cAMP, may play a role in intimal cushion formation (ICF) in the DA distinct from that of PKA. In the present study, we found that the levels of Epac1 and Epac2 mRNAs were significantly up-regulated in the rat DA during the perinatal period. A specific EP4 agonist, ONO-AE1 -329, increased Rap1 activity in the presence of a PKA inhibitor, PKI-(14-22)-amide, in DA smooth muscle cells. 8-pCPT-2-O-Me-cAMP (O-Me-cAMP), a cAMP analog selective to Epac activator, promoted migration of DA smooth muscle cells (SMC) in a dose-dependent manner. Adenovirus-mediated Epac1 or Epac2 gene transfer further enhanced O-Me-cAMP-induced cell migration, although the effect of Epac1 overexpression on cell migration was stronger than that of Epac2. In addition, transfection of small interfering RNAs for Epac1, but not Epac2, significantly inhibited serum-mediated migration of DA SMCs. In the presence of O-Me-cAMP, actin stress fibers were well organized with enhanced focal adhesion, and cell shape was widely expanded. Adenovirus-mediated Epac1, but not Epac2 gene transfer, induced prominent ICF in the rat DA explants when compared with those with green fluorescent protein gene transfer. The thickness of intimal cushion became significantly greater (1.98-fold) in Epac1-overexpressed DA. O-Me-cAMP did not change hyaluronan production, although it decreased proliferation of DA SMCs. The present study demonstrated that Epac, especially Epac1, plays an important role in promoting SMC migration and thereby ICF in the rat DA.

DOI： 10.1074/jbc.M804223200

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

It is well known that autonomic nervous activity is altered under microgravity, leading to disturbed regulation of cardiac function, such as heart rate. Autonomic regulation of the heart is mostly determined by beta-adrenergic receptors/cAMP signal, which is produced by adenylyl cyclase, in cardiac myocytes. To examine a hypothesis that a major cardiac isoform, type 5 adenylyl cyclase (AC5), plays an important role in regulating heart rate during parabolic flights, we used transgenic mouse models with either disrupted (AC5KO) or overexpressed AC5 in the heart (AC5TG) and analyzed heart rate variability. Heart rate had a tendency to decrease gradually in later phases within one parabola in each genotype group, but the magnitude of decrease was smaller in AC5KO than that in the other groups. The inverse of heart rate, i.e., the R-R interval, was much more variable in AC5KO and less variable in AC5TG than that in wild-type controls. The standard deviation of normal R-R intervals, a marker of total autonomic variability, was significantly greater in microgravity phase in each genotype group, but the magnitude of increase was much greater in AC5KO than that in the other groups, suggesting that heart rate regulation became unstable in the absence of AC5. In all, AC5 plays a major role in stabilizing heat rate under microgravity.

DOI： 10.1152/japplphysiol.01166.2007

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Aims Sarcalumenin (SAR) is a Ca2+-binding protein expressed in the longitudinal sarcoplasmic reticulum (SR) of striated muscle cells. Although its Ca2+-binding property is similar to that of calsequestrin, its rote in the regulation of Ca2+ cycling remains unclear.
Methods and results To investigate whether SAR plays an important rote in maintaining cardiac function under pressure overload stress, SAR-knockout (SAR-KO) mice were subjected to transverse aortic constriction (TAC). To examine the relation of SAR with cardiac type of SR Ca2+ PUMP, SERCA2a, we designed cDNA expression using cultured cells. We found that SAR expression was significantly downregulated in hypertrophic hearts from three independent animal, models. SAR-KO mice experienced higher mortality than did wild-type (WT) mice after TAC. TAC significantly downregulated SERCA2a protein but not mRNA in the SAR-KO hearts, whereas it minimally did so in hearts from WT mice. Accordingly, SR Ca2+ uptake and cardiac function were significantly reduced in SAR-KO mice after TAC. Then we found that SAR was co-immunoprecipitated with SERCA2a, in cDNA-transfected HEK293T cells and mouse ventricular muscles, and that SERCA2a-mediated Ca2+ uptake was augmented when SAR was co-expressed in HEK293T cells. Furthermore, SAR significantly prolonged the half-life of SERCA2a protein in HEK293T cells.
Conclusion These findings suggest that functional interaction between SAR and SERCA2a enhances protein stability of SERCA2a and facilitates Ca2+ sequestration into the SR. Thus the SAR-SERCA2a interaction plays an essential role in preserving cardiac function under biomechanical stresses such as pressure overload.

DOI： 10.1093/cvr/cvm019

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記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Background - Desensitizat ion of the cyclic adenosine monophosphate signal protects cardiac myocytes against catecholamine stress, thus preventing the development of apoptosis. Molecular mechanisms of desensitization have been well studied at the level of adrenergic receptors but less so at the level of the effector enzyme, adenylyl cyclase (AC).
Methods and Results - When the effects of long-term (I to 2 weeks) isoproterenol infusion were compared between type 5 AC-null mice (AC5KO) and wild-type controls, we found that the subsequent responses of left ventricular ejection fraction to sudden intravenous isoproterenol challenge were reduced in AC5KO compared with wild-type mice (ie, physiological desensitization was more effective in AC5KO), consistent with enhanced downregulation of AC catalytic activity in AC5KO. One mechanism for the less effective desensitization in wild-type mice was paradoxical upregulation of type 5 AC protein expression. The number of apoptotic myocytes was similar at baseline but was significantly less in AC5KO after infusion. This was accompanied by a 4-fold greater increase in Bcl-2 and a 3-fold greater increase in phospho-Akt in AC5KO. The latter is most likely mediated by increased membrane localization of phosphoinositide-dependent protein kinase 1, which is known to be inhibited by the cyclic adenosine monophosphate signal.
Conclusions - The absence of type 5 AC results in more effective desensitization after long-term catecholamine stress and protects against the development of myocyte apoptosis and deterioration of cardiac function, potentially elucidating a novel approach to the therapy of heart failure.

DOI： 10.1161/CIRCULATIONAHA.107.698662

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記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Voltage-dependent Ca2+ channels (VDCCs), which consist of multiple subtypes, regulate vascular tone in developing arterial smooth muscle, including the ductus arteriosus (DA). First, we examined the expression of VDCC subunits in the Wistar rat DA during development. Among alpha(1)-subunits, alpha(1C) and alpha(1G) were the most predominant isoforms. Maternal administration of vitamin A significantly increased alpha(1C)- and alpha(1G) transcripts. Second, we examined the effect of VDCC subunits on proliferation of DA smooth muscle cells. We found that 1 mu M nitrendipine (an L-type Ca2+ channel blocker) and kurtoxin (a T-type Ca2+ channel blocker) significantly decreased [H-3] thymidine incorporation and that 3 mu M efonidipine (an L- and T-type Ca2+ channel blocker) further decreased [H-3] thymidine incorporation, suggesting that L- and T-type Ca2+ channels are involved in smooth muscle cell proliferation in the DA. Third, we found that a novel alternatively spliced variant of the alpha(1C)-isoform was highly expressed in the neointimal cushion of the DA, where proliferating and migrating smooth muscle cells are abundant. The basic channel properties of the spliced variant did not differ from those of the conventional alpha(1C)-subunit. We conclude that multiple VDCC subunits were identified in the DA, and, in particular, alpha(1C)- and alpha(1G)-subunits were predominant in the DA. A novel spliced variant of the alpha(1C)-subunit gene may play a distinct role in neointimal cushion formation in the DA.

DOI： 10.1152/ajpheart.00100.2004

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Adenylyl cyclase, a major target enzyme of beta-adrenergic receptor signals, is potently and directly inhibited by P-site inhibitors, classic inhibitors of this enzyme, when the enzyme catalytic activity is high. Unlike beta-adrenergic receptor antagonists, this is a non- or uncompetitive inhibition with respect to ATP. We have examined whether we can utilize this enzymatic property to regulate the effects of beta-adrenergic receptor stimulation differentially. After screening multiple new and classic compounds, we found that some compounds, including 1R, 4R-3-(6-aminopurin-9-yl)-cyclopentanecarboxylic acid hydroxyamide, potently inhibited type 5 adenylyl cyclase, the major cardiac isoform, but not other isoforms. In normal mouse cardiac myocytes, contraction induced by low beta-adrenergic receptor stimulation was poorly inhibited with this compound, but the induction of cardiac myocyte apoptosis by high beta-adrenergic receptor stimulation was effectively prevented by type 5 adenylyl cyclase inhibitors. In contrast, when cardiac myocytes from type 5 adenylyl cyclase knock-out mice were examined, beta-adrenergic stimulation poorly induced apoptosis. Our data suggest that the inhibition of beta-adrenergic signaling at the level of the type 5 adenylyl cyclase isoform by P-site inhibitors may serve as an effective method to prevent cardiac myocyte apoptosis induced by excessive beta-adrenergic stimulation without deleterious effect on cardiac myocyte contraction.

DOI： 10.1074/jbc.M314238200

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Neuronal nicotinic acetylcholine receptors (nAChRs) are made of multiple subunits with diversified functions. The nAChR alpha(7)-subunit has a property of high Ca2+ permeability and may have specific functions and localization within the plasma membrane as a signal transduction molecule. In PC-12 cells, fractionation by sucrose gradient centrifugation revealed that nAChRalpha(7) existed in low-density, cholesterol-enriched plasma membrane microdomains known as lipid rafts where flotillin also exists. In contrast, nAChR alpha(5)- and beta(2)-subunits were located in high-density fractions, out of the lipid rafts. Type 6 adenylyl cyclase (AC6), a calcium-inhibitable isoform, was also found in lipid rafts and was coimmunoprecipitated with nAChRalpha(7). Cholesterol depletion from plasma membranes with methyl-beta-cyclodextrin redistributed nAChRalpha(7) and AC6 diffusely within plasma membranes. Nicotine stimulation reduced forskolin-stimulated AC activity by 35%, and this inhibition was negated by either treatment with alpha-bungarotoxin, a specific antagonist of nAChRalpha(7), or cholesterol depletion from plasma membranes. The effect of cholesterol depletion was negated by the addition of cholesterol. These data suggest that nAChRalpha(7) has a specific membrane localization relative to other nAChR subunits and that lipid rafts are necessary to localize nAChRalpha(7) with AC within plasma membranes. In addition, nAChRalpha(7) may regulate the AC activity via Ca2+ within lipid rafts.

DOI： 10.1152/ajpcell.00422.2002

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1161/01.RES.0000086986.35568.63

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

In a genetically engineered mouse line with disruption of type 5 adenylyl cyclase (AC5(-/-)), a major cardiac isoform, there was no compensatory increase in other isoforms of AC in the heart. Both basal and isoproterenol (ISO)-stimulated AC activities were decreased by 30% to 40% in cardiac membranes. The reduced AC activity did not affect cardiac function (left ventricular ejection fraction [LVEF]) at baseline. However, increases in LVEF after ISO were significantly attenuated in AC5(-/-) (P<0.05, n=11). Paradoxically, conscious AC5(-/)- mice had a higher heart rate compared with wild-type (WT) mice (613±8 versus 523±11 bpm, P<0.01, n=14 to 15). Muscarinic agonists decreased AC activity, LVEF, and heart rate more in WT than in AC5(-/-). In addition, baroreflex-mediated, ie, neuronally regulated, bradycardia after phenylephrine was also attenuated in AC5(-/-). The carbachol-activated outward potassium current (at -40 mV) normalized to cell capacitance in AC5(-/-) (2.6+/-0.4 pA/pF, n=16) was similar to WT (2.9+/-0.3 pA/pF, n=27), but calcium (Ca2+)-mediated inhibition of AC activity and Ca2+ channel function were diminished in AC5(-/-). Thus, AC5(-/-) attenuates sympathetic responsiveness and also impairs parasympathetic and Ca2+-mediated regulation of the heart, indicating that those actions are not only regulated at the level of the receptor and G-protein but also at the level of type 5 AC.

DOI： 10.1161/01.RES.0000086986.35568.63

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATL ACAD SCIENCES  

The sympathetic nervous system is designed to respond to stress. Adenylyl cyclase (AC) is the keystone of sympathetic transmission, yet its role in response to acute overload in the heart or in the pathogenesis of heart failure is controversial. We examined the effects of pressure overload, induced by thoracic aortic banding, in mice in which type 5 AC, a major cardiac AC isoform, was disrupted (AC5(-/-)). Left ventricular weight/tibial length ratio (LVW/TL) was not different between the WT and AC5(-/-) at baseline and increased progressively and similarly in both groups at 1 and 3 wk after aortic banding. However, LV ejection fraction (LVEF) fell in WT at 3 wk after banding (from 70 +/- 2.8 to 57 +/- 3.9%, P < 0.05), and this decrease was associated with LV dilatation, indicating incipient cardiac failure. In contrast, AC5(-/-) mice did not exhibit a fall in LVEF from 74 +/- 2.2%. The number of apoptotic myocytes was similar at baseline, but it increased roughly 4-fold in WT at both 1 and 3 wk after banding, and significantly less, P < 0.05, in AC5(-/-). importantly, the increase in apoptosis occurred before the decline in LVEF in WT. The protective mechanism seems to involve Bcl-2, which was up-regulated significantly more in AC5(-/-) mice with pressure overload. Our findings suggest that limiting type 5 AC plays a protective role in response to pressure overload and the development of heart failure, potentially through limiting the incidence of myocardial apoptosis.

DOI： 10.1073/pnas.1733772100

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Various neurotransmitters, such as dopamine, stimulate adenylyl cyclase to produce cAMP, which regulates neuronal functions. Genetic disruption of the type 5 adenylyl cyclase isoform led to a major loss of adenylyl cyclase activity in a striatum-specific manner with a small increase in the expression of a few other adenylyl cyclase isoforms. D1 dopaminergic agonist-stimulated adenylyl cyclase activity was attenuated, and this was accompanied by a decrease in the expression of the D1 dopaminergic receptor and G(s)alpha. D2 dopaminergic agonist-mediated inhibition of adenylyl cyclase activity was also blunted. Type 5 adenylyl cyclase-null mice exhibited Parkinsonian-like motor dysfunction, i.e. abnormal coordination and bradykinesia detected by Rotarod and pole test, respectively, and to a lesser extent locomotor impairment was detected by open field tests. Selective D1 or D2 dopaminergic stimulation improved some of these disorders in this mouse model, suggesting the partial compensation of each dopaminergic receptor signal through the stimulation of remnant adenylyl cyclase isoforms. These findings extend our knowledge of the role of an effector enzyme isoform in regulating receptor signaling and neuronal functions and imply that this isoform provides a site of convergence of both D1 and D2 dopaminergic signals and balances various motor functions.

DOI： 10.1074/jbc.C300075200

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Intracellular Ca2+ regulation is critical in the normal cardiac function and development of pathologic hearts. Phospholamban, an endogenous inhibitor of sarcoplasmic reticulum Ca2+ ATPase in the sarcoplasmic reticulum, plays an important role in Ca2+ cycling in heart. Recently, sarcolipin has been identified as having a similar function as phospholamban in skeletal muscle. Because phospholamban is differentially expressed in atrial and ventricular myocardia and its expression is often altered in diseased hearts, we investigated the cardiac chamber specificity of sarcolipin expression and its regulation during development and hypertrophic remodeling. Northern blot analysis revealed that the expression of mouse sarcolipin mRNA was most abundant in the atria and was undetectable in the ventricles, indicating an atrial chamber-specific expression pattern. Atrial chamber-specific expression of sarcolipin mRNA was increased during development. These findings were confirmed by in situ hybridization studies. In addition, sarcolipin expression was down-regulated in the atria of hypertrophic heart when induced by ventricular specific overexpression of the activated H-ras gene. In humans, sarcolipin mRNA was also expressed in the atria but not detected in the ventricles, although sarcolipin expression was most abundant in skeletal muscle. Taken together, sarcolipin is likely to be an atrial chamber-specific regulator of Ca2+ cycling in heart.

DOI： 10.1074/jbc.M213132200

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Crystallographic studies have elucidated the binding mechanism of forskolin and P-site inhibitors to adenylyl cyclase. Accordingly, computer-assisted drug design has enabled us to identify isoform-selective regulators of adenylyl cyclase. After examining more than 200 newly synthesized derivatives of forskolin, we found that the modification at the positions of C6 and C7, in general, enhances isoform selectivity. The 6-(3-dimethylaminopropionyl) modification led to an enhanced selectivity for type V, whereas 6-[N-(2-isothiocyanatoethyl) aminocarbonyl] and 6-(4-acrylbutyryl) modification led to an enhanced selectivity for type II. In contrast, 2'-deoxyadenosine 3'-monophosphate, a classical and 3'-phosphate-substituted P-site inhibitor, demonstrated a 27-fold selectivity for inhibiting type V relative to type II, whereas 9-(tetrahydro-2-furyl) adenine, a ribose-substituted P-site ligand, showed a markedly increased, 130-fold selectivity for inhibiting type V. Consequently, on the basis of the pharmacophore analysis of 9-(tetrahydro-2-furyl) adenine and adenylyl cyclase, a novel nonnucleoside inhibitor, 2-amino-7-(2-furanyl)-7,8-dihydro-5(6H)-quinazolinone (NKY80), was identified after virtual screening of more than 850,000 compounds. NKY80 demonstrated a 210-fold selectivity for inhibiting type V relative to type II. More importantly, the combination of a type III-selective forskolin derivative and 9-(tetrahydro-2-furyl) adenine or NKY80 demonstrated a further enhanced selectivity for type III stimulation over other isoforms. Our data suggest the feasibility of adenylyl cyclase isoform-targeted regulation of cyclic AMP signaling by pharmacological reagents, either alone or in combination.

DOI： 10.1074/jbc.M107233200

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Objective: Caveolin, a major protein component of caveolae, is now considered to be an inhibitor of cellular growth and proliferation. In this study, we examined the localization of the molecules involved in al-adrenergic receptor signal relative to that of caveolin in the heart and the changes in caveolin expression during the development of hypertrophy in SHR. Methods: We purified the caveolar protein fractions from rat cardiac tissues, H9C2 cells, and rat vascular smooth muscle cells. Using radioligand receptor binding assay and immunoblot analysis, we examined the distribution and the amount of alpha1-AR and caveolin. Results: Caveolin-3, the alpha1-adrenergic receptor, Gq and PLC-beta ubtypes (PLC-beta1, -beta3) were found exclusively in the caveolar fraction in the above tissues. Caveolin-3 were co-immunoprecipitated with alpha1-adrenergic receptor and Gq from the cardiac tissues. The amount of caveolin subtypes expression (caveolin-1 and -3) and the amount of the al-adrenergic receptor were examined in the hearts of SHR and age-matched WKY (4- and 24-weeks-old). The amount of caveolin-3 expression was significantly smaller in SHR at 24-weeks-old than that in SHR at 4-weeks-old and that in WKY at 24-weeks-old. Conclusions: The molecules involved in alpha1-adrenergic signaling are confined to the same microdomain as caveolin. A decrease in caveolin-3 expression may play a role in the development of cardiac hypertrophy in SHR, presumably through de-regulating the inhibition of growth signal in the hearts of SHR in the hypertrophic stage. (C) 2001 Elsevier Science B.V. All rights reserved.

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Ovid Technologies (Wolters Kluwer Health)  

DOI： 10.1161/01.res.86.7.802

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC CLINICAL INVESTIGATION INC  

Transgenic (TG) mice with cardiac G(s alpha) overexpression exhibit enhanced inotropic and chronotropic responses to sympathetic stimulation, but develop cardiomyopathy with age. We tested the hypothesis that cardiomyopathy in TG mice with Gs alpha overexpression could be averted with chronic beta-adrenergic receptor (beta-AR) blockade. TG mice and age-matched wild-type littermates were treated with the beta-AR blocker propranolol for 6-7 months, starting at a time when the cardiomyopathy was developing but was not yet severe enough to induce significant cardiac depression (9.5 months of age), and ending at a time when cardiac depression and cardiomyopathy would have been clearly manifest (16 months of age). Propranolol treatment, which can induce cardiac depression in the normal heart, actually prevented cardiac dilation and the depressed left ventricular function characteristic of older TG mice, and abolished premature mortality. Propranolol also prevented the increase in myocyte cross-sectional area and myocardial fibrosis. Myocyte apoptosis, already apparent in 3-month-old TG mice, was actually eliminated by chronic propranolol. This study indicates that chronic sympathetic stimulation over an extended period is deleterious and results in cardiomyopathy. Conversely, PAR blockade is salutary in this situation and can prevent the development of cardiomyopathy.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ENDOCRINE SOC  

The cAMP-signaling pathway is composed of multiple components ranging from receptors, G proteins, and adenylyl cyclase to protein kinase A. A common view of the molecular interaction between them is that these molecules are disseminated on the plasma lipid membrane and random collide with each other to transmit signals. A limitation to this idea, however, is that a signaling cascade involving multiple components may not occur rapidly. Caveolae and their principal component, caveolin, have been implicated in transmembrane signaling, particularly in G protein-coupled signaling. We examined whether caveolin interacts with adenylyl cyclase, the membrane-bound enzyme that catalyzes the conversion of ATP to cAMP. When overexpressed in insect cells, types ill, IV, and V adenylyl cyclase were localized in caveolin-enriched membrane fractions. Caveolin was coimmunoprecipitated with adenylyl cyclase in tissue homogenates and copurified with a polyhistidine-tagged form of adenylyl cyclase by Ni-nitrilotriacetic acid resin chromatography in insect cells, suggesting the colocalization of adenylyl cyclase and caveolin in the same microdomain. Further, the regulatory subunit of protein kinase A (RII alpha, but not RI alpha) was also enriched in the same fraction as caveolin. Gs alpha was found in both caveolin-enriched and non-caveolin-enriched membrane fractions. Our data suggest that the cAMP-signaling cascade occurs within a restricted microdomain of the plasma membrane in a highly organized manner.

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/s0002-9149(99)00266-0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

The goal of this study was to determine the extent to which the effects of milrinone were desensitized in heart failure (HF) and to determine the mechanisms, i.e., whether these effects could be ascribed to changes in cAMP or phosphodiesterase (PDE) activity in HF. Accordingly, we examined the effects of milrinone in seven conscious dogs before and after HF was induced by rapid ventricular pacing at 240 beats/min. The dogs were chronically instrumented for measurements of left ventricular (LV) pressure and first derivative of LV pressure (dP/dt), arterial pressure, LV internal diameter, and wall thickness. Milrinone (10 mu g . kg(-1) . min(-1) iv) increased LV dP/dt by 1,854 +/- 157 from 2,701 +/- 105 mmHg/s (P < 0.05) before HF. After HF the increase in LV dP/dt in response to milrinone was attenuated significantly (P < 0.05); it increased by 615 +/- 67 from 1,550 +/- 107 mmHg/s, indicating marked desensitization. In the presence of ganglionic blockade the increases in LV dP/dt (+445 +/- 65 mmHg/s) in response to milrinone were markedly less (P < 0.01), and milrinone increased LV dP/dt even less in HF (+240 +/- 65 mmHg/s). cAMP and PDE activity were measured in endocardial and epicardial layers in normal and failing myocardium. cAMP was decreased significantly (P < 0.05) in LV endocardium (-26%) but not significantly in LV epicardium (-14%). PDE activity was also decreased significantly (P < 0.05) in LV endocardium (-18%) but not in LV epicardium (-4%). Thus significant desensitization to milrinone was observed in conscious dogs with HF. The major effect was autonomically mediated. The biochemical mechanism appears to be due in part to the modest reductions in PDE activity in failing myocardium, which, in turn, may be a compensatory mechanism to maintain cAMP levels in HF. Reductions in cAMP and PDE levels were restricted to the subendocardium, suggesting that the increased wall stress and reduced coronary reserve play a role in mediating these changes.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1152/ajpheart.1999.276.5.H1699

PubMed

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Society for Clinical Investigation  

DOI： 10.1172/jci4848

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1172/jci1530

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ENDOCRINE SOC  

Caveolae and their principal component caveolin have been implicated in playing a major role in G protein-mediated transmembrane signaling. We examined whether caveolin interacts with adenylyl cyclase, an effector of G protein signaling, using a 20-mer peptide derived from the N-terminus scaffolding domain of caveolin-1. When tissue adenylyl cyclases were examined, cardiac adenylyl cyclase was inhibited more potently than other tissue adenylyl cyclases. The caveolin-1 peptide inhibited type V, as well as type III adenylyl cyclase, overexpressed in insect cells, whereas the same peptide had no effect on type II. The caveolin-3 scaffolding domain peptide similarly inhibited type V adenylyl cyclase. In contrast, peptides derived from the caveolin-2 scaffolding domain and a caveolin-1 nonscaffolding domain had no effect. Kinetic studies showed that the caveolin-1 peptide decreased the maximal rate (V-max) value of type V without changing the Michaelis constant (Km) value for the substrate ATP. Studies with various truncations and point mutations of this peptide revealed that a minimum of 16 amino acid residues and intact aromatic residues are important for the inhibitory effect. The potency of inhibition was greater when adenylyl cyclase was in stimulated condition vs. basal condition. Thus, caveolin may be another cellular component that regulates adenylyl cyclase catalytic activity. Our results also suggest that the caveolin peptide may be used as an isoform-selective inhibitor of adenylyl cyclase.

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Ovid Technologies (Wolters Kluwer Health)  

DOI： 10.1161/01.res.82.4.416

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Caveolar localization of protein kinase C and the regulation of caveolar function by protein kinase C are well known, This study was undertaken to examine whether caveolin subtypes interact with various protein kinase C isoenzymes using the caveolin scaffolding domain peptide. When protein kinase C-alpha, -epsilon, and -zeta were overexpressed in COS cells followed by subcellular fractionation using the sucrose gradient method, all the isoenzymes (alpha, epsilon, and zeta) were detected in the same fraction as caveolin. The scaffolding domain peptide of caveolin-1 and -3, but not -2, inhibited the kinase activity and autophosphorylation of protein kinase C-alpha and -zeta, but not of protein kinase C-epsilon, overexpressed in insect cells. Truncation mutation studies of the caveolin-1 and -3 peptides demonstrated that a minimum of 16 or 14 amino acid residues of the peptide were required for the inhibition or direct binding of protein kinase C, Thus, the caveolin peptide physically interacted with protein kinase C and regulated its function. Further, this regulation occurred in a protein kinase C isoenzyme-dependent manner. Our results may provide a new mechanism regarding the regulation of protein kinase C isoenzyme activity and the molecular interaction of protein kinase C with its putative binding proteins.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Caveolae, flask-shaped invaginations of cell membranes, are believed to play pivotal roles in transmembrane transportation of molecules and cellular signaling. Caveolin, a structural component of caveolae, interacts directly with G proteins and regulates their function. We investigated the effect of chronic beta-adrenergic receptor stimulation on the expression of caveolin subtypes in mouse hearts by immunoblotting and Northern blotting. Caveolin-1 and -3 were abundantly expressed in the heart and skeletal muscles, but not in the brain. Continuous (-)-isoproterenol, but not (+)-isoproterenol, infusion via osmotic minipump (30 mu g.g(-1).day(-1)) for 13 days significantly downregulated both caveolin subtypes in the heart. The expression of caveolin-1 was reduced by 48 +/- 6.1% and that of caveolin-3 by 28 +/- 4.0% (P < 0.01, n = 8 for each). The subcellular distribution of caveolin subtypes in ventricular myocardium was not altered as determined by sucrose gradient fractionation. In contrast, the expression of both caveolin subtypes in skeletal muscles was not significantly changed. Our data suggest that the expression of caveolin subtypes is regulated by beta-adrenergic receptor stimulation in the heart.

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Physiological Society  

The goal of this study was to determine whether chronic endogenous sympathetic stimulation resulting from the overexpression of cardiac stimulatory G protein alpha subunit (Gs alpha) in transgenic mice (15.3 +/- 0.1 mo old) resulted in a clinical picture of cardiomyopathy. The left ventricular ejection fraction, measured by echocardiography, was reduced in older mice with Gs alpha overexpression (50.4 +/- 5.4%) compared with age-matched control mice (70.9 +/- 1.6%; P < 0.05). When ejection fractions were compared at similar heart rates, the Gs alpha mice exhibited a greater left ventricular end-diastolic dimension than control mice (4.3 +/- 0.2 vs. 3.7 +/- 0.1 mm; P < 0.05). Baseline heart rates were elevated in conscious Gs alpha mice (722 +/- 27 beats/min; n = 5) compared with control mice (656 +/- 28 beats/min; n = 5). Moreover, electrocardiographic monitoring demonstrated a high incidence of arrhythmias. Increased mortality compared with control mice (31.6 vs. 3.0%; P< 0.01) was also observed. Thus older mice with Gs alpha overexpression exhibit many of the features of dilated cardiomyopathy. This study supports the concept that chronic sympathetic stimulation over an extended period of time, i.e., over the life of an animal, is deleterious and actually may result in cardiomyopathy.

DOI： 10.1152/ajpheart.1997.272.1.h585

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

An insect ovarian cell, Spodoptera frugiperda (Sf9), has been widely used to express recombinant proteins, including adenylyl cyclase, as a host cell in the baculovirus expression system. We report the presence and characterization of a soluble adenylyl cyclase (sAC) distinct from a membrane-bound form of adenylyl cyclase (mAC) that is also present in Sf9 cells. sAC was purified 3,500-fold to near homogeneity; a single band at 25 kDa on SDS-polyacrylamide gel electrophoresis correlated well with adenylyl cyclase catalytic activity. The purified enzyme had a catalytic activity of 0.1 mu mol/min . mg and the K-m of 0.55 mM for the substrate ATP. In contrast to mAC, sAC was heat-stable. Enzymatic activity of sAC was not stimulated by forskolin and was inhibited by salts at high concentrations. sAC utilized both manganese- and magnesium-ATP as substrate. Di- or triphosphate-containing nucleotides, such as GTP and GDP, as well as pyrophosphate, noncompetitively inhibited sAC. Our data suggest that the physical and biochemical characteristics of sAC are different from those of mAC in Sf9 cells as well as from those of other known forms of adenylyl cyclase in animal cells; sAC in Sf9 cells may constitute a new member of adenylyl cyclase found in animals.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

The changing relationship between stimuli and responses after prolonged receptor stimulation is a general feature of hormonal signaling systems, termed desensitization. This phenomenon has been best exemplified in the covalent modification of the G protein-linked catecholamine receptors. However, other components within this signaling pathway can be involved in desensitization. Here we present evidence that desensitization occurs at the level of the effector enzyme itself through phosphorylation. Type V adenylyl cyclase (AC) is the major isoform expressed in the heart. Using purified enzymes, we demonstrate that protein kinase A (PKA) directly phosphorylates and thereby inhibits type V AC catalytic activity, This inhibition was negated in the presence of PKA inhibitor. Analysis of enzyme kinetics revealed that this inhibition was due to a decrease in the catalytic rate, not to a decrease in the affinity for the substrate ATP. Our results indicate that AC catalytic activity can be regulated through PKA-mediated phosphorylation, suggesting another mechanism of desensitization for receptor pathways which signal via increases in intracellular cAMP.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Cyclic AMP production within cells is altered upon protein kinase C (PKC) activation; however, whether PKC directly modulates adenylyl cyclase (AC) catalytic activity has been controversial. Molecular studies have elucidated the existence of multiple PKC isoenzymes although the functional role of this diversity is not clear. Using purified PKC and AC isoenzymes, we demonstrate that PKC zeta directly phosphorylates type VAC, leading to an approximate 20-fold increase in its catalytic activity, a significantly larger enhancement than that achieved with forskolin (similar to 5-fold), the most potent activator of AC. When forskolin and PKC phosphorylation are combined, type V AC catalytic activity is increased 100-fold over basal levels. The two PKC isoenzymes (alpha and zeta) are additive in their capacity to activate AC, although PKC alpha is less potent than PKC zeta. Our data indicate that PKC can directly and potently regulate AC activity in an isoenzyme-specific manner, suggesting that direct cross-talk plays a major role in coordinating the activity of these two principal signal transduction pathways.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROCKEFELLER UNIV PRESS  

We have shown that the heart expresses two distinct forms of adenylylcyclase mRNA, types V and VI. In this study we have characterized the expression of these two mRNA species in heart failure generated by overdrive pacing at a rate of 240 beats/min. After 4 wk, left ventricular end-diastolic pressure and heart rate increased significantly with the appearance of signs of heart failure, i.e., edema, ascites, and exercise intolerance. Basal as well as forskolin-stimulated adenylylcyclase activities decreased significantly, which was accompanied by a reduction in the steady state mRNA levels of adenylylcyclase types V and VI. These data suggest that in this model of cardiomyopathy, the downregulation of adenylylcyclase catalytic activity results, at least in part, from a reduction in the steady state levels of types V and VI adenylylcyclase mRNA levels.

DOI： 10.1172/JCI117219

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATL ACAD PRESS  

A sixth member of the mammalian adenylyl cyclase family has been isolated from a canine cardiac cDNA library. This isoform is more highly homologous to type V than to the other adenylyl cyclase types; sequence similarity is apparent even in the transmembrane regions where the greatest divergence among the types exists. Type VI mRNA expression is most abundant in heart and brain; however, unlike type V, a low level of expression is also observed in a variety of other tissues examined. Type VI adenylyl cyclase can be stimulated by NaF, guanosine 5'-[gamma-thio]triphosphate, and forskolin but not by Ca2+/calmodulin, whereas it is inhibited by adenosine and its analogues. Comparison of both their structural and biochemical properties suggests that types V and VI constitute a distinct subgroup of the mammalian adenylyl cyclase family.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

A novel adenylylcyclase cDNA (type V) was isolated from a canine heart cDNA library. Northern blotting indicates that the expression of this message is most abundant in heart with a lesser amount in brain but is absent in a variety of other tissues including lung, kidney, skeletal muscle, lymphocyte, and testis. The putative protein product predicted from the cDNA sequence has the motif of tandem six-transmembrane spans separated by a large hydrophilic cytoplasmic loop as seen in other members of the adenylylcyclase family. When this protein is expressed using a CMT cell transient expression system, the adenylylcyclase activity was stimulated by NaF, GTP-gamma-S, and forskolin, but not by calmodulin. The activity was inhibited in a concentration-dependent manner with either P-site active agents such as adenosine or in the presence of calcium. These data indicate that the protein encoded by this cDNA is adenylylcyclase with the biochemical features characteristic of the cardiac isoform.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: The increasing prevalence of heated tobacco products (HTPs) has heightened concerns regarding their potential health risks. Previous studies have demonstrated the toxicity of cigarette smoke extract (CSE) from traditional tobacco's mainstream smoke, even after the removal of nicotine and tar. Our study aimed to investigate the cytotoxicity of CSE derived from HTPs and traditional tobacco, with a particular focus on the role of reactive oxygen species (ROS) and intracellular Ca2+. METHODS: A human oral squamous cell carcinoma (OSCC) cell line, HSC-3 was utilized. To prepare CSE, aerosols from HTPs (IQOS) and traditional tobacco products (1R6F reference cigarette) were collected into cell culture media. A cell viability assay, apoptosis assay, western blotting, and Fluo-4 assay were conducted. Changes in ROS levels were measured using electron spin resonance spectroscopy and the high-sensitivity 2',7'-dichlorofluorescein diacetate assay. We performed a knockdown of calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) by shRNA lentivirus in OSCC cells. RESULTS: CSE from both HTPs and traditional tobacco exhibited cytotoxic effects in OSCC cells. Exposure to CSE from both sources led to an increase in intracellular Ca2+ concentration and induced p38 phosphorylation. Additionally, these extracts prompted cell apoptosis and heightened ROS levels. N-acetylcysteine (NAC) mitigated the cytotoxic effects and p38 phosphorylation. Furthermore, the knockdown of CaMKK2 in HSC-3 cells reduced cytotoxicity, ROS production, and p38 phosphorylation in response to CSE. CONCLUSION: Our findings suggest that the CSE from both HTPs and traditional tobacco induce cytotoxicity. This toxicity is mediated by ROS, which are regulated through Ca2+ signaling and CaMKK2 pathways.

DOI： 10.1186/s12576-024-00928-1

PubMed

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

Abstract

Application of physical forces, ranging from ultrasound to electric fields, is recommended in various clinical practice guidelines, including those for treating cancers and bone fractures. However, the mechanistic details of such treatments are often inadequately understood, primarily due to the absence of comprehensive study models. In this study, we demonstrate that an alternating magnetic field (AMF) inherently possesses a direct anti‐cancer effect by enhancing oxidative phosphorylation (OXPHOS) and thereby inducing metabolic reprogramming. We observed that the proliferation of human glioblastoma multiforme (GBM) cells (U87 and LN229) was inhibited upon exposure to AMF within a specific narrow frequency range, including around 227 kHz. In contrast, this exposure did not affect normal human astrocytes (NHA). Additionally, in mouse models implanted with human GBM cells in the brain, daily exposure to AMF for 30 min over 21 days significantly suppressed tumor growth and prolonged overall survival. This effect was associated with heightened reactive oxygen species (ROS) production and increased manganese superoxide dismutase (MnSOD) expression. The anti‐cancer efficacy of AMF was diminished by either a mitochondrial complex IV inhibitor or a ROS scavenger. Along with these observations, there was a decrease in the extracellular acidification rate (ECAR) and an increase in the oxygen consumption rate (OCR). This suggests that AMF‐induced metabolic reprogramming occurs in GBM cells but not in normal cells. Our results suggest that AMF exposure may offer a straightforward strategy to inhibit cancer cell growth by leveraging oxidative stress through metabolic reprogramming.

DOI： 10.1111/cas.16243

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

Abstract

Lymph node metastasis, primarily caused by the migration of oral squamous cell carcinoma (OSCC) cells, stands as a crucial prognostic marker. We have previously demonstrated that EP4, a subtype of the prostaglandin E2 (PGE2) receptor, orchestrates OSCC cell migration via Ca²⁺ signaling. The exact mechanisms by which EP4 influences cell migration through Ca²⁺ signaling, however, is unclear. Our study aims to clarify how EP4 controls OSCC cell migration through this pathway. We find that activating EP4 with an agonist (ONO-AE1-473) increased intracellular Ca²⁺ levels and the migration of human oral cancer cells (HSC-3), but not human gingival fibroblasts (HGnF). Further RNA sequencing linked EP4 to calmodulin-like protein 6 (CALML6), whose role remains undefined in OSCC. Through protein-protein interaction network analysis, a strong connection is identified between CALML6 and calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), with EP4 activation also boosting mitochondrial function. Overexpressing EP4 in HSC-3 cells increases experimental lung metastasis in mice, whereas inhibiting CaMKK2 with STO-609 markedly lowers these metastases. This positions CaMKK2 as a potential new target for treating OSCC metastasis. Our findings highlight CALML6 as a pivotal regulator in EP4-driven mitochondrial respiration, affecting cell migration and metastasis via the CaMKK2 pathway.

DOI： 10.1038/s42003-024-06231-4

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その他リンク： https://www.nature.com/articles/s42003-024-06231-4

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Biologically compatible vascular grafts are urgently required. The scaffoldless multi-layered vascular wall is considered to offer theoretical advantages, such as facilitating cells to form cell-cell and cell-matrix junctions and natural extracellular matrix networks. Simple methods are desired for fabricating physiological scaffoldless tissue-engineered vascular grafts. Here, we showed that periodic hydrostatic pressurization under hypoxia (HP/HYP) facilitated the fabrication of multi-layered tunica media entirely from human vascular smooth muscle cells. Compared with normoxic atmospheric pressure, HP/HYP increased expression of N-myc downstream-regulated 1 (NDRG1) and the collagen-cross-linking enzyme lysyl oxidase in human umbilical artery smooth muscle cells. HP/HYP increased N-cadherin-mediated cell-cell adhesion via NDRG1, cell-matrix interaction (i.e., clustering of integrin α5β1 and fibronectin), and collagen fibrils. We then fabricated vascular grafts using HP/HYP during repeated cell seeding and obtained 10-layered smooth muscle grafts with tensile rupture strength of 0.218-0.396 MPa within 5 weeks. Implanted grafts into the rat aorta were endothelialized after 1 week and patent after 5 months, at which time most implanted cells had been replaced by recipient-derived cells. These results suggest that HP/HYP enables fabrication of scaffoldless human vascular mimetics that have a spatial arrangement of cells and matrices, providing potential clinical applications for cardiovascular diseases. STATEMENT OF SIGNIFICANCE: Tissue-engineered vascular grafts (TEVGs) are theoretically more biocompatible than prosthetic materials in terms of mechanical properties and recipient cell-mediated tissue reconstruction. Although some promising results have been shown, TEVG fabrication processes are complex, and the ideal method is still desired. We focused on the environment in which the vessels develop in utero and found that mechanical loading combined with hypoxia facilitated formation of cell-cell and cell-matrix junctions and natural extracellular matrix networks in vitro, which resulted in the fabrication of multi-layered tunica media entirely from human umbilical artery smooth muscle cells. These scaffoldless TEVGs, produced using a simple process, were implantable and have potential clinical applications for cardiovascular diseases.

DOI： 10.1016/j.actbio.2023.09.041

PubMed

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1186/s12576-023-00878-0

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記述言語：日本語   出版者・発行元：日本病態生理学会  

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記述言語：日本語   出版者・発行元：日本病態生理学会  

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記述言語：日本語   出版者・発行元：(NPO)日本小児循環器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/jcs6050136

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Despite exhibiting cardiotoxicity, doxorubicin (DOX) is widely used for cancer treatments. Cardiac fibroblasts (CFs) are important in the pathogenesis of heart failure. This necessitates the study of the effect of DOX on CFs. The impairment of calcium (Ca2+) homeostasis is a common mechanism of heart failure. Store-operated Ca2+ entry (SOCE) is a receptor-regulated Ca2⁺ entry pathway that maintains calcium balance by sensing reduced calcium stores in the endoplasmic reticulum. ORAI1, a calcium channel protein and the most important component of SOCE, is highly expressed in human cardiac fibroblasts (HCFs). It is upregulated in CFs from failing ventricles. However, whether ORAI1 in HCFs is increased and/or plays a role in DOX-induced cardiotoxicity remains unknown. In this study, we aimed to elucidate the relationship between ORAI1/SOCE and DOX-induced heart failure. Induction of apoptosis by DOX was characterized in HCFs. Apoptosis and cell cycle analyses were performed by fluorescence-activated cell sorting (FACS). Reactive oxygen species (ROS) production was measured using fluorescence. YM-58483 was used as an ORAI1/SOCE inhibitor. ORAI1-knockdown cells were established by RNA interference. In vivo experiments were performed by intraperitoneally injecting YM-58483 and DOX into mice. We first demonstrated that DOX significantly increased the protein expression level of p53 in HCFs by western blotting. FACS analysis revealed that DOX increased early apoptosis and induced cell cycle arrest in the G2 phase in fibroblasts. DOX also increased ROS production. DOX significantly increased the expression level of ORAI1 in CFs. Both YM-58483 and ORAI1 gene knockdown attenuated DOX-induced apoptosis. Similarly, YM-58483 attenuated cell cycle arrest in the G2 phase, and ORAI1 knockdown attenuated DOX-induced ROS production in HCFs. In the animal experiment, YM-58483 attenuated DOX-induced apoptosis. In HCFs, ORAI1/SOCE regulates p53 expression and plays an important role in DOX-induced cardiotoxicity. ORAI1 may serve as a new target for preventing DOX-induced heart failure.

DOI： 10.1371/journal.pone.0278613

PubMed

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記述言語：日本語   出版者・発行元：日本病態生理学会  

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記述言語：日本語   出版者・発行元：日本病態生理学会  

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記述言語：日本語   出版者・発行元：横浜市立大学医学会  

我々は鉄錯体の一種であるμ-oxo N,N-bis(salicylidene)ethylenediamine iron[以後,Fe(Salen)と呼ぶ]が有機化合物でありながら,抗腫瘍効果を持ち,さらに磁性を持つ(磁石に付き,強磁性の挙動を示す)ことを発見した.無機化合物が磁性を持つことはよく知られるが,有機化合物が常温で磁性を示すという報告は世界で初めてである.また,Fe(Salen)の磁場発生メカニズムの解析のため,結晶構造解析を行ったことで「磁場発生の原因となる化学構造」を同定し,その磁場発生メカニズムを突き止めた.Fe(Salen)は磁性を持つため,主に3つのユニークな特徴を持つ.1)磁力により体外から任意の場所にFe(Salen)を集積させること(ドラッグデリバリー)ができる.2)磁性を持つことでMRIのT2強調画像で低信号を示し,局在や濃度の推定が期待できる.3)磁性体は交流磁場で発熱するという特徴(IHクッキングヒーターと同じ原理)も持つため,温熱療法への応用が期待できる.我々は長年,Fe(Salen)のユニークな特徴を生かすべく,治療法を検討してきた.その後,Fe(Salen)をパクリタキセルと共有結合させ,パクリタキセルの薬効成分の磁性化に成功した.動物実験において磁力で磁性パクリタキセルを局所に集積させ,薬剤濃度を高めることで,治療効果が増強することを確認した.この磁性化技術が確立すれば,様々な市販医薬品を磁性化することが期待でき,薬剤単剤で複数の付加価値を得ることができる.本総説では,我々が10年以上取り組んで来た磁性抗がん剤についての研究内容についてまとめ,今後の展望を試みる.(著者抄録)

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記述言語：日本語   出版者・発行元：横浜市立大学医学会  

我々は鉄錯体の一種であるμ-oxo N,N-bis(salicylidene)ethylenediamine iron[以後,Fe(Salen)と呼ぶ]が有機化合物でありながら,抗腫瘍効果を持ち,さらに磁性を持つ(磁石に付き,強磁性の挙動を示す)ことを発見した.無機化合物が磁性を持つことはよく知られるが,有機化合物が常温で磁性を示すという報告は世界で初めてである.また,Fe(Salen)の磁場発生メカニズムの解析のため,結晶構造解析を行ったことで「磁場発生の原因となる化学構造」を同定し,その磁場発生メカニズムを突き止めた.Fe(Salen)は磁性を持つため,主に3つのユニークな特徴を持つ.1)磁力により体外から任意の場所にFe(Salen)を集積させること(ドラッグデリバリー)ができる.2)磁性を持つことでMRIのT2強調画像で低信号を示し,局在や濃度の推定が期待できる.3)磁性体は交流磁場で発熱するという特徴(IHクッキングヒーターと同じ原理)も持つため,温熱療法への応用が期待できる.我々は長年,Fe(Salen)のユニークな特徴を生かすべく,治療法を検討してきた.その後,Fe(Salen)をパクリタキセルと共有結合させ,パクリタキセルの薬効成分の磁性化に成功した.動物実験において磁力で磁性パクリタキセルを局所に集積させ,薬剤濃度を高めることで,治療効果が増強することを確認した.この磁性化技術が確立すれば,様々な市販医薬品を磁性化することが期待でき,薬剤単剤で複数の付加価値を得ることができる.本総説では,我々が10年以上取り組んで来た磁性抗がん剤についての研究内容についてまとめ,今後の展望を試みる.(著者抄録)

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Many studies have revealed numerous potential biomarkers for atherosclerosis, but tissue-specific biomarkers are still needed. Recent lineage-tracing studies revealed that smooth muscle cells (SMCs) contribute substantially to plaque formation, and the loss of SMCs causes plaque vulnerability. We investigated the association of SMC-specific myosin heavy chain 11 (myosin-11) with atherosclerosis. Forty-five patients with atherosclerosis and 34 control subjects were recruited into our study. In the atherosclerosis patients, 35 patients had either coronary artery disease (CAD) or peripheral artery disease (PAD), and 10 had both CAD and PAD. Coronary arteries isolated from five patients were subjected to histological study. Circulating myosin-11 levels were higher in the CAD or PAD group than in controls. The area under the receiver operating characteristic curve of myosin-11 was 0.954. Circulating myosin-11 levels in the CAD and PAD group were higher than in the CAD or PAD group, while high-sensitivity C-reactive protein concentrations did not differ between these groups. Multinomial logistic regression analyses showed a significant association of myosin-11 levels with the presence of multiple atherosclerotic regions. Myosin-11 was expressed in the medial layer of human atherosclerotic lesions where apoptosis elevated. Circulating myosin-11 levels may be useful for detecting spatial expansion of atherosclerotic regions.

DOI： 10.3390/jcm10143155

PubMed

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Association for the Advancement of Science (AAAS)  

There is urgent demand for biologically compatible vascular grafts for both adult and pediatric patients. The utility of conventional nonbiodegradable materials is limited because of their thrombogenicity and inability to grow, while autologous vascular grafts involve considerable disadvantages, including the invasive procedures required to obtain these healthy vessels from patients and insufficient availability in patients with systemic atherosclerosis. All of these issues could be overcome by tissue-engineered vascular grafts (TEVGs). A large body of evidence has recently emerged in support of TEVG technologies, introducing diverse cell sources (e.g., somatic cells and stem cells) and novel fabrication methods (e.g., scaffold-guided and self-assembled approaches). Before TEVG can be applied in a clinical setting, however, several aspects of the technology must be improved, such as the feasibility of obtaining cells, their biocompatibility and mechanical properties, and the time needed for fabrication, while the safety of supplemented materials, the patency and nonthrombogenicity of TEVGs, their growth potential, and the long-term influence of implanted TEVGs in the body must be assessed. Although recent advances in TEVG fabrication have yielded promising results, more research is needed to achieve the most feasible methods for generating optimal TEVGs. This article reviews multiple aspects of TEVG fabrication, including mechanical requirements, extracellular matrix components, cell sources, and tissue engineering approaches. The potential of periodic hydrostatic pressurization in the production of scaffold-free TEVGs with optimal elasticity and stiffness is also discussed. In the future, the integration of multiple technologies is expected to enable improved TEVG performance.

DOI： 10.34133/2021/1532103

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その他リンク： http://downloads.spj.sciencemag.org/cbsystems/2021/1532103.xml

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Tissue-engineered vascular grafts (TEVGs) are in urgent demand for both adult and pediatric patients. Although several approaches have utilized vascular smooth muscle cells (SMCs) and endothelial cells as cell sources for TEVGs, these cell sources have a limited proliferative capacity that results in an inability to reconstitute neotissues. Skeletal myoblasts are attractive cell sources as they possess high proliferative capacity, and they are already being tested in clinical trials for patients with ischemic cardiomyopathy. Our previous study demonstrated that periodic hydrostatic pressurization (PHP) promoted fibronectin fibrillogenesis in vascular SMCs, and that PHP-induced extracellular matrix (ECM) arrangements enabled the fabrication of implantable arterial grafts derived from SMCs without using a scaffold material. We assessed the molecular response of human skeletal myoblasts to PHP exposure, and aimed to fabricate arterial grafts from the myoblasts by exposure to PHP. To examine the PHP-response genes, human skeletal myoblasts were subjected to bulk RNA-sequencing after PHP exposure. Gene-set enrichment analysis revealed significant positive correlations between PHP exposure and vascular development-related genes. Real-time polymerase chain reaction (RT-PCR) demonstrated that PHP significantly upregulated collagen and elastic fiber formation-related gene expression, such as fibronectin, lysyl oxidase, collagen type I α1, collagen type IV α1, and tropoelastin. Based on these findings showing the potential role of PHP in vessel formation, we fabricated arterial grafts by repeated cell seeding and exposure to PHP every 24 hours. The resultant 15-layered myoblast grafts had high collagen content, which provided a tensile rupture strength of 899 ± 104 mm Hg. Human skeletal myoblast grafts were implanted as patch grafts in the aorta of immunosuppressed rats and found to be endothelialized and completely patent until the endpoint of 60 postoperative days. Implanted human myoblasts were gradually replaced by host-derived cells, which successfully formed vascular neotissues with layered elastic fibers. These findings suggest that human skeletal myoblasts have the potential to be a feasible cell source for scaffold-free implantable arterial grafts under PHP culture conditions.

DOI： 10.1111/aor.13930

PubMed

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掲載種別：研究論文（学術雑誌）   出版者・発行元：SAGE Publications  

Colorectal anastomotic leakage is one of the most feared and fatal complications of colorectal surgery. To date, no external coating material that can prevent anastomotic leakage has been developed. As myoblasts possess anti-inflammatory capacity and improve wound healing, we developed a multilayered human skeletal muscle myoblast (HSMM) sheet by periodic exposure to supraphysiological hydrostatic pressure during repeated cell seeding. We assessed whether the application of an HSMM sheet can promote the healing process after colonic anastomosis. Partial colectomy and insufficient suturing were employed to create a high-risk colo-colonic anastomosis model in 60 nude rats. Rats were divided into a control group ( n = 30) and an HSMM sheet group ( n = 30). Macroscopic findings, anastomotic bursting pressure, and histology at the colonic anastomotic site were evaluated on postoperative day (POD) 3, 5, 7, 14, and 28. The application of an HSMM sheet significantly suppressed abscess formation at the anastomotic site compared to the control group on POD3 and 5. The anastomotic bursting pressure in the HSMM sheet group was higher than that in the control group on POD3 and 5. Inflammatory cell infiltration in the HSMM sheet group was significantly suppressed compared to that in the control group throughout the time course. Collagen deposition in the HSMM sheet group on POD3 was significantly abundant compared to that in the control group. Regeneration of the mucosa at the colonic anastomotic site was promoted in the HSMM sheet group compared to that in the control group on POD14 and 28. Immunohistochemical analysis demonstrated that surviving cells in the HSMM sheet gradually decreased with postoperative time and none were detected on POD14. These results suggest that the application of a multilayered HSMM sheet may prevent postoperative colonic anastomotic leakage.

DOI： 10.1177/09636897211009559

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その他リンク： http://journals.sagepub.com/doi/full-xml/10.1177/09636897211009559

記述言語：英語   出版者・発行元：東京医科大学医学会  

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その他リンク： https://search.jamas.or.jp/default/link?pub_year=2021&ichushi_jid=J00877&link_issn=&doc_id=20210924430042&doc_link_id=%2Fcr4tokyo%2F2021%2Fs07901%2F033%2F0104-0104%26dl%3D0&url=https%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Fcr4tokyo%2F2021%2Fs07901%2F033%2F0104-0104%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

記述言語：英語   出版者・発行元：東京医科大学医学会  

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記述言語：日本語   出版者・発行元：東京医科大学医学会  

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その他リンク： https://search-tp.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2021&ichushi_jid=J00877&link_issn=&doc_id=20210924430058&doc_link_id=%2Fcr4tokyo%2F2021%2Fs07901%2F049%2F0112-0112%26dl%3D0&url=https%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Fcr4tokyo%2F2021%2Fs07901%2F049%2F0112-0112%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

掲載種別：研究論文（学術雑誌）   出版者・発行元：Japanese Pharmacological Society  

DOI： 10.1254/fpj.20101

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記述言語：日本語   出版者・発行元：東京医科大学医学会  

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その他リンク： https://search-tp.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2020&ichushi_jid=J00877&link_issn=&doc_id=20201113360054&doc_link_id=%2Fcr4tokyo%2F2020%2Fs07803%2F046%2F0301-0301%26dl%3D0&url=https%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Fcr4tokyo%2F2020%2Fs07803%2F046%2F0301-0301%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circrep.CR-20-0015

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記述言語：英語   掲載種別：論文集(書籍)内論文  

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Springer Singapore  

Antenatal betamethasone (BTM) is a standard therapy to reduce respiratory distress syndrome [1], and some reports indicate that BTM decreases prevalence of patent ductus arteriosus in preterm infants [2]. Closure of the ductus arteriosus (DA) requires morphological remodeling, i.e., intimal thickening (IT) formation [3]. However, the role of BTM in IT formation of the preterm DA has not been reported.

DOI： 10.1007/978-981-15-1185-1_38

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Springer Singapore  

The normal closure of the ductus arteriosus (DA) consists of two steps: vasoconstriction and intimal thickening (IT). We have revealed that prostaglandin E2 (PGE2)-EP4 signaling plays a critical role in IT formation via smooth muscle cell (SMC) migration through hyaluronic acid [1]. In this study, we found that fibulin-1 was the most significantly up-regulated gene by EP4 stimulation in DA smooth muscle cells (SMCs).

DOI： 10.1007/978-981-15-1185-1_39

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記述言語：日本語   出版者・発行元：(一社)日本脳循環代謝学会  

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記述言語：日本語   出版者・発行元：(一社)日本救急医学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41419-019-1787-7

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DOI： 10.1177/0218492319865446

PubMed

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記述言語：日本語   出版者・発行元：(公財)臨床薬理研究振興財団  

本研究では、著者等が合成に成功した市販抗がん剤の薬効成分を磁性化した市販医薬品である磁性メトトレキサート(Magnetized-MTX)を用いて関節リウマチに対する新規治療法を開拓することを目指した。まず、磁性メトトレキサートが、磁性を化学合成により付与された後、実際に磁性を持つかおよび薬効が保たれているかを確認した。その結果、磁性メトトレキサートは磁石により集積し、電子スピン共鳴(ESR)測定と超伝導量子干渉計(SQUID)測定で共に磁性があることが分かった。細胞株を用いた磁性メトトレキサートの抗腫瘍効果の評価試験では、磁性メトトレキサートはヒト滑膜肉腫細胞(SW982)やラット骨肉腫細胞(POS-1)に対して濃度依存的に増殖抑制効果を、SW982細胞に対して濃度依存的にアポトーシス誘導効果を、ヒト子宮頸部癌細胞(Hela細胞)においては濃度依存的にERKリン酸化抑制効果を示した。また、磁性メトトレキサートでHela細胞を6時間刺激後、磁性メトトレキサートによる濃度依存的な活性酸素の産生が認めた。次にマウスを用いて、磁性メトトレキサートが磁石により集積するかどうかの実験を行った。その結果、磁石によって磁性メトトレキサートが局所に集積したことが分かった。今後は、磁性メトトレキサートについても関節リウマチ疾患モデルマウスを使用して、実際に磁気サポーターで磁性メトトレキサートの挙動をコントロールし、関節リウマチに薬剤血中濃度を高めることで、より高い治療効果が得られることについて検討中である。

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記述言語：英語  

DOI： 10.1007/s12576-019-00661-0

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Vascular smooth muscle cell (VSMC) migration and the subsequent intimal thickening play roles in vascular restenosis. We previously reported that an exchange protein activated by cAMP 1 (Epac1) promotes platelet-derived growth factor (PDGF)-induced VSMC migration and intimal thickening. Because basic fibroblast growth factor (bFGF) also plays a pivotal role in restenosis, we examined whether Epac1 was involved in bFGF-mediated VSMC migration. bFGF-induced lamellipodia formation and migration were significantly decreased in VSMCs obtained from Epac1-/- mice compared to those in Epac1+/+-VSMCs. The bFGF-induced phosphorylation of Akt and glycogen synthase kinase 3β (GSK3β), which play a role in bFGF-induced cell migration, was attenuated in Epac1-/--VSMCs. Intimal thickening induced by the insertion of a large wire was attenuated in Epac1-/- mice, and was accompanied by the decreased phosphorylation of GSK3β. These data suggest that Epac1 deficiency attenuates bFGF-induced VSMC migration, possibly via Akt/GSK3β pathways.

DOI： 10.1007/s12576-018-0631-7

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Antenatal betamethasone (BMZ) is a standard therapy for reducing respiratory distress syndrome in preterm infants. Recently, some reports have indicated that BMZ promotes ductus arteriosus (DA) closure. DA closure requires morphological remodeling; that is, intimal thickening (IT) formation; however, the role of BMZ in IT formation has not yet been reported. Methods and Results: First, DNA microarray analysis using smooth muscle cells (SMCs) of rat preterm DA on gestational day 20 (pDASMCs) stimulated with BMZ was performed. Among 58,717 probe sets, ADP-ribosyltransferase 3 (Art3) was markedly increased by BMZ stimulation. Quantitative reverse transcription polymerase chain reaction (RT-PCR) confirmed the BMZ-induced increase of Art3 in pDASMCs, but not in aortic SMCs. Immunocytochemistry showed that BMZ stimulation increased lamellipodia formation. BMZ significantly increased total paxillin protein expression and the ratio of phosphorylated to total paxillin. A scratch assay demonstrated that BMZ stimulation promoted pDASMC migration, which was attenuated byArt3-targeted siRNAs transfection. pDASMC proliferation was not promoted by BMZ, which was analyzed by a 5'-bromo-2'-deoxyuridine (BrdU) assay. Whether BMZ increased IT formation in vivo was examined. BMZ or saline was administered intravenously to maternal rats on gestational days 18 and 19, and DA tissues were obtained on gestational day 20. The ratio of IT to tunica media was significantly higher in the BMZ-treated group. CONCLUSIONS: These data suggest that antenatal BMZ administration promotes DA IT through Art3-mediated DASMC migration.

DOI： 10.1253/circj.CJ-18-1033

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Elsevier  

There is great interest in metal nanoparticle (MNP)-based local drug-delivery systems (DDSs), but most methods employ drug agents with additional MNPs, and it is challenging to design composite nanosystems involving dissimilar molecular building blocks. In this chapter, we have reviewed the advance of anticancer organometallic agents on the basis of iron complexes. In particular, we have highlighted chemotherapeutically active inorganic iron-complex-based advanced local magneto-DDS composites via self-assembly of iron complexes, without the use of common magnetites and anticancer prodrugs. Distinguishing features of the molecular nanocomposites will be discussed on simultaneous performance of multiple tasks in guided DDS, MRI, and magneto-hyperthermal effect, which will be suitable for a wide variety of “minimally invasive” theranostic clinics, including targeted DDS.

DOI： 10.1016/B978-0-08-102814-8.00015-9

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-18-0743

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1371/journal.pone.0221940

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掲載種別：研究論文（学術雑誌）  

DOI： 10.14814/phy2.13878

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/cas.13781

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Physiological Society  

Mechanical stresses play important roles in the process of constructing and modifying heart structure. It has been well established that stretch force acting on cardiac fibroblasts induces fibrosis. However, the effects of compressive force, that is, hydrostatic pressure (HP), have not been well elucidated. We thus evaluated the effects of HP using a pressure-loading apparatus in human cardiac fibroblasts (HCFs) in vitro. In this study, high HP (200 mmHg) resulted in significant phosphorylation of Akt in HCFs. HP then greatly inhibited glycogen synthase kinase 3 (GSK-3)α, which acts downstream of the PI3K/Akt pathway. Similarly, HP suppressed mRNA transcription of inflammatory cytokine-6, collagen I and III, and matrix metalloproteinase 1, compared with an atmospheric pressure condition. Furthermore, HP inhibited collagen matrix production in a three-dimensional HCF culture. Taken together, high HP suppressed the differentiation of fibroblasts into the myofibroblast phenotype. HP under certain conditions suppressed cardiac fibrosis via Akt/GSK-3 signaling in HCFs. These results might help to elucidate the pathology of some types of heart disease.

DOI： 10.14814/phy2.13687

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Public Library of Science  

Aims The ductus arteriosus (DA) closes after birth to adapt to the robust changes in hemodynam-ics, which require intimal thickening (IT) to occur. The smooth muscle cells of the DA have been reported to play important roles in IT formation. However, the roles of the endothelial cells (ECs) have not been fully investigated. We herein focused on tissue-type plasminogen activator (t-PA), which is a DA EC dominant gene, and investigated its contribution to IT formation in the DA. Methods and results ECs from the DA and aorta were isolated from fetal rats using fluorescence-activated cell sorting. RT-PCR showed that the t-PA mRNA expression level was 2.7-fold higher in DA ECs than in aortic ECs from full-term rat fetuses (gestational day 21). A strong immunoreaction for t-PA was detected in pre-term and full-term rat DA ECs. t-PA-mediated plasminogen-plasmin conversion activates gelatinase matrix metalloproteinases (MMPs). Gelatin zymography revealed that plasminogen supplementation significantly promoted activation of the elastolytic enzyme MMP-2 in rat DA ECs. In situ zymography demonstrated that marked gelatinase activity was observed at the site of disruption in the internal elastic laminae (IEL) in full-term rat DA. In a three-dimensional vascular model, EC-mediated plasminogen-plasmin conversion augmented the IEL disruption. In vivo administration of plasminogen to pre-term rat fetuses (gestational day 19), in which IT is poorly formed, promoted IEL disruption accompanied by gelatinase activation and enhanced IT formation in the DA. Additionally, experiments using five human DA tissues demonstrated that the t-PA expression level was 3.7-fold higher in the IT area than in the tunica media. t-PA protein expression and gelatinase activity were also detected in the IT area of the human DAs. Conclusion t-PA expressed in ECs may help to form IT of the DA via activation of MMP-2 and disruption of IEL.

DOI： 10.1371/journal.pone.0190871

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Tokyo  

Pro-inflammatory cytokines are released in septic shock and impair cardiac function via the Jak-STAT pathway. It is well known that sympathetic and thus catecholamine signaling is activated thereafter to compensate for cardiac dysfunction. The mechanism of such compensation by catecholamine signaling has been traditionally understood to be cyclic AMP-dependent protein kinase (PKA)-mediated enforcement of cardiac contractility. We hypothesized that the exchange protein activated by cAMP (Epac), a newly identified target of cAMP signaling that functions independently of PKA, also plays a key role in this mechanism. In cultured cardiac myocytes, activation of Epac attenuated the inhibitory effect of interleukin-6 on the increase of intracellular Ca2+ concentration and contractility in response to isoproterenol, most likely through inhibition of the Jak-STAT pathway via SOCS3, with subsequent changes in inducible nitric oxide synthase expression. These findings suggest a new role of catecholamine signaling in compensating for cardiac dysfunction in heart failure. Epac and its downstream pathway may be a novel target for treating cardiac dysfunction in endotoxemia.

DOI： 10.1007/s12576-016-0509-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Preterm twins have a higher morbidity rate of patent ductus arteriosus (PDA) than do singletons. However, the effect of multiple births on maturation of the ductus arteriosus (DA) has not been reported. Because intimal thickening (IT) is required for DA anatomical closure, we examined IT development in the DA of preterm twins and singletons. Sheep DA tissues obtained from preterm fetuses were subjected to elastica van Gieson staining to evaluate IT. The total IT score in each DA was the sum of the IT scores obtained from six evenly divided parts of the DA, which was positively correlated with gestational ages in singletons. Total IT scores were smaller in preterm twins than in singletons, although no difference in gestational age, birth weight, or gender ratio was observed. These data suggest that IT development of the DA is attenuated in sheep preterm twins, which may affect the higher morbidity of PDA.

DOI： 10.1007/s12576-017-0565-5

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記述言語：英語   出版者・発行元：(一社)日本癌学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE PHARMACOLOGICAL SOC  

Iron-salen, i.e., mu-oxo-N,N'-bis(salicylidene) ethylenediamine iron (Fe(Salen)) was a recently identified as a new anti-cancer compound with intrinsic magnetic properties. Chelation therapy has been widely used in management of metallic poisoning, because an administration of agents that bind metals can prevent potential lethal effects of particular metal. In this study, we confirmed the therapeutic effect of deferoxamine mesylate (DFO) chelation against Fe(Salen) as part of the chelator antidote efficacy. DFO administration resulted in reduced cytotoxicity and ROS generation by Fe(Salen) in cancer cells. DFO (25 mg/kg) reduced the onset of Fe(Salen) (25 mg/kg)-induced acute liver and renal dysfunction. DFO (300 mg/kg) improves survival rate after systematic injection of a fatal dose of Fe(Salen) (200 mg/kg) in mice. DFO enables the use of higher Fe(Salen) doses to treat progressive states of cancer, and it also appears to decrease the acute side effects of Fe(Salen). This makes DFO a potential antidote candidate for Fe(Salen)-based cancer treatments, and this novel strategy could be widely used in minimally-invasive clinical settings. (C) 2017 The Authors. Production and hosting by Elsevier B.V. on behalf of Japanese Pharmacological Society.

DOI： 10.1016/j.jphs.2017.07.002

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER JAPAN KK  

Melanoma has an extremely poor prognosis due to its rapidly progressive and highly metastatic nature. Several therapeutic drugs have recently become available, but are effective only against melanoma with specific BRAF gene mutation. Thus, there is a need to identify other target molecules. We show here that Transient receptor potential, canonical 3 (TRPC3) is widely expressed in human melanoma. We found that pharmacological inhibition of TRPC3 with a pyrazole compound, Pyr3, decreased melanoma cell proliferation and migration. Similar inhibition was observed when the TRPC3 gene was silenced with short-hairpin RNA (shRNA). Pyr3 induced dephosphorylation of signal transducer and activator of transcription (STAT) 5 and Akt. Administration of Pyr3 (0.05 mg/kg) to mice implanted with human melanoma cells (C8161) significantly inhibited tumor growth. Our findings indicate that TRPC3 plays an important role in melanoma growth, and may be a novel target for treating melanoma in patients.

DOI： 10.1007/s12576-016-0480-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Ultrafine Au quantum clusters (QCs) were synthesized by etching host Au nanoparticles in the presence of ethylenediamine (en) and exhibited both strong photoluminescence (PL) and specific anticancer activity. The cutting-edge feature of this QC compound comprises subnanometer-size rhombohedral Au-8, which consists of 8 units of the anticancer motif, namely, an Au+(en) complex (Au(en) QCs), which contributes to photo-and physicochemical stability as well as subcellular theranostic activity in intracellular PL imaging and in situ targeting. Moreover, the Au(en) QCs can be surface-encapsulated by transferrins (Tf) to create TfAu(en) QCs as a multipurpose drug carrier owing to numerous merits, which include cancer-selective biolabeling, high loading/release efficiency, high activity against drug-resistant tumor cells, low toxicity to normal cells, and physiological stability against biothiols, e.g., glutathiones. These versatile features, which are due to intrinsic optical and anticancer properties, provide potential as a single-drug delivery PL probe for preclinical applications, which has yet to be achieved using conventional nanoclusters.

DOI： 10.1039/c7nr02229h

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Pro-inflammatory cytokines are released in septic shock and impair cardiac function via the Jak-STAT pathway. It is well known that sympathetic stimulation leads to coupling of the beta-adrenergic receptor/Gs/adenylyl cyclase, a membrane-bound enzyme that catalyzes the conversion of ATP to CAMP, thereby stimulating protein kinase A (PICA) and ultimately compensating for cardiac dysfunction. The mechanism of such compensation by catecholamine has been traditionally understood as PKA-mediated enforcement of cardiac contractility. We hypothesized that exchange protein activated by cyclic AMP (Epac), a new target of cAMP signaling that functions independently of protein kinase A, also plays a key role in protection against acute stresses or changes in hemodynamic overload.
Lipopolysaccharide injection induced cytokine release and severe cardiac dysfunction in mouse. In mouse overexpressing Epacl in the heart, however, the magnitude of such dysfunction was significantly smaller. Epacl overexpression inhibited the Jak-STAT pathway, as indicated by decreased phosphorylation of STAT3 and increased SOCS3 expression, with subsequent inhibition of iNOS expression. In cultured cardiomyocytes treated with isoproterenol or forskolin, the increase of SOCS3 expression was blunted when Epacl or PKC alpha was silenced with siRNA. Activation of the cAMP/Epac/PKC alpha pathway protected the heart against cytokine-induced cardiac dysfunction, suggesting a new role of catecholamine signaling in compensating for cardiac dysfunction in heart failure. Epacl and its downstream pathways may be novel targets for treating cardiac dysfunction in endotoxemia. (C) 2017 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.yjmcc.2017.05.014

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CSIRO  

INTRODUCTION: Japan is a developed country with high use of Internet and online platforms for health information. ‘Yahoo! Answer Japan’ is the most commonly used question-and-answer service in Japan. AIM: To explore the information users seek regarding breast cancer from the ‘Yahoo! Answer Japan’ web portal. METHODS: The ‘Yahoo! Answer Japan’ portal was searched for the key word ‘breast cancer’ and all questions searched for the period of 1 January to 31 December 2014 were obtained. The selected questions related to human breast cancer and were not advertisements or promotional material. The questions were categorized using a coding schema. High and low access of the questions were defined by the number of view-counts. RESULTS: Among the 2392 selected questions, six major categories were identified
(1) suspected breast cancer, (2) breast cancer screening, (3) treatment of breast cancer, (4) life with breast cancer, (5) prevention of breast cancer and (6) others. The highest number of questions were treatment related (28.8%) followed by suspected breast cancer-related questions (23.4%) and screening-related questions (20%). Statistical analysis revealed that the treatment- related questions were more likely to be highly accessed. CONCLUSION: Content analysis of Internet question-answer communities is important, as questions posted on these sites would serve as a rich source of direct reflection regarding the health-related information needs of the general population.

DOI： 10.1071/HC16048

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記述言語：英語   出版者・発行元：SPRINGER JAPAN KK  

Coarctation of the aorta (CoA) is defined as a congenital stenosis of the thoracic aorta and is one of the most common congenital cardiovascular diseases. Despite successful surgical treatment for CoA, arterial abnormalities, including refractory hypertension, aortic aneurysm, and proatherogenic phenotypic changes, frequently affect patients' quality of life. Emerging evidence from morphological and molecular biological investigations suggest that the area of CoA is characterized by phenotypic modulation of smooth muscle cells, intimal thickening, and impaired elastic fiber formation. These changes extend to the pre-and post-stenotic aorta and impair arterial elasticity. The aim of this review is to present current findings on the pathology and molecular mechanisms of vascular remodeling due to CoA. In particular, we will discuss the association between CoA and the ductus arteriosus since the most common site for the stenosis is in the proximity of the ductus arteriosus.

DOI： 10.1007/s12576-016-0512-x

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記述言語：英語   出版者・発行元：SPRINGER BASEL AG  

As one of the most important second messengers, 3',5'-cyclic adenosine monophosphate (cAMP) mediates various extracellular signals including hormones and neurotransmitters, and induces appropriate responses in diverse types of cells. Since cAMP was formerly believed to transmit signals through only two direct target molecules, protein kinase A and the cyclic nucleotide-gated channel, the sensational discovery in 1998 of another novel direct effecter of cAMP [exchange proteins directly activated by cAMP (Epac)] attracted a great deal of scientific interest in cAMP signaling. Numerous studies on Epac have since disclosed its important functions in various tissues in the body. Recently, observations of genetically manipulated mice in various pathogenic models have begun to reveal the in vivo significance of previous in vitro or cellular-level findings. Here, we focused on the function of Epac in the heart. Accumulating evidence has revealed that both Epac1 and Epac2 play important roles in the structure and function of the heart under physiological and pathological conditions. Accordingly, developing the ability to regulate cAMP-mediated signaling through Epac may lead to remarkable new therapies for the treatment of cardiac diseases.

DOI： 10.1007/s00018-016-2336-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

Background: In heart failure patients, chronic hyperactivation of sympathetic signaling is known to exacerbate cardiac dysfunction. In this study, the cardioprotective effect of vidarabine, an anti-herpes virus agent, which we identified as a cardiac adenylyl cyclase inhibitor, in dogs with pacing-induced dilated cardiomyopathy (DCM) was evaluated. In addition, the adverse effects of vidarabine on basal cardiac function was compared to those of the beta-blocker, carvedilol.
Methods and Results: Vidarabine and carvedilol attenuated the development of pacing-induced systolic dysfunction significantly and with equal effectiveness. Both agents also inhibited the development of cardiac apoptosis and fibrosis and reduced the Na+-Ca2+ exchanger-1 protein level in the heart. Importantly, carvedilol significantly enlarged the left ventricle and atrium; vidarabine, in contrast, did not. Vidarabine-treated dogs maintained cardiac response to beta-AR stimulation better than carvedilol-treated dogs did.
Conclusions: Vidarabine may protect against pacing-induced DCM with less suppression of basal cardiac function than carvedilol in a dog model.

DOI： 10.1253/circj.CJ-16-0736

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

Background: Extremely preterm infants frequently have patent ductus arteriosus (PDA). Recent recommendations include immediately beginning amino acid supplementation in extremely preterm infants. However, the effect of amino acids on closure of the ductus arteriosus (DA) remains unknown.
Methods and Results: Aminogram results in human neonates at day 2 revealed that the plasma glutamate concentration was significantly lower in extremely preterm infants (<28 weeks' gestation) with PDA than in those without PDA and relatively mature preterm infants (28-29 weeks gestation). To investigate the effect of glutamate on DA closure, glutamate receptor expression in fetal rats was examined and it was found that the glutamate inotropic receptor, a-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) type subunit 1 (GluR1), mRNA was highly expressed in the DA compared to the aorta on gestational day 19 (preterm) and gestational day 21 (term). GluR1 proteins were co-localized with tyrosine hydroxylase-positive autonomic nerve terminals in the rat and human DA. Intraperitoneal administration of glutamate increased noradrenaline production in the rat DA. A whole-body freezing method demonstrated that glutamate administration induced DA contraction in both preterm (gestational day 20) and term rat fetuses. Glutamate-induced DA contraction was attenuated by the calcium-sensitive GluR receptor antagonist, NASPM, or the adrenergic receptor a1 blocker, prazosin.
Conclusions: These data suggest that glutamate induces DA contraction through GluR-mediated noradrenaline production. Supplementation of glutamate might help to prevent PDA in extremely preterm infants.

DOI： 10.1253/circj.CJ-16-0649

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記述言語：英語   出版者・発行元：(一社)日本癌学会  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Type 5 adenylyl cyclase (AC5) plays an important role in the development of chronic catecholamine stress-induced heart failure and arrhythmia in mice. Epac (exchange protein activated by cAMP), which is directly activated by cAMP independent of protein kinase A, has been recently identified as a novel mediator of CAMP signaling in the heart. However, the role of Epac in AC5-mediated cardiac dysfunction and arrhythmias remains poorly understood. We therefore generated AC5 transgenic mice (AC5TG) with selective disruption of the Epac1 gene (AC5TG-Epac1KO), and compared their phenotypes with those of AC5TG after chronic isoproterenol (ISO) infusion. Decreased cardiac function as well as increased susceptibility to pacing-induced atrial fibrillation (AF) in response to ISO were significantly attenuated in AC5TG-Epac1KO mice, compared to AC5TG mice. Increased cardiac apoptosis and cardiac fibrosis were also concomitantly attenuated in AC5TG-Epac1KO mice compared to AC5TG mice. These findings indicate that Epacl plays an important role in AC5-mediated cardiac dysfunction and AF susceptibility. (C) 2016 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2016.04.123

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley-Blackwell Publishing Ltd  

Clenbuterol (CB), a selective β2-adrenergic receptor (AR) agonist, induces muscle hypertrophy and counteracts muscle atrophy. However, it is paradoxically less effective in slow-twitch muscle than in fast-twitch muscle, though slow-twitch muscle has a greater density of β-AR. We recently demonstrated that Epac1 (exchange protein activated by cyclic AMP [cAMP]1) plays a pivotal role in β2-AR-mediated masseter muscle hypertrophy through activation of the Akt and calmodulin kinase II (CaMKII)/histone deacetylase 4 (HDAC4) signaling pathways. Here, we investigated the role of Epac1 in the differential hypertrophic effect of CB using tibialis anterior muscle (TA
typical fast-twitch muscle) and soleus muscle (SOL
typical slow-twitch muscle) of wild-type (WT) and Epac1-null mice (Epac1KO). The TA mass to tibial length (TL) ratio was similar in WT and Epac1KO at baseline and was significantly increased after CB infusion in WT, but not in Epac1KO. The SOL mass to TL ratio was also similar in WT and Epac1KO at baseline, but CB-induced hypertrophy was suppressed in both mice. In order to understand the mechanism involved, we measured the protein expression levels of β-AR signaling-related molecules, and found that phosphodiesterase 4 (PDE4) expression was 12-fold greater in SOL than in TA. These results are consistent with the idea that increased PDE4-mediated cAMP hydrolysis occurs in SOL compared to TA, resulting in a reduced cAMP concentration that is insufficient to activate Epac1 and its downstream Akt and CaMKII/HDAC4 hypertrophic signaling pathways in SOL of WT. This scenario can account for the differential effects of CB on fast- and slow-twitch muscles.

DOI： 10.14814/phy2.12791

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Springer Japan  

The ductus arteriosus (DA) is a shunt vessel between the aorta and the pulmonary artery during the fetal period. It is well recognized that prostaglandin E2 (PGE2) dilates the DA through activation of its receptor EP4 and subsequent cyclic AMP (cAMP) production during the fetal period and that oxygen constricts the DA by inhibiting potassium channels immediately after birth. In addition to the regulation of vascular tone, morphological remodeling of the DA throughout the perinatal period, such as prominent intimal thickening and poor elastogenesis, has been demonstrated. We recently identified the molecular mechanisms of the acquisition of unique morphological remodeling in the DA during development. During the fetal period, PGE2-EP4 signaling decreases elastic fiber formation through degradation of the cross-linking enzyme lysyl oxidase (LOX) and increases hyaluronanmediated intimal thickening in the DA. This remodeling is mediated by activation of the EP4 receptor via diverse downstream intracellular signaling pathways. Hyaluronan-mediated intimal thickening was induced by the EP4-Gs protein-cyclic AMP-protein kinase A pathway. The attenuation of elastogenesis is mediated through a non-cyclic AMP signaling pathway, such as c-src-phospholipase C (PLC). These data suggest that placental PGE2- mediated vascular remodeling via different signaling pathways orchestrates the subsequent luminal DA reorganization, leading to complete obliteration of the DA.

DOI： 10.1007/978-4-431-54628-3_35

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1371/journal.pone.0133664

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER JAPAN KK  

Morphological detection of cancer cells in the rabbit VX2 allograft transplantation model is often difficult in a certain region such as serosal cavity where reactive mesothelial cells mimic cancer cells and both cells share common markers such as cytokeratins. Therefore, tagging VX2 cells with a specific and sensitive marker that easily distinguishes them from other cells would be advantageous. Thus, we tried to establish a successively transplantable, enhanced green fluorescent protein (EGFP)-expressing VX2 model. Cancer cells obtained from a conventional VX2-bearing rabbit were cultured in vitro and transfected with an EGFP-encoding vector, and then successively transplanted in Healthy Japanese White rabbits (HJWRs) (n = 8). Besides, conventional VX2 cells were transplanted in other HJWRs (n = 8). Clinicopathological comparison analyses were performed between the two groups. The success rate of transplantation was 100 % for both groups. The sensitivity and specificity of EGFP for immunohistochemical detection of VX2 cells were 84.3 and 100 %, respectively. No significant differences in cancer cell morphology, tumor size (P = 0.742), Ki-67 labeling index (P = 0.878), or survival rate (P = 0.592) were observed between the two. VX2 cells can be genetically altered, visualized by EGFP, and successively transplanted without significant alteration of morphological and biological properties compared to those of the conventional model.

DOI： 10.1007/s00795-014-0071-2

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Springer Japan  

Some of the derivatives of arachidonic acid, namely, the 5-lipoxygenase (5-LO) metabolites leukotriene B 4 (LTB 4) and cysteinyl-leukotrienes (CysLTs) as well as the microsomal prostaglandin E 2 synthase-1 (mPGES-1) product prostaglandin E 2 (PGE 2), can act as potent pro-inflammatory mediators in vascular diseases. Abdominal aortic aneurysm (AAA) is a vascular pathology characterized by the infiltration of the media and adventitia by immune cells and the subsequent degradation of the medial elastic lamina layer. In human AAA, cyclooxygenase-2 (COX-2) and 5-LO are abundantly expressed, and the roles of PGE 2 and LTs in AAA have recently been a subject of intense investigation. In particular, the PGE 2 receptor EP4 has been suggested to promote cytokine production and proteolytic activation, and the inhibition of EP4 signaling attenuates the progression of murine models of AAA. The LTs LTB 4 and LTD 4 have been shown to stimulate the release of a variety of cytokines and other mediators that can enhance degradation of the extracellular matrix, such as macrophage inflammatory protein-1á and monocyte chemoattractant protein-1. Pharmacological inhibition of these eicosanoids attenuate murine models of AAA. Because no pharmacological therapies are currently available for inhibiting the progression of AAA, regulation of the PGE 2 and 5-LO pathways may serve as a new therapeutic strategy for AAA.

DOI： 10.1007/978-4-431-55669-5_19

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BioMed Central Ltd.  

Background: Exendin-4, an exogenous glucagon-like peptide-1 receptor (GLP-1R) agonist, protects the heart from ischemia/reperfusion injury. However, the mechanisms for this protection are poorly understood. Caveolae, sarcolemmal invaginations, and caveolins, scaffolding proteins in caveolae, localize molecules involved in cardiac protection. We tested the hypothesis that caveolae and caveolins are essential for exendin-4 induced cardiac protection using in vitro and in vivo studies in control and caveolin-3 (Cav-3) knockout mice (Cav-3 KO). Methods: Myocytes were treated with exendin-4 and then incubated with methyl-β-cyclodextrin (MβCD) to disrupt caveolae formation. This was then followed by simulated ischemia/reperfusion (SI/R). In addition, cardiac protection in vivo was assessed by measuring infarct size and cardiac troponin levels. Results: Exendin-4 protected cardiac myocytes (CM) from SI/R [35.6 ± 12.6% vs. 64.4 ± 18.0% cell death, P = 0.034] and apoptosis but this protection was abolished by MβCD (71.8 ± 10.8% cell death, P = 0.004). Furthermore, Cav-3/ GLP-1R co-localization was observed and membrane fractionation by sucrose density gradient centrifugation of CM treated with MβCD + exendin-4 revealed that buoyant (caveolae enriched) fractions decreased Cav-3 compared to CM treated with exendin-4 exclusively. Furthermore, exendin-4 induced a reduction in infarct size and cardiac troponin relative to control (infarct size: 25.1 ± 8.2% vs. 41.4 ± 4.1%, P &lt
0.001
troponin: 36.9 ± 14.2 vs. 101.1 ± 22.3 ng/ml, P &lt
0.001). However, exendin-4 induced cardiac protection was abolished in Cav-3 KO mice (infarct size: 43.0 ± 6.4%, P &lt
0.001
troponin: 96.8 ± 26.6 ng/ml, P = 0.001). Conclusions: We conclude that caveolae and caveolin-3 are critical for exendin-4 induced protection of the heart from ischemia/reperfusion injury.

DOI： 10.1186/s12933-014-0132-9

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記述言語：英語   出版者・発行元：OXFORD UNIV PRESS  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Background: In the `Millennium Genome Project', we identified ATP2B1 as a gene responsible for hypertension through single-nucleotide polymorphism analysis. The ATP2B1 gene encodes the plasma membrane calcium ATPase isoform 1, which contributes to the maintenance of intracellular calcium homeostasis by removing calcium ions.
Method: Since ATP2B1 knockout mice are reported to be embryo-lethal, we generated systemic heterozygous ATP2B1 null (ATP2B1(+/-)) mice, and evaluated the implication of ATP2B1 in blood pressure.
Results: ATP2B1(+/-) mice revealed significantly higher SBP as measured by a radiotelemetric method. Phenylephrine-induced vasoconstriction was significantly increased in vascular rings from ATP2B1(+/-) mice, and the difference in this contraction disappeared in the presence of a nitric oxide synthase (NOS) inhibitor. Vasorelaxation to acetylcholine was significantly attenuated in vascular rings from ATP2B1(+/-) mice. In addition, cultured endothelial cells of ATP2B1(+/-) mice showed that the phosphorylation (Ser-1177) level of endothelial NOS protein was significantly lower, and nitric oxide production in endothelial cells and aorta was lower compared with those in control mice. In contrast, neural NOS expression in vascular smooth muscle cells from ATP2B1(+/-) mice and control mice were not significantly different.
Conclusion: These results suggest that decreased ATP2B1 gene expression is associated with impaired endothelial NOS activity and nitric oxide production, and the ATP2B1 gene plays a crucial role in the regulation of blood pressure.

DOI： 10.1097/HJH.0000000000000206

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記述言語：日本語   出版者・発行元：(一社)日本頭頸部癌学会  

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記述言語：英語   出版者・発行元：SPRINGER JAPAN KK  

DOI： 10.1007/s12576-014-0308-9

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：3  

DOI： 10.1007/s12576-014-0309-8

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER IRELAND LTD  

Objective: Elastic fiber formation is disrupted with age and by health conditions including aneurysms and atherosclerosis. Despite considerable progress in the understanding of elastogenesis using the planar culture system and genetically modified animals, it remains difficult to restore elastic fibers in diseased vessels. To further study the molecular mechanisms, in vitro three-dimensional vascular constructs need to be established. We previously fabricated vascular smooth muscle cells (SMCs) into three-dimensional cellular multilayers (3DCMs) using a hierarchical cell manipulation technique, in which cells were coated with fibronectin-gelatin nanofilms to provide adhesive nano-scaffolds. Since fibronectin is known to assemble and activate elastic fiber-related molecules, we further optimized culture conditions.
Methods and results: Elastica stain, immunofluorescence, and electron microscopic analysis demonstrated that 3DCMs, which consisted of seven layers of neonatal rat aortic SMCs cultured in 1% fetal bovine serum (FBS) in Dulbecco's modified Eagle's medium, exhibited layered elastic fibers within seven days of being in a static culture condition. In contrast, the application of adult SMCs, 10% FBS, e-poly(lysine) as an alternative adhesive for fibronectin, or four-layered SMCs, failed to generate layered elastic fiber formation. Radioimmunoassay using [H-3] valine further confirmed the greater amount of crosslinked elastic fibers in 3DCMs than in monolayered SMCs. Layered elastic fiber formation in 3DCMs was inhibited by the lysyl oxidase inhibitor beta-aminopropionitrile, or prostaglandin E-2. Furthermore, infiltration of THP-1-derived macrophages decreased the surrounding elastic fiber formation in 3DCMs.
Conclusion: 3DCMs may offer a new experimental vascular model to explore pharmacological therapeutic strategies for disordered elastic fiber homeostasis. (C) 2014 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.atherosclerosis.2014.01.045

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

Aims: Geranylgeranylacetone (GGA) is commonly utilized to protect the gastric mucosa in peptic ulcer disease. Recently GGA has been shown to protect the myocardium from ischemia/reperfusion by activating heat shock proteins. However, the exact mechanism as to how GGA activates these protective proteins is unknown. Caveolae and caveolin-3 (Cav-3) have been implicated in ischemia, anesthetic, and opioid induced cardiac protection. Given the lipophilic nature of GGA it is our hypothesis that GGA induced cardiac protection requires caveolae and Cav-3.
Main methods: We used an in vivo mouse model of ischemia-reperfusion injury and performed biochemical assays in excised hearts.
Key findings: GGA treated control mice revealed increased caveolae formation and caveolin-3 in buoyant fractions, mediating heat shock protein 70 activation. Furthermore, control mice treated with GGA were protected against ischemia/reperfusion injury whereas Cav-3 knockout (Cav-3 MO) mice were not. Troponin levels confirmed myocardial damage. Finally, Cav-3 KO mice treated with GGA were not protected against mitochondrial swelling whereas control mice had significant protection.
Significance: This study showed that caveolae and caveolin-3 are essential in facilitating GGA induced cardiac protection by optimizing spatial and temporal signaling to the mitochondria. (C) 2014 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.lfs.2014.02.019

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PUBLIC LIBRARY SCIENCE  

Signaling via heterotrimeric G-protein is involved in the development of human diseases including ischemia-reperfusion injury of the heart. We previously identified an ischemia-inducible G-protein activator, activator of G-protein signaling 8 (AGS8), which regulates G beta gamma signaling and plays a key role in the hypoxia-induced apoptosis of cardiomyocytes. Here, we attempted to intervene in the AGS8-G beta gamma signaling process and protect cardiomyocytes from hypoxia-induced apoptosis with a peptide that disrupted the AGS8-G beta gamma interaction. Synthesized AGS8-peptides, with amino acid sequences based on those of the G beta gamma-binding domain of AGS8, successfully inhibited the association of AGS8 with G beta gamma. The AGS8-peptide effectively blocked hypoxia-induced apoptosis of cardiomyocytes, as determined by DNA end-labeling and an increase in cleaved caspase-3. AGS8-peptide also inhibited the change in localization/permeability of channel protein connexin 43, which was mediated by AGS8-G beta gamma under hypoxia. Small compounds that inhibit a wide range of G beta gamma signals caused deleterious effects in cardiomyocytes. In contrast, AGS8-peptide did not cause cell damage under normoxia, suggesting an advantage inherent in targeted disruption of the AGS8-G beta gamma signaling pathway. These data indicate a pivotal role for the interaction of AGS8 with G beta gamma in hypoxia-induced apoptosis of cardiomyocytes, and suggest that targeted disruption of the AGS8-G beta gamma signal provides a novel approach for protecting the myocardium against ischemic injury.

DOI： 10.1371/journal.pone.0091980

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記述言語：日本語   出版者・発行元：(一社)日本ハイパーサーミア学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PUBLIC LIBRARY SCIENCE  

Store-operated Ca2+ entry (SOCE) is a major mechanism of Ca2+ import from extracellular to intracellular space, involving detection of Ca2+ store depletion in endoplasmic reticulum (ER) by stromal interaction molecule (STIM) proteins, which then translocate to plasma membrane and activate Orai Ca2+ channels there. We found that STIM1 and Orai1 isoforms were abundantly expressed in human melanoma tissues and multiple melanoma/melanocyte cell lines. We confirmed that these cell lines exhibited SOCE, which was inhibited by knockdown of STIM1 or Orai1, or by a pharmacological SOCE inhibitor. Inhibition of SOCE suppressed melanoma cell proliferation and migration/metastasis. Induction of SOCE was associated with activation of extracellular-signal-regulated kinase (ERK), and was inhibited by inhibitors of calmodulin kinase II (CaMKII) or Raf-1, suggesting that SOCE-mediated cellular functions are controlled via the CaMKII/Raf-1/ERK signaling pathway. Our findings indicate that SOCE contributes to melanoma progression, and therefore may be a new potential target for treatment of melanoma, irrespective of whether or not Braf mutation is present.

DOI： 10.1371/journal.pone.0089292

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：5  

The aim of this experiment was to evaluate the histological effects of zoledronic acid on the periodontal space in rats. 40 male Wistar rats were divided into three zoledronic acid groups and a control group. Zoledronic acid was injected subcutaneously at doses of 10, 50, or 500 μg/kg once a week for 3 weeks. The rats were killed 1 or 9 weeks after the last injection. Histological examination of the periodontal space around the incisor tooth revealed that zoledronic acid did not inhibit tooth development. In the rats killed 1 week after treatment discontinuation, the periodontal space gradually narrowed in response to increasing zoledronic acid doses, and the changes were statistically significant according to ANOVA but not according to ANOVA with post hoc tests. The changes persisted in the high-dose zoledronic acid group despite zoledronic acid discontinuation, with significant differences identified by ANOVA and ANOVA with post hoc tests. Therefore, although zoledronic acid had an insignificant effect on tooth development, it had a significant effect on the periodontal space when high doses were administered. The results of this experiment may provide useful information for future investigations on the role of zoledronic acid in the osteonecrosis of the jaw. © 2012 International Association of Oral and Maxillofacial Surgeons.

DOI： 10.1016/j.ijom.2012.11.011

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掲載種別：研究論文（学術雑誌）  

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記述言語：英語   出版者・発行元：SPRINGER JAPAN KK  

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記述言語：英語   出版者・発行元：SPRINGER JAPAN KK  

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記述言語：英語   出版者・発行元：SPRINGER JAPAN KK  

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出版者・発行元：American Heart Association, Inc.  

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その他リンク： http://orcid.org/0000-0001-8006-5485

記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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その他リンク： http://orcid.org/0000-0001-8006-5485

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE PHARMACOLOGICAL SOC  

We previously demonstrated that type 5 adenylyl cyclase (AC5) functions in autonomic regulation in the heart. Based on that work, we hypothesized that pharmacological modulation of AC5 activity could regulate the autonomic control of the heart rate under micro- and hypergravity. To test this hypothesis, we selected the approach of activating AC5 activity in mice with a selective AC5 activator (NKH477) or inhibitor (vidarabine) and examining heart rate variability during parabolic flight. The standard deviation of normal R-R intervals, a marker of total autonomic variability, was significantly greater under micro- and hypergravity in the vidarabine group, while there were no significant changes in the NKH477 group, suggesting that autonomic regulation was unstable in the vidarabine group. The ratio of low frequency and high frequency (HF) in heart rate variability analysis, a marker of sympathetic activity, became significantly decreased under micro- and hypergravity in the NKH477 group, while there was no such decrease in the vidarabine group. Normalized HF, a marker of parasympathetic activity, became significantly greater under micro- and hypergravity in the NKH477 group. In contrast, there was no such increase in the vidarabine group. This study is the first to indicate that pharmacological modulation of AC5 activity under micro- and hypergravity could be useful to regulate the autonomic control of the heart rate.

DOI： 10.1254/jphs.12102FP

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：4  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   出版者・発行元：AMER SOC CELL BIOLOGY  

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記述言語：英語   出版者・発行元：(一社)日本循環器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Bentham Science Publishers B.V.  

Cytochrome P450 (CYP) represents a large family of enzymes that catalyze the oxidation of endogenous and exogenous compounds. The functions of CYP enzymes in the metabolism of xenobiotics have well been established in the liver. However, some CYP enzymes are highly expressed in the heart and catalyze arachidonic acid oxidation to a variety of eicosanoids, which attenuates ischemiareperfusion injury of the heart. CYP-mediated cardioprotection is associated with activation of multiple pathways such as sarcolemmal and mitochondrial potassium channels, p42/p44 MAPK and PI3K-AKT signaling in cells. CYP enzymes also represent a significant source of reactive oxygen species (ROS) that may target cellular homeostatic mechanisms and mitochondria. CYP isoforms expressed in the heart are critical for generation of epoxyeicosatrienoic acids (EETs) and ROS. It has been demonstrated that CYP2J2 generates cardioprotective EETs, whereas another isozyme in the heart, CYP2C, generates EETs as well as detrimental ROS. Genetic polymorphisms of CYP2C or CYP2J2 have a pathologic impact on coronary artery diseases. Cardiac CYP enzymes can be involved in drug metabolism within the heart and influence pharmacologic efficacy. Metabolism mediated by CYP enzymes influences the survival of cardiomyocytes during ischemia, which is critical for treatment of human ischemic heart disease. In this review, we summarize current knowledge of this enzyme family and discuss the roles of CYP in ischemia-reperfusion injury of the heart. © 2011 Bentham Science Publishers Ltd.

DOI： 10.2174/138920011795713715

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記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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記述言語：英語   出版者・発行元：2  

The G-protein signaling system plays an important role in controlling cellular responses to numerous hormones and neurotransmitters involved in homeostasis of the cardiovascular system. In addition to traditional determinants of G-protein signaling such as the G-protein-coupled receptor (GPCR), heterotrimeric G-proteins and effectors, accumulating data indicate the existence of entities that directly regulate the activation status of G-proteins independent of GPCR. To date, there have been a number of reports on accessory proteins that influence GDP dissociation, affect nucleotide exchange at the Gα subunit, alter subunit interactions within heterotrimeric Gαβγ independent of nucleotide exchange, or form complexes with Gα or Gβγ independent of the typical Gαβγ heterotrimer. Such proteins may provide an additional signal input to the G-protein signaling system in the absence of GPCR or may act as an alternative binding partner of G-protein subunits serving unknown roles of G-proteins in cells. Accumulating information suggests that accessory proteins for G-proteins are actually involved in the regulation of the signaling system to maintain homeostasis and the dynamic responses to physiological and pathological challenges. It is likely that alterations in signal processing may be achieved by the modulation of signal processing within the cell using accessory proteins for G-proteins. The loss of regulation of this system, leading to inappropriate activation or inactivation of G-protein signaling, is strongly implicated in various human diseases. In this review, we update current information and discuss different accessory proteins for heterotrimeric G-proteins in terms of their involvement in the regulation of the cardiovascular system. Such information may contribute to uncovering mechanisms underlying cardiovascular disease as well as the development of novel therapeutic approaches to human disease. © 2009 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.pathophys.2009.03.011

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記述言語：英語   出版者・発行元：(一社)日本循環器学会  

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記述言語：英語   出版者・発行元：SPRINGER TOKYO  

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記述言語：英語   出版者・発行元：SPRINGER TOKYO  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER IRELAND LTD  

A 40-year-old man was referred to our hospital because of an abnormal shadow on the left cardiac border on the chest roentgenogram at the regular medical health examination without any symptoms. A giant coronary artery aneurysm of left anterior descending artery with a maximum diameter of approximately 50 mm was detected with computed tomography and coronary angiography. The patient was treated and followed up medically. Four years later, the size of the coronary artery aneurysm became larger. Then resection of the coronary artery aneurysm and coronary artery bypass grafting were successfully performed. Coronary artery aneurysms are rare in adults and are usually found in association with Kawasaki disease, coronary atherosclerosis, and so on. We also review the literature of giant coronary artery aneurysms exceeding 50 mm in diameter. (C) 2008 Japanese College of Cardiology. Published by Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.jjcc.2008.07.015

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記述言語：英語   出版者・発行元：(一社)日本循環器学会  

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記述言語：英語   出版者・発行元：JAPANESE PHARMACOLOGICAL SOC  

Cyclic AMP (cAMP) is known to play a major role in regulating cardiac function. Difference in adenylyl cyclase (AC) isoforms is a potential mechanism by which the cAMP signal, a common second messenger signal, can be regulated in a tissue-specific manner. However, the physiological significance of expressing multiple AC isoforms in a tissue and how each specific isoform regulates the cAMP signal remains poorly understood. In a genetically engineered mouse model in which the expression of the type 5 AC is knocked out (AC5KO), we identified the attenuation of autonomic regulation and calcium-mediated inhibition of cardiac function. We also identified that disruption of type 5 AC preserves cardiac function in response to chronic pressure-overload and catecholamine stress, at least in part, through the inhibition of cardiac apoptosis, which plays a major role in the development of heart failure. The protection against both apoptosis and development of cardiac dysfunction induced by left ventricular pressure overload in AC5KO makes this molecule potentially important for developing future pharmacotherapy, where suppressing the activity of type 5 AC, and not the entire beta-adrenergic signaling (beta-AR) signaling pathway, may have an advantage over the current beta-AR-blockade therapy in the treatment of heart failure.

DOI： 10.1254/jphs.08R26FM

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記述言語：英語   出版者・発行元：(一社)日本循環器学会  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japanese Journal of Cancer and Chemotherapy Publishers Inc.  

We report a patient who long had a complete response by chemotherapy with imatinib mesilate (IM) for locally recurrent gastrointestinal stromal tumor (GIST) of the stomach. On July 2000, a 58-year-old woman was pointed out to have anemia in the course of surveillance for malignant melanoma of skin. Endoscopic examination revealed continuous bleeding from a submucosal tumor with ulceration on the posterior wall of the stomach. After endoscopic hemostasis failed, emergency laparotomy was performed and a biopsy was also done. The diagnosis made was GIST from immunohistological findings of positive c-kit, positive CD34, negative HMB45, and negative S100. After diagnosis, total gastrectomy, distal pancreatectomy, and splenectomy were performed. On September 2003, a local recurrence was recognized, and then chemotherapy by 400 mg IM daily was started. After beginning with a dose of IM 400 mg daily, the reduction of the tumor was monitored. The IM dose then had to be reduced to 300 mg daily. Because of the adverse side effects of IM, systemic edema and body weight increased. After reduction of IM, the adverse reactions resolved promptly, and a complete response of the primary tumor has been maintained for 4 years 3 months.

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記述言語：英語   出版者・発行元：SPRINGER TOKYO  

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記述言語：英語   出版者・発行元：SPRINGER TOKYO  

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記述言語：英語   出版者・発行元：CHURCHILL LIVINGSTONE INC MEDICAL PUBLISHERS  

DOI： 10.1016/j.cardfail.2008.07.174

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記述言語：英語   出版者・発行元：(NPO)日本小児循環器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：4  

We experienced five cases of pulmonary arteriovenous malformations (PAVMs) that were successfully treated by video-assisted thoracoscopic surgery. Four malformations were treated by local wedge resection and one was treated by segmentectomy. Criteria for patient selection for surgery were peripheral and solitary lesions, with feeding arteries larger than 3 mm. Postoperative hospital stays were 1-7 days (median, 2 days). All patients showed unchanged or increased values of PaO2 in arterial blood after operation. No major postoperative complication occurred in any patient, but a persistent air leak for 5 days occurred in the one patient who was treated by segmentectomy. No growth of accessory vessels or untreated malformations were seen in any patient throughout the follow-up period of 14-54 months. Thoracoscopic surgical resection for well-selected patients provides a high certainty of eliminating fistulae and was associated with lower morbidity, lower mortality, and shorter hospital stays. © 2008 The Japanese Association for Thoracic Surgery.

DOI： 10.1007/s11748-007-0215-6

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記述言語：英語   出版者・発行元：FEDERATION AMER SOC EXP BIOL  

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記述言語：英語   出版者・発行元：(一社)日本生理学会  

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記述言語：英語   出版者・発行元：(一社)日本生理学会  

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記述言語：英語   出版者・発行元：(一社)日本生理学会  

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記述言語：英語   出版者・発行元：(一社)日本循環器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：INT PEDIATRIC RESEARCH FOUNDATION, INC  

Neointimal cushion formation (NCF) is an important vascular remodeling for anatomical closure of the ductus arteriosus (DA). Inflammatory responses to vascular injury or atherosclerosis are known to be associated with the pathogenesis of NCF. We found that the expression of interleukin (IL)-15 mRNA was significantly higher in rat DA than in the aorta. IL-15 immunoreactivity was detected predominantly in the internal elastic laminae (IEL) and to a lesser extent in smooth muscle cells (SMCs) in rat DA. Prostaglandin E (PGE) increased the expression of IL-15 mRNA in cultured DA SMCs. IL-15 significantly attenuated the platelet-derived growth factor (PDGF)-BB-mediated SMC proliferation, but did not change SMC migration. IL-15 significantly attenuated PGE(1)-induced hyaluronic acid (HA) production in a dose-dependent manner, which is a potent stimulator of NCF. Accordingly, IL-15 might have an inhibitory effect on the physiologic vascular remodeling processes in closing the DA.

DOI： 10.1203/PDR.0b013e31813c9339

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSIOLOGICAL SOC  

Retinoic acid (RA), a metabolite of vitamin A, has been proposed to regulate vascular remodeling and reactivity of the ductus arteriosus (DA). Using rat Affymetrix GeneChips, we found that a considerable number of genes in DA varied their expression levels in accordance with developmental mode: namely, preterm-, term-, and postnatal-dominant clusters. Among a total of 8,740 probe sets, maternal vitamin A administration (MVA) changed the expression levels of 91 genes (116 probe sets) >2.5-fold. About half of preterm-and term-dominant genes responded to MVA, whereas only 5% of postnataldominant genes responded to MVA, indicating that fetal-dominant genes were susceptible to RA signals. The expression levels of 51 genes in MVA-treated DA at preterm were similar to the expression levels in nontreated DA at term, indicating that the global gene profile at preterm resembled that of the control animal at term. We observed neointima formation in MVA-treated DA at preterm in accordance with upregulation of fibronectin and hyaluronic acid, whereas it was rarely observed in nontreated DA at preterm. Five fetal cardiac myofibrillar genes were also upregulated in MVA-treated in vivo DA, whereas they were developmentally downregulated in nontreated DA. The present study indicates that MVA-mediated alteration in gene profile was associated with early structural maturation of DA, although MVA-mediated maturation may differ from normal vascular remodeling of DA.

DOI： 10.1152/physiolgenomics.00007.2006

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出版者・発行元：3  

DOI： 10.2174/187231207781369744

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記述言語：英語   出版者・発行元：(一社)日本生理学会  

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記述言語：英語   出版者・発行元：(一社)日本循環器学会  

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記述言語：英語   出版者・発行元：(一社)日本循環器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CAROL DAVILA UNIV PRESS  

Caveolin, a major protein component of caveolae, directly interacts with multiple signaling molecules, such as Ras and growth factor receptors, and inhibits their function. However, the role of the second messenger system in mediating this inhibition by caveolin remains poorly understood. We examined the role of Ca2+-dependent signal in caveolin-mediated growth inhibition using a rat cardiac myoblast cell line (H9C2), in which the expression of caveolin-3, the muscle specific subtype, can be induced using the LacSwitch system. Upon induction with IPTG and serum-starvation, the expression of caveolin-3 was increased by 3.3-fold relative to that of mock-induced cells. The recombinant caveolin-3 was localized to the same subcellular fraction as endogenous caveolin-3 after sucrose gradient purification. Angiotensin II enhanced ERK phosphorylation, but this enhancement was significantly decreased in caveolin-3-induced cells in comparison to that in mock-induced cells. Similarly, when cells were stimulated with fetal calf serum, DNA synthesis, as determined by [H-3]-thymidine incorporation, was significantly decreased in caveolin-3 -induced cells. When cells were treated with Ca2+ chelator (BAPTA and EGTA), however, this attenuation was blunted. Calphostin (PKC inhibitor), but not cyclosporine A treatment (calcineurin inhibitor), blunted this attenuation in caveolin-3 induced cells. Our findings suggest that caveolin exhibits growth inhibition in a Ca2+-dependent manner, most likely through PKC, in cardiac myoblasts.

DOI： 10.1111/j.1582-4934.2006.tb00302.x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：W B SAUNDERS CO  

DOI： 10.1053/j.jvca.2005.06.009

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Sarcolipin. a homologue of phospholamban, regulates Ca2+ uptake through the interaction with sarcoplasmic reticulum Ca2+ ATPase (SERCA) and is predominantly expressed in the atrial muscle. Although the atria] chamber-specific expression of sarcolipin could be primarily regulated at the transcriptional level, the transcriptional regulation remains poorly understood. Since mechanical stress plays all important role in transcriptional regulation of a gene involved in cardiac hypertrophy and remodeling, we generated left-sided or right-sided pressure-overload models by transverse aortic constriction (TAC) in ddY mice or by monocrotaline administration in Wistar rats. respectively. TAC significantly decreased the expression of sarcolipin, SERCA2a, and phospholamban ,RNAs in the left atrium (LA) than those in the right atrium (RA). By contrast, monocrotaline administration significantly decreased the expression of sarcolipin. SERCA2a. and phospholamban mRNAs in the RA than those in the LA. The two independent complementary experiments unequivocally demonstrated that mechanical stress down-regulates the transcription of the sarcolipin gene. (c) 2005 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2005.06.186

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The two stimulatory G protein alpha subunits, Gas and Galphaolf, activate adenylyl cyclase in a similar way. We examined whether type 5 adenylyl cyclase knockout, the major striatal isoform, can differentially and/or developmentally change the expression of these G proteins in the striatum. Galphas and Galphaolf expressions at birth were unaffected in knockouts, which, however, demonstrated a blunted developmental increase in Galphaolf, but not Galphas. Adenylyl cyclase activity was unaffected at birth, but subsequently became lower in knockouts. These findings suggest that type 5 adenylyl cyclase does not contribute to striatal cAMP signaling at birth. However, it may play an important role in developmental changes in the expression of Galphaolf, but not Galphas. (C) 2004 Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.

DOI： 10.1016/S0014-5793(04)00333-3

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

We investigated whether polymorphism of the type 6 adenylyl cyclase gene influences the occurrence of left ventricular hypertrophy in a Japanese population. Type 6 adenylyl cyclase is a major cardiac adenylyl cyclase isoform and plays an important role in regulating cardiac function. We examined the type 6 adenylyl cyclase gene for single nucleotide polymorphism by heteroduplex analysis and found a mutation (T11215A) in intron 17. We genotyped the single nucleotide polymorphism (TT/TA/AA groups) by the mutagenically separated polymerase chain reaction method in 2068 subjects who underwent health screening for cardiovascular disease. Genetic variation was in the Hardy-Weinberg equilibrium. We found no significant association between the frequency of left ventricular hypertrophy and any of the genotype groups. In the TT and the TA genotype group, however, left ventricular hypertrophy was associated with increased blood pressure, while no association with increased blood pressure was found in the AA genotype group. It was concluded that the AA group may be at risk of developing left ventricular hypertrophy independent of increased blood pressure.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

Preconditioning enables endogenous protection to repeated myocardial ischemia. However, the effect of preconditioning on beta1 adrenergic receptor (AR) signal remains controversial. We have recently developed receptor assay system using whole cells, in which overexpressed cell surface beta ARs can be readily quantitated without disrupting the cell. Using this technique, we examined the effects of chemical/metabolic ischemia on the beta1 AR sequestration and adenylyl cyclase activity. Isoproterenol treatment, but not forskolin treatment, of HEK293T cells overexpressing beta1 ARs led to a rapid decrease (within 2 hours) in the number of the cell surface receptor, which was negated in the presence of concanavalin A. Similarly, treatment of cells with potassium cyanide and 2-deoxy-D-glucose (chemical/metabolic ischemia) induced similar receptor sequestration. When isoproterenol was superimposed on chemical/metabolic ischemia, the degree of sequestration became greater. However. when cells were pre-exposed to potassium cyanide on the preceding day (chemical preconditioning), the sequestration induced by either isoproterenol or chemical/metabolic ischemia was attenuated. Adenylyl cyclase catalytic activity as assessed by stimulation with forskolin was decreased by chemical/metabolic ischemia but fully recovered after 24 hours, suggesting that chemical/metabolic ischemia treatment did not alter cell viability. Putting together, chemical/metabolic ischemia induced betal AR sequestration in a similar manner to isoproterenol. In addition, preconditioning prevented the betal AR sequestration induced by both isoproterenol and chemical/metabolic ischemia. Pre-conditioning may play a role in preserving the cell surface beta ARs by inhibiting the sequestration that is usually induced by an ischemic event or beta adrenergic stimulation. (C) 2003 Published by Elsevier Ltd.

DOI： 10.1016/S0022-2828(03)00173-1

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記述言語：英語   出版者・発行元：ASHLEY PUBLICATIONS LTD  

Adenylyl cyclase (AC) is a target enzyme of multiple G-protein-coupled receptors (GPCRs). In the past decade, the cloning, structure and biochemical properties of nine AC isoforms were reported, and each isoform of AC shows distinct patterns of tissue distribution and biochemical/pharmacological properties. In addition to the conventional regulators of this enzyme, such as calmodulin (CaM) or PKC, novel regulators, for example, caveolin, have been identified. Most importantly, these regulators work on AC in an isoform-dependent manner. Recent studies have demonstrated that certain classic AC inhibitors, i.e., P-site inhibitors, show an isoform-dependent inhibition of AC. The side chain modifications of forskolin, a diterpene extract from Coleus forskolii, markedly enhance its isoform selectivity. When taken together, these findings suggest that it is feasible to develop new pharmacotherapeutic agents that target AC isoforms to regulate various neurohormonal signals in a highly tissue-/organ-specific manner.

DOI： 10.1517/14728222.7.3.441

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Numerous attempts have been made to develop strategies for regulating the intracellular cyclic AMP signal pharmacologically, with an intention to establish either new medical therapeutic methods or experimental tools. In the past decades, many pharmacological reagents have been identified that regulate this pathway at the level of the receptor, G protein, adenylyl cyclase, cyclic AMP, protein kinase A and phosphodiesterase. Since the cloning of adenylyl cyclase isoforms during the 1990s, investigators including ourselves have tried to find reagents that regulate the activity of this enzyme directly in an isoform-dependent manner. The ultimate goal of developing such reagents would be to regulate the cyclic AMP signal in an organ-dependent manner. Ourselves and other workers have reported that such reagents may vary from a simple cation to kinases. In a more recent study, using the results from crystallographic studies and computer-assisted drug design programs, we have identified subtype-selective regulators of adenylyl cyclase. Such regulators are mostly based upon forskolin, a diterpene compound obtained from Coleus forskolii, that acts directly on adenylyl cyclase to increase the intracellular levels of cyclic AMP. Similarly, novel reagents have been identified that inhibit a specific adenylyl cyclase isoform (e.g. type 5 adenylyl cyclase). Such reagents would potentially provide a new therapeutic strategy to treat hypertension, for example, as well as methods to selectively stimulate or inhibit this adenylyl cyclase isoform, which may be reminiscent of overexpression or knocking out of the cardiac adenylyl cyclase isoform by the use of a pharmacological method.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Upon agonist binding, beta-adrenergic receptors sequestrate from the cell surface plasma membrane to cytosol. In the present study, we examine the kinetics of sequestration of beta(1)-adrenergic receptor and beta(3)-adrenergic receptor subtypes by radioligand binding assays using whole cells ('whole cell binding assays'). We found that HEK293T cells, but not COS1 cells, were readily and uniformly detached from the culture dish upon exposure to ice-cold phosphate-buffered saline. Using this property of HEK293T cells, we conducted whole cell binding assays using a hydrophilic antagonist ([H-3]CGP-12177) and HEK293T cells transiently overexpressing human beta(1)-adrenergic receptor or beta(3)-adrenergic receptor. The B-max and K-d values were 5.96 +/- 0.97 pmol/mg protein and 1 +/- 0.23 nM for the beta(1)-adrenergic receptor, and were 1.84 +/- 0.13 pmol/mg protein and 44.7 +/- 2.5 nM for the beta(3)-adrenergic receptor, respectively. Isoproterenol treatment, but not 6-[3-(dimethylamino)propionyl]forskolin treatment, for 2 h resulted in a dose-dependent loss of the number of the cell surface beta(1)-adrenergic receptor. At 100 muM, 36.6 +/- 5.7% of the cell surface beta(1)-adrenergic receptor was lost. In contrast, the cell surface beta(3)-adrenergic receptor number remained unchanged with isoproterenol treatment. Thus, beta(1)-adrenergic receptor sequestrates upon agonist stimulation but the same agonist stimulation does not induce beta(3)-adrenergic receptor sequestration, as demonstrated by our whole cell binding assays.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

We examined the effects of diabetes on the morphological features and regenerative capabilities of adult mouse nodose ganglia (NG) and dorsal root ganglia (DRG). By light and electron microscopy, no apoptotic cell death was detected in the ganglia obtained from either streptozotocin (STZ)-induced diabetic or normal C57BL/6J mice in vivo. Neurite regeneration from transected nerve terminals of NG and DRG explants in culture at normal (10 mM) and high (30 mM) glucose concentrations was significantly enhanced in the diabetic mice. Chromatolytic changes (i.e. swelling and migration of the nucleus to an eccentric position in the neurons, and a loss of Nissl substance in the neuronal perikarya) and apoptotic cell death (less than one-fifth of the neurons) in the cultured ganglia were present, but neither hyperglycemia in vivo nor high glucose conditions in vitro altered the morphological features of the ganglia or the ratios of apoptotic cells at 3 days in culture. By semiquantitative RT-PCR analysis, the mRNA expressions of ciliary neurotrophic factor (CNTF) in DRG from both mice were down-regulated at I day in culture. The expression in diabetic DRG, but not in control DRG, was significantly up-regulated at later stages (3 and 7 days) in culture. In summary, hyperglycemia is unlikely to induce cell death in the sensory ganglia, but enhances the regenerative capability of vagal and spinal sensory nerves in vitro. The up-regulation of CNTF mRNA expression during the culture of diabetic DRG may play a role in the enhanced neurite regeneration. (C) 2002 Elsevier Science Inc. All rights reserved.

DOI： 10.1016/S0024-3205(02)02040-4

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate whether or not cardiac sympathetic nerve activity, using (123)I-meta-iodobenzylguanidine ((123)I-MIBG) imaging, and cardiac natriuretic peptides (atrial and brain, ANP and BNP) were independent predictors of cardiac events, and, if so, which was the stronger predictor. Planar (123)I-MIBG images were obtained from 62 patients with heart disease. Plasma ANP and BNP levels, left ventricular ejection fraction (LVEF) by echocardiography, serum total cholesterol and triglyceride were measured. (123)I-MIBG was assessed as the heart-to-mediastinum (H/M) ratio of the delayed image and the washout rate (WoR) from the early to the delayed image. Patients were followed up for an average of 16.2 months, and 12 of 62 patients had cardiac events. Patients with events had significantly lower LVEF and H/M ratio compared with those without events. They had significantly higher WoR, ANP and BNP. By multivariate Cox proportional hazard analysis, (123)I-MIBG (H/M or WoR), ANP and BNP were independent predictors for cardiac events. Event-free survival using a Kaplan-Meier model, with a threshold value of 2.0 for H/M and 45% for WoR, showed that patients with H/M<2.0 and/or WoR>45% had a significantly poorer prognosis. These results suggest that (123)I-MIBG imaging and cardiac natriuretic peptides are useful tools for the evaluation of patients with heart disease, and that cardiac sympathetic nerve activity is a stronger predictor of cardiac events.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

Trachea is intensely innervated with vagal afferent nerve fibers, and may play an important role in vagus nerve regeneration after axonal injury caused by trauma and surgical operation. We investigated the effects of tracheal tissue on neuronal cell survival and neurite regeneration in adult rat nodose ganglia (NG) in vitro. Co-culture with trachea significantly increased the average number of neurites regenerated frown transected nerve terminals of NG explants, from 73.7 to 154.2 after 3 days, from 58 to 186.7 after 5 days, and from 31 to 101.5 after 7 days in culture. Dissociated NG neurons could continue to survive and extend neurites only in the co-existence with satellite cells in collagen gel. Co-cultured trachea improved the ratios of survival and neurite-bearing cells of NG neurons, from 56.7% and 11.1% to 72.3% and 37.6% after 4 days, and from 41.1% and 20.3% to 56.4% and 47.2% after 7 days in culture, respectively. These results imply that tracheal tissue secretes a factor, which could enhance neuronal cell survival and neurite regeneration in NG in the presence of satellite cells in vitro. (C) 2002 Elsevier Science Inc. All rights reserved.

DOI： 10.1016/S0024-3205(02)01498-4

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI IRELAND LTD  

it is now accepted that caveolin plays a key role in signal transduction by directly binding to and regulating the function of molecules involved in transmembrane signaling, such as ras, suggesting that the amount of caveolin within cells may be an important factor in determining the cellular signaling. We investigated the ontogenic changes in the protein amount of caveolin subtypes, as well as ras protein expression in various organs (the heart, lungs, and muscles) obtained from aging rats (neonates, young and old adults). Our results demonstrated that caveolin protein expression changed ontogenically in a subtype-dependent manner. In lungs, for example, caveolin-1 expression changed in an opposite manner to caveolin-3 expression. while in the heart caveolin-1 and -3 changed in parallel. Ras expression showed an ontogenic increase in lungs and a decrease in muscles, which were both parallel to caveolin-1 expression. Our results suggest that the regulation of transmembrane signaling by caveolin may differ among developmental stages and caveolin subtypes. (C) 2001 Elsevier Science Ireland Ltd. Ail rights reserved.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Interleukin-6 (IL-6) is a neurotrophic cytokine, however, its direct effect on nerve regeneration has not been well characterized. We therefore examined the effect of IL-6 on neurite regeneration using the rat dorsal root ganglion. IL-6 significantly enhanced neurite regeneration from transected nerve terminals. We also examined the mRNA expression of IL-6 family cytokines and their receptors during the regeneration. The mRNA expressions of IL-6, IL-6 receptor, leukemia inhibitory factor (LIF), ciliary neurotrophic factor (CNTF) receptor alpha, and LIF receptor beta showed no significant differences by the addition of IL-6. In contrast, IL-6 enhanced the mRNA expression of gp 130 and CNTF. In addition, CNTF significantly increased neurite regeneration when added exogenously. Our data suggest that IL-6 enhanced regeneration via up-regulating CNTF expression. NeuroReport 12:1081-1085 (C) 2001 Lippincott Williams & Wilkins.

DOI： 10.1097/00001756-200104170-00043

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI IRELAND LTD  

To determine the role of cytokines in the nervous system, we examined the effect of interleukin-12(IL-12) on the nerve regeneration of mouse superior cervical ganglion cells (SCG). IL-12 enhanced the neurite outgrowth in a concentration-dependent manner. Immunocytochemical studies demonstrated the expression of IL-12 receptors in neuronal bodies and neurites. The mRNA expression of IL-12 receptors in SCG cells was confirmed by reverse transcription-polymerase chain reaction. Our data demonstrated the presence of IL-12 receptors in sympathetic neurons and suggest that IL-12 plays an important role in neuronal regeneration, (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.

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We examined the effect of experimental diabetes on neurite regeneration from adult mouse retinal explants cultured in the presence of different concentrations of glucose. The numbers of regenerating neurites at 3, 6 and 10 days in culture at normal glucose concentration (7 mM) were significantly smaller in streptozotocin-induced diabetic C57BL/6 mice than in normal control mice. In contrast, treatment of retinal explants with high glucose concentration (57 mM) significantly diminished the number of regenerating neurites in the control mice, but not in the diabetic mice. These results suggest that retina in diabetic mice has impaired capability of neurite regeneration in a normal glucose environment, but is adaptable to a high glucose environment in vitro. Copyright (C) 1999 Elsevier Science Ireland Ltd.

DOI： 10.1016/S0304-3940(99)00768-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

THIS study examined the effect of diabetes on neural regeneration in vitro. Nodose ganglia (NG) with vagal nerve fibers, dissected from streptozotocin-induced diabetic and normal C57BL/6J mice were embedded in collagen gel. After 3 and 7 days in culture, the numbers of regenerating neurites from transected nerve terminals of NG in diabetic mice were significantly greater than those in controls. Although many studies have revealed diabetes-associated impairment in neural regeneration, the results in the present study suggest that experimental diabetes could induce the potential to enhance regenerative capability of vagal sensory nerves after axotomy. NeuroReport 10:1025-1028 (C) 1999 Lippincott Williams & Wilkins.

DOI： 10.1097/00001756-199904060-00024

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

Recent data have demonstrated that caveolin, a major structural protein of caveolae, inhibits the function of molecules involved in cAMP signaling such as adenylyl cyclase. We examined the effect of cAMP signal on the expressions of caveolin subtypes using rat cardiac myoblasts (H9C2 cells) and smooth muscle cells (RASMC), which express caveolin subtypes. Treatment of RASMC and H9C2 cells with forskolin, an adenylyl cyclase stimulator, decreased caveolin-1 mRNA levels in a dose-dependent manner. Time course studies showed a time-dependent decrease of caveolin-1 mRNA levels in H9C2 cells (after 6 hours) while caveolin-1 mRNA levels in RASMC showed a biphasic response, i.e., an initial increase (within 3 hours) and a later decrease (after 3 hours). Similar biphasic changes were observed when RASMC was treated with IBMX, a phosphodiesterase inhibitor. The levels of caveolin-1 and -3 proteins were also decreased by forskolin treatment, but only after 60-72 hours in RASMC and 24-36 hours in H9C2 cells. In contrast, the expression of caveolin-2 remained similar in both cells and decreased to a small degree after prolonged treatment. Therefore, the expression of caveolin is downregulated by cAMP signal in a caveolin subtype-dependent manner.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS INC  

Caveolin is a major structural component of caveolae and has been implicated in the regulation of the function of several caveolae-associated signaling molecules. Platelet-derived growth factor (PDGF) receptors and caveolin were colocalized in the same subcellular fraction after sucrose density gradient fractionation of fibroblasts. Additionally, we found that the PDGF receptors interacted with caveolin in NIH3T3 fibroblast cells. We then examined whether caveolin directly binds to PDGF receptors and inhibits kinase activity using a recombinant PDGF receptor overexpressed in insect cells and peptides derived from the scaffolding domain of caveolin subtypes. We found the peptide from caveolin-1 and -3, but not -2, inhibited the autophosphorylation of PDGF receptors in a dose-dependent manner. Similarly, caveolin-1 and -3 peptides directly bound to PDGF receptors. Mutational analysis using a series of truncated caveolin-3 peptides (20-, 17-, 14-, and 11-mer peptides) revealed that at least 17 amino acid residues of the peptide were required to inhibit and directly bind to PDGF receptors. Thus, our findings suggest that PDGF receptors directly interact with caveolin subtypes, leading to the inhibition of kinase activity. Caveolin may be another regulating factor of PDGF-mediated tyrosine kinase signaling. (C) 1999 Academic Press.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

Recent data have demonstrated that caveolin, a major structural protein of caveolae, negatively regulates signaling molecules localized to caveolae, The interaction of caveolin with several caveolae-associated signaling proteins is mediated by the binding of the scaffolding region of caveolin to a hydrophobic amino acid-containing region within the regulated proteins. The presence of a similar motif within the insulin receptor kinase prompted us to investigate the caveolar localization and regulation of the insulin receptor by caveolin, We found that overexpression of caveolin-3 augmented insulin-stimulated phosphorylation of insulin receptor substrate-1 in 293T cells but not the phosphorylation of insulin receptor. Peptides corresponding to the scaffolding domain of caveolin potently stimulated insulin receptor kinase activity toward insulin receptor substrate-1 or a Src-derived peptide in vitro and in a caveolin subtype-dependent fashion. Peptides from caveolin-2 exhibited no effect, whereas caveolin-1 and -3 stimulated activity 10- and 17-fold, respectively. Peptides which increased insulin receptor kinase activity did so without affecting insulin receptor auto-phosphorylation. Furthermore, the insulin receptor bound to immobilized caveolin peptides, and this binding was inhibited in the presence of free caveolin-3 peptides. Thus, we have identified a novel mechanism by which the insulin receptor is bound and activated by specific caveolin subtypes, Furthermore, these data define a new role for caveolin as an activator of signaling.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

The current study was undertaken to examine whether we can target adenylyl cyclase to regulate P-adrenergic signaling with increased cardiac selectivity. Forskolin, a natural diterpene compound, interacts directly with adenylyl cyclase. We studied the adenylyl cyclase isoform-selectivity of forskolin derivatives using insect cell membranes overexpressing type II, III, and V adenylyl cyclase isoforms. 6-[3-(dimethylamino) propionyl] forskolin (NKH477) stimulated type V more potently (1.87+/-0.02-fold) than type II (1.04+/-0.02-fold) and type III (0.89+/-0.03-fold) relative to forskolin (50 mu M, P&lt;0.05). Similarly, 6-[3-(dimethylamino)propionyl]-14,15-dihydro-forskolin (DMAPD) stimulated type V (1.39+/-0.02-fold) more potently than types II (0.66+/-0.02-fold) and type III (0.31+/-0.02-fold) relative to forskolin (P&lt;0.05). This selectivity was maintained under different assay conditions - i.e. with different forskolin (0.1-100 mu M) and Mg (1-10 mM) concentrations, with or without Gs alpha. NKH477 increased cAMP accumulation in HEK293 cells stably overexpressing type V more than forskolin (1.57+/-0.13-fold) (P&lt;0.05). Examination of multiple tissue homogenates revealed that DMAPD and NKH477 stimulated cardiac adenylyl cyclase more potently than the other tissue adenylyl cyclases (lung, brain, and kidney) relative to forskolin. Our results suggest that a particular side-chain modification of forskolin enhanced the selectivity for the cardiac isoform stimulation. Adenylyl cyclase isoforms may be targeted to increase tissue selectivity in future drug therapy for B-adrenergic regulation. (C) 1998 Academic Press Limited.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

We examined the effect of n-alkanols on adenylyl cyclase isoforms (types II and V) overexpressed in insect cells. Ethanol stimulated the type II isoform but not the type V isoform. Ethanol stimulated type II adenylyl cyclase greater than GTP gamma S, and the treatment of the membrane with GDP beta S or cholera toxin did not affect this stimulation. Other n-alkanols inhibited type V adenylyl cyclase activity in proportion to their lipophilic potency. In contrast, type II adenylyl cyclase was stimulated by weakly lipophilic n-alkanols and inhibited by strongly lipophilic n-alkanols. When solubilized membranes and purified preparations were used, all the n-alkanols inhibited type II adenylyl cyclase. Our data suggest that n-alkanols regulated adenylyl cyclase isoform-dependently. Stimulation of the type II isoform was independent from the interaction with Gs alpha but required the presence of an intact membrane structure. Our study may provide another step to understanding how membrane protein subtypes are differentially regulated by n-alkanols. (C) 1997 Wiley-Liss, Inc.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

The primary goal of this study was to compare the effects of isoproterenol which stimulates beta-adrenergic receptors and forskolin, and NKH 477, a water soluble derivative of forskolin, which stimulate adenylyl cyclase in stunned myocardium of conscious pigs, previously instrumented for measurements of left ventricular pressure and dP/dt, arterial pressure, and wall thickening, Ten min of coronary artery occlusion induced transmural reductions in blood now (radioactive microspheres) in subepicardium (-98 +/- 2%) and subendocardium (-99 +/- 1%). Wall thickening (piezoelectric crystals) fell from 2.50 +/- 0.26 mm to -0.26 +/- 0.26 mm and remained depressed at 1.37 +/- 0.19 mm after 20-30 min coronary artery reperfusion, reflecting myocardial stunning. At that time, isoproterenol (0.2 mu g/kg) increased wall thickening in stunned myocardium (+1.40 +/- 0.16 mm, P &lt; 0.05) more than in control (+ 0.71 +/- 0.22 mm), while forskolin elicited the opposite effects. NKH 477 (30 mu g/kg), which does not penetrate the blood-brain barrier, increased systolic wall thickening similarly before (+ 0.95 +/- 0.25 mm) and during (+ 1.01 +/- 0.24 mm) myocardial stunning, The reflex inotropic responses to inferior vena caval occlusion on wall thickening were diminished, P &lt; 0.05, in the stunned myocardium (+ 0.53 +/- 0.05 mm) compared with control (+ 0.95 +/- 0.07 mm). beta-adrenergic receptor density, which was quantitated with I-125-cyanopindolol binding, was increased transmurally in stunned myocardium compared with non-ischemic myocardium (subepicardium: + 23 +/- 5%, subendocardium: + 34 +/- 13%, P &lt; 0.05). Basal and forskolin-stimulated adenylyl cyclase activities were decreased slightly, but significantly, in the stunned subendocardium but not in the subepicardium, while isoproterenol stimulation of adenylyl cyclase activity showed no differences. In summary, paradoxical responses to beta-adrenergic receptor stimulation were observed in stunned myocardium, with pharmacological stimulation with isoproterenol evoking enhanced responses, and neural stimulation with inferior vena caval occlusion eliciting depressed responses, The diminished responses to forskolin in vivo, in stunned myocardium were out of proportion to the biochemical measurements, and may be attributed to neurally mediated cardiac effects of forskolin, since the responses to direct stimulation of adenylyl cyclase by NKH 477 were preserved. (C) 1997 Academic Press Limited.

DOI： 10.1006/jmcc.1997.0377

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

Both epinephrine and manganese are known to stimulate cAMP production in cardiac homogenates. When added together, however, they inhibited adenylyl cyclase catalytic activity. Type V adenylyl cyclase, the major isoform in the heart, was also inhibited when an increasing concentration of epinephrine was added in the presence of manganese, Inhibition was not dependent on the condition of stimulation or preparation of the enzyme. However, this inhibition was abolished in the presence of anti-oxidant. Other catecholamines, including dopamine and isoproterenol, as well as adrenochrome, an oxidized product of epinephrine, similarly inhibited the activity of this enzyme. Kinetic analyses revealed that the K-m for the substrate ATP was unchanged, but the Vmax was significantly decreased, In contrast, type II adenylyl cyclase, a non-cardiac isoform, was resistant to such inhibition by adrenochrome and was somewhat stimulated by it, Thus, catecholamines, when oxidized, directly interacted with adenylyl cyclase in an isoform-specific manner in the absence of G proteins. Our findings suggest that adenylyl cyclase isoforms have different sensitivity to various stresses, including oxidative stress. (C) 1997 Academic Press Limited.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-LISS  

Phorbol ester treatment enhanced the catalytic activity of type II adenylyl cyclase overexpressed in insect cells. In cells coexpressing type II adenylyl cyclase and protein kinase C-alpha, type II adenylyl cyclase catalytic activity was higher even in the absence of phorbol ester treatment; phorbol ester treatment further and markedly enhanced type II adenylyl cyclase catalytic activity. However, this enhancement, either by phorbol ester treatment or by coexpression of protein kinase C-alpha, was lost following membrane solubilization with detergents. This attenuation was unaffected by phosphatase inhibitor or salts. In contrast, membrane solubilization did not affect forskolin-stimulated type II adenylyl cyclase catalytic activity. Purified type II adenylyl cyclase was stimulated by forskolin and Gs alpha, but not by protein kinase C-alpha. Therefore, a specific mammalian protein kinase C isoenzyme can activate type II adenylyl cyclase, bur the mechanism clearly differs from that underlying either Gs alpha- or forskolin-mediated stimulation. (C) 1997 Wiley-Liss, Inc.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Type V adenylyl cyclase (AC) was stably overexpressed in HEK293 cells (293AC-V). Forskolin-stimulated cAMP accumulation in 293AC-V was 5 times as great as that in control cells. PMA, a protein kinase C (PKC) activator, enhanced cAMP accumulation in 293AC-V cells dose-and time-dependently and this enhancement was abolished by staurosporine. Insulin also enhanced cAMP accumulation in 293AC-V cells. Co-transfection of PKC-zeta, but not PKC-alpha, potentiated the effects of insulin. These data suggest that type V AC activity is regulated in cells by PKC isoenzymes through different extracellular stimuli.

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記述言語：日本語   出版者・発行元：公益社団法人 日本薬理学会  

Adenylylcyclase is a membrane bound enzyme that catalyzes the conversion of ATP to cyclic AMP. Studies on the regulation of adenylylcyclase have been hampered by the small amount of this enzyme in the cell as well as by the instability of the catalytic activity. Cloning of multiple adenylylcyclase isoforms (types I though VIII) has indicated the presence of a large enzyme family, which is further subdivided into several smaller groups. Members within the same group share similar biochemical properties. The multiplicity of adenylylcyclase is made through at least three distinct mechanisms. First, each isoform is encoded by a distinct gene. Second, multiple isoforms are generated through possible alternative splicing from the same gene. Third, there is a mechanism to generate a half-molecule of adenylylcyclase via alternative polyadenylation. Overexpression of a distinct isoform in insect cells followed by purification has enabled researchers to examine the role of each specific isoform in vitro. The results have suggested that each isoform is regulated through distinct mechanisms. For example, type I adenylylcyclase is inhibited in the presence of βγ-subunits, while type II is stimulated. Other isoforms such as types V and VI are not affected. On the other hand, G<SUB>iα</SUB> may directly inhibit each adenylylcyclase isoform. Further characterization of adenylylcyclase would be feasible using those clones in the future.

DOI： 10.1254/fpj.103.285

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00080481492?from=CiNii

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL SCIENCE  

1. The localization of alpha-adrenoceptors in the plasma membranes of human kidney were investigated by radioligand binding, using an alpha1-antagonist, [H-3]-bunazosin, and an alpha2-antagonist, [H-3]-rauwolscine.
2. Both the maximum binding (B(max)) and dissociation constant (K(d)) of [H-3]-bunazosin were greater in the cortex than in the medulla. The B(max) of [H-3]-rauwolscine in the medulla was greater than in the cortex.
3. Thus, alpha1-adrenoceptors appeared to be localized predominantly in the cortex, while the alpha2-adrenoceptors were mainly present in the medulla of the human kidney.

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記述言語：英語   出版者・発行元：The Japanese Society of Hypertension  

It is generally acknowledged that heart failure is characterized by several disorders in cardiac autonomic properties, including sympathetic, parasympathetic and baroreceptor responses. Part of the mechanism of altered cardiovascular control and reduced catecholamine responsiveness in heart failure involves changes in end-organ responses mediated via beta adrenergic receptors. We have now determined the changes that occur in these components during the inception of heart failure induced by cardiac pacing. First, we quantitiated the stoichiometry and function of each of the components of the beta-adrenergic signaling pathway, including the receptor itself, Gs and the adenylylcyclase catalyst. Two key abnormalities occur: (1) the receptor uncouples from Gs, as indicated by loss of high affinity agonist binding sites without a change in receptor density; (2) there is an associated loss adenylylcyclase catalytic activity without any change in the concentration or function of the stimulatory GTP-binding protein Gs. To understand, therefore, what factors underlie the loss in adenylylcyclase catalytic activity; <i>i.e</i>., whether these are the results of a reduced concentration of the catalyst or due to its post-translational modification, we first cloned the cardiac isoforms of adenylylcyclase. Two novel adenylylcyclase cDNAs, types V and VI, were identified that share the motif of tandem six-transmembrane spans separated by a large hydrophilic cytoplasmic loop. Our data suggest that a decrease in the content of the adenylylcyclase catalyst itself contributes to impaired cyclic AMP production in heart failure and may represent a fundamental defect contributing to a progressive decline in LV function. (<i>Hypertens Res</i> 1993; 16: 79-83)

DOI： 10.1291/hypres.16.79

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

A single high affinity binding site for an alpha-2-adrenoceptor in human coronary arteries was identified by radioligand binding assay. Human coronary arteries were obtained at autopsy within 6 hours of death. A crude membrane solution was incubated with (H-3)-rauwolscine at 25-degrees-C for 30 min. The binding of (H-3)-rauwolscine was rapidly saturable and reversible. Kd was 1.2 +/- 0.2 (SE) nM and Bmax 22 +/- 3 fmol/mg protein. This is the first study which has shown the presence of an alpha-2-adrenoceptor in human coronary arteries using a radioligand binding assay method.

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

A direct radioimmunoassay (RIA) for plasma active renin concentration (ARC) was evaluated by using plasma samples obtained from hospitalized normal volunteers and hypertensive patients. The direct renin RIA was performed by using a pair of anti-renin monoclonal antibodies and a sandwich method. It is suggested that an agitator should be used during the incubation, because the magnetic solid phase was precipitated and could not be suspended well in plasmas. Further, the thawed reagents should not be used for the assay. A highly significant correlation (r = 0.96, p &lt
0.01) was found between ARC and enzymatic activity of renin (PRA) in plasma samples obtained from hypertensive patients. The mean values of ARC were 22.8 ± 3.6 pg/ml in normal subjects, 22.5 ± 5.3 in patients with EH having medium levels of PRA, 113.7 ± 11.7 in patients with renovascular hypertension, and undetectable in patients with primary aldosteronism. The results indicated good and reliable performance of the direct renin RIA, which is clinically useful to investigate the renin-angiotensin system.

DOI： 10.1097/00000441-199009000-00002

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Informa Healthcare  

The physiological role of numerically predominant α2 -adrenoceptor in the kidney is still unknown. This study examined the effect of α2zadrenoceptor stimulation on the production of cAMP from isolated human glomeruli. Unaffected portions of human kidneys which had been removed because of renal cell carcinoma were used for the study. Glomeruli were dissected manually under a stereo microscope. In these glomeruli, α2-adrenoceptor stimulation with epinephrine in the presence of propranolol inhibited significantly parathyroid hormone-dependent increases in cAMP production. This inhibitory effect of epinephrine was removed by adding a specific α2-adrenoceptor antagonist, yohimbine, indicating that the inhibitory effect of epinephrine on cAMP formation was due to α2-adrenoceptor stimulation. Thus, α2- -adrenoceptors are involved in the inhibition of cAMP production in human glomeruli. © 1989 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.

DOI： 10.3109/10641968909045431

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MARCEL DEKKER INC  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT-RAVEN PUBL  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The effects of synthetic human atrial natriuretic peptide (ANP) on the release of catecholamines, aldosterone, or cortisol were observed in human adrenal tumors obtained surgically from patients with pheochromocytoma, primary aldosteronism, or Cushing's syndrome, respectively. Each tumor tissue or adjacent normal cortical tissue was sectioned into slices, which were incubated in medium-199 in the presence or absence of adrenocorticotrophin (ACTH) and ANP. The amounts of epinephrine, norepinephrine, aldosterone, or cortisol released into the medium were measured. Existence of ANP receptors on the adrenal tissues was examined by binding assays, affinity labeling, and immunohistochemistry. Release of catecholamines from pheochromocytoma tissues was inhibited by ANP, and the presence of the ANP receptor of phenochromocytoma was further demonstrated by both binding assays and affinity labeling
Scatchard analysis revealed a single class of binding sites for ANP with a K(d) of 1.0 nM and a B(max) of 0.4 pmol/mg of protein and the molecular size was estimated as 140 and a 70 kDa under nonreducing and reducing conditions, respectively. The presence of ANP receptors in phenochromocytoma was demonstrated by immunohistochemistry. ANP inhibited both basal and ACTH-stimulated aldosterone secretion in the slices of normal cortex, and localization of ANP receptors in zona glomerulosa cells was also demonstrated. However, ANP did not inhibit basal and ACTH-stimulated aldosterone and cortisol secretion in both tissue slices from aldosteronoma and Cushing's adenoma. Consistent with these observations, the absence of ANP receptors in adenoma tissues was determined by binding assays, affinity labeling, and immunohistochemistry. In conclusion, we identified the functional ANP receptors in pheochromocytoma and normal zona glomerulosa cells, but not in aldosterone and Cushing's adenoma.

DOI： 10.1097/00005344-198905006-00004

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The effect of synthetic alpha-human atrial natriuretic peptide (ANP) on aldosterone secretion was studied in human aldosterone producing adrenocortical adenoma obtained surgically from a patient with primary aldosteronism and in human apparently normal adjacent adrenal cortical tissues obtained from a patient with pheochromocytoma, in vitro. Apparently normal adrenal cortical tissue responded to ANP with the known inhibition of aldosterone secretion. In contrast, the aldosterone producing adenoma did not respond to ANP. When stimulated by either ACTH or angiotensin II, there is no inhibition by ANP in the adenoma tissue, whereas normal tissue was inhibited. Immunohistochemical examination utilizing an ANP-receptor antiserum demonstrated that there was no evidence of binding site in the cortical adenoma, in contrast, zona glomerulosa cells in the cortical tissues adjacent to either aldosterone producing adenoma or pheochromocytoma were densely stained. This apparent lack of ANP-receptors is an associated finding with the hypersecretion of aldosterone in the aldosterone prducing adenoma. © 1988 Academic Press, Inc.

DOI： 10.1016/S0006-291X(88)80676-4

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Pheochromocytoma, a catecholamine-secreting adrenomedullary tumor, has been shown to contain the functional receptor for human atrial natriuretic peptide(h-ANP). Release of catecholamines from tissue slices of pheochromocytoma was inhibited by h-ANP in a dose-dependent manner. Binding assays using 125I-ANP revealed a single class of high affinity binding sites for ANP. When covalently tagged with 125I-ANP and electrophoresed under non-reducing and reducing conditions, the receptor migrated as a 140-kDa band and a 70-kDa band, respectively, reflecting its disulfide-linked subunit structure. The presence of ANP receptor in pheochromocytoma was further demonstrated by immuno-histochemistry
the tumor was positively stained with an anti-receptor antiserum. The antiserum was also useful to establish the zona glomerulosa localization of ANP receptor in the normal human adrenal gland. © 1987.

DOI： 10.1016/0006-291X(87)91108-9

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：RAPID SCIENCE PUBLISHERS  

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記述言語：日本語   出版者・発行元：(一社)日本Shock学会  

自律神経は生体の持つ基本制御機能であり、交感神経と副交感神経からなる。長い年月をかけた生物の進化過程で獲得された機能であり、ヒトとマウスに基本的な相違はない。このためヒト心不全のモデル動物としてマウスが多用されてきた。ショック状態などの急性心不全では交感神経刺激薬が使用されるが、慢性心不全では反対に交感神経遮断薬が使用される。心機能低下という類似の病態生理にもかかわらず、逆方向の治療が適応される。実は慢性心不全での交感神経遮断薬の使用は、長らく禁忌とされていた。ところが偶然の臨床知見がきっかけとなり、交感神経遮断薬の使用が開始された。今日では日米欧のガイドラインにもβ遮断薬の有効性が収載されている。交感神経遮断薬がどうして慢性心不全に有効であるのかのメカニズムは、興味深いことに臨床知見の後追いとして、基礎実験で証明された。心不全の成因には心臓における交感神経シグナルの特異性が関与しており、この特異性を理解することが交感神経による心機能制御を理解することにつながったと考えられる。(著者抄録)

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本循環制御医学会  

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記述言語：日本語   出版者・発行元：(一社)日本新生児成育医学会  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本病態生理学会  

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記述言語：日本語   出版者・発行元：日本結合組織学会  

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記述言語：日本語  

DOI： 10.2491/jjsth.29.495

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

DOI： 10.11312/ccm.39.155

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本新生児成育医学会  

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記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

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記述言語：日本語   出版者・発行元：(一社)日本周産期・新生児医学会  

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記述言語：日本語   出版者・発行元：日本結合組織学会  

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記述言語：日本語   出版者・発行元：(一社)日本周産期・新生児医学会  

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記述言語：日本語   出版者・発行元：(公社)日本小児科学会  

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記述言語：日本語   出版者・発行元：(一社)日本内分泌学会  

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記述言語：日本語  

J-GLOBAL

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記述言語：英語   出版者・発行元：IEEE  

A novel microfluidic system for applying cyclic pressure to cells during incubation is developed and tested in this work. The cyclic pressure generates stress stimulus to the cells, and is named "Cell Exercise" in this work. The goal of this paper is to design an "On-Chip Cell Gym" where we can observe what happens during the cell exercise in real-time. We design the cell gym on a PDMS chip composed of two parallel chamber arrays, so that we can directly observe the difference with and without Cell Exercise. Cells in one group of chamber is cultured under cell exercise mode and the other one is under none cell exercise mode. Dramatic growth of cell stress fibers is observed in the group of cell exercise with respect to the group without any exercise.

DOI： 10.1109/MEMSYS.2017.7863479

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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記述言語：日本語   出版者・発行元：(一社)日本新生児成育医学会  

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：OXFORD UNIV PRESS  

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記述言語：日本語   出版者・発行元：日本循環制御医学会  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

&lt;p&gt;When we apply cyclic pressure to smooth muscle cells as if humans do muscle training, the cellular tissue becomes stiffer. We call applying such cyclic pressure to cells in order to make stiff cellular tissue &quot;Cell Exercise&quot;. The goal of this study is to understand how cyclic pressure affects cells in microscopic viewpoint. We visualize the behavior of cells under Cell Exercise and under constant pressure, and evaluate the activity of cells with velocity. The transitions of activities have been found different in the two different conditions&lt;/p&gt;

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本周産期・新生児医学会  

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記述言語：日本語   出版者・発行元：(一社)日本生理学会  

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記述言語：日本語   出版者・発行元：(一社)日本生理学会  

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：JAPANESE PHARMACOLOGICAL SOC  

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：JAPANESE PHARMACOLOGICAL SOC  

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：ELSEVIER SCI LTD  

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2015-4548

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2015-4371

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）   出版者・発行元：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2015-4398

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記述言語：日本語   出版者・発行元：(NPO)日本小児循環器学会  

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