Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Although doxorubicin (DOX)-induced cardiomyopathy causes lethal heart failure (HF), no early detection or effective treatment methods are available. The principal mechanisms of cardiotoxicity are considered to involve oxidative stress and apoptosis of cardiomyocytes. However, the effect of DOX on cardiac fibroblasts at non-lethal concentrations remains unknown. The aim of this study was to investigate the direct effect of doxorubicin on the activation of cardiac fibroblasts independent of cell death pathways. We first found that DOX induced α-SMA expression (marker of trans-differentiation) at a low concentration range, which did not inhibit cell viability. DOX also increased MMP1, IL-6, TGF-β and collagen expression in human cardiac fibroblasts (HCFs). In addition, DOX promoted Akt and Smad phosphorylation. A Smad inhibitor prevented DOX-induced α-SMA and IL-6 protein expression. An PI3K inhibitor also prevented MMP1 mRNA expression in HCFs. These findings suggest that DOX directly induces fibrotic changes in HCFs via cell death-independent pathways. Furthermore, we confirmed that these responses are organ- and species-specific for HCFs based on experiments using different types of human and murine fibroblast cell lines. These results suggest potentially new mechanisms of DOX-induced cardiotoxicity from the viewpoint of fibrotic changes in cardiac fibroblasts.

File： Narikawa et al. Doxorubicin induces trans-differentiation and MMP1 expression in cardiac fibroblasts via cell death-independent pathways.pdf

DOI： 10.1371/journal.pone.0221940

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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.

File： EI236.pdf

DOI： 10.1038/srep09194

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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.

File： Store-Operated Ca2+ Entry (SOCE) Regulates Melanoma.pdf

DOI： 10.1371/journal.pone.0089292

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

The ubiquitin ligase NEDD4L participates in plasma Volume and blood pressure regulation by controlling expression of the epithelial sodium channel (ENaC). Genetic impairment of EnaC-Nedd4L-Proteasome system caused a rare mendelian hereditary human hypertension, Liddle syndrome. This finding suggested that Nedd4L is playing an important role in pathogenesis for hypertensive disorders. This prompted us to test a possible involvement of NEDD4L for the development of sodium-sensitive hypertension in Dahl salt-sensitive (DS) rats and its normotensive littermate Dahl salt-resistant (DR) rats. First, we analyzed the transcriptional diversity of rat Nedd4L gene and observed several isoforms with and without calcium-dependent membrane binding (C2) domain at the N-terminal of the protein as we found in human and mouse before. Then, we analyzed the expression of rat NEDD4L in the kidney of both DS and DR under high and low sodium regimens. NEDD4L expression examined by quantitative PCR technique revealed lower expression of NEDD4L transcripts in DS rats under either diet compared to DR animals; additionally, NEDD4L expression was significantly increased with sodium loading. Using in situ hybridization experiments, rat NEDD4L was predominantly expressed in distal nephron in a manner dependent on both sodium regimen and genetic background. A similar histological distribution pattern was observed in human kidney. The expression of NEDD4L in distal nephron and its response to chronic sodium loading suggest that it participates in the functioning of this segment in sodium reabsorption. This response was impaired in genetically sodium-sensitive animals. These findings suggested that Nedd4L gene products were involved in the development of salt-sensitive hypertension. (c) 2005 Elsevier Inc. All rights reserved.

File： Transcriptional diversity and expression of NEDD4L gene in distal nephron..pdf

DOI： 10.1016/j.bbrc.2005.11.120

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Introduction

Connexins are gap junction proteins that play pivotal roles in intercellular communication. Connexin 43 (Cx43) is one of the most ubiquitously expressed connexin isoforms in human. Cx43 has been demonstrated to be involved in the pathological process of various diseases, including arrhythmias. Recently, translationally controlled tumor protein (TCTP), a highly conserved anti-apoptotic protein, has been shown to play an important role in protecting against the development of heart failure. However, its role in arrhythmogenesis remains unclear. In this study, we aimed to examine the interaction between TCTP and Cx43 and investigate the roles of TCTP in the formation of Cx43 gap junction channels and gap junctional intercellular communication (GJIC) in cardiomyocytes.

Methods and results

We found that TCTP was predominantly expressed in the intercalated discs of mouse heart tissue. Cx43 in adult mouse hearts was coimmunoprecipitated using a TCTP-specific antibody. Additionally, co-localization of TCTP and Cx43 was demonstrated using a proximity ligation assay in iPS cell-derived human cardiomyocytes. TCTP silencing reduced the formation of Cx43 gap junction channels at the intercellular contacts between cardiomyocytes. Moreover, TCTP silencing significantly attenuated GJIC among cardiomyocytes. Interestingly, the development of ventricular arrhythmia was attenuated in cardiomyocyte-specific TCTP-overexpressing mice.

Conclusion

These findings indicate that TCTP regulates GJIC. Thus, TCTP may be a therapeutic target for preventing Cx43-related pathogenesis.

DOI： 10.3389/fcell.2025.1549063

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File： Cytotoxic effects of the cigarette smoke extract of heated tobacco products on human oral squamous cell carcinoma.pdf

DOI： 10.1186/s12576-024-00928-1

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File： Methotrexate-Transferrin-Functionalized Fe(Salen)-Polypyrrole Nanocomposites for Targeted Photo-Magneto-Thermal Cancer Treatments.pdf

DOI： 10.3390/jcs6050136

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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.

File： journal.pone.0278613.pdf

DOI： 10.1371/journal.pone.0278613

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Language：Japanese   Publisher：日本病態生理学会  

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Ubiquitination is a representative, reversible biological process of the post-translational modification of various proteins with multiple catalytic reaction sequences, including ubiquitin itself, in addition to E1 ubiquitin activating enzymes, E2 ubiquitin conjugating enzymes, E3 ubiquitin ligase, deubiquitinating enzymes, and proteasome degradation. The ubiquitin-proteasome system is known to play a pivotal role in various molecular life phenomena, including the cell cycle, protein quality, and cell surface expressions of ion-transporters. As such, the failure of this system can lead to cancer, neurodegenerative diseases, cardiovascular diseases, and hypertension. This review article discusses Nedd4-2/NEDD4L, an E3-ubiquitin ligase involved in salt-sensitive hypertension, drawing from detailed genetic dissection analysis and the development of genetically engineered mice model. Based on our analyses, targeting therapeutic regulations of ubiquitination in the fields of cardio-vascular medicine might be a promising strategy in future. Although the clinical applications of this strategy are limited, compared to those of kinase systems, many compounds with a high pharmacological activity were identified at the basic research level. Therefore, future development could be expected.

File： ijms-21-03871.pdf

DOI： 10.3390/ijms21113871

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OBJECTIVE: Excessive prostaglandin E2 production is a hallmark of abdominal aortic aneurysm (AAA). Enhanced expression of prostaglandin E2 receptor EP4 in vascular smooth muscle cells (VSMCs) has been demonstrated in human AAAs. Although moderate expression of EP4 contributes to vascular homeostasis, the roles of excessive EP4 in vascular pathology remain uncertain. We aimed to investigate whether EP4 overexpression in VSMCs exacerbates AAAs. Approach and Results: We constructed mice with EP4 overexpressed selectively in VSMCs under an SM22α promoter (EP4-Tg). Most EP4-Tg mice died within 2 weeks of Ang II (angiotensin II) infusion due to AAA, while nontransgenic mice given Ang II displayed no overt phenotype. EP4-Tg developed much larger AAAs than nontransgenic mice after periaortic CaCl2 application. In contrast, EP4fl/+;SM22-Cre;ApoE-/- and EP4fl/+;SM22-Cre mice, which are EP4 heterozygous knockout in VSMCs, rarely exhibited AAA after Ang II or CaCl2 treatment, respectively. In Ang II-infused EP4-Tg aorta, Ly6Chi inflammatory monocyte/macrophage infiltration and MMP-9 (matrix metalloprotease-9) activation were enhanced. An unbiased analysis revealed that EP4 stimulation positively regulated the genes binding cytokine receptors in VSMCs, in which IL (interleukin)-6 was the most strongly upregulated. In VSMCs of EP4-Tg and human AAAs, EP4 stimulation caused marked IL-6 production via TAK1 (transforming growth factor-β-activated kinase 1), NF-κB (nuclear factor-kappa B), JNK (c-Jun N-terminal kinase), and p38. Inhibition of IL-6 prevented Ang II-induced AAA formation in EP4-Tg. In addition, EP4 stimulation decreased elastin/collagen cross-linking protein LOX (lysyl oxidase) in both human and mouse VSMCs. CONCLUSIONS: Dysregulated EP4 overexpression in VSMCs promotes inflammatory monocyte/macrophage infiltration and attenuates elastin/collagen fiber formation, leading to AAA exacerbation.

File： atv-40-1559.pdf

DOI： 10.1161/ATVBAHA.120.314297

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File： 83_CJ-18-0743.pdf

DOI： 10.1253/circj.CJ-18-0743.

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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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We previously identified a novel nanomagnetic particle, N,N'-bis(salicylidene)ethylenediamine iron [Fe(Salen)]. Fe(Salen) not only shows antitumor effects but also magnetic properties. We found that Fe(Salen) can be used for magnet-guided drug delivery and visualization of accumulated drug by magnetic resonance imaging (MRI) because of its magnetism. In addition, Fe(Salen) can generate heat by itself when exposed to an alternating current magnetic field (AMF), resulting in a hyperthermia effect. Herein, we partly elucidated the antitumor mechanism of Fe(Salen) and carried out an i.v. repeated dose toxicity study to decide the therapeutic amount. Furthermore, we evaluated the antitumor effect of selective intra-arterial injection or i.v. injection of Fe(Salen) by catheter and the hyperthermia effect of Fe(Salen) when exposed to AMF in vivo. We used a rabbit model grafted with VX2 cells (rabbit squamous cell carcinoma) on the right leg. Intra-arterial injection of Fe(Salen) showed a greater antitumor effect than did i.v. injection. The combination of Fe(Salen) intra-arterial injection and AMF exposure showed a greater antitumor effect than did either Fe(Salen) or methotrexate (MTX) without AMF exposure, suggesting that AMF exposure greatly enhanced the antitumor effect of Fe(Salen) by arterial injection by catheter. This is the first report that the effectiveness of Fe(Salen) was evaluated in the point of administration route; that is, selective intra-arterial injection by catheter. Taken together, these results indicate a new administration route; that is, selective arterial injection of Fe(Salen) by catheter, and the development of a new strategy of simultaneous hyperthermia-chemotherapy in the future.

File： Umemura_et_al-2018-Cancer_Science.pdf

DOI： 10.1111/cas.13851

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Nature Publishing Group  

Transforming growth factor-β1 (TGF-β1) induces phenotypic changes in fibroblasts to become myofibroblasts with increased production of extracellular matrix (ECM) components and cytokines. It is also known that excessive activation of myofibroblasts accelerates cardiac fibrosis, remodeling, and thus cardiac dysfunction. However, no effective therapy has been established to prevent this process although recent clinical studies have demonstrated the effectiveness of hyperthermia in cardiac dysfunction. The aim of this study was to examine the molecular mechanism of hyperthermia on TGF-β1-mediated phenotypic changes in cardiac fibroblasts. TGF-β1 increased the expression of IL-6, α-smooth muscle actin (α-SMA), and collagen in human cardiac fibroblasts (HCFs). Hyperthermia (42 °C) significantly prevented these changes, i.e., increases in IL-6, α-SMA, and collagen, as induced by TGF-β1 in a time-dependent manner. Immunoblotting showed that hyperthermia decreased Akt/S6K signaling, but did not affect Smad2 and Smad3 signaling. Pharmacological inhibition of Akt signaling mimicked these effects of hyperthermia. Furthermore, hyperthermia treatment prevented cardiac fibrosis in Ang II infusion mice model. Putting together, our findings suggest that hyperthermia directly inhibits TGF-β-mediated activation of HCFs via suppressing Akt/S6K signaling.

File： Acute Hyperthermia Inhibits TGFβ1-induced.pdf

DOI： 10.1038/s41598-018-24749-6

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File： Akimoto_et_al-2018-Cancer_Science.pdf

DOI： 10.1111/cas.13781.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

File： PHY2-6-e13878.pdf

DOI： 10.14814/phy2.13878

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： Suita2018_Article_VidarabineAnAnti-herpesvirusAg.pdf

DOI： 10.1007/s00424-018-2121-4

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： Tanaka_et_al-2018-Physiological_Reports.pdf

DOI： 10.14814/phy2.13687

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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.

File： journal.pone.0190871.pdf

DOI： 10.1371/journal.pone.0190871

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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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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： Treatment of oral cancer using magnetized paclitaxel.pdf

DOI： 10.18632/oncotarget.24570

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： The iron chelating agent, deferoxamine detoxifies Fe(Salen)-induced cytotoxicity.pdf

DOI： 10.1016/j.jphs.2017.07.002

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： Oda et al. TRPC melanoam article.pdf

DOI： 10.1007/s12576-016-0480-1

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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 β-adrenergic receptor/Gs/adenylyl cyclase, a membrane-bound enzyme that catalyzes the conversion of ATP to cAMP, thereby stimulating protein kinase A (PKA) 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 Epac1 in the heart, however, the magnitude of such dysfunction was significantly smaller. Epac1 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 Epac1 or PKCα was silenced with siRNA. Activation of the cAMP/Epac/PKCα pathway protected the heart against cytokine-induced cardiac dysfunction, suggesting a new role of catecholamine signaling in compensating for cardiac dysfunction in heart failure. Epac1 and its downstream pathways may be novel targets for treating cardiac dysfunction in endotoxemia.

File： 1-s2.0-S0022282817301153-main.pdf

DOI： 10.1016/j.yjmcc.2017.05.014.

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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.

File： Magnetic metal-complex-conducting copolymer.pdf

DOI： 10.1038/am.2017.29

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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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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： Hyperthermia and chemotherapy using Fe(Salen) nanoparticles might impact glioblastoma treatment.pdf

DOI： 10.1038/srep42783

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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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Language：English   Publisher：(一社)日本癌学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： Simultaneous hyperthermiachemotherapy.pdf

DOI： 10.1038/srep24629

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PUBLIC LIBRARY SCIENCE  

Background
Atrial fibrillation (AF) is the most common arrhythmias among old people. It causes serious long-term health problems affecting the quality of life. It has been suggested that the autonomic nervous system is involved in the onset and maintenance of AF in human. However, investigation of its pathogenesis and potential treatment has been hampered by the lack of suitable AF models in experimental animals.
Objectives
Our aim was to establish a long-lasting AF model in mice. We also investigated the role of adrenergic receptor (AR) subtypes, which may be involved in the onset and duration of AF.
Methods and Results
Trans-esophageal atrial burst pacing in mice could induce AF, as previously shown, but with only a short duration (29.0 +/- 8.1 sec). We found that adrenergic activation by intraperitoneal norepinephrine (NE) injection strikingly increased the AF duration. It increased the duration to more than 10 minutes, i.e., by more than 20-fold (656.2 +/- 104.8 sec; P<0.001). In this model, a prior injection of a specific beta 1-AR blocker metoprolol and an alpha 1-AR blocker prazosin both significantly attenuated NE-induced elongation of AF. To further explore the mechanisms underlying these receptors' effects on AF, we assessed the SR Ca2+ leak, a major trigger of AF, and consequent spontaneous SR Ca2+ release (SCR) in atrial myocytes. Consistent with the results of our in-vivo experiments, both metoprolol and prazosin significantly inhibited the NE-induced SR Ca2+ leak and SCR. These findings suggest that both beta 1-AR and alpha 1-AR may play important roles in the development of AF.
Conclusions
We have established a long-lasting AF model in mice induced by adrenergic activation, which will be valuable in future AF study using experimental animals, such as transgenic mice. We also revealed the important role of beta 1- and alpha 1-AR-mediated signaling in the development of AF through in-vivo and in-vitro experiments.

DOI： 10.1371/journal.pone.0133664

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Myocardial beta-adrenergic receptor (beta-AR) beta(1)- and beta(2)-subtypes are highly homologous, but play opposite roles in cardiac apoptosis and heart failure, as do cardiac adenylyl cyclase (AC) subtypes 5 (AC5) and 6 (AC6): beta(1)-AR and AC5 promote cardiac remodeling, while beta(2)-AR and AC6 activate cell survival pathways. However, the mechanisms involved remain poorly understood. We hypothesized that AC5 is coupled preferentially to beta(1)-AR rather than beta(2)-AR, and we examined this idea by means of pharmacological and genetic approaches. We found that selective inhibition of AC5 with 2'5'-dideoxyadenosine significantly suppressed CAMP accumulation and cardiac apoptosis induced by selective beta(1)-AR stimulation, but had no effect on cAMP accumulation and cardiac apoptosis in response to selective beta(2)-AR stimulation. The results of selective stimulation of beta(1)-AR and beta(2)-AR in neonatal cardiac myocytes prepared from wild-type and AC5-knockout mice were also consistent with the idea that beta(1)-AR selectively couples with AC5. We believe these results are helpful for understanding the mechanisms underlying the different roles of AR subtypes in healthy and diseased hearts. (C) 2015 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2015.01.149

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

At birth, dynamic changes occur in serum components and haemodynamics, such as closure of the ductus arteriosus (DA). A previous study demonstrated that, in full-term human neonates, serum osmolality decreased transiently after birth, but recovered over the next few days. However, the significance of this transient decrease in osmolality has never been addressed. The objective of the present study was to examine the role of changes in serum osmolality after birth in DA closure.
We found that rats exhibited a similar transient hypoosmolality after birth. Hypotonic stimulation induced constriction of DA rings and increased Ca2+ transient in DA smooth muscle cells, but not in the aorta. The hypoosmotic sensor transient receptor potential melastatin 3 (TRPM3) was highly expressed in the rat DA, and TRPM3 silencing abolished the Ca2+ response to hypoosmolality. Pregnenolone sulfate stimulation of TRPM3 induced rat DA constriction ex vivo and in vivo. Furthermore, hypertonic fluid injection impaired rat DA closure. In humans, neonatal serum hypoosmolality was observed in relatively mature preterm infants (a parts per thousand yen28 weeks). In extremely preterm infants (< 28 weeks), however, this hypoosmolality was absent. Instead, a rapid increase in osmolality occurred thereafter. Such an increase was greater, in particular, among patent DA (PDA) patients.
A transient decrease in serum osmolality may promote DA closure during the first few days of life. Adjusting serum osmolality to proper levels might help to prevent the onset of PDA, improving the therapeutic outcome in extremely preterm infants.

DOI： 10.1093/cvr/cvu199

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DOI： 10.1097/HJH.0000000000000293

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Renin belongs to a family of aspartyl proteases and is the rate-limiting enzyme in the synthesis of the potent vasoactive peptide angiotensin II. Processing of renal renin has been extensively investigated in juxtaglomerular granular cells, in which prorenin and active renin are present in secretory condensed granules. Previous studies demonstrated alternative renin transcription in rat adrenal glands. Different studies reported novel intracellular forms of renin deduced from novel 5 variants derived from renin mRNA in both mice and humans. Comprehensive detailed studies in genetically engineered mice showed that both a secreted and an intracellular form of renin plays divergent mechanism regulating fluid intake and metabolism by the brain renin-angiotensin system; however, the presence, regulation, and functions of these renin isoforms in kidney and adrenal gland are not fully understood in mice. To investigate the characteristics of renin isoforms in mice, we performed a systematic inventory of renin transcripts of mice with and without a duplication of the renin gene alternatively from previous studies. We discovered a novel isoform of renin of the Ren2 gene, which conserved functionally important residues of the prosegment and incomplete isoforms of the Ren1C/D gene lacking a pre-pro segment. In situ hybridization assays revealed alternative renin isoforms expressed along cortical tubules. Newly generated transgenic mice with systemic overexpression of alternative renin transcript showed enhanced local angiotensin II generation without elevation of plasma renin activity and systemic insulin resistance in vivo, providing new pathophysiological insights into insulin resistance exaggerated by bona fide renin isoform.

DOI： 10.1161/HYPERTENSIONAHA.114.03394

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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.

File： Epac1-dependent phospholamban.pdf

DOI： 10.1172/JCI64784

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER JAPAN KK  

Hyperthermia is a promising anti-cancer treatment in which the tissue temperature is increased to 42-45 A degrees C, and which is often used in combination with chemotherapy or radiation therapy. Our aim in the present work was to examine the feasibility of combination therapy for oral cancer with cisplatin and hyperthermia generated with ferucarbotran (Resovist(A (R)); superparamagnetic iron oxide) in an alternating magnetic field (AMF). First, we established that administration of ferucarbotran at the approved dosage for magnetic resonance imaging provides an iron concentration sufficient to increase the temperature to 42.5 A degrees C upon exposure to AMF. Then, we examined the effect of cisplatin combined with ferucarbotran/AMF-induced hyperthermia on cultured human oral cancer cells (HSC-3 and OSC-19). Cisplatin alone induced apoptosis of cancer cells in a dose-dependent manner, as is well known. However, the combination of cisplatin with ferucarbotran/AMF was significantly more effective than cisplatin alone. This result suggests that it might be possible to reduce the clinically effective dosage of cisplatin by administering it in combination with ferucarbotran/AMF-induced hyperthermia, thereby potentially reducing the incidence of serious cisplatin-related side effects. Further work seems justified to evaluate simultaneous thermo-chemotherapy as a new approach to anticancer therapy.

DOI： 10.1007/s12576-014-0309-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：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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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：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.

File： The Prostanoid EP4 Receptor and Its Signaling Pathway.pdf

DOI： 10.1124/pr.112.007195

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Cyclic AMP is an ubiquitous molecule that serves as an important second messenger for multiple signaling pathways. At least nine membrane-bound mammalian isoforms of adenylyl cyclase have been identified, and each isoform has a distinct pattern of tissue distribution as well as interaction with regulatory proteins within local cytosolic environment. Adenylyl cyclase is coupled to G-protein receptors and serves to convert ATP to cAMP. Although many of the upstream G-protein receptors and cAMP regulators such as phosphodiesterase have been utilized as targets of pharmacotherapy, the attempt of pharmacologic regulation of adenylyl cyclase itself has not been successful. Recent studies have characterized the distinct physiologic effect of each adenylyl cyclase isoform within different organ systems, suggesting the potential therapeutic utility of isoform-specific regulators of adenylyl cyclase. In the current review, we aim to discuss the effects of genetic regulation for each adenylyl cyclase isoform as well as the development of isoformspecific adenylyl cyclase regulators including their therapeutic potential. © 2012 Bentham Science Publishers.

File： Recent Advance in Isoform-Specific Regulation of Adenylyl Cyclase.pdf

DOI： 10.2174/157340812800793282

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Iwatsubo K, Bravo C, Uechi M, Baljinnyam E, Nakamura T, Umemura M, Lai L, Gao S, Yan L, Zhao X, Park M, Qiu H, Okumura S, Iwatsubo M, Vatner DE, Vatner SF, Ishikawa Y. Prevention of heart failure in mice by an antiviral agent that inhibits type 5 cardiac adenylyl cyclase. Am J Physiol Heart Circ Physiol 302: H2622-H2628, 2012. First published April 13, 2012; doi:10.1152/ajpheart.00190.2012.-Despite numerous discoveries from genetically engineered mice, relatively few have been translated to the bedside, mainly because it is difficult to translate from genes to drugs. This investigation examines an antiviral drug, which also has an action to selectively inhibit type 5 adenylyl cyclase (AC5), a pharmaceutical correlate of the AC5 knockout (KO) model, which exhibits longevity and stress resistance. Our objective was to examine the extent to which pretreatment with this drug, adenine 9-beta-D-arabinofuranoside (Ara-A), favorably ameliorates the development of heart failure (HF). Ara-A exhibited selective inhibition for AC5 compared with the other major cardiac AC isoform, AC6, i.e., it reduced AC activity significantly in AC5 transgenic (Tg) mice, but not in AC5KO mice and had little effect in either wild-type or AC6Tg mice. Permanent coronary artery occlusion for 3 wk in C57Bl/6 mice increased mortality and induced HF in survivors, as reflected by reduced cardiac function, while increasing cardiac fibrosis. The AC5 inhibitor Ara-A significantly improved all of these end points and also ameliorated chronic isoproterenol-induced cardiomyopathy. As with the AC5KO mice, Ara-A increased mitogen/extracellular signal-regulated kinase (MEK)/extracellular signal-regulated kinase (ERK) phosphorylation. A MEK inhibitor abolished the beneficial effects of the AC5 inhibitor in the HF model, indicating the involvement of the downstream MEK-ERK pathway of AC5. Our data suggest that pharmacological AC5 inhibition may serve as a new therapeutic approach for HF.

File： Prevention of heart failure in mice by an antiviral agent.pdf

DOI： 10.1152/ajpheart.00190.2012

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHURCHILL LIVINGSTONE INC MEDICAL PUBLISHERS  

There are few reports of acute myocardial infarction (AMI) relating to the occlusion of the conus branch, most of which are iatrogenic in nature. So far as we are concerned, this is the first case of spontaneous AMI with isolated conus branch occlusion. Electrocardiogram (ECG) showed mild elevation of ST segment in leads V-1 through V-3. Cardiac makers of myocardial infarction were positive. Right coronary angiography revealed an isolated occlusion of the conus branch. Penetration of the guidewire in the occluded lesion was attempted, and recanalization was successfully achieved. The patient was discharged without any adverse events. (c) 2012 Elsevier Inc. All rights reserved.

File： Acute myocardial infarction with isolated conus branch occlusion.pdf

DOI： 10.1016/j.jelectrocard.2011.11.006

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Background: We report a rare case of acute pulmonary embolism (PE) induced by urinary retention and bladder distention with benign prostatic hyperplasia (BPH). Case report: A 76-year-old male with BPH presented to the hospital with anuria of 24. h duration and abdominal distention. Physical examination revealed tenderness and distention of the lower abdomen and a swollen right leg. Echocardiography after urethral catheterization showed a large free-floating thrombus traversing back and forth through the tricuspid orifice. Computed tomographic angiography demonstrated filling defects at the level of the right inter lobar pulmonary artery and the segmental branches of both pulmonary arteries, indicating acute PE. The patient was treated with heparin and warfarin for three weeks to ensure the resolution of the pulmonary embolus. After the resolution of all symptoms, the patient was discharged without further complication. Conclusion: This case suggested that a distended bladder is a potential risk factor for the development of deep vein thrombosis and PE. © 2011 Japanese College of Cardiology.

File： Acute pulmonary embolism induced by renal.pdf

DOI： 10.1016/j.jccase.2011.10.004

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Epithelial sodium channels (ENaC) are ion transporters in the aldosterone-sensitive distal nephron that play an important role in sodium reabsorption in the terminal nephron. Our study of inbred C57Bl6/J mice given a high-sodium diet showed increased ENaC expression accompanied by tubular renin activation on qRT-PCR of laser-captured tubule specimens and Western blotting of membrane proteins, despite inhibition of aldosterone. Treatment with an angiotensin-converting-enzyme inhibitor (ACEI) or an angiotensin receptor blocker (ARB) effectively lowered blood pressure. In addition to lowering blood pressure, ACEI and ARB inhibition downregulated ENaC and renin expression in renal tubules. These effects would act to suppress sodium reabsorption via ENaC and normalize molecular mechanisms that elevate blood pressure in response to increased salt intake. Copyright (C) 2013 S. Karger AG, Basel

DOI： 10.1159/000348660

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Our previous report suggested the potential role of the exchange protein directly activated by cyclic AMP (Epac) in melanoma metastasis via heparan sulfate (HS)-mediated cell migration. In order to obtain conclusive evidence that Epac1 plays a critical role in modification of HS and melanoma metastasis, we extensively investigated expression and function of Epac1 in human melanoma samples and cell lines. We have found that, in human melanoma tissue microarray, protein expression of Epac1 was higher in metastatic melanoma than in primary melanoma. In addition, expression of Epac1 positively correlated with that of N-sulfated HS, and N-deacetylase/N-sulfotransferase-1 (NDST-1), an enzyme that increases N-sulfation of HS. Further, an Epac agonist increased, but ablation of Epac1 decreased, expressions of NDST-1, N-sulfated HS, and cell migration in various melanoma cell lines. Finally, C8161 cells with stable knockdown of Epac1 showed a decrease in cell migration, and metastasis in mice. These data suggest that Epac1 plays a critical role in melanoma metastasis presumably because of modification of HS.

DOI： 10.1111/j.1755-148X.2011.00863.x

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Background: Recently we reported that activation of Epac1, an exchange protein activated by cAMP, increases melanoma cell migration via Ca (2+) release from the endoplasmic reticulum (ER). G-protein beta gamma subunits (G beta gamma) are known to act as an independent signaling molecule upon activation of G-protein coupled receptor. However, the role of G beta gamma in cell migration and Ca (2+) signaling in melanoma has not been well studied. Here we report that there is crosstalk of Ca (2+) signaling between G beta gamma and Epac in melanoma, which plays a role in regulation of cell migration.
Methods: SK-Mel-2 cells, a human metastatic melanoma cell line, were mainly used in this study. Intracellular Ca (2+) was measured with Fluo-4AM fluorescent dyes. Cell migration was examined using the Boyden chambers.
Results: The effect of G beta gamma on Epac-induced cell migration was first examined. Epac-induced cell migration was inhibited by mSIRK, a G beta gamma -activating peptide, but not its inactive analog, L9A, in SK-Mel-2 cells. Guanosine 5', alpha-beta-methylene triphosphate (Gp(CH2)pp), a constitutively active GTP analogue that activates G beta gamma, also inhibited Epac-induced cell migration. In addition, co-overexpression of beta 1 and gamma 2, which is the major combination of G beta gamma, inhibited Epac1-induced cell migration. By contrast, when the C-terminus of beta adrenergic receptor kinase (beta ARK-CT), an endogenous inhibitor for G beta gamma, was overexpressed, mSIRK's inhibitory effect on Epac-induced cell migration was negated, suggesting the specificity of mSIRK for G beta gamma. We next examined the effect of mSIRK on Epac-induced Ca (2+) response. When cells were pretreated with mSIRK, but not with L9A, 8-(4-Methoxyphenylthio)-2'-O-methyladenosine-3',5'-cyclic monophosphate (8-pMeOPT), an Epac-specific agonist, failed to increase Ca (2+) signal. Co-overexpression of beta 1 and gamma 2 subunits inhibited 8-pMeOPT-induced Ca (2+) elevation. Inhibition of G beta gamma with beta ARK-CT or guanosine 5'-O-(2-thiodiphosphate) (GDP beta S), a GDP analogue that inactivates G beta gamma, restored 8-pMeOPT-induced Ca (2+) elevation even in the presence of mSIRK. These data suggested that G beta gamma inhibits Epac-induced Ca (2+) elevation. Subsequently, the mechanism by which G beta gamma inhibits Epac-induced Ca (2+) elevation was explored. mSIRK activates Ca (2+) influx from the extracellular space. In addition, W-5, an inhibitor of calmodulin, abolished mSIRK's inhibitory effects on Epac-induced Ca (2+) elevation, and cell migration. These data suggest that, the mSIRK-induced Ca (2+) from the extracellular space inhibits the Epac-induced Ca (2+) release from the ER, resulting suppression of cell migration.
Conclusion: We found the cross talk of Ca (2+) signaling between G beta gamma and Epac, which plays a major role in melanoma cell migration.

File： Gbg subunits inhibit Epac-induced melanoma.pdf

DOI： 10.1186/1471-2407-11-256

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Epithelial sodium channels (ENaC) located along the aldosterone-sensitive distal nephron (ASDN) play a pivotal role in the homeostasis of sodium balance. Among various modulating proteins, E3 ubiquitin ligase, Nedd4L, binds the PY motif of ENaC COOH terminals and catalyzes ubiquitination of the NH(2) terminal of the protein for subsequent degradation. One of the isoforms of human Nedd4L with evolutionarily new C2 domain was reported to play a significant role for degradating cell surface ENaC with interfering with wild isoforms by us previously. We focused the current analyses on isolating the binding molecules with C2 domain using yeast two-hybrid screening to elucidate further molecular interactions between ENaC and Nedd4L. We found NPC2, also known as HE-1, bind C2 domain of human Nedd4L and express along ASDN colocalized with Nedd4L. Additionally, in experiments using a model of salt-sensitive hypertension in Dahl rats, we provided evidence suggesting that transcriptional regulation and activation of NPC2 protein depends on sodium intake. NPC2 might regulate sodium reabsorption in the terminal nephron by interacting with ENaC-Nedd4L system. (C) 2009 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2009.07.158

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Net sodium balances in humans are maintained through various ion transporters expressed along the entire nephron. Among these ion transporters, epithelial sodium channels (ENaC) located along the aldosterone-sensitive distal nephron (ASDN) play a pivotal role in the homeostasis of sodium balance. This is supported by analyses of inherited hypertensive disorders, showing that genes encoding ENaC and other modulatory proteins cause hereditary hypertension, such as Liddle syndrome. Among various modulating proteins, E3 ubiquitin ligase, Nedd4L, binds the PY motif of ENaC COOH terminals and catalyzes ubiquitination of the NH2 terminus of the protein for subsequent degradation. Both evolutionarily conserved and evolutionarily new C2 domains of human Nedd4L, a cryptic splice variant resulting in a disrupted isoform product formed by a frame-shift mutation, were reported previously. We focused on one of the isoforms, isoform I, generated by SNP (rs4149601), and studied its expression and interactions with other isoforms by molecular biological, immunohistochemical, and electrophysiological methods. We found that isoform I may interact with other human isoforms in a dominant-negative fashion. Such interactions might abnormally increase sodium reabsorption. Taken together, our analyses suggest that the human Nedd4L gene, especially the evolutionarily new isoform I, is a candidate gene for hypertension.

DOI： 10.1161/HYPERTENSIONAHA.107.102061

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL PUBLISHING  

The ubiquitin ligase, NEDD4L, participates in plasma volume and blood pressure regulation by controlling cell surface expression of kidney epithelial sodium channel (ENaC). Impairment of ENaC internalization with disrupting Nedd4L binding PY motif in the C-terminal of the protein showed rare Mendelian human hypertension disorder, Liddle syndrome. Therefore, possible involvements of ENaC-Nedd4L system abnormalities were suggested in development of human hypertension. Previously, we discovered a common variant, named v13(G/A), that affects the formation of an evolutionally new C2-encoding isoform of the Nedd4L gene in humans. The aim of this study was to test a hypothesis whether this variant is involved in essential hypertension; we performed the association study in a sample of the Japanese population. We found a gender-specific genotypic and allelic association with statistical significance achieved only in males. Our data suggest that this Genetic variation may contribute to essential hypertension in Japanese male patients through the mechanism of disrupting the C2 encoding isoform in vivo. Furthermore, molecular and functional studies will be required to elucidate the mechanism by which genetic variation in NEDD4L contributes to the development of essential hypertension.

DOI： 10.1111/j.1447-0594.2007.00382.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Activation of angiotensin II (Ang II) type I receptor (AT1R) signaling is reported to play an important role in cardiac hypertrophy. We previously cloned a novel molecule interacting with the AT1R, which we named ATRAP (for Ang II type I receptor-associated protein). Here, we report that overexpression of ATRAP significantly decreases the number of AT1R on the surface of cardiomyocytes, and also decreases the degree of p38 mitogen-activated protein kinase phosphorylation, the activity of the c-fos promoter and protein synthesis upon Ang II treatment. These results indicate that ATRAP significantly promotes downregulation of the AT1R and further attenuates certain Ang II-mediated hypertrophic responses in cardiomyocytes. (c) 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

DOI： 10.1016/j.febslet.2005.01.068

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Cholesterol crystal embolism (CCE) is caused by the shedding of cholesterol crystals into the bloodstream, and it has been recently recognized as a serious complication after vascular procedures. Our case of CCE, which was diagnosed by skin and renal biopsies, occurred in a patient with hypertension and diabetes mellitus, 3 months after coronary angiography, with the development of renal failure and blue toes. After low-density lipoprotein apheresis (LDL-A), the skin lesions, including livedo reticularis and pain from the acrocyanotic toes, dramatically improved, with partial recovery of renal function. Following the administration of low-dose corticosteroid and candesartan - an angiotensin II type 1 receptor antagonist (ARB) - the eosinophilia disappeared and renal function improved gradually with a decrease in urinary protein excretion. Therefore, a combination therapy of LDL-A, low-dose corticosteroid, and an ARB is a possible treatment for CCE, although the possibility of spontaneous recovery of renal function cannot be eliminated for this patient.

DOI： 10.1007/s101570300010

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：The Japanese Pharmacological Society  

Doxorubicin (DOX)-induced cardiomyopathy has a poor prognosis. No early detection or effective treatment methods are available in clinical. The mechanisms of cardiotoxicity were considered as oxidative stress and apoptosis in cardiomyocytes. However, the effect of DOX on cardiac fibroblasts remains to be developed. We investigated the direct effect of DOX on the function of human cardiac fibroblasts (HCFs) independently of cell death pathway. Animal study showed that lower dose of DOX (4 mg/kg/week for 3 weeks, <i>i.p.</i>) than a toxic cumulate dose, induced perivascular fibrosis without cell death in hear of mice. DOX increased the protein expression of α-SMA (a marker of trans-differentiation) in HCFs culture cells, indicating that DOX promoted the trans-differentiation of HCFs into myofibroblast. DOX also increased the mRNA and protein expression of matrix metalloproteinase (MMP)-1 in less than 0.1 μM which did not induce cell apoptosis of HCFs cells via PI3K/Akt pathway in HCFs. DOX increased Interleukin-6 (IL-6) via transforming growth factor (TGF)-β/Smad pathway. In addition, DOX induced the mitochondrial damage and increased the expression of Interleukin-1 (IL-1) via stress-activated protein kinases (SAPK)/ c-Jun NH-2termial kinase (JNK). A peroxisome proliferator-activated receptor gamma (PPARγ) agonist, pioglitazone hydrochloride attenuated the expression of fibrotic marker such as α-SMA and galectin-3 and collagen1 via SAPK/JNK signaling. Pioglitazone also suppressed DOX-induced early fibrotic response in vivo. In conclusion, these findings suggested that low dose DOX induced reactive fibrotic change of cardiac fibroblasts via cell death-independent pathway. There may be potentially new mechanisms of DOX induced cardiotoxicity in clinical usage.

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DOI： 10.1254/fpj.20101

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Other Link： http://id.ndl.go.jp/bib/031499535

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)   Publisher：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)

File： 市販医薬品の薬効成分を磁性化する画期的技術の開発.pdf

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Authorship：Corresponding author   Language：Japanese   Publisher：(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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J-GLOBAL

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J-GLOBAL

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Language：Japanese   Publisher：(一社)日本心臓病学会  

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Language：English   Publisher：(一社)日本癌学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：JAPANESE PHARMACOLOGICAL SOC  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：JAPANESE PHARMACOLOGICAL SOC  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER SCI LTD  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2015-4398

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2015-4548

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2015-4371

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Language：Japanese   Publisher：日本病態生理学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2014-4576

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2014-5399

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Language：Japanese   Publisher：(一社)日本頭頸部癌学会  

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Language：Japanese   Publisher：(一社)日本ハイパーサーミア学会  

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Language：Japanese   Publisher：(公社)日本薬学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2013-5567

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2013-5568

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：SPRINGER JAPAN KK  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：SPRINGER JAPAN KK  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：SPRINGER JAPAN KK  

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Language：Japanese   Publisher：(NPO)日本高血圧学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2012-1864

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Language：Japanese   Publisher：(NPO)日本高血圧学会  

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DOI： 10.1158/1538-7445.AM2011-4553

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2011-3664

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：AMER ASSOC CANCER RESEARCH  

DOI： 10.1158/1538-7445.AM2011-5259

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：English   Publisher：Japanese Circulation Society  

CiNii Books

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Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Books

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Language：Japanese   Publisher：ライフサイエンス出版(株)  

PCPS装着後離脱しえた循環虚脱を伴う重症急性肺血栓塞栓症(collapse type APE)11例(男性2例、女性9例、平均62歳)を対象として、PCPS装着中の呼吸循環動態について検討した。循環虚脱状態出現からPCPS開始までに要した時間は平均25分で、自己心拍は10例でPCPS開始直後に、1例で15分後に再開した。全例内科的治療のみで、外科手術を行わずにPCPSから離脱し、PCPS装着時間は平均15時間36分であった。End-tidal CO2(EtCO2)が20 Torr以上に改善するまでに要した時間は平均11.6±10時間で、特に11例中5例では、PCPS開始後6時間以内に病態改善が認められた。Collapse type APEではPCPS使用下に内科的治療のみで早期の呼吸循環動態の改善が期待できる可能性があり、その治療方針決定の指標としてEtCO2は有用であると考えられた。

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Language：Japanese   Publisher：ライフサイエンス出版(株)  

一時的下大静脈フィルター(IVCF)を使用した急性肺血栓塞栓症(APE)79例(男性28例、女性51例、平均61歳)を対象として、その有効性と合併症について検討した。IVCFの平均留置期間は12日で、結果としてIVCF留置中のAPE再発はなく、IVCF抜去後に2例で再発を認めたが、いずれもヘパリン起因性血小板減少症合併例であった。主な合併症として、感染を9例、フィルターの変位を7例、フィルターへの血栓付着を29例に認めた。フィルターへの血栓付着を認めた29例のうち、血栓が少量でそのまま抜去できたのは22例で、6例では血栓溶解療法追加後に抜去、1例では下大静脈の閉塞をきたし、外科的な下大静脈結紮術を要した。またIVCF留置期間と合併症との関係を検討した結果、8日以上の長期留置例で、合併症頻度が著明に増加していた。IVCFはAPE急性期の再発予防に有効と考えられるが合併症の危険性もあり、慎重な検討、管理を行い、短期間での使用に留めるべきである。

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Other Link： https://search-tp.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2007&ichushi_jid=J01759&link_issn=&doc_id=20070710240023&doc_link_id=%2Fai6serrc%2F2007%2F002806%2F026%2F1036-1037%26dl%3D0&url=https%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Fai6serrc%2F2007%2F002806%2F026%2F1036-1037%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

Language：Japanese   Publisher：日本静脈学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：Japanese   Publisher：(一社)日本心臓病学会  

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Other Link： http://search.jamas.or.jp/link/ui/2006192097

Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Books

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Language：English   Publisher：Japanese Circulation Society  

CiNii Books

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Language：English   Publisher：Japanese Circulation Society  

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Language：Japanese   Publisher：(株)先端医学社  

レニン・アンジオテンシン(RA)系は循環血圧調節や水・電解質代謝に重要な役割を担っているとともに心血管病の発症・進展に深く関与している.われわれは以前からRA系遺伝子発現調節機構およびアンジオテンシンII(A II)受容体情報伝達系の病態生理学的意義に関する研究をおこなってきた.今回,循環血中RA系の律速段階酵素であるレニンの遺伝子発現に関与する新規転写調節因子,および循環血中および組織RA系の作用発現に重要なAT1受容体に直接結合する制御因子の単離同定をおこなった.今後,これら新規RA系活性制御因子の機能解析をおこなうことにより,RA系遺伝子発現調節機構およびA II受容体情報伝達系の病態生理学的意義についての分子レベルでの理解が一層深まると期待される(著者抄録)

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Language：Japanese   Publisher：(株)先端医学社  

アンジオテンシノーゲン(AGT)遺伝子は,分子遺伝学的研究から本態性高血圧症の有力な候補遺伝子である可能性が示唆されている.生体におけるレニン・アンジオテンシン(RA)系の概念は,全身性(systemic)RA系から1990年代には,局所性(local)RA系へとparadigm shiftし,その概念は,今日循環器疾患や腎疾患におけるARB,ACE阻害薬の薬効・薬理作用の理論的根拠を提供している.一方,分子遺伝学的成果をもとにしたAGT遺伝子による,本態性高血圧症の成因を考えた場合,この2つの概念では十分に説明しうる仮説を提示することはできなかった.われわれがこれまでに提供してきた尿細管RA系の概念は,このジレンマを解決しうる有力な概念であると考えられる.本研究では,近位尿細管でのAGT遺伝子の発現の制御に関して検討した(著者抄録)

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Language：Japanese   Publisher：南山堂  

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Other Link： http://search.jamas.or.jp/link/ui/2006050115

Language：English   Publisher：Japanese Circulation Society  

CiNii Books

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Language：Japanese   Publisher：(株)先端医学社  

ヒトアンジオテンシノーゲン(AGT)遺伝子は,本態性高血圧症の有力な候補遺伝子のひとつである.その病態生理学的メカニズムとして,われわれは,腎臓の近位尿細管で産生され尿細管液中に分泌されるアンジオテンシノーゲンに注目し,遠位尿細管と集合管とのあいだの接合部尿細管(CNT:conneting tubule)で産生・分泌されるレニンとともに,尿細管レニン・アンジオテンシン系(tubular RAS)を構成し,尿細管でのナトリウム再吸収を制御することで,本症の発症に関与するメカニズムを提唱してきた.今回われわれは,この研究をさらに発展させ,CNTにおけるレニンとカリクレインの機能的・解剖学的共局在の意義を検討した(著者抄録)

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Language：Japanese   Publisher：(株)南山堂  

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Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Books

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Language：English   Publisher：Japanese Circulation Society  

CiNii Books

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Language：English   Publisher：Japanese Circulation Society  

CiNii Books

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Language：Japanese   Publisher：日本ベーリンガーインゲルハイム(株)  

68歳男.胸部圧迫感の精査として心臓カテーテル検査を行ったところ3ヵ月後に下肢潰瘍が出現し,腎機能低下を認めた.精査により糖尿病性腎症に合併したコレステロール結晶塞栓症と診断した.利尿薬とプロスタグランジンI2の投与を行ったが腎機能と炎症所見がさらに悪化した.LDL吸着療法を行ったところ皮膚症状は劇的に改善した.その後も腎機能障害やCRP高値が続くためプレドニゾロン20mg/日の投与を行い,改善が得られた

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Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Books

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Language：Japanese   Publisher：日本ベーリンガーインゲルハイム(株)  

73歳男.心不全で治療中に感冒様症状と手足の浮腫が出現した.TP 5.1g/dl,Alb 2.4g/dl,総コレステロール415mg/dl,TG 257mg/dlと著明な低蛋白血症,低アルブミン血症,高脂血症を認め,BUN 68mg/dl,CRNN 3.8mg/dl,Ccr 9.7ml/min,FENa 0.56%と腎機能低下が認められた.内分泌学的検査,画像検査,心電図所見と併せて急性腎不全を合併したネフローゼ症候群と診断し,輸液,利尿薬,PGE1投与に加え,血液透析を5回施行した.又,腎内血行動態の改善を目的としてアンジオテンシンII受容体拮抗薬バルサルタンの少量投与を開始した.経過中,ARA分類基準を満たしていることより,全身性エリテマトーデスの可能性が高いと考えた.しかし腎生検では,光顕でごく軽度の巣状分節状のメサンギウム増殖性病変が認められたが,電顕上electron dense depositsは殆ど認めず,上皮細胞脚突起の広範な癒合を認め,ループス腎炎或いは微小変化群を疑った.尿蛋白,CRNNが改善した時点よりステロイドパルス療法を行い,症状は軽快して退院した

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Language：Japanese   Publisher：(株)東京医学社  

53歳女.主訴は発熱,腹痛,CAPD排液混濁.CAPD排液では多核球優位の細胞増加を認め,末梢血にて貧血と白血球の左方移動を認めた.生化学所見では低蛋白,低アルブミン血症,電解質異常を認め,免疫学的検査では,CRPの高度上昇とβ-D-グルカン高値を認めた.心電図検査では洞性頻脈,左房負荷,及び軽度のQTc延長がみられ,胸部X線検査では,心拡大と左優位の胸水,及び軽度の肺鬱血がみられた.腹部X線検査では,腸管ガス減少と中心部よりやや左側腹部に腸管ガスの圧排像がみられ腫瘤や膿瘍の存在が疑われた.炎症所見が増悪した為,開腹洗浄ドレナージ術を施行した.血液透析後にFLCZ投与を行い腹腔内洗浄処置を行ったところ,突然心肺停止状態となり心肺蘇生術を施行され,その後意識は回復し,特に後遺障害は認められなかった

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Event date： 2023.4

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