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Kiryu, Japan

Gunma University , abbreviated to Gundai , is a national university in Japan. The main campus is located in Aramaki-machi, Maebashi City, Gunma Prefecture. Wikipedia.

Koitabashi N.,Gunma University | Kass D.A.,Johns Hopkins Medical Institutions
Nature Reviews Cardiology | Year: 2012

Heart failure (HF) involves changes in cardiac structure, myocardial composition, myocyte deformation, and multiple biochemical and molecular alterations that impact heart function and reserve capacity. Collectively, these changes have been referred to as 'cardiac remodeling'. Understanding the components of this process with the goal of stopping or reversing its progression has become a major objective. This concept is often termed 'reverse remodeling', and is successfully achieved by inhibitors of the renin-angiotensin-aldosterone system, β-blockers, and device therapies such as cardiac resynchronization or ventricular assist devices. Not every method of reverse remodeling has long-lasting clinical efficacy. However, thus far, every successful clinical treatment with long-term benefits on the morbidity and mortality of patients with HF reverses remodeling. Reverse remodeling is defined by lower chamber volumes (particularly end-systolic volume) and is often accompanied by improved β-adrenergic and heart-rate responsiveness. At the cellular level, reverse remodeling impacts on myocyte size, function, excitation-contraction coupling, bioenergetics, and a host of molecular pathways that regulate contraction, cell survival, mitochondrial function, oxidative stress, and other features. Here, we review the current evidence for reverse remodeling by existing therapies, and discuss novel approaches that are rapidly moving from preclinical to clinical trials. © 2012 Macmillan Publishers Limited. All rights reserved.

Endothelium is a crucial blood-tissue interface controlling energy supply according to organ needs. We investigated whether peroxisome proliferator-activated receptor-γ (PPARγ) induces expression of fatty acid-binding protein 4 (FABP4) and fatty acid translocase (FAT)/CD36 in capillary endothelial cells (ECs) to promote FA transport into the heart. Expression of FABP4 and CD36 was induced by the PPARγ agonist pioglitazone in human cardiac microvessel ECs (HCMECs), but not in human umbilical vein ECs. Real-time PCR and immunohistochemistry of the heart tissue of control (Pparg(fl/null)) mice showed an increase in expression of FABP4 and CD36 in capillary ECs by either pioglitazone treatment or 48 hours of fasting, and these effects were not found in mice deficient in endothelial PPARγ (Pparg({up triangle, open})(EC)(/null)). Luciferase reporter constructs of the Fabp4 and CD36 promoters were markedly activated by pioglitazone in HCMECs through canonical PPAR-responsive elements. Activation of PPARγ facilitated FA uptake by HCMECs, which was partially inhibited by knockdown of either FABP4 or CD36. Uptake of an FA analogue, (125)I-BMIPP, was significantly reduced in heart, red skeletal muscle, and adipose tissue in Pparg({up triangle, open})(EC)(/null) mice as compared with Pparg(fl/null) mice after olive oil loading, whereas those values were comparable between Pparg(fl/null) and Pparg({up triangle, open})(EC)(/null) null mice on standard chow and a high-fat diet. Furthermore, Pparg({up triangle, open})(EC)(/null) mice displayed slower triglyceride clearance after olive oil loading. These findings identified a novel role for capillary endothelial PPARγ as a regulator of FA handing in FA-metabolizing organs including the heart in the postprandial state after long-term fasting.

Mizuno-Yamasaki E.,Gunma University | Rivera-Molina F.,Yale University | Novick P.,University of California at San Diego
Annual Review of Biochemistry | Year: 2012

Members of the Rab or ARFSar branches of the Ras GTPase superfamily regulate almost every step of intracellular membrane traffic. A rapidly growing body of evidence indicates that these GTPases do not act as lone agents but are networked to one another through a variety of mechanisms to coordinate the individual events of one stage of transport and to link together the different stages of an entire transport pathway. These mechanisms include guanine nucleotide exchange factor (GEF) cascades, GTPase-activating protein (GAP) cascades, effectors that bind to multiple GTPases, and positive-feedback loops generated by exchange factor-effector interactions. Together these mechanisms can lead to an ordered series of transitions from one GTPase to the next. As each GTPase recruits a unique set of effectors, these transitions help to define changes in the functionality of the membrane compartments with which they are associated. © 2012 by Annual Reviews. All rights reserved.

Ito K.,Gunma University
Nature Reviews Urology | Year: 2014

Prostate cancer incidence and mortality in most native Asian populations have gradually increased, but are around one-third lower than in corresponding Asian-American cohorts, which are themselves lower than the rates observed in other American cohorts. Although genetic and environmental factors, particularly a Western diet, could partially explain these differences, lower exposure to PSA screening in Asian individuals might be a major contributing factor. Genetic features and diet are, however, unlikely to differ substantially within the same region of Asia, and age-stratified PSA levels in men from various Asian countries are almost identical; therefore, variation in the epidemiology of prostate cancer among native Asian populations might be attributable to differences in access to PSA testing, urology clinics, and available therapies. Conversely, the proportion of patients with metastatic prostate cancer is substantially higher even in the more developed Asian countries than in migratory Asian populations residing in Western countries and in Westerners. Consequently, the most appropriate approaches to the management of prostate cancer in Asian countries probably also differ, and therefore individualized prostate cancer screening and treatment strategies based on the epidemiological features and socioeconomic status of each country are needed. © 2014 Macmillan Publishers Limited. All rights reserved.

Koike H.,Gunma University
Journal of cancer research and clinical oncology | Year: 2014

Mammalian target of rapamycin inhibitor has exhibited promising anticancer activity for the treatment of renal cell carcinoma (RCC). However, many patients acquire resistance to therapeutic agents leading to treatment failure. The objective of this study was to determine whether treatment with YM155, a novel small molecule inhibitor of survivin, could reverse rapamycin resistance in a rapamycin-resistant RCC. We induced a rapamycin-resistant clear cell carcinoma cell line (Caki-1-RapR). We showed that survivin gene expression was significantly up-regulated in Caki-1-RapR compared with that in its parent cells (Caki-1). Therefore, we hypothesized that targeting of survivin in Caki-1-RapR could reverse the resistant phenotype in tumor cells, thereby enhancing the therapeutic efficacy of rapamycin. We used both in vitro and in vivo models to test the efficacy of YM155 either as a single agent or in combination with rapamycin. In Caki-1-RapR cells, YM155 significantly decreased survivin gene and protein expression levels and cell proliferation in a dose-dependent manner in vitro. In addition, YM155 treatment significantly reversed rapamycin resistance in cancer cells. In a nude mouse tumor xenograft model, YM155 significantly inhibited the growth of Caki-1-RapR tumor. In addition, YM155 significantly enhanced the antitumor effects of rapamycin in Caki-1-RapR tumor. Our results suggest a potentially novel strategy to use YM155 to overcome the resistance in tumor cells, thereby enhancing the effectiveness of molecular target therapy in RCC.

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