178 results on '"Michio Asahi"'
Search Results
2. BDNF/TRKB axis provokes EMT progression to induce cell aggressiveness via crosstalk with cancer-associated fibroblasts in human parotid gland cancer
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Kazumasa Moriwaki, Masaki Wada, Hiroko Kuwabara, Yusuke Ayani, Tetsuya Terada, Masaaki Higashino, Ryo Kawata, and Michio Asahi
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Medicine ,Science - Abstract
Abstract Parotid gland cancer (PGC) is a rare malignancy and its molecular characteristics remain poorly understood, which has precluded the development of effective drug therapies. Given the poor prognosis of many human cancers in which tropomyosin receptor kinase B (TRKB) is highly expressed, we investigated the involvement of brain-derived neurotrophic factor (BDNF)/TRKB pathway in PGC cells using clinical specimens and observed upregulation of TRKB and BDNF. In primary culture systems of patient-derived PGC cells and cancer-associated fibroblasts (CAFs), PGC cells co-cultured with CAFs exhibited significant upregulation of BDNF and epithelial-mesenchymal transition (EMT). Similar results were observed in PGC cells treated with conditioned medium from co-cultures of PGC cells with CAFs. Administration of TRK inhibitors suppressed BDNF-induced cell migration in PGC cells. Immunohistochemical and clinicopathological analyses of tumors from patients with PGC revealed that BDNF and TRKB were highly expressed in both tumor cells and stromal cells such as CAFs, and TRKB expression levels in PGC cells were significantly correlated with aggressive features, including vascular invasion, nodal metastasis, and poor prognosis. Collectively, these data suggest that the BDNF/TRKB pathway regulates PGC cell aggressiveness via crosstalk with CAFs and is a potential therapeutic target for PGC harboring invasive and metastatic features.
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- 2022
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3. O-GlcNAcylation-induced GSK-3β activation deteriorates pressure overload-induced heart failure via lack of compensatory cardiac hypertrophy in mice
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Mahito Matsuno, Shunichi Yokoe, Takehiro Nagatsuka, Hirofumi Morihara, Kazumasa Moriwaki, and Michio Asahi
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O-GlcNAcylation ,heart failure ,hypertrophy ,transverse aortic constriction (TAC) ,GSK-3β ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
O-GlcNAc transferase (OGT) modulates many functions of proteins via O-GlcNAcylation that adds O-linked β-N-acetylglucosamine (O-GlcNAc) to the serine/threonine residues of proteins. However, the role of O-GlcNAcylation in cardiac remodeling and function is not fully understood. To examine the effect of O-GlcNAcylation on pressure overload-induced cardiac hypertrophy and subsequent heart failure, transverse aortic constriction (TAC) surgery was performed in wild type (WT) and Ogt transgenic (Ogt-Tg) mice. Four weeks after TAC (TAC4W), the heart function of Ogt-Tg mice was significantly lower than that of WT mice (reduced fractional shortening and increased ANP levels). The myocardium of left ventricle (LV) in Ogt-Tg mice became much thinner than that in WT mice. Moreover, compared to the heart tissues of WT mice, O-GlcNAcylation of GSK-3β at Ser9 was increased and phosphorylation of GSK-3β at Ser9 was reduced in the heart tissues of Ogt-Tg mice, resulting in its activation and subsequent inactivation of nuclear factor of activated T cell (NFAT) activity. Finally, the thinned LV wall and reduced cardiac function induced by TAC4W in Ogt-Tg mice was reversed by the treatment of a GSK-3β inhibitor, TDZD-8. These results imply that augmented O-GlcNAcylation exacerbates pressure overload-induced heart failure due to a lack of compensatory cardiac hypertrophy via O-GlcNAcylation of GSK-3β, which deprives the phosphorylation site of GSK-3β to constantly inactivate NFAT activity to prevent cardiac hypertrophy. Our findings may provide a new therapeutic strategy for cardiac hypertrophy and subsequent heart failure.
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- 2023
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4. Non-thermal atmospheric-pressure plasma potentiates mesodermal differentiation of human induced pluripotent stem cells
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Mime Kobayashi, Kiichiro Tomoda, Hirofumi Morihara, Michio Asahi, Tetsuji Shimizu, and Shinya Kumagai
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Atmospheric-pressure plasma ,iPS cells ,Cell differentiation ,DNA damage ,Mesoderm ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Non-thermal atmospheric-pressure plasma has been used for biological applications, including sterilization and stimulation of cell growth and differentiation. Here, we demonstrate that plasma exposure influences the differentiation pattern of human induced pluripotent stem cells (hiPSCs). We treated hiPSCs with dielectric barrier-discharge air plasma and found an exposure dose that does not kill hiPSCs. Immunohistochemical staining for E-CADHERIN showed that the exposure affected cell-cell attachment and doubled the average size of the hiPSCs. Analysis of mRNAs in embryoid bodies (EBs) from plasma-treated hiPSCs revealed repression of ectoderm genes, including WNT1, and increased expression of mesoderm genes. Importantly, hiPSCs deficient in DNA repair only displayed minimal damage after plasma exposure. Collectively, our results suggest that plasma treatment can be another tool for directing the fate of pluripotent stem cells without disrupting their genomic integrity.
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- 2022
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5. Cardiac Regeneration by Statin‐Polymer Nanoparticle‐Loaded Adipose‐Derived Stem Cell Therapy in Myocardial Infarction
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Ryo Yokoyama, Masaaki Ii, Yasuhiko Tabata, Masaaki Hoshiga, Nobukazu Ishizaka, and Michio Asahi
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Adipose stem cells ,Cardiac ,Stem cell transplantation ,Tissue regeneration ,Medicine (General) ,R5-920 ,Cytology ,QH573-671 - Abstract
Abstract Clinical trials with autologous adipose‐derived stem cell (AdSC) therapy for ischemic heart diseases (IHDs) are ongoing. However, little is known about combinational therapeutic effect of AdSCs and statin poly(lactic‐co‐glycolic) acid (PLGA) nanoparticles on the ischemic myocardium. We investigated the hypothesis that statins, which have pleiotropic effects, augment the therapeutic potential of AdSCs and that AdSCs also act as drug delivery tools. Simvastatin‐conjugated nanoparticles (SimNPs) significantly promoted migration activity without changing proliferation activity and upregulated growth factor gene expression in vitro. A small number of intravenously administered SimNP‐loaded AdSCs (10,000 cells per mouse) improved cardiac function following myocardial infarction, inducing endogenous cardiac regeneration in the infarcted myocardium. The de novo regenerated myocardium was thought to be derived from epicardial cells, which were positive for Wilms' tumor protein 1 expression. These findings were attributed to the sustained, local simvastatin release from the recruited SimNP‐loaded AdSCs in the infarcted myocardium rather than to the direct contribution of recruited AdSCs to tissue regeneration. SimNP‐loaded AdSCs may lead to a novel somatic stem cell therapy for IHDs. Stem Cells Translational Medicine 2019;8:1055–1067
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- 2019
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6. Induced 2C Expression and Implantation-Competent Blastocyst-like Cysts from Primed Pluripotent Stem Cells
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Cody Kime, Hiroshi Kiyonari, Satoshi Ohtsuka, Eiko Kohbayashi, Michio Asahi, Shinya Yamanaka, Masayo Takahashi, and Kiichiro Tomoda
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Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Summary: Soon after fertilization, the few totipotent cells of mammalian embryos diverge to form a structure called the blastocyst (BC). Although numerous cell types, including germ cells and extended-pluripotency stem cells, have been developed from pluripotent stem cells (PSCs) in vitro, generating functional BCs only from PSCs remains elusive. Here, we describe induced self-organizing 3D BC-like cysts (iBLCs) generated from mouse PSC culture. Resembling natural BCs, iBLCs have a blastocoel-like cavity and were formed with outer cells expressing trophectoderm lineage markers and with inner cells expressing pluripotency markers. iBLCs transplanted to pseudopregnant mice uteruses implanted, induced decidualization, and exhibited growth and development before resorption, demonstrating that iBLCs are implantation competent. iBLC precursor intermediates required the transcription factor Prdm14 and concomitantly activated the totipotency-related cleavage-stage MERVL reporter and 2C genes. Thus, our system may contribute to the understanding of molecular mechanisms underpinning totipotency, embryogenesis, and implantation. : In this article, Kime and Tomoda worked with collaborators to expand their previous studies increasing primed pluripotent stem cell potency with defined media cell reprogramming. They induced unique 2C-like cells with the potential to self-organize blastocyst-like cysts that can implant and develop in utero for several days until resorbed. Keywords: pluripotent stem cells, early embryo, implantation, cell biology, totipotency, reproduction, cell plasticity, blastocyst, reprogramming
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- 2019
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7. Sufficient therapeutic effect of cryopreserved frozen adipose-derived regenerative cells on burn wounds
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Yasuhiko Kaita, Takehiko Tarui, Hideaki Yoshino, Takeaki Matsuda, Yoshihiro Yamaguchi, Takatoshi Nakagawa, Michio Asahi, and Masaaki Ii
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Medicine (General) ,R5-920 ,Cytology ,QH573-671 - Abstract
Introduction: The purpose of this study was to evaluate whether cryopreserved (frozen) adipose-derived regenerative cells (ADRCs) have a therapeutic effect on burn wound healing as well as freshly isolated (fresh) ADRCs. Methods: Full thickness burns were created on dorsum of nude mice and burn wound was excised. The wound was covered by artificial dermis with; (i) fresh ADRCs, (ii) frozen ADRCs, and (iii) PBS (control). The assessment for wound healing was performed by morphological, histopathological and immunohistochemical analyses. Results: In vivo analyses exhibited the significant therapeutic effect of frozen ADRCs on burn wound healing up to the similar or higher level of fresh ADRCs. There were significant differences of wound closure, epithelized tissue thickness, and neovascularization between the treatment groups and control group. Although there was no significant difference of therapeutic efficacy between fresh ADRC group and frozen ADRC group, frozen ADRCs improved burn wound healing process in dermal regeneration with increased great type I collagen synthesis compared with fresh ADRCs. Conclusions: These findings indicate that frozen ADRCs allow us to apply not only quickly but also for multiple times, and the cryopreserved ADRCs could therefore be useful for the treatment of burn wounds in clinical settings. Keywords: Burn, Stem cells, Wound healing
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- 2019
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8. Iron derived from autophagy-mediated ferritin degradation induces cardiomyocyte death and heart failure in mice
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Jumpei Ito, Shigemiki Omiya, Mara-Camelia Rusu, Hiromichi Ueda, Tomokazu Murakawa, Yohei Tanada, Hajime Abe, Kazuki Nakahara, Michio Asahi, Manabu Taneike, Kazuhiko Nishida, Ajay M Shah, and Kinya Otsu
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autophagy ,iron ,necrosis ,ferritin ,heart failure ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Heart failure is a major public health problem, and abnormal iron metabolism is common in patients with heart failure. Although iron is necessary for metabolic homeostasis, it induces a programmed necrosis. Iron release from ferritin storage is through nuclear receptor coactivator 4 (NCOA4)-mediated autophagic degradation, known as ferritinophagy. However, the role of ferritinophagy in the stressed heart remains unclear. Deletion of Ncoa4 in mouse hearts reduced left ventricular chamber size and improved cardiac function along with the attenuation of the upregulation of ferritinophagy-mediated ferritin degradation 4 weeks after pressure overload. Free ferrous iron overload and increased lipid peroxidation were suppressed in NCOA4-deficient hearts. A potent inhibitor of lipid peroxidation, ferrostatin-1, significantly mitigated the development of pressure overload-induced dilated cardiomyopathy in wild-type mice. Thus, the activation of ferritinophagy results in the development of heart failure, whereas inhibition of this process protects the heart against hemodynamic stress.
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- 2021
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9. Intravenously Injected Pluripotent Stem Cell–derived Cells Form Fetomaternal Vasculature and Prevent Miscarriage in Mouse
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Atsushi Daimon, Hirofumi Morihara, Kiichiro Tomoda, Natsuko Morita, Yoshinori Koishi, Kazuyoshi Kanki, Masahide Ohmichi, and Michio Asahi
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Medicine - Abstract
Miscarriage is the most common complication of pregnancy, and about 1% of pregnant women suffer a recurrence. Using a widely used mouse miscarriage model, we previously showed that intravenous injection of bone marrow (BM)-derived endothelial progenitor cells (EPCs) may prevent miscarriage. However, preparing enough BM-derived EPCs to treat a patient might be problematic. Here, we demonstrated the generation of mouse pluripotent stem cells (PSCs), propagation of sufficient PSC-derived cells with endothelial potential (PSC-EPs), and intravenous injection of the PSC-EPs into the mouse miscarriage model. We found that the injection prevented miscarriage. Three-dimensional reconstruction images of the decidua after tissue cleaning revealed robust fetomaternal neovascularization induced by the PSC-EP injection. Additionally, the injected PSC-EPs directly formed spiral arteries. These findings suggest that intravenous injection of PSC-EPs could become a promising remedy for recurrent miscarriage.
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- 2020
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10. GABAB receptor regulates proliferation in the high-grade chondrosarcoma cell line OUMS-27 via apoptotic pathways
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Kiyoto Kanbara, Yoshinori Otsuki, Masahito Watanabe, Syunichi Yokoe, Yoshiaki Mori, Michio Asahi, and Masashi Neo
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Chondrosarcoma ,GABAB receptor ,Akt signaling ,Whole cell patch clamp ,Ca2+ channel ,Apoptosis ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background High-grade chondrosarcoma, which has a high incidence of local recurrence and pulmonary metastasis despite surgical resection, is associated with poor prognosis. Therefore, new and effective adjuvant therapies are urgently required for this disease. Gamma-aminobutyric acid (GABA), which acts as a neurotrophic factor during nervous system development, is related to the proliferation and migration of certain cancer cells. The GABAergic system, which is composed of GABA, the GABA-synthesizing enzyme glutamic acid decarboxylase (GAD), and GABA receptors, has an important function in nerve growth and development of neural crest. Therefore, the GABAergic system may play important functional roles in the proliferation of chondrosarcoma cells, which are derived from neural crest cells. We examined the anti-tumor effects of the GABAergic system on a chondrosarcoma cell line. Methods We evaluated the underlying mechanisms of the anti-tumor effects of the GABAergic system, such as the involvement of different signaling pathways, apoptosis, and cell cycle arrest, in the high-grade chondrosarcoma cell line OUMS-27. In addition, we performed whole-cell patch-clamp recordings for Ca2+ currents and evaluated the changes in intracellular Ca2+ concentration via Ca2+ channels, which are related to the GABAB receptor in high-grade chondrosarcoma cells. Results The GABAB receptor antagonist CGP had anti-tumor effects on high-grade chondrosarcoma cells in a dose-dependent manner. The activities of caspase 3 and caspase 9 were significantly elevated in CGP-treated cells compared to in untreated cells. The activity of caspase 8 did not differ significantly between untreated cells and CGP-treated cells. However, caspase 8 tended to be up-regulated in CGP-treated cells. The GABAB receptor antagonist exhibited anti-tumor effects at the G1/S cell cycle checkpoint and induced apoptosis via dual inhibition of the PI3/Akt/mTOR and MAPK signaling pathways. Furthermore, the changes in intracellular Ca2+ via GABAB receptor-related Ca2+ channels inhibited the proliferation of high-grade chondrosarcoma cells by inducing and modulating apoptotic pathways. Conclusions The GABAB receptor antagonist may improve the prognosis of high-grade chondrosarcoma by exerting anti-tumor effects via different signaling pathways, apoptosis, cell cycle arrest, and Ca2+ channels in high-grade chondrosarcoma cells.
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- 2018
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11. Autophagy deficiency exacerbates colitis through excessive oxidative stress and MAPK signaling pathway activation.
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Minori Kubota, Kazuki Kakimoto, Takatoshi Nakagawa, Eiko Koubayashi, Kei Nakazawa, Hideki Tawa, Yuki Hirata, Toshihiko Okada, Ken Kawakami, Akira Asai, Shuhei Hosomi, Toshihisa Takeuchi, Shinya Fukunishi, Takuya Inoue, Michio Asahi, and Kazuhide Higuchi
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Medicine ,Science - Abstract
BACKGROUND AND AIM:Autophagy is an essential process involved in the pathogenesis of inflammatory bowel disease (IBD). Although there are many data showing the roles of autophagy in intestinal epithelial cells (IECs), the mechanisms involved remain to be fully elucidated. We investigated the influence of autophagy in IECs on gastrointestinal tract inflammation. METHODS:Mice with conditional knockout of Atg5 in IECs (Atg5flox/flox/villin-Cre mice) were subjected to dextran sulfate sodium (DSS)-induced colitis and analyzed for colitis susceptibility. Additionally, we used Atg5-silenced rat IECs (IEC6shAtg5 cells) for in vitro assays. RESULTS:Sensitivity to DSS markedly increased in Atg5flox/flox/villin-Cre mice compared to that in wild-type mice. In IEC6shAtg5 cells, apoptosis was enhanced, and cell viability significantly decreased compared to IEC-6 cells. The expression of proinflammatory cytokines increased upon suppression of autophagy. Furthermore, silencing of Atg5 was associated with inflammation of IECs, activation of the mitogen-activated protein kinase (MAPK) signaling pathway by the intracellular reactive oxygen species accumulation, and NF-κB p65 phosphorylation. CONCLUSIONS:Autophagy in IECs plays an essential role in the maintenance of intestinal homeostasis, and autophagy deficiency triggers inflammation. Development of methods targeting autophagy might be beneficial in the treatment of IBD.
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- 2019
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12. Sonic Hedgehog signaling regulates vascular differentiation and function in human CD34 positive cells
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Kurando Kanaya, Masaaki Ii, Teiji Okazaki, Toru Nakamura, Miki Horii-Komatsu, Cantas Alev, Hiroshi Akimaru, Atsuhiko Kawamoto, Hidetoshi Akashi, Hiroyuki Tanaka, Michio Asahi, and Takayuki Asahara
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Biology (General) ,QH301-705.5 - Abstract
Identification of pivotal factors potentially present in the in situ environment and capable of influencing the function of CD34+ cells, which can be used for autologous cell therapy, is of paramount interest. SHh is one of the morphogens essential for embryonic vascular development as well as postnatal neovascularization, and the activation of SHh signaling with angiogenic and vascular differentiation responses in CD34+ cells by SHh treatment differed depending on the G-CSF treatment or the background disease. SHh enhanced the migration, proliferation, adhesion, and EPC colony forming capacities of G-CSF mobilized CD34+ cells, increasing the vasculogenic/angiogenic potential for neovascularization. An increase in the differentiation potential of CD34+ cells toward vascular lineages was demonstrated with SHh treatment involving TGFβ signaling pathway. The SHh-activated G-CSF mobilized CD34+ cells directly contributed to vascular regeneration while non-activated CD34+ cells showed a lower regenerative capacity in a mouse ischemic hindlimb model. SHh signaling regulates human CD34+ cell fate and function, and may potentiate the therapeutic effect of G-CSF mobilized CD34+ cells on ischemic diseases.
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- 2015
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13. Bone Marrow-Derived Endothelial Progenitor Cells Reduce Recurrent Miscarriage in Gestation
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Kazuyoshi Kanki, Masaaki Ii M.D., Ph.D., Yoshito Terai, Masahide Ohmichi, and Michio Asahi
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Medicine - Abstract
Bone marrow-derived endothelial progenitor cells (EPCs) have been shown to contribute to not only angiogenesis in ischemic tissue but also neovascularization in uterine endometrium formation. Reduced neovascularization and elevation of serum soluble Flt1, a functional blockage of VEGF, in the development of placenta is thought to be one of the major causes of repeated miscarriages in gestation. We then examined whether transfusion of VEGF-expressing extrinsic EPCs prevented frequent miscarriage via its promotional effect on neovascularization with a VEGF–eNOS signaling pathway in a mouse miscarriage model. The results showed that systemic EPC transfusion significantly reduced the rate of miscarriage, and EPCs were frequently observed in the miscarriage placenta. In contrast, only a few EPCs were detected in the placenta of normal gestation. The vascular pattern was irregular, and vessel size was small in the miscarriage placenta compared with that of normal gestation. The placental vascular pattern in miscarriage tended to be normalized with increased vessel size up to a similar level as normal gestation by EPC recruitment. For the mechanistic insight, since soluble Flt1 inhibits EPC functions, it was suggested that the increased soluble Flt1 could suppress the recruited EPC functional activity in the miscarriage placenta. In vitro experiments by soluble Flt1 treatment in cultured EPCs suggested that the vascular abnormality could be partly due to the inhibition of eNOS expression by the increased amounts of soluble Flt1. These findings from animal experiments indicated that autologous EPC therapy may be a novel therapy to prevent miscarriage in high-risk pregnancies, such as preeclampsia.
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- 2016
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14. Phospholamban Is Downregulated by pVHL-Mediated Degradation through Oxidative Stress in Failing Heart
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Shunichi Yokoe and Michio Asahi
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cardiac function ,phospholamban ,calcium signaling ,hypoxia ,ubiquitination ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The E3 ubiquitin ligase, von Hippel–Lindau (VHL), regulates protein expression by polyubiquitination. Although the protein VHL (pVHL) was reported to be involved in the heart function, the underlying mechanism is unclear. Here, we show that pVHL was upregulated in hearts from two types of genetically dilated cardiomyopathy (DCM) mice models. In comparison with the wild-type mouse, both DCM mice models showed a significant reduction in the expression of phospholamban (PLN), a potent inhibitor of sarco(endo)plasmic reticulum Ca2+-ATPase, and enhanced interaction between pVHL and PLN. To clarify whether pVHL is involved in PLN degradation in failing hearts, we used carbonylcyanide m-chlorophenylhydrazone (CCCP), a mitochondrial membrane potential (MMP)-lowering reagent, to mimic the heart failure condition in PLN-expressing HEK293 cells and found that CCCP treatment resulted in PLN degradation and increased interaction between PLN and pVHL. However, these effects were reversed with the addition of N-acetyl-l-cysteine. Furthermore, the co-transfection of VHL and PLN in HEK293 cells decreased PLN expression under oxidative stress, whereas knockdown of VHL increased PLN expression both under normal and oxidative stress conditions. Together, we propose that oxidative stress upregulates pVHL expression to induce PLN degradation in failing hearts.
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- 2017
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15. Augmented O-GlcNAcylation exacerbates right ventricular dysfunction and remodeling via enhancement of hypertrophy, mitophagy, and fibrosis in mice exposed to long-term intermittent hypoxia
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Shunichi, Yokoe, Tetsuya, Hayashi, Takatoshi, Nakagawa, Ryuji, Kato, Yoshio, Ijiri, Takehiro, Yamaguchi, Yasukatsu, Izumi, Minoru, Yoshiyama, and Michio, Asahi
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Physiology ,Internal Medicine ,Cardiology and Cardiovascular Medicine - Abstract
Previously, we showed that augmented O-linked N-acetylglucosaminylation (O-GlcNAcylation) mitigates cardiac remodeling in O-GlcNAc transferase-transgenic (Ogt-Tg) mice exposed to acute (2-week) intermittent hypoxia (IH) by suppressing nuclear factor of activated T cells (NFAT) and nuclear factor kappa B (NF-κB) via the O-GlcNAcylation of glycogen synthase kinase 3 beta (GSK-3β) and NF-κB p65. Because this effect is time dependent, we exposed Ogt-Tg mice to IH for 4 weeks (IH4W) in the present study. O-GlcNAcylation was significantly enhanced in Ogt-Tg mice vs. wild-type (WT) mice exposed to normoxia and IH4W. Total O-GlcNAcylation levels were significantly increased in WT and Ogt-Tg mice after IH4W vs. normoxia. After IH4W, Ogt-Tg mice displayed significantly exacerbated signs of cardiac hypertrophy and fibrosis in the right ventricles (RVs) but not the left ventricles (LVs). Echocardiography revealed IH4W-induced right ventricular dysfunction. Phosphorylated GSK-3β levels were increased in Ogt-Tg mice vs. WT mice after IH4W, whereas phosphorylated NF-κB p65 levels were unaffected. Mitophagy, which is associated with cardiac dysfunction, was increased in the RVs of Ogt-Tg mice after IH4W. Furthermore, the levels of phosphorylated dynamin-related protein 1 (p-Drp1) were significantly increased, and the expression of mitofusin-2 (MFN2) was significantly decreased. In human embryonic kidney cells, mitochondrial uncoupler-induced mitochondrial dysfunction was accelerated in Ogt-overexpressing cells. In addition to increasing the levels of phosphorylated Smad2, IH4W promoted cardiac fibrosis in the RVs of Ogt-Tg mice. Thus, augmented O-GlcNAcylation may aggravate IH4W-induced right ventricular dysfunction and remodeling by promoting hypertrophy, mitophagy, and fibrosis via GSK-3β inactivation, an increased p-Drp-1/MFN2 ratio, and Smad2 activation, respectively.
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- 2022
16. S2 from Augmented TME O-GlcNAcylation Promotes Tumor Proliferation through the Inhibition of p38 MAPK
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Michio Asahi and Kazumasa Moriwaki
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Supplemental Figure 2. Spontaneous apoptosis in tumor tissues does not differ significantly between WT and Ogt-Tg/+ mice.
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- 2023
17. Supplementary Figure 1 from The Asn418-Linked N-Glycan of ErbB3 Plays a Crucial Role in Preventing Spontaneous Heterodimerization and Tumor Promotion
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Naoyuki Taniguchi, Eiji Miyoshi, Daisuke Osumi, Wei Li, Seung Ho Lee, Michio Asahi, Motoko Takahashi, and Shunichi Yokoe
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Supplementary Figure 1 from The Asn418-Linked N-Glycan of ErbB3 Plays a Crucial Role in Preventing Spontaneous Heterodimerization and Tumor Promotion
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- 2023
18. Supplementary Figure Legend from The Asn418-Linked N-Glycan of ErbB3 Plays a Crucial Role in Preventing Spontaneous Heterodimerization and Tumor Promotion
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Naoyuki Taniguchi, Eiji Miyoshi, Daisuke Osumi, Wei Li, Seung Ho Lee, Michio Asahi, Motoko Takahashi, and Shunichi Yokoe
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Supplementary Figure Legend from The Asn418-Linked N-Glycan of ErbB3 Plays a Crucial Role in Preventing Spontaneous Heterodimerization and Tumor Promotion
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- 2023
19. Data from The Asn418-Linked N-Glycan of ErbB3 Plays a Crucial Role in Preventing Spontaneous Heterodimerization and Tumor Promotion
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Naoyuki Taniguchi, Eiji Miyoshi, Daisuke Osumi, Wei Li, Seung Ho Lee, Michio Asahi, Motoko Takahashi, and Shunichi Yokoe
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ErbB2 and ErbB3, two members of the ErbB family, form a high-affinity heregulin coreceptor that elicits potent mitogenic and transforming signals, and clinical studies indicate that these receptors play an important role in tumor incidence and progression. To determine whether N-glycosylation is involved in the function of ErbB3, a series of human ErbB3 molecules devoid of N-glycans were prepared and transfected to Flp-In-CHO cells for stable expression. A cross-linking study showed that the Asn418 to Gln mutant (N418Q) of ErbB3 underwent autodimerization without its ligand, heregulin. The wild-type or N418Q mutant of ErbB3 was next coexpressed with ErbB2 in Flp-In-CHO cells, and the effect of N-glycan on heterodimerization was examined. The N418Q mutant of ErbB3 was autodimerized with ErbB2 without ligand stimulation, and receptor tyrosine phosphorylation and subsequent extracellular signal-regulated kinase (ERK) and Akt phosphorylation were promoted in the absence of heregulin. A cell proliferation assay and a soft agar colony formation assay showed that the N418Q mutant of ErbB3 coexpressed with ErbB2 promoted cell proliferation and colony formation in soft agar in an ERK- and Akt-dependent manner. The mutation also promoted the growth of tumors in athymic mice when injected s.c. These findings suggest that the Asn418-linked N-glycan in ErbB3 plays an essential role in regulating receptor heterodimerization with ErbB2 and might have an effect on transforming activity. [Cancer Res 2007;67(5):1935–42]
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- 2023
20. Supplementary Table 1 from The Asn418-Linked N-Glycan of ErbB3 Plays a Crucial Role in Preventing Spontaneous Heterodimerization and Tumor Promotion
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Naoyuki Taniguchi, Eiji Miyoshi, Daisuke Osumi, Wei Li, Seung Ho Lee, Michio Asahi, Motoko Takahashi, and Shunichi Yokoe
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Supplementary Table 1 from The Asn418-Linked N-Glycan of ErbB3 Plays a Crucial Role in Preventing Spontaneous Heterodimerization and Tumor Promotion
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- 2023
21. Rivaroxaban Attenuates Right Ventricular Remodeling in Rats with Pulmonary Arterial Hypertension
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Hong Wu, Minoru Yoshiyama, Yoshikatsu Okada, Yasukatsu Izumi, Takehiro Yamaguchi, Yoshio Ijiri, Hideki Imano, Atsuo Nomura, Yudai Yamaguchi, Takashi Nakano, Ryuji Kato, Tetsuya Hayashi, Maki Tamura, and Michio Asahi
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Male ,0301 basic medicine ,MAPK/ERK pathway ,Indoles ,Heart Ventricles ,Cell Culture Techniques ,Pharmaceutical Science ,Blood Pressure ,Pharmacology ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,Rivaroxaban ,Extracellular ,Animals ,Humans ,Medicine ,Pyrroles ,Extracellular Signal-Regulated MAP Kinases ,Hypoxia ,Ventricular remodeling ,Pulmonary Arterial Hypertension ,Ventricular Remodeling ,business.industry ,Kinase ,JNK Mitogen-Activated Protein Kinases ,NF-kappa B ,Endothelial Cells ,General Medicine ,Hypoxia (medical) ,medicine.disease ,In vitro ,Disease Models, Animal ,030104 developmental biology ,Blood pressure ,030220 oncology & carcinogenesis ,medicine.symptom ,business ,Factor Xa Inhibitors ,medicine.drug - Abstract
Pulmonary arterial hypertension (PAH) is a progressive condition that frequently results in right ventricular (RV) remodeling. The objectives of this study are to investigate effects of rivaroxaban on RV remodeling in a rat model of PAH, created with Sugen5416 and chronic hypoxia, and the in vitro effects of rivaroxaban on human cardiac microvascular endothelial cells (HCMECs). To create the PAH model, male Sprague-Dawley rats were subcutaneously injected with Sugen5416 (20 mg/kg) and exposed to 2 weeks of hypoxia (10% O2), followed by 2 weeks of exposure to normoxia. The animals were then divided into 2 groups with or without administration of rivaroxaban (1.2 mg/kg/day) for a further 4 weeks. HCMECs were cultured under hypoxic conditions (37°C, 1% O2, 5% CO2) with Sugen5416 and with or without rivaroxaban. In the model rats, RV systolic pressure and Fulton index increased by hypoxia with Sugen5416 were significantly decreased when treated with rivaroxaban. In HCMECs, hypoxia with Sugen5416 increased the expression of protease-activated receptor-2 (PAR-2) and the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and nuclear factor-kappa B (NF-κB), while treatment with rivaroxaban significantly suppressed the expression of these proteins. Rivaroxaban attenuated RV remodeling in a rat model of PAH by reducing ERK, JNK and NF-κB activation. Rivaroxaban has the possibility of providing additive effects on RV remodeling in patients with PAH.
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- 2021
22. Fluctuation in O-GlcNAcylation inactivates STIM1 to reduce store-operated calcium ion entry via down-regulation of Ser621 phosphorylation
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Takatoshi Nakagawa, Francisco Javier Martin-Romero, Kiichiro Tomoda, Shunichi Yokoe, Atsuo Nomura, and Michio Asahi
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inorganic chemicals ,0301 basic medicine ,030102 biochemistry & molecular biology ,HEK 293 cells ,chemistry.chemical_element ,STIM1 ,Cell Biology ,Transfection ,Calcium ,Biochemistry ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,chemistry ,Downregulation and upregulation ,Transferase ,Phosphorylation ,Protein phosphorylation ,Molecular Biology - Abstract
Stromal interaction molecule 1 (STIM1) plays a pivotal role in store-operated Ca2+ entry (SOCE), an essential mechanism in cellular calcium signaling and in maintaining cellular calcium balance. Because O-GlcNAcylation plays pivotal roles in various cellular function, we examined the effect of fluctuation in STIM1 O-GlcNAcylation on SOCE activity. We found that both increase and decrease in STIM1 O-GlcNAcylation impaired SOCE activity. To determine the molecular basis, we established STIM1-knockout HEK293 (STIM1-KO-HEK) cells using the CRISPR/Cas9 system and transfected STIM1 WT (STIM1-KO-WT-HEK), S621A (STIM1-KO-S621A-HEK), or T626A (STIM1-KO-T626A-HEK) cells. Using these cells, we examined the possible O-GlcNAcylation sites of STIM1 to determine whether the sites were O-GlcNAcylated. Co-immunoprecipitation analysis revealed that Ser621 and Thr626 were O-GlcNAcylated and that Thr626 was O-GlcNAcylated in the steady state but Ser621 was not. The SOCE activity in STIM1-KO-S621A-HEK and STIM1-KO-T626A-HEK cells was lower than that in STIM1-KO-WT-HEK cells because of reduced phosphorylation at Ser621. Treatment with the O-GlcNAcase inhibitor Thiamet G or O-GlcNAc transferase (OGT) transfection, which increases O-GlcNAcylation, reduced SOCE activity, whereas treatment with the OGT inhibitor ST045849 or siOGT transfection, which decreases O-GlcNAcylation, also reduced SOCE activity. Decrease in SOCE activity due to increase and decrease in O-GlcNAcylation was attributable to reduced phosphorylation at Ser621. These data suggest that both decrease in O-GlcNAcylation at Thr626 and increase in O-GlcNAcylation at Ser621 in STIM1 lead to impairment of SOCE activity through decrease in Ser621 phosphorylation. Targeting STIM1 O-GlcNAcylation could provide a promising treatment option for the related diseases, such as neurodegenerative diseases.
- Published
- 2020
23. Exacerbation of autoimmune myocarditis by an immune checkpoint inhibitor is dependent on its time of administration in mice
- Author
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Hirofumi Morihara, Kenjiro Tsuruoka, Shigeo Wakabayashi, Ninso Matsunaga, Michio Asahi, Akihisa Imagawa, Yasuhito Fujisaka, and Isao Goto
- Subjects
Myocarditis ,Autoimmunity ,030204 cardiovascular system & hematology ,medicine.disease_cause ,Autoimmune Diseases ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,medicine ,Animals ,Humans ,030212 general & internal medicine ,Interleukin 6 ,Immune Checkpoint Inhibitors ,Mice, Inbred BALB C ,biology ,Cluster of differentiation ,business.industry ,medicine.disease ,Disease Models, Animal ,Collagen, type I, alpha 1 ,Immunology ,biology.protein ,Antibody ,Cardiology and Cardiovascular Medicine ,business ,Cardiac Myosins ,Infiltration (medical) - Abstract
Background Although immune checkpoint inhibitors (ICIs) have made an immense breakthrough in cancer therapeutics, they can exert unique, immune-related adverse events. Among them, myocarditis is less frequent, but it is serious and often follows a lethal course. Methods To examine the changes in cardiac autoimmunity after ICI administration, we developed a mouse experimental autoimmune myocarditis (EAM) model via intraperitoneal administration of murine α-cardiac myosin heavy chain (MyHC-α) fragment. Thereafter, the mouse anti-PD-1 antibody (mPD1ab) was administered at two time points, subsequent to and concurrent with MyHC-α fragment administration. Results Severe EAM developed in 3 weeks; wide inflammatory lesions were observed in the cardiac sections. Furthermore, inflammatory/fibrotic genes, such as interleukin 1β, interleukin 6, and collagen 1, were upregulated, although the cardiac function was not significantly affected. The subsequent administration of mPD1ab at 2 weeks post administration of the first MyHC-α fragment exacerbated EAM, whereas the administration of mPD1ab concurrent with MyHC-α fragment administration did not exacerbate EAM. The subsequent administration of mPD1ab significantly increased the infiltration of cluster of differentiation (CD)4- and F4/80-positive cells, whereas the concurrent administration of mPD1ab significantly decreased the infiltration of CD4-positive cells, indicating that the concurrent and subsequent administration of mPD1ab had opposite effects on immune/inflammatory cell infiltration. Conclusions These data suggest that the appearance of ICI-induced autoimmune myocarditis might be related to autoimmune system activity before ICI administration. Although ICIs do not adversely affect patients with normal immune systems, we propose that ICI administration should be avoided in patients with autoimmune disorders.
- Published
- 2020
24. Enhancement of O‑linked N‑acetylglucosamine modification promotes metastasis in patients with colorectal cancer and concurrent type 2 diabetes mellitus
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Yutaka Naka, Eiko Kobayashi, Yuki Hirata, Takatoshi Nakagawa, Kazuhisa Uchiyama, Kazuhide Higuchi, Yasuyoshi Tanaka, Yuka Kawasaki, Takuya Inoue, Yoshinobu Hirose, Toshihisa Takeuchi, Kazuki Kakimoto, Michio Asahi, Ken Kawakami, Hideki Tawa, Shinya Fukunishi, and Toshihiko Okada
- Subjects
0301 basic medicine ,Cancer Research ,endocrine system diseases ,Oncogene ,business.industry ,Colorectal cancer ,nutritional and metabolic diseases ,Type 2 Diabetes Mellitus ,Cancer ,Cell cycle ,medicine.disease ,Molecular medicine ,Metastasis ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Oncology ,Downregulation and upregulation ,030220 oncology & carcinogenesis ,Cancer research ,Medicine ,business - Abstract
Reversible post-translational modification of serine and threonine residues by O-linked N-acetylglucosamine (O-GlcNAc), termed O-GlcNAcylation has been indicated to regulate the activities of a number of different proteins. Augmented O-GlcNAcylation contributes to the etiologies of type 2 diabetes mellitus (T2DM) and cancer. Moreover, diabetic conditions increase the risk of colorectal cancer. However, the effect of O-GlcNAcylation in patients with colorectal cancer and concurrent T2DM has not been elucidated. The current study evaluated the level of O-GlcNAcylation in patients with colorectal cancer with or without T2DM. Notably, O-GlcNAcylation levels were significantly higher in tissues from patients with T2DM compared with those in patients without T2DM, and higher in cancer tissues compared with corresponding adjacent tissues. O-GlcNAcylation and cancer stage were more strongly correlated in cancer tissues from patients with T2DM compared with those from patients without T2DM. Additionally, distant metastasis was significantly correlated with O-GlcNAcylation in cancer tissues from patients with T2DM. β-catenin levels in colorectal cancer tissues were the highest in patients with advanced-stage cancer and concurrent T2DM. In SW480 human colon cancer cells, thiamet G (TMG) treatment and OGA silencing, which increased O-GlcNAcylation, significantly increased β-catenin and SNAIL in high-glucose, but not during normal-glucose conditions. These data suggest that O-GlcNAcylation is closely associated with distant metastasis, most likely through upregulation of the β-catenin/SNAIL signaling pathway in colorectal cancer patients with T2DM.
- Published
- 2020
25. O-GlcNAcylation-mediated degradation of FBXL2 stabilizes FOXM1 to induce cancer progression
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Yasuhiro Ueda, Toshihisa Takeuchi, Michio Asahi, Kazuhide Higuchi, and Kazumasa Moriwaki
- Subjects
0301 basic medicine ,Cell signaling ,Acylation ,Biophysics ,Biochemistry ,Acetylglucosamine ,03 medical and health sciences ,0302 clinical medicine ,Ubiquitin ,Stomach Neoplasms ,Cell Line, Tumor ,medicine ,Humans ,Molecular Biology ,Transcription factor ,Cell Proliferation ,biology ,Protein Stability ,Chemistry ,Cell growth ,F-Box Proteins ,Forkhead Box Protein M1 ,Ubiquitination ,Cancer ,Cell Biology ,medicine.disease ,Cell biology ,Ubiquitin ligase ,030104 developmental biology ,030220 oncology & carcinogenesis ,Proteolysis ,Disease Progression ,biology.protein ,FOXM1 ,Degradation (geology) - Abstract
O-GlcNAcylation is a dynamic and reversible post-translational modification of cytonuclear molecules that regulates cellular signaling. Elevated O-GlcNAcylation is a general property of cancer and plays a critical role in cancer progression. We previously showed that the expression of FOXM1, a critical oncogenic transcription factor widely overexpressed in solid tumors, was elevated in MKN45 cells, a human gastric cancer cell line, by the O-GlcNAcase inhibitor Thiamet G (TMG), which induces augmented O-GlcNAcylation. Here, we identified FBXL2 E3 ubiquitin ligase as a new target of O-GlcNAcylation. Consistent with the results in MKN45 cells, FOXM1 expression was increased, accompanied by its decreased ubiquitination and degradation by TMG in the other gastric cancer cell lines, including NUGC-3 cells. We found that FBXL2 ubiquitinated FOXM1, and the interaction with FBXL2 and ubiquitination of FOXM1 were reduced by TMG in NUGC-3 cells. Interestingly, FBXL2 was also ubiquitinated, which was promoted by TMG in the cells. Moreover, FOXM1 expression and cell proliferation were reduced in FBXL2-induced NUGC-3 cells, and the reductions were attenuated by TMG, indicating that FOXM1 was stabilized by O-GlcNAcylation-mediated degradation of FBXL2 to induce cancer progression. These data suggest that elevated O-GlcNAcylation contributes to cancer progression by suppressing FBXL2-mediated degradation of FOXM1.
- Published
- 2020
26. Overexpression of Na+/H+ exchanger 1 specifically induces cell death in human iPS cells via sustained activation of the Rho kinase ROCK
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Kazumasa Moriwaki, Hirofumi Morihara, Shunichi Yokoe, Kiichiro Tomoda, Michio Asahi, Shigeo Wakabayashi, and Takatoshi Nakagawa
- Subjects
0301 basic medicine ,Programmed cell death ,030102 biochemistry & molecular biology ,Cell growth ,Chemistry ,Cellular differentiation ,Cell ,Cell Biology ,Biochemistry ,Cell biology ,03 medical and health sciences ,Cytosol ,030104 developmental biology ,medicine.anatomical_structure ,medicine ,Induced pluripotent stem cell ,Protein kinase A ,Molecular Biology ,Rho-associated protein kinase - Abstract
Understanding the specific properties of human induced pluripotent stem cells (iPSCs) is important for quality control of iPSCs. Having incidentally discovered that overexpression of plasma membrane Na+/H+ exchanger 1 (NHE1) induces cell death in iPSCs, we investigated the mechanism of NHE1-induced cell death. Doxycycline-induced NHE1 overexpression arrested cell growth, and nearly all cells were killed by a necrotic process within 72 h. NHE1 overexpression led to sustained activation of Rho-associated coiled-coil kinase (ROCK), accompanied by dramatic changes in cell shape, cell elongation, and swelling of peripheral cells in iPSC colonies, as well as marked stress fiber formation. The ROCK inhibitor Y27632 reduced NHE1-induced cell death. ROCK-dependent phenotypes were suppressed by a loss-of-function mutation of NHE1 and inhibited by an inhibitor of NHE1 activity, indicating that NHE1-mediated transport activity is required. Moreover, ROCK was activated by trimethylamine treatment–mediated cytosolic alkalinization and accumulated in the plasma membrane near NHE1 in peripheral iPSCs of cell colonies. By contrast, cell death did not occur in mesendoderm-like cells that had differentiated from iPSCs, indicating that the NHE1-mediated effects were specific for iPSCs. These results suggest that NHE1 overexpression specifically induces death of iPSCs via sustained ROCK activation, probably caused by an increase in local pH near NHE1. Finally, monensin, a Na+/H+ exchange ionophore, selectively killed iPSCs, suggesting that monensin could help eliminate iPSCs that remain after differentiation, a strategy that might be useful for improving regenerative medicine.
- Published
- 2019
27. TMEM182 maintains the activated state of Wnt/β-catenin signaling by increasing ILK and inhibits cardiac differentiation in human iPS cells
- Author
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Hirofumi Morihara, Shigeo Wakabayashi, and Michio Asahi
- Subjects
Applied Mathematics ,General Mathematics - Published
- 2022
28. Induced 2C Expression and Implantation-Competent Blastocyst-like Cysts from Primed Pluripotent Stem Cells
- Author
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Hiroshi Kiyonari, Masayo Takahashi, Satoshi Ohtsuka, Kiichiro Tomoda, Cody Kime, Michio Asahi, Eiko Kohbayashi, and Shinya Yamanaka
- Subjects
0301 basic medicine ,Cell Cycle Proteins ,Biochemistry ,Mice ,0302 clinical medicine ,Genes, Reporter ,cell biology ,totipotency ,implantation ,Induced pluripotent stem cell ,lcsh:QH301-705.5 ,Mice, Inbred ICR ,lcsh:R5-920 ,cell plasticity ,Totipotent ,RNA-Binding Proteins ,Cell Differentiation ,Preview ,Cell biology ,DNA-Binding Proteins ,medicine.anatomical_structure ,embryonic structures ,Female ,Stem cell ,pluripotent stem cells ,lcsh:Medicine (General) ,Cell type ,Embryonic Development ,Biology ,reproduction ,03 medical and health sciences ,early embryo ,Genetics ,medicine ,Animals ,Cell Lineage ,Blastocyst ,Adaptor Proteins, Signal Transducing ,blastocyst ,Lineage markers ,Uterus ,Embryogenesis ,Decidualization ,reprogramming ,YAP-Signaling Proteins ,030104 developmental biology ,lcsh:Biology (General) ,030217 neurology & neurosurgery ,Transcription Factors ,Developmental Biology - Abstract
Summary: Soon after fertilization, the few totipotent cells of mammalian embryos diverge to form a structure called the blastocyst (BC). Although numerous cell types, including germ cells and extended-pluripotency stem cells, have been developed from pluripotent stem cells (PSCs) in vitro, generating functional BCs only from PSCs remains elusive. Here, we describe induced self-organizing 3D BC-like cysts (iBLCs) generated from mouse PSC culture. Resembling natural BCs, iBLCs have a blastocoel-like cavity and were formed with outer cells expressing trophectoderm lineage markers and with inner cells expressing pluripotency markers. iBLCs transplanted to pseudopregnant mice uteruses implanted, induced decidualization, and exhibited growth and development before resorption, demonstrating that iBLCs are implantation competent. iBLC precursor intermediates required the transcription factor Prdm14 and concomitantly activated the totipotency-related cleavage-stage MERVL reporter and 2C genes. Thus, our system may contribute to the understanding of molecular mechanisms underpinning totipotency, embryogenesis, and implantation. : In this article, Kime and Tomoda worked with collaborators to expand their previous studies increasing primed pluripotent stem cell potency with defined media cell reprogramming. They induced unique 2C-like cells with the potential to self-organize blastocyst-like cysts that can implant and develop in utero for several days until resorbed. Keywords: pluripotent stem cells, early embryo, implantation, cell biology, totipotency, reproduction, cell plasticity, blastocyst, reprogramming
- Published
- 2019
29. Augmented O-GlcNAcylation attenuates intermittent hypoxia-induced cardiac remodeling through the suppression of NFAT and NF-κB activities in mice
- Author
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Takehiro Yamaguchi, Takatoshi Nakagawa, Tetsuya Hayashi, Ryuji Kato, Shunichi Yokoe, Kazumasa Moriwaki, Michio Asahi, Minoru Yoshiyama, Atsuo Nomura, Yoshio Ijiri, Yuichi Furukawa, and Yasukatsu Izumi
- Subjects
medicine.medical_specialty ,Physiology ,Transgene ,NF-κB ,NFAT ,Intermittent hypoxia ,030204 cardiovascular system & hematology ,medicine.disease_cause ,In vitro ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,chemistry ,Apoptosis ,Internal medicine ,Internal Medicine ,medicine ,Phosphorylation ,030212 general & internal medicine ,Cardiology and Cardiovascular Medicine ,Oxidative stress - Abstract
Type 2 diabetes mellitus (T2DM) has been reported to be associated with cardiac remodeling. Although O-GlcNAcylation is known to be elevated in diabetic and ischemic hearts, the effects of O-GlcNAcylation on cardiac remodeling induced by intermittent hypoxia (IH), such as sleep apnea syndrome (SAS), remain unknown. To evaluate the effects, we induced IH in wild-type (WT) and transgenic O-GlcNAc transferase (Ogt-Tg) mice. Two weeks of IH increased O-GlcNAcylation in the heart tissues of both strains of mice, whereas O-GlcNAcylation in Ogt-Tg mice was significantly higher than that in WT mice under both normoxic and IH conditions. WT mice exhibited cardiac remodeling after IH, whereas cardiac remodeling was significantly attenuated in Ogt-Tg mice. Oxidative stress and apoptosis increased after IH in both strains of mice, whereas the rate of increase in these processes in Ogt-Tg mice was significantly lower than that in WT mice. To examine the mechanism of cardiac remodeling attenuation in Ogt-Tg mice after IH, the effects of O-GlcNAcylation on the activities of the master regulators nuclear factor of activated T cells (NFAT) and NF-κB were determined. The O-GlcNAcylation of GSK-3β, a negative regulator of NFAT, was significantly increased in Ogt-Tg mice, whereas the phosphorylation of GSK-3β was reciprocally reduced. The same result was observed for NF-κB p65. An in vitro reporter assay showed that the augmentation of O-GlcNAcylation by an O-GlcNAcase inhibitor suppressed NFAT and NF-κB promoter activity. These data suggest that augmented O-GlcNAcylation mitigates IH-induced cardiac remodeling by suppressing NFAT and NF-κB activities through the O-GlcNAcylation of GSK-3β and NF-κB p65.
- Published
- 2019
30. Author response: Iron derived from autophagy-mediated ferritin degradation induces cardiomyocyte death and heart failure in mice
- Author
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Jumpei Ito, Kazuhiko Nishida, Yohei Tanada, Kazuki Nakahara, Hajime Abe, Hiromichi Ueda, Ajay M. Shah, Mara-Camelia Rusu, Manabu Taneike, Shigemiki Omiya, Tomokazu Murakawa, Michio Asahi, and Kinya Otsu
- Subjects
Ferritin ,biology ,Chemistry ,Heart failure ,Autophagy ,medicine ,biology.protein ,medicine.disease ,Cell biology - Published
- 2020
31. Phospholamban is degraded by parkin-mediated ubiquitination in failing heart
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Shunichi Yokoe and Michio Asahi
- Subjects
Applied Mathematics ,General Mathematics - Published
- 2022
32. The BDNF/TRKB pathway promotes EMT to induce parotid gland cancer cell aggressiveness via interaction with CAF
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Kazumasa Moriwaki, Hiroko Kuwabara, Yusuke Ayani, Masaaki Higashino, Tetsuya Terada, Ryo Kawata, and Michio Asahi
- Subjects
Applied Mathematics ,General Mathematics - Published
- 2022
33. Iron derived from ferritinophagy induces cardiomyocyte death and heart failure in mice
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Ito Jumpei, Kinya Otsu, and Michio Asahi
- Subjects
Applied Mathematics ,General Mathematics - Published
- 2022
34. SARAF and ALG-2 are degraded under the ER stress condition in heart failure
- Author
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Shunichi Yokoe and Michio Asahi
- Subjects
Applied Mathematics ,General Mathematics - Published
- 2022
35. Effect of TMEM182, a novel membrane protein, on muscle differentiation
- Author
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Hirofumi Morihara, Soichiro Furutani, Shigeo Wakabayashi, and Michio Asahi
- Subjects
Applied Mathematics ,General Mathematics - Published
- 2022
36. Fluctuation in
- Author
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Atsuo, Nomura, Shunichi, Yokoe, Kiichiro, Tomoda, Takatoshi, Nakagawa, Francisco Javier, Martin-Romero, and Michio, Asahi
- Subjects
inorganic chemicals ,HEK293 Cells ,Acylation ,Gene Knockdown Techniques ,Serine ,Humans ,Glycobiology and Extracellular Matrices ,Calcium ,Calcium Signaling ,Stromal Interaction Molecule 1 ,Phosphorylation ,Neoplasm Proteins - Abstract
Stromal interaction molecule 1 (STIM1) plays a pivotal role in store-operated Ca(2+) entry (SOCE), an essential mechanism in cellular calcium signaling and in maintaining cellular calcium balance. Because O-GlcNAcylation plays pivotal roles in various cellular function, we examined the effect of fluctuation in STIM1 O-GlcNAcylation on SOCE activity. We found that both increase and decrease in STIM1 O-GlcNAcylation impaired SOCE activity. To determine the molecular basis, we established STIM1-knockout HEK293 (STIM1-KO-HEK) cells using the CRISPR/Cas9 system and transfected STIM1 WT (STIM1-KO-WT-HEK), S621A (STIM1-KO-S621A-HEK), or T626A (STIM1-KO-T626A-HEK) cells. Using these cells, we examined the possible O-GlcNAcylation sites of STIM1 to determine whether the sites were O-GlcNAcylated. Co-immunoprecipitation analysis revealed that Ser(621) and Thr(626) were O-GlcNAcylated and that Thr(626) was O-GlcNAcylated in the steady state but Ser(621) was not. The SOCE activity in STIM1-KO-S621A-HEK and STIM1-KO-T626A-HEK cells was lower than that in STIM1-KO-WT-HEK cells because of reduced phosphorylation at Ser(621). Treatment with the O-GlcNAcase inhibitor Thiamet G or O-GlcNAc transferase (OGT) transfection, which increases O-GlcNAcylation, reduced SOCE activity, whereas treatment with the OGT inhibitor ST045849 or siOGT transfection, which decreases O-GlcNAcylation, also reduced SOCE activity. Decrease in SOCE activity due to increase and decrease in O-GlcNAcylation was attributable to reduced phosphorylation at Ser(621). These data suggest that both decrease in O-GlcNAcylation at Thr(626) and increase in O-GlcNAcylation at Ser(621) in STIM1 lead to impairment of SOCE activity through decrease in Ser(621) phosphorylation. Targeting STIM1 O-GlcNAcylation could provide a promising treatment option for the related diseases, such as neurodegenerative diseases.
- Published
- 2020
37. TRKB tyrosine kinase receptor is a potential therapeutic target for poorly differentiated oral squamous cell carcinoma
- Author
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Hiroko Kuwabara, Tetsuya Terada, Ryo Kawata, Michio Asahi, Kazumasa Moriwaki, and Yusuke Ayani
- Subjects
0301 basic medicine ,TRKB ,prognostic factors ,Tropomyosin receptor kinase B ,Biology ,oral squamous cell carcinoma ,03 medical and health sciences ,stomatognathic diseases ,030104 developmental biology ,0302 clinical medicine ,Oncology ,Downregulation and upregulation ,nervous system ,Neurotrophic factors ,Cell culture ,Tumor progression ,tumor differentiation ,anti-cancer drug ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,Immunohistochemistry ,Receptor ,Neurotrophin ,Research Paper - Abstract
It has been reported that one of the neurotrophin receptors, tropomyosin receptor kinase B (TRKB), is frequently overexpressed in various tumor tissues including oral squamous cell carcinoma (OSCC), and that its upregulation promotes tumor progression in human cancers. However, the correlation between TRKB overexpression and clinicopathological characteristics is not fully elucidated. Here, we present the correlation between the expression levels of TRKB and/or its secreted ligand, brain-derived neurotrophic factor (BDNF), and clinicopathological characteristics, especially regarding tumor differentiation, tissue invasion, and disease-free survival in patients with OSCC. The results obtained through immunohistochemical analysis of human OSCC tumor specimens showed that the expression levels of TRKB and/or BDNF, were significantly higher in moderately and poorly differentiated OSCC (MD/PD-OSCC) tumor cells than in well differentiated cells (WD-OSCC). Moreover, the OSCC tumors highly expressing TRKB and/or BDNF exhibited promotion in tissue invasion and reduction in disease-free survival in the patients. In an orthotopic transplantation mouse model of human OSCC cell lines, administration of a TRKB-specific inhibitor significantly suppressed the tumor growth and invasion in PD-OSCC-derived tumor cells, but not in WD-OSCC-derived tumor cells. Moreover, the TRKB inhibitor selectively blocked BDNF-induced tumor cell proliferation and migration accompanied with the suppression of TRKB phosphorylation in PD-OSCC but not in WD-OSCC in vitro. Taken together, these data suggest that the BDNF/TRKB signaling pathway may regulate tumor progression in poorly differentiated OSCC. Expression levels of signal molecules may be an accurate prognosis marker for tumor aggressiveness, and the molecules may be an attractive target for new OSCC therapies.
- Published
- 2018
38. W9 peptide enhanced osteogenic differentiation of human adipose-derived stem cells
- Author
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Koichi Ueda, Masashi Okada, Masaaki, Kazumasa Moriwaki, Michio Asahi, and Yuki Otsuki
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Biophysics ,Peptides, Cyclic ,Biochemistry ,Bone morphogenetic protein 2 ,03 medical and health sciences ,0302 clinical medicine ,Osteogenesis ,Osteoclast ,Internal medicine ,Adipocytes ,medicine ,Humans ,Molecular Biology ,Protein kinase B ,Cells, Cultured ,Osteoblasts ,biology ,Chemistry ,Akt/PKB signaling pathway ,Stem Cells ,Mesenchymal stem cell ,Cell Differentiation ,Cell Biology ,Cell biology ,RUNX2 ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,RANKL ,030220 oncology & carcinogenesis ,biology.protein ,Stem cell - Abstract
W9 is a peptide that abrogates osteoclast differentiation via blockade of nuclear factor-κB ligand (RANKL)-RANK signaling, which activates bone formation. However, W9 stimulated osteogenesis in osteoblasts and mesenchymal stem cells. The present study demonstrated that the W9 peptide promoted osteogenic differentiation of human adipose-derived stem cells (hAdSCs) even under non-osteogenic differentiation culture conditions. W9-treated hAdSCs exhibited several osteocalcin-expressing cells and great mineralization compared to the BMP2-treated hAdSCs, which suggests that the W9 peptide had potent osteogenic potential in hAdSCs. W9 treatment also markedly enhanced the phosphorylation of p38, JNK, Erk1/2, and Akt, and BMP2 treatment only enhanced the phosphorylation of p38 and Erk1/2 in hAdSCs. hAdSCs did not express the RANKL gene, but W9 treatment upregulated Runx2, Collagen type 1A1 and TGF receptor genes and increased Akt phosphorylation. These results suggest that the W9-induced potent osteogenic induction was attributed to activation of TGF and the PI3 kinase/Akt signaling pathway in hAdSCs.
- Published
- 2018
39. Recapitulating fabry disease with human induced pluripotent stem cells and CRISPR interference reveals a signaling axis involved in cardiac phenotypes
- Author
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Shigeo Wakabayashi, Kiichiro Tomoda, Michio Asahi, and Hirofumi Morihara
- Subjects
CRISPR interference ,Applied Mathematics ,General Mathematics ,medicine ,Human Induced Pluripotent Stem Cells ,Biology ,medicine.disease ,Phenotype ,Fabry disease ,Cell biology - Published
- 2018
40. Elevated O-GlcNAcylation in the tumor microenvironment promotes B16 melanoma cell progression through the suppression of p38 MAPK
- Author
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Kazumasa Moriwaki and Michio Asahi
- Subjects
O glcnacylation ,Tumor microenvironment ,medicine.anatomical_structure ,Chemistry ,Applied Mathematics ,General Mathematics ,p38 mitogen-activated protein kinases ,Cell ,Cancer research ,medicine ,B16 melanoma - Published
- 2018
41. Molecular Dissections of the DNA Repair-Deficiency Disorders Using Induced Pluripotent Stem Cells and CRISPR Interference
- Author
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Hirofumi Morihara, Kiichiro Tomoda, Marina Watanabe, and Michio Asahi
- Subjects
CRISPR interference ,Applied Mathematics ,General Mathematics ,Biology ,Induced pluripotent stem cell ,Defective DNA repair ,Cell biology - Published
- 2018
42. Augmented O-GlcNAcylation alleviates inflammation-mediated colon carcinogenesis via suppression of acute inflammation
- Author
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Michio Asahi, Yoshimasa Hirata, Kazuhide Higuchi, Eiko Koubayashi, Toshihisa Takeuchi, Kazumasa Moriwaki, Takuya Inoue, Takatoshi Nakagawa, and Kazuki Kakimoto
- Subjects
0301 basic medicine ,Nutrition and Dietetics ,Chemistry ,Colorectal cancer ,Clinical Biochemistry ,Wild type ,Medicine (miscellaneous) ,Inflammation ,NF-κB ,medicine.disease ,medicine.disease_cause ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,Dextran ,030220 oncology & carcinogenesis ,medicine ,Cancer research ,Phosphorylation ,medicine.symptom ,Carcinogenesis ,Acute colitis - Abstract
Colon cancer prevalence is high worldwide. O-GlcNAcylation has been associated with tumor growth in various tissues, including the colon; however, its link to carcinogenesis is not fully understood. We investigated the association of O-GlcNAcylation with colon carcinogenesis using a 1,2-dimethylhydrazine/dextran sodium sulfate-induced colon carcinogenesis model in wild type and O-GlcNAc transferase-transgenic (Ogt-Tg) mice. The incidence of colon cancer was significantly lower in Ogt-Tg than in wild type mice. The colonic length was not shortened in Ogt-Tg mice, and NF-κB p65 phosphorylation was strongly suppressed, indicating that reduction of inflammation might be related to the alleviation of colon carcinogenesis. Dextran sodium sulfate-induced acute colitis mice were used to evaluate the effect of O-GlcNAcylation on inflammation at the maximal inflammation period. In Ogt-Tg mice, NF-κB p65 phosphorylation and interleukin-1β mRNA expression were suppressed. Histochemical staining demonstrated shedding of colon epithelial cells in wild type mice a few days after dextran sodium sulfate treatment, whereas they remained essentially intact in Ogt-Tg mice. There were no significant differences on histochemical staining in the remaining epithelia between groups. These data suggest that O-GlcNAcylation could prevent colon carcinogenesis through reducing acute maximum inflammation, suggesting modulation of O-GlcNAcylation as a novel therapeutic option.
- Published
- 2018
43. Augmented O‐GlcNAcylation of AMP‐activated kinase promotes the proliferation of LoVo cells, a colon cancer cell line
- Author
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Yoshinobu Matsumori, Emi Ishimura, Takatoshi Nakagawa, Michio Asahi, Kazumasa Moriwaki, and Seiichi Hirano
- Subjects
0301 basic medicine ,Cancer Research ,Acylation ,Mice, Nude ,AMP-Activated Protein Kinases ,N-Acetylglucosaminyltransferases ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Downregulation and upregulation ,Cell, Molecular, and Stem Cell Biology ,In vivo ,Cell Line, Tumor ,Animals ,Humans ,PI3K/AKT/mTOR pathway ,Cell Proliferation ,Mice, Inbred BALB C ,Chemistry ,Kinase ,AMP‐activated kinase ,AMPK ,O‐GlcNAcylation ,General Medicine ,Original Articles ,In vitro ,Cell biology ,030104 developmental biology ,tumor growth ,Oncology ,colon cancer ,Cell culture ,030220 oncology & carcinogenesis ,Colonic Neoplasms ,mTOR ,Phosphorylation ,Heterografts ,Original Article ,Protein Processing, Post-Translational - Abstract
Increasing incidence of various cancers has been reported in diabetic patients. O-linked N-acetylglucosamine (O-GlcNAc) modification of proteins at serine/threonine residues (O-GlcNAcylation) is an essential post-translational modification that is upregulated in diabetic patients and has been implicated in tumor growth. However, the mechanisms by which O-GlcNAcylation promotes tumor growth remain unclear. Given that AMP-activated kinase (AMPK) has been thought to play important roles in suppressing tumor growth, we evaluated the involvement of AMPK O-GlcNAcylation on the growth of LoVo cells, a human colon cancer cell line. Results revealed that treatment with Thiamet G (TMG), an inhibitor of O-GlcNAc hydrolase, increased both anchorage-dependent and -independent growth of the cells. O-GlcNAc transferase overexpression also increased the growth. These treatments increased AMPK O-GlcNAcylation in a dose-dependent manner, which led to reduced AMPK phosphorylation and mTOR activation. Chemical inhibition or activation of AMPK led to increased or decreased growth, respectively, which was consistent with the data with genetic inhibition of AMPK. In addition, TMG-mediated acceleration of tumor growth was abolished by both chemical and genetic inhibition of AMPK. To examine the effects of AMPK O-GlcNAcylation in vivo, the LoVo cells were s.c. transplanted onto the backs of BALB/c-nu/nu mice. Injection of TMG promoted the growth and enhanced O-GlcNAcylation of the tumors of the mice. Consistent with in vitro data, AMPK O-GlcNAcylation was increased, which reduced AMPK phosphorylation and resulted in activation of mTOR. Collectively, the higher colon cancer risk of diabetic patients could be due to O-GlcNAcylation-mediated AMPK inactivation and subsequent activation of mTOR.
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- 2017
44. Interleukin-18 gene deletion protects against sepsis-induced cardiac dysfunction by inhibiting PP2A activity
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Akiyo Eguchi, Toshihiro Iwasaku, Toshiaki Mano, Yoshitaka Okuhara, Haruki Okamura, Tohru Masuyama, Shinichi Hirotani, Koichi Nishimura, Yoshiro Naito, Makiko Oboshi, Wen Li, Shunichi Yokoe, and Michio Asahi
- Subjects
0301 basic medicine ,Cardiotoxicity ,medicine.medical_specialty ,business.industry ,Phosphatase ,Protein phosphatase 2 ,030204 cardiovascular system & hematology ,Phospholamban ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Endocrinology ,Internal medicine ,Medicine ,Myocyte ,Phosphorylation ,Interleukin 18 ,Cardiology and Cardiovascular Medicine ,business ,Protein kinase B - Abstract
Background Interleukin-18 (IL-18) neutralization protects against lipopolysaccharide (LPS)-induced injuries, including myocardial dysfunction. However, the mechanism is yet to be fully elucidated. The aim of the present study was to determine whether IL-18 gene deletion prevents sepsis-induced cardiac dysfunction and to elucidate the potential mechanisms underlying IL-18-mediated cardiotoxicity by LPS. Methods and results Ten-week-old male wild-type (WT) and IL-18 knockout (IL-18 KO) mice were intraperitoneally administered LPS. Serial echocardiography showed better systolic pump function and less left ventricular (LV) dilatation in LPS-treated IL-18 KO mice compared with those in LPS-treated WT mice. LPS treatment significantly decreased the levels of phospholamban (PLN) and Akt phosphorylation in WT mice compared with those in saline-treated WT mice, while the LPS-induced decrease in the phosphorylation levels was attenuated in IL-18 KO mice compared with that in WT mice. IL-18 gene deletion also attenuated an LPS-induced increase of type 2 protein phosphatase 2A (PP2A) activity, a molecule that dephosphorylates PLN and Akt. There was no difference in type 1 protein phosphatase (PP1) activity. To address whether IL-18 affects PLN and Akt phosphorylation via PP2A activation in cardiomyocytes, rat neonatal cardiac myocytes were cultured and stimulated using 100ng/ml of recombinant rat IL-18. Exogenous IL-18 decreased the level of PLN and Akt phosphorylation in cardiomyocytes. PP2A activity but not PP1 activity was increased by IL-18 stimulation in cardiomyocytes. Conclusions IL-18 plays a pivotal role in advancing sepsis-induced cardiac dysfunction, and the mechanisms underlying IL-18-mediated cardiotoxicity potentially involve the regulation of PLN and Akt phosphorylation through PP2A activity.
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- 2017
45. Augmented TME O-GlcNAcylation Promotes Tumor Proliferation through the Inhibition of p38 MAPK
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Michio Asahi and Kazumasa Moriwaki
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0301 basic medicine ,Cancer Research ,Tumor microenvironment ,Cell signaling ,medicine.medical_treatment ,Cancer ,Biology ,medicine.disease ,Proinflammatory cytokine ,Metastasis ,03 medical and health sciences ,030104 developmental biology ,Cytokine ,Oncology ,Downregulation and upregulation ,Tumor progression ,Cancer research ,medicine ,Molecular Biology - Abstract
O-GlcNAcylation is a dynamic O-linked glycosylation event that plays a crucial role in regulating cellular signaling. Recent studies indicate that increased O-GlcNAcylation is a general feature in cancer and contributes to various cancer phenotypes, including cell proliferation, survival, invasion, metastasis, and energy metabolism. However, the role of O-GlcNAcylation in the tumor microenvironment (TME) is not fully elucidated. Here, B16 melanoma cells were subcutaneously transplanted into O-GlcNAc transferase transgenic (Ogt-Tg) mice exhibiting elevated O-GlcNAcylation to examine the effect of O-GlcNAcylation in the TME on tumor progression. In this model system, B16 tumor growth was significantly higher in Ogt-Tg/+ mice compared with wild-type (WT) mice. The tumors grown in Ogt-Tg/+ mice showed significant downregulation of p38 MAPK activity and upregulation of the ERK1/2 signaling pathway. In addition, proinflammatory cytokine production was significantly lower in the tumor tissues from Ogt-Tg/+ mice than in those from WT mice. Activation of NF-κB, a key regulator in the cytokine production, was downregulated in the macrophages of the tumor tissues grown in Ogt-Tg/+ mice. These data reveal that elevated O-GlcNAcylation in the TME reduces the production of inflammatory cytokines and promotes cancer progression through downregulation of p38 MAPK activity and subsequent upregulation of the ERK1/2 signaling pathway. Implications: The reduced production of inflammatory cytokines by augmented O-GlcNAcylation in the TME, mainly macrophages, promotes tumor proliferation through the inhibition of p38 MAPK and suggests a possible cause of increased morbidity and mortality rates for various cancers in diabetic patients. Mol Cancer Res; 15(9); 1287–98. ©2017 AACR.
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- 2017
46. Caveolae-specific activation loop between CaMKII and L-type Ca2+channel aggravates cardiac hypertrophy in α1-adrenergic stimulation
- Author
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Kazumasa Moriwaki, Yasushi Fujio, Shota Tanaka, Nao Hayamizu, Sachi Matsunami, Kota Tonegawa, Hiroyuki Nakayama, Masanori Obana, Makiko Maeda, Shohei Kumagai, Hiroshi Kiyonari, Wataru Otsuka, and Michio Asahi
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0301 basic medicine ,medicine.medical_specialty ,Physiology ,Biology ,03 medical and health sciences ,030104 developmental biology ,Endocrinology ,Adrenergic stimulation ,Activation loop ,Physiology (medical) ,Caveolae ,Cardiac hypertrophy ,Ca2+/calmodulin-dependent protein kinase ,Internal medicine ,cardiovascular system ,medicine ,Ca2 channels ,L-type calcium channel ,Cardiology and Cardiovascular Medicine - Abstract
Activation of CaMKII induces a myriad of biological processes and plays dominant roles in cardiac hypertrophy. Caveolar microdomain contains many calcium/calmodulin-dependent kinase II (CaMKII) targets, including L-type Ca2+channel (LTCC) complex, and serves as a signaling platform. The location of CaMKII activation is thought to be critical; however, the roles of CaMKII in caveolae are still elusive due to lack of methodology for the assessment of caveolae-specific activation. Our aim was to develop a novel tool for the specific analysis of CaMKII activation in caveolae and to determine the functional role of caveolar CaMKII in cardiac hypertrophy. To assess the caveolae-specific activation of CaMKII, we generated a fusion protein composed of phospholamban and caveolin-3 (cPLN-Cav3) and GFP fusion protein with caveolin-binding domain fused to CaMKII inhibitory peptide (CBD-GFP-AIP), which inhibits CaMKII activation specifically in caveolae. Caveolae-specific activation of CaMKII was detected using phosphospecific antibody for PLN (Thr17). Furthermore, adenoviral overexpression of LTCC β2a-subunit (β2a) in NRCMs showed its constitutive phosphorylation by CaMKII, which induces hypertrophy, and that both phosphorylation and hypertrophy are abolished by CBD-GFP-AIP expression, indicating that β2aphosphorylation occurs specifically in caveolae. Finally, β2aphosphorylation was observed after phenylephrine stimulation in β2a-overexpressing mice, and attenuation of cardiac hypertrophy after chronic phenylephrine stimulation was observed in nonphosphorylated mutant of β2a-overexpressing mice. We developed novel tools for the evaluation and inhibition of caveolae-specific activation of CaMKII. We demonstrated that phosphorylated β2adominantly localizes to caveolae and induces cardiac hypertrophy after α1-adrenergic stimulation in mice.NEW & NOTEWORTHY While signaling in caveolae is thought to be important in cardiac hypertrophy, direct evidence is missing due to lack of tools to assess caveolae-specific signaling. This is the first study to demonstrate caveolae-specific activation of CaMKII signaling in cardiac hypertrophy induced by α1-adrenergic stimulation using an originally developed tool.
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- 2017
47. Bone Marrow-Derived Endothelial Progenitor Cells Reduce Recurrent Miscarriage in Gestation
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Michio Asahi, Kazuyoshi Kanki, Yoshito Terai, Masaaki, and Masahide Ohmichi
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Male ,0301 basic medicine ,Abortion, Habitual ,medicine.medical_specialty ,Cell Survival ,Angiogenesis ,Placenta ,Biomedical Engineering ,lcsh:Medicine ,Antigens, CD34 ,Bone Marrow Cells ,Preeclampsia ,Miscarriage ,Andrology ,Neovascularization ,Mice ,03 medical and health sciences ,Cell Movement ,Pregnancy ,Recurrent miscarriage ,medicine ,Animals ,Progenitor cell ,Cells, Cultured ,Cell Proliferation ,Endothelial Progenitor Cells ,Gynecology ,Transplantation ,Vascular Endothelial Growth Factor Receptor-1 ,Reverse Transcriptase Polymerase Chain Reaction ,business.industry ,lcsh:R ,Cell Biology ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,embryonic structures ,cardiovascular system ,Female ,Bone marrow ,medicine.symptom ,business ,circulatory and respiratory physiology - Abstract
Bone marrow-derived endothelial progenitor cells (EPCs) have been shown to contribute to not only angiogenesis in ischemic tissue but also neovascularization in uterine endometrium formation. Reduced neovascularization and elevation of serum soluble Flt1, a functional blockage of VEGF, in the development of placenta is thought to be one of the major causes of repeated miscarriages in gestation. We then examined whether transfusion of VEGF-expressing extrinsic EPCs prevented frequent miscarriage via its promotional effect on neovascularization with a VEGF–eNOS signaling pathway in a mouse miscarriage model. The results showed that systemic EPC transfusion significantly reduced the rate of miscarriage, and EPCs were frequently observed in the miscarriage placenta. In contrast, only a few EPCs were detected in the placenta of normal gestation. The vascular pattern was irregular, and vessel size was small in the miscarriage placenta compared with that of normal gestation. The placental vascular pattern in miscarriage tended to be normalized with increased vessel size up to a similar level as normal gestation by EPC recruitment. For the mechanistic insight, since soluble Flt1 inhibits EPC functions, it was suggested that the increased soluble Flt1 could suppress the recruited EPC functional activity in the miscarriage placenta. In vitro experiments by soluble Flt1 treatment in cultured EPCs suggested that the vascular abnormality could be partly due to the inhibition of eNOS expression by the increased amounts of soluble Flt1. These findings from animal experiments indicated that autologous EPC therapy may be a novel therapy to prevent miscarriage in high-risk pregnancies, such as preeclampsia.
- Published
- 2016
48. Enhancement of
- Author
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Yutaka, Naka, Toshihiko, Okada, Takatoshi, Nakagawa, Eiko, Kobayashi, Yuka, Kawasaki, Yasuyoshi, Tanaka, Hideki, Tawa, Yuki, Hirata, Ken, Kawakami, Kazuki, Kakimoto, Takuya, Inoue, Toshihisa, Takeuchi, Shinya, Fukunishi, Yoshinobu, Hirose, Kazuhisa, Uchiyama, Michio, Asahi, and Kazuhide, Higuchi
- Subjects
O-GlcNAcylation ,endocrine system diseases ,type 2 diabetes mellitus ,SNAIL ,nutritional and metabolic diseases ,colorectal cancer ,Articles ,β-catenin - Abstract
Reversible post-translational modification of serine and threonine residues by O-linked N-acetylglucosamine (O-GlcNAc), termed O-GlcNAcylation has been indicated to regulate the activities of a number of different proteins. Augmented O-GlcNAcylation contributes to the etiologies of type 2 diabetes mellitus (T2DM) and cancer. Moreover, diabetic conditions increase the risk of colorectal cancer. However, the effect of O-GlcNAcylation in patients with colorectal cancer and concurrent T2DM has not been elucidated. The current study evaluated the level of O-GlcNAcylation in patients with colorectal cancer with or without T2DM. Notably, O-GlcNAcylation levels were significantly higher in tissues from patients with T2DM compared with those in patients without T2DM, and higher in cancer tissues compared with corresponding adjacent tissues. O-GlcNAcylation and cancer stage were more strongly correlated in cancer tissues from patients with T2DM compared with those from patients without T2DM. Additionally, distant metastasis was significantly correlated with O-GlcNAcylation in cancer tissues from patients with T2DM. β-catenin levels in colorectal cancer tissues were the highest in patients with advanced-stage cancer and concurrent T2DM. In SW480 human colon cancer cells, thiamet G (TMG) treatment and OGA silencing, which increased O-GlcNAcylation, significantly increased β-catenin and SNAIL in high-glucose, but not during normal-glucose conditions. These data suggest that O-GlcNAcylation is closely associated with distant metastasis, most likely through upregulation of the β-catenin/SNAIL signaling pathway in colorectal cancer patients with T2DM.
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- 2019
49. Overexpression of Na
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Shigeo, Wakabayashi, Hirofumi, Morihara, Shunichi, Yokoe, Takatoshi, Nakagawa, Kazumasa, Moriwaki, Kiichiro, Tomoda, and Michio, Asahi
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rho-Associated Kinases ,Sodium-Hydrogen Exchanger 1 ,Cell Death ,Cell Survival ,Pyridines ,Cell Membrane ,Endoderm ,Induced Pluripotent Stem Cells ,Cell Differentiation ,Cell Biology ,Hydrogen-Ion Concentration ,Amides ,Gene Expression Regulation, Enzymologic ,Mesoderm ,Methylamines ,Necrosis ,Cytosol ,Humans ,Phosphorylation - Abstract
Understanding the specific properties of human induced pluripotent stem cells (iPSCs) is important for quality control of iPSCs. Having incidentally discovered that overexpression of plasma membrane Na(+)/H(+) exchanger 1 (NHE1) induces cell death in iPSCs, we investigated the mechanism of NHE1-induced cell death. Doxycycline-induced NHE1 overexpression arrested cell growth, and nearly all cells were killed by a necrotic process within 72 h. NHE1 overexpression led to sustained activation of Rho-associated coiled-coil kinase (ROCK), accompanied by dramatic changes in cell shape, cell elongation, and swelling of peripheral cells in iPSC colonies, as well as marked stress fiber formation. The ROCK inhibitor Y27632 reduced NHE1-induced cell death. ROCK-dependent phenotypes were suppressed by a loss-of-function mutation of NHE1 and inhibited by an inhibitor of NHE1 activity, indicating that NHE1-mediated transport activity is required. Moreover, ROCK was activated by trimethylamine treatment–mediated cytosolic alkalinization and accumulated in the plasma membrane near NHE1 in peripheral iPSCs of cell colonies. By contrast, cell death did not occur in mesendoderm-like cells that had differentiated from iPSCs, indicating that the NHE1-mediated effects were specific for iPSCs. These results suggest that NHE1 overexpression specifically induces death of iPSCs via sustained ROCK activation, probably caused by an increase in local pH near NHE1. Finally, monensin, a Na(+)/H(+) exchange ionophore, selectively killed iPSCs, suggesting that monensin could help eliminate iPSCs that remain after differentiation, a strategy that might be useful for improving regenerative medicine.
- Published
- 2019
50. Augmented O-GlcNAcylation attenuates intermittent hypoxia-induced cardiac remodeling through the suppression of NFAT and NF-κB activities in mice
- Author
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Takatoshi, Nakagawa, Yuichi, Furukawa, Tetsuya, Hayashi, Atsuo, Nomura, Shunichi, Yokoe, Kazumasa, Moriwaki, Ryuji, Kato, Yoshio, Ijiri, Takehiro, Yamaguchi, Yasukatsu, Izumi, Minoru, Yoshiyama, and Michio, Asahi
- Subjects
Glycogen Synthase Kinase 3 beta ,NFATC Transcription Factors ,Ventricular Remodeling ,Acylation ,Myocardium ,NF-kappa B ,Mice, Transgenic ,N-Acetylglucosaminyltransferases ,Cell Line ,Mice ,Oxidative Stress ,HEK293 Cells ,Diabetes Mellitus, Type 2 ,Echocardiography ,Animals ,Humans ,Phosphorylation ,Hypoxia - Abstract
Type 2 diabetes mellitus (T
- Published
- 2019
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