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論文
Cui, Hong ; Okamoto, Yasuo ; Yoshioka, Kazuaki ; Du, Wa ; Takuwa, Noriko ; Zhang, Wei ; Asano, Masahide ; Shibamoto, Toshishige ; Takuwa, Yoh
出版情報: Journal of Allergy and Clinical Immunology.  132  pp.1205-1214,  2013-11-01.  Elsevier
URL: http://hdl.handle.net/2297/36259
概要: Background Sphingosine-1-phosphate receptor 2 (S1P2) is expressed in vascular endothelial cells (ECs). However, the role of S1P 2 in vascular barrier integrity and anaphylaxis is not well understood. Endothelial nitric oxide synthase (eNOS) generates nitric oxide to mediate vascular leakage, compromising survival in patients with anaphylaxis. We recently observed that endothelial S1P2 inhibits Akt, an activating kinase of eNOS. Objective We tested the hypothesis that endothelial S1P 2 might suppress eNOS, exerting a protective effect against endothelial barrier disruption and anaphylaxis. Methods Mice deficient in S1P2 and eNOS underwent antigen challenge or platelet-activating factor (PAF) injection. Analyses were performed to examine vascular permeability and the underlying mechanisms. Results S1pr2 deletion augmented vascular leakage and lethality after either antigen challenge or PAF injection. PAF injection induced activation of Akt and eNOS in the aortas and lungs of S1pr2-null mice, which were augmented compared with values seen in wild-type mice. Consistently, PAF-induced increase in cyclic guanosine monophosphate levels in the aorta was enhanced in S1pr-null mice. Genetic Nos3 deletion or pharmacologic eNOS blockade protected S1pr2-null mice from aggravation of barrier disruption after antigen challenge and PAF injection. ECs isolated from S1pr2-null mice exhibited greater stimulation of Akt and eNOS, with enhanced nitric oxide production in response to sphingosine-1-phosphate or PAF, compared with that seen in wild-type ECs. Moreover, S1pr2-deficient ECs showed more severe disassembly of adherens junctions with augmented S-nitrosylation of β-catenin in response to PAF, which was restored by pharmacologic eNOS blockade. Conclusion S1P2 diminishes harmful robust eNOS stimulation and thereby attenuates vascular barrier disruption, suggesting potential usefulness of S1P2 agonists as novel therapeutic agents for anaphylaxis. © 2013 American Academy of Allergy, Asthma & Immunology. 続きを見る
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Qia, Xun ; Okamoto, Yasuo ; Murakawa, Tomomi ; Wang, Fei ; Oyama, Osamu ; Ohkawa, Ryunosuke ; Yoshioka, Kazuaki ; Du, Wa ; Sugimoto, Naotoshi ; Yatomi, Yutaka ; Takuwa, Noriko ; Takuwa, Yoh
出版情報: European Journal of Pharmacology.  634  pp.121-131,  2010-05-01.  Elsevier BV
URL: http://hdl.handle.net/2297/23922
概要: 金沢大学医薬保健研究域医学系<br />Therapeutic angiogenesis is a promising strategy for treating ischemia. The lysophospholipid m ediator sphingosine-1-phosphate (S1P) acts on vascular endothelial cells to stimulate migration and tube formation, and plays the critical role in developmental angiogenesis. We developed poly(lactic-co-glycolic-acid) (PLGA)-based S1P-containing microparticles (PLGA-S1P), which are biodegradable and continuously release S1P, and studied the effects of PLGA-S1P on neovascularization in murine ischemic hindlimbs. Intramuscular injections of PLGA-S1P stimulated blood flow in C57BL/6 mice dose-dependently, with repeated administrations at a 3-day interval, rather than a single bolus or 6-day interval, over 28. days conferring the optimal stimulating effect. In Balb/c mice that exhibit limb necrosis and dysfunction due to retarded blood flow recovery, injections of PLGA-S1P stimulated blood flow with alleviation of limb necrosis and dysfunction. PLGA-S1P alone did not induce edema in ischemic limbs, and rather blocked vascular endothelial growth factor-induced edema. PLGA-S1P not only increased the microvessel densities in ischemic muscle, but promoted coverage of vessels with smooth muscle cells and pericytes, thus stabilizing vessels. PLGA-S1P stimulated Akt and ERK with increased phosphorylation of endothelial nitric oxide synthase in ischemic muscle. The effects of the nitric oxide synthase inhibitor, Nω-nitro-l-arginine methylester, showed that PLGA-S1P-induced blood flow stimulation was partially dependent on nitric oxide. Injections of PLGA-S1P also increased the expression of angiogenic factors and the recruitment of CD45-, CD11b- and Gr-1-positive myeloid cells, which are implicated in post-ischemic angiogenesis, into ischemic muscle. These results indicate that PLGA-based, sustained local delivery of S1P is a potentially useful therapeutic modality for stimulating post-ischemic angiogenesis. © 2010 Elsevier B.V. 続きを見る
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Takuwa, Yoh ; Okamoto, Yasuo ; Yoshioka, Kazuaki ; Takuwa, Noriko
出版情報: BBA - Molecular and Cell Biology of Lipids.  781  pp.483-488,  2008-09-01.  Elsevier
URL: http://hdl.handle.net/2297/11734
概要: 金沢大学医薬保健研究域医学系<br />The plasma lysophospholipid mediator sphingosine-1-phosphate (S1P) is produced exclusively by sphingosine kinase (SPHK) 1 and SPHK2 in vivo, and plays diverse biological and pathophysiological roles by acting largely through three members of the G protein-coupled S1P receptors, S1P1, S1P2 and S1P3. S1P1 expressed on endothelial cells mediates embryonic vascular maturation and maintains vascular integrity by contributing to eNOS activation, inhibiting vascular permeability and inducing endothelial cell chemotaxis via Gi-coupled mechanisms. By contrast, S1P2, is expressed in high levels on vascular smooth muscle cells (VSMCs) and certain types of tumor cells, inhibiting Rac and cell migration via a G12/13-and Rho-dependent mechanism. In rat neointimal VSMCs, S1P1 is upregulated to mediate local production of platelet-derived growth factor, which is a key player in vascular remodeling. S1P3 expressed on endothelial cells also mediates chemotaxis toward S1P and vasorelaxation via NO production in certain vascular bed, playing protective roles for vascular integrity. S1P3 expressed on VSMCs and cardiac sinoatrial node cells mediates vasopressor and negative chronotropic effect, respectively. In addition, S1P3, together with S1P2 and SPHK1, is suggested to play a protective role against acute myocardial ischemia. However, our recent work indicates that overexpressed SPHK1 is involved in cardiomyocyte degeneration and fibrosis in vivo, in part through S1P activation of the S1P3 signaling. We also demonstrated that exogenously administered S1P accelerates neovascularization and blood flow recovery in ischemic limbs, suggesting its usefulness for angiogenic therapy. These results provide evidence for S1P receptor subtype-specific pharmacological intervention as a novel therapeutic approach to cardiovascular diseases and cancer. © 2008 Elsevier B.V. All rights reserved. 続きを見る
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Du, Wa ; Takuwa, Noriko ; Yoshioka, Kazuaki ; Okamoto, Yasuo ; Gonda, Koichi ; Sugihara, Kazushi ; Fukamizu, Akiyoshi ; Asano, Masahide ; Takuwa, Yoh
出版情報: Cancer Research.  70  pp.772-781,  2010-01-15.  American Association for Cancer Research
URL: http://hdl.handle.net/2297/21765
概要: 金沢大学医薬保健研究域医学系<br />Sphingosine-1-phosphate (S1P) has been implicated in tumor angiogenesis by acting through the Gi-coupled chemotactic receptor S1P1. Here, we report that the distinct receptor S1P2 is responsible for mediating the G12/13/Rho-dependent inhibitory effects of S1P on Akt, Rac, and cell migration, thereby negatively regulating tumor angiogenesis and tumor growth. By using S1P2LacZ/+ mice, we found that S1P2 was expressed in both tumor and normal blood vessels in many organs, in both endothelial cells (EC) and vascular smooth muscle cells, as well as in tumor-associated, CD11b-positive bone marrow-derived cells (BMDC). Lewis lung carcinoma or B16 melanoma cells implanted in S1P2-deficient (S1P2-/-) mice displayed accelerated tumor growth and angiogenesis with enhanced association of vascular smooth muscle cells and pericytes. S1P2-/- ECs exhibited enhanced Rac activity, Akt phosphorylation, cell migration, proliferation, and tube formation in vitro. Coinjection of S1P2-/- ECs and tumor cells into wild-type mice also produced a relative enhancement of tumor growth and angiogenesis in vivo. S1P2-/- mice were also more efficient at recruiting CD11b-positive BMDCs into tumors compared with wild-type siblings. Bone marrow chimera experiments revealed that S1P2 acted in BMDCs to promote tumor growth and angiogenesis. Our results indicate that, in contrast to endothelial S1P1, which stimulates tumor angiogenesis, S1P 2 on ECs and BMDCs mediates a potent inhibition of tumor angiogenesis, suggesting a novel therapeutic tactic for anticancer treatment. ©2010 AACR. 続きを見る
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Wang, Fei ; Okamoto, Yasuo ; Inoki, Isao ; Yoshioka, Kazuaki ; Du, Wa ; Qi, Xun ; Takuwa, Noriko ; Gonda, Koichi ; Yamamoto, Yasuhiko ; Ohkawa, Ryunosuke ; Nishiuchi, Takumi ; Sugimoto, Naotoshi ; Yatomi, Yutaka ; Mitsumori, Kunitoshi ; Asano, Masahide ; Kinoshita, Makoto ; Takuwa, Yoh
出版情報: The journal of clinical investigation.  120  pp.3979-3995,  2010-11-01.  American Society for Clinical Investigation
URL: http://hdl.handle.net/2297/25352
概要: 金沢大学医薬保健研究域医学系<br />Sphingosine-1-phosphate (S1P) is a biologically active sphingolipid that has pleiotropic effec ts in a variety of cell types including ECs, SMCs, and macrophages, all of which are central to the development of atherosclerosis. It may therefore exert stimulatory and inhibitory effects on atherosclerosis. Here, we investigated the role of the S1P receptor S1PR2 in atherosclerosis by analyzing S1pr2–/– mice with an Apoe–/– background. S1PR2 was expressed in macrophages, ECs, and SMCs in atherosclerotic aortas. In S1pr2–/–Apoe–/– mice fed a high-cholesterol diet for 4 months, the area of the atherosclerotic plaque was markedly decreased, with reduced macrophage density, increased SMC density, increased eNOS phosphorylation, and downregulation of proinflammatory cytokines compared with S1pr2+/+Apoe–/– mice. Bone marrow chimera experiments indicated a major role for macrophage S1PR2 in atherogenesis. S1pr2–/–Apoe–/– macrophages showed diminished Rho/Rho kinase/NF-κB (ROCK/NF-κB) activity. Consequently, they also displayed reduced cytokine expression, reduced oxidized LDL uptake, and stimulated cholesterol efflux associated with decreased scavenger receptor expression and increased cholesterol efflux transporter expression. S1pr2–/–Apoe–/– ECs also showed reduced ROCK and NF-κB activities, with decreased MCP-1 expression and elevated eNOS phosphorylation. Pharmacologic S1PR2 blockade in S1pr2+/+Apoe–/– mice diminished the atherosclerotic plaque area in aortas and modified LDL accumulation in macrophages. We conclude therefore that S1PR2 plays a critical role in atherogenesis and may serve as a novel therapeutic target for atherosclerosis. 続きを見る
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論文
Tanahashi, Hiroshi ; Yoshioka, Kazuaki
出版情報: Neuroscience Letters.  439  pp.293-297,  2008-07-18.  Elsevier
URL: http://hdl.handle.net/2297/10014
概要: 金沢大学医薬保健研究域医学系<br />In a previous study, we reported that Alzheimer's disease-associated presenilin-2 interac ts with a LIM-domain protein, namely, DRAL/FHL2/SLIM3. In this study, we investigated whether DRAL modifies the metabolism of the amyloid precursor protein (APP). We used small interfering RNA (siRNA) to knockdown DRAL in COS7 and HEK293 cells that stably overexpress APP695. We found that the knockdown was accompanied by a decrease in the amount of secreted α-secretase-cleaved APP and the membrane-bound C-terminal fragment C83 and an increase in the amount of secreted β-amyloid peptide (Aβ) from the cells. We also found that in addition to a disintegrin and metalloprotease (ADAM)-17, DRAL binds to ADAM-10. Thus, DRAL may be involved in the processing of APP through the α-secretase pathway. © 2008 Elsevier Ireland Ltd. All rights reserved. 続きを見る
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論文
吉岡, 和晃 ; Yoshioka, Kazuaki
出版情報: 平成28(2016)年度 科学研究費補助金 基盤研究(C) 研究成果報告書 = 2016 Fiscal Year Final Research Report.  2014-04-01 - 2017-03-31  pp.5p.-,  2017-05-26. 
URL: http://hdl.handle.net/2297/00050990
概要: 金沢大学医薬保健研究域医学系<br />当研究室では、クラスII型PI3K-C2α KO マウスは胎生期の血管形成不全により胎生致死となり、C2αが胎生期血管形成及び生後の血管恒常性維持に必要であることを 見いだしていた。本研究では、内皮におけるPI(3)Pレベル調節機構を解析するために、PI(3)P脂質脱リン酸化酵素(MTM)種を同定した。更にMTM-KOマウスを作出して表現型を解析した結果、ホモKOは出生直後24時間以内に全例死亡することを見出した。以上の結果から、内皮における脂質リン酸化酵素C2aと脱リン酸化酵素MTMは強調して働き、膜小胞上でPI(3)Pレベルを調節することによって、内皮の恒常性を維持していることが示唆された。<br />Phosphatidylinositol 3-kinases (PI3Ks) are the family of lipid kinases responsible for the generation of 3’-phosphoinositides. We have recently reported that class II a-isoform PI3K (C2a) plays a crucial role in developmental and pathological angiogenesis, and is indispensable for the maintenance of the VE-cadherin-mediated EC barrier function and receptor endocytosis. These defects result in impaired vascular homeostasis under the pathophysiological conditions. In this study, we found that among myotubularin-related protein (MTMR) family members, the expression of MTMRx is relatively abundant in ECs. We found that, in HUVECs, MTMRx was localized mainly in the endosomes. Next we analyzed the phenotype of MTMRx global KO mice. MTMRx mice showed normally development but die perinatally. We conclude that C2a regulates vascular homeostasis through controlling PI(3)P+-membrane trafficking, cooperating with MTMRx in ECs.<br />研究課題/領域番号:26460292, 研究期間(年度):2014-04-01 - 2017-03-31 続きを見る
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論文
吉岡, 和晃 ; Yoshioka, Kazuaki
出版情報: 平成25(2013)年度 科学研究費補助金 基盤研究(C) 研究成果報告書 = 2013 Fiscal Year Final Research Report.  2011-2013  pp.6p.-,  2014-05-20.  金沢大学医薬保健研究域医学系
URL: http://hdl.handle.net/2297/00050991
概要: 金沢大学医薬保健研究域医学系<br />本研究において申請者らは、発生期・生後の生理的および病的(虚血、腫瘍)血管新生ならびに血管恒常性維持にクラスII型PI3K-C2αが重要な役割を果たすことを明らかにした。内皮細 胞においてC2αをノックダウンすると、エンドソーム輸送の障害、VE-カドヘリンの配送異常が引き起こされた。C2αヘテロ欠損マウスでは、アンジオテンシンII投与に対する解離性大動脈瘤形成の発症率上昇が見られた。以上のことから、C2αは血管内皮細胞において、小胞輸送の制御を介した物質輸送及びエンドソーム上でのシグナル伝達に必須であり、これらの作用により血管形成と血管の健全性維持に重要な役割を担うことが明らかになった。<br />Although class I PI3Ks and class III Vps34 are well-characterized, the physiological roles of PI3K class IIa (C2a) remain largely unknown. Global C2a-null mice and EC-specific C2a conditional KO mice showed embryonic lethality due to defects in sprouting angiogenesis and vascular maturation. In cultured ECs, siRNA-mediated knockdown of C2a resulted in impaired endosomal trafficking. C2a knockdown also impaired cell signaling including VEGF receptor-2 internalization and RhoA activation on endosomes, but not Akt and ERK. Consequently, endosomal delivery of VE-cadherin to EC junctions was disturbed, leading to defects in VE-cadherin transport and assembly and barrier integrity. C2a haplo-insufficient mice exhibited defective postnatal angiogenesis and vascular barrier integrity with a higher incidence of dissecting aortic aneurysm formation on angiotensin-II infusion. Thus, C2a plays a crucial role in vascular formation and barrier integrity.<br />研究課題/領域番号:23590257, 研究期間(年度):2011-2013 続きを見る
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論文
吉岡, 和晃 ; Yoshioka, Kazuaki
出版情報: 平成22(2010)年度 科学研究費補助金 基盤研究(C) 研究成果報告書 = 2010 Fiscal Year Final Research Report.  2008-2010  pp.6p.-,  2011-05-19.  金沢大学医薬保健研究域医学系
URL: http://hdl.handle.net/2297/00050992
概要: 本研究では、"クラスII型PI3キナーゼC2α"の機能、特に血管恒常性における役割を明らかにするために、C2α遺伝子KOマウスを用いてC2αの生理機能と血管障害における役割を解析するこ とを目的として実施した。KOマウスの表現型解析から、胎生期血管形成プロセスの異常は血管新生、特に血管成熟過程に起因する可能性が高いと考えられた。また、C2αヘテロKOマウス血管障害モデルでは、解離性大動脈瘤が高頻度に観察された。C2αはこれまで全く生理機能が知られてなく、クラスI型PI3キナーゼとは異なる基質特異性、細胞内分布を示すことから、血管恒常性維持に必須の新たな機能的役割を持つ細胞内制御因子でありことが明らかとなった。<br />Phosphatidylinositol-3-OH kinase (PI3K) family, which comprises three classes, regulates a diverse array of cellular processes through the generation of 3-phosphoinositides. Although class I PI3Ks including p110α, p110β, p110δ and p110γ isoforms were well characterized among three classes, the in vivo physiological functions of class II PI3Ks, which comprise three members PI3K-C2α (C2α), C2β and C2γ, remain largely unknown. We found that Pik3c2a gene-global disruption (C2α KO) and conditional loss of C2α in endothelial cells (ECs) in mice, but not in vascular smooth muscles (VSMCs) and cardiomyocytes, caused embryonic lethality due to impairment of developmental angiogenesis characterized by incomplete EC sprouting and mural-cell (VSMCs and pericytes) coverage. Finally, C2α-haploinsufficient mice are alive, but exhibit vascular hyperpermeability and a higher incidence of dissecting aortic aneurysms with rupture on angiotensin-II (AngII) infusion. These results provide the first evidence that C2α plays a novel essential role in endothelial physiology, particularly angiogenesis and barrier integrity, through regulating endosomal trafficking and underscore broader roles for PI3K family members in vascular physiology.<br />研究課題/領域番号:20590207, 研究期間(年度):2008-2010 続きを見る
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Zhao, Juanjuan ; Okamoto, Yasuo ; Asano, Yuya ; Ishimaru, Kazuhiro ; Aki, Sho ; Yoshioka, Kazuaki ; Takuwa, Noriko ; Wada, Takashi ; Inagaki, Yutaka ; Takahashi, Chiaki ; Nishiuchi, Takumi ; Takuwa, Yoh ; 安藝, 翔 ; 吉岡, 和晃 ; 多久和, 典子 ; 和田, 隆志 ; 髙橋, 智聡 ; 西内, 巧 ; 多久和, 陽
出版情報: PLoS ONE.  13  pp.e0197604-,  2018-05-21.  Public Library of Science
URL: http://hdl.handle.net/2297/00053881
概要: 金沢大学医薬保健研究域医学系<br />Idiopathic pulmonary fibrosis is a devastating disease with poor prognosis. The pathogenic rol e of the lysophospholipid mediator sphingosine-1-phosphate and its receptor S1PR2 in lung fibrosis is unknown. We show here that genetic deletion of S1pr2 strikingly attenuated lung fibrosis induced by repeated injections of bleomycin in mice. We observed by using S1pr2 LacZ/+ mice that S1PR2 was expressed in alveolar macrophages, vascular endothelial cells and alveolar epithelial cells in the lung and that S1PR2-expressing cells accumulated in the fibrotic legions. Bone marrow chimera experiments suggested that S1PR2 in bone marrow–derived cells contributes to the development of lung fibrosis. Depletion of macrophages greatly attenuated lung fibrosis. Bleomycin administration stimulated the mRNA expression of the profibrotic cytokines IL-13 and IL-4 and the M2 markers including arginase 1, Fizz1/Retnla, Ccl17 and Ccl24 in cells collected from broncho-alveolar lavage fluids (BALF), and S1pr2 deletion markedly diminished the stimulated expression of these genes. BALF cells from bleomycin–administered wild-type mice showed a marked increase in phosphorylation of STAT6, a transcription factor which is activated downstream of IL-13, compared with saline–administered wild-type mice. Interestingly, in bleomycin–adminis-tered S1pr2 -/- mice, STAT6 phosphorylation in BALF cells was substantially diminished compared with wild-type mice. Finally, pharmacological S1PR2 blockade in S1pr2 +/+ mice alleviated bleomycin–induced lung fibrosis. Thus, S1PR2 facilitates lung fibrosis through the mechanisms involving augmentation of IL-13 expression and its signaling in BALF cells, and represents a novel target for treating lung fibrosis. © 2018 Zhao et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 続きを見る