title: G-protein coupled receptor 15 mediates angiogenesis and cytoprotective function of thrombomodulin.
abstract: Thrombomodulin (TM) stimulates angiogenesis and protects vascular endothelial cells (ECs) via its fifth epidermal growth factor-like region (TME5); however, the cell surface receptor that mediates the pro-survival signaling activated by TM has remained unknown. We applied pull-down assay followed by MALDI-TOF MS and western blot analysis, and identified G-protein coupled receptor 15 (GPR15) as a binding partner of TME5. TME5 rescued growth inhibition and apoptosis caused by calcineurin inhibitor FK506 in vascular ECs isolated from wild type (WT) C57BL/6 mice. On the other hand, TME5 failed to protect ECs isolated from GPR15 knockout (GPR15 KO) mice from FK506-caused vascular injury. TME5 induced activation of extracellular signal-regulated kinase (ERK) and increased level of anti-apoptotic proteins in a GPR15 dependent manner. In addition, in vivo Matrigel plug angiogenesis assay found that TME5 stimulated angiogenesis in mice. TME5 promoted endothelial migration in vitro. Furthermore, TME5 increased production of NO in association with activated endothelial NO synthase (eNOS) in ECs. All these pro-angiogenesis functions of TME5 were abolished by knockout of GPR15. Our findings suggest that GPR15 plays an important role in mediating cytoprotective function as well as angiogenesis of TM.
authors.affiliation: Department of Hematology and Respiratory Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan.|Department of Hematology, Fukushima Medical University, Fukushima, Japan.|Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Pan
authors.affiliation: Department of Hematology and Respiratory Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan.|Department of Hematology, Fukushima Medical University, Fukushima, Japan.|Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China.
authors.forename: Xiangmin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Hematology and Respiratory Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan.
authors.forename: Chie
authors.initials: C
authors.lastname: Nishioka
authors.affiliation: Medical Affairs Department, Asahi Kasei Pharma., Kanda Jinbocho, Chiyoda-ku, Tokyo, Japan.
authors.forename: Goichi
authors.initials: G
authors.lastname: Honda
authors.affiliation: Department of Hematology and Respiratory Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Yokoyama
authors.affiliation: Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China.
authors.forename: Lingyu
authors.initials: L
authors.lastname: Zeng
authors.affiliation: Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China.
authors.forename: Kailin
authors.initials: K
authors.lastname: Xu
authors.affiliation: Department of Hematology and Respiratory Medicine, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan. ikezoet@fmu.ac.jp.|Department of Hematology, Fukushima Medical University, Fukushima, Japan. ikezoet@fmu.ac.jp.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ikezoe
mesh_terms: D000818:Animals; D016207:Cytokines / Q000378:metabolism; D019610:Cytoprotection / Q000235:genetics*; D042783:Endothelial Cells / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D008970:Molecular Weight; D018919:Neovascularization, Physiologic / Q000235:genetics*; D009569:Nitric Oxide / Q000378:metabolism; D011485:Protein Binding; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015398:Signal Transduction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D018180:Thrombomodulin / Q000378:metabolism*
chemical_list: D016207:Cytokines; C523001:Gpr15 protein, mouse; D018836:Inflammation Mediators; D043562:Receptors, G-Protein-Coupled; D018180:Thrombomodulin; D009569:Nitric Oxide