title: Participation of PI3K and ERK1/2 pathways are required for human brain vascular smooth muscle cell migration.
abstract: Human brain vascular smooth muscle cell (HBVSMC) migration contributes to angiogenesis and several pathological processes in the brain. However, the molecular mechanism of angiogenesis, in which smooth muscle cell contributes, remains unclear. Our study investigates the role of vascular endothelial growth factor (VEGF) in the HBVSMC migration and elucidates the chemotactic signaling pathway mediating this action. We used the in vitro 'scratch' wound method to detect the HBVSMC migration. VEGF(165) (1-40ng/ml) induced the HBVSMC migration in a dose-dependent manner (P<0.05). VEGF(165) does not induce HBVSMC proliferation. Wortmannin, a specific phosphatidylinositol 3-kinase (PI3K) inhibitor, significantly inhibited serine/threonine kinase Akt/protein kinase B (PKB) phosphorylation and reduced HBVSMC migration into the wound edge following VEGF(165) stimulation (P<0.05). PD98059, an extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor, also significantly inhibited ERK1/2 phosphorylation and reduced the numbers of SMC migration. Parallel distance measurement showed that VEGF(165) induced HBVSMC migration significantly reduced due to inhibition of PI3K or ERK1/2 phosphorylation (P<0.05). Our results demonstrate that VEGF(165) could induce HBVSMC migration but not proliferation in vitro. Inhibiting Akt/PKB or ERK1/2 phosphorylation could reduce VEGF(165) induced HBVSMC migration. We provide the first evidence that activation of PI3K or ERK1/2 pathways are a crucial event in VEGF(165) mediated signal transduction leading to HBVSMC migration.
authors.affiliation: Department of Anesthesia and Perioperative Care, Center for Cerebrovascular Research, University of California, San Francisco, 1001 Potrero Avenue, 3C-38, San Francisco, CA 94110, USA. gyyang@anesthesia.ucsf.edu
authors.forename: Guo Yuan
authors.initials: GY
authors.lastname: Yang
authors.forename: Jianhua S
authors.initials: JS
authors.lastname: Yao
authors.forename: Madeleine
authors.initials: M
authors.lastname: Huey
authors.forename: Tomoki
authors.initials: T
authors.lastname: Hashimoto
authors.forename: William L
authors.initials: WL
authors.lastname: Young
mesh_terms: D000730:Androstadienes / Q000494:pharmacology; D002560:Cerebrovascular Circulation; D002633:Chemotaxis / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000166:cytology* / Q000201:enzymology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors / Q000502:physiology; D000077191:Wortmannin
chemical_list: D000730:Androstadienes; D004791:Enzyme Inhibitors; D005419:Flavonoids; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D042461:Vascular Endothelial Growth Factor A; D000077191:Wortmannin; C467484:VEGFA protein, human; C494918:AKT1 protein, human; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one