title: Chlamydia pneumoniae infection induces vascular smooth muscle cell migration via Rac1 activation.
abstract: Chlamydia pneumoniae infection has been shown to be associated with the development of atherosclerosis by promoting the migration of vascular smooth muscle cells (VSMCs). However, how C. pneumoniae infection induces VSMC migration is not fully understood. A primary role of Ras-related C3 botulinum toxin substrate 1 (Rac1) is to generate a protrusive force at the leading edge that contributes to cell migration. Whether Rac1 activation plays a role in C. pneumoniae infection-induced VSMC migration is not well defined. In the present study, we therefore examined Rac1 activation in C. pneumoniae-infected rat primary VSMCs and the role of Rac1 activation in C. pneumoniae infection-induced VSMC migration. Glutathione S-transferase pull-down assay results showed that Rac1 was activated in C. pneumoniae-infected rat primary VSMCs. A Rac1 inhibitor, NSC23766 (50 µM,) suppressed Rac1 activation stimulated by C. pneumoniae infection, and thereby inhibited C. pneumoniae infection-induced VSMC migration. In addition, C. pneumoniae infection-induced Rac1 activation in the VSMCs was blocked by LY294002 (25 µM), an inhibitor of phosphatidylinositol 3-kinase (PI3K). Taken together, these data suggest that C. pneumoniae infection promotes VSMC migration, possibly through activating Rac1 via PI3K.
authors.affiliation: Department of Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, PR China.
authors.forename: Junxia
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, PR China.
authors.forename: Haiwei
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, PR China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, PR China.
authors.forename: Tengteng
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, PR China.
authors.forename: Beibei
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China.
authors.forename: Xiankui
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, PR China.
authors.forename: Junyan
authors.initials: J
authors.lastname: Wei
authors.affiliation: Department of Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, PR China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002465:Cell Movement; D002478:Cells, Cultured; D016993:Chlamydophila pneumoniae / Q000254:growth & development*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism / Q000382:microbiology* / Q000502:physiology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051381:Rats; D020830:rac1 GTP-Binding Protein / Q000378:metabolism*
chemical_list: D019869:Phosphatidylinositol 3-Kinases; C499134:Rac1 protein, rat; D020830:rac1 GTP-Binding Protein