title: SDF-1alpha/CXCR4 decreases endothelial progenitor cells apoptosis under serum deprivation by PI3K/Akt/eNOS pathway.
abstract: Recent studies have demonstrated that stromal cell-derived factor-1alpha (SDF-1alpha)/CXCR4 interaction regulates multiple cell signal pathways and a variety of cellular functions such as cell migration, proliferation, survival and angiogenesis. In present study, we aimed to determine the effect of SDF-1alpha on endothelial progenitor cells (EPCs) apoptosis induced by serum deprivation and the implication of phosphoinositide 3-kinase (PI3K)/Akt and mitogen-activated protein kinases (MAPKs) signaling in this effect. EPCs were isolated and characterized. SDF-1alpha decreased EPCs apoptosis induced by serum deprivation in a dose-dependent manner and the inhibitory effect was CXCR4 dependent as confirmed by the total abolishment by AMD3100, a CXCR4-specific peptide antagonist. SDF-1alpha treatment also significant decreased caspase-3 expression and activity. The inhibitory effect of SDF-1alpha on EPCs apoptosis was nearly completely abolished by PI3K inhibitors (either Wortmannin or LY294002) and partially abolished by NOS inhibitor, N(G)-nitro-arginine methyl ester, whereas inhibitors of MAPKs had no significant effect on this inhibitory effect. The treatment of EPCs with SDF-1alpha resulted in time-dependent Akt, eNOS, extracellular-regulated kinase (ERK1/2), p38 MAPK and c-Jun N-terminal kinase (JNK) phosphorylations. These findings suggest that PI3K/Akt/eNOS activation, but not MAPKs activation, is required for the inhibitory effect of SDF-1alpha on EPCs apoptosis.
authors.affiliation: Department of Cardiology, Biomedical Research (Therapy) Center, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou 310016, Zhejiang Province, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zheng
authors.forename: Tao
authors.initials: T
authors.lastname: Dai
authors.forename: Binquan
authors.initials: B
authors.lastname: Zhou
authors.forename: Junhui
authors.initials: J
authors.lastname: Zhu
authors.forename: He
authors.initials: H
authors.lastname: Huang
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Guosheng
authors.initials: G
authors.lastname: Fu
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D018929:Cell Culture Techniques; D054377:Chemokine CXCL12 / Q000494:pharmacology*; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007963:Leukocytes, Mononuclear; D020935:MAP Kinase Signaling System / Q000502:physiology*; D052250:Nitric Oxide Synthase Type III / Q000502:physiology; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology; D019718:Receptors, CXCR4 / Q000502:physiology; D013234:Stem Cells / Q000187:drug effects*
chemical_list: C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; D019718:Receptors, CXCR4; D052250:Nitric Oxide Synthase Type III; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt