Activation of the phosphatidylinositol 3-kinase/protein kinase Akt pathway mediates CD151-induced endothelial cell proliferation and cell migration.

We previously reported that CD151 promotes neovascularization and improves blood perfusion in rat hind-limb ischemia model, but the precise mechanism is still unclear. Endothelial cell proliferation and cell migration play critical roles in angiogenesis. Many growth factors and hormones have been shown to regulate cell proliferation, cell migration and angiogenesis, including the activation of eNOS activity, via the PI3K/Akt signaling pathway. Whether CD151 induces cell proliferation and cell migration via PI3K/Akt signaling pathway is not known. Here we showed that CD151 promotes human umbilical vein endothelial cell (HUVEC) proliferation, migration and tube formation in vitro, accompanied by increased phosphorylation of Akt and eNOS, leading to increased eNOS activity and nitric oxide (NO) levels after rAAV-CD151 infection, whereas infection with rAAV-anti-CD151 attenuated the effects of CD151, which suggested that CD151 can activate PI3K/Akt pathway. Moreover, inhibitors of PI3K (LY294002) and eNOS (l-NAME) can attenuate CD151-induced cell proliferation and cell migration. The results suggested that activation of PI3K/Akt signaling pathway mediates CD151-induced cell proliferation and migration.