Vascular endothelial cell senescence mediated by integrin β4 in vitro

To understand whether integrin β4 is involved in vascular endothelial cell (VEC) senescence, we examined integrin β4 level changes, as well as P53 and reactive oxygen species (ROS) levels and alterations of phosphatidylcholine-specific phospholipase C (PC-PLC) activity before and after knocking-down integrin β4 by small interfering RNA. We found integrin β4, P53 and ROS levels increased significantly, while Ca2+-independent PC-PLC activity obviously decreased during VEC senescence. On the other hand, integrin β4 down-regulation attenuated the senescence phenotype and reversed Ca2+-independent PC-PLC activity, and P53 and ROS levels. The data suggested that integrin β4 might mediate VEC senescence through depressing Ca2+-independent PC-PLC and elevating the levels of P53 and ROS.