The role of heat shock protein 27 phosphorylation in the proliferation and apoptosis of human umbilical vein endothelial cells induced by Visfatin

Abstract

ObjectiveTo study the mechanism of heat shock protein 27 (HSP27) phosphorylation in the visfatin-induced proliferation and its protective effect against high-glucose induced apoptosis in HUVECs. MethodsHuman umbilical vascular endothelial cells (HUVECs) were isolated from umbilical veins and treated with visfatin. The proliferation of HUVECs was measured by the MTT assay and the apoptosis of HUVECs was detected by TUNEL assay. The phospho-HSP27 expression was detected by Western blot. The siRNA was used to knock down HSP27 expression in HUVECs. ResultsVisfatin significantly promoted the HUVECs growth and inhibited the high-glucose induced apoptosis of HUVECs in a dose-dependent manner. Also, visfatin upregulated the expression of HSP27 phosphorylation in a time-dependent manner, with a peak at 12 h. Visfatin prompted cell proliferation and exerted a protective effect against high-glucose induced apoptosis in HUVECs, which was significantly blocked by siRNA-HSP27. The HSP27 phosphorylation induced by visfatin was also blocked by the specific PI3K/Akt inhibitor LY294002 and ERK 1/2 inhibitor U0126. Furthermore, the visfatin impact on HUVECs as above were also blocked by LY294002 and U0126. ConclusionVisfatin prompted cell proliferation and exerted a protective effect against high-glucose induced apoptosis in HUVECs through HSP27 phosphorylation. PI3K/Akt and ERK1/2 are important signaling pathways that contribute to HSP27 phosphorylation.