The role of p66shc in hydrogen peroxide-induced endothelial dysfunction

Abstract

Objective To study the effect and its possible mechanism of p66shc on endothelial dysfunction induced by hydrogen peroxide(H2O2). Methods Human umbilical vein endothelial cells(HUVEC)were used and cultured.HUVEC cells were untreated(control group)or treated with four groups of H2O2, H2O2 plus protein kinase C(PKC)inhibitors, H2O2 plus PKC activator, H2O2 plus P38 inhibitor for 30 minutes respectively, and cells were collected after 24 hours.The apoptosis, viability, proliferation of HUVEC were detected with immune fluorescent staining, MTT and Ki-67 respectively.P66shc and ser36 p66shc(p-p66shc)protein expressions were assessed using Western blotting.P66shc mRNA expression was measured with real-time quantitative polymerase chain reaction(RT-PCR). Results H2O2 induced HUVEC dysfunction which decreased HUVEC proliferation and increased the apoptosis of HUVEC.The expressions of p66shc, p-p66shc protein and p66shc mRNA were significantly increased after treating with H2O2.PKC inhibitor inhibited a H2O2-induced HUVEC dysfunction through increasing HUVEC proliferation activity and reducing cell apoptosis.The expressions of p66shc, p-p66shc protein and p66shc mRNA were significantly decreased after treating with H2O2 plus PKC inhibitor.PKC activator enhanced H2O2-induced HUVEC dysfunction and increased the expressions of p66shc.P38 inhibitor had no obvious effect on H2O2-induced HUVEC dysfunction and the expressions of p66shc. Conclusions p66shc may play an important regulatory role in endothelial dysfunction caused by H2O2.P66shc may regulate a H2O2-induced endothelial dysfunction through PKC signal pathway. Key words: Endothelial cells; Hydrogen peroxide