ABSTRACT
Objective:To investigate the expression of PTEN in atherosclerosis and its effect on the proliferation and apoptosis of vascular endothelial cell (VEC).Methods:The atherosclerotic mouse models were constructed,and the levels of PTEN in atherosclerotic tissues were detected by Real-time,PCR and Western blot;Rat VEC was treated with different concentrations of ox-LDL, cell proliferation activity was detected by MTT.VEC was transfected with PTEN overexpression vector(pSicoR-PTEN),processing cells with ox-LDL,the levels of PTEN was detected by Real-time,PCR and Western blot,cell proliferation was detected by MTT,apoptosis was detected by flow cytometry,the levels of p-STAT3,STAT3 and Cleaved Caspase-3 were detected by Western blot.Results:The level of PTEN in atherosclerotic tissue was lower than that in normal arterial tissue(P<0.05).The survival rate of VEC decreased obviously after treatment with different concentrations of ox-LDL, and the cell survival rate decreased with the increase of ox-LDL concentration.The expression of PTEN decreased in VEC after ox-LDL action,transfection of pSicoR-PTEN could increase the expression level of PTEN in VEC.The apoptotic rate of VEC increased after ox-LDL treatment,elevated levels of Cleaved Caspase-3 in cells,the level of p-STAT3 decreased,compared with normal VEC,and the difference was statistically significant (P<0.05).After transfection of pSicoR-PTEN,the survival rate and p-STAT3 level of VEC were significantly increased after ox-LDL treatment,but the apoptosis rate and the level of Cleaved Caspase-3 were significantly decreased,compared with the cells treated with pure ox-LDL,the difference was statistically significant(P<0.05).Conclusion:Downregulation of PTEN expression in atherosclerosis,PTEN inhibits the proliferation and apoptosis of VEC by ox-LDL,the mechanism of action may be related to the activation of STAT3 signaling pathway.