Effects of Homocysteine on the Apoptosis Cultured Human Vascular Smooth Muscle Cells and the Expression of Bax and Bcl-2 Gene

Objective To investigate the effects of Homocysteine (Hcy) on the apoptosis of human vascular smooth muscle cells (HVSMCs) cultured in vitro and expression of bax and bcl-2 gene.Methods HVSMCs were cultured in vitro,the rate of apoptosis of HVSMCs was detected by the way of flow cytometry;the expression of bax and bcl-2 mRNA of HVSMCs was detected by the way of reverse-transcriptase polymerase chain reaction (RT-PCR).Results The rate of apoptosis of HVSMCs incubated with 0,100,200,500,1 000μmol/L Hcy for 24 h was (2.68±0.23)%,(2.79±0.12)%,(8.45±2.41)%,(13.37±4.71)%,(23.75±5.56)%,respectively,revealing that Hcy could induce the apoptosis of HVSMCs in a concentration-dependent manner;the expression of bax mRNA was 0.86±0.01,0.92±0.03,1.51±0.02,1.82±0.03,1.91±0.02,respectively,and the expression of bcl-2 mRNA was 1.38±0.04,1.32±0.03,1.28±0.03,1.21±0.02,1.09±0.02,respectively,revealing that Hcy could up-regulate bax gene of VSMCs significantly and down-regulate bcl-2 gene relatively weakly,resulting in an enhancement of the ratio of bax/bcl-2.Conclusion Hcy can induce the apoptosis of HVSMCs by up-regulating the expression of bax gene,which may be one of the mechanisms involved in atherosclerotic effects of Hcy.