同型半胱氨酸促进血管平滑肌细胞增殖的机制及辛伐他汀的干预作用

Homocysteine on vascular smooth muscle cell proliferation and effects of simvastatin

目的:探讨同型半胱氨酸促进大鼠血管平滑肌细胞(VSMC)增殖的机制及辛伐他汀的干预作用。方法:贴壁培养的大鼠原代VSMC随机分为3组。(1)对照组:用含10%胎牛血清的DMEM培养基(完全培养基);(2)同型半胱氨酸组:在完全培养基中加入同型半胱氨酸(0.05 mmol/L);(3)辛伐他汀组:在完全培养基中加入同型半胱氨酸(0.05 mmol/L)和辛伐他汀(10μmol/L)。培养24 h后,光学显微镜下观察各组细胞的形态;采用半定量PCR法检测c-myc、P27kip1的mRNA水平;用Western blot检测细胞周期蛋白(cyclin)D1、cyclin E、cyclin A和核增殖抗原(PCNA)的蛋白表达水平。结果:与对照组相比,同型半胱氨酸组c-myc mRNA水平上调,P27kip1 mRNA水平下调,下游cyclin D1、cyclin E、cyclin A和PCNA蛋白表达增加。与同型半胱氨酸组相比,辛伐他汀组上述检测指标均得到逆转。结论:同型半胱氨酸可促进大鼠VSMC c-myc、cyclin D1、cyclin E、cyclin A等增殖相关基因的表达,抑制P27kip1表达。辛伐他汀可逆转上述效应。

Objective：To explore the mechanism of homocysteine promoting the proliferation of rat vascular smooth muscle cells （VSMC） and intervention effects of simvastatin. Methods： Primary rat VSMC were divided into 3 groups. Cells in control group were cultured in DMEM with 10% fetal bovine serum. Cells in homoeysteine group were treated with 0. 05 mmol/L homocysteine, and cells in simvastatin group were treated with 0. 05 mmol/L homocysteine and 10 μmol/L simvastatin. Morphology of cells was observed under optical microscope. The mRNA levels of c-myc 和 P27-kip1 were analyzed by semi-quantitative PCR, and the protein levels of cyclin D1, cyclin E, cyclin A and PCNA were evaluated by Western blot. Results：Compared with control group, the mRNA level of c-myc and protein levels of cyclin D1, cyclin E, cyclin A and PCNA in homocysteine group were significantly increased, while the mRNA level of P27-kip1 was decreased. After treatment with simvastatin, P27-kip1 was upregulated compared with homocysteine group accompanied by the inhibition of c-myc, cyclin D1, cyclin E, cyelin A and PCNA. Conclusion= Homocysteine promotes the expression of proliferation associated genes such as c-myc, cyelin D1, eyclin E, cyclin A and PCNA and inhibits P27-kip1 expression, which can be reversed by simvastatin.