摘要
目的探讨高同型半胱氨酸血症(hyperhomocysteinemia,HHcy)致血管平滑肌细胞(vascular smooth muscle cells,VSMC)增殖在动脉粥样硬化发病中的机制。方法整体水平实验:82例研究对象分为动脉粥样硬化(atherosclerosis,AS)组54例,对照组28例。荧光生化法检测血浆总同型半胱氨酸(total homocysteine,tHcy)水平,甲基化特异的PCR(Methy-specificPCR,MSP)法检测雌激素受体α(estrogen receptor-α,ER-α)启动子区CpG岛的甲基化状态。细胞水平实验:体外培养的人脐动脉VSMC,用不同浓度同型半胱氨酸(homocy steioe,Hcy)处理,MTT法观察Hcy对平滑肌细胞生长的影响,MS-PCR法和Rt-PCR法检测ER-α基因启动子区甲基化程度及mRNA的表达。结果整体水平实验中,AS患者中甲基化率为70.4%,对照组甲基化率为28.6%,差异具有统计学意义(P<0.05)。细胞水平实验中,MTT结果显示Hcy对VSMC具有明显促增殖效应。Hcy显著增加ER-α基因启动区的甲基化修饰,并使ER-αmRNA的表达进行性减少。结论 Hcy通过干扰DNA的甲基化修饰,使ER-a基因高甲基化可能是高同型半胱氨酸血症促使VSMC增殖,并引起动脉粥样硬化的重要机制。
Objective To investigate the mechanism of proliferation of vascular smooth muscle cells （VSMCs）induced by hyperhomocysteinemia in atherosclerosis. Methods In the experiment, 82 cases were recruited, including 54 atherosclerosis patients and 28 healthy control subjects. Total homocysteine （ tHey ） was dectected by fluorescent - biochemical method. The methylation status of CpG islands in ER-a gene promoter region was analyzed by methylation -specific PCR（MSP）. During the vitro experiment, cultured VSMCs were treated by different concentrations of Hcy. The proliferative activities of VSMCs were examined by M3T assay and the expres- sions of ER - amRNA of VSMCs were detected by RT - PCR. Results In vivo, hypermethylation of ER - agene promoter region was found in 38 of the 54 atherosclerosis patients, with a methylation frequency of 70.4% , while the methylation frequency in healthy controls was only 28.6%. In vitro, Hcy obviously induced methylation in the promoter region of the ER - agene in VSMC, and the expression of ER - a mRNA was correspondingly down - regulated. Conclusion Hcy can lead to hypermethylation modification of of ER - a gene, which may be an important mechanism of HHcy - induced proliferation of VSMC and the development of AS.
出处
《武警医学》
CAS
2010年第10期837-841,共5页
Medical Journal of the Chinese People's Armed Police Force
