摘要
目的观察同型半胱氨酸(Hcy)对大鼠雌激素受体α(ERα)基因表达和其启动子CpG岛甲基化的影响。方法高效液相色谱仪检测血浆Hcy水平;RT-PCR和甲基化特异性PCR(MSP)分别检测ERαmRNA表达水平及基因启动子CpG岛的甲基化状态。结果去卵巢和给予甲硫氨酸饮食均可升高大鼠血浆Hcy水平。去卵巢和Hcy均可使大鼠ERαmRNA表达减少,但5′-Aza可使细胞ERαmRNA表达增多。假手术组大鼠主动脉ERα基因启动子有2例(20%)存在甲基化,去卵巢组有3例(30%)存在甲基化,而去卵巢+Hcy组有6例(60%)存在甲基化,对照组细胞ERα启动子CpG岛完全去甲基化,Hcy组细胞甲基化增强,5′-Aza使细胞去甲基化。结论Hcy可经甲基化修饰方式下调去卵巢大鼠主动脉ERαmRNA表达。
Objective To observe the effects of homocysteine on the expression of estrogen receptor alpha （ERα） mRNA and the CpG island methylation of ERα gene promotor region in rats. Methods The serum level of homocysteine in rats was measured by reversed- phase HPLC. RT-PCR and methylated specific PCR （MSP） were applied to assay mRNA expression and the methylation status in promoter CpG island of ERα gene in aorta and cultured rat aortic smooth muscle cells （RASMCs）. Results The homocysteine level was increased in ove and ove ＋ H groups （P 〈0.05 or P 〈0.01 ）. The mRNA expression of ERα decreased in both ove and Hcy groups,while increased in cells treated with 5＇-Aza. The methylation of CpG island in promoter region of ERα gene in aorta increased 30% in ove group and 60% in ove ＋ H group as compared with that in sham group. The CpG island in ERα gene promotor region was completely demethylated in control RASMCs, and Hcy induced hypermethylation, while 5＇-Aza produced demethylation. Conclusion Homocysteine downreglates the ERα expression in aorta of ovariectomized rats by a methylation modification manner.
出处
《基础医学与临床》
CSCD
北大核心
2008年第3期243-246,共4页
Basic and Clinical Medicine
基金
河北省科技厅资助项目(2006090008)
