同型半胱氨酸对内皮细胞中可溶性表氧化物水解酶的转录调控机制研究

项目名称： 同型半胱氨酸对内皮细胞中可溶性表氧化物水解酶的转录调控机制研究

项目编号： No.81200224

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 医学一处

项目作者： 张东红

作者单位： 汕头大学

项目金额： 23万元

中文摘要： 高同型半胱氨酸血症可介导血管内皮细胞功能紊乱而启动动脉粥样硬化发生，其机制包括表观遗传学修饰，内质网应激和氧化应激等。可溶性表氧化物水解酶(sEH)可将花生四烯酸代谢产物表氧-二十碳三烯酸(EETs)水解为无活性的代谢物，从而失去其心血管保护作用。我们前期研究证实，同型半胱氨酸(Hcy)可转录性上调sEH表达，降低EETs含量，参与内皮细胞的激活反应。本研究拟利用Hcy急/慢刺激原代人脐静脉内皮细胞功能紊乱和相应的高同型半胱氨酸血症C57小鼠为模型，采用生物信息学、表观遗传学和多种分子生物学技术，从DNA甲基化修饰和内质网应激的相互作用，探讨Hcy介导的sEH基因启动子区活化转录因子6(ATF6)结合位点的甲基化修饰反应与内质网应激，特别是ATF6剪切/入核反应，对sEH基因转录表达的影响。明确Hcy对sEH转录调控机制和位点，以期为Hcy导致动脉粥样硬化发病提供新的理论基础和治疗途径。

中文关键词： 同型半胱氨酸；DNA甲基化；可溶性表氧化物水解酶；内皮细胞激活；内皮细胞衰老

英文摘要： Hyperhomocysteinemia (HHcy) causes vascular endothelial disfunction,which participates in the development of atherosclerosis and other vascular diseases. The involved mechanisms include DNA methylation, endoplasmic reticulum (ER) stress and oxidative stress. Soluble epoxide hydrolase (sEH) is a major enzyme to hydrolyze epoxyeicosatrienoic acids and attenuate their cardiovascular protective effects. Our previous study revealed that homocysteine(Hcy) transcriptionally upregulated sEH expression, decreased EETs content and leaded to endothelial activation. This study carries out the model of endothelium dysfunction through Hcy-stimulated human umbilical vein endothelial cells，actually or chronically, and established HHcy mice. We are aimed to explore the detail sEH regulated mechanisms by Hcy, including DNA methylated modification and ER stress and their cross-talk using bioinformatics, epigentics and molucular biology technologies. We will define the binding sites of activating transcription factor-6 (ATF6) on the promoter of sEH specifically under the affection of Hcy induced DNA hypomethylation modification and ER stress,especially ATF6 nuclear translocation. Discovery the precise mechanism underlying Hcy-upregulated sEH may be provide a novel theoretical basis and specific therapeutic targets for Hcy-associate

英文关键词： Homocysteine；DNA methyltion；Soluble epoxide hydrolase；endothelial activity；endothelial senescence