内皮酯酶在动脉粥样硬化发生和发展中作用研究

内皮酯酶(EL)是内皮细胞等分泌的脂肪酶，与高密度脂蛋白(HDL)代谢密切相关。既往实验研究和临床观察，未能确定EL在动脉粥样硬化疾病中作用。家兔脂质代谢特征与人类相似，适合EL研究。本课题拟分别制作肝脏和巨噬细胞特异表达人类EL基因的2个转基因家兔模型，高胆固醇饲料诱导动脉粥样硬化，观察转基因家兔HDL代谢和动脉粥样硬化斑块特征，研究EL与动脉粥样硬化疾病的关系；分离培养转基因家兔肝细胞、巨噬细胞，观察EL对细胞膜受体ABCA1、SR-B1以及细胞内胆固醇流出率影响；分离培养人脐静脉内皮细胞(HUVECs)，利用重组腺病毒感染和iRNA技术，上调或下调HUVECs中EL水平，观察EL在正常、过表达、低表达情况下对炎症分子、NO信号分子和亚硝基化蛋白水平影响。在分子、细胞以及整体转基因动物水平上，系统研究EL在动脉粥样硬化形成和发展中分子病理生理学机制，为人类心血管疾病探索新的治疗靶点。

Endothelial lipase (EL), which is a newly identified member of the lipase family, plays an important role in high-density lipoprotein metabolism, which is important in the initiation and development of atherosclerosis. However, current data from mouse experimentation and human clinical study on the role of EL in atherosclerosis are not conclusive. The current study is designed: 1) to create two transgenic (Tg) rabbit model overexpressing human EL in rabbit liver and macrophage, high cholesterol diet will be used to induce Tg rabbit atherosclerosis, to investigate the role of EL in the pathogenesis of atherosclerosis; 2) to collect the hepatocyte and macrophage from Tg rabbits after cholesterol diet fed 16 weeks, and measure the expression of scavenger receptor type B class 1 (SR-B1), ABC transporter A1 (ABCA1) and cholesterol mass efflux changes in hepatocyte and macrophage; 3) to collect and culture human umbilical vein endothelial cells (HUVECs), up- and down-regulation expression of EL in HUVECs will be mediated by adenovirally-driven EL and siRNA, to determine the change of inflammatory, nitric oxide (NO) signaling molecules, as well as protein s-nitrosylation in HUVECs. This study will be performed in vitro and in vivo to evaluate the role of EL in the formation and development of atherosclerosis, which might be a novel therapeutic target for human cardiovascular diseases.