富含亮氨酸重复蛋白8A在内皮老化及氧化应激中的作用机制研究

内皮老化是心血管疾病发生的重要危险因素，氧化应激在其发生发展过程中扮演重要作用。预实验发现内皮富含亮氨酸重复蛋白8A(LRRC8A)参与老化小鼠的内皮功能及氧化应激的调控，并且敲低内皮LRRC8A引起p-p66shc和Rac1蛋白表达升高，但具体的分子机制仍有待进一步揭示。因此，我们提出科学假说：内皮LRRC8A通过GRB2/p66shc/Rac1/ROS信号通路参与内皮老化及氧化应激的调控。本项目拟在细胞与转基因动物层面，系统研究：1）在老化内皮细胞水平，验证LRRC8A对上述信号通路的调控作用；2）在内皮特异性敲除LRRC8A的动物水平，建立自然老化模型，阐明LRRC8A调控内皮老化及氧化应激的作用及分子机制；3）LRRC8A激动剂C2-Ceramide能否改善老化动物内皮功能及氧化应激。本项目的实施将丰富内皮调控氧化应激理论，为自然老化相关心血管疾病的防治提供新靶点。

Endothelial Aging is an important risk factor for cardiovascular disease and oxidative stress plays an important role in the development of vascular endothelial aging. Our preliminary data indicate that LRRC8A might be involved in the regulation of endothelial function and oxidative stress of aged mice. Knockdown of LRRC8A results in the up-regulation of p66shc and Rac1. However, the underlying molecular mechanism remains unclear. We hypothesize that LRRC8A participates in the regulation of endothelial aging and oxidative stress via p66shc/Rac1/ROS signaling pathway. To test the hypothesis, we will employ multiples techniques at the cellular level, aorta rings and transgenic mice, to:1) investigate how LRRC8A regulates p66shc/Rac1/ROS signaling pathway at the level of aging endothelial cells; 2) elucidate the role and molecular mechanism of LRRC8A in the regulation of endothelial aging and oxidative stress in aged wildtype (WT) and endothelium-specific LRRC8A knockout (KO) mice; 3）explore whether LRRC8A agonist C2-Ceramide improves endothelial function and oxidative stress in aging animals. In summary, the implementation of this project will extend our understanding of the regulatory mechanism of endothelium on oxidative stress and will provide a new therapeutic target for cardiovascular diseases related to natural aging.