载脂蛋白C3在细胞炎症及渗出中的作用

The mortality of cardiovascular disease has become first which was higher than that of cancer nowadays around the world. Atherosclerosis (AS) is the basis of coronary heart disease (CHD), the inflammatory response impacted throughout the entire forming process of AS, chemoattractant and permeability of cell were prerequisite for the formation. Apolipoprotein C3 (APOC3) expressed on the surface of plasma lipoprotein particles. High expression of APOC3 in plasma could delay the precess of lipid metabolism as well as directly activate monocytes and endothelial cells, leading to increased adhesion between them. These results suggested that APOC3 involved in the process of formation of AS. The present study intended to investigate the following three aspects: 1.to stimulate vascular endothelial cell by APOC3 to investigate (1)the expression of inflammatory molecules to determine whether APOC3 participated in the inflammatory response,(2)the expression of related molecules which could cause cell chemotaxis and permeability to determine whether APOC3 promoted cell chemotaxis and permeability, 2.to investigate the relationship between the screened inflammatory molecule and permeability molecule, 3.to prove the effects of these molecules in the tissue level (experimental animals) which screened from cell. The the present study was designed to study the mechanism of how APOC3 involved in the inflammatory response and cell permeability in AS process, looking forward to find a link between lipid metabolism and immune inflammatory and cell permeability，so that providing a new idea and target for prevention and treatment of CHD.

心血管疾病的致死率已超过癌症位居第一，动脉粥样硬化（AS）是冠心病（CHD）的发生基础，炎症反应贯穿于整个形成过程，细胞趋化、渗出是其形成的必备条件。载脂蛋白C3（APOC3）表达于血浆脂蛋白颗粒表面，是CHD独立风险因子，高表达APOC3可延缓脂类代谢，直接引发单核细胞向内皮细胞粘附，提示APOC3参与AS形成过程。本课题拟从以下3个方面展开研究：1.以APOC3刺激血管内皮细胞（1）观察相关炎症分子表达，以确定APOC3是否参与炎症反应，（2）观察可引起细胞发生趋化、渗出的相关分子表达，以确定是否通过APOC3促进细胞趋化和渗出；2.检测筛选出的炎症分子与渗出相关分子的关系；3.从组织水平（实验动物）论证APOC3对筛选出的上述分子的效应。本研究旨在研究APOC3在AS进程中参与炎症反应、细胞渗出的机制，期待找到脂类代谢与免疫炎症、细胞渗出的连接分子，为CHD的防治提供新思路和新靶点。

在三年的实施过程中，本青年科学基金项目的研究进展顺利，按照原定计划，完成了项目的研究内容与预期目标。体外细胞培养，采用APOC3刺激血管内皮细胞，在动物组织水平成功检测炎症分子VCAM-1和ICAM-1表达改变；采用炎症因子TNF-α刺激血管内皮细胞，验证介导细胞趋化及渗出作用的JAM-1的表达改变；利用分子生物学技术，成功构建TNF-α-siRNA和JAM-1-siRNA的RNA干扰技术，成功探讨APOC3 通过调节炎症因子 TNF-α 的表达变化，进一步引起细胞紧密连接蛋白 JAM-1和ZO-1 的变化，细胞紧密连接蛋白的表达改变进而影响血管内皮细胞的趋化和渗出特性；通过蛋白抑制剂分别阻断 NF-kB、PI3K、JUK、ERK、P38 等主要信号通路关键蛋白，研究APOC3引起炎症的主要信号传导通路。不仅揭示了APOC3促进炎症分子TNF-α的表达作用，通过TNF-α作用JAM-1和ZO-1，在细胞炎症及渗出中有重要的作用，而且诱导内皮细胞紧密连接蛋白ZO-1的表达，破坏内皮细胞紧密连接完整性，引起内皮细胞功能障碍。为探讨动脉粥样硬化的临床防治思路提供了有效的理论依据。相关研究共录用发表标明资助的论文4篇，其中SCI论著2篇，国内核心期刊论文2篇；承担本项目期间，项目负责人当选为江苏省医学会检验分会青年委员，国家公派出国留学，较好地实现本项目的主要考核指标。