内皮祖细胞外泌体在动脉内皮损伤修复和糖尿病动脉粥样硬化发生中的作用

The incidence of type 2 diabetes was increased year by year. The atherosclerosis induced by type 2 diabetes becomes a major cause of cardiovascular events. The exosomes from endothelial progenitor cells (EPCs) richly contain miRNAs, which can induce angiogenesis and endothelial repair. In our preliminary data, we found that the TRPC5 channel and phospholipid scramblase 1 (PLSCR1) form a signaling complex in the cell membrane to regulate the release of exosomes. The expression level of TRPC5-PLSCR1 complex was decreased in EPCs which were cultured in the high glucose medium. In addition, the release of the exosome was also significantly reduced. Therefore, we speculate that the release of EPC’s exosomes mediated by TRPC5-PLSCR1 has an important role in the development of the atherosclerosis induced by type 2 diabetes. Thus, we plan through the cell and animal experiments to clarify (1) the change of TRPC5-PLSCR1 complex expression and the functional role of the complex in the secretion of exosomes in EPCs in type 2 diabetes; (2) the change of the content and types of miRNAs in EPCs in type 2 diabetes; (3) the effect and underlying mechanism of the exosome miRNAs from EPCs to regulate the inflammatory reaction and oxidative stress in the vascular endothelial cells in diabetic animals and high glucose culture condition; (4) the effect of EPC’s exosome miRNAs and TRPC5-PLSCR1 complex on the repair of arterial endothelial injury and the development of atherosclerosis. This study contributes to the understanding of the mechanism of exosome release and unknown role of endothelial progenitor cell exosomes in the repair of vascular endothelial injury and in the development of atherosclerosis.

2型糖尿病发病率逐年升高，其导致的动脉粥样硬化是引起心脑血管事件的重要原因。内皮祖细胞（EPC）外泌体富含miRNA，可促进血管新生和内皮修复。我们前期工作发现TRPC5通道和磷脂爬行酶1（PLSCR1）形成复合物促进外泌体释放，高糖培养EPC使TRPC5-PLSCR1表达降低、外泌体释放减少。由此推测TRPC5-PLSCR1介导的EPC外泌体释放在2型糖尿病动脉粥样硬化发生中可能有重要作用。为此计划通过细胞和动物实验阐明（1）TRPC5-PLSCR1在2型糖尿病EPC中改变；（2）2型糖尿病EPC外泌体miRNA含量和种类改变；（3）EPC外泌体miRNA对糖尿病动物和高糖培养内皮细胞炎症反应和氧化应激调节作用；（4）EPC上TRPC5-PLSCR1及其外泌体miRNA在内皮损伤修复和粥样硬化发生中作用。该研究有助于了解外泌体释放机制、EPC外泌体在内皮损伤修复和动脉粥样硬化发生中作用。

2型糖尿病发病率逐年升高，其导致的动脉粥样硬化是引起心脑血管事件的重要原因。内皮祖细胞（EPC）外泌体富含miRNA，可促进血管新生和内皮修复。我们前期工作发现TRPC5通道和磷脂爬行酶1（PLSCR1）形成复合物促进外泌体释放，高糖培养EPC使TRPC5-PLSCR1表达降低、外泌体释放减少。由此推测TRPC5-PLSCR1介导的EPC外泌体释放在2型糖尿病动脉粥样硬化发生中可能有重要作用。为此计划通过细胞和动物实验阐明（1）TRPC5-PLSCR1在2型糖尿病EP C中改变；（2）2型糖尿病EPC外泌体miRNA含量和种类改变；（3）EPC外泌体miRNA对糖尿病动物和高糖培养内皮细胞炎症反应和氧化应激调节作用；（4）EPC上TRPC5-PLSCR1及其外泌体mi RNA在内皮损伤修复和粥样硬化发生中作用。该研究有助于了解外泌体释放机制、EPC外泌体在内皮损伤修复和动脉粥样硬化发生中作用。为此，本研究进行如下三个研究：（1）观察糖尿病患者外周血和小鼠内皮祖细胞中外泌体miRNA含量和种类改变；（2）检测正常小鼠内皮祖细胞外泌体对糖尿病小鼠和高糖原代培养的小鼠血管内皮细胞炎症反应和氧化应激的调节作用；（3）检测正常小鼠内皮祖细胞分泌的外泌体和TRPC5-PLSCR1复合物在动脉内皮损伤和粥样硬化修复中的作用通过研究。结果（1）揭示了2型糖尿病患者外泌体miRNA含量和种类改变；（2）阐明正常小鼠内皮祖细胞外泌体miRNA含量和种类；（3）发现正常小鼠内皮祖细胞外泌体显著改善糖尿病小鼠和高糖原代培养的血管内皮细胞炎症反应、氧化应激和内皮依赖性舒张；（4）阐明正常小鼠内皮祖细胞外泌体对2型糖尿病动脉粥样硬化内皮功能的修复作用，以及TRPC5在外泌体分泌中的意义，为临床提供了重要的潜在治疗靶点。