脑血管内皮细胞异常与缺血性脑卒中发病密切相关，最新研究表明miR125a-5p在脑血管内皮细胞中能调控重要炎症因子表达，并且在脑卒中易感大鼠动脉中低表达；我们的前期工作发现，miR125a-5p过表达能影响脑血管内皮细胞多种生物学功能。这些提示miR125a-5p能够调控脑血管内皮细胞功能，并可能借此参与缺血性脑卒中发病。此外，miRNAs能通过细胞膜微粒进行信息传递或作为疾病分子标记。因此，本实验首先通过体外敲除实验验证miR125a-5p功能，并检测miR125a-5p调控机制；其次，研究miR125a-5p对脑血管内皮细胞膜微粒功能影响，深入研究miR125a-5p作用；最后，对缺血卒中患者循环系统微粒及其中miR125a-5p进行检测，分析miR125a-5p与缺血性脑卒中发生发展的相关性。本研究能够揭示miR125a-5p功能及其调控机制，为脑卒中基础研究到临床应用转化奠定基础。

Brain vascular endothelial cell dysfunction is closely associated with the development of ischemic stroke. The latest research showed that miR125a-5p can suppress the expression of certain inflammatory factor in brain vascular endothelial cell, and it is down regulated in the aorta of stroke prone rats. In our previous studies, we found that overexpression of miR125a-5p could regulate various activities of brain vascular endothelial cell. These suggest that miR125a-5p could regulate brain vascular endothlial cell function，by which it may participate in the pathogenesis of ischemic stroke. What’s more, miRNAs can mediate cell to cell communication or act as predictive biomarkers by the way of being transported by microparticles. Therefore,in our present study,we will first detect the effect of miR125a-5p knock down on the brain vascular endothelial cell behaviors to further strengthen our previous findings ,and to determine the underlying mechenisms. Second, we are going to study the impact of miR125a-5p on the function of microparticles released from brain vascular endothelial cells to get some insight into the role of extracellular miR125a-5p in ischemic stroke development. Finally, the endothelial microparticles and the expression miR125a-5p in them will be detected in ischemic stroke patients, and the relationship between miR125a-5p and ischemic stroke development will be analyzed. The results of our study will elucidate the role of miR125a-5p and the underlying mechenisms, which will help to transform the basic reseach of stroke to clinical application.