ASAP3保护心肌缺血再灌注损伤的功能与机制研究

心肌缺血再灌注损伤（MIRI）发病急，致死率高，危害严重。Rho家族GTP酶RAC1活化促进ROS积聚、Ca2+超载是导致MIRI的重要原因，心肌缺血再灌注能够激活RAC1，然而其调控的机制尚不清楚。本课题组前期研究，通过ITRAQ蛋白质组学筛选，qRT-PCR、WB验证，发现GTP酶活化蛋白家族成员ASAP3在心肌细胞缺氧复氧后表达降低；过表达ASAP3后，RAC1活化降低，ROS水平下降；提示我们心肌缺血再灌注可能是通过抑制ASAP3表达激活RAC1，进而促进MIRI。在此前期研究基础上，我们拟将通过CHIP、DNA pull-down、RAC1通路抑制以及挽救实验等明确ASAP3在缺血再灌注损伤中的保护作用，揭示缺血再灌注抑制ASAP3表达激活RAC1促MIRI的机制，探索ASAP3成为MIRI潜在治疗靶点的可能，为MIRI提供新理论与潜在治疗手段。

Myocardial Ischemia-Reperfusion Injury (MIRI) has a high mortality rate and serious harm. The activation of RAC1 caused by ischemia-reperfusion is an important cause of MIRI. RAC1 activation promotes reactive oxygen radicals, Ca2 + overload, premyocardial fibrosis, and myocardial infarction. And SPA-1 can specifically inhibit the activation of RAC1. We previously found by proteomics ITRAQ cardiomyocytes hypoxia increases SPA-1 expression, and is further confirmed by qPCR and western blot. By silencing and overexpressing SPA-1, it was found that SPA-1 effectively prevented RAC1 activation caused by ischemia-reperfusion and reduced ROS levels. However, the molecular mechanism of ischemia-reperfusion promoting SPA-1 expression has not yet been elucidated. We will explore the mechanism of ischemia-reperfusion promoting SPA-1 expression through CHIP and DNA pull-down experiments，using the RAC1 pathway inhibition experiment to confirm the role of SPA-1 in the regulation of ischemia-reperfusion signaling pathway. At the same time combining rat experiments and clinical data explores the possibility of SPA-1 as a target for the prevention and treatment of MIRI, and provides new ideas for reducing or avoiding MIRI.