缺氧/复氧预处理诱导血管内皮细胞外泌体转运miR-193a-3p抑制MMP-14减轻脑缺血再灌注损伤

Cerebral ischemia reperfusion injury (CIRI) affects the prognosis of stroke patients seriously. Remote ischemic postconditioning (RIPoC) has great benefits for CIRI prevention and treatment, and its application is promising, but the mechanism is not completely elucidated. Our previous study showed that hypoxia/reoxygenation (H/R) preconditioning acts on vascular endothelial cells (VEC), which is similar to RIPoC in vitro，the exosomes (VEC-exoH/R) induced by it have a brain protection effect, which is likely to be achieved through VEC-exoH/R transportion of high concentration of miR-193a-3p through the blood-brain barrier into the brain tissue，and then downregulate the expression of MMP-14 protein. In this study, the VEC-exoH/R will be prepared and used on CIRI rat model to verify the effect of VEC-exoH/R on CIRI. Mir-193a -3p overexpressed lentivirus will be used to verify the miR-193a-3p targeting MMP-14 and transporting it to brain tissue with VEC-exoH/R. This study will improve the protection mechanism of RIPoC deeply and provide a novel clue for the prevention and treatment of CIRI.

脑缺血再灌注损伤（CIRI）严重影响脑卒中患者预后。远端缺血后处理（RIPoC）对CIRI的防治大有裨益，应用前景广阔，但机制未完全阐明。我们前期研究显示，以缺氧/复氧（H/R）预处理模拟体内RIPoC作用于血管内皮细胞（VEC），其诱导产生的外泌体（VEC-exoH/R）具有脑细胞保护作用，初步证据提示是通过VEC-exoH/R 转运高浓度的miR-193a-3p透过血脑屏障进入脑组织下调神经细胞膜上基质金属蛋白酶-14（MMP-14）实现。本研究拟制备VEC-exoH/R作用于大鼠CIRI模型，求证VEC-exoH/R对CIRI的防治效果；同时构建miR-193a-3p过表达慢病毒验证miR-193a-3p靶向调控MMP-14，并能随VEC-exoH/R运输至脑组织有效减轻CIRI。本研究将从侧面进一步完善RIPoC的脑保护机制，并为CIRI的防治提供一条新思路。

脑缺血再灌注损伤（CIRI）严重影响脑卒中患者预后。最近的研究揭示了长链非编码RNA（lncRNAs）与CIRI关系密切。本研究发现：1、在CIRI的细胞和大鼠模型中NEAT1 mRNA表达上调。 2、抑制NEAT1减轻CIRI引起的神经细胞损伤。3、MiR-193a-3p介导NEAT1对神经细胞损伤的作用。4、抑制NEAT1调节miR-193a-3p以增加MMP14并减轻神经元细胞损伤。5、抑制NEAT1减轻脑卒中所致的体内损伤。进而得出结论：LncRNA NEAT1可竞争性结合miR-193a-3p调节MMP14表达从而在CIRI神经元损伤机制中起重要作用，为NEAT1成为缺血性中风新的诊断和治疗靶点提供理论和实验依据。