Department of Neurology, the Third Hospital of Xiamen, Xiamen, Fujian, China.
Eur Rev Med Pharmacol Sci. 2018 Jan;22(2):498-505. doi: 10.26355/eurrev_201801_14201.
The apoptosis of vascular endothelial cells (VEC) is related to ischemic stroke. Phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT/PKB) signaling pathway can upregulate Bcl-2 expression, reduce reactive oxygen species (ROS) production, and induce apoptosis. The level of miR-124 was significantly increased after cerebral ischemia. This study aimed to investigate the role of miR-124 in regulating PI3K expression, brain VEC apoptosis, and ROS production.
The expressions of miR-124, PI3K, p-AKT, and Bcl-2 in brain VEC of rats from the sham group and middle cerebral artery occlusion (MCAO) group were tested. Bioinformatics analysis showed the complementary binding site between miR-124 and PI3K mRNA. ROS content and cell apoptosis were detected by flow cytometry. Rat brain VEC were cultured in vitro and treated by oxygen-glucose deprivation (OGD) for 6 h. VECs were divided into four groups, including miR-NC, miR-124 inhibitor, pIRES2-blank, and pIRES2-PI3K groups, and were further treated by OGD.
MiR-124 expression, ROS content, and cell apoptosis were markedly increased, whereas the levels of PI3K, p-AKT, and Bcl-2 were markedly reduced in rat VECs from MCAO group compared with that in the sham group. OGD treatment significantly induced VECs apoptosis, upregulated miR-124 expression and ROS content, and down-regulated the levels of PI3K, p-AKT, and Bcl-2. MiR-124 inhibitor or transfection of pIRES2-PI3K plasmid apparently enhanced PI3K, p-AKT, and Bcl-2 expressions, alleviated cell apoptosis and decreased ROS content in VECs induced by OGD.
Our data demonstrated that miR-124 induced the apoptosis of brain vascular endothelial cells via the down-regulation of PI3K/AKT signaling pathway and promotion of ROS production.
血管内皮细胞（VEC）的凋亡与缺血性中风有关。磷酸肌醇-3 激酶（PI3K）/蛋白激酶 B（AKT/PKB）信号通路可上调 Bcl-2 表达，减少活性氧（ROS）产生，并诱导细胞凋亡。脑缺血后 miR-124 的水平显著升高。本研究旨在探讨 miR-124 调节 PI3K 表达、脑 VEC 凋亡和 ROS 产生的作用。
检测假手术组和大脑中动脉闭塞（MCAO）组大鼠脑 VEC 中 miR-124、PI3K、p-AKT 和 Bcl-2 的表达。生物信息学分析显示 miR-124 与 PI3K mRNA 之间存在互补结合位点。通过流式细胞术检测 ROS 含量和细胞凋亡。体外培养大鼠脑 VEC，用氧葡萄糖剥夺（OGD）处理 6 h。将 VEC 分为 miR-NC、miR-124 抑制剂、pIRES2-空白和 pIRES2-PI3K 组，进一步用 OGD 处理。
与假手术组相比，MCAO 组大鼠 VEC 中 miR-124 表达、ROS 含量和细胞凋亡明显增加，而 PI3K、p-AKT 和 Bcl-2 水平明显降低。OGD 处理显著诱导 VEC 凋亡，上调 miR-124 表达和 ROS 含量，下调 PI3K、p-AKT 和 Bcl-2 水平。miR-124 抑制剂或 pIRES2-PI3K 质粒转染明显增强了 OGD 诱导的 VEC 中 PI3K、p-AKT 和 Bcl-2 的表达，减轻了细胞凋亡，降低了 ROS 含量。
我们的数据表明，miR-124 通过下调 PI3K/AKT 信号通路和促进 ROS 产生诱导脑血管内皮细胞凋亡。
