MicroRNA-200c 对Ox-LDL 介导的 人主动脉内皮细胞损伤的影响

Effect of miR-200c on Ox-LDL-induced injury of human aortic endothelial cells

摘要:

目的 探讨microRNA-200c（miR-200c）在氧化低密度脂蛋白（Ox-LDL）损伤人主动脉内皮细胞 （HAEC）中的表达及其对细胞活力、凋亡的影响及相关机制。方法 采用qRT-PCR 检测Ox-LDL 损伤HAEC miR-200c 的表达水平；转染miR-200c inhibitor 抑制miR-200c 的表达后，分别运用MTT 和流式细胞术检测 细胞活力和细胞凋亡情况；Western blot 检测Slit2 蛋白表达水平；荧光素酶报告系统检测miR-200c 对Slit2 的 靶向调节。结果 Ox-LDL 呈浓度和时间模式刺激HAEC 中miR-200c 表达上调。抑制miR-200c 表达可上调 细胞活力，抑制Ox-LDL 诱发的细胞凋亡。抑制miR-200c 可上调Slit2 蛋白表达水平。双荧光素酶报告实验转 染In-miR-200c 的细胞内Slit2 相对荧光强度高于对照组。沉默Slit2 可部分逆转In-miR-200c 对细胞活力的促 进作用和对细胞凋亡的抑制作用。结论 miR-200c 在Ox-LDL 诱导的HAEC 表达上调，抑制miR-200c 的表达 可通过靶向作用于Slit2 抑制Ox-LDL 诱导的细胞凋亡。

Abstract:

Objective To investigate the expression and effect of miR-200c on cell survival and apoptosis in human aortic endothelial cells (HAECs) injured by oxidized low density lipoprotein (Ox-LDL). Methods The expression of miR-200c in Ox-LDL injured HAECs was detected by qRT-PCR. After transfection of miR-200c inhibitor, the cell viability and cell apoptosis were analyzed by MTT and flow cytometry respectively. Luciferase assay was performed to detect whether Slit2 was the direct target of miR-200c. Results miR-200c expression was up-regulated by Ox-LDL treatment in the HAECs in a time- and dose-dependent manner. miR-200c inhibition enhanced cell survival and inhibited cell apoptosis. Knockdown of miR-200c up-regulated Slit2 protein expression level. The transfection of miR-200C inhibitor significantly increased the relative luciferase intensity of Slit2. Furthermore, silencing of Slit2 partly reversed the effect of miR-200c inhibitor on cell survival and cell apoptosis. Conclusions miR-200c is up-regulated in Ox-LDL-treated HAECs, and miR-200c inhibition impedes Ox-LDLinduced apoptosis by targeting Slit2.