抑制miR-186表达可减轻缺氧状态下血管内皮细胞线粒体的损伤

Inhibiting miR-186 expression alleviates mitochondrial damage in hypoxic human umbilical vein endothelial cells

目的探讨抑制miR-186表达对血管内皮细胞缺氧诱导因子-1α表达的影响和缺氧状态下线粒体功能的影响。方法构建人脐静脉内皮细胞缺氧培养模型,检测正常培养组与缺氧培养6 h组人脐静脉内皮细胞(HUVECs)miR-186表达量。干扰组HUVECs细胞转染miR-186-inhibit 48 h,干扰miR-186表达,对照组转染对照inhibit。检测miR-186的表达以确定干扰效果,干扰成功后缺氧培养6 h后观测实验组和对照组电镜下线粒体结构。干扰miR-186表达后检测缺氧诱导因子-1α的mRNA和蛋白表达。结果缺氧培养6 h的HUVECs细胞中miR-18表达轻度上升(P=0.0188)。转染miR-186inhibit 48 h可干扰miR-18670%~80%的表达,干扰miR-186表达促进缺氧诱导因子-1α的mRNA和蛋白表达。干扰组缺氧培养6 h,电镜下线粒体损伤明显减轻(P=0.00297)。结论干扰miR-186通过促进HIF-α上调,改善线粒体损伤,保护血管内皮细胞。靶向干扰miR-186可能有助于失血性休克的治疗。

Objective To investigate the effect of miR-186 inhibition on the expression of hypoxia-inducible factor-1α(HIF-α)and mitochondrial function in hypoxic vascular endothelial cells. Methods Human umbilical vein endothelial cells(HUVECs)cultured in routine or hypoxic conditions for 6 h were examined for the expression of miR-186. A miR-186 inhibitor was transfected in the HUVECs, and the cells were subsequently cultured in hypoxic condition for 6 h to observe the changes in the mitochondrial structure under an electron microscope. The changes in the mRNA and protein expressions of HIF-1α in response to miR-186 interference were tested using real-time fluorescent quantitative PCR and Western blotting. Results The expression of miR-18 was mildly increased in HUVECs after hypoxic exposure for 6 h(P=0.0188). Interference of miR-186 expression obviously promoted the mRNA and protein expressions of HIF-1α in HUVECs. In hypoxic conditions, miR-186 interference significantly reduced mitochondrial damage in HUVECs as observed under electron microscope(P=0.0297).Conclusion Inhibition of miR-186 protects vascular endothelial cells against hypoxic injuries by promoting HIF-α expression to lessen mitochondrial damage, suggesting the possibility of targeted miR-186 interference for treatment of hemorrhagic shock.