miR-221对高糖诱导的人视网膜血管内皮细胞凋亡的作用机制

Molecular mechanism of miR-221 promoting apoptosis of human retinal vascular endothelial cells induced by high glucose by regulating p53/MDM2 signaling pathway

目的:研究miR-221对高糖诱导的人视网膜血管内皮细胞(HRCECs)凋亡的影响,并探讨其作用机制。方法:用葡萄糖30mmol/L处理HRCECs 48h建立高糖诱导的HRCECs细胞;将HG+miR-NC组(转染miR-NC)、HG+miR-221组(转染miR-221 mimics)、HG+anti-miR-NC组(转染anti-miR-NC)、HG+anti-miR-221组(转染anti-miR-221)、HG+miR-221+pcDNA 3.1组(共转染miR-221 mimics和pcDNA 3.1)、HG+miR-221+pcDNA 3.1-MDM2组(共转染miR-221 mimics和pcDNA 3.1-MDM2),用脂质体法转染至HRCECs细胞,再进行高糖处理;qRT-PCR法检测细胞中miR-221、p53、MDM2的表达;Western blot检测细胞中p53、MDM2的蛋白表达;流式细胞术检测细胞的凋亡。结果:与NG组相比,高糖诱导的HRCECs细胞中miR-221、p53的表达显著升高,MDM2的表达显著降低,细胞凋亡率显著升高;过表达miR-221可使高糖诱导的HRCECs细胞的凋亡率升高更明显,抑制miR-221可下调高糖诱导的HRCECs细胞的凋亡并下调p53,上调MDM2;过表达MDM2则可逆转抑制miR-221对高糖诱导的HRCECs细胞的抗凋亡作用及对p53、MDM2的调控。结论:miR-221可促进高糖诱导的人视网膜血管内皮细胞凋亡,其机制与p53/MDM2信号通路有关。

AIM:To study the effect of miR-221 on apoptosis of high glucose-induced human retinal vascular endothelial cells and to explore its mechanism.METHODS:High-glucose-induced HRCECs were established by treatment of HRCECs cells with glucose at 30mmol/L for 48h;HG+miR-NC group(transfected miR-NC),HG+miR-221 group(transfected miR-221 mimics),HG+anti-miR-NC group(transfected anti-miR-NC),HG+anti-miR-221 group(transfected anti-miR-221),HG+miR-221+pcDNA 3.1 group(co-transfected miR-221 mimics and pcDNA 3.1),HG+miR-221+pcDNA 3.1-MDM2 group(co-transfected miR-221 mimics and pcDNA 3.1-MDM2),transfected into HRCECs cells by liposome method,and then treated with high glucose;qRT-PCR method for detection the expression of miR-221,p53 and MDM2;the protein expression of p53 and MDM2 were detected by Western blot.The apoptosis of cells was detected by flow cytometry.RESULTS:Compared with NG group,the expression of miR-221 and p53 was significantly increased,the expression of MDM2 was significantly decreased,and the apoptosis rate was significantly increased in high glucose-induced HRCECs.Overexpression of miR-221 induced apoptosis of high glucose-induced HRCECs cells is more obvious.Inhibition of miR-221 can down-regulate the apoptosis of high glucose-induced HRCECs and down-regulate p53,up-regulate MDM2;overexpression of MDM2 can reverse the inhibition by miR-221 anti-apoptotic effect of cells and regulation of p53 and MDM2 of high-glucose-induced HRCECs.CONCLUSION:miR-221 can promote the apoptosis of high-glucose-induced human retinal vascular endothelial cells,and its mechanism is related to p53/MDM2 signaling pathway.