上调miR-21-5p对阿霉素诱导的心肌细胞增殖、凋亡的影响及其机制研究

Effect and mechanism of up-regulation of miR-21-5p on doxorubicin-induced cardiomyocyte proliferation and apoptosis

目的:探讨上调miR-21-5p表达对阿霉素(DOX)诱导的心肌细胞增殖和凋亡的影响及其机制研究。方法:将心肌细胞H9C2分成control组(常规培养的对照细胞)、DOX组(用含1μmol/L DOX的细胞培养液培养)、NC agomir处理组(DOX+NC ago组)、miR-21-5p agomir处理组(DOX+miR-21-5p ago组)、NC antagomir处理组(DOX+NC anta组)、miR-21-5p antagomir处理组(DOX+miR-21-5p anta组)。实时荧光定量PCR法测定miR-21-5p的表达,MTT法测定细胞增殖,流式细胞术测定细胞凋亡,western blotting测定细胞中C-Caspase-3、β-catenin、c-Myc蛋白表达。结果:与control组相比,DOX组中miR-21-5p水平降低,细胞增殖活性降低,细胞凋亡和C-Caspase-3蛋白表达水平升高,β-catenin、c-Myc蛋白表达水平下降(P<0.05)。与DOX+NC ago组比较,DOX+miR-21-5p ago组中miR-21-5p水平升高,细胞增殖活性上升,细胞凋亡和C-Caspase-3蛋白表达水平降低,β-catenin、c-Myc蛋白表达水平上升(P<0.05)。结论:上调miR-21-5p可促进DOX诱导的心肌细胞增殖,并通过Wnt/β-catenin信号通路抑制DOX诱导的心肌细胞凋亡,从而改善DOX诱导的心肌毒性作用。

Objective:To investigate the effect and mechanism of up-regulation of miR-21-5p on doxorubicin(DOX)-induced cardiomyocyte proliferation and apoptosis.Methods:Cardiomyocytes H9C2 were divided into control group(conventional-cultured control cells),DOX group(cultured with 1μM DOX),NC agomir group(DOX+NC ago group),miR-21-5p agomir group(DOX+miR-21-5p ago group),NC antagomir treatment group(DOX+NC anta group),and miR-21-5p antagomir treatment group(DOX+miR-21-5p anta group).The expression of miR-21-5p was detected by reverse transcription-quantitative polymerase chain reaction(RT-qPCR),cell proliferation was detected by MTT,cell apoptosis was detected by flow cytometry,and the protein expression of C-Caspase-3,β-catenin and c-Myc was detected by western blotting.Results:Compared with the control group,the level of miR-21-5p and cell proliferation activity were decreased,apoptosis and C-Caspase-3 protein expres sion levels were increased,andβ-catenin and c-Myc protein expression levels were decreased in the DOX group(P<0.05).Compared with the DOX+NC ago group,the level of miR-21-5p in the DOX+miR-21-5p ago group was increased,cell proliferation activity was increased,apoptosis and C-Caspase-3 protein expression levels were decreased,andβ-catenin and c-Myc protein expression levels were increased(P<0.05).Conclusion:Up-regulation of miR-21-5p promotes DOX-induced cardiomyocyte proliferation and inhibits DOX-induced cardiomyocyte apoptosis through Wnt/β-catenin signaling pathway,thereby ameliorating DOX-induced cardiotoxicity.