血浆外泌体源性miR-29b-3p靶向IGF1对七氟醚后处理低氧/复氧心肌细胞损伤的作用

Effects of plasma exosome-derived miR-29b-3p on myocardial cell injury in hypoxia/reoxygenation after sevoflurane postconditioning via targeting IGF1

目的探讨心肌缺血再灌注损伤(MIRI)大鼠血浆外泌体源性miR-29b-3p靶向IGF1在七氟醚(SEV)后处理的低氧/复氧(H/R)心肌细胞中的作用。方法借助GEO数据库筛选在MIRI中差异表达的miRNAs,通过H/R处理心肌细胞以构建MIRI细胞模型。干预经SEV后处理的MIRI细胞模型中miR-29b-3p和IGF1的表达,随后通过MTT检测心肌细胞存活率,流式细胞术检测细胞凋亡,ELISA检测各组心肌细胞中炎性因子(IL-1β和TNF-α)的变化。结果与Normal组比较,miR-29b-3p在MIRI大鼠血浆外泌体中表达增强(P<0.05),miR-29b-3p和IGF1的靶向结合关系被证实(P<0.05)。SEV后处理后,H/R刺激的心肌细胞中miR-29b-3p的表达降低,而IGF1的表达升高(均P<0.05)。血浆外泌体中miR-29b-3p过表达可明显抑制SEV后处理的H/R细胞存活率,加重细胞凋亡和炎性反应,敲减miR-29b-3p则相反(均P<0.05)。挽救实验数据表明,过表达IGF1可部分逆转过表达miR-29b-3p对SEV后处理的H/R细胞损伤的影响(均P<0.05)。结论血浆外泌体源性miR-29b-3p靶向IGF1促进SEV后处理的H/R心肌细胞损伤。

Objective The purpose of this study was to investigate the effects of plasma exosome-derived miR-29b-3p in myocardial ischemia-reperfusion injury(MIRI)rats on hypoxia/reoxygenation(H/R)cardiomyocyte after sevoflurane(SEV)postconditioning through targeting IGF1.Methods The GEO database was used to screen differentially expressed miRNAs in MIRI,and cardiomyocytes were treated with H/R to construct a MIRI cell model.The expression of miR-29b-3p and IGF1 in the MIRI cell model post-treated with SEV was intervened,and then the survival rate of cardiomyocytes was detected by MTT,apoptosis was detected by flow cytometry,and inflammatory factors(IL-1βand TNF-α)in cardiomyocytes in each group were detected by ELISA.Results Compared with Normal group,the expression of miR-29b-3p in plasma exosomes of MIRI rats was enhanced(P<0.05),and the target-binding relationship between miR-29b-3p and IGF1 was confirmed(P<0.05).After SEV post-treatment,the expression of miR-29b-3p in H/R-stimulated cardiomyocytes decreased,while the expression of IGF1 increased(both P<0.05).Overexpression of miR-29b-3p in plasma exosomes could significantly inhibit the survival rate of H/R cells after SEV treatment,aggravate apoptosis and inflammatory response,while knockdown of miR-29b-3p showed a opposite effects(all P<0.05).The rescue experimental data showed that overexpression of IGF1 could partially reverse the effects of overexpression of miR-29b-3p on H/R cell injury after SEV treatment(all P<0.05).Conclusion Plasma exosome-derived miR-29b-3p promotes H/R cardiomyocyte injury after SEV treatment by targeting IGF1.