丹参酮ⅡA通过miR-155-5p激活SIRT1-AMPK通路改善H9c2心肌细胞缺血/再灌注损伤OACSCDCSTPCD

Objective:To explore the mechanism of Tanshinone ⅡA(TⅡA)in improving ischemia/reperfusion(I/R)injury of H9c2 cardiomyocytes by activating Sirtuin 1(SIRT1)-adenosine 5'-monophosphateactivated protein kinase(AMPK)pathway through miR-155-5p.Methods:H9c2 cells were cultured in vitro and I/R damage model was established.After modeling,H9c2 cells were randomly divided into model group,TⅡA group,TⅡA+miR-NC group,TⅡA+miR-155-5p mimics group,10 µmol/L TⅡA was added for intervention after transfection,and the H9c2 cells supplemented with DMSO were used as control group.qRT-PCR was used to detect expression level of miR-155-5p;MTT method was used to analyze cell proliferation ability;flow cytometry was used to evaluate cell apoptosis;ELISA was used to determine the levels of TNF-α,IL-4,IL-10,IL-17,lactate dehydrogenase(LDH),malo-ndialdehyde(MDA)and superoxide dismutase(SOD);Western blot was used to detect relative expressions of SIRT1,AMPK and p-AMPK proteins.Results:Compared with control group,expression of miR-155-5p in model group was increased,cell viability was decreased,apoptosis rate and expressions of TNF-α,IL-17,LDH and MDA were increased,while expressions of IL-4,IL-10,SOD,SIRT1 and p-AMPK were decreased(P<0.05);compared with model group,expression of miR-155-5p in TⅡA group was reduced,cell viability was increased,apoptosis rate and expressions of TNF-α,IL-17,LDH and MDA were decreased,while expressions of IL-4,IL-10,SOD,SIRT1 and p-AMPK were increased(P<0.05);compared with TⅡA group and TⅡA+miR-NC group,expression of miR-155-5p in TⅡA+miR-155-5p mimics group was increased,cell viability was decreased,apoptosis rate and expressions of TNF-α,IL-17,LDH and MDA were increased,while expressions of IL-4,IL-10,SOD,SIRT1 and p-AMPK were decreased(P<0.05).Conclusion:TⅡA can improve I/R injury of H9c2 cardiomyocytes by down-regulating miR-155-5p,and its mechanism may be related to the activation of SIRT1-AMPK pathway.