The Damage Mechanism Of H9c2 Cardiomyocytes Induced By High Glucose And The Effect Of Salidroside Intervention

BackgrouedDiabetic cardiomyopathy（DCM）is a cardiomyopathy caused by glucose metabolism disorder with cardiac structure and dysfunction as the main pathological changes,which is independent of hypertension,coronary heart disease and cardiac valve disease.The specific pathogenesis of DCM is very complex,mainly involving myocardial metabolic disorders,oxidative stress,inflammatory response,myocardial fibrosis,mitophagy and so on.It is reported that mitophagy mediated by Pink1 /Pakrin pathway plays an important role in the pathogenesis of DCM.Salidroside（SAL）is the main active component of Rhodiola in traditional Chinese medicine.SAL can reduce insulin resistance and regulate mitochondrial autophagy.However,it is not clear whether SAL can interfere with the protective effect of high glucose-induced cardiomyocytes through the Pink1 / Pakrin signaling pathway.Objective.To explore the effect of salidroside on promoting mitophagy to reduce the damage of H9c2 cardiomyocytes induced by high glucose,and to provide modern molecular biological evidence for SAL in the treatment of DCM.Methods1.The H9c2 cardiomyocytes injury model induced by high glucose was established : H9c2 cells were cultured,and H9c2 cells were stimulated with different concentrations of high glucose solution（30,60,120,240 and 360 mmol / L）for 24 h,respectively.The cell viability of each group was detected by MTT method.2.To clarify the effect of salidroside on H9c2 cardiomyocytes injury induced by high glucose : SAL at different concentrations was used to pretreat H9c2 cardiomyocytes for 24 h,and the viability of cardiomyocytes in each group was detected by MTT method to determine the optimal drug concentration.3.To explore the mechanism of salidroside intervention on H9c2 myocardial cell injury induced by high glucose : DCFH-DA fluorescent probe was used to detect the generation of reactive oxygen species（ROS）in each group;TMRE fluorescent probe was used to detect the change of mitochondrial membrane potential;luciferase assay was used to detect the generation of ATP in each group;Western blot was used to detect the expression of P62,Pink1,Pakrin and LC3 proteins in each group.Results1.With the increase in the concentration of high glucose solution,the activity of H9c2 gradually decreased.At 240 mmol / L,the activity of cardiomyocytes was about50 % of that of the control group.Therefore,240 mmol / L high glucose solution was selected to explore the effect and mechanism of salidroside on high glucose-induced H9c2 cardiomyocytes injury.2.After pretreatment with SAL for 24 h,the cell viability increased with the increase of SAL concentration from 100μmol / L to 400μmol / L.Especially at 400μmol / L,salidroside significantly improved H9c2 cardiomyocytes injury induced by high glucose.3.After H9c2 was induced by high glucose,the production of intracellular reactive oxygen species increased,the mitochondrial membrane potential line decreased,and ATP production decreased,which could be reversed after SAL intervention.The expression of P62 protein in high glucose group increased,and the expression of Pink1,Pakrin and LC3 protein decreased.The expression of P62 protein in SAL group decreased,and the expression of Pink1,Pakrin and LC3 protein increased,especially at 400 μmol / L,the difference was statistically significant.ConclusionSalidroside alleviates high glucose-induced H9c2 myocardial cell injury by regulating P62 / Pink1 / Parkin / LC3 signaling pathway,reducing reactive oxygen species production,improving mitochondrial membrane potential and promoting ATP production.