The Role Of Autophagy In The H9c2 Cardiac Myocyte Hypertrophy Induced By Isoprenaline And Intervention Effects Of Sinomenine

Objective: To investigate the role of autophagy in H9c2 cardiac hypertrophy(CH)induced by Isoprenaline(Iso),and study the intervention effects of Sinomenine(Sin)on CH induced by Iso.Methods:(1)MTT assay was used to measure the effects of Sin on survival of H9c2 cardiomyocytes,and to determine the security concentration of Sin.(2)Crystal violet staining was used to observe cell morphology under inverted microscope,and to measure the area of cardiomyocytes by image-pro plus 6.0 software in each group.(3)To determine the total protein content in each group by BCA method.(4)To detect the concentration of IL-6 in extracellular fluid by Enzyme-linked immunosorbent assay(ELISA).(5)To detect autophagy by fusion protein of mCherry-GFP-LC3 B double fluorescence system.(6)To detect theprotein expression of ANP?LC3B(LC3??LC3?)and Phospho-Akt(Thr308)by Western blot.Results:(1)Safety margin of Sin on H9c2 myocardial cells was within the 300?mol/L concentration range.(2)surface area of H9c2 myocardial cells in the model group is significantly higher than that of the normal group(***P<0.001),and compared with the Iso model group,myocardial cells of Sin groups become wider,surface area has decreased(###P<0.001).(3)Total protein content of Iso model group is increased significantly compared to the normal group(*P<0.05),which are decreased in the Sin groups compared with model group.(4)The concentration of IL-6 in the extracelluar fluid of the Iso model group is much higher than that of the noraml group(*P<0.05).Compared with the Iso model group,Sin groups significantly reduced IL-6 levels.(5)Red and yellow spots on the Iso model group are significantly less than that of the normal group(*P<0.05),to compared with the Iso model group,Sin groups are increased.(6)Expressions of ANP and Phospho-Akt(Thr308)in the Iso model group are up-regulated compared with the normal group,and the ratio of LC3?/? is increased.ANP and Phospho-Akt(Thr308)protein in the Sin groups are decreased compared with the Iso model group,the ratio LC3?/?of low and midle groups is also has declined.Conclusion: Autophagy is inhibited in CH induced by Iso,and through decreasing the release of IL-6,Sin is probably to inhibitphosphorylation of AktT308 for enhancing autophagy to improve myocardial cell hypertrophy.