The Mechanism Of Astragaloside Ⅳ Protects Cardiomyocytes Against Anoxia/Reoxygenation Injury By Mediating 14-3-3η

Objective:Astragaloside IV(As-IV)is a small molecular active triterpenoid saponins component of Huang Qi,at present,which has been shown to protect many cardiovascular diseases.The major aim is to study the mechanism of As-IV against anoxia/reoxygenation(A/R)injury and further clarify whether the protective effect of As-IV against A/R injury mainly mediated by 14-3-3η protein.Method: In this study,rat H9c2 cardiomyocytes were used as experimental vectors,and I/R model in vivo were replicated by cardiomyocytes A/R model in vitro.The experimental was randomly divided into 7 groups,each group repeated 4 times:(1)Control group;(2)A/R group;(3)25μM AS-IV+A/R group;(4)50μM AS-IV+A/R group;(5)100μM AS-IV+A/R group;(6)50μM As-IV+AD14-3-3ηRNAi+A/R group;(7)50μM As-IV+ADscrRNAi+A/R group.The cell viability was monitored by MTS assay.The lactate dehydrogenase(LDH)was detected by Enzyme-linked immunosorbent assay.The 14-3-3η protein expression was measured by western blotting assay.Mitochondria membrane potential(Δψm)was measured by the JC-1 staining.The level of intracellular ROS was assayed by DCFH-DA.Cardiomyocyte apoptosis was detected by annexin V-FITC/PI double staining.Results: 1.Compared to A/R group,As-IV pretreatment rat H9c2 cardiomyocytes decreased LDH release and LDH activity(P<0.05)and increased the cell viability(P<0.05).2.The result of western blotting showed that 50μM As-IV pretreatment rat H9c2 cardiomyocytes up-regulated the expression of 14-3-3η protein(P<0.05).3.The result of flow detection showed that 50μM As-IV pretreatment rat H9c2 cardiomyocytes reduced intracellular ROS level,the loss of Δψm,cardiomyocyte apoptosis(P<0.01).4.AD 14-3-3ηRNAi abrogated or weakened the above protective effect of As-IV subjected to A/R injury.Conclusion: Astragaloside IV can up-regulate the expression of 14-3-3η protein,mediated by 14-3-3η,and play a protective role against myocardial A/R injury.