Homocysteine Affect Apoptosis Of Ischemic H9c2 Cell Line By Modulating IL-6/STAT3 Signal Pathway

Background: Myocardial Infarction(MI)is an ischemic heart disease that seriously threatens our lives.A large number of studies have demonstrated that inflammation induces cell necrosis,autophagy and/or apoptosis as one of its possible pathogenesis.The IL-6/STAT3 signaling pathway is an important inflammatory response pathway,and the role of STAT3 expression changes in myocardial infarction is still controversial.Homocysteine(Hcy)is one of the risk factors for cardiovascular and cerebrovascular diseases.The effects of high homocysteine and IL-6/STAT3 signaling pathway and myocardial ischemia have not been reported.Object: This study was to investigate the effect of Hcy on the expression of P-STAT3,Caspase-3 and IL-6 in H9c2 cell line and its effect on cell morphology in ischemic environment.Method: In this experiment,H9c2 rat cardiomyocyte cell line was cultured in 0% FBS medium,and different concentrations of Hcy were added in the logarithmic growth phase for different time.Western blotting,immunofluorescence staining and other methods were used.The expression of P-STAT3 and Caspase-3 in each group was detected.Then,Raloxifene was treated with Hcy was applied to the above cell line,and the expression of P-STAT3,Caspase-3 and IL-6 in each group was detected by qRT-PCR and the same method as above.Result: The results of Western Blot showed that: under the condition of 0% FBS,the expression of P-STAT3 and Caspase-3 increased with time after 0,1,2,4,6 and 8 h in 6 mM H9c2 cell line.At 6h,the expression of both was the strongest;2.0% FBS,different concentrations(0,1,2,4,6,8,mM)Hcy intervention in H9c2 cell line 6 hours after P-STAT3,Caspase-The expression level of 3 also increased with time and then decreased.The expression of P-STAT3 was the strongest at 6 mM.Under the condition of 0% FBS,Hcy increased the expression of P-STAT3 and Caspase-3.Raloxifene can be used.Decreased P-STAT3 expression,and not related to Hcy,but only decreased Hcy-induced Caspase-3 expression.The PCR results showed that Raloxifene could reduce the high expression of IL-6 induced by Hcy in H9c2 cell line under 0% FBS condition.The results of DHE staining showed that Hcy induced the increase of ROS expression in H9c2 cell line under 0% FBS condition,and Raloxifene pretreatment could attenuate this effect.The cell state under microscopy showed that under the condition of 0% FBS,the cells of H9c2 cells were obviously shrinkage and deformation,and the pretreatment of Raloxifene was beneficial to maintain cell morphology.Conclusion: This study preliminarily confirmed that under ischemic Hcy can further increase the expression of P-STAT3 in H9c2 cell line.Raloxifene partially inhibits the expression of P-STAT3,reduces apoptosis,and protects cell morphology.