Effect And Mechanism Of SH2B1 On Glucose Metabolism In Ang Ⅱ Induced Cardiomyocyte Hypertrophy

Background: The occurrence and development of pathological cardiac hypertrophy involves the metabolic reprogramming phenomenon of enhanced glucose metabolism and weakened fatty acid metabolism.Studies have shown that homology 2B binding protein 1（SH2B1）is very important to control energy balance,especially glucose homeostasis.Whether changing the expression of SH2B1 can reverse the change of energy utilization preference in the process of cardiac hypertrophy,especially glycolytic flux,is not clear.Objective: The purpose of this study is to explore the specific mechanism of SH2B1 aggravating Ang Ⅱ induced pathological cardiac hypertrophy by changing glycolytic flux.Methods: Firstly,the isolated and cultured neonatal rat cardiomyocytes were randomly divided into control group;Ang II group and control group did not do any treatment,and the latter was added with 1 μ M cardiomyocyte hypertrophy promoting factor Ang II,n = 3 in each group.The m RNA levels of cardiac hypertrophy markers ANP,BNP,Mhy6 and Myh7 were detected by fluorescence quantitative PCR,and the expression levels of SH2B1,glucose transporter 4（GLUT4）,glucose-6-phosphate dehydrogenase（G6PD）and signal pathway AMPK were detected by Western blot.Then,small interfering RNA（si RNA）was used to silence SH2B1 gene and adenovirus overexpressed SH2B1 gene,and neonatal rat cardiomyocytes were divided into si Neg group（control group）;si Neg + Ang II group;si SH2B1 group: si SH2B1 + Ang II group and Ad NC group（control group）,Ad NC +Ang II group,Ad SH2B1 group,Ad SH2B1 + Ang II group,The control group was transfected with empty small interfering RNA or blank adenovirus,and the other groups were given corresponding intervention measures,n = 3 in each group;The changes of cardiomyocyte area,cardiac hypertrophy markers,glucose metabolism related proteins such as GLUT4、G6PDand AMPK signaling pathway were detected.Then,neonatal rat cardiomyocytes were treated with AMPK inhibitor compound C to detect the effect of AMPK signaling pathway on glucose metabolism related proteins.Neonatal rat cardiomyocytes were divided into control group,Ang II group and Ang II+ compound C group,that is,cardiomyocytes were stimulated by Ang II to form cardiomyocyte hypertrophy model,AMPK inhibitor intervened while stimulated by Ang II,and glucose metabolism related proteins GLUT4 and G6 PD were detected by Western blot.Results: Compared with cells without Ang II,the relative expression of SH2B1 protein increased after Ang II induced cardiomyocyte hypertrophy（n = 3,P < 0.05）,and the levels of GLUT4,G6 PD and phosphorylated AMPK protein also increased;In addition,compared with Ang II + si Neg group,the indexes of cardiac hypertrophy in Ang II + si SH2B1 group,namely cardiomyocyte area,ANP,BNP and Myh7 decreased,Myh6 increased,GLUT4 and G6 PD decreased（n = 3,P < 0.05）,and AMPK signal pathway was inhibited.When overexpressing SH2B1,compared with Ang II + Ad NC group,the indexes of cardiac hypertrophy in Ang II + Ad SH2B1 group increased,and the activation of GLUT4,G6 PD and AMPK was more obvious;At the same time,after using AMPK inhibitor,the activity of glucose metabolism inhibited,that is,the expression of glucose metabolism related proteins GLUT4 and G6 PD decreased（n = 3,P < 0.05）Conclusion: SH2B1 can aggravate Ang Ⅱ induced cardiomyocyte hypertrophy by promoting Glycometabolism,which may be related to activated AMPK signaling pathway.