The regulatory effect of Ca2+/calmodulin dependent protein kinase II mediated by receptor interacting protein kinase 3 on necroptosis of hypertrophic cardiomyocytes

Receptor interacting protein kinase 3 (RIPK3) plays a crucial role in the signaling pathway of necroptosis and calcium/calmodulin dependent protein kinase II (CaMKII) is a novel substrate for RIPK3 induced necroptosis. The aim of this study is to investigate the regulation and mechanism of RIPK3 on AngII induced cardiomyocyte hypertrophy.AngII was used to stimulate myocardial cells for 72 hours, inducingcardiomyocytehypertrophy; Use RIPK3 inhibitor GSK872 to reduce RIPK3 expression.Detect indicators related to myocardial hypertrophy, cell damage, necroptosis,CaMKII activation and gene expression, oxidative stress, mitochondrial membrane potential, etc. After AngII stimulation of cardiomyocytes, the expression of hypertrophy markers ANP and BNP increased, LDH release increased, ATP levels decreased, splicing factors ASF and SC35 expression increased, CaMKII oxidation and phosphorylation levels increased, and CaMKII{delta} alternative splicing was disrupted. However, treatment with GSK872 can alleviate myocardial dysfunction, inhibit CaMKII activation, correct CaMKII{delta} variant splicing disorder and ultimately alleviating myocardial hypertrophy. In addition, pretreatment with RIPK3 can reduce the accumulation of reactive oxygen species (ROS) induced by AngII, decrease the activity of ASF and SC35, and restore mitochondrial membrane potential. RIPK3 inhibitor GSK872 can inhibit the activation of CaMKII, alleviate necroptosis and oxidative stress to alleviate myocardial hypertrophy. It has a protective effect on myocardial hypertrophy and is expected to become a new targeted drug for clinical treatment of dilated cardiomyopathy and heart failure.