Comparative proteomic analysis of hearts from mice with high-fat diet-induced metabolic cardiomyopathy

In patients with obesity or type 2 diabetes, the accumulation of lipotoxic by-products in cardiomyocytes leads to apoptosis and contractile dysfunction, eventually resulting in metabolic cardiomyopathy (MC). However, the underlying mechanisms remain unclear. Inb this study, a comparative proteome analysis was conducted to evaluate the differentially expressed proteins (DEPs) in the hearts of normal mice on standard diet (control group) and of high-fat diet (HFD)-induced MC mice (HFD group). We identified 90 DEPs unique to the control group and 18 DEPs unique to the HFD group. In 90 DEPs unique to the control group, only 74 DEPs were annotated in the gene ontology (GO) database. These annotated DEPs are involved in 114 biological processes, 68 molecular functions, and 174 cellular components. In 18 DEPs unique to the HFD group, only 14 DEPs were annotated in the GO database. These annotated DEPs are involved in 24 biological processes, 22 molecular functions, and six cellular components. Protein levels of two fatty acid metabolism-related enzymes, carnitine palmitoyltransferase 1B (CPT1B) and acetyl-CoA acyltransferase 2 (ACAA2), in the hearts of the mice in control group and HFD group were analyzed by immunostaining and Western blot. The results showed that the protein levels of CPT1B and ACAA2 were elevated in hearts of the mice in HFD group, which were consistent with the proteomic analysis. Our results reveal the differentially expressed proteome related to the progression of MC, providing a series of potential therapeutic targets for MC.