Obesity is associated with an increased risk of developing cardiovascular disease (CVD), with limited alterations in cardiac genomic characteristics known. Cardiac transcriptome analysis was conducted to profile gene signatures in high-fat diet (HFD)-induced obese mice. A total of 184 differentially expressed genes (DEGs) were identified between groups. Based on the gene ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs, the critical role of closely interlocked glucose metabolism was determined in HFD-induced cardiac remodeling DEGs, including Nr4a1, Fgf21, Slc2a3, Pck1, Gck, Hmgcs2, and Bpgm. Subsequently, the expression levels of these DEGs were evaluated in both the myocardium and palmitic acid (PA)-stimulated H9c2 cardiomyocytes using qPCR. Nr4a1 was highlighted according to its overexpression resulting from the HFD. Additionally, inhibition of Nr4a1 by siRNA reversed the PA-induced altered expression of glucose metabolism-related DEGs and hexokinase 2 (HK2), the rate-limiting enzyme in glycolysis, thus indicating that Nr4a1 could modulate glucose metabolism homeostasis by regulating the expression of key enzymes in glycolysis, which may subsequently influence cardiac function in obesity. Overall, we provide a comprehensive understanding of the myocardium transcript molecular framework influenced by HFD and propose Nr4a1 as a key glucose metabolism target in obesity-induced CVD.
Dendritic cells (DCs) play a crucial role in immune protection against myocardial infarction (MI). Through multiple experimental methods including bioinformatics, qPCR, Western blotting, immunofluorescence, MTT assays, echocardiography, TTC staining, and flow cytometry, this study found that metabolism was demonstrated to be markedly altered under oxygen–glucose deprivation (OGD) conditions in DCs. Pyruvate kinase M2 (PKM2) is a key protein in metabolism, and PKM2 was upregulated under OGD conditions in DCs. Trichostatin A (TSA) alleviated the OGD-induced cellular damage in DCs. Furthermore, TSA was shown to modulate DCs’ function by enhancing glycolysis while suppressing fatty acid synthesis and oxidation pathways. The metabolic changes caused by TSA and OGD were mechanistically mediated by PKM2. Mechanistically, PKM2 modulates glucose and lipid metabolism via its dimer formation. These results deepen our understanding of the interplay among TSA, glucose and lipid metabolism and DC functions in MI.