β-Hydroxybutyrylation Links Ketone Metabolism to Mitochondrial Remodeling in Diabetic Cardiomyopathy

We performed a multiomics study to better understand dysfunctions in diabetic cardiomyopathy (DbCM) and specifically identify links between lysine β-hydroxybutyrylation (Kbhb), a ketone body-derived, posttranslational modification, and cardiac dysfunction. DbCM cardiac tissue exhibited coordinated upregulations of fatty acid β-oxidation, ketone metabolism, and tricarboxylic acid cycle activity at the transcriptomic, proteomic, and metabolomic levels. Mitochondrial proteins showed that high Kbhb modification and modification of the Atp5f1a-K239 site were strongly correlated with high β-hydroxybutyrate and isocitric acid concentrations. This study identifies Kbhb modification of mitochondrial proteins as a potential mechanism linking ketone body availability to mitochondrial function in DbCM.