Oncometabolism Drives Autophagy Activation in Skeletal Muscle

Metabolic rewiring is a well-established feature of muscle cells and a hallmark of cancer. In isocitrate dehydrogenase 1 and 2 mutant tumors, increased production of the oncometabolite D-2-hydroxyglutarate (D2-HG) is associated with myopathy. The connection between metabolic changes and proteomic remodeling in skeletal muscle remains poorly understood. We demonstrate that D2-HG impairs NAD+ redox homeostasis in myocytes, causing activation of autophagy via de-acetylation of microtubule-associated protein 1 light chain 3-II (LC3-II) by the nuclear deacetylase Sirt1. We integrated multi-omics data from mice treated with D2-HG and demonstrate that autophagy activation leads to skeletal muscle atrophy and sex-dependent metabolic and proteomic remodeling. We also characterized protein and metabolite interactions linking energy-substrate metabolism with chromatin organization and autophagy regulation. Collectively, our multi-omics approach exposes mechanisms by which the oncometabolite D2-HG induces metabolic and proteomic remodeling in skeletal muscle, and provides a conceptual framework for identifying potential therapeutic targets in cachexia.