Endurance exercise elicits temporal and sexual dimorphic multi-omics remodeling of liver metabolism revealed by MoTrPAC

The mechanisms by which exercise modulates liver metabolism are poorly understood. Leveraging data from molecular transducers of physical activity consortium (MoTrPAC), we analyzed liver adaptations across 1, 2, 4, and 8 weeks of exercise in male and female rats using multi-omics approaches. Female livers displayed a progressive increase in oxidative phosphorylation (OXPHOS) protein complexes, while male livers showed an increased acetylation of OXPHOS, tricarboxylic acid cycle, and fatty acid oxidation enzymes. Mechanistic examination revealed that these sex-specific acetylation events are partially mediated by carnitine acetyltransferase. Exercise enhanced liver cholesterol and bile acid synthesis, reducing liver lipid metabolites in males after 8 weeks of exercise. Male rats had higher fecal cholesterol and cholic acid levels, indicating a sex-specific mechanism of lipid excretion with exercise. Eight weeks of training reduced markers related to hepatic stellate cell activation and fibrosis in both sexes. This study highlights the sexual dimorphic and temporal molecular signatures by which exercise modulates liver metabolism to provide hepatoprotective effects.