Effect of lifelong resveratrol supplementation and exercise training on skeletal muscle oxidative capacity in aging mice; impact of PGC-1α

The present study tested the hypothesis that lifelong resveratrol (RSV) supplementation counteracts an age-associated decrease in skeletal muscle oxidative capacity through peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α and that RSV combined with lifelong exercise training (EX) exerts additive effects through PGC-1α in mice. 3month old PGC-1α whole body knockout (KO) and wild type (WT) littermate mice were placed in cages with or without running wheel and fed either standard chow or standard chow with RSV supplementation (4g/kg food) for 12months. Young (3months of age), sedentary mice on standard chow served as young controls. A graded running performance test and a glucose tolerance test were performed 2 and 1week, respectively, before euthanization where quadriceps and extensor digitorum longus (EDL) muscles were removed. In PGC-1α KO mice, quadriceps citrate synthase (CS) activity, mitochondrial (mt)DNA content as well as pyruvate dehydrogenase (PDH)-E1α, cytochrome (Cyt) c and vascular endothelial growth factor (VEGF) protein content were 20–75% lower and, EDL capillary-to-fiber (C:F) ratio was 15–30% lower than in WT mice. RSV and/or EX had no effect on the C:F ratio in EDL. CS activity (P=0.063) and mtDNA content (P=0.013) decreased with age in WT mice, and CS activity, mtDNA content, PDH-E1α protein and VEGF protein increased ~1.5–1.8-fold with lifelong EX in WT, but not in PGC-1α KO mice, while RSV alone had no significant effect on these proteins. Lifelong EX increased activity/content of oxidative proteins, mtDNA and angiogenic proteins in skeletal muscle through PGC-1α, while RSV supplementation alone had no effect. Combining lifelong EX and RSV supplementation had no additional effect on skeletal muscle oxidative and angiogenic proteins. •Lifelong training increased mitochondrial DNA content and oxidative capacity.•Lifelong resveratrol intake had no effect on skeletal muscle oxidative capacity.•Combining training and resveratrol intake had no additional effect on oxidative capacity.•Effects of lifelong training in oxidative capacity of aging mice required PGC-1α.