Oral quercetin supplementation hampers skeletal muscle adaptations in response to exercise training

• DOI: 10.1111/sms.12136
• Publication Date: 2013-10-14T05:14:42Z
• Authors: R. A. Casuso; E. J. Martínez‐López; N. B. Nordsborg; F. Hita‐Contreras; R. Martínez‐Romero; A. Cañuelo; A. Martínez‐Amat
• Keywords: Male; 0301 basic medicine; Superoxide Dismutase; Administration, Oral; Citrate (si)-Synthase; Catalase; Adaptation, Physiological; DNA, Mitochondrial; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Antioxidants; Quadriceps Muscle; Rats; Protein Carbonylation; 03 medical and health sciences; Sirtuin 1; Physical Conditioning, Animal; Animals; Quercetin; RNA, Messenger; Rats, Wistar; Transcription Factors

We aimed to test exercise‐induced adaptations on skeletal muscle when quercetin is supplemented. Four groups of rats were tested: quercetin sedentary, quercetin exercised, placebo sedentary, and placebo exercised. Treadmill exercise training took place 5 days a week for 6 weeks. Quercetin groups were supplemented with quercetin, via gavage, on alternate days throughout the experimental period. Sirtuin 1 (SIRT1), peroxisome proliferator‐activated receptor γ coactivator‐1αmRNAlevels, mitochondrialDNA(mtDNA) content, and citrate synthase (CS) activity were measured on quadriceps muscle. Redox status was also quantified by measuring muscle antioxidant enzymatic activity and oxidative damage product, such as protein carbonyl content (PCC). Quercetin supplementation increased oxidative damage in both exercised and sedentary rats by inducing higher amounts ofPCC(P < 0.001). Quercetin supplementation caused higher catalase (P < 0.001) and superoxide dismutase (P < 0.05) activity in the non‐exercised animals, but not when quercetin is supplemented during exercise. Quercetin supplementation increasedSIRT1expression, but when quercetin is supplemented during exercise, this effect is abolished (P < 0.001). The combination of exercise and quercetin supplementation caused lower (P < 0.05)mtDNAcontent andCSactivity when compared with exercise alone. Quercetin supplementation during exercise provides a disadvantage to exercise‐induced muscle adaptations.