Abstract:

BACKGROUND: Resveratrol is a polyphenolic compound found in grapes, peanuts, quinoa and other plants, and act as a kind of health food supplement. Resveratrol supplementation can alleviate exercise fatigue but its specific mechanism is still unclear. This study attempted to investigate its mechanism from the perspective of mitochondrial dynamics.
OBJECTIVE: To investigate the effect of resveratrol supplementation on mitochondrial dynamics in a rat model of exercise-induced fatigue.
METHODS: Forty-eight Sprague-Dawley male rats were randomly divided into blank control group, resveratrol group, exercise group and exercise+resveratrol group (n=12 per group). The exercise+resveratrol group and the exercise group simultaneously performed a 6-week swimming training with a weight of 5%, 60 minutes once, 6 days per week. The exercise+resveratrol group was given resveratrol 50 mg/kg by gavage 1 hour after exercise and the resveratrol group was only given resveratrol 50 mg/kg by gavage. The blank control and exercise groups were fed with the same volume of solvent every day. Samples were collected at 24 hours after the last exercise. Blood urea nitrogen level, malondialdehyde content, and superoxide dismutase activity in plasma were measured. mRNA expression levels of mitochondrial fusion-related factors (mitochondrial fusion protein 1, mitochondrial fusion protein 2, optical atrophy 1) and fission-related factors (dynamin-related protein 1 and mitochondrial fission protein 1) in the skeletal muscle were determined. 
RESULTS AND CONCLUSION: Compared with the blank control group, the levels of blood urea nitrogen and malondialdehyde in the plasma were significantly increased in the exercise group (both P < 0.05), and the superoxide dismutase activity was significantly decreased (P < 0.05). Compared with the exercise group, the levels of urea nitrogen and malondialdehyde in the plasma were significantly decreased in the exercise+resveratrol group (P < 0.01, P < 0.05), and the activity of superoxide dismutase was significantly increased (P < 0.01). Compared with the blank control group, the mRNA expressions of mitochondrial fusion proteins 1 and 2 were significantly decreased in the exercise group (P < 0.01, P < 0.05). Compared with the exercise group, the mRNA expressions of mitochondrial fusion proteins 1 and 2 and optical atrophy 1 were significantly increased in the exercise+resveratrol group (P < 0.01, P < 0.05, P < 0.05). Compared with the blank control group, the mRNA expressions of dynamin-related protein 1 and mitochondrial fission protein 1 were significantly increased in the exercise group (P < 0.01, P < 0.01). Compared with the exercise group, the mRNA expressions of dynamin-related protein 1 and mitochondrial fission protein 1 were significantly decreased in the exercise+resveratrol group (P < 0.01, P < 0.05). These findings indicate that supplementation of resveratrol can promote mitochondrial fusion, inhibit excessive mitochondrial fission, improve mitochondrial dynamics disorder, and accelerate the elimination of exercise-induced fatigue in the rat model of fatigue.

Key words: exercise-induced fatigue, resveratrol, mitochondrial dynamics, mitochondrial fusion, rat