BACKGROUND/OBJECTIVES: To investigate the effect and regulatory mechanism of resveratrol supplementation on the mitochondrial energy metabolism of rats with exerciseinduced fatigue.MATERIALS/METHODS: Forty-eight Sprague-Dawley male rats were divided randomly into a blank control group (C), resveratrol group (R), exercise group (E), and exercise and resveratrol group (ER), with 12 rats in each group. Group ER and group E performed 6-wk swimming training with 5% wt-bearing, 60 min each time, 6 days a wk. Group ER was given resveratrol 50 mg/kg by gavage one hour after exercise; group R was only given resveratrol 50 mg/kg by gavage; group C and group E were fed normally. The same volume of solvent was given by gavage every day. RESULTS: Resveratrol supplementation could reduce the plasma blood urea nitrogen content, creatine kinase activity, and malondialdehyde content in the skeletal muscle, increase the total superoxide dismutase activity in the skeletal muscle, and improve the fatigue state.Resveratrol supplementation could improve the activities of Ca2+ -Mg2+ -ATPase, Na+ -K+ -ATPase, succinate dehydrogenase, and citrate synthase in the skeletal muscle. Furthermore, resveratrol supplementation could up-regulate the sirtuin 1 (SIRT1)-proliferator-activated receptor gamma coactivator-1α (PGC-1α)-nuclear respiratory factor 1 pathway. CONCLUSIONS Resveratrol supplementation could promote mitochondrial biosynthesis via the SIRT1/PGC-1α pathway, increase the activity of the mitochondrial energy metabolismrelated enzymes, improve the antioxidant capacity of the body, and promote recovery from exercise-induced fatigue.

BACKGROUND:Resveratrol is a natural antioxidant extracted from plants.Its mechanism of improving exercise-induced fatigue mainly focuses on the protective effect against oxidative stress and inflammation.In this study,the protective mechanism of resveratrol on exercise-induced fatigue was mainly discussed from the perspective of gluconeogenesis. OBJECTIVE:To investigate the effect of resveratrol on gluconeogenesis in exercise-induced fatigue rats. METHODS:After 1 week of adaptive training,male Sprague-Dawley rats were randomly divided into 4 groups with 12 rats in each group:blank control group,resveratrol group,exercise group,resveratrol + exercise group.Weight-bearing swimming training was used to simulate long-term medium-high intensity exercise.After swimming with a weight of 5%for 1 hour every day,50 mg/kg resveratrol solution or the same volume of dimethyl sulfoxide solvent were given orally,6 days a week,for a total of 6 weeks.Samples were collected 24 hours after the last exercise,and the levels of urea nitrogen,creatine kinase,blood glucose,liver glycogen and lactic acid and pyruvate in liver tissue were detected by the kit.The activity of phosphoenolpyruvate carboxykinase was detected by microassay,and the activity of glucose-6-phosphatase was detected by enzyme-linked immunosorbent assay.Real-time fluorescence quantitative PCR was used to detect the gene expression of silent information regulator 1,cAMP-response element binding protein and peroxisome proliferator-activated receptor-γ coactivator-1α. RESULTS AND CONCLUSION:In the exercise group,plasma urea nitrogen and creatine kinase levels of rats were significantly increased(both P<0.05),liver lactate and pyruvate levels and lactate/pyruvate ratio were significantly increased(all P<0.01),and blood glucose and liver glycogen contents were significantly decreased(both P<0.01).Resveratrol supplementation could effectively improve the above conditions.Exercise significantly decreased the activities of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase(P<0.01,P<0.05),and resveratrol supplementation significantly increased the activity of phosphoenolpyruvate carboxykinase in liver tissue(P<0.01).The mRNA expression levels of silent information regulator 1,cAMP-response element binding protein and peroxisome proliferator-activated receptor-γ coactivator-1α in liver tissue of the exercise group were significantly decreased(all P<0.01),while resveratrol supplementation could significantly increase the gene expression levels of this pathway.To conclude,resveratrol can relieve exercise-induced fatigue caused by long-term medium-high intensity exercise,and its mechanism may be related to up-regulating the gluconeogenesis regulatory pathway,improving rate-limiting enzyme activity,promoting liver gluconeogenesis,and increasing blood glucose and liver glycogen levels.

Macroautophagy (referred to as autophagy hereafter) is a major intracellular lysosomal degradation pathway that is responsible for the degradation of misfolded/damaged proteins and organelles. Previous studies showed that autophagy protects against acetaminophen (APAP)-induced injury (AILI) via selective removal of damaged mitochondria and APAP protein adducts. The lysosome is a critical organelle sitting at the end stage of autophagy for autophagic degradation via fusion with autophagosomes. In the present study, we showed that transcription factor EB (TFEB), a master transcription factor for lysosomal biogenesis, was impaired by APAP resulting in decreased lysosomal biogenesis in mouse livers. Genetic loss-of and gain-of function of hepatic TFEB exacerbated or protected against AILI, respectively. Mechanistically, overexpression of TFEB increased clearance of APAP protein adducts and mitochondria biogenesis as well as SQSTM1/p62-dependent non-canonical nuclear factor erythroid 2-related factor 2 (NRF2) activation to protect against AILI. We also performed an unbiased cell-based imaging high-throughput chemical screening on TFEB and identified a group of TFEB agonists. Among these agonists, salinomycin, an anticoccidial and antibacterial agent, activated TFEB and protected against AILI in mice. In conclusion, genetic and pharmacological activating TFEB may be a promising approach for protecting against AILI.