Antifatigue effect of naringin on improving antioxidant capacity and mitochondrial function and preventing muscle damage.

The aim of this study was to explore effects of naringin (Nar) on antifatigue ability; the weight-loaded and non-loading swimming tests were performed. Compared with the control group, dietary supplementation of Nar significantly prolonged the weight-loaded swimming time to exhaustion of mice ( P  < 0.01). Nar significantly reduced the serum lactic acid (LD) level ( P  < 0.05) and lactate dehydrogenase (LDH) activity ( P  < 0.001), while increased the serum non-esterified free fatty acids (NEFA) level ( P  < 0.001). In addition, Nar significantly increased the liver glycogen and muscle glycogen contents ( P  < 0.05) and the phosphoenolpyruvate carboxykinase ( PEPCK ) ( P  < 0.01) and glucokinase ( GCK ) mRNA levels ( P  < 0.001) in liver and gastrocnemius (GAS) muscle. Furthermore, Nar significantly improved the antioxidant capacity, mitochondrial function, and muscle mitochondrial fatty acid β-oxidation ( P  < 0.05), and decreased inflammation and muscle damage-related gene expression ( P  < 0.05). These findings suggested that Nar can improve antifatigue effect by enhancing antioxidant capacity and mitochondrial function and preventing muscle damage.