Effect of hydroalcoholic extract ofAegle marmelosfruit on radical scavenging activity and exercise-endurance capacity in mice

Aegle marmelos L. Corr (Rutaceae) is an important Indian Ayurvedic medicinal plant used for the treatment of various ailments. However, little information is available on the anti-fatigue properties of its fruit.Evaluation of the physical endurance and exercise-induced oxidative stress modulating properties of A. marmelos fruit in mice.Radical scavenging activity of the fruit hydroalcoholic extract was evaluated using in vitro systems. The extract was further evaluated for its endurance-enhancing properties at three oral doses (100, 200 and 400 mg/kg b.wt) in BALB/c mice for 21 d using a swimming test.The extract exhibited significant scavenging activity against DPPH (IC₅₀, 351 ± 37 µg/ml) and ABTS radicals (IC₅₀, 228 ± 25 µg/ml), respectively, with the polyphenol content of 95 µg/mg extract. It also inhibited AAPH radical-induced oxidation of biomolecules such as BSA protein (63%), plasmid DNA (81%) and lipids (80.5%). Administration of extract resulted in an increase in the duration of swimming time to exhaustion by 23.4 and 47.5% for medium and higher doses, respectively. The extract significantly normalized the fatigue-related biochemical parameters and also down-regulated the swim stress-induced over-expression of heat shock protein-70 and up-regulated the skeletal muscle metabolic regulators (GLUT-4 and AMPK1-α) by 2- and 3-fold, respectively, at the higher dose in muscle tissues.Our study demonstrates the anti-fatigue properties of A. marmelos fruit, most probably manifested by delaying the accumulation of serum lactic acid, increasing the fat utilization and up-regulating the skeletal muscle metabolic regulators.