The effects of Korean mistletoe extract on endurance during exercise in mice

Many investigators have screened drugs and foods for the enhancement of endurance capacity and antifatigue. Mistletoe, a semiparasitic plant on various deciduous trees, has many known biological activities, including anticancer, anti-diabetes, antioxidant, and anti-cardiovascular disease effects. In a previous study, Korean mistletoe extract (KME) was reported to increase endurance capacity in mice. However, whether the administration of KME further enhances exercise performance, when combined with exercise training, was not investigated. In this study, we demonstrate that the administration of KME decreases the level of plasma lactate dehydrogenase, parameter of tissue damage and muscle fatigue when combined with exercise training. Exercise training increases the muscular glycogen and plasma free fatty acid (FFA) level, and KME administration in sedentary mouse group increases the plasma FFA level, indicating that KME administration alters the energy resources in muscle. In addition, KME administration enhances the exercise performance in sedentary mouse group, but did not further enhance exercise performance when combined with exercise training, suggesting that KME could be an excellent mimetic of exercise.