Dietary Cucumis melo reduces markers of muscle and articular inflammation following high-intensity exercise in horses

Abstract

We evaluated the antioxidative and anti-inflammatory potential of daily oral supplementation with a proprietary powdered Cucumis melo pulp (CMP) on exercise-induced markers of articular and muscular oxidative stress and inflammation in 12 horses. Horses performed a high-intensity exercise test immediately prior to, and then following, 3 weeks of daily supplementation of 1 g powdered CMP (CMP; n=8). Controls (Co; n=8) underwent the same exercise and sampling regime but were not supplemented. Blood and synovial fluid (SF) samples were taken 24 h prior to exercise (BL), and at 1 and 24 h following exercise. Plasma and SF were analysed for prostaglandin E2 (PGE2), total antioxidant status (TAS), nitrite and superoxide dismutase (SOD) activity. SF was analysed for glycosaminoglycans (GAG), and plasma was analysed for thiobarbituric acid reactive substances (TBARS). Comparisons were made using repeated measures with the initial exercise test as a covariate. There was an increase in SF SOD activity in the CMP group. Compared to Co at 1 h, CMP reduced nitrite and GAG in SF, as well as maintained plasma TAS and lymphocyte levels. At 24 h, plasma PGE2 and creatine kinase were lower in horses receiving CMP. Three weeks of supplementation with CMP reduced markers of articular and skeletal muscle oxidative stress and inflammation in response to high-intensity exercise in horses. Nutritive antioxidants may provide a useful adjunct to the daily nutrition plan of horses undergoing regular exercise training and competition.