Exercise and Low Fat Diet Improve Peritoneal Macrophage Immunocompetence In Obese Mice

Abstract

PURPOSE: This study investigated the effect of moderate exercise training on macrophage immunocompetence in high fat diet-induced obese mice. METHODS: To determine the effects of exercise training and high/low fat diet on macrophage, C57BL/6 male mice(4 weeks aged, n=32) were fed high fat diet(40% fat diet) for 5 weeks so that obesity was led intentionally. Then these obese mice were divided into 4 groups; LC (low fat diet(10% fat) and no exercise; n=8), LE (low fat diet and exercise; n=8), HC (high fat diet and no exercise; n=8) or HE (high fat diet and exercise; n=8). HC and LC mice performed 8wks of exercise training on a motorized treadmill running for 30-60 min/day at 10-22 m/min, 0% grade, five times per week for 8wks. Peritoneal macrophage was isolated and analyzed. RESULTS: Macrophage phagocytosis of LE was significantly different to that of LC. Nitric oxide production of LE stimulated by LPS and/or IFN-g significantly higher than that of LC. TNF-a production of LE stimulated by LPS was significantly higher than that of LC. IL-1 b production of LE was significantly higher than that of LC. However, IL-1 b production of HE was significantly lower than that of HC. IFN-g production of LE was significantly higher than that of LC. However, IFN-g production of HE was significantly lower than that of HC. IL-12 production of HE was significantly lower than that of HC, but there was no different between LE and LC. CONCLUSION: These findings suggest that the effect of moderate exercise depends on type of diet(low and high fat diet). However, long-term moderate exercise has more beneficial effects on macrophage immunocompetence by improving Macrophage phagocytosis, TNF- a, IL-1 b and IFN-g production in low-fat diet groups. Key words; fat diet, immunocompetence, macrophage, exercise training