Both Aerobic and Resistance Exercise Ameliorate Nonalcoholic Fatty Liver Disease Even in the Absence of Weight Reduction in High-fat Diet-induced Obese Mice

Abstract

Background: This study aimed at analyzing how aerobic and resistance exercise without dietary restriction could affect fat accumulation in the liver of high-fat diet (HFD)-induced obese mice.Methods: Mice, divided into normal (CO) and high-fat diet (HF) groups, were fed normal or 60 % HFD diets for 8 weeks, respectively. The HF group was then subdivided into HFD + sedentary (HF), HFD + aerobic training (HFAT), and HFD + resistance training (HFRT) groups. The mice in the training groups underwent treadmill or ladder climbing training for 8 weeks.Results: Although the HFAT and HFRT group body weight did not decrease, fat mass significantly decreased in the training groups than that in the HF group. Liver triglyceride levels in the HF group significantly increased compared to the CO group while no significant difference was detected in the training groups. HFD significantly induced an increase of liver cannabinoid-1 receptor, Sterol-regulatory element binding protein 1 (SREBP-1), and fatty acid synthase. Both aerobic and resistance training significantly induced the increase of liver carnitine palmitoyltransferase1, phosphor AMP-activated protein kinase (p-AMPK), and p-AMPK/AMPK while inducing a decrease of liver SREBP-1. However, the type of exercise did not cause any significant difference.Conclusions: Both aerobic and resistance exercise effectively improved fat mass and NAFLD even without weight reduction in HFD-induced obese mice. Therefore, a selected sustainable type of exercise based on the fitness level, type of disease, musculoskeletal disorders status, and preference of subjects, would be the best exercise intervention for alleviating NAFLD.