Aerobic exercise and vitamin E improve high-fat diet-induced NAFLD in rats by regulating the AMPK pathway and oxidative stress

Abstract

Background and aims: Non-alcoholic fatty liver disease (NAFLD) has emerged as a major chronic liver disease. We explored simple and effective ways to improve NAFLD and investigate the mechanism of action.

Methods: NAFLD was induced in 40 rats fed a high-fat diet (HFD). Magnetic resonance imaging was used to evaluate the progression and improvement of NAFLD. The treatment-related interventions included aerobic exercise (E) and vitamin E (VE) supplementation. Expression levels of proteins related to fat metabolism were also assessed. The activities of antioxidant enzymes in the liver and serum lipid metabolism were analyzed using biochemical methods.

Results: Aerobic exercise and vitamin E effectively improved NAFLD in rats, resulting in decreased hepatic fat accumulation, reduced hepatocyte ballooning, and decreased triglyceride levels. Combination therapy achieved the best effect. Both aerobic exercise and vitamin E activate the AMPK pathway to phosphorylate acetyl-CoA carboxylase (ACC) and reduce fatty acid synthesis. The expression of sterol regulatory element-binding protein-1 (SREBP-1) was decreased significantly in the treated groups, particularly in the E + VE + HFD group. The expression of carnitine palmitoyl-transferase 1C (CPT1C) significantly increased in the treated groups, particularly in the E + VE + HFD group. Compared with the control group, reactive oxygen species (ROS) in the E + HFD group were slightly decreased, while that in the VE + HFD group were significantly decreased, with the even greater reduction observed in the E + VE + HFD group.

Conclusion: Aerobic exercise and vitamin E supplementation can improve HFD-induced NAFLD in rats by regulating the AMPK pathway and reducing oxidative stress.

Keywords: Aerobic exercise; Antioxidants; Fat metabolism; NAFLD.