Swimming training beneficial effects in a mice model of nonalcoholic fatty liver disease

The study aimed to investigate the effect of swimming training in reducing the nonalcoholic fatty liver disease (NAFLD) and associated comorbidities, including the hepatic expression of fatty acid synthesis and peroxisome proliferator receptor activity-alpha. Male C57BL/6 mice were separated into two major groups according to their nutrition and studied during 22 weeks: standard chow (10% fat, SC) or high-fat chow (60% fat, HF), characterizing the sedentary groups SC-Sed and HF-Sed. In the last 10 weeks of the experiment, half of the sedentary groups were submitted to a swimming training with a progressive increase in duration, characterizing the exercised groups: SC-Ex and HF-Ex. At the end of the experiment, considering the findings in the SC-Sed group, HF-Sed group had significantly higher body mass, hyperglycemia, hyperinsulinemia with insulin resistance, hypertrophy of the adipocytes (with inflammatory infiltrate), hypertrophy of the pancreatic islets, dyslipidemia, altered liver enzymes and inflammatory cytokines, and NAFLD with changes in gene expression of hepatic lipogenic and oxidative proteins. The swimming program, even concomitant with the high-fat diet, reduced overweight and all the other worst findings, especially NAFLD. In conclusion, the swimming training can attenuate the morbid effects of a high-fat diet combined with sedentary lifestyle in mice. These data reinforce the notion that swimming exercise can be considered an efficient nonpharmacologic therapy in the treatment of NAFLD, obesity and insulin resistance. (C) 2010 Elsevier GmbH. All rights reserved.