A combined healthy strategy for successful weight loss, weight maintenance and improvement of hepatic lipid metabolism

Abstract

Obesity is critically related with the development of metabolic and pathophysiological alterations among which non-alcoholic fatty liver disease (NAFLD) is of especial relevance. Although there are numerous strategies to successfully treat obesity, the prevention of weight regain still remains challenging for individuals who have undergone weight loss programs. In such context, diet and physical activity are considered essential for the regulation of body weight and lipid metabolism. In this study, rats were fed a high-fat diet (HFD) to induce obesity and alterations in hepatic lipid metabolism. Obese rats were then treated with single or combined strategies of caloric restriction, physical exercise, and/or pharmacological treatment with an appetite suppressant, to lose weight, reverse the obesity-related alterations in hepatic morphology and lipid metabolism and maintain the beneficial effects of the interventions used. HFD induced excess body weight, hepatic steatosis, altered fatty acid profile, dysregulated gene expression of lipogenic and lipolytic enzymes, as well as plasma markers of liver damage, and modifications in liver antioxidant enzyme activity. Such alterations were ameliorated by caloric restriction in combination with a mixed training protocol and/or food-intake inhibitor administration during a weight loss intervention period of 3 weeks, and the beneficial effects remained after 6 weeks of weight maintenance, with some interesting interactions observed. In conclusion, weight loss strategies assayed were efficient at correcting the obesogenic action of a HFD and related alterations in hepatic functionality through different molecular mechanisms. The beneficial effects were also evident along the post-intervention maintenance period to avoid body weight regain.