Lipoic acid prevents body weight gain induced by a high fat diet in rats: effects on intestinal sugar transport

Several studies have suggested that oxidative stress might cause and aggravate the inflammatory state associated with obesity and could be the link between excessive weight gain and its related disorders such as insulin resistance and cardiovascular diseases. Thus, antioxidant treatment has been proposed as a therapy to prevent and manage obesity and associated complications. Therefore, the aim of the present study was to investigate the effects of supplementation of a standard or high fat diet with the antioxidant lipoic acid (LA) during 56 days, on body weight gain, adiposity, feed efficiency and intestinal sugar absorption, in male Wistar rats. LA supplementation induced a lower body weight gain and adipose tissue size in both control or high fat fed rats accompanied by a reduction in food intake. The group fed on a high fat diet and treated with LA (OLIP group) showed a lower body weight gain than its corresponding Pair-Fed (PF) group (P < 0.05), which received the same amount of food than LA-treated animals but with no LA. In fact, LA induced a reduction on feed efficiency and also significantly decreased intestinal alpha-methylglucoside (alpha-MG) absorption both in lean and obese rats. These results suggest that the beneficial effects of dietary supplementation with LA on body weight gain are mediated, at least in part, by the reduction observed in food intake and feed efficiency. Furthemore, the inhibitory action of LA on intestinal sugar transport could explain in part the lower feed efficiency observed in LA-treated animals and therefore, highlighting the beneficial effects of LA on obesity.