Lactobacillus fermentumpromotes adipose tissue oxidative phosphorylation to protect against diet-induced obesity

The gut microbiota has pivotal roles in metabolic homeostasis and modulation of the intestinal environment. Notably, the administration ofLactobacillusspp. ameliorates diet-induced obesity in humans and mice. However, the mechanisms through whichLactobacillusspp. control host metabolic homeostasis remain unclear. Accordingly, in this study, we evaluated the physiological roles ofLactobacillus fermentumin controlling metabolic homeostasis in diet-induced obesity. Our results demonstrated thatL. fermentum-potentiated oxidative phosphorylation in adipose tissue, resulting in increased energy expenditure to protect against diet-induced obesity. Indeed, oral administration ofL. fermentumLM1016 markedly ameliorated glucose clearance and fatty liver in high-fat diet-fed mice. Moreover, administration ofL. fermentumLM1016 markedly decreased inflammation and increased oxidative phosphorylation in gonadal white adipose tissue, as demonstrated by transcriptome analysis. Finally, metabolome analysis showed that metabolites derived fromL. fermentumLM1016-attenuated adipocyte differentiation and inflammation in 3T3-L1 preadipocytes. These pronounced metabolic improvements suggested that the application ofL. fermentumLM1016 could have clinical applications for the treatment of metabolic syndromes, such as diet-induced obesity. Obesity: Microbial defenders of metabolic health The presence of particular bacterial species in the healthy gut microbiome can reduce the risk of obesity by modulating metabolic activity in host tissues. Several studies have suggested that intestinal microbes from the genusLactobacilluscan counteract weight gain and fat accumulation in humans and mice. Researchers in South Korea led by Sungsoon Fang at Yonsei University College of Medicine, Seoul, and Hansoo Park at the Gwangju Institute of Science and Technology have now examined the physiological effects of one such species,Lactobacillus fermentumLM1016, in mice. The researchers showed that this bacterium could reduce the risk of diet-induced obesity and fat accumulation in the liver, and identified relevant shifts in the activity of key metabolic and inflammatory pathways. If these findings are confirmed in humans, this bacterial strain could serve as an effective probiotic.