Effects of different Lactobacillus reuteri on inflammatory and fat storage in high-fat diet-induced obesity mice model

•L. reuteri L3 and L. reuteri L10 were isolated from normal mice and obese mice, respectively.•L. reuteri L3 prevented diet-induced obesity, but not L. reuteri L10.•L. reuteri L3 (but not L. reuteri L10) decreased lipopolysaccharide, pro-inflammatory cytokine levels.•Bacterial strains of the same species showed different effects on inflammatory and obesity. Lactobacillus reuteri L3 and Lactobacillus reuteri L10 were selected to investigate whether different strains from the same probiotic species, but isolated from different phenotype mice (normal or obese mice), modulated metabolic phenotypes such as obesity. The results indicate that L. reuteri L3 (but not L. reuteri L10) significantly decreased body weight, glucose, insulin, lipopolysaccharide (LPS), and pro-inflammatory cytokine levels and increased energy expenditure (measured by heat production and ambulatory activity) compared with the high-fat diet group. Moreover, the mRNA levels of Ppar-γ, Acc1, and Fas in adipocytes were significantly suppressed, and the mRNA level of Cyp7a1 in liver was promoted by L. reuteri L3, not by L. reuteri L10. These activities may contribute to significant anti-obesity effects of L. reuteri L3. In addition, bacterial strains of the same species showed different effects on inflammatory and obesity, illustrating the complexity of host-bacterial cross-talk and the importance of investigating specific bacterial strains.