Anti-obesity effect of Lactobacillus rhamnosus LS-8 and Lactobacillus crustorum MN047 on high-fat and high-fructose diet mice base on inflammatory response alleviation and gut microbiota regulation

Purpose The objective of the study was to evaluate the anti-obesity effect of Lactobacillus rhamnosus LS-8 and Lactobacillus crustorum MN047, and illustrate the potential functional mechanism about the alleviation of high fat and high fructose diet (HFFD) induced obesity and related metabolic abnormalities. Methods C57BL/6J mice were subjected to a standard or HFFD with or without supplementation of L. rhamnosus LS-8 and L. crustorum MN047 for 10 weeks. Obesity related metabolic indices including glucose tolerance, insulin resistance, serum lipid, liver function, hormones and inflammatory cytokines were assessed by standard protocols. For the monitoring of inflammatory response and lipid metabolism, transcriptional levels were profiled in liver and/or adipose tissues. Furthermore, gut microbiota composition analyses in the fecal samples were performed using 16S rRNA gene sequencing, and gut microbial metabolites, including lipopolysaccharide (LPS) and short-chain fatty acids (SCFAs), were also tested for the assessment of the relationship between gut microbiota variation and inflammatory response. Results Administration with L. rhamnosus LS-8 and L. crustorum MN047 significantly mitigated body weight gain and insulin resistance, and inflammatory response (TNF-alpha, IL-1 beta and IL-6 levels in serum and corresponding mRNA levels in adipose tissues) was significantly inhibited in these two strains-treated mice. Moreover, L. rhamnosus LS-8 and L. crustorum MN047 could partially normalized mRNA expression levels involved in lipid metabolism including Ppar gamma, Srebp-1c, CD36, Fabp2 and FAS. In addition, these two strains manipulated gut microbiota by decreasing the abundance of Bacteroides and Desulfovibrio and increasing that of Lactobacillus and Bifidobacterium, which in turn raised the levels of feces SCFAs and lowered the levels of circulating LPS. Conclusion These results indicated that L. rhamnosus LS-8 and L. crustorum MN047 supplementation possessed the anti-obesity effect on the HFFD fed mice by alleviating inflammatory response and regulating gut microbiota, which further suggested that these two probiotics can be considered as an alternative dietary supplement in combination with the preventive and therapeutic strategies against obesity and related complications. Graphic abstract