Anti-Obesity Effects and Changes of Fecal Microbiome by Lactic Acid Bacteria from Grains in a High-Fat Diet Mouse Model

Background/Objectives: Probiotics may be a promising strategy for treating metabolic disorders and obesity. This study aims to explore useful lactic acid bacteria with anti-obesity effects from grains. Methods: Three lactic acid bacterial strains with anti-adipogenic effects in C3H10T1/2 cells and possessing useful probiotic properties were administrated to mice on a high-fat diet. Lactiplantibacillus plantarum RP12 exhibiting a more pronounced anti-obesity effect was utilized for further studies. Results: Oral administration of Lactiplantibacillus plantarum RP12 resulted in reduced body weight gain and epididymal fat mass. Significant reductions in serum total cholesterol, triglycerides and blood glucose were observed in the group treated with Lactiplantibacillus plantarum RP12. This strain was found to regulate the expression of genes related to lipid metabolism in epididymal adipose tissue and liver, and induced changes in the composition of fecal microbiota. Notable differences in the compositions at the family, genus and species levels were evident between the HFD and RP12 groups. Specially, differences in proportions of some taxa reported to have association with obesity were observed between the two groups. Fecal analyses demonstrated that Lactiplantibacillus plantarum RP12 diminishes lipid absorption and augment the production of short-chain fatty acids in the intestine. Lactiplantibacillus plantarum RP12 mitigated damage to the morphology of the ileum and colon caused by a high-fat diet and promoted the expression of Claudin-1 and Muc2. Conclusions: Lactiplantibacillus plantarum RP12 has potential as a therapeutic probiotic to address metabolic disorders as well as obesity, substantiating the positive in vivo indicators and modulation of gut microbiota in a high-fat diet-induced obese mouse model.