Lactobacillus plantarum 17-1 Ameliorates DSS-Induced Colitis by Modulating the Colonic Microbiota Composition and Metabolome in Mice.

Background/Objectives: Lactobacillus strains are widely used as probiotics in the functional food industry and show potential for treating inflammatory bowel disease (IBD). However, the strain specificity and limited stress resistance of Lactobacillus restricts its therapeutic effectiveness. The aim of this study was to investigate the effects of dietary supplementation with microencapsulated Lactobacillus plantarum 17-1 on the intestinal immune responses, gut microbiota composition, and metabolic characteristics in colitis mice. Methods: Mice were pre-fed a diet containing microencapsulated Lactobacillus plantarum 17-1 for 3 weeks and then treated with 2.5% dextran sulfate sodium (DSS) in drinking water for 8 days to induce colitis. Results: The results showed that microencapsulated Lactobacillus plantarum 17-1 effectively alleviated clinical symptoms and histopathological features of colitis mice and suppressed the up-regulation of pro-inflammatory cytokines IL-6 and IL-17 in the colon of colitis mice. Additionally, Lactobacillus plantarum 17-1 significantly increased the relative abundance of several beneficial bacterial taxa, including Ruminococcaceae_UCG_014, Bacteroides, Prevotellaceae_UCG_001, Lactococcus, Weissella, Pediococcus, and so on. Moreover, it regulated the levels of multiple inflammation-related metabolites involved in linolenic acid metabolism, arachidonic acid metabolism, primary bile acid biosynthesis, and tyrosine metabolism. Conclusions: These results suggest that dietary supplementation with microencapsulated Lactobacillus plantarum 17-1 reduced colitis inflammation in mice by modulating the intestinal microbiota composition and metabolic characteristics, which may serve as a potential therapeutic strategy for IBD.