Gut commensal Lachnospiraceae bacteria contribute to anti-colitis effects of Lactiplantibacillus plantarum exopolysaccharides.

The probiotic Lactiplantibacillus plantarum (L. plantarum) could ameliorate colitis. Alterations in the composition of gut microbiota (GM) have been proved in cases of colitis. The exopolysaccharides from L. plantarum HMPM2111 (LPE) could be effective in colitis through altering the composition of the GM. These effects were linked to inhibiting intestinal inflammation, regulating the TXNIP/NLRP3 inflammasome axis, and attenuating colonic barrier dysfunction. The combination of fecal microbiota transplantation (FMT) and antibiotic inducement showed that gut bacteria susceptible to vancomycin were inversely associated with colitis features and were necessary for the anti-inflammatory effects of LPE. The elevated abundances of gut commensal Lachnospiraceae bacteria were associated with the restoration of colitis treated by LPE. Metabolomics analysis showed that colitis mice treated with LPE had higher levels of propionate and tryptophan metabolites generated from gut bacteria. The administration of these metabolites protected colitis and resulted in a reduction in inflammatory responses. The outcomes of our investigation emerge the significance of the GM in controlling the protective implications of LPE against colitis. Lachnospiraceae bacteria, together with downstream metabolites, contribute substantially to protection. This work elucidates the essential function of the GM-metabolite axis in producing comprehensive protection versus colitis and identifies prospective treatment targets.