Lactobacillus plantarum AR113 alleviates DSS-induced colitis by regulating the TLR4/MyD88/NF-κB pathway and gut microbiota composition

Probiotics are a potential treatment agent for IBD. In this study, the effects of probiotics on intestinal immune responses and gut microbiota in colitis were investigated. The result showed that L. plantarum AR113 and L. casei AR342 were 2–3 times more effective than other strains to alleviate epithelial damage indicators, improve colon length (+10–30%) and maintain the integrity of the epithelial barrier, as compared to DSS-treatment mice. The supplementation downregulated expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and upregulated that of the colonic anti-inflammatory cytokine (IL-10). The results strongly suggested that anti-inflammatory effect of probiotics is associated with the increase in HO-1 expression and the decrease in TLR4/MyD88/NF-κB pathway expression in mouse colonic tissues. Further, Microbiota analysis and the correlation of microbiota with colitis parameters revealed that the dysbiosis of gut microbiota induced by DSS treatment could be mitigated to a certain extent by supplementation with L. plantarum AR113.