Bifidobacterium breve CCFM683 could ameliorate DSS-induced colitis in mice primarily via conjugated linoleic acid production and gut microbiota modulation

Probiotics have been proposed as the alternative therapy for IBD, but with strong strain-dependent effects. The current work aims to investigate the protective effect of B. breve CCFM683 on a DSS-induced colitis. CCFM683 significantly inhibited disease activity index, colon shortening and myeloperoxidase activity. Additionally, CCFM683 improved the histological damage, protected the colonic mucous layer integrity and significantly attenuated the expression of pro-inflammatory cytokines (TNF-alpha, IL-1 beta, IL-6), while up-regulated the expression of colonic anti-inflammatory cytokine IL-10 and nuclear receptor PPAR gamma. Meanwhile, the concentration of colonic conjugated linoleic acid (CLA) was significantly increased in response to CCFM683 supplementation, which demonstrates that CCFM683 prevents colitis in correlation with local CLA production. Furthermore, CCFM683 could rebalance the gut microbial composition damaged by DSS, including reducing the abundance of Romboutsia, Porphyromonadaceae, Desulfovibrionaceae as well as increasing the abundance of Peptostreptococcaceae, which indicated that gut microbiota reconstruction might be another factor for CCFM683 protection against colitis.