A Novel Synbiotic Protects Against DSS-Induced Colitis in Mice via Anti-inflammatory and Microbiota-Balancing Properties

Inflammatory bowel disease (IBD) is a chronic immune-inflammatory disease. Gut microbes, intestinal immunity, and gut barrier function play a critical role in IBD. Growing evidence suggests that synbiotic may offer therapeutic benefits for individuals with colitis, suggesting an alternative therapy against colitis. With this in mind, we creatively prepared a new synbiotic combination consisting of a probiotic strain (Limosilactobacillus reuteri) along with one prebiotic chitooligosaccharides (COS). The protective effects of the synbiotic on DSS-induced colitis and the underlying mechanisms were investigated. We demonstrated that the synbiotic ameliorated colitis in mice, as evidenced by a significant remission in body weight loss and colon shortening, and a decreased disease activity index (DAI). Notably, synbiotic reduced the intestinal inflammation and injury by synergistically decreasing inflammatory factors, inhibiting TLR4/Myd88/NF-κB/NLRP3 signaling, preventing macrophage infiltration, and enhancing the integrity of the intestinal barrier. Moreover, synbiotic selectively promoted the growth of beneficial bacteria (e.g., Akkermansia, Lactobacillus) but decreased the pathogenic bacteria (e.g., Helicobacter). BugBase's analysis supported its ameliorated role in reducing pathogenic bacteria. Collectively, our findings revealed the novel synbiotic had a potential to treat colitis, which was associated with its anti-inflammatory and microbiota-balancing properties. This study will contribute to the development of functional synbiotic products for IBD therapy and will provide valuable insights into their mechanisms.