Bifidobacterium Breve SHMB 8001 Alleviates DSS‐Induced Colitis in Mice Via Modulating the Intestinal Barrier and Gut Microbiota

Microbial-based therapies, including probiotics, may provide complementary approaches for treating inflammatory bowel disease (IBD). Our research evaluated the efficacy of a novel human breast milk-derived probiotic strain, Bifidobacterium breve (B. breve) SHMB 8001, against colitis in mice following dextran sulfate sodium (DSS) challenge and elucidated its molecular basis. B. breve SHMB 8001 administration alleviated DSS-induced alterations in body mass, disease activity index (DAI), colon dimensions (p = 0.007), and tissue histology (p < 0.001). SHMB 8001 increased the colonic levels of critical barrier proteins MUC2 (p < 0.001), occludin (p < 0.001), and claudin-1 (p < 0.001), as measured by qPCR and western blotting. SHMB 8001 significantly elevated the levels of fecal short-chain fatty acids (SCFAs) and colonic G protein-coupled receptor (GPR) 43 (p = 0.023) and the percentage of CD4⁺ CD25⁺ FOXP3⁺ Treg cells (p = 0.009), as determined by gas chromatography-mass spectrometry (GC-MS), qPCR, and flow cytometry, respectively. Furthermore, qPCR revealed that SHMB 8001 up regulated the colonic expression of interleukin (IL)-10 (p = 0.010) but suppressed the expression of IL-1β (p = 0.013), IL-6 (p = 0.005), and tumor necrosis factor (TNF)-α (p = 0.021). High-throughput 16S rRNA gene sequencing revealed that SHMB 8001 modulated the composition of the gut micro biota by enriching bacterial genera capable of producing SCFAs, including Bifidobacterium, norank_f_Muribaculaceae, and Lactobacillus, and partially restored the microbial functional pathways altered by DSS. In conclusion, this study demonstrates that B. breve SHMB 8001 represents a potential probiotic strain for alleviating colitis by normalizing intestinal homeostasis. PRACTICAL APPLICATIONS: This research evaluated the efficacy of a novel human breast milk-derived probiotic strain, B. breve SHMB 8001, against colitis in mice following dextran sulfate sodium (DSS) challenge, and delineated its molecular basis. B. breve SHMB 8001 represents a potential probiotic strain for alleviating colitis via normalizing intestinal homeostasis.