Role of a probiotic strain in the modulation of gut microbiota and cytokines in inflammatory bowel disease.

Objective: To assess the effect of a probiotic strain Bacillus clausii UBBC-07 on gut microbiota and cytokines in IBD patients.

Method: Patients were randomly allocated to either placebo or probiotic Bacillus clausii UBBC-07 for four weeks along with the standard medical treatment (SMT). Enrolled patients were evaluated before and after intervention for presence of the given probiotic, change in gut microbiota, change in serum cytokines, serotonin and dopamine, symptoms of disease, physical, behavioral and psychological parameters.

Results: Probiotic strain Bacillus clausii UBBC-07 showed good survival in IBD patients in the treatment group (p < 0.01) without any reported adverse event. Metagenomic analysis showed that the given probiotic strain was able to modulate the gut microbiota in treated group. Phylum Firmicutes was increased and phylum Bacteroidetes was decreased in the probiotic treated group. A significant increase was observed in the abundance of anaerobic bacterial genera Lactobacillus, Bifidobacterium and Faecalibacterium in the probiotic treated group (p < 0.01) as compared to placebo group. Significant increase was observed in IL-10 (p < 0.05) and variable decrease in the secretion of IL-1β, TNF- α, IL-6, IL -17 and IL -23 in probiotic treated group. In the treatment group a significant decrease in the symptoms of IBD and improvement in the psychological parameter to various degrees was noted.

Conclusion: These results indicated that probiotic strain B clausii UBBC-07 affected the gut microbiota and cytokine secretion and shown efficacy in IBD patients.