Modulation of gut microbiota and anti-inflammatory effect of a probiotic cocktail in an inflammatory bowel disease-induced mouse model by fecal transplantation

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract due to altered interaction between the immune system and the gut microbiota. The aim of this study was to investigate the role of a probiotic cocktail in modulating immune dysregulation induced in mice. Mice were divided into five groups (n = 5/group) and inflammation was induced by fecal microbiota transplantation (FMT) from the stool of human with IBD and dextran sulfate sodium (DSS). The cocktail of Lactobacillus spp. and Bifidobacterium spp. (10⁸CFU/kg/day) was administered daily for a total of 28 days. The alteration of the gut microbiota and the expression of some genes involved in the regulation of the inflammatory response were studied in the probiotic-treated and untreated groups by quantitative real-time PCR. The gut microbiota of the FMT and DSS groups showed similar patterns on day 28 after each treatment. In the probiotic-treated groups, the population of the gut microbiota normalized and, in contrast to the DSS and FMT groups, the abundance of phyla Firmicutes and Actinobacteria increased. The expression of genes related to immune response and tight junctions was positively affected by the probiotic. Changes in the gut microbiota could influence the inflammatory status in the gut, and probiotics as a preventive or complementary treatment could improve the well-being of patients with inflammatory bowel disease symptoms.