Probiotics increase T regulatory cells and reduce severity of experimental colitis in mice

AIM:To investigate the effect of probiotics on regulating T regulatory cells and reducing the severity of experimental colitis in mice. METHODS:Forty C57/BL mice were randomly divided into four groups.Colitis was induced in the mice using 2,4,6-trinitrobenzene sulfonic acid (TNBS).After 10-d treatment with Bifico capsules (combined bifidobacterium, lactobacillus and enterococcus), body weight, colonic weight, colonic weight index, length of colon, and histological scores were evaluated.CD4 + CD25 + Foxp3 + T cell in mesenteric lymph nodes were measured by flow cytometry, and cytokines in colonic tissue homogenates were analyzed by a cytometric bead array. RESULTS:The colonic weight index and the colonic weight of colitis mice treated with Bifico were lower than that of TNBS-induced mice without treatment.However, colonic length and percent of body weight amplification were higher than in TNBS-induced mice without treatment.Compared with TNBS-induced mice without treatment, the level of CD4 + CD25 + Foxp3 + T cells in mesenteric lymph nodes, the expression of interleukin (IL)-2, IL-4 and IL-10 in colonic tissues from colitis mice treated with Bifico were upregulated, and tumor necrosis factor-α and interferon-γ were downregulated. CONCLUSION: Probiotics effectively treat experimental colitis by increasing CD4+ CD25 + Foxp3 + T cell and regulating the balance of Th1 and Th2 cytokines in the colonic mucosa.