Effect of Jiaweiwumei decoction on regulatory T cells and interleukin-10 in a rat model of ulcerative colitis

OBJECTIVE: To investigate the effect of a decoction made from the Traditional Chinese Medicine wumei pill, on regulatory T cells and interleukin-10 (IL-10) in a rat model of ulcerative colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). METHODS: Rat ulcerative colitis was induced with TNBS. All modeled rats were randomly divided into six groups: normal control group; model group; sulfasalazine suppositories treatment group; and high, moderate, and low dosage of jiaweiwumei decoction groups (12 rats each). Colon injury index was evaluated after 14 days. After peripheral blood lymphocyte separation, CD4+ T cells and CD4+/CD25+ T cell percentage was detected by flow cytometry. The content of IL-10 in serum and intestinal mucosa tissue was detected by sandwich enzyme-linked immunosorbent assay. RESULTS: Colon injury indices in the decoction groups were effectively reduced, compared with the model group (P < 0.05). Compared with that of the control group, the CD4+/CD25+ to CD4+ T lymphocyte ratio of the model group was significantly lower, while the decoction treatment improved the CD4 +/CD25 + to CD4 + T lymphocyte ratio (P < 0.05). The serum and mucosal IL-10 content of the model group was significantly lower (P < 0.05) than that in the control group, while the decoction group had significantly higher serum and intestinal mucosal IL-10 content than that in the model group (P < 0.05). The regulatory T cell content was negatively correlated with the colonic injury index (r = 0.68, P < 0.05), and positively correlated with the content of serum IL-10 (r= 0.87, P < 0.05) and intestinal mucosal IL-10 (r= 0.79, P < 0.05). CONCLUSION: Jiaweiwumei decoction had significant effects on regulatory T cells and IL-10 in rats with TNBS-induced ulcerative colitis.