Comparison of the Enteric Mucosal Immunomodulatory Activity of Combinations of Coptis chinensis Franch. Rhizomes and Evodia rutaecarpa (Juss.) Benth. Fruits in Mice with Dextran Sulphate Sodium-Induced Ulcerative Colitis

Combinations of crude rhizomes of Coptis chinensis Franch., Ranunculaceae, and fruits of Evodia rutaecarpa (Juss.) Benth., Rutaceae, at a ratio of 6: 1 (formula A) and 1: 6 (formula B) were extracted with boiling water, and their modulatory activity on enteric mucosal immune responses in mice with dextran sulphate sodium-induced ulcerative colitis was investigated. The results showed that both formulas could reduce the severity of inflammation in the colon. Formula A at a low dose can decrease myeloperoxidase (MPO) activity, and formula B was inactive. Both formulas did not affect the percentages of CD4(+) and CD8(+) T cells in the periphery, but they evoked an increase of CD8(+) T cells among the enteric intra-epithelial lymphocytes. Formula B at a low dose could increase both CD4(+) and CD8(+) cells, and formula A at a high dose could only increase CD8(+) T cells among the Peyer's patch lymphocytes (p < 0.05). Both formulas did not affect the percentages of CD4(+) and CD8(+) T cells among the lamina propria lymphocytes, but decreased the serum concentration of IL-1 beta (p < 0.05 at a low dose of formula A) and enhanced the level of IL-10 in serum (p < 0.05 at a low dose formula B). We conclude that both formulas have a similar modulating effect on enteric mucosal immune responses, the major difference being that formula A could decrease the level of IL-1 beta, while formula B could increase the IL-10 dose in serum.