leaves suppress sodium dextran sulfate-induced colitis through interleukin-10-related pathway.

Indigo naturalis, a herbal medicine purified from indigo-containing plants, such as and , has been reported to be useful in the treatment of ulcerative colitis by activating the aryl hydrocarbon receptor. However, the aryl hydrocarbon receptor pathway causes crucial side effects, such as pulmonary arterial hypertension. Although is one of the plant derivatives of indigo naturalis, it is not identical to it To date, the pure leaves of have not been reported to ameliorate ulcerative colitis. Therefore, we investigated the effect of pure leaves, which are consumed in some regions, on experimental colitis induced in mice using sodium dextran sulfate. We found that leaves ameliorated weight loss (P < 0.01) and pathological inflammatory changes in the colon (P < 0.05), enhanced mRNA expression of interleukin-10 (P < 0.05), and decreased expression of tumor necrosis factor-in colonic tissues (P < 0.05), as determined using quantitative real-time reverse transcription polymerase chain reaction. The intraperitoneal administration of an aryl hydrocarbon receptor antagonist did not antagonize the inhibition of mucosal destruction, whereas an anti-interleukin-10 receptor antibody did. These results suggest that ameliorate sodium dextran sulfate-induced intestinal inflammation via interleukin-10-related pathway, independent of the aryl hydrocarbon receptor pathway. leaves have the potential to be a new, safe treatment for ulcerative colitis.