Objective: To investigate the effect of Changyanqing decoction, a traditional Chinese medicinal preparation, on the expressions of interleukin-10 (IL-10) and intercellular adhesion molecule-1 (ICAM-1) in the colon mucosa of rats with ulcerative colitis.
Methods: The rats with ulcerative colitis induced by trinitrobenzene sulphonic acid and ethanol enema were randomly divided into 3 groups, namely the model group, sulfasalazine (SASP) group, and Changyanqing decoction group. Daily treatment with intragastric administration and enema of normal saline, SASP (100 mg/kg), and Changyanqing decoction (39.75 mg/kg), respectively, were administered 24 h after the establishment of colitis till the end of the experiment. Another group of rats was used as the normal control group. The disease activity index (DAI) and colon mucosa damage index (CMDI) of the rats were calculated. The activity of myeloperoxidase (MPO) was measured by biochemical method, and the expressions of IL-10 and ICAM-1 protein were measured by ELISA and immunohistochemistry, respectively.
Results: Compared with the normal group, the model group showed significantly increased DAI, CMDI, HS score and MPO activity in the colon tissues (P < 0.01), with also significantly increased expression of ICAM-1 (P < 0.01) and decreased expression of IL-10 in the rat colon mucosa (P < 0.01). Treatment with Changyanqing decoction resulted in a significant reduction in DAI, CMDI, HS score and MPO activity (P < 0.01), and decreased the expression of ICAM-1 (P < 0.01) and increased the expression of IL-10 (P < 0.01) in the colon mucosa. The expression of ICAM-1 in the colon mucosa was positively correlated to that of IL-10 (r = 0.927, P < 0.01) and the activity of MPO (r = 0.621, P < 0.01).
Conclusions: Changyanqing decoction has protective effect against rat ulcerative colitis, mediated probably by enhancement of IL-10 expression and reduction in ICAM-1 expression and neutrophil infiltration.