Experimental colitis attenuates development of toxin-induced cholangitis in rats

Treatment with Carthamus Tinctorius Injection up-regulates IL-4 expression and down-regulates IL-1β expression in ulcerative colitis in rats

AIM: To investigate the therapeutic effects of Carthamus Tinctorius Injection (CTI) against ulcerative colitis (UC) induced with 2,4,6-trinitrobenzene sulfonic acid (TNBS) in rats and to explore the possible mechanisms involved.

METHODS: Thirty male Wistar rats were randomly divided into a treatment group, a model group, and a normal control group (n = 10 for each group). UC was induced with TNBS in rats in both the treatment group and model group. The treatment group was additionally treated with CTI. At the end of the treatment, colonic mucosal samples were taken to calculate disease activity index (DAI) and observe gross morphology of the colon and tissue injury. Colonic mucosal pathological changes were observed by HE staining. The expression of interleukin-4 (IL-4) and IL-1β mRNAs and proteins in colon tissue was detected by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC).

RESULTS: Compared to the model group, the DAI and gross morphology and pathological changes in colon tissue were significantly improved in the treatment group (all P < 0.05). The level of IL-4 in the treatment group was significantly higher than that in the model group (P < 0.05), but no differences was detected between the treatment group and control group. The level of IL-1β in treatment group and model group was significantly higher than that in control group (P < 0.05), but the level in treatment group was significantly lower than that in model group (P < 0.05).

CONCLUSION: CTI treatment relieved TNBS-induced colitis in rats possibly via mechanism associated with increasing IL-4 expression and decreasing IL-1β expression.