Effects of silymarin on the acute stage of the trinitrobenzenesulphonic acid model of rat colitis

The intestinal anti-inflammatory activity of several doses of silymarin was tested in the acute stage of the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. The results obtained show that oral pre-treatment with 50 mg/kg of silymarin significantly attenuated macroscopic colonic damage as w ell as reduced colonic myeloperoxidase activity compared to nontreated coli tic animals. The beneficial effect was accompanied by an improvement in the colonic oxidative status, which was altered in colonic inflammation, by pr eventing glutathione depletion and reducing malonyldialdehyde production. T his suggests that the well known antioxidant properties of silymarin can pa rticipate in its intestinal anti-inflammatory activity. In addition, a pres ervation in the colonic absorptive function was also observed, and this eff ect can also account for the colonic protective effect observed in this mod el of acute colitis.