The effects of Gefarnate in treatment of rat model of colitis induced by trinitrobenzene sulphonic acid / 中华消化杂志

ABSTRACT

Objective To investigate the effects of Gefarnate on expression of myeloperoxidase (MPO),cyelooxygenase-1 (COX-1) and COX-2 in trinitrobenzene sulphonic acid (TNBS) induced experimental colitis in rats and its therapeutic effects on ulcerative colitis. Methods Forty female Sprague-Dawley (SD) rats were randomly divided into 4 groups with 10 each. The rats in group A, B and C were infused with TNBS/alcohol by enema. After the production of colitis, the rats in group A or B were treated daily with 1 ml of normal saline or with 1 ml of 5-ASA (100 mg/kg) by enema,and those in group C were treated daily with 1 ml of Gefarnate by gavage. Group D was served as normal control. After the production of colitis,animals were sacrificed at day 7 and 14 with 5 in each group. The macroscopic changes of the colon were evaluated according to disease activity index (DAD scoring and histological change was assessed by HE staining. MPO activity of the mucosa was detected by biochemical methods. Expressions of COX-1 and COX-2 in tissues were detected by immunohistochemistry. Results Compared with group A, macroscopic and histological scores and MPO activity were significantly decreased in group B and C (P<0.05). The expressions of COX-1 at day 7 and 14 were 1.86±0.51 and 1.96±0.41 in group B, 1.73±0.68 and 1.79±0.6 in group C, 1.91±0.34 and 1.99±0.45 in group D, respectively, which were significantly higher than those in group A (0.87±0.18 and 0.93±0.15, P<0.05). Whereas the expressions of COX-2 at day 7 and 14 were 1.53±0.19 and 0.73±0.15 in group B, 1.73±0.94 and 0.86±0.29 in group C, 0.24±0.18 and 0.18±0. 16 in group D, respectivley, which were significantly lower that those in group A (3.50±0.2;3 and 3.06±0.27). There was a significant difference between group D and group B or C (P<0.05). Conclusions Gefarnate provides a therapeutic effect during TNBS-induced colitis in rats, which is similar to that of 5-ASA. The mechanisms are involved in decreasing the concentration of colonic MPO and regulating the expression of COX-1/COX-2.