Ulcerative colitis indoleamine 2,3-dioxygenase enzym activity in animal model study

Inflammatory bowel diseases, including both ulcerative colitis and Crohns disease, are complex, chronic, immune-mediated inflammatory disorders of gastrointestinal tract. Their etiologies have not been completely understood however environmental factors, genetic predisposition and immunological factors are thought to have important contributions. İndoleamine 2,3-dioxygenase having immunoinflammatory effects is the rate limiting enzyme of the kynurenine pathway.We evaluated the effects of TNF- inhibitor, infliximab, and poly (ADP-ribose) polymerase (PARP) inhibitor, 3-aminobenzamide on the serum IDO enzyme acitivity and enzyme protein levels of colon tissue in rat colitis induced by trinitrobenzene sulfonic acid. Kynurenine/tryptophan ratio as a serum IDO activity and IDO protein levels of colon tissues did not show statistically significant difference among treatment groups, non-treated colitis and control groups. TNF- levels were significantly increased in colitis group, 3-aminobenzamide group and 3-aminobenzamide plus infliximab group. Only decreased TNF- levels were observed only after infliximab treatment group compared to control group. These results showed that infliximab and/or 3-aminobenzamide treatment did not change IDO activity and levels in TNBS-induced colitis in rat.