Evaluation of imunnomodulation induced by crotoxin isolated from Crotalus durissus terrificus in experimental model of inflammatory bowel disease

Abstract

Mechanisms of immune tolerance are related to mucosal protection against pathogens or antigens from the intestinal microbiota. When failure occurs in the regulation of immune system diseases may arise as the intestinal inflammation. Crohn's disease and ulcerative colitis are the main examples of these pathologies causing rectal bleeding, severe diarrhea, abdominal pain, fever, fatigue and weight loss. In Crohn's disease there is an exacerbated immune response, mainly mediated by Th1 cells and may also have the participation of Th17, whereas in ulcerative colitis there is a predominance of Th2 cells. However, the factors involved in triggering inflammation of the intestinal mucosa are not yet clearly established. Experimental models of intestinal inflammation induced by chemical agents such as trinitrobenzene sulfonic acid (TNBS) are therefore extremely useful for understanding these diseases and the search for effective therapies in controlling these reactions. The crotoxin (CTX) is the main component of the venom of the rattlesnake Crotalus durissus terrificus and among its biological activities, there is its immunosuppressive effect. Studies in our laboratory allowed the observation that this toxin is able to inhibit cellular and humoral responses and also that IL-10 is involved in this process. According to this information, the purpose of this project is to evaluate the effect of crotoxin in the experimental model of acute and chronic intestinal inflammation TNBS-induced mice. Thus, we found in preliminary experiments that administration of crotoxin after induction of acute intestinal inflammation was able to inhibit weight loss and diarrhea in the animals studied.