Intestinal anti-inflammatory activity of the 'Serpylli herba' extract in experimental models of rodent colitis

Introduction: Nowadays, there is an increasing interest for alternative options in the treatment of inflammatory bowel diseases (IBDs) that combine efficacy and an adequate safety profile. Methods: The intestinal anti-inflammatory effects of Serpylli herba, the officinal drug in the European Pharmacopeia composed by the aerial parts of wild thyme (Thymus serpyllum), were evaluated in the trinitrobenzenesulfonic acid (TNBS)-induced rat colitis and dextran sodium sulfate (DSS)-induced mouse colitis, which are well characterized experimental models with some resemblance to human IBD. Results: S. herba extract exerted an intestinal anti-inflammatory effect in both experimental models of colitis, as evidenced both histologically, since it facilitated the tissue recovery of the damaged colon, and biochemically as showed by the improvement of the different inflammatory markers evaluated, including myeloperoxidase activity, glutathione content, and leukotriene B4 levels as well as the expression of the inducible proteins iNOS and COX-2. This beneficial effect was associated with the reduction in the expression of different cytokines, like TNFα, IL-1β, IFN╬│, IL-6 and IL-17, the chemokine MCP-1, and the adhesion molecule ICAM-1, thus ameliorating the altered immune response associated with the colonic inflammation. Conclusion: S. herba extract displays an anti-inflammatory effect on different models of rodent colitis that could be attributed to its immunomodulatory properties.