Effect of Yoghurt on the Cytokine Profile using a Murine Model of Intestinal Inflammation

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, are important problems in industrialized countries. The complete aetiology of both diseases is still unknown but likely involves genetic, environmental and immunological factors. The aim of this work is to study the anti-inflammatory mechanisms reported for yoghurt in a colon cancer model in order to evaluate its usefulness in the treatment of intestinal inflammation such as Crohn's disease. A trinitrobenzenesulfonic acid (TNBS)-induced colitis model was used. The influence of yoghurt feeding was studied before and after TNBS inoculation. The effect on the intestinal microbiota and on the host immune response was evaluated. IgA-producing cells and cells positive for specific cytokines (IL-12, IL-17, IFNγ and IL-10) were analyzed. Yoghurt administration diminished the severity of inflammation in the TNBS-inoculated mice. This effect occurred mainly through IL-10, which was increased in the intestinal tissues throughout the study, and by the decrease observed in IL-17 and IL-12 levels. In addition to this immunomodulatory capacity, another mechanism by which yoghurt could exert the anti-inflammatory activity observed in our model would be through beneficial changes in the intestinal microbiota (increases in the bifidobacteria and lactobacilli populations). These changes in the intestinal microbiota could also be considered one of the causes of the intestinal inflammation reduction. These results show that yoghurt administration modulated the immune response, inducing down regulation of the inflammatory cytokines produced by the immune cells involved in the inflammatory process. The protective effect