Modulation of NLRP3 Inflammasome Attenuated Inflammatory Response Associated to Diarrhea-Predominant Irritable Bowel Syndrome.

Diarrhea-predominant irritable bowel syndrome (IBS-D) is a multifactorial chronic gastrointestinal disorder characterized by inflammation and immune response. In this context, NLRP3 over-activation is associated with a breakdown of enteric-immune balance related to IBS-D. The aim of this study was to evaluate the effect of the inflammasome inhibitor, BAY 11-7082, in a rat model of IBS-D. Syndrome was induced by intracolonic instillation of 1 mL 4% acetic acid at 8 cm proximal to the anus for 30 s and sacrificed 2 weeks after IBS-D induction. BAY 11-7082 (10 and 30 mg/kg) was administered daily by oral gavage. The results obtained showed that the treatment with BAY 11-7082 (30 mg/kg) significantly reduced tissue injury characterized by edema, neutrophil infiltration, and loss of colon structure. We demonstrated that BAY 11-7082 treatment inhibited NLRP3 inflammasome activation and NF-kB translocation, reducing inflammatory mediators. Moreover, treatment with BAY 11-7082 restored tight junction alteration following IBS-D induction and reduced the restraint stress. Taken together, our data demonstrate that IBS-D induced NLRP3 inflammasome pathway activation, accompanied by the production of proinflammatory response. The modulation of the inflammosome pathway with BAY 11-7082 inhibitor significantly reduced pathological signs of IBS-D, therefore, can be considered a valuable strategy to reduce the development of IBS-D.