The Role of the Microbiota in driving Inflammatory Bowel Disease pathogenesis

Abstract

Inflammatory bowel disease is a chronic intestinal inflammatory disease that encompasses two major human health problems: Ulcerative colitis and Crohn’s disease. Patients with these diseases experience abdominal symptoms, including bloody stools, diarrhea, vomiting, and abdominal pain, which is the result of a dysregulated interaction between host and commensal microbiota in a genetically susceptible individual. Indeed, host health relies on the intestinal homeostasis between the microbiota and the innate, adaptive immune system. Under homeostasis, the microbiota provides the host with essential functions, such as nutrient metabolism, immunomodulation, and protection against pathogens, in turn, the mucosal immune system monitors these microbiotas. However, any slight disturbance in the microbial communities (dysbiosis) resulting from antibiotic exposure, diet, or environment may lead to intestinal immune disruption and increased IBD susceptibility. Moreover, altering microbiota functions such as carbohydrate fermentation may be associated with the dysregulated immune system that causes an inflammatory response. This review provides a comprehensive analysis of the role of the microbiota in driving IBD pathogenesis and demonstrates the available therapeutics, highlighting the potential for manipulation of gut microbiota in IBD therapeutics to manage and prevent the onset of this disease. The current evidence for involving microbiota in IBD pathogenesis will also be discussed. To conclude, several animal and human studies have demonstrated the implication of gut microbiota in IBD pathogenesis after comparison of the microbiota between healthy individuals and those with IBD.