Major approaches and clinical studies of the relationship of inflammatory bowel diseases with nutrients, gut microbiota, and exosomes/microRNAs: a systematic review

Abstract

Introduction: Inflammatory bowel diseases (IBDs) are multifactorial diseases characterized by chronic inflammation of the gastrointestinal tract. Nutrients, gut microbiota, exosomes, and microRNAs play crucial roles in the pathophysiology of IBD. Objective: It was to carry out a systematic review of the main approaches and clinical studies on the relationship between inflammatory bowel diseases and nutrients, intestinal microbiota, and exosomes/microRNAs. Methods: The PRISMA Platform systematic review rules were followed. The search was carried out from August to September 2023 in the Web of Science, Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 177 articles were found, and 58 articles were evaluated in full, and 30 were included and developed in the present systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 06 studies with a high risk of bias and 25 studies that did not meet GRADE and AMSTAR-2. Most studies showed homogeneity in their results, with X2=67.7%>50%. It was concluded that inflammatory bowel diseases are associated with various gastrointestinal symptoms and, therefore, affect patients' quality of life. Although intestinal bacteria and the host's immune response are considered important factors in its pathogenesis, a sufficient explanation of their role in its pathophysiological mechanism has not been presented. Exosomes and microRNAs, together with nutrients and gut microbiota, participate in the molecular interactions of inflammatory bowel diseases. Recent studies have confirmed the important role of miRNAs in targeting certain molecules in signaling pathways that regulate intestinal barrier homeostasis, inflammatory reactions, and autophagy of the intestinal epithelium. Several studies have identified specific miRNAs associated with inflammatory bowel diseases in colon tissues. The correlation between the gut microbiota and cytokines suggests that exosomes and microRNAs can modulate intestinal immunity by influencing the gut microbiota.