Major considerations of nutrological aspects, gut microbiota, and regulation (down or up-regulation) of microRNAs/exosomes in inflammatory bowel diseases: a systematic review

Introduction: Inflammatory bowel diseases (IBD) are multifactorial, chronic, continuous, relapsing, and immune-mediated diseases of the gastrointestinal tract. The pathogenesis of IBD is linked to genetically susceptible individuals, dysregulated gut microbiota (dysbiosis), chronic inflammation, and poor dietary patterns. Diet and microRNAs/exosomes play an important role in modulating the intestinal microbiota, and can be applied as a therapeutic tool to improve the course of IBD. Objective: It was to carry out a systematic review of the main considerations of nutrological aspects, intestinal microbiota, and the regulation (Down or Up-regulation) and modulation of microRNAs/exosomes in inflammatory bowel diseases. Methods: The present study followed the international model of systematic review and meta-analysis (PRISMA). Clinical studies were included, involving randomized controlled, prospective, and retrospective studies, as well as pre-clinical studies, published in previous years as gold standard articles until 2023. Results and Conclusion: A total of 154 articles were found. A total of 78 articles were fully evaluated and 55 were included in this systematic review. Considering the Cochrane tool for risk of bias, 22 studies with a high risk of bias and 24 studies that did not meet the GRADE were removed. Most studies showed homogeneity in their results, with X2 =93.5% >50%. The present study analyzed the main interactions between dietary therapy, intestinal microbiota, microRNAs, exosomes, and inflammatory bowel disease, elucidating the main clinical outcomes of the disease after nutrological treatment. As a corollary, important randomized controlled clinical studies were found in the last ten years that showed the important role of diet modulation in the control and even in the remission of inflammatory bowel disease, revealing important reductions in persistent intestinal symptoms, in the balance of the intestinal microbiota, in the regulatory role of microRNAs, reducing inflammation markers and improving quality of life. Recognition of the need for additional data from clinical trials, the inherent uncertainty of efficacy for all inflammatory bowel disease therapies, and the potential for benefit with dietary interventions will help guide progress toward a better understanding of the usefulness of dietary therapy for individuals with inflammatory bowel disease.