Gut microbiota and skeletal muscle axis in sports performance through nutrological activation of irisin and microRNAs: a systematic review

Introduction: Several discoveries have accumulated evidence regarding gut microbiota, regenerative nutrition, and skeletal muscle metabolism. Exercise volume and intensity have been shown to influence gastrointestinal health status, including the role of growth factors, signaling pathways, oxidative stress, metabolic factors, irisin, and microRNAs. Objective: To present, through a systematic review, the main approaches and outcomes of clinical studies of the gut microbiota and skeletal muscle axis in sports performance through the nutritional activation of irisin and microRNAs. Methods: The PRISMA Platform systematic review rules were followed. The research was carried out from January to April 2024 in the 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: 121 articles were found. A total of 40 articles were evaluated in full and 19 were included and developed in the present systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 16 studies with a high risk of bias and 25 studies that did not meet GRADE. It was concluded that exercise-induced stimulation of irisin (bioactive cytokines), through muscle-bone-fat crosstalk, increases muscle anabolism, bone formation, mitochondrial biogenesis, glucose utilization, and fatty acid oxidation and Attenuates chronic low-grade inflammation. A current focus in the field of sports and metabolism is the investigation of how specific metabolites and nutrients affect the progression and treatment of muscle injuries. Nutrients can also regulate normal homeostatic processes by altering the decisions of muscle stem and satellite cells. MicroRNAs have emerged as important players in the regulation of gene expression, being involved in most of the biological processes examined to date, given that microRNAs are mainly involved in the cell's stress response making them ideal candidates for mediating the skeletal muscle response to changes in contractile activity. Identifying and validating target genes will help understand the molecular mechanism through which microRNAs regulate skeletal muscle in response to exercise.