Mini-Review: the gut microbiota-muscle axis and its role in aging research

BACKGROUND: Aging is a multifactorial process, one of whose key consequences is the decline in muscle strength and mass, which directly impacts the functional capacity of older adults. One possible mechanism involved in this process is the role of gut microbiota in muscle atrophy. AIM: To explore the role of the gut microbiota-muscle axis during aging, investigating its relationship with functional outcomes and the potential for intervention. METHOD: A mini-review of the literature was conducted using the PubMed, Scopus, and Embase databases with the keywords “microbiota”, “microbiome”, “gut-muscle axis”, “aging” and “muscle”. RESULTS: Aging affects the gut microbiota, notably its bacterial composition (with increases in Proteobacteria, Clostridium, and Enterococcus), along with an increased release of lipopolysaccharides and a reduction in short-chain fatty acid production. These changes are linked to signaling pathways involved in muscle atrophy. Despite evidence showing how the gut microbiota-muscle axis influences muscle mass loss during aging, the direct relationship with functional capacity remains limited. However, physical training and diet are non-pharmacological interventions that can modify the gut microbiota. CONCLUSION: The mechanisms underlying the gut microbiota-muscle axis present opportunities for further investigation into aging health and motor performance, particularly concerning nutrition and physical training.