Exosomes and microRNAs: Molecular Mediators Linking Obesity, Exercise, and Metabolic Regulation

PURPOSE OF REVIEW: Obesity is a global health crisis characterized by chronic inflammation and metabolic dysfunction, partly driven by altered intercellular communication within the adipose tissue. Exosomes, small extracellular vesicles, and their microRNA (miRNA) cargo have emerged as key mediators in this process, facilitating crosstalk between adipose tissue and other organs and influencing insulin sensitivity, inflammation, and energy homeostasis. Physical exercise modulates the expression and secretion of exosomal miRNAs, contributing to systemic metabolic improvements and counteracting obesity-related diseases. This study reviews recent research on the causal role of exosomes in obesity-related metabolic dysfunction. RECENT FINDINGS: Exosome-derived miRNAs are often deregulated in obese individuals, promoting adipose tissue hypertrophy, systemic insulin resistance, and chronic inflammation. Specific miRNAs (e.g., miR-34a, miR-29a, miR-222, miR-155, and miR-27a) have been implicated in impairing insulin signaling and promoting pro-inflammatory states. Exercise-induced exomiRs (e.g., miR-1, miR-133b, and miR-22) mediate beneficial effects, such as enhanced lipolysis, improved insulin sensitivity, and reduced inflammation. Experimental models have shown that exosomes from trained animals can transfer these benefits to their sedentary or obese counterparts. Exosomes and their miRNA cargoes are crucial mediators of crosstalk between adipose tissue and other organs, significantly influencing metabolic regulation in obesity. Physical exercise is a potent modulator of exosome-mediated signaling, offering systemic metabolic benefits and potential non-pharmacological interventions.