Research Progress of Exosome-Derived microRNA in Alcohol Use Disorders: A Critical Review.

Alcohol use disorder (AUD) is a chronic, relapsing condition that causes extensive systemic damage, yet clinically actionable biomarkers remain lacking. Exosome-derived microRNAs (exo-miRNAs) have emerged as highly stable extracellular indicators of disease state and active regulators of alcohol-induced pathological processes. Unlike proteins or lipids, miRNAs are selectively packaged, cell-type specific and mechanistically linked to inflammation, hepatocellular injury, synaptic dysfunction and neuroimmune signalling. Here, we provide an integrated and updated review of how chronic alcohol exposure reshapes exo-miRNA cargo across organs-particularly the liver, immune system and central nervous system. We summarize the biogenesis and selective sorting of exo-miRNAs, highlight key candidate miRNAs such as miR-122, miR-155, miR-192, miR-29a, miR-30a and miR-124 and analyse their representative gene targets and downstream effects. Furthermore, we distinguish exo-miRNAs with diagnostic potential from those representing promising therapeutic targets and discuss major limitations, including specificity relative to other drugs of abuse. By integrating mechanistic and translational evidence, this review aims to clarify the biological and clinical value of exo-miRNAs and to provide guidance for future precision-medicine strategies in AUD.