Progress in the Application of Exosomes in Androgenetic Alopecia: Focusing on Molecular Mechanisms.

Androgenetic alopecia (AGA) is the most common type of hair loss worldwide, characterized by progressive miniaturization of hair follicles and a shortened anagen phase. Currently, FDA-approved drugs for AGA treatment, minoxidil and finasteride, cannot provide satisfactory outcomes for all patients and can sometimes cause side effects. Therefore, there has been an urgent need for novel and safer therapeutic strategies. At the cellular and molecular level, the pathogenesis of AGA is closely associated with the dysregulation of signaling pathways in hair follicles. As nano-sized extracellular vesicles secreted by cells, exosomes carry bioactive substances such as proteins, lipids, and nucleic acids, thereby playing a crucial role in intercellular and intracellular communication. By modulating dysregulated signaling pathways in hair follicles, exosome therapy offers a highly promising therapeutic option for AGA patients. However, it should be noted that current evidence remains limited, and more well-designed studies are required to validate the long-term efficacy and safety of exosome-based therapies for AGA. Also, addressing challenges in the production, application, and regulation of exosomes is indispensable for promoting the future clinical application of exosome-based therapies in AGA treatment. This review summarizes the preclinical and clinical progress in exosome-based therapies for AGA treatment, with a particular focus on their molecular mechanisms, especially their regulation of key signaling pathways involved in AGA pathogenesis, such as Wnt/β-catenin, Shh, TGF-β/Smad, PI3K/AKT, and MAPK signaling pathways. These endeavors are expected to provide researchers with valuable scientific insights and practical information for AGA drug discovery.