Understanding Exosomes in Hair Regeneration

Abstract Background Alopecia is a prevalent condition correlated with significant psychosocial challenges, while contemporary treatments exhibit variable efficacy, require extended use, and may cause adverse effects. This review aimed to comprehensively assess exosome‐mediated interventions as a novel cell‐free regenerative approach for hair regeneration across multiple alopecia subtypes. Methods A narrative‐scoping review was performed utilizing PubMed, Scopus, and Web of Science databases, identifying 80 preclinical and clinical studies. Eligible studies evaluated exosome‐based mechanisms, delivery systems, and treatment outcomes in hair regeneration without restriction on publication year. Results Exosomes derived from diverse origins (mesenchymal stem cells, hair follicle cells, blood, and plant‐mediated platforms) consistently enhanced hair regeneration via stimulating the Wnt/β‐catenin pathway, promoting VEGF‐regulated angiogenesis, and suppressing TGF‐β/SMAD‐mediated fibrosis and immune‐regulated follicular injury. Preclinical studies showed expedited telogen‐to‐anagen shift, increased follicular proliferation, and enhanced hair shaft properties. Clinical evidence from 11 studies (>330 patients) showed significant increases in hair density (25–35 hairs/cm 2 ), shaft thickness, and patient satisfaction, with impacts sustained up to 1 year. Novel delivery approaches, including microneedles and hydrogels, further improved treatment efficacy. Reported side effects were transient and mild. Conclusion Exosome‐mediated interventions represent a promising, biologically targeted strategy for alopecia treatment, providing immunoregulatory and regenerative advantages superior to traditional approaches. Nonetheless, standardization of manufacturing, regulatory approval, and large‐scale randomized controlled trials are needed before routine clinical application.