The Role of Mesenchymal Stem Cell-Derived Exosomes in Skin Moisturization and Repair: A Review

Extracellular vesicles (EVs), especially exosomes derived from Mesenchymal Stem Cells (MSC-exosomes), are an innovative cell-free approach to improving skin health. The skin serves as the main barrier to the body and is compromised due to aging and environmental stressors. Topical therapies can be used; however, these therapies have minimal effects. This review provides an in-depth review on MSC-exosomes with respect to the role they may play in skin moisturization and repair. MSC-exosome biogenesis and their bioactive cargo are explained. MSC-exosomes contain a unique bioactivity such as a vast combination of growth factors, immunomodulatory cytokines, lipids (including ceramides), and microRNAs; collectively, these are able to induce skin rejuvenation. The complex mechanisms of action are detailed, focusing on ameliorating the epidermal barrier by synthesising Natural Moisturising Factors (NMF) and lipids, alongside remodeling the dermal extracellular matrix through the stimulation of collagen synthesis via pathways such as PI3K/Akt. The methodologies for isolating and characterising exosomes are also detailed, and the importance of standardization for clinical use is discussed. Preclinical studies have shown promise, but issues relating to GMP-produced exosomes and regulatory hurdles need to be addressed before full implementation in the healthcare setting. This review highlights the current state of the research pipeline and the next steps needed in order to realise the full therapeutic and cosmetic potential of MSC-exosomes to dermal health.