Unveiling exosomes in combating skin aging: insights into resources, mechanisms and challenges.

Skin ageing is a multifactorial process influenced by both intrinsic (genetic and metabolic) and extrinsic (environmental) factors, leading to noticeable changes such as wrinkles, loss of elasticity, and pigmentation disorders. Recent advancements in regenerative medicine have highlighted the potential of exosomes, small extracellular vesicles, in mediating cellular communication and promoting rejuvenation processes in skin tissues. Exosomes are secreted by various cell types and are rich in bioactive molecules such as proteins, lipids, and nucleic acids, which are crucial for modulating physiological responses. Exosomes derived from mesenchymal stem cells (MSCs), adipose-derived stem cells (ADSCs), and other sources have shown promising results in enhancing skin cell proliferation and collagen synthesis and reducing oxidative stress, thereby mitigating both intrinsic and extrinsic skin ageing. Therefore, this review explores the mechanisms through which exosomes exert their effects, including the modulation of signalling pathways involved in cell growth, anti-inflammatory responses, and matrix remodelling. We also explore innovative delivery systems for exosome-based therapies, such as microneedling and hydrogels, which enhance the penetration and efficacy of these vesicles in skin applications. However, despite their potential, the clinical application of exosome-based therapies faces challenges such as scalability of production, standardization of purification methods, and understanding of long-term effects. This comprehensive investigation emphasised the potential of exosomes in the fields of dermatology and regenerative medicine in combating skin ageing.