Skin Aging: From Molecular Mechanisms to Therapeutic and Technological Innovations.

Aging is a complex, pervasive biological process that causes irreversible declines in function across organ systems. The skin, the body's largest organ, interfaces directly with the external environment and undergoes aging driven by intrinsic (chronological) and extrinsic (environmental) factors, which result in functional deterioration and greater susceptibility to related disorders. Although numerous anti-aging strategies have been investigated, relatively few specifically target the skin. This review delineates the principal phenotypes and underlying mechanisms of skin aging. Phenotypic hallmarks include reduced regenerative capacity, chronic inflammation and impaired barrier function, whereas key mechanisms comprise oxidative stress, DNA damage, paracrine induction of cellular senescence(definition) and epigenetic alterations. The review evaluates recent research advances and associated clinical challenges in mitigating skin aging, with particular emphasis on pharmacological interventions and stem cell therapy. Finally, it briefly reviews delivery systems for natural anti-aging compounds and explores the potential of artificial intelligence (AI) to accelerate novel drug discovery.