Epigenetic Mechanisms, Assessment and Therapeutics of Epidermal Stem Cells in Skin Aging.

Skin aging is a multifaceted biological process driven by genetic and environmental factors, in which epidermal stem cells (EpSCs) decrease in number and decline in function. Emerging evidence indicates that epigenetic modifications play a crucial regulatory role in the aging process. Therefore, elucidating the epigenetic mechanisms in aging will provide novel avenues for developing strategies to delay aging. In this review, we explore the epigenetic mechanisms regulating EpSCs function, namely DNA methylation (DNAm), histone modifications, noncoding RNA, and their dysregulation and the resulting series of manifestations during aging. Furthermore, we introduce epigenetic clocks such as Horvath's and the skin-specific VisAgeX to quantify these age-related changes, which provide precise biomarkers of biological age, enabling the assessment of both aging progression and therapeutic outcomes. Finally, we summarize emerging interventions targeting these epigenetic disruptions. Advancing these epigenetic modulations holds significant potential for cutaneous antiaging and fostering innovative dermatological treatments.