RESUMEN
BACKGROUND: Intrinsic and extrinsic factors, including ultraviolet irradiation, lead to visible signs of skin aging. OBJECTIVE: We evaluated molecular changes occurring in photoexposed and photoprotected skin of white women 20 to 74 years of age, some of whom appeared substantially younger than their chronologic age. METHODS: Histologic and transcriptomics profiling were conducted on skin biopsy samples of photoexposed (face and dorsal forearm) or photoprotected (buttocks) body sites from 158 women. 23andMe genotyping determined genetic ancestry. RESULTS: Gene expression and ontologic analysis revealed progressive changes from the 20s to the 70s in pathways related to oxidative stress, energy metabolism, senescence, and epidermal barrier; these changes were accelerated in the 60s and 70s. The gene expression patterns from the subset of women who were younger-appearing were similar to those in women who were actually younger. LIMITATIONS: Broader application of these findings (eg, across races and Fitzpatrick skin types) will require further studies. CONCLUSIONS: This study demonstrates a wide range of molecular processes in skin affected by aging, providing relevant targets for improving the condition of aging skin at different life stages and defining a molecular pattern of epidermal gene expression in women who appear younger than their chronologic age.
Asunto(s)
Predisposición Genética a la Enfermedad , Envejecimiento de la Piel/genética , Envejecimiento de la Piel/fisiología , Rayos Ultravioleta/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Dermatosis Facial/genética , Dermatosis Facial/patología , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Envejecimiento de la Piel/patología , Población Blanca , Adulto JovenRESUMEN
Global gene expression profiling provides a useful means to identify key aspects of the skin aging process, and provides information to help develop new skin technologies. Important aspects of skin aging that can be addressed include skin hydration, barrier, matrix, pigmentation and antioxidant capacity. Human skin equivalent cultures allow topical application of test compounds, combinations and products to their stratum corneum surface and measurement of predictive biomarkers. Using this in vitro biomarker approach, it is possible to detect skin barrier enhancement in response to the compounds niacinamide and hexamidine, matrix effects to the peptides Pal-KT and Pal-KTTKS, and hydration and matrix responses to niacinamide and N-acetylglucosamine.
