BACKGROUND Reactive oxygen species generated by ultraviolet light result in photocarcinogenic and photoaging changes in the skin. Antioxidants protect skin from these insults. OBJECTIVE This study defines formulation characteristics for delivering L-ascorbic acid into the skin to supplement the skin's natural antioxidant reservoir. METHODS L-ascorbic acid or its derivatives were applied to ...

Ultraviolet (UV) radiation-induced loss of dermal extracellular matrix is associated with skin photoaging. Recent studies demonstrated that keratinocyte-releasable stratifin (SFN) plays a critical role in skin collagen metabolism by inducing matrix metalloproteinase 1 (MMP1) expression in target fibroblasts. In the present study, we examined whether SFN released from UVB-irradiated epidermal ke...

Photochemoprevention has become an important armamentarium in the fight against ultraviolet radiation induced damage to the skin. UV irradiation to skin results in erythema, edema, sunburn cells, hyperplasia, immunosuppression, photoaging and photocarcinogenesis. Various synthetic agents have been used as photoprotectives but they have limited use because of their potential toxicity in humans a...

Research conducted during the past 25 years has produced an understanding of the mechanisms that lead to connective tissue damage during chronological aging and as a result of chronic, repetitive exposure to ultraviolet (UV) radiation from the sun. While the etiologies of these two conditions are distinct, they share common pathophysiological mechanisms. In both conditions, upregulation of coll...

With worldwide expansion of the aging population, research on age-related pathologies is receiving growing interest. In this review, we discuss current knowledge regarding the decline of skin structure and function induced by the passage of time (chronological aging) and chronic exposure to solar UV irradiation (photoaging). Nearly every aspect of skin biology is affected by aging. The self-ren...