Vitamin C, gene expression and skin health

Abstract

Vitamin C (ascorbic acid) is an essential micronutrient, required for multiple biological functions. In this chapter, we review in vitro and in vivo evidence that vitamin C plays an important role in skin biology, contributing to the formation of efficient skin barrier and to fibroblast proliferation/ migration during wound healing. Vitamin C is also widely used in cosmetic and dermatological products since it is reported to have a number of beneficial effects on the skin. As an antioxidant it can scavenge deleterious free radicals and other oxidizing species that contribute to the process of skin aging. By stimulating collagen synthesis it improves the elasticity of the skin, thereby reducing fine lines and wrinkles. Furthermore, its ability to suppress skin pigmentation makes it a useful whitening agent. Ascorbic acid is, however, an unstable compound in aqueous solution, and several water- and lipid-soluble derivatives were synthesized to improve stability and increase skin penetration. The effectiveness of different ascorbic acid derivatives that are currently employed in dermatological preparations and cosmetics, in particular magnesium L-ascorbyl-2-phosphate and ascorbyl palmitate, is discussed. Finally, we compare the efficacy of different routes of administration of vitamin C, alone or in combination with other antioxidants, with a focus on newly developed topical delivery systems.