THE ROLE OF VITAMIN-E IN NORMAL AND DAMAGED SKIN

The generation of free oxygen radicals is believed to play an importan t pathogenic role in the development of various disorders. More than o ther tissues, the skin is exposed to numerous environmental chemical a nd physical agents such as ultraviolet light causing oxidative stress. In the skin this results in several short- and long-term adverse effe cts such as erythema, edema, skin thickening, wrinkling, and an increa sed incidence of skin cancer or precursor lesions. However, accelerate d cutaneous aging under the influence of ultraviolet light, usually te rmed photoaging, is only one of the harmful effects of continual oxyge n radical production in the skin. Others include cutaneous inflammatio n, autoimmunological processes, keratinization disturbances, and vascu litis. Vitamin E is the major naturally occurring lipid-soluble non-en zymatic antioxidant protecting skin from the adverse effects of oxidat ive stress including photoaging. Its chemistry and its physiological f unction as a major antioxidative and anti-inflammatory agent, in parti cular with respect to its photoprotective, antiphotoaging properties, are described by summarizing animal studies, in vivo tests on human sk in and biochemical in vitro investigations. The possible therapeutic u se in different cutaneous disorders, and pharmacological and toxicolog ical aspects are discussed. Many studies document that vitamin E occup ies a central position as a highly efficient antioxidant, thereby prov iding possibilities to decrease the frequency and severity of patholog ical events in the skin. For this purpose increased efforts in develop ing appropriate systemic and local pharmacological preparations of vit amin E are required.