UV light, beta-carotene and human skin--beneficial and potentially harmful effects.
Solar radiation is one of the most important environmental stress agents for human skin, causing sunburn, premature skin aging, and skin cancer. Beta-carotene is discussed to protect against photooxidative stress and thus prevent skin damage. Though beta-carotene has been successfully used against photosensitivity in patients with erythropoietic protoporphyria, its beneficial potential in normal skin is still uncertain. A number of experimental studies indicate protective effects of beta-carotene against acute and chronic manifestations of skin photodamage. However, most clinical studies have failed to convincingly demonstrate its beneficial effects so far. Nevertheless, intake of oral beta-carotene supplements before sun exposure has been recommended on a population-wide basis. Recent studies on skin cells in culture have revealed that beta-carotene acts not only as an antioxidant but also has unexpected prooxidant properties. At present, there is an ongoing debate on the protective or potentially harmful role of beta-carotene in human skin.
Biesalski
H K
HK
Department of Biological Chemistry and Nutrition, University of Hohenheim, Stuttgart, Germany. biesal@uni-hohenheim.de
Obermueller-Jevic
U C
UC
D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D006419:Heme Oxygenase (Decyclizing) / Q000378:metabolism; D051547:Heme Oxygenase-1; D006801:Humans; D008565:Membrane Proteins; D018384:Oxidative Stress / Q000187:drug effects / Q000528:radiation effects; D018570:Risk Assessment; D012867:Skin / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D015595:Skin Aging / Q000187:drug effects; D014466:Ultraviolet Rays / Q000009:adverse effects*; D019207:beta Carotene / Q000378:metabolism / Q000494:pharmacology*
D008565:Membrane Proteins; D019207:beta Carotene; C496541:HMOX1 protein, human; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1