Beta-carotene prevents ozone-induced proinflammatory markers in murine skin.
Beta-carotene has been thought to protect against oxidative stress generated by ultraviolet radiation and thus prevents skin cancer and skin aging (Biesalski and Obermueller-Jevic, 2001). However, nothing is known about its potential effects against other environmental sources of oxidative stress such as ozone (O3) in skin. Intake of oral beta-carotene supplements before exposure to sunlight (and thus inevitably also to (O3) has been recommended on a population-wide basis. However, although some studies have shown beta-carotene as providing skin protection as an antioxidant, other studies using skin cells in culture have shown that beta-carotene may have unexpected prooxidant properties (Obermüller-Jevic, et al., 2001). Given this, there is an ongoing debate regarding the protective or potentially harmful role(s) of beta-carotene in human skin. In this study, the effect of beta-carotene on ozone's effects on the skin of hairless mice was assessed. After feeding a diet supplemented with 0.5% beta-carotene for 1 month, mice were subjected to O3 exposure (0.8 ppm 6 h/day; 7 days) and the induction of proinflammatory markers such as tumor necrosis factor-alpha (TNFalpha), macrophage inflammatory protein 2 (MIP2), and inducible nitric oxide synthase (iNOS), and markers of oxidative stress, heme-oxygenase-1 (HO-1), were quantitated. The data showed that beta-carotene downregulated the induction of TNFalpha, MIP2, iNOS, and HO-1 in response to O3. We conclude that beta-carotene provides protection against O3-induced skin oxidative stress in vivo, which is consistent with a protective role for beta-carotene in the skin.
Valacchi
G
G
Department of Biomedical Sciences, University of Siena, via Aldo Moro, Siena, Italy. valacchi8@unisi.it
Pecorelli
A
A
Mencarelli
M
M
Maioli
E
E
Davis
P A
PA
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D015415:Biomarkers / Q000378:metabolism; D054426:Chemokine CXCL2 / Q000096:biosynthesis; D002851:Chromatography, High Pressure Liquid; D003872:Dermatitis / Q000378:metabolism*; D019587:Dietary Supplements; D005260:Female; D051547:Heme Oxygenase-1 / Q000096:biosynthesis; D051379:Mice; D008812:Mice, Hairless; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis; D018384:Oxidative Stress; D010126:Ozone / Q000633:toxicity*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000187:drug effects* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D019207:beta Carotene / Q000494:pharmacology*
D000975:Antioxidants; D015415:Biomarkers; D054426:Chemokine CXCL2; C404915:Cxcl2 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D019207:beta Carotene; D010126:Ozone; D052247:Nitric Oxide Synthase Type II; D051547:Heme Oxygenase-1