Beta-carotene inhibits UVA-induced matrix metalloprotease 1 and 10 expression in keratinocytes by a singlet oxygen-dependent mechanism.
Free Radic Biol Med
; 37(5): 654-70, 2004 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-15288123
ABSTRACT
UVA exposure causes skin photoaging by singlet oxygen (1)O(2)-mediated induction of, e.g., matrix metalloproteases (MMPs). We assessed whether pretreatment with beta-carotene, a (1)O(2) quencher and retinoic acid (RA) precursor, interferes with UVA-induced gene regulation. HaCaT keratinocytes were precultured with beta-carotene at physiological concentrations (0.5, 1.5, and 3.0 microM) prior to exposure to UVA from a Hönle solar simulator (270 kJ/m(2)). HaCaT cells accumulated beta-carotene in a time- and dose-dependent manner. UVA irradiation massively reduced the cellular beta-carotene content. Beta-carotene suppressed UVA-induction of MMP-1, MMP-3, and MMP-10, three major matrix metalloproteases involved in photoaging. We show that regulation by not only MMP-1, but also MMP-10, involves (1)O(2)-dependent mechanisms. Beta-carotene dose-dependently quenched (1)O(2)-mediated induction of MMP-1 and MMP-10. Thus, as in chemical solvent systems, beta-carotene quenches (1)O(2) also in living cells. Vitamin E did not cooperate with beta-carotene to further inhibit MMP induction. HaCaT cells produced weak retinoid activity from beta-carotene, as demonstrated by mild upregulation of RAR beta and activation of an RARE-dependent reporter gene. Beta-carotene did not regulate the genes encoding other RARs, RXRs, or the two beta-carotene cleavage enzymes. These results demonstrate that beta-carotene acts photoprotectively, and that this effect is mediated by (1)O(2) quenching.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Luz Solar
/
Raios Ultravioleta
/
Metaloendopeptidases
/
Queratinócitos
/
Beta Caroteno
/
Metaloproteinase 1 da Matriz
/
Oxigênio Singlete
/
Antioxidantes
Limite:
Humans
Idioma:
En
Revista:
Free Radic Biol Med
Assunto da revista:
BIOQUIMICA
/
MEDICINA
Ano de publicação:
2004
Tipo de documento:
Article
País de afiliação:
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