Pigmentation effects of solar-simulated radiation as compared with UVA and UVB radiation.
Pigment Cell Melanoma Res
; 21(4): 487-91, 2008 Aug.
Article
em En
| MEDLINE
| ID: mdl-18627527
ABSTRACT
Different wavelengths of ultraviolet (UV) radiation elicit different responses in the skin. UVA induces immediate tanning and persistent pigment darkening through oxidation of pre-existing melanin or melanogenic precursors, while UVB induces delayed tanning which takes several days or longer to develop and requires activation of melanocytes. We compared the effects of a 2-week repetitive exposure of human skin to solar-simulated radiation (SSR), UVA or UVB at doses eliciting comparable levels of visible tanning and measured levels of melanins and melanin-related metabolites. Levels of eumelanin and pheomelanin were significantly higher in the order of SSR, UVB, UVA or unexposed control skin. Levels of free 5-S-cysteinyldopa (5SCD) were elevated about 4-fold in SSR- or UVB-exposed skin compared with UVA-exposed or control skin. Levels of protein-bound form of 5SCD tended to be higher in SSR- or UVB-exposed skin than in UVA-exposed or control skin. Total levels of 5-hydroxy-6-methoxyindole-2-carboxylic acid (5H6MI2C) and 6H5MI2C were higher in SSR- than in UVB-exposed or control skin. These results show that SSR is more effective in promoting delayed tanning than UVB radiation alone, suggesting a synergistic effect of UVA radiation. Furthermore, free 5SCD may serve as a good marker of the effect of SSR and UVB.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Raios Ultravioleta
/
Pigmentação da Pele
Limite:
Adult
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Pigment Cell Melanoma Res
Assunto da revista:
NEOPLASIAS
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Alemanha