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Photobiological implications of melanin photoprotection after UVB-induced tanning of human skin but not UVA-induced tanning.

ABSTRACT: Repetitive suberythemal UVA and/or UVB exposures were used to generate comparable UV-induced tans in human skin over the course of 2 weeks. To evaluate the potential photoprotective values of those UVA- and/or UVB- induced tans and to avoid the confounding issue of residual UV-induced DNA damage, we waited 1 week before challenging those areas with a 1.5 MED of UVA+UVB after which we measure DNA damage. The results show that the type of UV used to induce skin pigmentation affects the redistribution of melanin in the skin and/or de novo melanin synthesis. The UVA-induced tans failed to even provide a minimal SPF of 1.5, which suggests that producing a tan with UVA-rich sunlamps prior to a holiday or vacation is completely counterproductive.

SUBMITTER: Coelho SG

PROVIDER: S-EPMC4333058 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Photobiological implications of melanin photoprotection after UVB-induced tanning of human skin but not UVA-induced tanning.

Coelho Sergio G SG Yin Lanlan L Smuda Christoph C Mahns Andre A Kolbe Ludger L Hearing Vincent J VJ

Pigment cell & melanoma research 20150105 2

Repetitive suberythemal UVA and/or UVB exposures were used to generate comparable UV-induced tans in human skin over the course of 2 weeks. To evaluate the potential photoprotective values of those UVA- and/or UVB- induced tans and to avoid the confounding issue of residual UV-induced DNA damage, we waited 1 week before challenging those areas with a 1.5 MED of UVA+UVB after which we measure DNA damage. The results show that the type of UV used to induce skin pigmentation affects the redistribut ...[more]

PMID: 25417821

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