• Publikační typ
• abstrakt z konference MeSH

BACKGROUND: Solar light generates inflammatory responses in exposed skin. These effects are generally attri Buted to UV B light. However, skin is expose d to a huge quantum of UVA photons as UVA is a predominant part of sunlight and the radiation used in tanning Beds. We examined the effects of a single exposure to UVA and UV B wave Bands on cytokine levels in skin and plasma, myeloperoxidase (MPO) activity, expression of induci Ble nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) in skin. METHODS: Hairless mice were irradiated with either UVA (10 or 20 J/cm²) or UV B (200 or 800 mJ/cm²). The effects were assessed after 4/24 h. Plasma cytokine levels were evaluated using a Bio-Plex cytokine assay. Cytokine, iNOS and COX-2 levels in skin were determined By Western Blot. Skin MPO activity was monitored spectrophotometrically. RESULTS: UV B induced up-regulation of interleukin-1β (IL-1β) and interleukin-6 (IL-6) and decrease in interleukin-10 (IL-10) mainly after 4 h. In contrast, UVA caused increase in levels of tumor necrosis factor-alpha (TNF-α) and IL-6 after 4 h and up-regulated IL-10 and interleukin-12 (IL-12) after 24 h. The increase in MPO activity from infiltrated leucocytes was o Bserved only in UV B irradiated animals. iNOS was up-regulated 4 h after UVA and UV B treatment. No significant effect on COX-2 expression was detected. CONCLUSIONS: UVA and UV B light affected several inflammatory markers. For individual wave Band, changes in plasma parameters did not correlate with those in skin. Thus evaluation of plasma samples cannot simply Be replaced By determination in skin specimens and vice versa.

• MeSH
• časové faktory MeSH
• cyklooxygenasa 2 metabolismus   účinky záření   MeSH
• cytokiny * krev   účinky záření   MeSH
• kůže * metabolismus   účinky záření   MeSH
• myši bezsrsté MeSH
• myši MeSH
• peroxidasa metabolismus   účinky záření   MeSH
• spektrofotometrie MeSH
• synthasa oxidu dusnatého, typ II metabolismus   účinky záření   MeSH
• ultrafialové záření škodlivé účinky   MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Solar ultraviolet (UV) radiation is an important risk factor in skin carcinogenesis. This has been attributed mainly to the UVB waveband because the high-energetic photons are capable of interacting with DNA and inducing DNA damage. Recently, UVA light has also gained increasing interest in relation to DNA alteration. Although UVA photons are less energetic than UVB, they comprise a major fraction of sunlight UV radiation and penetrate deep into the skin. The study was carried out to compare the acute effects of UVA and UVB light on SKH-1 mice in relation to DNA damage and associated parameters. Mice were exposed to UVA (10 and 20 J/cm(2)) or UVB (200 and 800 mJ/cm(2)) radiation. The number of DNA single-strand breaks (SSB) in lymphocytes, amount of phosphorylated histone H2AX (gamma-H2AX) and apoptosis or DNA fragmentation (TUNEL-positive cells) in skin sections and level of gamma-H2AX, activated caspase-3 and phosphorylated p53 in skin were evaluated after 4 and 24 h. SSB analyzed by alkaline comet assay were found to be 4 and 24 h following UVB and UVA treatment, respectively. TUNEL and gamma-H2AX-positive cell were observed only in UVB exposed animals at both time intervals. The level of activated caspase-3 and phospho-p53 was increased 24 h after UVA and UVB radiation and was more apparent in UVB treated mice. The results indicate that the mechanism of DNA damage caused by acute UVA exposure includes formation of SSB (oxidative damage), but not double-strand breaks.

• MeSH
• apoptóza účinky záření   MeSH
• DNA účinky záření   MeSH
• fragmentace DNA MeSH
• histony účinky záření   MeSH
• jednořetězcové zlomy DNA MeSH
• kaspasa 3 účinky záření   MeSH
• kůže účinky záření   MeSH
• myši bezsrsté MeSH
• myši MeSH
• nádorový supresorový protein p53 účinky záření   MeSH
• náhodné rozdělení MeSH
• poškození DNA MeSH
• sluneční záření škodlivé účinky   MeSH
• ultrafialové záření škodlivé účinky   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The ultraviolet (UV) region of solar radiation is a critical factor in the initiation and development of a number of skin diseases. However, it is not only skin which is directly exposed to solar light that is affected by UV radiation, through low molecular weight mediators, generated upon irradiation, "non-skin" tissues can also be affected. The aim of this study was to examine in detail, the acute effects of UVA and UVB wavebands on hairless mice. Female SKH-1 hairless mice were exposed to a single dose of UVB (200, 800 mJ/cm(2)) or UVA (10, 20 J/cm(2)) using a solar simulator. The effects on haematological parameters, activity and/or expression of antioxidant enzymes, level of glutathione (GSH), markers of oxidative damage (lipid peroxidation and carbonylated proteins) were analysed in erythrocytes, plasma, liver and whole skin homogenates. No macroscopic changes were observed either 4 or 24 h after UVA/UVB exposure. The blood count showed a significant increase in leukocyte number and reduction of platelets 4 h following UVA and UVB irradiation, which disappeared 24 h after irradiation except for the higher UVA dose. Changes in oxidative stress-related parameters, particularly activity of catalase (CAT) and superoxide dismutase (SOD) and level of GSH and lipid peroxidation products, were found in skin, erythrocytes and liver. The expression of several enzymes (CAT, SOD, glutathione transferase (GST), nicotinamide adenine dinucleotide (phosphate) quinone oxidoreductase (NQO1) and hem oxygenase-1 (HO-1)) in skin was affected following UVA and UVB radiation. Increase in carbonylated proteins was found in plasma and skin samples.

• MeSH
• antioxidancia metabolismus   MeSH
• biologické markery metabolismus   MeSH
• erytrocyty metabolismus   účinky záření   MeSH
• játra enzymologie   účinky záření   MeSH
• karbonylace proteinů účinky záření   MeSH
• krev imunologie   metabolismus   účinky záření   MeSH
• kůže enzymologie   účinky záření   MeSH
• leukocyty účinky záření   MeSH
• myši bezsrsté MeSH
• myši MeSH
• oxidační stres účinky záření   MeSH
• peroxidace lipidů účinky záření   MeSH
• sluneční záření škodlivé účinky   MeSH
• trombocyty metabolismus   účinky záření   MeSH
• ultrafialové záření škodlivé účinky   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH