Hattori-Nakakuki Y, Nishigori C, Okamoto K, Imamura S, Hiai H, Toyokuni S
Department of Pathology, Faculty of Medicine, Kyoto University, Japan.
Biochem Biophys Res Commun. 1994 Jun 30;201(3):1132-9. doi: 10.1006/bbrc.1994.1823.
Six-week-old male albino hairless mice (Hos: Hr-1) were exposed to a near-ultraviolet (UV) fluorescent sun lamp (33.5 kJ/m2/hr; wave length > 270 nm with a peak at 312.5 nm) to investigate the induction of oxidative DNA damage in epidermal cells. Significantly higher levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) were detected in a dose-dependent manner in epidermis of mice exposed to near-UV than in those of control animals. The ratio of 8-OHdG in near-UV-exposed/unexposed control was 2.08 +/- 0.19 after 168 kJ/m2 exposure, P < 0.01; 3.49 +/- 0.36 after 335 kJ/m2 exposure, P < 0.01 (means +/- SE). The levels of 8-OHdG decreased with time after near-UV exposure, suggesting the presence of removal and/or repair mechanisms. This is the first report that oxidative DNA base modification is induced in vivo in epidermal cells by near-UV exposure. Oxidative DNA base modification may be one of the causes of sunlight-induced skin carcinogenesis.
六周龄雄性白化无毛小鼠（品系：Hr-1）暴露于近紫外线（UV）荧光太阳灯下（33.5 kJ/m²/小时；波长>270 nm，峰值在312.5 nm），以研究表皮细胞中氧化性DNA损伤的诱导情况。在暴露于近紫外线的小鼠表皮中，以剂量依赖方式检测到的8-羟基-2'-脱氧鸟苷（8-OHdG）水平显著高于对照动物。暴露于168 kJ/m²后，近紫外线暴露组与未暴露对照组的8-OHdG比值为2.08±0.19，P<0.01；暴露于335 kJ/m²后为3.49±0.36，P<0.01（平均值±标准误）。近紫外线暴露后，8-OHdG水平随时间下降，表明存在清除和/或修复机制。这是首次报道近紫外线暴露可在体内诱导表皮细胞发生氧化性DNA碱基修饰。氧化性DNA碱基修饰可能是阳光诱导皮肤癌发生的原因之一。
