PHOTOBIOLOGY OF THE LENS

描述(研究人员摘要)：近紫外线来自 众所周知，阳光会增加人类大脑皮层形成的风险 白内障。不同波长近紫外光的作用机理 目前，晶状体上的辐射尚不清楚。这项研究的重点是 量化特定波长的生物有效性 辐射范围在297到400纳米之间的镜片和镜片成分。行动 UVB中单色波长对透镜混浊的影响 (297-320 nm)和UVA(320-400 nm)的生物测定 有意义的条件。完整的牛和人类晶状体和匀浆将 被利用。光谱技术和蛋白质交联将被用于 评估损失。关于特异体生成的定量研究 将进行活性氧物种的检测，以评估它们在光损伤中的作用。 在不同的波长。不到10%的UVB和60%的 UVA可在体内到达人类晶状体上皮细胞。然而，UVB而不是UVA 增加了新近人类皮质性白内障形成的风险 流行病学研究。长波紫外线和长波紫外线辐射对小鼠的生物学效应 晶状体上皮细胞目前尚不清楚。定量作用谱 细胞存活、新合成蛋白质合成和细胞周期调控的研究 这项研究计划对晶状体上皮细胞进行DNA损伤。这些数据 将提供有关近紫外线生物效应的定量信息 上皮细胞上的波长。不同年龄的正常人晶状体 (婴幼儿、青年和老年人)和白内障晶状体上皮细胞 研究确定近紫外线辐射的作用机理 活体的人类晶状体。这项建议的长期目标是 定义晶状体成分变化的分子机制和 更好地理解光损伤和人类 白内障形成。

DESCRIPTION (Investigator's Abstract): Near-ultraviolet light from sunlight is known to increase the risk of formation of human cortical cataracts. The mechanism of action of different wavelengths of near-UV radiation on the lens is unknown at present. The focus of this study is to quantitate the biological effectiveness of specific wavelengths of radiation between 297 and 400 nm on the lens and lens constituents. Action spectra for lens opacification by monochromatic wavelengths in UVB (297-320nm) and UVA (320-400 nm) will be determined under biologically meaningful conditions. Intact bovine and human lenses and homogenates will be used. Spectroscopic techniques and protein crosslinking will be used to assess the damage. Quantitative studies on the generation of specific reactive oxygen species will be done, to assess their role in photodamage at different wavelengths. Less than ten percent of UVB and 60 percent of UVA reaches the human lens epithelium in vivo. However, UVB and not UVA increased the risk of cortical cataract formation in a recent human epidemiological study. The biological effects of UVB and UVA radiation on lens epithelial cells are unknown at present. Quantitative action spectrum studies on the cell survival, synthesis of newly synthesized proteins and DNA damage in lens epithelial cells are planned in this study. These data will provide quantitative information on the biological effects of near-UV wavelengths on the epithelium. Normal human lenses of different ages (infant, young and old), and cataractous lens epithelia will be investigated to determine the mechanism of action of near-UV radiation of the human lens in vivo. The long-term objective of this proposal is to define a molecular mechanism for the changes in lens constituents and obtain a better understanding of the link between photodamage and human cataract formation.