The presence of a human UV filter within the lens represents an oxidative stress.

摘要: It has recently been demonstrated that, with age, UV filters such as 3-hydroxykynurenine glucoside, bind to proteins in the human lens. This covalent interaction leads colouration of normal lens, and results from instability kynurenine side chain. Other primate filters, addition containing same chain, can also be readily oxidized. One compound is (3OHKyn). proposed that oxidation bound and/or free 3OHKyn may give rise lens associated age-related nuclear cataract. Therefore it become important understand within In this study, intact bovine lenses (which lack filters) were incubated various parameters monitored. The effect exposure hyperbaric oxygen (HBO) was assessed, both alone, combination prior incubation. Glutathione (GSH), protein sulfhydryl protein-bound levels, well soluble content gel filtration profiles, obtained for cortical regions after defined periods presence filter, 3OHKyn, at concentrations similar those present shown produce considerable oxidative stress judged by its on GSH. noted under normobaric conditions, but exacerbated increased oxygen. Exposure HBO caused a marked fall GSH regions. exaggerated 3OHKyn. treatment lead content, however, only partial (approximately 1 mol SH per protein) changed slowly, even extended HBO, suggesting most crystallin groups buried. did not appreciably affect although cause an increase level sulfhydryl. produced more than two-fold cortex. There little influence alone solubility, incubation, incubation 72 hr significant insoluble particularly nucleus. insolubilization further FPLC profiles showed proportion gamma beta crystallins fraction decreased following these involved disulfide bond formation. study demonstrates oxidized compound, filter represents processes if concentration increased. We speculate factor account evolution unusually high levels glutathione reductase lenses.