Molecular Analysis of Microdissected Cataractous Human Lenses

显微解剖白内障人类晶状体的分子分析

• 批准号: 7159319
• 负责人: Marc Kantorow
• 金额: $ 30.38万
• 依托单位: FLORIDA ATLANTIC UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-30 至 2009-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7159319
• 关键词: Age; Aging; Binding; Cataract; Cells; Crystallins; Development; Disease; Electron Microscopy; Enzymes; Epithelium; Gene Targeting; Gene Transfer; Genes; Human; Hyperbaric Oxygen; Immunohistochemistry; In Vitro; Lens Opacities; Link; Longevity; Measurement; Membrane; Methionine; Molecular Analysis; Monitor; Mus; Nuclear; Oxidative Stress; Pattern; Play; Predisposition; Proteins; Range; Relative (related person); Research Personnel; Reverse Transcriptase Polymerase Chain Reaction; Role; Small Interfering RNA; Sulfoxide; System; Testing; Time; Transcript; Wild Type Mouse; Work; Yeasts; age related; enzyme activity; in vivo; lens; lens protein; light scattering; methionine sulfoxide; methionine sulfoxide reductase; oxidation; programs; repaired; sulfoxide reductase

DESCRIPTION (provided by applicant): Methionine sulfoxide reductases are unique in their ability to actually repair oxidative stress damage through the direct reduction of oxidized methionine residues and are likely to play key roles in lens aging and cataract formation. MsrA activity has been detected in the human lens, and the oxidized methionine content of human lens proteins increases with age reaching levels as high as 60% in age-related cataract relative to clear human lenses. This proposal will test the hypothesis that methionine sulfoxide reductases defend the lens against oxidative stress damage and that decreased Msr levels and/or activities are associated with increased oxidation of lens methionines, lens damage and cataract. To test this hypothesis: (1) The identities, levels, activities and sub-cellular localization patterns of methionine sulfoxide reductases of the human and mouse lens will be established; (2) The ability of methionine sulfoxide reductases to defend the lens against oxidative-stress will be determined; and (3) the relationship between methionine sulfoxide reductase activity and methionine oxidation will be established in lens aging and age-related cataract. These aims will be accomplished using an integrative approach that functionally tests the in vitro and in vivo ability of methionine sulfoxide reductases to defend the lens against oxidative stress damage and directly examines methionine sulfoxide reductase activities in actual human lenses and cataracts. The feasibility of this work is supported by the initial identification and spatial characterization of three separate methionine sulfoxide reductase genes in the human lens and the demonstration that at least one of these genes, called MsrA, can directly defend lens cells against oxidative stress damage.

描述（由申请人提供）：甲硫氨酸亚砜还原酶具有独特的能力，能够通过直接还原氧化的甲硫氨酸残基来实际修复氧化应激损伤，并且可能在晶状体老化和白内障形成中发挥关键作用。在人类晶状体中检测到了 MsrA 活性，并且人类晶状体蛋白的氧化蛋氨酸含量随着年龄的增长而增加，相对于透明的人类晶状体，在与年龄相关的白内障中达到高达 60% 的水平。该提案将检验以下假设：蛋氨酸亚砜还原酶可保护晶状体免受氧化应激损伤，并且 Msr 水平和/或活性降低与晶状体蛋氨酸氧化增加、晶状体损伤和白内障有关。为了检验这一假设：（1）将建立人和小鼠晶状体的蛋氨酸亚砜还原酶的特性、水平、活性和亚细胞定位模式； (2) 测定蛋氨酸亚砜还原酶保护晶状体免受氧化应激的能力； (3)在晶状体老化和年龄相关性白内障中，将建立蛋氨酸亚砜还原酶活性与蛋氨酸氧化之间的关系。这些目标将使用综合方法来实现，该方法对体外和体内能力进行功能测试 研究人员利用蛋氨酸亚砜还原酶来保护晶状体免受氧化应激损伤，并直接检查实际人类晶状体和白内障中的蛋氨酸亚砜还原酶活性。这项工作的可行性得到了人类晶状体中三个独立甲硫氨酸亚砜还原酶基因的初步鉴定和空间特征的支持，并证明这些基因中至少有一个称为 MsrA，可以直接保护晶状体细胞免受氧化应激损伤。