IMMUNOCHEMICAL STUDIES OF LENS PIGMENTS

随着年龄的增长，人类晶状体细胞核逐渐变得更黄 白内障形成。这颗原子核的颜色，是由Fast 光谱扫描比色法(FSSC)是一种颜色测量系统 强烈影响对比敏感度功能(CSF)。有能力 颜色参数与视觉功能障碍直接相关是一个主要的 在视觉研究方面的成就。然而，原子核颜色的起源是 仍然没有确定的证据。有三种机制可以产生黄色 体外实验中的色素：光氧化、非酶高级 糖基化和脂质过氧化。据推测，晶状体色素 主要来源于晚期糖基化，因为晶状体生理学有利于 糖基化机制。然而，很难识别和量化 人晶状体中的糖基化色素或其他色素通过生化和 生物物理测量。这是因为色素发色团是 它们对酸水解不敏感，分子光谱相似 特征(紫外可见吸收和蓝色荧光)。免疫化学 测量可能会提供另一种选择。在这项提案中，少校 目标包括：(I)生产和表征颜料 体外高级糖基化、紫外光的光氧化和脂质 过氧化；(2)分离荧光交联物(有色) 多肽)，并将其作为抗原用于制备多克隆和 (3)进行免疫化学检测 (Western blotting和ELISA法)，试图鉴定和量化 白内障手术后晶状体标本中的色素。这将允许我们 明确导致晶状体色泽暗淡的主要色素沉着机制 一种特殊类型的白内障。这方面的知识可能有助于 一种减缓或阻止晶状体褐变的药物方法的开发 并可以为患者提供更多的非手术治疗选择 与白内障和年龄相关的视力丧失。

The human lens nucleus becomes progressively more yellow with age and with cataract formation. This nuclear color, measured accurately by the Fast Spectral Scanning Colorimetry (FSSC), a color measuring system, was found to affect strongly the contrast sensitivity function (CSF). The ability to correlate color parameters directly with visual dysfunction is a major accomplishment in vision research. However, the origin of nuclear color is still not definitely established. Three mechanisms can produce yellow pigments in in vitro experiments: photooxidation, nonenzymatic advanced glycation, and lipid peroxidation. It is hypothesized that lens pigments originate mostly from advanced glycation, since lens physiology favors the glycation mechanism. However, it is difficult to identify and quantify the glycation pigments or other pigments in the human lens by biochemical and biophysical measurements. This is because the pigment chromophores are labile to acid hydrolysis and they have similar molecular spectral features (UV-visible absorption and blue fluorescence). Immunochemical measurement may provide an alternative. In this proposal, the major objectives include: (i) to produce and characterize the pigments by in vitro advanced glycation, photooxidation of UV light, and lipid peroxidation; (2) to isolate fluorescent cross-linked species (pigmented peptides) and to use them as antigens in the preparation of polyclonal and monoclonal antibodies; and (3) to perform immunochemical measurements (Western blotting and ELISA) in an attempt to identify and quantify pigments in lens specimens from cataract surgery. This will permit us to define the predominant pigmentation mechanism that causes lens brunescence in a particular type of cataract. This knowledge may help in the development of a pharmaceutical means of slowing or stopping lens browning and could offer patients additional non-surgical options of treating cataract- and age-related vision loss.