Development of a method for early diagnosis of diabetic of complications by detecting glycation reaction intermediates.

糖化作用在正常衰老过程中发生，在糖尿病患者中以加速的速度发生，并参与蛋白质和其他细胞成分的结构和功能变化。在糖尿病并发症方面，糖基化假说和Poiyol途径假说通常是独立讨论的。用果糖赖氨酸偶联卵白蛋白免疫兔，制备了一种抗果糖赖氨酸蛋白的抗体。亲和纯化的抗体能识别与果糖孵育的蛋白质，但不能识别与葡萄糖孵育的蛋白质。当牛血清白蛋白与不同浓度的果糖孵育时，抗体的反应性呈剂量和时间依赖性增加。用该抗体对正常或链脲佐菌素诱导的糖尿病大鼠眼部的可溶性蛋白进行酶联免疫吸附试验分析时，发现反应组分随年龄的增长而增加，在糖尿病的情况下也是如此。免疫印迹分析表明晶状体蛋白与该抗体具有较高的反应性。由于果糖主要是通过多元醇途径生物合成的，而多元醇途径在糖尿病条件下会增强，而且已知晶状体具有此途径的高活性，这种抗体能够识别活体中的果糖蛋白。因此，该抗体是一种潜在的有用的工具，用于研究与糖尿病并发症有关的两个主要问题，即糖基化反应和多元醇途径。

Glycation occurs during normal aging and at accelerated rates in diabetes and is involved in structural and functional alterations of proteins and other cellular components. In terms of diabetic complications, the glycation hypothesis and the poiyol pathway hypothesis are usually discussed independently. An antibody was raised against fructated lysine in proteins by immunizing fructated lysine-conjugated ovalbumin in rabbits. The affinity purified antibody specifically recognized proteins incubated with fructose, but not with glucose. When bovine serum albumin was incubated with various concentrations of fructose, the reactivity of thee antibody increased in a dose- and time-dependent manner. When soluble proteins prepared from either normal or streptozotocin-induced diabetic rat eyes were analyzed by ELISA using this antibody, an increase in the reactive components was observed as a function of aging as well as under diabetic conditions. Immunoblot analysis showed that lens crystallin reacted highly with this antibody. Since fructose is largely biosynthesized through the polyol pathway, which is enhanced under diabetic conditions and lens is known to have a high activity of this pathway, this antibody is capable of recognizing fructated proteins in viva. Thus this antibody represents a potentially useful tool for investigating two major issues which appear to be involved in diabetic complications, namely, the glycation reaction and the polyol pathway.