摘要目的 研究脂质过氧化代谢产物4-羟基壬烯醛(HNE)在糖尿病性白内障中的代谢过程以及发病中的作用.方法 实验研究.采用两因素析因设计:处理因素为两水平(正常对照组和糖尿病组),时间因素为三水平(30、45、70 d).对于不同时期的正常与糖尿病大鼠晶状体采用下列方法进行处理:(1)使用一定晕的带有放射活性的HNE与这些晶状体一起培养,测定HNE在晶状体的代谢;(2)分光光度计法测定醛脱氢酶(ALDH)活性;(3)免疫印迹法检测ALDH和HNE-蛋白质加合物的表达.采用两因素析因设计定量资料方差分析对资料进行统计学处理.结果 HNE在正常对照组的晶状体的代谢主要是与谷胱甘肽(GSH)结合形成GS-HNE(约45%),其次为经ALDH氧化成HNA(约9.1%);但糖尿病组晶状体的HNE与GSH结合径路受到抑制,GS-HNE形成减少,与正常组相比30 d时减少约64%(F=49.59,P＜0.001);而糖尿病组晶状体的ALDH氧化径路代偿增强,HNA形成增多,70 d比30 d增多约1.7倍(F=11.51,P=0.0442).糖尿病组的晶状体ALDH活性增高,免疫印迹法显示ALDH较正常对照组增多,HNE-蛋白质加合物较对照组减少.结论糖尿病性白内障中HNE与GSH的结合径路受到抑制,而氧化径路代偿性增强,揭示了结合径路的损伤可能与白内障发生有密切关系,氧化径路的代偿增强可能对防止糖尿病性白内障的发生有一定的意义.(中华眼科杂志,2009,45:248-253)

abstractsObjective To study the metabolism of 4-hydroxynonenal(HNE),one of lipid derived aldehydes(LDAs),in diabetic rat lens and its role in diabetic cataract formation.Methods Experimental research.A factor design was used to set up the experiment statistically upon two factors:diabetic and normal ontrol as treatment factors;day 30,45 and 70 as the time factors.Normal and diabetic rats'lenses were incubated with HNE for 2 hours.HNE metabolites in the culture media were studied by high performance liquid chromatography(HPLC).Aldehyde dehydrogenase(ALDH)activity in normal and diabetic rat lens(30,45 and 70 d after inducing of cataract)was detected by a spectrophotometer,ALDH protein and HNE protein were detected by Western Blot.All data were analyzed by the Bonferroni test using SAS 8.0 software.Results The major pathway for HNE metabolism in normal lens was conjugation with glutathione (GSH)to form GS-HNE(45%),followed by HNE's oxidation to 4-hydroxy-2-nonenoic acid(HNA)by ALDH,which accounted for approximately 9.1% of HNE.The conjugation of HNE with GSH in diabetic lens was decreased approximately 64% at day 30 compared with the controls(F=49.59,P＜0.001).The pathway of HNE oxidation by ALDH in the diabetic lens was enhanced approximately 1.7 times at day 70 compared to day 30(F=11.51,P=0.0442).A higher ALDH activity,greater amount of ALDH protein,and less amount of HNE-protein adduct were presented in diabetic rat lens.Conclusions The pathway of conjugation of HNE with GSH is inhibited in diabetic lens which may play a role in the formation of diabetic cataract.The oxidation of HNE by ALDH is a compensation process for protecting the lens against diabetic damage.(Chin J Ophthalmol,2009,45:248-253)