丙酮酸对大鼠糖尿病性白内障抑制作用的实验研究

Effects of pyruvate on the experimentally induced diabetic cataract in rats

目的探讨丙酮酸对大鼠糖尿病性白内障的抑制作用。方法Wister大鼠120只,随机分为对照组、模型组及治疗组三组。模型组、治疗组应用链脲佐菌(STZ)诱发糖尿病。治疗组饲料及饮水中添加2%丙酮酸钠。在实验第4、8、12周观察晶状体透明度的变化并在实验第12周观察三组大鼠晶状体组织中葡萄糖、山梨醇、果糖以及GSH、MDA、ATP的变化。结果治疗组晶状体较模型组混浊程度明显减轻,晶状体中葡萄糖、山梨醇含量均明显下降,果糖无明显变化。MAD下降,GSH及ATP水平升高。结论丙酮酸可抑制高糖引起的多元醇代谢通路的激活,减轻氧化应激反应,改善晶状体的能量代谢,抑制糖尿病性白内障的发生。

Objective To investigate the inhibition by pyruvate on cataract in diabetic rats. Methods 120 Wister rats were randomly divided into 3 groups of 40 rats：control group,model group and pyruvate group. Diabetes was induced by the intraabdominally injection of 0. 1% streptozotocin（STZ） in model and pyruvate groups,and the pyruvate group received 2% pyruvate in the diet and drinking water. At the end of experiment, the level of glucose, sorbitol, fructose, GSH （glutathione） , MDA （malondialdehyde） ,ATP in the lens were determined. The opacification of lens was detected by microscope. Results The contents of sotbitol,glucose, fructose（ 30.21± 3.10,17.54±2.42 and 11.46±1.59μmol/g respectively ） and MDA （23.11±1.46 nmol/g） were increased and those of GSH ,ATP（2.07±0. 23μmol/g and 544.87±11.45 nmol/g） were decreased in model group compared with control group（ 3.07±0. 34,3.26±0. 42,1.59±0. 61 μ mol/g and 11.63±1.22 nmol/g, 9. 43±0. 97μmol/g,2 327.71±134.03 nmol/g, respectively,P 〈 0. 01 ） , and the administration of pyruvate decreased the levels of sotbitol, glucose,lipid peroxidation （ MDA ） （ 7.52±0.69,6. 34±0.92,10. 62±0. 73 μmol/g and 17.23±0. 90 nmol/g） and increased the levels of GSH and ATP（5.98±0. 36μmol/g and 1 660. 53±69.54 nmol/g） in comparison with model group（P 〈0. 05 ,P 〈 0. 01 ）. There was no statistical difference in fructose content in lens between model group and pyruvate group（ P 〉 0.05 ）. The progress of cataract was also significantly delayed. Conclusion Administration of pyruvate by oral route can effectively inhibit diabetic cataractogenesis in rats through inhibiting polyol pathway, reducing oxidative damage and improving energy metabolism.