Seven Arzu, Guzel Sava, Seymen Oktay, Civelek Sabiha, Bolayirli Murat, Uncu Murat, Burcak Gulden
Department of Biochemistry, Istanbul University Cerrahpaa Medical Faculty, Turkey.
Yonsei Med J. 2004 Aug 31;45(4):703-10. doi: 10.3349/ymj.2004.45.4.703.
This experimental study was designed to investigate the effects of vitamin E supplementation, especially on lipid peroxidation and antioxidant status elements 3/4 namely, glutathione (GSH), CuZn superoxide dismutase (CuZn SOD), and glutathione peroxidase (GSH Px), both in blood and liver tissues of streptozotocin (STZ) diabetic rats. The extent to which blood can be used to reflect the oxidative stress of the liver is also investigated. In diabetic rats, plasma lipid peroxide values were not significantly different,from control,whereas erythrocyte CuZn SOD (p < 0.01), GSH Px (p < 0.001) activities and plasma vitamin E levels (p < 0.001), were significantly more elevated than controls. Vitamin E supplementation caused significant decreases of erythrocyte GSH level (p < 0.01) in control rats and of erythrocyte GSH Px activity (p < 0.05) in diabetic rats. Liver findings revealed significantly higher lipid peroxide (p < 0.001) and vitamin E (p < 0.01) levels and lower GSH (p < 0.001), CuZn SOD (p < 0.001) and GSH Px (p < 0.01) levels in diabetic rats. A decreased hepatic lipid peroxide level (p < 0.01) and increased vitamin E/lipid peroxide ratio (p < 0.001) were observed in vitamin E supplemented, diabetic rats. A vitamin E supplementation level which did not cause any increase in the concentration of the vitamin in the liver or blood, was sufficient to lower lipid peroxidation in the liver. Vitamin E/lipid peroxide ratio is suggested as an appropriate index to evaluate the efficiency of vitamin E activity,independent of tissue lipid values. Further, the antioxidant components GSH, GSH Px and CuZn SOD and the relationships among them, were affected differently in the liver and blood by diabetes or vitamin E supplementation.
本实验研究旨在探讨补充维生素E的效果，尤其是对链脲佐菌素（STZ）诱导的糖尿病大鼠血液和肝脏组织中脂质过氧化以及抗氧化状态指标3/4，即谷胱甘肽（GSH）、铜锌超氧化物歧化酶（CuZn SOD）和谷胱甘肽过氧化物酶（GSH Px）的影响。同时还研究了血液反映肝脏氧化应激的程度。在糖尿病大鼠中，血浆脂质过氧化物值与对照组无显著差异，而红细胞CuZn SOD（p < 0.01）、GSH Px（p < 0.001）活性以及血浆维生素E水平（p < 0.001）均显著高于对照组。补充维生素E导致对照组大鼠红细胞GSH水平显著降低（p < 0.01），糖尿病大鼠红细胞GSH Px活性显著降低（p < 0.05）。肝脏研究结果显示，糖尿病大鼠肝脏中脂质过氧化物（p < 0.001）和维生素E（p < 0.01）水平显著升高，而GSH（p < 0.001）、CuZn SOD（p < 0.001）和GSH Px（p < 0.01）水平降低。在补充维生素E的糖尿病大鼠中，观察到肝脏脂质过氧化物水平降低（p < 0.01），维生素E/脂质过氧化物比值升高（p < 0.001）。一个不会导致肝脏或血液中维生素浓度升高的维生素E补充水平，足以降低肝脏中的脂质过氧化。维生素E/脂质过氧化物比值被建议作为评估维生素E活性效率的合适指标，与组织脂质值无关。此外，抗氧化成分GSH、GSH Px和CuZn SOD及其相互关系，在肝脏和血液中受糖尿病或维生素E补充的影响不同。
