The objective of this work was to examine the time-dependent pro-oxidant versus antioxidant effect of various doses of vitamin E used commonly in experimental studies. Erythrocyte activity of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and plasma lipid peroxidation levels were investigated following biweekly intramuscular administration of 100, 300 and 600 mg/kg of vitamin E at a baseline time point, and additionally at 2, 4 and 6 weeks after initiating treatment. Vitamin E had an antioxidant effect when administered at low doses over short time periods, and increased the activity of antioxidant enzymes. At higher doses and over longer time periods, it increased the level of lipid peroxidation, and attenuated the activity of antioxidant enzymes. These results suggest that time-dependent variations in vitamin E effects should be considered in design and interpretation of experimental antioxidant studies, as well as during clinical trials.

中文翻译：

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维生素E对大鼠体内脂质过氧化的剂量依赖性调节和抗氧化酶的活性。

这项工作的目的是检验实验研究中常用的各种剂量维生素E的时间依赖性促氧化剂与抗氧化剂作用。在基线时间点每两周肌肉注射100、300和600 mg / kg的维生素E之后，研究了超氧化物歧化酶（SOD），谷胱甘肽过氧化物酶（GPX），过氧化氢酶（CAT）和血浆脂质过氧化水平的红细胞活性，此外在开始治疗后的2、4和6周。维生素E在短时间内低剂量给药时具有抗氧化作用，并增加了抗氧化酶的活性。在更高剂量和更长的时间内，它会增加脂质过氧化的水平，并减弱抗氧化酶的活性。