Rush James W E, Sandiford Shelley D
Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Clin Biochem. 2003 Jul;36(5):345-51. doi: 10.1016/s0009-9120(03)00039-0.
Oxidative stress is implicated in the pathophysiology of many cardiovascular diseases. Plasma glutathione peroxidase (pl x GPx, GPx3) is an antioxidant enzyme found in the extracellular fluid. This study aimed to determine reference values for serum GPx3 concentration and GPx activity in young healthy males and females of similar aerobic fitness and to determine the impact of acute physical activity on serum GPx.
52 young, healthy but not physically trained subjects (24 male, 28 female; age = 20.4 +/- 0.7 yr, cycling VO(2 max) = 39.2 +/- 1.6 mL/kg/min; mean +/- SE) participated in this study. An independent group of 18 subjects participated in an acute, 90 min bout of 50% VO(2 max) cycling exercise. Serum GPx activity and GPx3 protein levels, as well as estradiol and 8-iso- prostaglandin F(2alpha) (8-iso-PGF(2alpha;) an index of lipid peroxidation) were determined.
Females had significantly higher serum GPx3 concentration (29.1 +/- 1.6 vs. 24.2 +/- 1.3 mg/L, p < 0.01) and serum GPx activity (256.4 +/- 10.4 vs. 222.8 +/- 15.6 U/L, p < 0.05) than males; specific activity (U/mg) was not different between genders. There was no significant gender difference in 8-iso-PGF(2alpha). No significant correlation was found between either GPx activity or GPx3 concentration and serum estradiol or VO(2)(max). The acute, prolonged, mild intensity exercise did not affect serum GPx activity or 8-iso-PGF(2a) levels in males or females.
The results of this study suggest that in a young, healthy but not physically well-trained population females are endowed with slightly higher serum GPx3 concentrations and GPx activities than males, but the functional significance of this has not been established. Furthermore, the results indicate that serum GPx levels are not associated with aerobic fitness level, or serum estradiol concentration and that acute, prolonged, mild exercise does not affect the activity of serum GPx in this population.
氧化应激与多种心血管疾病的病理生理学相关。血浆谷胱甘肽过氧化物酶（pl x GPx，GPx3）是一种存在于细胞外液中的抗氧化酶。本研究旨在确定有氧适能相似的年轻健康男性和女性血清GPx3浓度及GPx活性的参考值，并确定急性体力活动对血清GPx的影响。
52名年轻、健康但未经体育训练的受试者（24名男性，28名女性；年龄 = 20.4 ± 0.7岁，骑车最大摄氧量[VO₂max] = 39.2 ± 1.6 mL/kg/min；均值 ± 标准误）参与了本研究。一组18名受试者参加了一次持续90分钟、强度为50%VO₂max的骑车急性运动。测定了血清GPx活性、GPx3蛋白水平，以及雌二醇和8-异前列腺素F₂α（8-iso-PGF₂α；脂质过氧化指标）。
女性的血清GPx3浓度（29.1 ± 1.6 vs. 24.2 ± 1.3 mg/L，p < 0.01）和血清GPx活性（256.4 ± 10.4 vs. 222.8 ± 15.6 U/L，p < 0.05）显著高于男性；比活性（U/mg）在性别间无差异。8-iso-PGF₂α在性别间无显著差异。未发现GPx活性或GPx3浓度与血清雌二醇或VO₂max之间存在显著相关性。急性、长时间、轻度强度运动未影响男性或女性的血清GPx活性或8-iso-PGF₂α水平。
本研究结果表明，在年轻、健康但未经良好体育训练的人群中，女性的血清GPx3浓度和GPx活性略高于男性，但其功能意义尚未明确。此外，结果表明血清GPx水平与有氧适能水平或血清雌二醇浓度无关，且急性、长时间、轻度运动不影响该人群血清GPx的活性。
