Chen C S, Chao H T, Pan R L, Wei Y H
Department of Biochemistry, National Yang-Ming University, Taipei, Taiwan.
Biochem Mol Biol Int. 1997 Oct;43(2):291-303. doi: 10.1080/15216549700204071.
We employed the xanthine-xanthine oxidase system to produce H2O2 or simply used commercially available H2O2 solution to investigate the effects of exogenous hydroxyl radicals on the motility characteristics and on lipid peroxidation and DNA modification of human sperm. The functional parameters of sperm motility declined concomitantly upon incubation of sperm with hydroxyl radicals. After incubation of freshly ejaculated human sperm with 0.23 mM H2O2 in the presence of 1.8 mM ADP and 2.7 mM FeSO4 for 1 hr at 37 degrees C, 90% reduction of motility was observed. Effect of hydroxyl radicals on sperm motility was dependent on the concentrations of FeSO4 and H2O2, respectively. The remaining motility of sperm after 1 hr incubation showed negative linear correlation with FeSO4 concentration. The response of sperm motility to FeSO4 was also dependent on the concentration of H2O2. Except for the amplitude of lateral head displacement, functional parameters of sperm declined with the increase of H2O2 concentration. Moreover, we found that lipid peroxidation measured as malondialdehyde (MDA) and accumulation of modified DNA indicated by 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in human sperm were significantly accelerated by exogenous hydroxyl radicals. The contents of lipid peroxides and 8-OH-dG in the spermatozoa were increased from 24.6 +/- 2.4 nmol MDA/1 x 10(7) sperm and 0.17 +/- 0.02% in the untreated group to 30.6 +/- 1.2 nmol MDA/1 x 10(7) sperm and 1.9 +/- 0.47%, respectively, in the sperm treated at 37 degrees C for 1 hr with 2.03 mM H2O2, 1.8 mM ADP and 4.5 mM FeSO4. Taken together, these results suggest that the detrimental effects of hydroxyl radicals on human sperm functions may be mediated, at least partly, through lipid peroxidation and DNA modification.
我们采用黄嘌呤-黄嘌呤氧化酶系统产生过氧化氢（H2O2），或者直接使用市售的H2O2溶液来研究外源性羟基自由基对人类精子运动特性、脂质过氧化和DNA修饰的影响。精子与羟基自由基孵育后，其运动功能参数随之下降。在37℃下，将新鲜射出的人类精子与0.23 mM H2O2在1.8 mM ADP和2.7 mM硫酸亚铁（FeSO4）存在的条件下孵育1小时后，观察到精子活力降低了90%。羟基自由基对精子活力的影响分别取决于FeSO4和H2O2的浓度。孵育1小时后精子的剩余活力与FeSO4浓度呈负线性相关。精子活力对FeSO4的反应也取决于H2O2的浓度。除了头部横向位移幅度外，精子的功能参数随H2O2浓度的增加而下降。此外，我们发现，以丙二醛（MDA）衡量的脂质过氧化以及以8-羟基-2'-脱氧鸟苷（8-OH-dG）表示的修饰DNA的积累在人类精子中被外源性羟基自由基显著加速。在37℃下用2.03 mM H2O2、1.8 mM ADP和4.5 mM FeSO4处理精子1小时后，精子中脂质过氧化物和8-OH-dG的含量分别从未处理组的24.6±2.4 nmol MDA/1×10（7）个精子和0.17±0.02%增加到30.6±1.2 nmol MDA/1×10（7）个精子和1.9±0.47%。综上所述，这些结果表明，羟基自由基对人类精子功能的有害影响可能至少部分是通过脂质过氧化和DNA修饰介导的。
