活性氧引起的人类精子DNA链断裂

Exogenous hydrogen peroxide and endogenous superoxide anion-induced DNA strand breakage in human spermatozoa

为探讨活性氧对人类精子DNA的损伤作用 ,分别用 0、0 .0 6 2 5、0 .12 5、0 .2 5、0 .5及 1.0mM的H2 O2 和0、0 .1、1.0、2 .0、5 .0mM的 β NADPH在体外条件下处理精子 ,用单细胞凝胶电泳试验检测外源性H2 O2 和内源性O·-2 引起的精子细胞DNA链断裂。结果显示 :用 1.0mMH2 O2 或 5 .0mMNADPH处理精子 30min至 4h ,彗星细胞百分率显著增加 ,平均彗尾也显著增长 ,并有明显的作用时间 效应关系。精子细胞用 0 .0 6 2 5mM～ 1.0mMH2 O2 或 0 .1～ 5 .0mMNADPH处理 1h ,彗星细胞百分率与对照组比较显著增加 ,平均彗尾显著增长 ,并有明显的剂量 效应关系。这些研究结果表明 :外源性H2 O2 和β NADPH在体外条件下刺激精了细胞产生的内源性O·-2

To explore exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa,sperm cells were exposed to different con entrations of H 2O 2 (0,0.062 5,0.125,0.25,0.5 and 1.0 mM) or β?NADPH(0,0.1,1.0,2.0 and 5.0 mM) for 0,30,60,120 and 240 min.The in vitro exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa was detected using single cell gel electrophoresis.The percentage of comet cells was counted and comet tail length was measured.The results showed that comet tail length and comet cell percentage increased in a dose dependent manner in sperm cells treated with 0,0.062 5,0.125,0.25,0.5 and 1.0 mM of H 2O 2 or 0.1,1.0,2.0 and 5.0 mM of β?NADPH at 37℃ for 1 h.When sperm cells were incubated with 1.0 mM of H 2O 2 or 5.0 mM of β?NADPH for 30,60,120 and 240 min,comet tail length and comet cell percentage increased in a time dependent manner.This study indicated that both exogenous hydrogen peroxide and endogenous superoxide anion can induce DNA strand breakage in human spermatozoa.