活性氧通过氧化小鼠精子中的巯基蛋白来阻断精卵融合。

Reactive oxygen species block sperm-egg fusion via oxidation of sperm sulfhydryl proteins in mice.

作者信息

Mammoto A, Masumoto N, Tahara M, Ikebuchi Y, Ohmichi M, Tasaka K, Miyake A

机构信息

Department of Obstetrics and Gynecology, Osaka University Medical School, Japan.

出版信息

Biol Reprod. 1996 Nov;55(5):1063-8. doi: 10.1095/biolreprod55.5.1063.

DOI:10.1095/biolreprod55.5.1063

PMID:8902218

Abstract

The effects of reactive oxygen species (ROS) on mouse sperm-egg fusion were determined. Sperm were treated with superoxide and hydrogen peroxide generated by addition of xanthine oxidase (XO: 10-200 mlU/ml) to hypoxanthine (HX: 1 mM). While XO at concentrations higher than 100 mlU/ml decreased the motility and lipid peroxidation of sperm, XO at less than 50 mlU/ml had no such effect. However, 20-50 mlU/ml XO significantly suppressed sperm fusion with zona-free eggs. Two ROS scavengers, superoxide dismutase and catalase, attenuated the inhibition of sperm-egg fusion by HX-XO. The sulfhydryl (SH) reductant, dithiothreitol, also reversed the inhibition. The sperm SH-rich fusion-related proteins were highly sensitive to ROS. These results suggest that ROS at low concentrations may inhibit sperm-egg fusion via oxidation of the SH-proteins in the sperm membrane, without causing loss of motility.

摘要

研究了活性氧（ROS）对小鼠精卵融合的影响。通过向次黄嘌呤（HX：1 mM）中添加黄嘌呤氧化酶（XO：10 - 200 mU/ml）来产生超氧化物和过氧化氢，并用其处理精子。虽然浓度高于100 mU/ml的XO会降低精子的活力和脂质过氧化，但浓度低于50 mU/ml的XO则无此作用。然而，20 - 50 mU/ml的XO能显著抑制精子与去透明带卵的融合。两种ROS清除剂，超氧化物歧化酶和过氧化氢酶，可减弱HX - XO对精卵融合的抑制作用。巯基（SH）还原剂二硫苏糖醇也能逆转这种抑制作用。精子中富含SH的融合相关蛋白对ROS高度敏感。这些结果表明，低浓度的ROS可能通过氧化精子膜中的SH蛋白来抑制精卵融合，而不会导致活力丧失。