SCAVENGING EFFECT OF N-ACETYL-L-CYSTEINE AGAINST REACTIVE OXYGEN SPECIES IN HUMAN SEMEN - A POSSIBLE THERAPEUTIC MODALITY FOR MALE FACTOR INFERTILITY

A new approach to reduce the level of reactive oxygen species (ROS) in human semen by using N-acetyl-L-cysteine (NAC) was evaluated. Semen s amples were incubated with or without NAC (1.0 mg ml(-1)) at room temp erature. The chemiluminescent signal of the oxidation of luminol was d etected by means of an MTP reader after 0, 20, 40, 60 and 120 min, res pectively, using 200 mu M luminol. In addition, the dose-dependent act ion of NAC (0.1, 1.0 and 5.0 mg ml(-1)) and the influence of NAC on fu nctional sperm parameters (motility and acrosome reaction) were studie d. ROS levels decreased significantly after 20 min incubation with NAG . This reduction was greater in the high ROS group (> 30 000 counts/10 (7) viable sperm at t = 0) than in the low ROS group (< 30 000). In ad dition, a marked dose-dependence of NAC was observed. Concerning sperm function, total sperm motility improved after incubation with NAC, bu t no significant change was observed with respect to the acrosome reac tion. NAC (at concentrations of 1.0 mg ml(-1)) significantly reduced R OS in human semen and showed the possibility of improving impaired spe rm function. After further testing NAC might be useful for the treatme nt of male infertility patients.