RELATIONSHIP OF SPERM SUPEROXIDE DISMUTASE-LIKE ACTIVITY WITH OTHER SPERM-SPECIFIC ENZYMES AND EXPERIMENTALLY-INDUCED PEROXIDATION IN INFERTILE MEN

Superoxide dismutase-like activity (SOD-like), isoenzyme lactate dehyd rogenase-C4 (LDH-C4) and NADH-diaphorase activities in spermatozoa hav e been investigated from 58 normozoospermic and 27 oligozoospermic men . Significantly higher SOD-like, LDH-C4 and diaphorase activities (P<0 .01, P<0.005 and P<0.0001, respectively) were detected in spermatozoa from oligozoospermic men, compared to the activities found in normozoo spermic samples. SOD-like activity (mean +/- SE) in oligozoospermic sa mples amounted to 8.3 +/- 1.6 U 10(-8) spermatozoa, while in spermatoz oa in normozoospermic men with a sperm concentration above 20 million of spermatozoa per mi amounted to 4.2 +/- 0.5 U 10(-8). There was a cl ose correlation between the SOD-like activity and biochemical indicato rs of the presence of residual cytoplasm i.e. isoenzyme LDH-C4 and NAD H-diaphorase (r=0.53 and r=0.66 in normozoospermic and r=0.63 and r=0. 54 in oligozoospermic men, respectively). A positive relationship betw een SOD-like activity and experimentally-induced lipid peroxidation wa s detected in 54 infertile men (r=0.30; P<0.05). These findings sugges t that a higher level of superoxide dismutase-like activity may reflec t a defect in the development or maturation of spermatozoa and, thereb y, a decreased fertility potential. Hence, determination of SOD-like a ctivity may give information on the state of maturity of human spermat ozoa, while its role in the antioxidative protection remains to be det ermined.