An investigation of the effectiveness of certain antioxidants in preserving the motility of reactivated bull sperm models.
Bull sperm that had been disrupted by freezing and thawing were reactivated with 1 mM Mg-adenosine 5'-triphosphate. The antioxidants superoxide dismutase, catalase, dithiothreitol, and reduced glutathione (GSH) were tested for their ability to prolong the motility of the reactivated sperm. GSH was employed both by itself and as part of a reducing system that maintained the tripeptide in the reduced form. Three of the test agents were found to increase the duration of motility in the sperm preparations; these were reduced glutathione, dithiothreitol, and superoxide dismutase. Glutathione was the most effective protective agent, yielding reactivated preparations with a half-life for the decay of motility of 2.5 h. While dithiothreitol (DTT) is widely employed as an antioxidant, we found that DTT is measurably less effective than glutathione (half-life of 1.5 h). In spite of glutathione's effectiveness in preserving motility, we have found, by direct assay, that mature bull sperm do not contain detectable amounts of this common biological antioxidant. Our results support the hypothesis that oxidative damage contributes to the loss of motility in reactivated sperm and suggest that oxidation could be a factor in motility loss in living sperm.
Lindemann
C B
CB
Department of Biological Sciences, Oakland University, Rochester, Michigan 48063.
O'Brien
J A
JA
Giblin
F J
FJ
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002374:Catalase / Q000494:pharmacology; D002417:Cattle; D004229:Dithiothreitol / Q000494:pharmacology; D005615:Freezing; D005978:Glutathione / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D010084:Oxidation-Reduction; D012662:Semen Preservation; D013081:Sperm Motility / Q000187:drug effects*; D013482:Superoxide Dismutase / Q000494:pharmacology
D000975:Antioxidants; D000255:Adenosine Triphosphate; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione; D004229:Dithiothreitol