Effects of Anti-oxidants in Freezing and Thawing of Sperm

Lee, Young Jin; Park, Nam Cheol

Abstract

PURPOSE: It is known that reactive oxygen species which increase during the cryopreservation of sperm are harmful to sperm. This study analyzed the concentration, motility, morphology and lipid peroxidation of cell membrane before and after the cryopreservation of sperm for an evaluation of the influences of reactive oxygen species in sperm function.
MATERIALS AND METHODS
Semen samples from 50 normal healthy volunteers were collected by masturbation. After liquefaction at room temperature, the semen was divided and stored in cryogenic tubes supplemented with Ham`s F-10 medium and a cryoprotective agent. To the experimental group was added superoxide dismutase(SOD, Sigma, USA) 100microliter, catalase (Sigma, USA) 100microliter, SOD and catalase 50microliter and 200microliter, glutathione peroxidase 10microliter, SOD and glutathione peroxidase 50microliterand 20microliter. It was then divided into groups I, II, III, IV and V. Antioxidant was not added to the control group. All specimens were cryopreservated at -196degrees C liquid nitrogen, then thawed at room temperature. We analyzed sperm motility and morphology, and the level of lipid peroxidation was measured by thiobarbituric acid(TBA).
RESULTS
The sperm concentration and morphology did not show any significant differences statistically between the experimental and the control groups. After cryopreservation, the sperm motility was significantly decreased in the experimental and the control groups(p<0.05). In groups II, III, IV and V, the sperm motility decreased more than in group I and the control group(p<0.05). In groups II, III, IV and V, lipid peroxidation of cell membrane was significantly lower than in group I and the control group(p<0.05). In both the experimental and the control groups, the ratio of motile sperm decreased significantly, according to increasing lipid peroxidation(p<0.05, r=0.566).
CONCLUSIONS
We conclude from this study that the reactive oxygen species occuring in sperm cryopreservation may significantly influence the function of sperm. A cryoprotective agent supplemented with proper anti-oxidant may reduce the harmful effect associated with sperm cryopreservation.