Premium
Effect of natural antioxidants, superoxide dismutase and hydrogen peroxide on capacitation of frozen‐thawed bull spermatozoa
Author(s) -
O'Flaherty C.,
Beconi M.,
Beorlegui N.
Publication year - 2009
Publication title -
andrologia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.633
H-Index - 59
eISSN - 1439-0272
pISSN - 0303-4569
DOI - 10.1111/j.1439-0272.1997.tb00481.x
Subject(s) - capacitation , sperm , lipid peroxidation , chemistry , vitamin e , superoxide dismutase , andrology , thiobarbituric acid , semen , biochemistry , reactive oxygen species , antioxidant , medicine
Summary Bovine spermatozoa from frozenthawed semen are sensitive to lipid peroxidation. Vitamin E protects sperm membrane against oxidative damage. Sperm capacitation produces structural changes on the plasma membrane. Reactive oxygen species could be involved in the capacitation process. The aim of this work was to study the influence of natural antioxidants on the plasma membrane and the influence of reactive oxygen species during bovine sperm capacitation. Sperm samples were frozen in a standard diluent, with and without vitamin E (1 mg ml ‐1 ). Heparin (60 μg ml ‐1 ) was used as a sperm capacitation inductor. Sperm capacitation was evaluated by chlorotetracycline assay. Lipid peroxidation was determined by the 2‐thiobarbituric acid assay. A diminution of thiobarbituric acid reactive substances was observed in sperm samples frozen with vitamin E ( P < 0.05). The addition of vitamin E to the freezing diluent had no effect on the capacitated pattern ( P > 0.05). When vitamin E and vitamin E + vitamin C were added to the capacitation medium, a significant decrease in the percentage of capacitated spermatozoa ( P < 0.05) was observed in both cases. The addition of superoxide dismutase (0.1 mg ml ‐1 ) or H 2 O 2 (50 μM) in the incubation medium, decreased the percentage of capacitated spermatozoa ( P < 0.05). Vitamin E protects the plasma membrane against lipid peroxidation during sperm capacitation, and the presence of superoxide anion would be necessary for frozen‐thawed bull sperm capacitation.