title: Alpha-tocopherol improves biochemical and dynamic parameters in cryopreserved boar semen.
abstract: Cryopreservation is associated with the production of reactive oxygen species which lead to lipid peroxidation of sperm membranes. The objective was to determine an alpha-tocopherol concentration capable of improving the quality of cryopreserved porcine semen. Boar spermatozoa frozen with 200, 500 or 1000 microg/mL alpha-tocopherol were thawed and incubated at 37 degrees C for 4 h. Routine parameters of semen quality, susceptibility to lipid peroxidation 2-thiobarbituric acid (TBARS) and oxygen uptake were evaluated. Motility was higher (P<0.05) in samples treated with different concentrations of alpha-tocopherol up to 2 h of incubation. Viability and acrosome integrity significantly decreased during incubation (no significant differences between treatments). Two hundred micrograms per milliliter alpha-tocopherol protected spermatozoa against lipid peroxidation during incubation, but 1000 microg/mL failed to protect after 2 h of incubation. There was a negative association between TBARS and motility, suggesting that lipid peroxidation affected sperm motility. Both control and 200 microg/mL alpha-tocopherol samples preserved the capacity to generate oxidative energy up to 1 h of incubation. The addition of 200 microg/mL alpha-tocopherol in the semen extender could be useful to preserve boar spermatozoa against the oxidative stress generated by cryopreservation.
authors.affiliation: Area of Biochemistry, School of Veterinary Sciences, University of Buenos Aires, Chorroarín 280, C1427CWO Buenos Aires, Argentina. ebreininger@fvet.uba.ar
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Breininger
authors.forename: Norma B
authors.initials: NB
authors.lastname: Beorlegui
authors.forename: Cristián M
authors.initials: CM
authors.lastname: O'Flaherty
authors.forename: Martha T
authors.initials: MT
authors.lastname: Beconi
mesh_terms: D000177:Acrosome / Q000502:physiology; D000818:Animals; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D004305:Dose-Response Relationship, Drug; D015227:Lipid Peroxidation; D008297:Male; D010101:Oxygen Consumption; D012661:Semen / Q000737:chemistry; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013076:Sperm Count; D013081:Sperm Motility; D013552:Swine; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D024502:alpha-Tocopherol / Q000008:administration & dosage*
chemical_list: D017392:Thiobarbituric Acid Reactive Substances; D024502:alpha-Tocopherol