title: Combining reduced glutathione and ascorbic acid has supplementary beneficial effects on boar sperm cryotolerance.
abstract: The main aim of this work was to evaluate how supplementing freezing and thawing media with reduced glutathione (GSH) and l-ascorbic acid (AA) affected the quality parameters of frozen-thawed boar spermatozoa. With this purpose, semen samples of 12 ejaculates coming from 12 boars were used. Each ejaculate was split into seven aliquots to which 5 mM of GSH and 100 μM of AA were added separately or together at two different steps of freeze-thawing. Various sperm parameters (levels of free cysteine residues in sperm nucleoproteins, sperm viability, acrosome membrane integrity, intracellular peroxide and superoxide levels [ROS], and total and progressive motility) were evaluated before freezing and at 30 and 240 minutes after thawing. Both GSH and AA significantly improved boar sperm cryotolerance when they were separately added to freezing and thawing media. However, the highest improvement was recorded when both freezing and thawing media were supplemented with 5 mM of GSH plus 100 μM of AA. This improvement was observed in sperm viability and acrosome integrity, sperm motility, and nucleoprotein structure. Although ROS levels were not much increased by freeze-thawing procedures, the addition of GSH and AA to both freezing and thawing extenders significantly decreased intracellular peroxide levels and had no impact on superoxide levels. According to our results, we can conclude that supplementation of freezing and thawing media with both GSH and AA has a combined, beneficial effect on frozen-thawed boar sperm, which is greater than that obtained with the separate addition of either GSH or AA.
authors.affiliation: Unit of Animal Reproduction, Department of Animal Medicine and Surgery, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain; Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Giaretta
authors.affiliation: Unit of Animal Reproduction, Department of Animal Medicine and Surgery, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain.
authors.forename: Efrén
authors.initials: E
authors.lastname: Estrada
authors.affiliation: Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Bucci
authors.affiliation: Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy.
authors.forename: Marcella
authors.initials: M
authors.lastname: Spinaci
authors.affiliation: Unit of Animal Reproduction, Department of Animal Medicine and Surgery, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain.
authors.forename: Joan E
authors.initials: JE
authors.lastname: Rodríguez-Gil
authors.affiliation: Unit of Animal Reproduction, Department of Animal Medicine and Surgery, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain. Electronic address: marc.yeste@uab.cat.
authors.forename: Marc
authors.initials: M
authors.lastname: Yeste
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D005978:Glutathione / Q000494:pharmacology*; D008297:Male; D017382:Reactive Oxygen Species; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013094:Spermatozoa / Q000502:physiology*; D013552:Swine / Q000502:physiology*
chemical_list: D003451:Cryoprotective Agents; D017382:Reactive Oxygen Species; D005978:Glutathione; D001205:Ascorbic Acid
keywords: Ascorbic acid; Boar semen; Reduced glutathione; Sperm cryopreservation; Sperm survival