title: Response of thawed epididymal red deer spermatozoa to increasing concentrations of hydrogen peroxide, and importance of individual male variability.
abstract: Oxidative stress represents a challenge during sperm manipulation. We have tested the effect of increasing hydrogen peroxide (H(2)O(2)) levels on red deer spermatozoa after cryopreservation, and the role of male-to-male variation in that response. In a first experiment, eight thawed samples were submitted to 0, 25, 50, 100 and 200 μm H(2)O(2) for 2 h at 37 °C. Intracellular reactive oxygen species (H(2)DCFDA-CM) increased with H(2)O(2) concentration, but we only detected a decrease in sperm function (motility by CASA and chromatin damage by sperm chromatin structure assay) with 200 μm. Lipoperoxidation assessed by the thiobarbituric acid reactive substance (TBARS) method increased slightly with 50 μm H(2)O(2) and above. In a second experiment, samples from seven males were submitted to 0 and 200 μm H(2)O(2) for 2 h, triplicating the experiment within each male. Males differed at thawing and regarding their response to incubation and H(2)O(2) presence. We found that the kinematic parameters reflected male-to-male variability, whereas the response of the different males was similar for lipid peroxidation and viability. A multiparametric analysis showed that males grouped differently if samples were assessed after thawing, after incubation without H(2)O(2) or after incubation with H(2)O(2) . Red deer spermatozoa are relatively resilient to H(2)O(2) after thawing, but it seems to be a great male-to-male variability regarding the response to oxidative stress. The acknowledgement of this individual variability might improve the development of optimized sperm work protocols.
authors.affiliation: Reproductive Biology Group, National Wildlife Research Institute (IREC), UCLM-CSIC-JCCM, Albacete, Spain.
authors.forename: A E
authors.initials: AE
authors.lastname: Domínguez-Rebolledo
authors.forename: F
authors.initials: F
authors.lastname: Martínez-Pastor
authors.forename: A F
authors.initials: AF
authors.lastname: Bisbal
authors.forename: J L
authors.initials: JL
authors.lastname: Ros-Santaella
authors.forename: O
authors.initials: O
authors.lastname: García-Álvarez
authors.forename: A
authors.initials: A
authors.lastname: Maroto-Morales
authors.forename: A J
authors.initials: AJ
authors.lastname: Soler
authors.forename: J J
authors.initials: JJ
authors.lastname: Garde
authors.forename: M R
authors.initials: MR
authors.lastname: Fernández-Santos
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D015925:Cryopreservation / Q000662:veterinary*; D004249:DNA Damage; D003670:Deer; D004822:Epididymis / Q000166:cytology*; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000008:administration & dosage*; D015227:Lipid Peroxidation; D008297:Male; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000032:analysis; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000737:chemistry / Q000187:drug effects* / Q000648:ultrastructure
chemical_list: D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide