Lipid peroxidation, assessed with BODIPY-C11, increases after cryopreservation of stallion spermatozoa, is stallion-dependent and is related to apoptotic-like changes.
Lipid peroxidation (LPO) of stallion spermatozoa was assessed in fresh semen and in samples of the same ejaculates after freezing and thawing. Particular attention was paid to individual differences in the susceptibility to LPO and its possible relationship with freezability. Innate levels of LPO were very low in fresh spermatozoa but increased after thawing, a change that was largely stallion-dependent. The level of LPO in fresh spermatozoa was not correlated with that of the thawed spermatozoa. Negative correlations existed between LPO and intact membranes post-thaw (r=-0.789, P<0.001), and also between LPO and spermatozoa with high mitochondrial membrane potential (Deltapsim) post-thaw (r=-0.689, P<0.001). LPO was also highly and significantly correlated with caspase activity. The correlation between caspase activity in ethidium positive cells and LPO was r=0.772, P<0.001. This LPO is unlikely to represent, per se, a sign of cryopreservation-induced injury, but it is apparently capable of triggering 'apoptotic-like changes' that could result in the sub-lethal cryodamage often seen among surviving spermatozoa.
Ortega Ferrusola
C
C
Section of Reproduction and Obstetrics, Laboratory of Spermatology, Department of Herd Health and Medicine, Veterinary Teaching Hospital, University of Extremadura, Avda de la Universidad s/n, Cáceres 10071, Spain.
González Fernández
L
L
Morrell
J M
JM
Salazar Sandoval
C
C
Macías García
B
B
Rodríguez-Martinez
H
H
Tapia
J A
JA
Peña
F J
FJ
D000818:Animals; D017209:Apoptosis; D001896:Boron Compounds; D002250:Carbon Radioisotopes; D020169:Caspases / Q000378:metabolism; D002470:Cell Survival; D015925:Cryopreservation / Q000662:veterinary*; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D005979:Glutathione Peroxidase / Q000378:metabolism; D006736:Horses; D015227:Lipid Peroxidation; D008297:Male; D053078:Membrane Potential, Mitochondrial; D008856:Microscopy, Fluorescence; D012662:Semen Preservation / Q000009:adverse effects / Q000662:veterinary*; D013094:Spermatozoa / Q000378:metabolism* / Q000473:pathology; D013482:Superoxide Dismutase / Q000378:metabolism
C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D002250:Carbon Radioisotopes; D005456:Fluorescent Dyes; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D020169:Caspases