Mitochondrial activity in fresh and frozen with and without α-tocopherol boar semen.?

SATORRE MERCEDES; BECONI MARTHA; BREININGER E; CÓRDOBA M

Jornada; IV Jornadas de INITRA; 2014

Ins. de Investigacion en Reproduccion animal INITRA

MITOCHONDRIAL ACTIVITY IN FRESH AND FROZEN WITH OR WITHOUT α-TOCOPHEROL BOAR SEMEN   SATORRE, MM, BECONI, MT, BREININGER, E, CORDOBA, M. Instituto de investigación y Tecnología en Reproducción Animal, Química Biológica, Facultad de Cs. Veterinarias, Universidad de Buenos Aires. Unidad ejecutora UBA-Conicet de Investigación en Producción Animal   Cryopreservation damage on sperm includes mitochondrial, flagellar and acrosomal alterations. The maintenance of the mitochondrial activity may be related to the resistance of sperm to the cryopreservation process. The plasma membrane disruption can lead to metabolic disorders. Sperm are relatively impermeable to di- and tricarboxylic acids. The alteration of the plasma membrane modified succinate permeability facilitating its mitochondrial oxidation. In order to evaluate the mitochondrial damage produced by the cryopreservation process we assessed in fresh (control) and cryopreserved with or without alpha tocopherol, boar spermatozoa, the mitochondrial functionality by the polarographic assay of oxygen uptake, as well as quality parameters: motility, by optical microscopy; viability by eosin-nigrosin; acrosomal integrity by DIC and Trypan blue staining patterns and cryocapacitation by chlortetracycline (CTC).. The results were analyzed by two-way ANOVA and posterior contrasts were used in the analysis of the mean values. A value of p≤0.05 was considered statistically significant. All quality parameters were affected by cryopreservation process, being this damage lower when alpha tocopherol was added to freezing extender. Basal respiration significantly decreased in cryopreserved samples respect to fresh ones, but was significantly higher in samples cryopreserved with alpha tocopherol, reaching values ​​similar to control (p>0.05). An increase (p<0.05) in succinate permeability was observed in all cryopreserved samples, although it was lower in samples with alpha tocopherol. The addition of alpha tocopherol to the freezing extender protects the sperm membranes from the oxidative damage produced by the cryopreservation process preserving the quality parameters and the mitochondrial activity.