Use of Bovine Serum Albumin as inductor of capacitation in deer red sperm

Abstract

Trabajo presentado al 18th International Congress of Animal Reproduction (ICAR), celebrado en Tours (Francia) del 26 al 30 de junio de 2016.The in vitro fertílization may be an important technology in farms of hispanicus red deer by the great availability of ovaries from hunted females. However, the knowledge about this assisted reproductive technique in this species is limited. The main problem is the need to use a non-defined substances as estrous sheep serum (ESS) to carry out the sperm capacitation. lt seems that EES induces cholesterol efflux, possibly for the action of albumin (BSA). The aim of this work was to study the effect of BSA on capacitation of red deerspermatozoa. Sperm samples from three males were collected by electroejaculation and subsequent frozen. Several BSA concentrations (0, 0.003, 0.1, 0.3, 1, 3, 10, 30 mg/mL) and a positive control with 20% EES (CEES) were added to synthetic oviductal fluid (SOF) and used as capacitation media. After thawing and incubation for 15 min in 5% C02 (four replicates), different sperm physiological parameters and protein tyrosine phosphorylation, as capacitation biomarker, were assessed. The effect of BSA concentration was studied by GLM-ANOVA analysis. The highest concentration of BSA (3, 10, 30 mg/ml) displayed (p<0.05) lower values of sperm motility (25.9; 19.4; 21.3 %), viability (32.6; 33.8; 32,5 %), mitochondrial activity (30.7; 30.7; 30.3) and acrosome integrity (32.4; 32.2; 30.3 %) in relation to CEES (35:5, 42.2; 36.5; 40.0 %, respectively). In addition, the presence of reactive oxygen species (ROS) was significantly higher with the lowest concentrations (0 and 0.003 mg/mL) of BSA (1543.5; 1858.6) in relation to 0.1, 0.3, 1, 3, 10,30 mg/ml of BSA (297.4; 179.5; 101.4; 78.7; 116.7; 42.5) and CEES (49.1). The effect of BSA and CEES on tyrosíne phosphorylation protein showed that one protein around 70 kDa was differently expressed between treatments displaying the lowest intensity (P<0.05) relativized tubuline, for 3, 10, 30 mg/ml of BSA and CEES (681, 0, 91, and 752 respectively) in relation to 0 and 0.003 mg/ml of BSA (1543 and 1858, respectively). In conclusion, the addition of BSA to capacitation media acts as potent antioxidant in a similar way to CEES. Moreover the expression of tyrosine phosphorylation protein was similar between the highest concentrations of BSA and CEES. Nevertheless, more studies are needed in relation to knowledge of the sperm fertilizatíon ability when BSA is present in the capacitation media since, many sperm parameters were negatively affected after addition of this protein.Peer Reviewe