Variações no perfil protéico e atividade antioxidante do plasma seminal e funções espermáticas associadas a potenciais condições de estresse térmico em bodes Saanen criados no nordeste do Brasil

Abstract

Seminal plasma proteins are involved in the regulation of different mechanisms associated with reproductive physiology. Thus, the present study was designed to investigate the protein profile and determine variations on catalase (CAT) and superoxide dismutase (SOD) antioxidant activity on seminal plasma from Saanen goats raised under tropical conditions, in different periods of the year. Semen from eight goats was collected along 12 months (during dry and wet seasons and transition periods), seminal plasma was obtained through by centrifugation and submitted to 2-D electrophoresis, as well as analyses of catalase (CAT) and superoxide dismutase (SOD) antioxidant activity. Gels were stained with colloidal Coomassie blue, scanned and analyzed using tools of the PDQuest software. Data were analyzed using randomized block designs to evaluate possible variations in the protein profile and antioxidant activity. Intensity of 34 spots of protein maps was significantly different among periods of the year. From these 34 spots, 19 spots were different between the dry and rainy periods. The expression of protein spots with values of kDa and pI similar to heat-shock protein (70 kDa), glutamate carboxypeptidase and arylsulfatase A proteins was higher during the dry period in comparison to rainy season, while the clusterin showed more intensity in the rainy period. The SOD antioxidant activity was higher in the seminal plasma (p<0.05) during the rainy/dry transition in comparison to rainy period. Also, CAT activity was lower in the rainy when compared to dry period. Considering the results obtained in the present study, we conclude that protein profile and antioxidant activity in the seminal plasma from Saanen goat breed raised under tropical conditions varies throughout the year, given that we observed more intensity of seminal plasma proteins and CAT activity in the period with higher environmental temperatures (dry/rainy transition and dry), coincident with decrease in the semen quality.