title: Enzymatic scavengers in the epididymal fluid: comparison between pony and miniature breed stallions.
abstract: The use of stallion semen collected from cauda epididymis for AI has increased due to the new protocols available for cryopreservation. Preserving the genetic material from valuable males that suffer sudden death or other events that prematurely end the stallion's reproductive life is an important strategy for Stud breeding management. While protecting spermatozoa from oxidative stress and infectious agents, the epididymis promotes the enhancement of sperm cell morphology and changes in membrane protein profile, increasing its fertility potential. The epididymal fluid must be a balanced redox environment to allow sperm preservation and protein-protein and protein-lipids interactions to quantify. The aim of this study was quantify the enzymatic ROS scavengers in epididymal fluid of pony and miniature breed stallions. Epididymides from 8 pony stallions and 12 miniature breed stallions were dissected and fluid from caput, corpus and cauda epididymis collected. Spermatozoa were separated of epididymal fluid by 2-step centrifugation. The activities of catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured and compared between stallion groups and epididymal regions. The three enzymes were present in all epididymal regions tested, with higher activities of catalase and SOD in cauda epididymis in miniature breed stallions (P<0.05). GPx activity was higher in caput epididymis in pony stallions (P<0.05), however with no difference to fluid from cauda epididymis of both breeds. These results show a difference in antioxidant enzymatic scavengers between pony and miniature breed stallions. Also, our data confirm the protective role of cauda epididymis, preserving spermatozoa integrity from oxidative damage. As glutathione peroxidase is involved in several signaling pathways, its constant activity during epididymal transit corroborates the importance of this enzyme for spermatozoa maturation.
authors.affiliation: Laboratório de Biotecnologia, UNIVATES, Rua Avelino Tallini, 171, Lajeado 95000-000, RS, Brazil. Electronic address: ivanbustamante@univates.br.
authors.forename: Ivan Cunha
authors.initials: IC
authors.lastname: Bustamante-Filho
authors.affiliation: Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcellos, 2600, Anexo, Porto Alegre 90035-003, Brazil.
authors.forename: Andrea P
authors.initials: AP
authors.lastname: Rosa
authors.affiliation: REPROLAB, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9090, 91540-000 Porto Alegre, Brazil.
authors.forename: Liana S
authors.initials: LS
authors.lastname: Van der Linden
authors.affiliation: Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcellos, 2600, Anexo, Porto Alegre 90035-003, Brazil.
authors.forename: Carolina D
authors.initials: CD
authors.lastname: Pederzolli
authors.affiliation: Universidade Federal do Pampa, Rua 21 de Abril, 80, Dom Pedrito, RS, Brazil.
authors.forename: Adriana P
authors.initials: AP
authors.lastname: Neves
authors.affiliation: Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcellos, 2600, Anexo, Porto Alegre 90035-003, Brazil.
authors.forename: Carlos S
authors.initials: CS
authors.lastname: Dutra-Filho
authors.affiliation: REPROLAB, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9090, 91540-000 Porto Alegre, Brazil.
authors.forename: Maria Inês M
authors.initials: MI
authors.lastname: Jobim
authors.affiliation: REPROLAB, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9090, 91540-000 Porto Alegre, Brazil.
authors.forename: Rodrigo C
authors.initials: RC
authors.lastname: Mattos
mesh_terms: D000818:Animals; D001947:Breeding; D002374:Catalase / Q000378:metabolism; D004798:Enzymes / Q000378:metabolism*; D004822:Epididymis / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000378:metabolism; D006736:Horses / Q000378:metabolism; D008297:Male; D012661:Semen / Q000201:enzymology / Q000378:metabolism*; D053625:Sperm Retrieval / Q000662:veterinary; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D004798:Enzymes; D016166:Free Radical Scavengers; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase
keywords: Antioxidants; Enzymatic scavangers; Epididymis; ROS; Stallion