Comparison of European eel sperm cryopreservation protocols with standardization as a target

[EN] The critical situation of the European eel (Anguilla anguilla) has urged the development of sperm cryopreservation protocols for reproduction in captivity and cryobanking. In the last years, two research groups have developed their own protocols in Spain and Hungary with positive results, but d...

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Detalles Bibliográficos
Autores: Herranz-Jusdado, Juan Germán, MORINI, MARINA, Rozenfeld, Christoffer, Kása, E., Kollár, T., Depincé, A., Labbé, C., Horváth, Á., Gallego Albiach, Victor|||0000-0002-9733-0625, Pérez Igualada, Luz María|||0000-0002-6678-7446, Asturiano, Juan F.|||0000-0002-6441-5294
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/120142
Acceso en línea:https://riunet.upv.es/handle/10251/120142
Access Level:acceso abierto
Palabra clave:Anguilla anguilla
Methanol
DMSO
DNA methylation
Epigenetics
ZOOLOGIA
PRODUCCION ANIMAL
Descripción
Sumario:[EN] The critical situation of the European eel (Anguilla anguilla) has urged the development of sperm cryopreservation protocols for reproduction in captivity and cryobanking. In the last years, two research groups have developed their own protocols in Spain and Hungary with positive results, but difficult to compare. Here, a series of experiments were conducted to test the quality of thawed sperm after using both protocols, determining which of them produce the best results and aiming for standardization. The quality of thawed sperm was assessed by studying the motility and kinetic values of thawed sperm from both cryopreservation protocols using a computer-assisted sperm analysis (CASA-Mot) system. In addition, a viability analysis was performed using flow cytometry to test if the cryoprotectants or the freezing-thawing process led to a reduction in spermatozoa survival. Furthermore, since during cryopreservation the sperm was treated with methylated cryoprotectants (DMSO or methanol) that may induce epigenetic changes in the sperm DNA (cytosine methylation) and could affect the offspring, we conducted a luminometric methylation assay (LUMA) to study the DNA methylation levels induced by both protocols. In this work, all the above-mentioned parameters were analyzed in fresh and frozen-thawed sperm samples. Our results showed that thawed sperm samples from both protocols presented lower sperm motility and velocity, and lower percentage of live cells than those shown in fresh sperm samples. Furthermore, sperm samples from the methanol based protocol showed significantly higher motility, velocity and percentage of live spermatozoa than the same sperm samples treated with the DMSO based protocol. In addition, the DMSO based protocol induced a hypomethylation of sperm DNA compared to fresh samples whereas the methanol based protocol did not alter sperm DNA methylation level. Our results indicate that the methanol based protocol is a more suitable protocol that preserves better the motility and genetic qualities of the European eel sperm.