Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

Effect of a pre-freezing treatment with cholesterol-loaded cyclodextrins on boar sperm longevity, capacitation dynamics, ability to adhere to porcine oviductal epithelial cells in vitro and DNA fragmentation dynamics

C. Tomás A , E. Blanch A , A. Fazeli B and E. Mocé A C
+ Author Affiliations
- Author Affiliations

A Centro de Tecnología Animal – Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA). Polígono ‘La Esperanza’, 100. Apdo. 187. 12400 – Segorbe (Castellón), Spain.

B Academic Unit of Reproductive and Developmental Medicine, Department of Human Metabolism,The Medical School, University of Sheffield. Level 4, The Jessop Wing, Tree Root Walk, Sheffield S10 2SF, UK.

C Corresponding author. Email: moce_eva@gva.es

Reproduction, Fertility and Development 25(6) 935-946 https://doi.org/10.1071/RD12079
Submitted: 13 March 2012  Accepted: 23 August 2012   Published: 5 October 2012

Abstract

The aim of this work was to examine how a pre-freezing treatment with cholesterol-loaded cyclodextrins (CLC) affects boar sperm longevity, capacitation dynamics, ability to bind to a porcine telomerase-immortalised oviductal epithelial cell line (TERT-OPEC) in vitro and DNA integrity dynamics after freeze–thawing. Although the samples treated with CLC exhibited lower sperm quality than the control samples (P < 0.05) immediately after thawing, these differences disappeared (P > 0.05) after long-term incubation (26 h at 37 or 16°C). Additionally, the CLC-treated spermatozoa underwent similar capacitation and DNA fragmentation dynamics as the control spermatozoa (P > 0.05). However, CLC-treated spermatozoa were better able to bind to TERT-OPEC in vitro (P < 0.0001). In conclusion, the pre-freezing treatment of boar spermatozoa with CLC enhanced the ability of the spermatozoa to bind to TERT-OPEC in vitro, which could have an effect on the establishment of the sperm reservoir in the ampullary­–isthmic junction in vivo. Additionally, frozen–thawed spermatozoa can be stored at 16°C for at least 6 h without a significant observable decline in sperm quality, which could be beneficial for the transport of thawed diluted doses of spermatozoa from the laboratory to the farm.

Additional keywords : capacitation, cell culture, cryopreservation.


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