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RESEARCH ARTICLE

Effect of freeze–thawing process on lipid peroxidation, miRNAs, ion channels, apoptosis and global DNA methylation in ram spermatozoa

İbrahim Halil Güngör https://orcid.org/0000-0002-5250-1478 A * , Ahmet Tektemur https://orcid.org/0000-0002-2476-0413 B , Gözde Arkali C , Serap Dayan Cinkara A , Tutku Can Acisu A , Recep Hakkı Koca D , Ebru Etem Önalan B , Şeyma Özer Kaya A , Meltem Kizil C , Mustafa Sönmez A , Seyfettin Gür A , Zafer Çambay E , Abdurrauf Yüce C and Gaffari Türk A
+ Author Affiliations
- Author Affiliations

A Faculty of Veterinary Medicine, Department of Reproduction and Artificial Insemination, Fırat University, Elazığ, Turkey.

B Faculty of Medicine, Department of Medical Biology, Fırat University, Elazığ, Turkey.

C Faculty of Veterinary Medicine, Department of Physiology, Fırat University, Elazığ, Turkey.

D Faculty of Veterinary Medicine, Department of Reproduction and Artificial Insemination, Bingöl University, Bingöl, Turkey.

E Department of Medical Services and Technics, Fırat University, High School of Medical Services, Elazığ, Turkey.

* Correspondence to: vethalilgungor27@gmail.com

Handling Editor: James Cummins

Reproduction, Fertility and Development 33(14) 747-759 https://doi.org/10.1071/RD21091
Published online: 29 September 2021

© 2021 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

This study was carried out to investigate the effect of the semen freeze–thawing process on the functionality and molecular structure of ram spermatozoa. The temperature of pooled and diluted semen at 38°C (group 1, control) was lowered to 5°C (group 2), and it was subjected to glycerolisation–equilibration (group 3), frozen and thawed (group 4). Compared to the control, deterioration in spermatological parameters and significant increases in lipid peroxidation and global DNA methylation levels were observed in groups 3 and 4. When compared with the control, significant downregulation in the levels of miR-485 of group 2, miR-29a of group 3 and let-7a, miR-485 and miR-29a of group 4, and significant upregulation in the levels of miR-107 of group 3 and miR-127 of groups 3 and 4 were detected. In comparison to the control, significant upregulation in the levels of CatSper1, CatSper2, CatSper3, CatSper4, ANO1 and TRPM3 of group 2, CatSper4, ANO1 and TRPM3 of group 3 and KCNJ11 of group 4, and significant downregulation in the CatSper 3 level of group 4 were determined. As a result, the semen freeze–thawing process causes motility and morphological disorders in rams. This may be due to molecular changes associated with lipid peroxidation in spermatozoa.

Keywords: apoptosis, freeze–thawing, global DNA methylation, ion channels, lipid peroxidation, miRNA, ram semen, sperm characteristics.


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