Investigating the impact of vitrification on bovine ovarian tissue morphology, follicle survival, and transcriptomic signature

Spyridon P Deligiannis; Keiu Kask; Vijayachitra Modhukur; Nina Boskovic; Marilin Ivask; Ülle Jaakma; Pauliina Damdimopoulou; Timo Tuuri; Agne Velthut-Meikas; Andres Salumets

doi:10.1007/s10815-024-03038-4

Investigating the impact of vitrification on bovine ovarian tissue morphology, follicle survival, and transcriptomic signature

J Assist Reprod Genet. 2024 Apr;41(4):1035-1055. doi: 10.1007/s10815-024-03038-4. Epub 2024 Feb 15.

Authors

Spyridon P Deligiannis^{1

2

3

4}, Keiu Kask^{5

6}, Vijayachitra Modhukur^{5

6}, Nina Boskovic^{7

8}, Marilin Ivask^{9

10}, Ülle Jaakma¹⁰, Pauliina Damdimopoulou^{11

12}, Timo Tuuri⁷, Agne Velthut-Meikas¹³, Andres Salumets^{14

15

16

17}

Affiliations

¹ Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Huddinge, 14186, Stockholm, Sweden. spyridon.panagiotis.deligiannis@ut.ee.
² Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, 14186, Stockholm, Sweden. spyridon.panagiotis.deligiannis@ut.ee.
³ Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu, 50406, Tartu, Estonia. spyridon.panagiotis.deligiannis@ut.ee.
⁴ Department of Obstetrics and Gynecology, University of Helsinki, 00290, Helsinki, Finland. spyridon.panagiotis.deligiannis@ut.ee.
⁵ Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu, 50406, Tartu, Estonia.
⁶ Competence Centre of Health Technologies, 50411, Tartu, Estonia.
⁷ Department of Obstetrics and Gynecology, University of Helsinki, 00290, Helsinki, Finland.
⁸ Department of Biosciences and Nutrition, Karolinska Institutet, 14183, Huddinge, Sweden.
⁹ Department of Pathophysiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 50411, Tartu, Estonia.
¹⁰ Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, 51014, Tartu, Estonia.
¹¹ Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Huddinge, 14186, Stockholm, Sweden.
¹² Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, 14186, Stockholm, Sweden.
¹³ Department of Chemistry and Biotechnology, Tallinn University of Technology, 12618, Tallinn, Estonia.
¹⁴ Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Huddinge, 14186, Stockholm, Sweden. andres.salumets@ki.se.
¹⁵ Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, 14186, Stockholm, Sweden. andres.salumets@ki.se.
¹⁶ Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu, 50406, Tartu, Estonia. andres.salumets@ki.se.
¹⁷ Competence Centre of Health Technologies, 50411, Tartu, Estonia. andres.salumets@ki.se.

Abstract

Purpose: Ovarian tissue cryopreservation is vital for fertility preservation, yet its effect on ovarian tissue follicle survival and transcriptomic signature requires further investigation. This study delves into the effects of vitrification on tissue morphology, function, and transcriptomic changes, helping to find possibilities for vitrification protocol improvements.

Methods: Ovarian cortex from 19 bovine animals were used to conduct pre- and post-vitrification culture followed by histological assessment, immunohistochemistry, and TUNEL assay. Follicles' functionality was assessed for viability and growth within the tissue and in isolated cultures. RNA-sequencing of ovarian tissue was used to explore the transcriptomic alterations caused by vitrification.

Results: Follicle density, cell proliferation, and DNA damage in ovarian stroma were unaffected by vitrification. However, vitrified cultured tissue exhibited reduced follicle density of primordial/primary and antral follicles, while freshly cultured tissue manifested reduction of antral follicles. Increased stromal cell proliferation and DNA damage occurred in both groups post-culture. Isolated follicles from vitrified tissue exhibited similar viability to fresh follicles until day 4, after which the survival dropped. RNA-sequencing revealed minor effects of vitrification on transcriptomic signatures, while culture induced significant gene expression changes in both groups. The altered expression of WNT and hormonal regulation pathway genes post-vitrification suggests the molecular targets for vitrification protocol refinement.

Conclusion: Vitrification minimally affects tissue morphology, follicle density, and transcriptomic signature post-thawing. However, culture revealed notable changes in vitrified tissue samples, including reduced follicle density, decreased isolated follicle survival, and alteration in WNT signalling and ovarian hormonal regulation pathways, highlighted them as possible limitations of the current vitrification protocol.

Keywords: Fertility preservation; Follicles; In vitro follicle culture; Ovarian tissue cryopreservation; Transcriptomics; Vitrification.

MeSH terms

Animals
Cattle
Cell Proliferation / genetics
Cryopreservation* / methods
DNA Damage / genetics
Female
Fertility Preservation / methods
Ovarian Follicle* / growth & development
Ovarian Follicle* / metabolism
Ovary* / metabolism
Transcriptome* / genetics
Vitrification*

Abstract

MeSH terms

Grants and funding