Ovarian transplantation for fertility preservation in a sheep model: can follicle loss be prevented by antiapoptotic sphingosine-1-phosphate administration?

Abstract

Aims. The aim of this study was to investigate whether sphingosine-1-phosphate (S1P), an apoptosis-inhibitor would be able to protect ovarian follicles from hypoxia-induced cell death in ovarian transplantation.

Methods. In four sheep, both ovaries were removed and immediately transplanted back into the abdominal wall. In two of them, one ovary was treated with S1P locally by injection and incubation after dissecting the ovarian cortex. The contra lateral ovary of both sheep and both ovaries of the remaining sheep served as controls. After 2 weeks, all grafts were evaluated histologically.

Results. Although the mean number of apoptotic cells were increased after grafting compared with fresh tissue, we were not able to demonstrate a significant difference regarding the follicular density in tissue with S1P treatment (mean number of follicles per field of view: 0.21 vs. 0.23, p = 0.909).

Conclusion. Apoptosis seems to play a role in follicular loss during ovarian transplantation; however, local application of S1P does not prevent primordial/primary follicles from hypoxia-induced cell death in cortical grafts in our study.

Keywords:

• Apoptosis
• S1P
• chemotherapy
• transplantation
• sheep