Vitrification and Subsequent In Vitro Maturation
of Mouse Preantral Follicles in Presence
of Growth Factors
Abstract
Objective
Cryopreservation of ovarian tissue or follicles has been proposed as an
alternative method for fertility preservation. Although successful vitrification of follicles has been reported in several mammalian species, the survival rate is generally
low. The aim of this study was to investigate the effects of fibroblast growth factor
(FGF) and epidermal growth factor (EGF) on
Materials and Methods
In this experimental study, preantral follicles with diameter of 150-180 µm were mechanically isolated from ovaries of 18-21 days old NMRI mice. Follicles were vitrified and warmed, then cultured in a-minimal essential medium (α-MEM) without growth factor supplementation as control group (group I), while supplemented with 20 ng/ml FGF (group II), 20 ng/ml EGF (group III), and 20 ng/ml FGF +20 ng/ml EGF (group IV). After 12 days, human chorionic gonadotrophin (hCG)/EGF was added to culture medium, and after 18-20 hours, the presence of cumulus oocyte complexes (COCs) and oocyte maturation were assessed. The chi-square (Χ2) test was used to analyze survival and ovulation rates of the follicles.
Results
Our results showed that the rate of metaphase II (MII) oocytes in FGF group
increased in comparison with control and other treatment groups (p<0.027), but there
was no difference between control with EGF and EGF+FGF groups in oocyte maturation rate (p>0.05). There was a significant decrease in survival rate of follicles in
EGF+FGE group in comparison with other groups (p<0.008). After
Conclusion
FGF has beneficial effect on oocyte maturation, and EGF increases
COCs number