Evaluation of the effects of high-dose follicle-stimulating hormone on mouse granulosa cells via Hippo pathway proteins (YAP1, TEAD3, and p73) and microRNAs (miR-129-5p and miR-145-5p)
Mahmut K. Özbilgin, Gulsen Z. KaramanObjective:
Exogenous gonadotropins are widely used to increases the number of available oocytes in both humans and animals. However, excessive or high-dose follicle-stimulating hormone (FSH) exposure may adversely affect follicular development. Ovarian hormones, growth factors, and miRNAs regulate cell proliferation and homeostasis through the Hippo pathway. Within this pathway, TEAD/YAP signaling promotes cell survival, whereas YAP/p73 regulates progression to apoptosis. We therefore investigated ovarian TEAD3, YAP1, and p73 expression levels, together with the related miR-129-5p and miR-145-5p. Expression of the apoptosis markers caspase-3 (casp3) and Bax was also evaluated for confirmation. This study aimed to determine the effects of high-dose FSH administration on granulosa cells on the Hippo pathway and their association with related miRNAs.
Methods:
Eighteen 4–6-week-old BALB/c female mice were divided into three groups: control, sham, and FSH. The FSH group was injected with 10-10-5-5 IU/mL FSH at 12-hour intervals (four total doses). An equivalent volume of saline was administered to the sham group. Animals were sacrificed 12 hours after the final injection. Ovarian tissues and blood samples were collected for analysis by quantitative polymerase chain reaction and immunohistochemical techniques.
Results:
YAP1 and TEAD3 expression levels were increased in ovarian granulosa cells after FSH administration, whereas p73, caspase-3, and Bax expression did not differ significantly among groups. miR-129-5p and miR-145-5p were downregulated in the FSH-treated group.
Conclusion:
The unchanged expression of p73, caspase-3, and Bax in granulosa cells indicates no progression to atresia after high-dose FSH administration. Increased YAP1 and TEAD3 expression, together with decreased miR-129-5p and miR-145-5p levels, indicated that proliferative activity predominated in the ovary; high-dose FSH likely exerted this effect through the Hippo pathway.