The role of combining medroxyprogesterone 17-acetate with human menopausal gonadotropin in mouse ovarian follicular development

Abstract

Medroxyprogesterone 17-acetate (MPA) combined with human menopausal gonadotropin (hMG) has been effectively used for ovarian stimulation in clinical practice. However, the molecular mechanism of MPA + hMG treatment in follicular development is poorly described. Here we performed a study to investigate the impact of MPA + hMG on ovarian stimulation utilizing a mouse model in vivo. Forty female BALB/C mice were randomly divided into four groups of 10 each and treated during ciestrus stage and continued for 5 days: control group, MPA group, hMG group, and MPA + hMG group. Morphological and molecular biology methods were used for detecting serum hormones and ovarian function. MPA + hMG group exhibited increasing follicle stimulating hormone (FSH), antral follicle, FSH receptor (FSHR) and phosphorylated mammal target of rapamycin (p-mTOR), and decreasing luteinizing hormone (LH), estradiol (E2), progesterone (P), corpus luteum, phosphoinositide 3-kinase (PI3K), Akt and mTOR compared with control group. In contrast, MPA + hMG group showed reduced FSH, LH, E2, P, corpus luteum, LH receptor (LHR), and activated PI3K,/Akt/mTOR pathway compared with hMG group (P < 0.05). Collectively, these data definitively established that MPA plus hMG may modulate the hormone, hormone receptor and PI3K/Akt/mTOR signaling pathway to influence follicular development in the mouse ovary. Our study provides overwhelming support for MPA + hMG as an effective treatment for infertility in women.

Figure 1

The establishment of MPA + hMG mice model.

Figure 2

The changes in serum FSH, LH, E2 and P levels. (A) The level of serum FSH, LH, E2 and P in control group before and after 5 days; (B) The levels of serum FSH, LH, E2 and P were detected after 5 days. *Represents MPA + hMG group vs control group, MPA group or hMG group. *P < 0.05, **P < 0.01, ***P < 0.001.

Figure 3

Effects of MPA + hMG on ovarian follicle development. Histologic sections were prepared from the ovaries of each group 24 hours after MPA or hMG treatment and stained with H&E, a detailed histopathological examination was performed under a light microscope noting each of the ovarian components. (A) Normal ovary of a control mouse. (B) The ovary with decreasing antral follicle and corpus luteum after MPA treatment. (C) The ovary with increasing corpus luteum after hMG treatment. (D) The ovary with increasing antral follicle and decreasing corpus luteum after MPA + hMG treatment. (E) The percentage of primordial follicle in four groups after 5 days of treatment. (F) The percentage of secondary follicle in four groups after 5 days of treatment. (G) The percentage of antral follicle in four groups after 5 days of treatment. (H) The percentage of corpus luteum in four groups after 5 days of treatment. Black arrows represent secondary follicle, yellow arrows represent antral follicle, green arrows represent corpus luteum. *Represents MPA + hMG group vs control group, MPA group or hMG group. *P < 0.05, ***P < 0.001.

Figure 4

The effects of treatment on ovarian FSHR, LHR, ER, and PR expression level. (A) The FSHR, LHR, ER, and PR were detected by immunohistochemistry, red arrows represent the expression of receptors. (B) The positive rate of FSHR, LHR, ER, and PR in four groups. *Represents MPA + hMG group vs control group, MPA group or hMG group. *P < 0.05.

Figure 5

The effects of treatment on the PI3K/AKT/mTOR signaling pathway in ovarian tissue. Ten samples were used for each western blot assay, and each sample was measured in triplicate. (A–C) Western analyses of PI3K and p-PI3K, and their statistical analysis in all groups. (D–F) Western analyses of AKT and p-Akt,, and their statistical analysis in all groups. (G–I) Western analyses of mTOR and p-mTOR,, and their statistical analysis in all groups. *Represents MPA + hMG group vs control group, MPA group or hMG group. *P < 0.05.