Gene expression pattern predictive of human ovarian follicle development and maturation

Area of Science:

• Reproductive Biology
• Endocrinology
• Molecular Biology

Background:

• Ovarian follicle maturation involves complex gene regulation for growth, differentiation, oocyte selection, and steroidogenesis.
• Granulosa cells from follicles of different sizes exhibit varying molecular profiles and functions.

Purpose of the Study:

• To compare gene expression patterns and intrafollicular steroid levels in granulosa cells from small antral follicles (SFs) versus large ovarian follicles (LFs).
• To evaluate differences between follicles of follicular and luteal origin, including those from conventional and DuoStim protocols.

Main Methods:

• Collected granulosa cells from small (<10 mm) and large (>16 mm) human ovarian follicles.
• Analyzed gene expression of developmental markers (e.g., LHCGR, FSHR, GPER, AMHR2, CCND2, CYP19A1).
• Assessed intrafollicular steroid levels and compared findings between conventional and DuoStim protocols.

Main Results:

• SFs showed higher expression of early antral markers (FSHR, GPER, AMHR2, CCND2, CYP19A1) compared to LFs.
• SFs demonstrated a greater capacity for androgen-to-estrogen conversion than LFs.
• Gene expression patterns and steroidogenic capabilities were consistent regardless of follicular or luteal origin.

Conclusions:

• Small and large ovarian follicles possess distinct molecular signatures, developmental markers, and steroidogenic functions.
• The ratio of follicle-stimulating hormone receptor (FSHR) to G protein-coupled receptor (GPER) effectively distinguishes mature from immature-like follicles.
• Follicle origin (follicular vs. luteal) does not significantly alter these observed differences.