Steroidogenic factor 1 (SF1) is essential for pituitary gonadotrope function.

Area of Science:

• Endocrinology
• Reproductive Biology
• Molecular Genetics

Background:

• Steroidogenic factor 1 (SF1) is a nuclear receptor crucial for adrenal and gonadal development.
• Global SF1 knockout mice display complex endocrine defects, obscuring its direct role in specific tissues like the pituitary.
• The precise function of SF1 in pituitary gonadotropes remains uncertain due to confounding systemic effects.

Purpose of the Study:

• To elucidate the specific role of SF1 in pituitary gonadotropes.
• To create a mouse model for studying pituitary-specific SF1 function.
• To investigate the impact of SF1 deficiency on gonadotropin expression and gonadal function.

Main Methods:

• Generated pituitary-specific SF1 knockout mice using Cre-loxP technology driven by the alpha-GSU promoter.
• Assessed reproductive phenotype, adrenal gland and VMH histology, and pituitary hormone levels.
• Evaluated gonadal response to exogenous gonadotropin treatment.

Main Results:

• Pituitary-specific SF1 knockout mice were viable but sterile with hypoplastic testes and ovaries.
• These mice exhibited normal adrenal and VMH histology but decreased luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels.
• Exogenous gonadotropin administration rescued gonadal maturation, confirming gonadotropin responsiveness.

Conclusions:

• SF1 plays an essential role in pituitary gonadotropes for normal reproductive function.
• Pituitary-specific SF1 knockout mice represent a valuable model for hypogonadotropic hypogonadism.
• SF1 is critical for the regulation of LH and FSH expression in the anterior pituitary.