Androgen effects on adipose tissue architecture and function in nonhuman primates

Area of Science:

• Endocrinology
• Metabolic Science
• Adipose Tissue Biology

Background:

• Androgens exhibit differential effects in men and women concerning insulin resistance and obesity.
• Mechanisms underlying sex-specific androgen action on adipose tissue are not well understood.
• Rodent and human responses to androgen imbalance may differ, necessitating studies in other models.

Purpose of the Study:

• To investigate the direct effects of gonadectomy and hormone replacement on white adipose tissue in nonhuman primates.
• To elucidate sex-specific mechanisms of androgen action in adipose tissue.
• To utilize an ex vivo approach for controlled studies of adipose tissue physiology.

Main Methods:

• Nonhuman primate model for in vivo studies of gonadectomy and hormone replacement.
• Ex vivo adipose tissue culture for controlled physiological experiments.
• Analysis of adipocyte morphology, gene transcription, and fatty acid uptake.

Main Results:

• Androgen deprivation in males led to smaller, multilocular white adipocytes but not obesity or insulin resistance.
• Testosterone replacement in males normalized adipocyte size, improved insulin sensitivity, and stimulated adipogenic gene expression.
• In females, androgens increased basal fatty acid uptake but reduced insulin-dependent uptake, with effects varying based on hormonal status.

Conclusions:

• Androgens are essential for normal adipogenesis and adipocyte function in males.
• Androgens can impair key adipocyte functions in females, demonstrating sex-specific effects.
• These findings provide a stronger experimental basis for understanding sex-specific androgen actions in adipose tissue.