Understanding the Role of Androgen Action in Female Adipose Tissue.

Adipose tissue is an important target of androgen action in humans. Androgens exert important effects on adipose tissue biology, including fat mass expansion and distribution, insulin signalling and lipid metabolism. In conditions of female androgen excess such as polycystic ovary syndrome (PCOS), androgens exert metabolically deleterious effects on adipose tissue function in a depot-specific manner. Androgen excess in women is metabolically deleterious, and adverse metabolic effects may be mediated by effects on preadipocyte differentiation and adipocyte hypertrophy. Circulating androgen burden correlates with adiposity in women, and drives visceral fat mass accumulation. Adipose tissue is also an important organ of pre-receptor androgen metabolism, and is host to a complex network of androgen activating and inactivating enzymes. Adipose androgen generation is increased in subcutaneous (SC) adipose tissue in women with PCOS, and intra-adipose concentrations of potent androgens may exceed those measured in peripheral circulation. Increased expression of the key androgen-activating enzyme aldo-ketoreductase type 1C3 in PCOS SC adipose tissue leads to high concentrations of testosterone and dihydrotestosterone. Enhanced local androgen generation may further contribute to the adverse metabolic profile of women with PCOS by exerting lipotoxic effects on local adipose biology.