Metabolism of Estrogen and Testosterone and Their Role in the Context of Metabolic Diseases

Sex hormones are steroid hormones and define the fundamental sexual differences between men and women. Production and secretion of sex hormones are regulated by negative feedback in the hypothalamus–pituitary–gonadal axis. The main biologic action of sex hormones exerts through nuclear receptors. The major female hormone is estrogen. Estrogen plays an important role in bone metabolism, whose main effect is inhibition of bone resorption and promotion of bone formation. The decrease of estrogen after menopause is the main contributor of osteoporosis in women, which results in sevenfold to tenfold higher risk of osteoporosis in postmenopausal women compared to men. Testosterone, the major male sex hormone, increases muscle mass and reduces visceral fat. Deprivation of testosterone for the treatment of prostate cancer increases the risk of obesity, type 2 diabetes mellitus (T2DM), and cardiovascular diseases (CVD). However, congenital adrenal hyperplasia and polycystic ovary syndrome, which are a state of hyperandrogenism in women, are associated with increased risk of T2DM and CVD.