Androgens and bone health

Osteoporosis is one of the most common metabolic bone diseases in the adult population and its prevalence will continue to rise as our population grow s older. In both sexes, hypogonadism is associated with accelerated loss of bone and development of osteoporosis. Adrenal and gonadal androgen levels decline with advancing age in both sexes. Androgens act by either directly binding to androgen receptors, or by aromatization of androgens to estrogen s and subsequently interacting with estrogen receptors. Both pathways are i mportant for skeletal health. Direct androgen binding to an androgen recept or may play a more important role in early skeletal development and determi nation of sexual dimorphic traits. While bone remodeling, which is importan t in maintaining healthy bone through life, is primarily stimulated by estr ogen, studies in the rat and human support the complex action of androgens and estrogens in bone modeling and remodeling, and hence the development an d maintenance of healthy bone. In postmenopausal females, the addition of a ndrogens to hormone replacement therapy results in significant additional i mprovement in bone mineral density compared to estrogen replacement alone. Accumulating evidence indicate that androgens play an important role in the health of bone and the potential benefit of adding these agents to hormone replacement regimens.