DEHYDROEPIANDROSTERONE AND DISEASES OF AGING

Dehydroepiandrosterone (DHEA; prasterone) is a major adrenal hormone w ith no well accepted function. In both animals and humans, low DHEA le vels occur with the development of a number of the problems of aging: immunosenesence, increased mortality, increased incidence of several c ancers, loss of sleep, decreased feelings of well-being, osteoporosis and atherosclerosis. DHEA replacement in aged mice significantly norma lised immunosenescence, suggesting that this hormone plays a key role in aging and immune regulation in mice, Similarly, osteoclasts and lym phoid cells were stimulated by DHEA replacement, an effect that may de lay osteoporosis. Recent studies do not support the original suggestio n that low serum DHEA levels are associated with Alzheimer's disease a nd other forms of cognitive dysfunction in the elderly, As DHEA modula tes energy metabolism, low levels should affect lipogenesis and glucon eogenesis, increasing the risk of diabetes mellitus and heart disease. Most of the effects of DHEA replacement have been extrapolated from e pidemiological or animal model studies, and need to be tested in human trials, Studies that have been conducted in humans show essentially n o toxicity of DHEA treatment at dosages that restore serum levels, wit h evidence of normalisation in some aging physiological systems, Thus, DHEA deficiency may expedite the development of some diseases that ar e common in the elderly.