Johannes D. Veldhuis, MD


March 15, 2000

In This Article


The endocrine system regulates body composition, fat deposition, skeletal mass, muscle strength, metabolism, body weight, and physical well being. Multiple endocrine changes evolve with aging in all species and, not surprisingly, some of the physiologic manifestations of aging are related to the effects of declining hormone levels.

One of the earliest investigations into the possible role of the endocrine system in the aging process was conducted by Charles Edward Brown-Séquard (1817-1894), a French-educated physician and Professor of Physiology and Neuropathology at Harvard. At the age of 72 years, Brown-Séquard injected himself intramuscularly with the aqueous extracts of testicular tissue from young dogs and guinea pigs. In 1889, he proclaimed that this treatment produced an increase in grip strength and sexual vigor and advocated the medical use of testicular extracts as a means to prolong life.

In humans, aging is associated with a decrease in the gonadal production of estrogen in females (menopause) and testosterone in males (andropause); the adrenal production of dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEA-S) (adrenopause); and a decrease in the activity of growth hormone (GH)/insulin-like growth factor (IGF) axis (somatopause). As a result, hormone replacement regimens are being developed as a strategy to delay or prevent some of the consequences of aging. However, in some cases the use of hormone replacement therapy for this purpose is controversial. This article highlights pivotal new concepts in the endocrinology of aging, as discussed at a recent Serono Symposium, Endocrinology of Aging, held on October 27-30, 1999, in Tempe, Arizona.

Made possible through an unrestricted educational grant from Serono.