Adrenal aging and its effects on the stress response and immunosenescence

Normal aging is linked to various endocrine gland changes, including changes in the adrenal glands. Aging is linked to alterations of the hypothalamic-pituitary-adrenal (HPA) axis, including an increase in cortisol levels, a disruption of the negative cortisol feedback, and attenuation of cortisol's diurnal pattern. In addition, secretion of aldosterone and adrenal androgens [dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS)] from the adrenal cortex decreases with aging. In this review, we describe normal adrenal function, the adrenal response to stress and immunomodulation in aging individuals as well as the effects of adrenal aging on body composition, metabolic profile, bone health and cognition.