Aging is without effect on the pituitary-adrenal axis in men

Area of Science:

• Endocrinology
• Aging Research
• Neuroendocrinology

Background:

• The hypothalamic-pituitary-adrenal (HPA) axis regulates stress response.
• Aging may alter HPA axis sensitivity and hormone secretion.
• Ovine corticotropin-releasing factor (o-CRF) is a key regulator of the HPA axis.

Purpose of the Study:

• To investigate the effects of o-CRF on hormonal secretions in young versus elderly males.
• To determine if aging impacts pituitary-adrenal sensitivity to CRF.
• To compare the time-dependent endocrine responses between age groups.

Main Methods:

• Healthy young and elderly males were administered o-CRF.
• Plasma levels of ACTH, cortisol, DHEA, and DHEA-S were measured over time.
• Hormonal responses to o-CRF were analyzed and compared between age groups.

Main Results:

• o-CRF significantly increased plasma ACTH, cortisol, and dehydroepiandrosterone (DHEA) in all subjects.
• No significant differences were observed in the time-dependent responses of ACTH, cortisol, and DHEA between young and elderly males.
• o-CRF did not significantly alter plasma dehydroepiandrosterone sulfate (DHEA-S) levels in any subjects.

Conclusions:

• Pituitary-adrenal sensitivity to hypothalamic CRF remains unchanged with aging in healthy males.
• The aging process does not appear to impair the acute endocrine response to CRF stimulation.
• These findings suggest preserved HPA axis function in elderly males regarding CRF responsiveness.