Ferrari E, Arcaini A, Gornati R, Pelanconi L, Cravello L, Fioravanti M, Solerte S B, Magri F
Department of Internal Medicine and Medical Therapy, Chair of Geriatrics, University of Pavia, P.zza Borromeo 2, 27100, Pavia, Italy.
Exp Gerontol. 2000 Dec;35(9-10):1239-50. doi: 10.1016/s0531-5565(00)00160-1.
The simultaneous evaluation of the circadian rhythm of plasma melatonin and ACTH and of serum cortisol and DHEAS represents a clinically reliable tool to appreciate the neuroendocrine changes occurring in physiological and pathological brain aging.A selective impairment of the nocturnal melatonin secretion has been observed in elderly subjects, being significantly related either to the age or to the severity of dementia. A significant increase of serum cortisol levels during evening- and night-times was found in elderly subjects, particularly if demented, when compared to young controls. Besides, both the circadian amplitude of cortisol rhythm and the nocturnal cortisol increase were significantly reduced in relation either to age or to cognitive impairment. By comparison to vascular dementia, patients with Alzheimer's disease exhibited the highest cortisol concentrations throughout the 24h. The sensitivity of the hypothalamic-pituitary-adrenal axis to the steroid feedback was significantly impaired in old subjects and particularly in the demented ones. The serum DHEAS levels were significantly lower in elderly subjects and even more in demented patients than in young controls. Consequently, a significant increase of the cortisol/DHEAS molar ratio was evident when going from young controls to healthy elderly subjects and to demented patients. In conclusion, the aging process affects many neuroendocrine functions resulting in subtle but clinically relevant consequences; the occurrence of senile dementia seems to play an additive role.
同时评估血浆褪黑素和促肾上腺皮质激素（ACTH）的昼夜节律以及血清皮质醇和硫酸脱氢表雄酮（DHEAS），是一种临床上可靠的工具，可用于了解生理和病理性脑老化过程中发生的神经内分泌变化。在老年受试者中观察到夜间褪黑素分泌存在选择性受损，这与年龄或痴呆严重程度均显著相关。与年轻对照组相比，老年受试者在傍晚和夜间血清皮质醇水平显著升高，尤其是患有痴呆症的老年受试者。此外，无论是与年龄还是认知障碍相关，皮质醇节律的昼夜振幅和夜间皮质醇升高均显著降低。与血管性痴呆相比，阿尔茨海默病患者在24小时内的皮质醇浓度最高。老年受试者，尤其是痴呆患者，下丘脑 - 垂体 - 肾上腺轴对类固醇反馈的敏感性显著受损。老年受试者的血清DHEAS水平显著低于年轻对照组，痴呆患者的血清DHEAS水平更低。因此，从年轻对照组到健康老年受试者再到痴呆患者，皮质醇/DHEAS摩尔比显著增加。总之，衰老过程会影响许多神经内分泌功能，导致细微但具有临床相关性的后果；老年痴呆症的发生似乎起到了累加作用。
