The daily rhythm of the hypothalamo-pituitary-adrenal (HPA) axis is regulated by the central clock in the suprachiasmatic nucleus. Cortisol, a glucocorticoid, acts as a secondary messenger between the central clock and the peripheral tissues. Changes in clock time, as seen in shift workers, alters the HPA axis and results in metabolic disturbances associated with ill health. Depression, anorexia nervosa and obstructive sleep apnoea, are associated with cortisol rhythm phase shifts and increased cortisol exposure. Higher nocturnal cortisol exposure is observed in patients with Cushing's syndrome and adrenal incidentalomas with autonomous cortisol secretion and is associated with insulin resistance, and increased cardiovascular risk and mortality. A decrease in cortisol rhythm amplitude is seen in adrenal insufficiency, and despite replacement, patients have an impaired quality of life and increased mortality. Research on cortisol replacement has focused on replacing the cortisol daily rhythm by subcutaneous hydrocortisone infusions and oral modified release hydrocortisone formulations with the aim of improving disease control and quality of life.

中文翻译：

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人体研究下丘脑-垂体-肾上腺（HPA）轴。

下丘脑-垂体-肾上腺（HPA）轴的每日节律由视交叉上核的中央时钟调节。皮质醇，皮质醇，在中央时钟和周围组织之间充当辅助信使。如轮班工人所见，时钟时间的变化会改变HPA轴，并导致与不良健康相关的代谢紊乱。抑郁症，神经性厌食症和阻塞性睡眠呼吸暂停与皮质醇节律相移和皮质醇暴露增加有关。库欣氏综合征和肾上腺偶发瘤伴有自主性皮质醇分泌的患者，夜间皮质醇的摄入量较高，与胰岛素抵抗相关，并增加了心血管疾病的风险和死亡率。肾上腺皮质功能不全患者的皮质醇节律幅度降低，尽管进行了替代治疗，患者的生活质量受损，死亡率增加。皮质醇替代的研究集中于通过皮下氢化可的松输注和口服调释氢化可的松制剂来替代皮质醇的每日节律，目的是改善疾病控制和生活质量。