Endocrine Abstracts

Subclinical Cushing’s syndrome (SCS) is a status of altered hypothalamo-pituitary-adrenal (HPA)-axis secretion in the absence of the classical signs or symptoms of overt cortisol excess. Among the various tests used for the diagnosis of SCS, the 1-mg dexamethasone test (DST) is the most used. Alprazolam (ALP), a benzodiazepine activating GABAergic receptors, possesses clear centrally-mediated inhibitory effects on ACTH and cortisol secretion in normal subjects, while it d...

Introduction: Hippocampus is a key area in the brain and influences the neuroendocrine functions, especially the hypothalamo–pituitary–adrenal (HPA) axis that is mainly regulated by corticotrophin-releasing hormone (CRH), vasopressin (ADH) and glucocorticoid (GC). This feed-back action is mediated by both glucocorticoid (GRs) and mineralocorticoid (MRs) receptors. GRs are distributed throughout the brain, but mostly in hypothalamic neurons, while the MRs highest expr...

Impaired GH secretion occurs in Cushing’s syndrome (CS), reflecting hypothalamic and pituitary alterations, without IGF-I impairment. Obesity is known to blunt GH release, leading to BMI-related tests for GHD. Evaluation of GH in CS after remission is difficult, due to chronic previous hypercortisolism and persistent overweight. Aim of this study was to evaluate in 22 patients with Cushing’s syndrome (16 Cushing disease, CD, 6 adrenal adenomas, CS) GH response to GHR...

Insulin tolerance test (ITT) is considered the golden standard test to evaluate HPA axis in suspected hypopituitarism. Low dose (1 μg) ACTH1–24 short stimulation test (LDSST) and metyrapone are often used when ITT is contraindicated. The diagnostic reliability of LDSST is, however, controversial, as even this dose has been considered supramaximal, while very low ACTH doses have been suggested more reliable to assess the adrenal sensitivity. Thus, in...

Interrelationships between HPA axis and sleep architecture are well documented and increased glucocorticoid levels seem associated with quantitative and qualitative sleep disruptions. The knowledge about sleep parameters in chronic hypercortisolism in humans is scanty. Our aim was to evaluate sleep efficiency in patients with Cushing’s syndrome (CS) at time of diagnosis, without ongoing specific therapy, using wrist actigraphy, a methodology that provides good estimations...

Cushing’s disease, i.e. cortisol excess due to an ACTH-secreting pituitary adenoma, is a rare disorder with considerable morbidity and mortality. Current therapeutic strategies include pituitary surgery, radiation, adrenalectomy and medical treatment with steroidogenesis inhibitors, as drugs aimed at the pituitary adenoma are as yet under investigation. Experimental data showed that retinoic acid restrains ACTH secretion by tumoral corticotrophes thus we decided to evalua...