Endocrine Abstracts

ACTH is the product of proteolytic processing of its precursor, proopiomelanocortin (POMC) and, in turn, is subject to proteolytic degradation. Regulation of proteolysis is crucial to several intracellular processes, including protein activation and inactivation, and thus contributes to active peptide concentrations. The proteosome 26S/ubiquitin system (UPS) is the main, non-lisosomial intracellular proteolytic pathway and alterations to this system have been observed in both ...

Retinoic acid, a derivative of vitamin A, has recently yielded promising results in the treatment of Cushing’s disease (Pecori Giraldi et al. JCEM 2012). Its main site of action appears to be the tumoural corticotrope as retinoic acid inhibits POMC transcription and corticotrope proliferation (Paez-Pereda et al. JCI 2001). Studies on tumoural adrenal cell lines have revealed an additional inhibitory effect on cell proliferation and stimulated co...

An increased prevalence of acromegaly and pituitary tumors has recently been observed in high industrial density areas (Cannavò et al. J Endocrinol 2010) or after dioxin exposure (Pesatori et al. Eur J Endocrinol 2008). These data as well as vitro studies on endocrine disruptors (EDs) suggest that environmental pollutants may affect hormonal secretion and pituitary cell proliferation (Blake et al. Proc Soc Exp Biol...

A 69-year-old woman developed hypertension, polyuria and hyperglycemia over the course of several months. The initial biochemical investigation revealed ACTH-dependent hypercortisolism (UFC 409.7 μg/24 h, NR 10–80; ACTH 43.3 pg/ml, NR 8–50; OST 28 μg/dl) and moderately elevated urinary catecholamines (E 80.5 μg/24 h, NR 2.5–33.6; norE 235.8 μg/24 h, NR 18.1–128.2). Further investigations disclosed absent ACTH and cortisol responses to CR...

Biochemical control of acromegaly is currently defined by the achievement of GH suppression after oral glucose tolerance test (OGTT) and of normal age- and gender-matched IGF1 levels. OGTT is believed to inhibit somatotropin secretion by enhancing central somatostatinergic tone; thus, the use of this test in evaluating biochemical control in acromegalic patients on somatostatin analogues (SSA) is questionable. To gain further insights into this topic, we analyzed basal and nad...

Glucocorticoids are known to exert a stimulatory action on white blood cell precursor proliferation but little is known on erythrocyte counts in patients with Cushing’s syndrome.Aim: Of the present study was to assess red and white blood cell parametres in a large series of patients with Cushing’s syndrome and follow the blood cell changes after postsurgical remission or persistence of hypercortisolism.Methods: Of 84 pati...

Background: QT interval reflects cardiac ventricular repolarization and, if prolonged, increases the risk of malignant arrhythmias such as torsade de pointes. QT interval duration is similar in boys and girls during childhood but shortens in males after puberty. In fact, reference limits for QTc in adults reflect this difference, i.e. lower than 460 ms in women and lower than 440 ms in men. Experimental studies suggest that testosterone is the major contributor to shortening o...

PreproTRH (178–199), a 22-aminoacid cleavage product of the TRH prohormone, has been postulated to act as an ACTH-releasing inhibitor. Indeed, in vitro evidence indicates that this peptide may inhibit basal and stimulated ACTH secretion in rodent anterior pituitary primary cultures and cell lines (Redei 1995, Revskoy 2001), although not all studies concur (Nicholson 1996). Aim of the present study was to test the effect of preproTRH(178–199) in human tumoral c...

Retinoic acid, a major modulator of adrenal development and differentiation, has also been shown to inhibit ACTH secretion by tumoral corticotropes. Recent clinical trials in patients with Cushing’s disease revealed that retinoic acid exerts beneficial effects in these patients (1, 2). Of note, the decrease in cortisol secretion during retinoic acid administration was more pronounced than the change in ACTH levels (1) suggesting a direct action at adrenal level. Aim of th...

Introduction: We have previously reported on the considerable variability in ACTH-secreting pituitary adenomas in terms of responses to major modulators in vitro (Pecori Giraldi et al J. Neuroendocrinol. 2011). Further studies revealed also differences in gene expression profiles in specimens analyzed by microarray analysis. Aim of this study is to correlate transcriptome expression pattern in archival human ACTH-secreting adenomas with clinical features of patients p...