Endocrine Abstracts

Growth hormone (GH) secretion is regulated by a complex interplay between GH-releasing hormone (GHRH), somatostatin and several other central and peripheral modulatory signals. Ghrelin has been hypothesized as physiological amplifier of GH pulsatility and acts via mechanisms, at least partially, independent of GHRH and somatostatin. The GH response to GHRH is strongly inhibited by previous administration of recombinant human GH (rhGH), likely as a consequence of a somatostatin...

Background: Obestatin, a ghrelin gene product was recently isolated but important questions remain regarding its regulation and its physiological effects. The aim of the present study was to evaluate the effect of unacylated ghrelin (UAG) on obestatin levels in normal subjects and patients with type 2 diabetes (T2D).Methods: Five normal subjects and 5 T2D patients were included in this study. Unacylated ghrelin (3 μg/kg per hour) or saline were cont...

Background: The activation of the GHS-R1a receptor by acylated ghrelin (AG) or by synthetic GH secretagogues (GHS), potently stimulates GH release and mediates other neuroendocrine/metabolic effects. Beta-adrenergic receptor agonists negatively influence GH secretion and other metabolic functions. The GH response to AG and GHS is refractory to the inhibitory effect of β2-adrenoceptors activation but no other report has evaluated the interactions between AG and salbutamol ...

Background: Obestatin is a 27 aa peptide derived from the ghrelin gene. Obestatin was first described to exert anorexigenic effects by decreasing gastric motility in rodent models, however these results have been debated and there is presently only small information regarding its activity and its regulation in humans. Furthermore, its interactions with acylated ghrelin (AG), derived from the same gene, have not been evaluated. Therefore, in these preliminary data, we sought to...

Background: Previous studies have shown that acylated ghrelin (AG) modulates insulin secretion and glucose disposal in vitro and after acute administration in humans. The aim of the present study was to evaluate postprandial glucose and insulin response following AG infusion in normal subjects and patients with type 2 diabetes.Methods: Six normal subjects and 3 patients with type 2 diabetes were included in this study. AG (1 μg/kg per h) or s...

In primary adrenal insufficiency hydrocortisone or cortisone are commonly used at doses of 30–37.5 mg/day as replacement therapy, though recent studies showed that cortisol normal production is about 5.7 mg/m2, equivalent to 20 mg/day of hydrocortisone, suggesting that supraphysiological doses are used. In 19 Addison’s disease patients (8 M, 11 F, 23–71 yr) under conventional glucocorticoid replacement therapy (37.5 mg cortisone/day) with low DHEAS le...

Cardiovascular (CV) diseases significantly contribute to the mortality excess observed in survivors of pediatric acute lymphoblastic leukemia (ALL) who received hematopoietic stem cell transplantation (HSCT). The study explores advanced glycation end-products (AGEs) levels, inflammatory status and lipid profile in a cohort of ALL survivors, in order to investigate their potential role in the pathogenesis of CV late effects. Inclusion criteria were: a) previous diagnosis of ALL...

Background: Primary aldosteronism (PA) is the most frequent form of secondary hypertension, with a high prevalence in resistant hypertension (RH), a condition of insufficient blood pressure (BP) control despite a 3-drug based treatment at full dose, including a diuretic. The prevalence of PAin refractory hypertension (ReH), a condition of persistently elevated BP values despite therapy with 5 drugs, is not known.Objective: To investigate the prevalence o...

Ghrelin circulates in two different forms. Acylated ghrelin (AG), a natural ligand of the GH Secretagogue receptor (GHS-R) type 1a, exerts several biologic central and peripheral actions including stimulation of GH secretion, but also modulation of insulin secretion, glucose and lipid metabolism. Unacylated ghrelin (UAG), despite unable to bind the GHS-R1a, is biologically active showing some influence in vitro and in vivo on glucose and lipid metabolism likely m...

Cortistatin (CST), a neuropeptide with high structural homology with somatostatin (SS), binds all SS receptor (SS-R) subtypes but, unlike SS, also shows high binding affinity to ghrelin (GRLN) receptor (GRLN-R). In humans CST exerts the same endocrine activities of SS, suggesting that the activation of the SS-R might mask the potential interaction with the GRLN system.CST-8, a synthetic CST-analogue devoid of any binding affinity to SS-R but capable to b...