Endocrine Abstracts

Pseudohypoparathyroidism (PHP) is a disorder characterized by hypocalcemia and hyperphosphatemia due to end-organ resistance to the action of PTH. The two main subtypes of PHP, PHP type Ia and Ib are caused by heterozygous loss-of-function mutations in GNAS exons 1–13, which encode Gsα, and by methylation defects in the imprinted GNAS cluster, respectively. Individuals affected with PHP-Ia typically show clinical abnormalities referred to as Albright hereditary osteo...

Somatostatin (SS) is a widely distributed polypeptide that exerts inhibitory effects on hormone secretion and cell proliferation by interacting with five different receptors (SST1-SST5), that display important differences in tissue distribution, coupling to second messengers, affinity for SS and intracellular trafficking. SS analogues currently used in the treatment of acromegaly inhibit hormone secretion and cell proliferation by binding to SST2 and 5. Beta-arrestins have bee...

Aim of this study was to evaluate the impact of rhGH treatment on glucose and lipid metabolism in in 26 patients (17M and 9F, age 47.0±11.1 years) with adult onset GH deficiency. Metabolic parameters (fasting glucose and insulin, glycated haemoglobin, lipid profile, body composition, OGTT) and indices of insulin resistance (IR) and sensitivity (IS), i.e. homeostasis model assessment (HOMA-IR and derived ISI-HOMA), quantitative insulin check index (QUICKI), ISI-composite, ...

Long-term effects of trans-naso-sphenoidal surgery (TNS) and long-acting somatostatin analogs (SSTa) on hypotalamic-pituitary-adrenal (HPA) function have been poorly investigated. Aim of the study was to evaluate over time the integrity of HPA axis in acromegalic patients with baseline preserved adrenal function and treated with one or both available treatments. We selected 23 patients (15F & 8M, age (±S.D.)=46.8±13.7 yrs) with normal (n=19)...

Primary HPT shows a great variability in its clinical course and severity, which might be related to polymorphic variants of the CASR gene. The aim of the study was to evaluate the frequency of two known CASR single nucleotide polymorphisms (SNPs), i.e. G/T at codon 986 and G/A at codon 990, in a homogenous North-Italian cohort of PHPT patients compared with a sex and age matched healthy population and the possible correlation of these CASR gene variants with the clinical and ...

Previous evidences have suggested that in adults with organic hypopituitarism the condition of GH deficiency (GHD) could mask the presence of other pituitary deficits. In our experience, both central hypothyroidism and hypoadrenalism were unmasked during rhGH therapy in adults with GHD due to central organic lesions. Few and conflicting information are available about the relationship among GHD, rhGH therapy and gonadal function. Aim of the present study was to investigate the...

The two regulatory subunits (R1 and R2) of PKA are differentially expressed in several cancer cell lines and studies indicate distinct roles for these subunits in growth control. Recently, mutations of the regulatory subunit 1A of PKA gene have been identified in patients with Carney complex (CNC). The aim of this study was to evaluate the expression of the different PKA regulatory subunits (R1A, R2A, R2B) in adrenocortical tumors not associated with CNC, as well as the effect...

Context: Available data on the natural history of pituitary incidentalomas (PI) are not strong enough to draw any evidence-based conclusion on timing and length of follow up of these masses, due to heterogeneity and low sample sizes.Objective: To describe the characteristics and the natural history of PI using data from a large cohort of patients investigated in two Italian Pituitary Centers.Patients and methods: Retrospective stud...

Dopamine receptor type 2 (DRD2) agonists (DAs) are the first-choice treatment for PRL-secreting pituitary tumors due to their efficacy in reducing tumor size and hormonal secretion. However, DAs are poorly effective in non-functioning pituitary tumors (NFPTs), despite most of them express DRD2. No correlation between DAs clinical responsiveness and DRD2 expression was found, suggesting post-receptor alterations underlying resistance. DRD2 signaling pathways that control cell p...

The cAMP signaling pathway plays a major role in the pathogenesis of cortisol-producing adrenocortical adenomas (CPA). In adrenocortical cells cAMP induces dramatic changes in cell morphology accompanied by actin cytoskeleton rearrangements that precede steroidogenesis, the causal relationship between these events being still undefined. In this study we investigated cAMP effects on cytoskeleton rearrangements and steroidogenic response in mouse (Y1) and human adrenocortical tu...