Endocrine Abstracts

Androgens, by signaling through the androgen receptor (AR), mediate a wide range of male developmental processes. Complete androgen insensitivity syndrome (CAIS), a X-linked disorder caused by AR gene mutations, represents an in vivo model to study the role of androgens in sexual development. Here, we reported a case with CAIS at 20 weeks of gestational age harbouring a novel AR missense mutation (D767V), which was predicted to prevent androgen binding and...

The two main subtypes of pseudohypoparathyroidism (PHP), PHP-Ia and -Ib, are caused by mutations in GNAS exons 1–13 and methylation defects in the imprinted GNAS cluster, respectively. PHP-Ia patients show Albright hereditary osteodystrophy (AHO) and resistance toward PTH and additional hormones, while PHP-Ib patients do not have AHO and hormone resistance is limited to PTH and TSH. Recently, methylation defects have been detected in 5 patients with PHP-Ia, indicating a m...

Primary hyperparathyroidism (PHPT) is associated with increased risk of kidney stones. Hypercalciuria and urine oxalate excretion are considered risk factors for urolithiasis in PHPT stone-formers. Recently, the anion-exchanger SLC26A6 has been involved in the oxalate metabolism. Slc26a6-null mice showed hyperoxalemia, hyperoxaluria resulting in dramatic calcium oxalate urolithiasis. We tested the hypothesis that urine oxalate excretion in PHPT patients might be modulat...

A peculiar characteristic of parathyroid tissue is the ability to spontaneously induce angiogenesis, to proliferate and to secrete PTH when autotransplanted in patients undergoing total parathyroidectomy. Since stem/progenitor cells have been involved in the process of tissue regeneration, we searched for putative parathyroid progenitors from human normal and tumoral parathyroids. By immunohistochemistry, FACS analysis and cell culture we identified parathyroid cells positive ...

GH-secreting and non-functioning pituitary tumors are clinically distinct, usually benign but potentially locally aggressive lesions originating from the replication of a single mutated pituitary cell. As for the underlying genetic and epigenetic alterations, also the patterns of activation of specific signaling pathways as well as the prognostic molecular factors leading to local invasiveness are, to date, largely unknown. In this study, we used two-dimensional electrophoresi...

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)...

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...