Endocrine Abstracts

Pituitary tumors, are mostly benign, but may cause significant morbidity in affected patients, including visual and neurologic manifestations from mass-effect, or endocrine syndromes caused by hormone hypersecretion. Dopamine (DA) receptor DRD2 and somatostatin (SS) receptors (SSTRs) represent the main targets of pharmacological treatment of pituitary tumors since they mediate inhibitory effects on both hormone secretion and cell proliferation, and their expression is retained...

According to the WHO classification and to clinical practice most pituitary tumors are benign, although invasion and aggressive behavior, as well as resistance to somatostatin/dopamine (SS/DA) analogs, occur in 25 – 50% of cases. In particular, genetic forms of acrogigantism (X-linked acrogigantism - X-LAG) are characterized by a very precocious and resistant phenotype associated with microduplications in the Xq26.3 region involving the GPR101 gene. The GPR101 gene encod...

Pseudohypoparathyroidism type 1 A (PHP-1A) is a rare genetic disorder characterized by hypocalcemia, hyperphosfatemia, multi hormones resistance (PTH, TSH, Calcitonin, GH) associated with Albright hereditary osteodystrophy (AHO) features. The disease is caused by GNAS haploinsufficiency due to inherited inactivating mutation of GNAS-gene that codes for the stimulatory alfa subunit of G protein. A positive genotype-phenotype correlation was recently hypothesized. The purpose of...

Neurosurgery is the treatment of choice of non-functioning pituitary tumors (NFPAs), but its success is strongly affected by local invasion. Medical therapy is still under debate, although the use of cabergoline results in tumor shrinkage in a subset of patients. We recently demonstrated that dopamine receptor DRD2 agonist BIM53097 exerts cytostatic and cytotoxic effects in cultured cells from NFPAs, but no data are present in literature about DRD2 mediated effects on pituitar...

Since the first description of pseudohypoparathyroidism (PHP) a remarkable clinical variability was observed. In 2016 a new classification of this group of diseases have been published by the European Network on PHP and related disorders, proposing “inactivating PTH/PTHrP signaling disorder” (iPPSD) as a new term that encompasses all the clinical entities. PHP and related disorders vary in clinical presentation and disease severity, and clinical features usually deve...

Introduction: Glucagon stimulation test is one of the recommended growth hormone provocation tests for diagnosing growth hormone deficiency in children. In adult patients, recent data showed that glucagon administration is able to stimulate the release of copeptin, the stable C-terminal glycopeptide of the AVP prohormone whose evaluation during hypertonic saline infusion represents the gold standard for the differential diagnosis of polyuria/polydipsia. However, similar data o...

Background: Routine clinical use of arginine-vasopressin (AVP) is limited by its small molecular size and pre-analytical errors. In contrast, copeptin – a peptide of 39 amino acids co-secreted with arginine-vasopressin (AVP) - is a stable protein and its measurement represents a reliable measure of AVP concentration. The aim of this study was to analyze diagnostic role of copeptin in diagnosis of diabetes insipidus (DI) in patients treated for hypothalamic-pituitary disea...

Introduction: Pseudohypoparathyroidism (PHP) is a rare genetic disease characterized by renal resistance to parathyroid hormone (PTH), presenting with hypocalcemia, hyperphosphatemia and elevated PTH levels. We describe a PHP patient who presented with clinically significant hypercalcemia.Case description: A 46-year-old woman with a prior history of hypocalcemia presented to the emergency department with new-onset hypercalcemia, renal failure and anemia....

Pseudohypoparathyroidism type 1B (PHP-1B) is a rare, familial or sporadic, imprinting disorder due to the epigenetic dysregulation of the GNAS locus, whose main product is the α subunit of the stimulatory G protein (Gsα). Sporadic PHP-1B cases (spor-PHP-1B) display broad methylation abnormalities at multiple GNAS DMRs, but the underlying molecular mechanism is still unknown.Classically, PHP-1B patients show PTH and TSH resistance, but, in the p...

Non-functioning pituitary tumors (NFPTs), although benign in nature, frequently present local invasiveness that strongly reduces neurosurgery success. Medical therapy is still under debate, although dopamine (DA) receptor 2 (DRD2) agonists may induce tumor shrinkage in some patients. Aims of this study were: 1) to evaluate the effect of DR2D agonist BIM53097 on migration and invasion of NFPT cells, 2) to investigate the molecular mechanisms regulating the motility of these cel...