Endocrine Abstracts

Objective: Urinary cortisol and metabolites represents total cortisol production and metabolism. We assayed these metabolites to compared the information that could be extracted compared to the one provided by a sole cortisol assay.Design and patients: An inexpensive multiplex mass spectrometry assay was set up to quantify cortisol and its metabolites in 43 patients with benign secreting (AT+) or silent (AT−) adrenal tumours compared to 48 lean (Nl...

Objective: To extend knowledge about the clinical performances of a new chemiluminescent immunoassay (CLIA) for aldosterone set up in available analysers.Design and patient: We compared the results of a RIA assay to those of a CLIA assay in 198 serum and 80 urine samples from patients in endocrine and hypertension departments. Furthermore, for serum samples the concordance of results for postural tests was analysed.Results: RIA and...

Erythropoietin (EPO) is an oxygen-regulated hormone promoting the differentiation of erythroid progenitor cells. Apart from hypoxia, few data is available about EPO release by secretagogues including hormones. This retrospective study evaluated serum EPO concentrations in serum leftovers from subjects routinely investigated with various endocrine disorders displaying: peripheral hypothyroidism or hyperthyroidism, acromegaly, endogenous Cushing’s syndrome or non secreting ...

Background: According to the Endocrine Society’s guidelines, the screening and diagnosis of Cushing’s syndrome (CS) are based on the results of the overnight dexamethasone suppression test (DST), midnight salivary cortisol and 24-hour urinary free cortisol (UFC) measurements. These 3 tests reflect cortisol levels at the time of sampling without providing retrospective information. Hair cortisol concentration is a non-invasive way to measure cortisol exposure over lon...

Background: According to the literature, glucocorticoid receptor (GR) function is modulated by phosphorylation. Retinoic acid (RA) can activate some cytoplasmic kinases able to phosphorylate GR.Aim: As RA and glucocorticoids interact in neuronal cells, we investigated whether RA could modulate GR phosphorylation in such cells.Methods: HT-22 hippocampal cells were cultured 4d with or without dexamethasone (Dex, 10-6 M) or RA (10-6 M...

Brain ageing associates decreased neuronal plasticity, increased glucocorticoid and decreased retinoic acid (RA) signalling. We previously showed an interaction of these pathways on the regulation of a synaptic plasticity gene, BDNF. We thus investigated the effects of GC and RA on two BDNF-dependent genes: activity-regulated cytoskeleton protein (Arc) and Ca2+/calmodulin-dependent protein kinase II (CaMK). Dexamethasone (Dex, 10−6 M) and/or RA (10<...

Cortisol ([C]) biological activity depends on its free fraction diffusion into the intracellular compartment. The diagnosis of adrenal insufficiency requires investigations such as the synacthen test and studies in intensive care units suggest that free plasma [C] could provide a better indicator of efficient [C] than total plasma [C]. We undertook this study to compare various determinations of free [C] levels with regard to adrenal status evaluated on total plasma [C] after ...

Anti-Mullerian Hormone (AMH) is a 140 kDa gonadal glycoprotein of the TGFβ family, with two subunits linked by two disulfide bridges. Since a first assay in 1990, three generations of assays occurred: the 1st and 2nd were manual assays. The 3rd was automated: Access AMH Kits (Beckman Coulter) and Elecsys AMH (Roche). We had the opportunity to compare two new analysers with the Elecsys AMH: Vidas (Biomérieux) and Lumipulse G (Fujirebio). The later are one-step sandwic...

Background: Medical treatment with cortisol-lowering drugs is commonly used following pituitary surgical failure or recurrence of hypercortisolism in patients with Cushing’s disease (CD). Studies using late-night salivary cortisol (LNSF) measurement have shown persistent disruption of the circadian secretion of cortisol despite normalization of UFC in a subset of medically treated CD patients. Study aim Our objective was to assess the long-term cortisol exposure in CD pat...

The loss of nychthemeral rhythm is a feature of endogenous hypercorticism that may be investigated by the assay of midnight salivary cortisol (serC0h) although often replaced by serum cortisol assay. However, manufacturers of cortisol immunoassays kits seldom provide reference values for this horary. We present here tentative reference values of serC0h with an automated imunoanalyzer (DXi800, Beckman Coulter).The population retrospe...