Endocrine Abstracts

GH suppression during OGTT is the gold-standard test in diagnosis and monitoring of acromegaly. However, discrepancies between GH nadir and IGF-I have been described and have triggered search for factors modifying the extent of GH suppression. Cut-offs at 1.0 or 0.4 ng/ml are currently recommended with modern, highly sensitive GH assays. To establish assay specific GH nadir cutoffs for the 22kD GH specific IDS-iSYS assay, we examined 381 subjects (319 females, 62 males) with n...

Background: Recent studies reported high soluble α-klotho concentrations (α-klotho) in active acromegaly, with normalization after successful therapy. We showed that α-klotho correlates to GH and even better to IGF-I. So far, most studies employed an immunoassay from Immuno-Biological Laboratories (IBL) for measurement of α-klotho, but other assays are available. Agreement between assays remains questionable since α-klotho exists in several isoforms: K...

In an attempt to define novel genetic loci involved in the pathophysiology of primary aldosteronism a mutagenesis screen after treatment with the alkylating agent N-ethyl-N-nitrosourea was established for the parameter aldosterone. One of the established mouse lines with hyperaldosteronism was phenotypically and genetically characterized. Affected animals showed an increased aldosterone to renin ratio (males unaffected, 1.1±0.1 pg/ml per ng per ml per hour v...

Background: Soluble alpha klotho (sαKL) is high in active acromegaly, normalizes after disease control, and therefore is suggested as a new biomarker for growth hormone (GH) excess. However, little is known about the impact of biological variables other than GH.Methods: Serum sαKL (pg/ml) was measured by ELISA (IBL, Hamburg, Germany). We first evaluated pre-analytical stability, defined a reference interval for sαKL in healthy subjects (A:...

Background: Symptoms of hyperandrogenism are common in patients with Cushing’s disease (CD), but they cannot be sufficiently explained by measured concentrations of circulating androgens. In this study we analyzed the contribution of 11-oxygenated (11o×C19) androgens to hyperandrogenemia in female patients with CD as well as the influence of treatment with steroidogenesis inhibitors osilodrostat and metyrapone on 11o×C19 and classic androgens.<p class="abste...

Background: Alpha klotho is a transmembrane protein that regulates calcium metabolism. Its soluble portion has been linked to endocrine functions. We have recently shown high concentrations of serum soluble alpha klotho (sαKL) in active acromegaly. There is limited information about regulation of sαKL secretion. We aimed to gain insight about sαKL as a potential biomarker for H-related diseases.Methods: SαKL was measured by ELISA (IBL...

Primary aldosteronism (PA) describes the most frequent cause of secondary arterial hypertension. Aldosterone itself represents a BP-independent cardiovascular risk factor associated with increased rates of morbidity and mortality. Recently a worsening of lipid metabolism after treatment has been described.Objective: Our aim was to analyse changes in lipid parameters according to treatment outcome in PA patients. Data of 215 consecutive PA patients with u...

Aim: To determine diagnostic performance of normetanephrine (NMN) and metanephrine (MN) measured by an enzyme immunoassay (EIA) compared with liquid chromatographic–tandem mass spectrometry (LC-MS/MS).Methods: Subjects included 341 patients (174 males) with a mean age of 52 year (range 13–86) tested for PHEO, which was confirmed in 54 patients. Samples where collected from fasting patients after 30 min of supine rest and analyzed for NMN, MN an...

Ketogenic low-carbohydrate/high fat diets (LC-HFD) induce weight loss in both animals and humans. However, a number of unwanted side effects with these diets have been reported. We have previously shown in male rats that LC-HFDs negatively affect bone growth and bone mineral density, possibly due to macronutrient-induced impairments of the GH/IGF-system. Given the importance of dietary macronutrients in the regulation of bone density in male rats, in this study we investigated...

Background: Primary aldosteronism (PA) is a secondary form of arterial hypertension that – in case of unilateral disease – can be cured by surgery. Multiple studies have shown that PA patients are at higher risk to suffer from cardiovascular events and to develop metabolic diseases. Two thirds of patients with PA suffer from obstructive sleep apnea (OSA). A bi-directional, pathophysiological interplay between OSA and PA has been proposed, with focus on overnight ro...