Searchable abstracts of presentations at key conferences in endocrinology

ea0014oc9.4 | Signal transduction | ECE2007

Signalling and internalisation properties of corticotrophin-releasing hormone (CRH) receptor type 2

Markovic Danijela , Lehnert Hendrik , Grammatopoulos Dimitris

The family of urocortins (UCNs) exert important pathophysiological actions in the control of peripheral homeostatic mechanisms, through activation of the type 2-corticotropin releasing hormone receptor (CRH-R2). This G-protein coupled receptor preferentially binds urocortins (UCN, UCNII and UCNIII) than CRH. In most tissues, CRH-R2 activation leads to increased cAMP production. In this study we used HEK293 cells stably overexpressing recombinant CRH-R2β receptors to inves...

ea0041gp129 | Obesity | ECE2016

Direct effects of dopamine on mitochondrial thermogenesis in brown adipocytes

Kohlie Rose , Perwitz Nina , Lehnert Hendrik , Klein Johannes , Iwen Alexander

Brown adipose tissue (BAT) is key in energy homeostasis. Catecholamines are critically involved in the regulation of BAT-thermogenesis, yet current research has focussed on noradrenaline and adrenaline. Some evidence suggests a role of dopamine (DA) in BAT-thermogenesis but the intracellular mechanisms have not been addressed. We applied our extensively characterised murine brown adipocyte cell line to address these questions.D1-like and D2-like receptor...

ea0032p61 | Adrenal cortex | ECE2013

Severe hyperglycemia due to cortisol producing adrenal carcinoma

Harbeck Birgit , Berndt Matthias , Sufke Sven , Schutt Morten , Lehnert Hendrik

Introduction: Adrenal carcinomas are rare aggressive endocrine tumours with an incidence of 1–1.7 per 1 000 000. Sixty percent of patients present with symptoms of excess hormone secretion, most commonly as hypercortisolism, with or without virilisation due to accompanying androgen secretion. Tumours without clinical hormonal excess most often present with symptoms such as abdominal discomfort or back pain due to tumour growth.Case report: A 72-year...

ea0016p664 | Signal transduction | ECE2008

cAMP/PKA and ERK1/2 dependent feedback mechanisms regulating type 2 CRH receptor signalling

Markovic Danijela , Punn Anu , Lehnert Hendrik , Grammatopoulos Dimitris

Corticotropin-releasing hormone (CRH) and its related peptides, the urocortins (UCNs) mediate their effects by binding to two types of GPCRs, CRH-R1 and CRH-R2. In most target tissues, the adenylyl cyclase/cAMP/PKA and the mitogen activated protein kinase (MAPK) are the two main pathways mediating the biological effects of CRH-Rs. For most multi-signal G-protein coupled receptors (GPCRs), there is considerable level of ‘cross-talk’ between different signalling cascad...

ea0016p665 | Signal transduction | ECE2008

Signalling properties of corticotropin-releasing hormone receptor (CRH-R1/2) in adrenal (H295R) cells

Punn Anu , Ramanjaneya Manjunath , Lehnert Hendrik , Grammatopoulos Dimitris

Corticotropin-releasing hormone (CRH) and urocortins (UCN) bind to two types of GPCRs (CRH-R1 and CRH-R2), activating a plethora of signalling cascades, including the mitogen-activated protein kinases (MAPKs) pathways. Although previous studies have identified that CRH directly regulates adrenal steroidogenesis1, the second messenger systems and downstream effectors remain poorly defined. The adrenal cell line H295R, which express both CRH-Rs1 was used to...

ea0037ep610 | Obesity and cardiovascular endocrinology | ECE2015

Linking temperature to metabolism: the role of brown adipose tissue in humans

Backhaus Jenny , Rademacher Leonie , Iwen Alexander , Waltl Maren , Noll Melanie , Lehnert Hendrik , Schmid Sebastian M

The increasing prevalence of obesity is paralleled by related metabolic disorders such as insulin resistance and type 2 diabetes mellitus (T2DM). Extensive efforts across disciplines are made to reveal underlying mechanisms and develop effective therapies against obesity and its comorbidities. Since PET–CT studies provided evidence for functional brown adipose tissue (BAT) in adult humans, this specialized thermogenic compartment of adipocytes is in the focus of current r...

ea0034p263 | Obesity, diabetes, metabolism and cardiovascular | SFEBES2014

Renalase a key regulator of brown adipose tissue activity

Ramanjaneya Manjunath , Tan Bee , Patel Vanlata , Hu Jiamiao , Lehnert Hendrik , Hillhouse Edward , Chen Jing , Randeva Harpal

Renalase is a recently discovered flavin adenine dinucleotide (FAD)-dependent oxidase, predominantly secreted into the circulation from the kidney and regulates catecholamine degradation and metabolism. Renalase gene is also present in heart muscle, skeletal muscle and liver cells in humans, and in mouse testicles. Four isoforms of renalase gene has been identified in humans (hRenalase1 to hRenalase4), however only hRenalase1 is detected in human blood suggesting that hRenalas...

ea0032p534 | Endocrine tumours and neoplasia | ECE2013

Mitochondrial ultrastructure in pseudohypoxic succinate dehydrogenase B and von Hippel–Lindau gene mutation derived pheochromocytomas and paragangliomas

Tsokos Maria , Fliedner Stephanie , Prodanov Tamara , Abu-Asab Mones , Osman Jailan , Lehnert Hendrik , Pacak Karel

Mutations in the mitochondrial succinate dehydrogenase (SDH) subunits A, B, C, and D have been shown to hamper oxidative phosphorylation and predispose to pheochromocytomas (PHEOs) and paragangliomas (PGLs). These tumors are characterized by a glycolytic and pseudohypoxic phenotype, which is also seen in most PHEOs/PGLs occurring as part of von Hippel–Lindau (VHL) syndrome, due to VHL gene mutations. The rate of extra-adrenal tumor origin and malignancy however is particu...

ea0028p167 | Obesity, diabetes, metabolism and cardiovascular | SFEBES2012

The Hepatokine Fetuin-A is increased in PCOS women. Association with metabolic syndrome and regulation by metformin

Aghilla Mohamed , Adya Raghu , Tan Bee , Lehnert Hendrik , Ashawesh Khaled , Randeva Harpal

Introduction: Polycystic Ovary Syndrome (PCOS) is associated with insulin resistance, visceral obesity -metabolic syndrome (MS) and non-alcoholic fatty liver disease (NAFLD). Fetuin-A, human protein: α2-Heremans-Schmid glycoprotein is an abundant serum protein exclusively expressed in the liver and has been suggested to act as a link between obesity, insulin resistance (IR), and MS.Aims: A) To determine levels of Fetuin-A in PCOS women. B) To invest...

ea0019oc7 | Young Endocrinologist prize session | SFEBES2009

In vivo and ex vivo regulation of Visfatin production by leptin in human and murine adipose tissue: role of the PI3K and MAPK pathways

Tan Bee , Chen Jing , Brown James , Adya Raghu , Ramanjaneya Manjunath , Bailey Cliff , Lehnert Hendrik , Randeva Harpal

Apart from its role in energy storage, adipose tissue produces several hormones and cytokines termed ‘adipokines’ that have wide-ranging effects on carbohydrate and lipid metabolism; and thereby, play an important role in the pathogenesis of the metabolic syndrome. Visfatin is a novel adipokine, levels of which increase in obesity and is adipogenic; properties common to that of leptin. Thus, leptin may modulate visfatin production in adipose tissue. We investigated t...