hrp0089p2-p287 | Multisystem Endocrine Disorders P2 | ESPE2018

Endocrine Challenges in Patients with Thalassemia

Haamberg Tanja Christa , Schneider Christine , Rossler Jochen , Fluck Christa E

Introduction: Beta-thalassaemia is caused by point mutations leading to decreased production of beta-globin, which results in defective red blood cells and ineffective erythropoiesis. Complications are microcytic hypochromic anaemia, extramedullary haematopoiesis and increased intestinal iron absorption due to compensation mechanisms. The resulting iron overload can be aggravated by recurrent blood transfusions necessary for treatment of anaemia and may cause several endocrine...

hrp0084fc6.3 | Gonads & DSD | ESPE2015

Establishing the Role of the Steroid Backdoor Pathway for Androgen Biosynthesis in the Human Ovary

Marti Nesa , Sauter Kay S , Mullis Primus E , Fluck Christa E

Background: Recent work revealed two pathways in androgen biosynthesis, namely the classic and an alternative, the backdoor pathway. In this alternative pathway dihydrotestosterone is produced from 17-hydroxyprogesterone without the intermediacy of testosterone using mostly enzymes that are specific to the backdoor path. In the human ovary, regulation of androgen production plays a crucial role in normal physiology and in pathologies such as the polycystic ovary syndrome (PCOS...

hrp0084fc4.4 | Growth | ESPE2015

Modulation of GH-1 Splicing as Potential Strategy to Rescue GH Deficiency Type II

Miletta Maria Consolata , Fluck Christa E , Mullis Primus-E

Background: Isolated GH deficiency type II (IGHD II), the autosomal-dominant form of GH deficiency, is mainly caused by specific splicing mutations in the human GH (hGH) gene (GH-1). These mutations, occurring in and around exon 3, cause complete exon 3 skipping and produce a dominant-negative 17.5-kDa GH isoform that reduces the accumulation and secretion of wt-GH.Objective and hypotheses: As the severity of IGHD II inversely correlate...

hrp0089fc1.3 | Adrenals & HPA Axis | ESPE2018

Targetting the Binding of ACTH to the Melanocortin Receptor by Structure Modeling and Design of Peptide antagonists to Block Excess Androgens in 21-hydroxylase Deficiency

Parween Shaheena , Fluck Christa E , Pandey Amit V

Background: The adrenocorticotropic hormone (ACTH) is a 39 amino acid polypeptide secreted by the anterior pituitary and regulates cortisol secretion from the adrenal cortex. Cortisol has negative feedback and regulates the synthesis and secretion of the ACTH. Excess ACTH is associated with a wide range of diseases including congenital adrenal hyperplasia (CAH). Classic CAH due to the 21-hydroxylase (CYP21A2) deficiency causes a reduction or loss of cortisol synthesis. Here th...

hrp0089p2-p261 | Growth & Syndromes P2 | ESPE2018

Two Different Variants of Short Stature Homeobox-Containing Gene (SHOX) Mutation in the Same Family

Graf Stefanie , Santi Maristella , Losekoot Monique , Fluck Christa E.

Objectives: Deficiency of the short stature homeobox-containing (SHOX) gene is a potential etiology of short stature in children. The phenotypic spectrum of SHOX deficiency disorders, caused by haploinsufficiency of the SHOX-gene and inherited in a pseudo-autosomal dominant manner, is highly variable, even within the same family, ranging from nonspecific short stature to Leri-Weill dyschondrosteosis (LWD). Short stature, mesomelia and Madelung deformity define the classic clin...

hrp0086p1-p20 | Adrenal P1 | ESPE2016

HIV Drugs as a Possible Cause for Transient 21-Hydroxylase Deficiency in a Preterm Infant

Haamberg Tanja , Bullo Marina , McDougall Jane , Fluck Christa E.

Background: Transient neonatal adrenal dysfunction is reported in association with antiretroviral therapy with Lopinavir and Ritonavir. Other drugs have not been tested.Objective and hypotheses: We report on a preterm girl, born 26 weeks gestation, with elevated 17-hydroxyprogesterone (17OHP) at newborn screening. During pregnancy the mother was treated for HIV with Atripla (Efavirenz, Tenofovir, Emtricitabin) and viral load was suppressed. Furthermore t...

hrp0082p1-d3-188 | Pituitary | ESPE2014

Butyrate Stimulates GH Secretion From Rat Anterior Pituitary Cells Via the G-Protein-Coupled Receptors GPR41 and 43

Miletta Maria Consolata , Petkovic Vibor , Eble Andree , Ammann Roland , Fluck Christa E , Mullis Primus E

Background: Butyrate is a short-chain fatty acid closely related to the ketone body β-hydroxybutyrate (BHB) considered as the major source of energy during prolonged exercise. During fasting, when the liver switches to fatty acid oxidation, a rise in serum GH occurs concomitantly with the accumulation of BHB and short chain fatty acids (SCFA) acetate, propionate and butyrate. Interactions between GH, ketone body and SCFA during the metabolic adaptation to fasting are poor...

hrp0089p1-p214 | Sex Differentiation, Gonads and Gynaecology or Sex Endocrinology P1 | ESPE2018

In Silico and In vitro Studies of Human SRD5A2 Variants in Search for Activating Variants Explaining Androgen Excess Reveal Additional Loss of Function Variants

Katharopoulos Efstathios , Sauter Kay-Sara , Pandey Amit V , Fluck Christa E

Background: Androgens are steroid hormones necessary for human sex development. Testosterone (T) and the more potent dihydrotestosterone (DHT) are maybe the best known androgens, which exert their effect by binding and activating the androgen receptor. Steroid reductases 5α (SRD5As) catalyse the conversion of T to DHT in the classic androgen production pathway, or from 17-hydroxyprogesterone to 17OH-dihydroprogesterone, and androstenedione to androstanedione in alternate ...

hrp0089p2-p343 | Sex Differentiation, Gonads and Gynaecology or Sex Endocrinology P2 | ESPE2018

Clinical, Biochemical, Structural and Functional Characterization of a Novel P450 Oxidoreductase Mutation Causing Virilization in a 46,XX Patient

Camats Nuria , Benito-Sanz Sara , Parween Shaheena , Lopez-Siguero Juan-Pedro , Fernandez-Cancio Monica , Fluck Christa E , Udhane Sameer S , Kagawa Norio , Audi Laura , Pandey Amit V

Background: Cytochrome P450 oxidoreductase (POR) deficiency (PORD) is a form of congenital adrenal hyperplasia (CAH) and results in steroid-production loss from cytochrome P450 proteins. Mutations in POR cause mild to severe forms of CAH with/without bone malformation symptoms resembling Antley-Bixler syndrome. We report a novel POR Arg550Trp mutation identified in a 46,XX patient with signs of aromatase (ARO) deficiency. Child (first pregnancy) and mother pr...

hrp0082fc6.3 | Gonads & DSD | ESPE2014

LRH1 Rescues SF1 Deficiency for Steroidogenesis in vitro but Cannot Explain the Broad Phenotype of SF1 Deficiency in men

Camats Nuria , Fernandez-Cancio Monica , Audi Laura , Andaluz Pilar , Mullis Primus E , Carrascosa Antonio , Fluck Christa E

Introduction: Steroidogenic factor1 (SF1/NR5A1) regulates adrenal and sex development and function. SF1 mutations manifest with a broad phenotype; generally in 46,XY individuals with disorders of sex development (DSD) and in women with ovarian insufficiency. So far, no genotype–phenotype correlation has been found. We hypothesized that the broad phenotype of SF1 mutations may be due to a second hit in a gene with similar function. Liver receptor homolog-1 (LRH1/<...