hrp0082p2-d1-409 | Growth Hormone | ESPE2014

Ternary Complex Formation and IGFBP3 Proteolytic Activity During Childhood: Age-Dependent Changes

Renes Judith S , van Doorn Jaap , Hokken-Koelega Anita C S

Background: IGF1 is mainly sequestered in a 150 kDa ternary complex with IGFBP3 and the acid-labile subunit (ALS). Dissociation of IGF1 from the ternary complex is in part regulated by proteolysis of IGFBP3, which reduces its affinity for IGF1. Short children born SGA have lower IGF1 and IGFBP3 levels compared to healthy peers.Objective and hypotheses: To determine complex formation in healthy normal statured children, and assess variables influencing co...

hrp0084fc7.3 | Growth-promoting therapies | ESPE2015

IGF1 Levels, Complex Formation, and IGF-Bioactivity in GH-Treated Children with Prader–Willi Syndrome

Bakker Nienke , van Doorn Jaap , Renes Judith , Donker Truus , Hokken-Koelega Anita

Background: Children with Prader–Willi syndrome (PWS) attain high serum immunoreactive IGF1 levels during standard dose GH treatment, which leads to concern, but lowering the dose, deteriorates their body composition.Objective and hypotheses: To evaluate serum IGF1, IGFBP3 and acid-labile subunit (ALS) levels, complex formation and IGF-bioactivity in GH-treated PWS children. We hypothesized that GH-treated children with PWS have a normal IGF-bioacti...

hrp0084p2-403 | GH & IGF | ESPE2015

Homozygous Carriers of a Novel IGFALS Mutation are 1.5 SD Shorter than Heterozygous Relatives and Tend to have Lower Bone Mineral Density

Isik Emregul , van Doorn Jaap , Demirbilek Huseyin , Losekoot Monique , Wit Jan-Maarten

Background: There are limited data on differences in height, bone mineral density (BMD) and pubertal delay between homozygous and heterozygous carriers of IGFALS defects.Objective and hypotheses: To describe clinical and laboratory features and BMD of homozygous and heterozygous carriers of a novel IGFALS mutation in a large Kurdish family.Method: Index cases were two first degree cousins presenting with short stature, low IGF1, ve...

hrp0092p1-367 | GH and IGFs (2) | ESPE2019

Normal IGF-Bioactivity and Low Free IGF-I in Patients with Prader-Willi Syndrome with High Total Serum IGF-I: Immunoreactive IGF-I Concentration Poorly Reflects IGF Bio-Activity and Bio-Availability.

Elizabeth Melitza , Donze Stephany , Pellikaan Karlijn , van den Berg Sjoerd , van Doorn Jaap , Peeters Robin P. , Hokken-Koelega Anita C.S. , de Graaff Laura C.G.

Introduction: Recombinant Growth Hormone (GH) has changed the lives of many patients with Prader-Willi Syndrome (PWS). GH treatment has beneficial effects on body composition, physical performance, cognition, psychomotor development, respiratory function and quality of life of patients with PWS. Due to the narrow therapeutic range, GH treatment is subject to strict limits. Clinicians measure serum immunoreactive Insulin-like Growth Factor 1 ('total IGF-I&#...