ESPE Abstracts

Introduction: The term lipodystrophy describes a rare disease subdivided into a heterogenous group of even rarer subforms. The rarity of this disease makes research in this area extremely difficult and international co-operation is mandatory to accumulate data sets of sufficient size. The European Consortium of Lipodystrophy (ECLip) consisting of an association of European experts in the field of lipodystrophy has therefore decided to set up a registry for patients with lipody...

Background: Recently, patients with severe obesity have been described due to functional leptin deficiency. This new entity is characterized by high immunoreactive levels of circulating leptin (Lep), but a reduced bioactivity of the hormone due to defective receptor binding (N Engl J Med 2015;372:48–54). Since these patients can be successfully treated with human recombinant leptin (metreleptin), a diagnostic tool to detect functional leptin deficiency is needed.<p cl...

Background: Leptin, primarily secreted by adipocytes, is a pivotal signal of the body's energy status and exhibits pleiotropic effects. Homozygous mutations in the leptin gene which result in defective synthesis, release or bioactivity, cause intense hyperphagia and early-onset severe obesity, along with multiple metabolic, hormonal, and immunological abnormalities. In vitro and animal model studies suggest that leptin plays a role in linear growth. So far...

Background: Severe early-onset obesity (SEOO) in children is more frequently observed in subjects with genetic disorders of which those of leptin pathway can be analyzed biochemically and genetically.Objectives: The aim of the study was to investigate anthropometrics and leptin parameters, specifically searching for bio-inactive leptin, in children with SEOO.Methods: Study cohort includes children ...

Objective: Merge and standardize the scarce data on molecular and phenotypic findings of mutations in the human leptin receptor (LEPR) gene causing a rare form of severe early-onset obesity.Methods: We summarized functional and phenotypic traits of LEPR mutations reported in the literature in a structured and comprehensive manner. Additional data was obtained from 6 subjects of our outpatient clinic not reported so far. Functionality of mutations was ass...

Background: Early-onset severe obesity due to leptin deficiency typically results from a defect of leptin production or secretion due to mutations in the leptin gene. Recently we described a new form of leptin deficiency caused by bioinactivity of the hormone and associated with high circulating leptin levels (New England Journal of Medicine 2015 372 48–54).Method: Serum leptin was measured by ELISA. The leptin gene was seq...

Introduction: Monogenic obesity refers to a group of rare, early-onset forms of obesity and accounts for about 7% of patients with severe pediatric obesity. Recent reports demonstrate the emerging role of Src-homology-2 (SH2) B adaptor protein 1 (Sh2b1), an important component in the leptin-melanocortin pathway, as a key regulator of leptin and insulin signaling, with possible roles in the pathogenesis of obesity and diabetes. SH2B1 deletions are found to be a...

Introduction: The soluble leptin receptor (sLR) is the main binding protein of leptin in the serum. It reflects the amount of membrane-bound leptin receptors (LEPR) as the sLR is produced by proteolytic cleavage of the extracellular domain of membrane-bound LEPR. Low sLR but high leptin levels were measured in patients with severe obesity. In patients with monogenic obesity caused by biallelic LEPR variants, sLR levels were found to be either undetect...

Background: Kinase suppressor of Ras 2 (KSR2) gene codes for a scaffold protein modulating intracellular pathways that involve MEK/BRAF cascade and AMPK signaling. KSR2 plays an important role in energy balance regulation, and KSR2 mutations were reported to be associated with obesity and insulin resistance in mice and humans. In transfected cells, several KSR2 mutations lead to impaired fatty acid oxidation, which improved under met...

Introduction: Monogenic defects in the leptin-melanocortin pathway result in hyperphagia and severe, early-onset obesity. Knowledge of the natural history of anthropometric parameters in patients with monogenic obesity is essential for diagnosis. However, reliable data on early childhood weight and height development in affected patients are lacking. This study aimed to evaluate the history of height, weight, and BMI development in early childhood in a Europea...