ESPE Abstracts

Acute lymphoblastic leukemia (ALL) is the most prevalent cancer in childhood. Over the past decades, survival rates increased, but relapse is still associated with a poor prognosis, especially if the bone marrow (BM) is affected. Marrow adipose tissue (MAT) constitutes a major part of the BM niche, but its impact on normal hematopoiesis versus leukemia initiation, progression and relapse has only recently gained attention. MAT is very sensitive to changes in the patient’s...

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: Sclerostin is secreted by the osteocyte and inhibits bone formation by osteoblasts and is thus a negative regulator of bone formation. In adults, sclerostin levels increase after weight loss, which may be prevented by exercise training. The effect of weight loss on sclerostin in children is unknown.Objective and hypotheses: To compare sclerostin levels in children before and after a 10 weeks stay at a weight loss camp (WLC).<p class="abst...

Background: Adipose tissue is an important endocrine organ. Its secretion profile is robustly changed in the context of obesity fueling the development of comorbidities such as insulin resistance, diabetes mellitus type 2, and atherosclerosis. We have recently shown that the adipose tissue expression of the death ligand TNF-Related Apoptosis-Inducing Ligand TRAIL and its receptors is upregulated in obesity.Objective and Hypotheses: In this project, we in...

Background: Obesity is tightly associated with adipose tissue inflammation. Tumor necrosis factor-alpha (TNFα) has been identified as a key player in this inflammatory process and has been linked to the development of obesity-associated insulin resistance. Our group studies the involvement of TNF superfamily members in obesity-induced alterations in adipose tissue.Objective and hypotheses: Here, we aimed to identify the effects of the TNF superfamil...

Background: microRNAs (miRNAs) are a class of small (18–25 nucleotides), non-coding RNA molecules. They play an important role in the regulation of gene expression by either suppressing translation of genes or inducing their mRNA degradation. Several miRNA species are expressed in adipose tissue and involved in adipocyte function.Objective and hypotheses: Obesity leads to the infiltration of macrophages into adipose tissue causing local inflammation...

Background: POMC plays a major role in central body weight regulation. Recently we have shown that a POMC hypermethylation variant is significantly associated with obesity in children and adolescents (Kuehnen et al. PLoS Genetics 2012).Objective and hypotheses: Here we report about our extended studies to elucidate the mechanism behind the occurrence of the POMC hypermethylation variant in obese individuals.<p clas...

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: Studies in animal models revealed that brown and white adipocytes derive from different progenitor cells. Molecular characteristics of these cells have not been investigated in detail in humans.Objective and hypotheses: To identify novel markers of human brown adipocyte progenitor cells.Method: Progenitor cells from human paired deep neck and subcutaneous adipose tissue samples were obtained from n=12 subjects ...

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...