Associations of GHR, IGF-1 and IGFBP-3 expression in adipose tissue cells with obesity-related alterations in corresponding circulating levels and adipose tissue function in children
Elena Kempf,
Kathrin Landgraf,
Tim Vogel,
Ulrike Spielau,
Robert Stein,
Matthias Raschpichler,
Jürgen Kratzsch,
Wieland Kiess,
Juraj Stanik,
Antje Körner
Affiliations
Elena Kempf
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Kathrin Landgraf
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Tim Vogel
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Ulrike Spielau
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Robert Stein
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Matthias Raschpichler
Medical Faculty, Department of Paediatric Radiology, University of Leipzig, Leipzig, Germany
Jürgen Kratzsch
University of Leipzig, Medical Faculty, Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, Leipzig, Germany
Wieland Kiess
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Juraj Stanik
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Antje Körner
University of Leipzig, Medical Faculty, University Hospital for Children and Adolescents, Center for Pediatric Research, Leipzig, Germany
Components of the growth hormone (GH) axis, such as insulin-like growth factor-1 (IGF-1), IGF-1 binding protein-3 (IGFBP-3), GH receptor (GHR) and GH-binding protein (GHBP), regulate growth and metabolic pathways. Here, we asked if serum levels of these factors are altered with overweight/obesity and if this is related to adipose tissue (AT) expression and/or increased fat mass. Furthermore, we hypothesized that expression of GHR, IGF-1 and IGFBP-3 is associated with AT function. Serum GHBP levels were increased in children with overweight/obesity throughout childhood, while for IGF-1 levels and the IGF-1/IGFBP-3 molar ratio obesity-related elevations were detectable until early puberty. Circulating levels did not correlate with AT expression of these factors, which was decreased with overweight/obesity. Independent from obesity, expression of GHR, IGF-1 and IGFBP-3 was related to AT dysfunction,and increased insulin levels. Serum GHBP was associated with liver fat percentage and transaminase levels. We conclude that obesity-related elevations in serum GHBP and IGF-1 are unlikely to be caused by increased AT mass and elevations in GHBP are more closely related to liver status in children. The diminished AT expression of these factors with childhood obesity may contribute to early AT dysfunction and a deterioration of the metabolic state.
