Kutluturk, YesimAkinci, AysehanOzerol, Ibrahim HalilYologlu, Saim2024-08-042024-08-0420190334-018X2191-0251https://doi.org/10.1515/jpem-2018-0507https://hdl.handle.net/11616/98846Background: Obesity is known to cause metabolic disturbances including insulin resistance, dyslipidemia and alters bone mineralization. The effects of obesity on fibroblast growth factor 23 (FGF-23), which is important in bone mineralization, have not yet been clarified. Our aim was to investigate the association between FGF-23 concentration and obesity-associated dysmetabolism. Methods: Subjects comprised 46 obese children and adolescents. The same number of age-matched, healthy controls were recruited. Markers of bone mineralization and glucose metabolism were measured. Thyroid function and insulin resistance were investigated in both groups. In obese subjects; an oral glucose tolerance test (OGTT) was performed and hemoglobin A(1c) and lipid fractions were measured. Bone mineral density and hepatic steatosis were investigated. Results: Serum FGF-23, alpha-klotho and 1,25(OH)(2)D-3 concentrations were significantly lower while fasting insulin, fasting glucose, C-peptide and alkaline phosphatase (ALP) concentrations and homeostasis model assessment of insulin resistance (HOMA-IR) were significantly higher in the obese group compared to controls. A significant negative correlation was observed between free tri-iodothyronine (fT3) and both FGF-23 and alpha-klotho in the obese group. Significant negative correlation was found between FGF-23 and C-peptide and a positive correlation was found between FGF-23 and high density lipoprotein-cholesterol (HDL-c) in the obese subjects with impaired glucose tolerance (IGT). Significant negative correlations were found between FGF-23 and both fasting insulin levels and C-peptide levels in the obese subjects with hepatic steatosis. Conclusions: In our study, insulin resistance-associated hyperinsulinism and/or lower 1,25(OH)(2)D-3 levels, both present in obese children and adolescents, may lead to decreased serum FGF-23 concentrations in obese subjects.eninfo:eu-repo/semantics/closedAccessalpha-klothoFGF-23insulin resistanceobesityprediabetesArticle3277077143121168810.1515/jpem-2018-05072-s2.0-85068002620Q2WOS:000474203700007Q3