Maria Enlund-Cerullo1, Helena Hauta-Alus2, Saara Valkama2, Jenni Rosendahl2, Sture Andersson3, Outi Mäkitie4, Elisa Holmlund-Suila2. 1. Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Folkhälsan Research Center, Helsinki, Finland; Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Finland. Electronic address: maria.enlund@helsinki.fi. 2. Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Finland. 3. Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland. 4. Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Folkhälsan Research Center, Helsinki, Finland; Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Finland; Center for Molecular Medicine, Karolinska Institutet, Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden.
Abstract
BACKGROUND AND OBJECTIVES: Fibroblast growth factor 23 (FGF23) participates in phosphate, calcium and vitamin D metabolism. In children these interactions and modifying factors are largely unknown. PARTICIPANTS AND METHODS: This study evaluates temporal changes and modifiers of FGF23 concentrations from 12 to 24 months, in healthy children, participating in a randomized vitamin D intervention (VIDI). Participants received vitamin D3 of 10 or 30 μg/day from age 2 weeks to 24 months. At 12 and 24 months, growth measurements and venous blood samples were obtained for analyses of intact (iFGF23) and C-terminal FGF23 (cFGF23), 25-hydroxyvitamin D (25-OHD), calcium, phosphate, parathyroid hormone, iron and ferritin. Changes in FGF23 and modifying factors were examined by linear mixed models. RESULTS: The study included 594 infants. Girls had higher iFGF23 than boys (p < 0.001 for both 12 and 24 months), cFGF23 did not differ between the sexes. Adjusted mean iFGF23 decreased from 41.4 to 38.1 pg/mL in boys (p < 0.001) and from 45.2 to 42.5 pg/mL in girls (p = 0.002). Adjusted mean cFGF23 decreased from 2.89 to 2.00 pmol/L in boys (p < 0.001) and from 2.92 to 1.93 pmol/L in girls (p < 0.001). Iron modified FGF23 in both sexes, associating positively with iFGF23 and inversely with cFGF23. In girls, 25-OHD modified iFGF23. In boys, season modified FGF23, possibly through seasonal differences in 25-OHD. Vitamin D intervention dose did not affect FGF23. CONCLUSIONS: FGF23 decreases from 12 to 24 months. Girls have higher iFGF23 than boys, at both time points. Iron modifies FGF23 in both sexes.
BACKGROUND AND OBJECTIVES: Fibroblast growth factor 23 (FGF23) participates in phosphate, calcium and vitamin D metabolism. In children these interactions and modifying factors are largely unknown. PARTICIPANTS AND METHODS: This study evaluates temporal changes and modifiers of FGF23 concentrations from 12 to 24 months, in healthy children, participating in a randomized vitamin D intervention (VIDI). Participants received vitamin D3 of 10 or 30 μg/day from age 2 weeks to 24 months. At 12 and 24 months, growth measurements and venous blood samples were obtained for analyses of intact (iFGF23) and C-terminal FGF23 (cFGF23), 25-hydroxyvitamin D (25-OHD), calcium, phosphate, parathyroid hormone, iron and ferritin. Changes in FGF23 and modifying factors were examined by linear mixed models. RESULTS: The study included 594 infants. Girls had higher iFGF23 than boys (p < 0.001 for both 12 and 24 months), cFGF23 did not differ between the sexes. Adjusted mean iFGF23 decreased from 41.4 to 38.1 pg/mL in boys (p < 0.001) and from 45.2 to 42.5 pg/mL in girls (p = 0.002). Adjusted mean cFGF23 decreased from 2.89 to 2.00 pmol/L in boys (p < 0.001) and from 2.92 to 1.93 pmol/L in girls (p < 0.001). Iron modified FGF23 in both sexes, associating positively with iFGF23 and inversely with cFGF23. In girls, 25-OHD modified iFGF23. In boys, season modified FGF23, possibly through seasonal differences in 25-OHD. Vitamin D intervention dose did not affect FGF23. CONCLUSIONS: FGF23 decreases from 12 to 24 months. Girls have higher iFGF23 than boys, at both time points. Iron modifies FGF23 in both sexes.
Authors: Petra Loid; Helena Hauta-Alus; Outi Mäkitie; Per Magnusson; Riikka E Mäkitie Journal: Front Endocrinol (Lausanne) Date: 2022-09-08 Impact factor: 6.055