title: Serum fibroblast growth factor 21 levels are inversely associated with growth rates in infancy.
abstract: BACKGROUND
  Fibroblast growth factor 21 (FGF21) is a metabolic and growth regulator.
  
  
  OBJECTIVE
  To investigate the role of FGF21 during growth in infancy.
  
  
  METHODS
  Blood samples for FGF21, leptin, insulin and glucose were collected from cord blood obtained from 95 preterm and term newborns (cross-sectional group), and at 6 and 12 months of life in 80 preterm and term infants (longitudinal group). Length and weight were measured at birth, 6 months, and 12 months.
  
  
  RESULTS
  From birth through 12 months of age, preterm infants' linear growth and weight gain were larger than those of term infants, irrespective of birth weight SDS. At birth and at 12 months, there was no difference in FGF21 levels between preterm and term infants; in contrast, at 6 months, serum FGF21 in term infants was significantly higher than that of preterm ones. In the 0-6-month period, in the whole longitudinal group, serum FGF21 was inversely correlated to the length change SDS, and such a significant inverse correlation persisted in the preterm-AGA group in the 6-12-month period. In addition, term infants who experienced length catch-up in the first 6 months of life exhibited lower serum FGF21 levels at 6 months, and those with length catch-up growth between 6 and 12 months had a greater decrease of serum FGF21 level in the same time period.
  
  
  CONCLUSIONS
  Our results indicate that FGF21 in infancy is inversely correlated with linear growth rate, thus suggesting that FGF21 is a negative regulator of human growth.
authors.affiliation: Institute of Maternal and Child Research, Faculty of Medicine, University of Chile, Santiago, Chile.
authors.forename: Verónica
authors.initials: V
authors.lastname: Mericq
authors.forename: Francesco
authors.initials: F
authors.lastname: De Luca
authors.forename: Maria I
authors.initials: MI
authors.lastname: Hernandez
authors.forename: Veronica
authors.initials: V
authors.lastname: Peña
authors.forename: Katherine
authors.initials: K
authors.lastname: Rossel
authors.forename: Mirna
authors.initials: M
authors.lastname: Garcia
authors.forename: Alejandra
authors.initials: A
authors.lastname: Avila
authors.forename: Gabriel
authors.initials: G
authors.lastname: Cavada
authors.forename: German
authors.initials: G
authors.lastname: Iñiguez
mesh_terms: D001827:Body Height; D002657:Child Development; D005260:Female; D005346:Fibroblast Growth Factors / Q000097:blood*; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male
chemical_list: C414620:fibroblast growth factor 21; D005346:Fibroblast Growth Factors