title: Expression of growth differentiation factor 15 is not elevated in individuals with iron deficiency secondary to volunteer blood donation.
abstract: BACKGROUND
  Low serum hepcidin levels provide a physiologic response to iron demand in patients with iron deficiency (ID). Based on a discovery of suppressed hepcidin expression by a cytokine named growth differentiation factor 15 (GDF15), it was hypothesized that GDF15 may suppress hepcidin expression in humans with ID due to blood loss.
  
  
  METHODS
  To test this hypothesis, GDF15 and hepcidin levels were measured in peripheral blood from subjects with iron-deficient erythropoiesis before and after iron supplementation.
  
  
  RESULTS
  Iron variables and hepcidin levels were significantly suppressed in iron-deficient blood donors compared to healthy volunteers. However, ID was not associated with elevated serum levels of GDF15. Instead, iron-deficient subjects' GDF15 levels were slightly lower than those measured in the control group of subjects (307 +/- 90 and 386 +/- 104 pg/mL, respectively). Additionally, GDF15 levels were not significantly altered by iron repletion.
  
  
  CONCLUSIONS
  ID due to blood loss is not associated with a significant change in serum levels of GDF15.
authors.affiliation: Molecular Medicine Branch, NIDDK, Department of Transfusion Medicine, NIH, Bethesda, Maryland 20892, USA.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Tanno
authors.forename: Antoinette
authors.initials: A
authors.lastname: Rabel
authors.forename: Y Terry
authors.initials: YT
authors.lastname: Lee
authors.forename: Yu Ying
authors.initials: YY
authors.lastname: Yau
authors.forename: Susan F
authors.initials: SF
authors.lastname: Leitman
authors.forename: Jeffery L
authors.initials: JL
authors.lastname: Miller
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000032:analysis; D001782:Blood Donors; D005293:Ferritins / Q000097:blood; D055436:Growth Differentiation Factor 15 / Q000097:blood*; D064451:Hepcidins; D006801:Humans; D000090463:Iron Deficiencies; D014168:Transferrin / Q000032:analysis
chemical_list: D023181:Antimicrobial Cationic Peptides; D055436:Growth Differentiation Factor 15; C578702:HAMP protein, human; D064451:Hepcidins; D014168:Transferrin; D005293:Ferritins