title: Duodenal cytochrome b (Cybrd 1) and HIF-2α expression during acute hypoxic exposure in mice.
abstract: BACKGROUND
  Recent evidence suggests that the duodenum can regulate iron absorption independently of hepcidin via the transcription factor Hif-2α acting directly on the transcription of the proteins involved in the iron transport. The current study investigates the temporal relationship between Dcytb and Hif-2α during early hypoxic stimulus in the enterocyte in vivo.
  
  
  METHODS
  Duodenal Dcytb and Hif-2α protein expression was analysed by Western blot technique while gene regulation was determined by quantitative PCR.
  
  
  RESULTS
  Both Dcytb and Hif-2α protein expression were increased during the first hours of hypoxic duration. A change in hepcidin expression however, was significant only at 72 h hypoxia. Increased iron absorption reported in early hypoxia could be accounted for in part by the enhancement of Dcytb expression by Hif-2α in the duodenum.
  
  
  CONCLUSIONS
  Modulation of Hif-2α predominates over hepcidin in the regulation of intestinal iron absorption during short hypoxic duration. The intestine exerts regulatory mechanisms in the dietary absorption of iron into systemic circulation.
authors.affiliation: King's College London, Diabetes and Nutritional Sciences Division, School of Medicine, Franklin-Wilkins Building, London, SE1 9NH, UK. yemisi.latunde-dada@kcl.ac.uk
authors.forename: Gladys O
authors.initials: GO
authors.lastname: Latunde-Dada
authors.forename: Lan
authors.initials: L
authors.lastname: Xiang
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Simpson
authors.forename: Andrew T
authors.initials: AT
authors.lastname: McKie
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics* / Q000378:metabolism; D015153:Blotting, Western; D003573:Cytochrome b Group / Q000235:genetics* / Q000378:metabolism; D004386:Duodenum / Q000378:metabolism; D020895:Enterocytes / Q000378:metabolism; D005786:Gene Expression Regulation; D064451:Hepcidins; D000860:Hypoxia / Q000378:metabolism*; D007408:Intestinal Absorption / Q000235:genetics; D019266:Iron, Dietary / Q000493:pharmacokinetics; D008297:Male; D051379:Mice; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D023181:Antimicrobial Cationic Peptides; D051792:Basic Helix-Loop-Helix Proteins; D003573:Cytochrome b Group; D064451:Hepcidins; D019266:Iron, Dietary; D010088:Oxidoreductases; D000099162:Endothelial PAS Domain-Containing Protein 1; C579599:Hamp protein, mouse; C498909:Cybrd1 protein, mouse