title: Age-dependent expression of duodenal cytochrome b, divalent metal transporter 1, ferroportin 1, and hephaestin in the duodenum of rats.
abstract: OBJECTIVE
  The body's requirement for iron is different at different developmental stages. However, the molecular mechanisms of age-dependent iron metabolism are poorly understood. In the present study, we investigated the expression of iron transport proteins in the duodenum of Sprague-Dawley rats at five different age stages.
  
  
  METHODS
  Male Sprague-Dawley rats at postnatal week (PNW) 1, 3, 12, 44, and 88 were employed in the study. Serum iron status and tissue non-heme iron concentrations in the spleen, liver, bone marrow, heart, kidney, duodenal epithelium, and gastrocnemius were examined at each age stage. The expression of duodenal cytochrome b (DcytB), divalent metal transporter 1 (DMT1), ferroportin 1 (FPN1), hephaestin, and hepcidin were measured by real-time polymerase chain reaction or Western blot.
  
  
  RESULTS
  The levels of serum iron and transferrin saturation were higher in the rats at PNW1 and 3 than in those at PNW12, 44, and 88. Non-heme iron contents decreased from PNW1 to PNW3 and then increased thereafter. Duodenal DcytB, DMT1, and FPN1 increased to the highest level at PNW3 and then decreased from PNW12 to 88. The hepatic hepcidin mRNA level decreased to the lowest level at PNW3 and then increased with age.
  
  
  CONCLUSIONS
  Our findings showed that age had a significant effect on body iron status. The increased duodenal DcytB, DMT1, and FPN1 expression can enhance intestinal iron absorption to meet the high iron requirements in infants. Hepcidin or enterocyte iron levels may be involved in the regulation of age-dependent FPN1, DMT1, and DcytB expression in the duodenum.
authors.affiliation: Laboratory of Molecular Iron Metabolism, College of Life Science, The Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, Hebei Normal University, Shijiazhuang, Hebei Province, China; Bioreactor and Protein Drug Research and Development Center of Hebei Universities, Hebei Chemical and Pharmaceutical College, Shijiazhuang, Hebei Province, China.
authors.forename: Wei-Na
authors.initials: WN
authors.lastname: Kong
authors.forename: Qiong
authors.initials: Q
authors.lastname: Wu
authors.forename: Di
authors.initials: D
authors.lastname: Shen
authors.forename: Shu-E
authors.initials: SE
authors.lastname: Zhao
authors.forename: Pei
authors.initials: P
authors.lastname: Guo
authors.forename: Xiang-Lin
authors.initials: XL
authors.lastname: Duan
authors.forename: Yan-Zhong
authors.initials: YZ
authors.lastname: Chang
mesh_terms: D000375:Aging / Q000235:genetics* / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism*; D045303:Cytochromes b / Q000235:genetics* / Q000378:metabolism*; D004386:Duodenum / Q000378:metabolism*; D020895:Enterocytes / Q000378:metabolism; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D064451:Hepcidins / Q000378:metabolism; D007408:Intestinal Absorption / Q000235:genetics; D007501:Iron / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D014018:Tissue Distribution; D014168:Transferrin / Q000378:metabolism; D000098742:Ferroportin; D000099236:Solute Carrier Family 11, Member 2
chemical_list: D027682:Cation Transport Proteins; D045303:Cytochromes b; D064451:Hepcidins; D007501:Iron; D008565:Membrane Proteins; D014168:Transferrin; D000098742:Ferroportin; D000099236:Solute Carrier Family 11, Member 2; C492163:Heph, protein, rat
keywords: age; divalent metal-ion transporter 1; duodenal cytochrome b; duodenum; ferroportin 1; hepcidin; hephaestin