Iron deficiency alters expression of genes implicated in Alzheimer disease pathogenesis

Brain Res. 2008 Oct 27:1237:75-83. doi: 10.1016/j.brainres.2008.07.109. Epub 2008 Aug 7.

Abstract

Neonatal brain iron deficiency occurs after insufficient maternal dietary iron intake, maternal hypertension, and maternal diabetes mellitus and results in short and long-term neurologic and behavioral deficits. Early iron deficiency affects the genomic profile of the developing hippocampus that persists despite iron repletion. The purpose of the present study was threefold: 1) quantitative PCR confirmation of our previous microarray results, demonstrating upregulation of a network of genes leading to beta-amyloid production and implicated in Alzheimer disease etiology in iron-deficient anemic rat pups at the time of hippocampal differentiation; 2) investigation of the potential contributions of iron deficiency anemia and iron treatment to this differential gene expression in the hippocampus; and 3) investigation of these genes over a developmental time course in a mouse model where iron deficiency is limited to hippocampus, is not accompanied by anemia and is not repletable. Quantitative PCR confirmed altered regulation in 6 of 7 Alzheimer-related genes (Apbb1, C1qa, Clu, App, Cst3, Fn1, Htatip) in iron-deficient rats relative to iron-sufficient controls at P15. Comparison of untreated to treated iron-deficient animals at this age suggested the strong role of iron deficiency, not treatment, in the upregulation of this gene network. The non-anemic hippocampal iron-deficient mouse demonstrated upregulation of all 7 genes in this pathway from P5 to P25. Our results suggest a role for neonatal iron deficiency in dysregulation of genes that may set the stage for long-term neurodegenerative disease and that this may occur through a histone modification mechanism.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Alzheimer Disease* / etiology
  • Alzheimer Disease* / genetics
  • Alzheimer Disease* / pathology
  • Alzheimer Disease* / physiopathology
  • Amyloid beta-Peptides / metabolism
  • Analysis of Variance
  • Anemia, Iron-Deficiency / complications*
  • Animals
  • Animals, Newborn
  • Cation Transport Proteins / genetics
  • Cell Differentiation / physiology
  • Disease Models, Animal
  • Female
  • Gene Expression Regulation, Developmental / drug effects
  • Gene Expression Regulation, Developmental / physiology*
  • Hippocampus / metabolism
  • Hippocampus / pathology
  • Male
  • Mice
  • Mice, Transgenic
  • Microarray Analysis / methods
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism
  • RNA, Messenger / metabolism
  • Rats

Substances

  • Amyloid beta-Peptides
  • Cation Transport Proteins
  • Nerve Tissue Proteins
  • RNA, Messenger
  • natural resistance-associated macrophage protein 1