Article

Acute and chronic effects of developmental iron deficiency on mRNA expression patterns in the brain

Department of Neurosurgery, M.S. Hershey Medical Center, Hershey, USA.
Journal of neural transmission. Supplementum (Impact Factor: 1.07). 02/2006; 71(71):173-96. DOI: 10.1007/978-3-211-33328-0_19
Source: PubMed

ABSTRACT Because of the multiple biochemical pathways that require iron, iron deficiency can impact brain metabolism in many ways. The goal of this study was to identify a molecular footprint associated with ongoing versus long term consequences of iron deficiency using microarray analysis. Rats were born to iron-deficient mothers, and were analyzed at two different ages: 21 days, while weaning and iron-deficient; and six months, after a five month iron-sufficient recovery period. Overall, the data indicate that ongoing iron deficiency impacts multiple pathways, whereas the long term consequences of iron deficiency on gene expression are more limited. These data suggest that the gene array profiles obtained at postnatal day 21 reflect a brain under development in a metabolically compromised setting that given appropriate intervention is mostly correctable. There are, however, long term consequences to the developmental iron deficiency that could underlie the neurological deficits reported for iron deficiency.

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    • "Gene expression changes similar to those observed here may contribute to phenotypes involving movement impairment in various neurological disor- ders. There was very little overlap between the genes showing altered expression in response to iron supplementation and those identified in the microarray study by Clardy and colleagues (see Introduction), which investigated changes in rat brain gene expression in response to iron deficiency during development (Clardy et al., 2006). This suggests gene expression changes in adult iron overload are not simply the opposite of changes in developmental iron deficiency. "
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    • "IDA humans also have a reduced capacity to thermoregulate that is related to loss of thyroid function (Borel et al. 1991). In a gene array study from our laboratory on young rats, the TH-binding protein mRNA showed the greatest response to ID during development (Clardy et al. 2006b). Thus, there appears to be a significant impact of ID on the thyroid system from the level of mRNA to post-translational modification of proteins. "
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