Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-2-24
pubmed:abstractText
Erythropoietin (Epo) is the central regulator of red blood cell production and acts primarily by inducing proliferation and differentiation of erythroid progenitor cells. Because a sufficient supply of iron is a prerequisite for erythroid proliferation and hemoglobin synthesis, we have investigated whether Epo can regulate cellular iron metabolism. We present here a novel biologic function of Epo, namely as a potential modulator of cellular iron homeostasis. We show that, in human (K562) and murine erythroleukemic cells (MEL), Epo enhances the binding affinity of iron-regulatory protein (IRP)-1, the central regulator of cellular iron metabolism, to specific RNA stem-loop structures, known as iron-responsive elements (IREs). Activation of IRP-1 by Epo is associated with a marked increase in transferrin receptor (trf-rec) mRNA levels in K562 and MEL, enhanced cell surface expression of trf-recs, and increased uptake of iron into cells. These findings are in agreement with the well-established mechanism whereby high-affinity binding of IRPs to IREs stabilizes trf-rec mRNA by protecting it from degradation by a specific RNase. The effects of Epo on IRE-binding of IRPs were not observed in human myelomonocytic cells (THP-1), which indicates that this response to Epo is not a general mechanism observed in all cells but is likely to be erythroid-specific. Our results provide evidence for a direct functional connection between Epo biology and iron metabolism by which Epo increases iron uptake into erythroid progenitor cells via posttranscriptional induction of trf-rec expression. Our data suggest that sequential administration of Epo and iron might improve the response to Epo therapy in some anemias.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
680-7
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Regulation of cellular iron metabolism by erythropoietin: activation of iron-regulatory protein and upregulation of transferrin receptor expression in erythroid cells.
pubmed:affiliation
Department of Internal Medicine, University Hospital, Innsbruck, Austria.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't