QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Tran, T. Articles by Linder, M. C. Search for Related Content PubMed PubMed Citation Articles by Tran, T. Articles by Linder, M. C.

---

Nutrient-Gene Expression

Dietary Iron Status Has Little Effect on Expression of Ceruloplasmin but Alters That of Ferritin in Rats^{1 ,2}

Department of Chemistry and Biochemistry and Institute for Molecular Biology and Nutrition, California State University, Fullerton, CA 92834-6866

³To whom correspondence should be addressed. E-mail: mlinder{at}fullerton.edu.

Evidence supports a role for ceruloplasmin (ferroxidase I) in the release of iron to the blood from mammalian cells. However, recent studies with cultured cells have suggested that it has the opposite effect, and that iron deficiency enhances expression of ceruloplasmin. We therefore examined in rats how nutritional iron status would affect expression of ceruloplasmin. Groups of male Sprague-Dawley rats were reared on a low iron, starch-based diet for 6–8 wk; half were supplemented by injection of iron dextran. At killing, hematocrits of deficient rats were half normal. Supplemented rats had normal liver concentrations of ferritin and ferritin iron. No ferritin was detected in the livers of the deficient rats. Northern analysis showed that ferritin L and H mRNAs were present in the deficient livers, but expression was half that of the normal rats. There was also twice as much copper. Levels of circulating ceruloplasmin (measured by rocket immunoelectrophoresis) were not altered by iron deficiency, although p-phenylenediamine oxidase activity and plasma copper were reduced 30%. In repeated studies, no differences in the expression of hepatic ceruloplasmin mRNA were detected. Treatment of rats of both sexes with additional iron (25 mg as iron dextran) 5–14 d before killing increased liver ferritin but did not alter liver ceruloplasmin mRNA expression or levels of circulating ceruloplasmin. We conclude that iron status is not an important factor in the expression of plasma ceruloplasmin made by the liver. However, it does have modest effects on steady-state levels of liver ferritin mRNA.

KEY WORDS: • iron deficiency • ceruloplasmin expression • ferritin expression • iron treatment • rats