Changes in the expression of intestinal iron transport and hepatic regulatory molecules explain the enhanced iron absorption associated with pregnancy in the rat. Issue 5 (13th April 2004)

• Record Type: Journal Article
• Authors: Millard, K N; Frazer, D M; Wilkins, S J; Anderson, G J
• Is Part Of: Gut. Volume 53:Issue 5(2004)
• Page Start: 655
• Page End: 660
• Publication Date: 2004-04-13
• Subjects: duodenal cytochrome b -- divalent metal transporter 1 -- hereditary haemochromatosis -- iron regulation; Dcytb, duodenal cytochrome b -- DMT1, divalent metal transporter 1 -- GAPDH, glyceraldehyde 3-phosphate dehydrogenase -- HFE, the gene mutated in the most prevalent form of hereditary haemochromatosis -- Hp, hephaestin -- IRE, iron responsive element -- Ireg1, iron regulated mRNA (also known as ferroportin 1) -- NP, non-pregnant -- PP, post-partum -- RPA, ribonuclease protection assay -- TfR, transferrin receptor; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gut.2003.031153
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : Background: Iron absorption increases during pregnancy to cater for the increased iron requirements of the growing fetus. Aims: To investigate the role of the duodenal iron transport molecules and hepatic regulatory molecules in coordinating the changes in iron absorption observed during pregnancy. Methods: Rats at various days of gestation and 24–48 hours post-partum were examined for hepatic expression of hepcidin, transferrin receptors 1 and 2, and HFE (the gene mutated in the most prevalent form of hereditary haemochromatosis), and duodenal expression of divalent metal transporter 1 (DMT1), duodenal cytochrome b (Dcytb), iron regulated mRNA (Ireg1), and hephaestin (Hp) by ribonuclease protection assay, western blotting, and immunohistochemistry. Results: Decreased hepatic non-haem iron and transferrin saturation and increased expression of transferrin receptor 1 in the liver indicated a progressive reduction in maternal body iron stores during pregnancy. Duodenal expression of the iron transport molecules DMT1, Dcytb, and Ireg1 increased during pregnancy, and this corresponded with a reduction in hepcidin, HFE, and transferrin receptor 2 expression in the liver. Expression of all molecules returned towards control values by 24–48 hours post-partum. Conclusions: These data indicate that increased expression of key iron transport molecules is responsible for the elevated iron absorption associated with pregnancy, and implicate hepcidin, HFE, and transferrin receptor 2 in determining how the maternal iron homeostatic machinery responds to the increased iron demands accompanying gestation.