To print: Select File and then Print from your browser's menu --------------------------------------------------------------------------------------- Title: Scientists Identify Protein Essential For Iron Absorption URL: http://www.pslgroup.com/dg/58116.htm Doctor's Guide February 4, 1998
BUFFALO, NY -- February 4, 1998 -- A protein that is the single most critical known element in iron metabolism has been identified and characterised by scientists at the University at Buffalo and Children's Hospital in Boston, which is affiliated with Harvard University. The first protein to be identified as essential for normal intestinal iron absorption and the first mammalian iron transporter to be characterised at the molecular level, it appears to be involved in not just one, but several, critical roles in iron metabolism. The results are published in the Feb. 3, 1998 issue of the Proceedings of the National Academy of Sciences. "This finding allows us to take a major step forward in our understanding of iron metabolism," said Michael Garrick, Ph.D., professor of pediatrics and biochemistry at UB and co-author on the paper. The discovery of the protein, called Nramp2, will allow researchers to boost their understanding of iron-deficiency anemia, the most prevalent disease in the world, especially common in underdeveloped countries. It also will provide them with necessary information about ways to treat hemochromatosis, or iron overload, the most common recessively inherited disease, for which the usual treatment is the periodic bleeding of patients. The research highlights what the scientists describe as a stunning example of biological conservatism, where the same amino-acid change in the same gene in the same protein is responsible for iron-deficiency anemia in two different animal models. All cells in the body require iron to function, but the details of iron metabolism, particularly which proteins are specifically responsible for iron absorption in the intestine and iron traffic within cells, have long eluded researchers. The researchers said their results demonstrate that the protein is implicated in at least two, and probably three, important functions in iron metabolism. "The body has control mechanisms that maintain homeostasis in iron metabolism," Garrick explained. "So if you are iron-deficient, you're very efficient at absorbing iron from food. If you are iron-replete, then you will be much less efficient at iron uptake." The researchers have concluded that it is Nramp2 that actually takes up iron in the GI tract. Later, when iron is absorbed into cells in the body, it must be delivered to the mitochondria, the energy apparatus inside each cell where the heme in hemoglobin is made. "This protein also is the major one involved in this critical, intercellular traffic step," Garrick said. According to Laura Garrick, the results, as well as recent research conducted at the University of Western Australia at Nedlands, suggest that the protein also probably is implicated in a third type of iron transport, called nontransferrin-bound iron transport. This type of transport comes into play, she explained, when there is excess iron in the body, a condition that, if prolonged, can lead to abnormal iron deposits and health problems, such as cirrhosis of the liver and heart damage. --------------------------------------------------------------------------------------------- Copyright © 1999 P\S\L Consulting Group Inc. All rights reserved. Republication or redistribution of P\S\L content is expressly prohibited without the prior written consent of P\S\L. P\S\L shall not be liable for any errors, omissions or delays in this content or any other content on its sites, newsletters or other publications, nor for any decisions or actions taken in reliance on such content. --------------------------------------------------------------------------------------------- This news story was printed from *Doctor's Guide to the Internet* located at http://www.docguide.com --------------------------------------------------------------------------------------- Return to News Story Page This site is maintained by webmaster@pslgroup.com Please contact us with any comments, problems or bugs. All contents Copyright (c) 1998 P\S\L Consulting Group Inc. All rights reserved.