Much less widely known than the dangerous consequences of iron deficiencies is the fact that too much iron can also cause problems. The exact origin of the genetic iron overload disorder hereditary hemochromatosis (HH) has remained elusive.
In a joint effort, researchers from the European Molecular Biology Laboratory (EMBL) and the University of Heidelberg, Germany, have now discovered that HH is a liver disease. They report in the current issue of Cell Metabolism that the disorder develops when a crucial gene is lacking in liver cells.
Iron is essential for our body, because it is a central component of red blood cells. Too little iron can lead to dangerous anemias, but also too much iron can be detrimental as it promotes the formation of toxic radicals that lead to tissue damage. Hereditary hemochromatosis is an iron overload disorder that, affecting about one in 300 people, is probably the most common genetic disorder in Europe. Scientists have identified a gene, called HFE, that when mutated causes hemochromatosis in mice and humans. But as yet it is unknown in which tissue or organ the gene is acting to prevent iron overload.
A group of researchers around Matthias Hentze at EMBL and Martina Muckenthaler and Wolfgang Stremmel at the University of Heidelberg have now found that mice that are genetically engineered to lack HFE only in liver cells show all central features of the disease.
“For a long time scientists thought of HH as a disease of the intestine, because this is where iron uptake actually takes place,” says Matthias Hentze, Associate Director of EMBL. “Our research now reveals the crucial point is actually the liver and explains why HH patients suffer from increased iron absorption.”
HFE encodes a protein that is likely involved in transmitting signals about the current iron contents of the body to liver cells. In response to these signals, the liver cells make a special iron hormone, hepcidin that is released into the blood stream and reduces iron uptake in the intestine.
“HFE influences hepcidin expression through a series of intermediate molecules, but when the HFE gene is mutated the result is that less hepcidin is produced. This in turn means iron uptake in the intestine cannot be limited as effectively and an overload develops,” says Martina Muckenthaler, professor at the University of Heidelberg.
The research is a landmark for the joint Molecular Medicine Partnership Unit of EMBL and the University of Heidelberg. The Unit is dedicated to elucidating the molecular mechanisms of a range of different diseases, among which disorders of iron metabolism constitute a central focus.
Published in the 05 February, 2008 issue of Cell Metabolism.Anna-Lynn Wegener
Anna-Lynn Wegener | EMBL
Study tracks inner workings of the brain with new biosensor
16.08.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn
Foods of the future
15.08.2018 | Georg-August-Universität Göttingen
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
17.08.2018 | Physics and Astronomy
17.08.2018 | Information Technology
17.08.2018 | Life Sciences