(Press-News.org) Scientists have been trying to explain the causes of diabetes for many years. Researchers at the University of Copenhagen and Novo Nordisk A/S have now shown that the increased activity of one particular iron-transport protein destroys insulin-producing beta cells. In addition, the new research shows that mice without this iron transporter are protected against developing diabetes. These results have just been published in the prestigious journal Cell Metabolism.
Almost 300,000 Danes have diabetes – 80 per cent have type-2 diabetes, a so-called lifestyle disease. The number of people with diabetes doubles every decade and the disease costs Danish society about DKK 86 million per day. People develop diabetes when the beta cells in their pancreas do not produce enough insulin to meet their body's needs. New research from the University of Copenhagen and Novo Nordisk A/S links this defect to one particular cellular iron transporter:
"Iron is a vital mineral for the healthy functioning of the body and is found in many enzymes and proteins, for example, the red blood pigment that transports oxygen. But iron can also promote the creation of toxic oxygen radicals. An increase in the iron content of the cells may cause tissue damage and disease. We find that increased activity of a certain iron transporter causes damage to the beta cell. And if we completely remove this iron transporter in the beta cells in genetically engineered mice, they are indeed protected against diabetes," explains Professor Thomas Mandrup-Poulsen, Department of Biomedical Sciences, The Faculty of Health and Medical Sciences.
Surplus iron increases diabetes risk
Together with Christina Ellervik, Associate Professor and Professors Børge Nordestgaard and Henrik Birgens from the University of Copenhagen, Thomas Mandrup-Poulsen has previously documented a connection between surplus iron and diabetes risk, based on large population studies. But this is the first time that scientists have found a link between inflammation and iron transport, which appears to be the underlying cause of the observed higher risk:
"We need to conduct controlled clinical trials showing that changes in the iron content of the body can reduce the risk of diabetes. Only then will we be able to advise people at risk of diabetes not to take iron supplements, or recommend drug treatment to reduce the amount of iron in the body," says Thomas Mandrup-Poulsen.
The evolutionary explanation
The team behind the scientific article in Cell Metabolism can see that the inflammatory signal substances created around the beta cells in both type-1 and type-2 diabetes accelerate the activity of the iron transporter.
"The evolutionary explanation of why the highly specialised beta cells are influenced by the inflammatory signal substances and contain the potentially dangerous iron transport proteins is presumably that the short-term increase in the amount of oxygen radicals is critical to the fine-tuning of insulin production during bouts of fever and stress. However, nature had not foreseen the long-term local production of signal substances around the beta cells, which we see in type-1 and type-2 diabetes," continues Thomas Mandrup-Poulsen.
The new results have implications for many scientists, not only those conducting research in diabetes. The beta cell can be used as a model for other cells that are particularly sensitive to iron, such as liver cells and cardiac-muscle cells.
###
Further information:
The paper will be under embargo until 12:00pm noon EST on Thursday September 20th, at which time the press release will be made available online at: http://news.ku.dk/all_news/2012/2012.9/cause-of-diabetes-may-be-linked-to-iron-transport/
Contact:
Professor Thomas Mandrup-Poulsen
Mobile: + 45 30 33 03 87
E-mail: tmpo@sund.ku.dk
Cause of diabetes may be linked to iron transport
2012-09-20
ELSE PRESS RELEASES FROM THIS DATE:
Pollen cells keep memory to control jumping genes
2012-09-20
In any living organism, all cells have the same DNA, but each cell's identity is defined by the combination of genes that are turned on or off, any given moment in time. In animals, this cellular memory is erased between generations, so that the new egg has no memory and, as such, has the potential to become any type of cell. In flowering plants, on the contrary, cellular memory passes from generation to generation, with potentially harmful implications for the development of new plants. In the latest issue of the journal Cell*, scientists from Instituto Gulbenkian de ...
Manipulating hormone receptors may help in the fight against obesity
2012-09-20
In the body's ongoing effort to maintain a healthy weight, an arsenal of cellular proteins called androgen receptors is critical for blocking fat accumulation. Now researchers reporting in the September issue of the Cell Press Journal Chemistry & Biology have discovered that naturally occurring steroids called glucocorticoids can thwart the receptors' activity, ultimately encouraging fat buildup.
"This has implications in this era of an obesity epidemic," says senior author Dr. Michael Mancini, from Baylor College of Medicine. "If you can reduce glucocorticoids, you might ...
Computer simulations for multiscale systems can be faster, better, more reliable
2012-09-20
EUGENE, Ore. -- (Sept. 20, 2012) -- University of Oregon scientists have found a way to correctly reproduce not only the structure but also important thermodynamic quantities such as pressure and compressibility of a large, multiscale system at variable levels of molecular coarse-graining.
The method is a mathematically driven predictive modeling of a real system, built on liquid state theory, and utilizing powerful computing resources. The team's theory appears in the Sept. 21 issue of the journal Physical Review Letters.
Understanding multiscale systems is of vital ...
Informatics approach helps doctors, patients make sense of genome data
2012-09-20
The cost of sequencing the entire human genome, or exome – the regions of the genome that are translated into proteins that affect cell behavior – has decreased significantly, to the point where the cost of looking at the majority of a patient's genomic data may be less expensive than undertaking one or two targeted genetic tests. While efficient, the acquisition of this much genetic data – in some cases as many as 1.5 to 2 million variants – creates other challenges.
In a paper that appears today in the advance online edition of Genetics in Medicine, researchers from ...
Commercial weight loss program evaluated
2012-09-20
Anyone who wants to lose weight has a wide variety of diets to choose from, but knowledge of what works is often poor. Researchers at Karolinska Institutet and Uppsala University have now evaluated a Swedish commercial weight loss programme called Itrim, and found it to be effective. After one year, participants had lost 11 kg on average.
"Most of the participants lost a lot of weight in the first three months and then showed very good weight stability after one year," says Erik Hemmingsson, researcher at Karolinska Institutet and Karolinska University Hospital's Obesity ...
Children in Switzerland are using mobile phones to go online
2012-09-20
On average, children in Switzerland are 9 years old when they use the internet for the first time. They spend on average 64 minutes per day online, which is substantially less than the European average (88 minutes). These are the results of a new study carried out by the Institut für Publizistikwissenschaft und Medienforschung (Institute of Mass Communication and Media Research) at the University of Zurich. The survey was conducted in the German-speaking and western part of Switzerland with 1,000 children and young people as well as one of their parents in each case.
Internet ...
Men and women are different in terms of genetic predispositions
2012-09-20
We are not all the same when it comes to illness. In fact, the risk of developing a disease such as diabetes or heart disease varies from one individual to another. A study led by Emmanouil Dermitzakis, Louis-Jeantet Professor at the Faculty of Medicine of the University of Geneva (UNIGE) reveals that the genetic predisposition to develop certain diseases may differ from one individual to another depending on their sex. Together with his collaborators, the professor has shown that genetic variants have a different impact on the level of gene expression between men and women. ...
Bergen-Belsen lessons underline vital role that nurses can play in patient feeding
2012-09-20
Nurses can play a key role in feeding people and restoring their humanity in times of great crisis and this was very evident during their little-known involvement in the liberation of Bergen-Belsen at the end of World War Two. That is the key finding of a historical research paper published in the October issue of the Journal of Clinical Nursing.
"Much has been written about the role of the armed forces and medical teams during this distressing time in our history, but the contribution of nurses is rarely mentioned when it comes to the liberation of this concentration ...
Humans were already recycling 13,000 years ago
2012-09-20
A study at the Universitat Rovira i Virgili and the Catalan Institute of Human Paleoecology and Social Evolution (IPHES) reveals that humans from the Upper Palaeolithic Age recycled their stone artefacts to be put to other uses. The study is based on burnt artefacts found in the Molí del Salt site in Tarragona, Spain.
The recycling of stone tools during Prehistoric times has hardly been dealt with due to the difficulties in verifying such practices in archaeological records. Nonetheless, it is possible to find some evidence, as demonstrated in a study published in the ...
A solution to reducing inflammation
2012-09-20
Research carried out at The University of Manchester has found further evidence that a simple solution, which is already used in IV drips, is an effective treatment for reducing inflammation.
The researchers also identified that hypertonic solution, which is a solution with an elevated concentration of salt, can ease inflammation purely through bathing in it – proving the Victorians were right to visit spa towns to "take the waters" for ailments like rheumatoid arthritis.
The research team, led by Dr Pablo Pelegrin, was investigating how cell swelling can control inflammation; ...