[ RadSafe ] New research suggests how low doses of radiation can cause heart disease and strokerad
royherren2005 at yahoo.com
Fri Oct 23 01:35:00 CDT 2009
Public release date: 22-Oct-2009
Contact: Lucy Goodchild
lucy.goodchild at imperial.ac.uk
Public Library of Science
New research suggests how low doses of radiation can cause heart disease and stroke
A mathematical model constructed by researchers at Imperial College London predicts the risk of cardiovascular disease (heart attacks, stroke) associated with low background levels of radiation. The model shows that the risk would vary almost in proportion with dose. Results, published October 23 in the open-access journal PLoS Computational Biology, are consistent with risk levels reported in previous studies involving nuclear workers.
Cardiovascular disease is the leading cause of death and one of the leading causes of disability in developed countries, as reported in the paper and also by the World Health Organization (http://www.who.int/whosis/en/). For some time, scientists have understood how high-dose radiotherapy (RT) causes inflammation in the heart and large arteries and how this results in the increased levels of cardiovascular disease observed in many groups of patients who receive RT. However, in the last few years, studies have shown that there may also be cardiovascular risks associated with the much lower fractionated doses of radiation received by groups such as nuclear workers, but it is not clear what biological mechanisms are responsible.
The Imperial College London team, led by Dr. Mark Little, has explored a novel mechanism that suggests that radiation kills monocytes (a type of white blood cell) in the arterial wall, which would otherwise bind to monocyte chemo-attractant protein 1 (MCP-1). The resultant higher levels of MCP-1 cause inflammation which leads to cardiovascular disease. As well as being consistent with what is seen in nuclear workers, the changes in MCP-1 caused by dietary cholesterol that are predicted by the model are also consistent with experimental and epidemiologic data.
If the mechanism is valid it implies that risks from low dose radiation exposures (e.g., medical and dental X-rays), which until now have been assumed to result only from cancer, may have been substantially underestimated, say the authors.
The biological mechanism has yet to be experimentally tested. Further research is planned to investigate this.
FINANCIAL DISCLOSURE: The project was funded in part by the European Commission under contract FP6-036465 (NOTE). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
COMPETING INTERESTS: The authors have declared that no competing interests exist.
PLEASE ADD THIS LINK TO THE PUBLISHED ARTICLE IN ONLINE VERSIONS OF YOUR REPORT: http://dx.plos.org/10.1371/journal.pcbi.1000539 (link will go live upon embargo lift)
CITATION: Little MP, Gola A, Tzoulaki I (2009) A Model of Cardiovascular Disease Giving a Plausible Mechanism for the Effect of Fractionated Low-Dose Ionizing Radiation Exposure. PLoS Comput Biol 5(10): e1000539. doi:10.1371/journal.pcbi.1000539
Press Officer, Imperial College London
e-mail: lucy.goodchild at imperial.ac.uk
Telephone: +44 (0)20 7594 6702 or ext. 46702
Out of hours Duty Press Officer: +44 (0)7803 886 248
This press release refers to an upcoming article in PLoS Computational Biology. The release is provided by the article authors and their institutions. Any opinions expressed in this release or article are the personal views of the journal staff and/or article contributors, and do not necessarily represent the views or policies of PLoS. PLoS expressly disclaims any and all warranties and liability in connection with the information found in the releases and articles and your use of such information.
About PLoS Computational Biology
PLoS Computational Biology (www.ploscompbiol.org) features works of exceptional significance that further our understanding of living systems at all scales through the application of computational methods. All works published in PLoS Computational Biology are open access. Everything is immediately available subject only to the condition that the original authorship and source are properly attributed. Copyright is retained by the authors. The Public Library of Science uses the Creative Commons Attribution License.
About the Public Library of Science
The Public Library of Science (PLoS) is a non-profit organization of scientists and physicians committed to making the world's scientific and medical literature a freely available public resource. For more information, visit http://www.plos.org.
More information about the RadSafe