Featured Research

from universities, journals, and other organizations

Study Links Viruses And Vascular Diseases

Date:
March 5, 1998
Source:
Washington University In St. Louis
Summary:
Most people know that cigarettes and high-fat food can contribute to atherosclerosis, the leading killer in the developed world. But is an unhealthy lifestyle all it takes to clog arteries? A small but vocal group of researchers believes atherosclerosis starts with a virus, not a cheeseburger.

by Chris Woolston

Related Articles


Most people know that cigarettes and high-fat food can contribute to atherosclerosis, the leading killer in the developed world. But is an unhealthy lifestyle all it takes to clog arteries? A small but vocal group of researchers believes atherosclerosis starts with a virus, not a cheeseburger. According to the theory, vascular damage caused by a virus could lay a foundation for the build-up of plaque.

Though it has its supporters, this theory has always suffered a credibility problem -- there has never been any direct evidence that viruses can injure human vessels. Now, thanks to a surprising discovery at Washington University School of Medicine in St. Louis, there is a new reason to reconsider the idea. In a recent issue of Nature Medicine, the researchers reported that a virus related to those that cause mononucleosis and Kaposi's sarcoma can injure arteries in mice, the first time such an effect had been seen in mammals. The study was supported by Monsanto-Searle, the National Institutes of Health and the National Cancer Institute.

"We're still a long way from showing that viruses can trigger atherosclerosis or other vascular diseases in humans," says senior author Herbert W. Virgin, M.D., Ph.D., an assistant professor of pathology, molecular microbiology and medicine. "But now we have a better idea that it may be possible, and we know which viruses might be involved."

The discovery at the School of Medicine echoes recent studies that suggest a link between bacterial infections and some vascular diseases. That link is still inconclusive, but Virgin believes it's entirely possible that both viruses and bacteria might be capable of damaging blood vessels and triggering disease. "It's highly unlikely that one single agent is the cause of all vascular disease," he says.

If viruses do in fact set the stage for atherosclerosis, physicians may someday be able to prevent the disease with a vaccine, Virgin says. But even if that's theoretically possible, such a vaccine lies far in the future, he adds. For now, viruses may be unavoidable, but people can still prevent atherosclerosis by staying away from high-fat food and cigarettes, Virgin explains. "At most, viruses could initiate only the earliest stages of the disease," he says. "They certainly couldn't block arteries on their own."

Damage resembles human diseases

Normal mice never develop full-blown atherosclerosis, which makes them imperfect models, Virgin says. Nevertheless, he and his colleagues found lesions that somewhat resembled the early stages of the disease. As with atherosclerosis, the damage was limited to the major arteries. Most importantly, the injured portions began to accumulate fatty plaque.

The vascular injuries also closely mimicked a group of human vascular diseases -- Taskayasu's arteritis, temporal arteritis and Kawasaki's disease -- whose origins have always been a mystery. The early stages of these diseases are marked by rashes and fever, symptoms typical of viral infection. "If it turns out that viruses cause these diseases in humans, few physicians would be surprised," says co-researcher Samuel H. Speck, Ph.D., an associate professor of pathology and molecular microbiology. "The link between viruses and atherosclerosis is much more controversial."

Intriguingly, infections in newborn mice led to fatal vascular disease when the animals were well into adulthood. "The infection doesn't cause vascular disease immediately, but it seems to set the whole process in motion," Virgin says. "This may suggest a model for how atherosclerosis and other vascular diseases progress in humans." The virus had little effect on healthy adult mice but did cause severe vascular disease in adult mice with compromised immune systems. At first, Virgin, Speck and colleagues had no intention of studying vascular disease; they fully expected the mouse virus to cause cancer. "The virus had been associated with lymphoma, but nobody had any idea it could damage arteries," Speck says. "When we dissected infected mice and saw the damage, we were quite surprised."

Viruses under suspicion

The virus used in the study is found only in mice, but it's closely related to the Epstein-Barr virus that causes mononucleosis in humans. About 75 percent of people over 30 carry this virus, Speck says. Another family member is thought to cause Kaposi's sarcoma, a cancer most commonly seen in AIDS patients. The extremely common herpesvirus simplex 1, the cause of cold sores, is a more distant relative. "These viruses are now legitimate candidates for initiating human vascular disease," Virgin says. "It's a possibility that deserves further investigation."

Despite repeated efforts, researchers have never been able to prove or disprove the hypothesis that viruses trigger human vascular disease. A middle-aged person with atherosclerosis will have been exposed to hundreds of viruses, making it very difficult to link the vascular disease to a particular infection, Virgin says. Until someone catches a virus in the act of damaging a human artery, most researchers will remain skeptical that it can ever happen. Knowing which viruses to look for will aid the search tremendously, he says.

###

Note: For more information, refer to K.E. Weck, et.al., "Murine g-herpesvirus 68 causes Severe Large- vessel Arteritis in Mice Lacking Interferon-g Responsiveness: A New Model for Virus-induced Vascular Disease," Nature Medicine, Vol. 3 (12) pp. 1346-1353, December 1997.0


Story Source:

The above story is based on materials provided by Washington University In St. Louis. Note: Materials may be edited for content and length.


Cite This Page:

Washington University In St. Louis. "Study Links Viruses And Vascular Diseases." ScienceDaily. ScienceDaily, 5 March 1998. <www.sciencedaily.com/releases/1998/03/980305054050.htm>.
Washington University In St. Louis. (1998, March 5). Study Links Viruses And Vascular Diseases. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/1998/03/980305054050.htm
Washington University In St. Louis. "Study Links Viruses And Vascular Diseases." ScienceDaily. www.sciencedaily.com/releases/1998/03/980305054050.htm (accessed October 25, 2014).

Share This



More Health & Medicine News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins