Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Herpes research uncovers possible clue to Alzheimer’s disease

07.11.2003


Researchers at Brown University and the Marine Biological Laboratory at Woods Hole, Mass., have found a physical connection between the herpes simplex virus and amyloid precursor protein, a protein that breaks down to form a major component of the amyloid plaques that are consistently present in the brains of persons with Alzheimer’s disease.



Amyloid precursor protein – or APP – breaks down to form beta-amyloid. There is strong evidence, according to the researchers, that beta-amyloid is the underlying cause of Alzheimer’s.

While the scientists caution that no conclusions about Alzheimer’s can be drawn from their findings, Dr. Elaine Bearer, senior research scientist and associate professor in Brown’s Department of Pathology and Laboratory Medicine, believes the work does in fact link the common herpes virus of cold sores with the neurodegenerative disorder. Bearer is also a summer investigator at the Marine Biological Laboratory at Woods Hole, Mass.


Past studies have implicated the herpes virus in the onset of Alzheimer’s disease, but agreement within the scientific community on the value of that research is far from universal. Bearer expects that the discovery of a physical interaction between APP and the herpes virus will trigger further investigations into the role the virus may play in the disease, and even into possible uses of the virus in therapy.

The scientists stress that none of what they found should cause alarm among those who have at one time had a cold sore. According to Bearer, nearly 85 percent of us harbor the herpes simplex virus and most of us never develop Alzheimer’s.

The researchers discovered the interaction between the herpes simplex virus (HSV) and APP while conducting experiments in the giant axon of squid at the Marine Biological Laboratory. Prasanna Satpute-Krishnan and Joseph A. DeGiorgis, both doctoral candidates in Brown’s graduate program at the time of the research, were seeking to learn how viruses are carried around the body – within cells and from one cell to another. Specifically, they were examining how the herpes simplex virus travels back to the lip area to form a recurring blister after remaining latent for some time in the trigeminal ganglion, a collection of nerve cells next to the brain.

What they found was that the herpes virus was interacting with APP, a putative motor receptor that recruits a microtubular motor, kinesin, for transport through neurons. This was the first time scientists had observed any physical interaction between the herpes virus and APP.

Without the APP, the virus moves backward up an axon (a long extension of a neuron) from the area of the lip towards the trigeminal ganglion. But the Brown researchers discovered that once it interacts with the APP, the virus travels in the opposite direction – what scientists describe as anterograde transport – back down to the lip. The researchers also found that once coupled with the APP, the virus moves remarkably fast.

“It’s as if the virus hijacks a car – which in this case would be the kinesin – and the APP is the driver,” explains Bearer. “The virus takes the APP where it wants to be, not where the APP wants to be.”

The build-up of beta-amyloid (formed in the breakdown of APP) is found consistently in the brains of Alzheimer’s patients, and many scientists are now convinced it is involved in the disease, according to Satpute-Krishnan. Questions persist, however, as to what that involvement is, and why, when APP is found in all of us, it causes problems only in a few.

Perhaps, Bearer speculates, when the APP is co-opted by the herpes virus, the APP breaks down at a location where it would not normally appear – and at a very different rate. “When APP piles up around neurons, the neurons die,” she explains. “But we don’t yet know if this is a secondary or a primary cause of Alzheimer’s.”

“At this point, of course, we don’t yet know whether herpes plays a causal role in Alzheimer’s disease,” DeGiorgis notes. “But our research does provide some interesting new insight into both diseases.”

A paper outlining the findings of the Brown/MBL researchers – titled “Fast Anterograde Transport of Herpes Simplex Virus: Role of Amyloid Precursor Protein” – will appear in the December issue of Aging Cell, published by Blackwell Publishing in England and at the publisher’s “OnlineEarly” site [http://www.blackwell-synergy.com/links/toc/ace].

Satpute-Krishnan, the first author of the paper, is a graduate student in Brown’s Molecular Biology, Cell Biology and Biochemistry Graduate Program. Bearer, who holds both an M.D. and a Ph.D., is an experimental pathologist. DeGiorgis, who earned his Ph.D. in Bearer’s lab last year, is now with the National Institutes of Health.

Experiments in this study were conducted in the giant axon of squid, a model widely used in research because with a diameter of nearly a millimeter it is 1,000 times thicker than a human axon. Researchers are able to inject substances into the giant axon and then observe the behavior of those substances through high-powered microscopes.

“It is pretty extraordinary that breakthroughs in Alzheimer’s disease and in the pathogenesis of herpes virus should be made using the squid of the North Atlantic sea,” notes Bearer.

Last summer Brown University and the Marine Biological Laboratory formalized their alliance for teaching and research. The affiliation between the two institutions established the Brown-MBL Graduate Program in Biological and Environmental Sciences. In addition, it will promote faculty exchanges and research collaborations, such as the one conducted by Satpute-Krishnan, DeGiorgis and Bearer.

The affiliation between MBL and Brown takes advantage of the geographic proximity of the two institutions, uniting their faculty expertise in biology and medicine, particularly for molecular biology, genomics, ecosystems studies, environmental science, global infectious diseases, neuroscience and public health. Student recruitment for the Brown-MBL Graduate Program got under way this fall, with the first students expected to begin their studies next year.

MBL is an internationally known, independent, nonprofit institution dedicated to improving the human condition through creative research and education in the biological, biomedical and environmental sciences. Founded in 1888, the MBL is the oldest private marine laboratory in the Western Hemisphere.

Cynthia Ferguson | Brown University
Further information:
http://www.brown.edu/Administration/News_Bureau

More articles from Health and Medicine:

nachricht New study points the way to therapy for rare cancer that targets the young
22.11.2017 | Rockefeller University

nachricht Penn study identifies new malaria parasites in wild bonobos
21.11.2017 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>