Featured Research

from universities, journals, and other organizations

Alzheimer's-associated Plaques Can Form In A Day, And Alzheimer's Symptoms Soon Follow

Date:
February 8, 2008
Source:
Massachusetts General Hospital
Summary:
The amyloid plaques found in the brains of Alzheimer's disease patients may form much more rapidly than previously expected. Using an advanced microscopic imaging technique to examine brain tissue in mouse models of the devastating neurological disorder, researchers find that plaques can develop in as little as a day and that Alzheimer's-associated neuronal changes appear soon afterwards.

The amyloid plaques found in the brains of Alzheimer's disease patients may form much more rapidly than previously expected.
Credit: iStockphoto/Carme Balcells

The amyloid plaques found in the brains of Alzheimer's disease patients may form much more rapidly than previously expected. Using an advanced microscopic imaging technique to examine brain tissue in mouse models of the devastating neurological disorder, researchers from the MassGeneral Institute for Neurodegenerative Disease (MGH-MIND), working with colleagues from Washington University School of Medicine, find that plaques can develop in as little as a day and that Alzheimer's-associated neuronal changes appear soon afterwards.

Related Articles


"While we've known for a long time what amyloid plaques and other changes seen in the brains of Alzheimer's patients look like, we didn't know in what order and at what speed those changes occur," says Bradley Hyman, MD, PhD, director of the Alzheimer's Unit at MGH-MIND and senior author of the Nature paper.* "Understanding the rules that govern plaque formation may lead us to ideas about how to intervene in the process."

To investigate the timing of these brain changes, the researchers used a novel technique for microscopically imaging the brains of living animals. Using several strains of transgenic mice destined to develop amyloid plaques, they imaged initially plaque-free areas of the brain on a regular basis -- first weekly and, in subsequent experiments, daily.

Although plaques formed rarely, they could appear as little as 24 hours after a previous plaque-free image was taken. The new plaques were similar in appearance to those seen in the brains of Alzheimer's patients and in the mouse models, and subsequent imaging showed little change in the size of plaques once they had formed.

Earlier investigations have shown that levels of microglia -- neuronal support cells that react to inflammation and other damage -- rise in the vicinity of amyloid plaques. Imaging an Alzheimer's mouse model that expresses a fluorescent marker in microglia showed that the cells were attracted to new plaques within a day of formation. Although there was no evidence that microglia were actively removing the plaques, the investigators hypothesize that they may help restrict further plaque growth. Examining neurons adjacent to plaques showed that the kind of changes associated with Alzheimer's -- distortions in the projections through which neuronal signals pass -- appear rapidly and approach maximum effect within five days.

"These results confirm the suspicion we've had that plaques are a primary event in the glial and neuronal changes that underlie Alzheimer's dementia," Hyman says. "We hope that what we've learned about the time frame and sequence of events will help us find ways to keep plaques from forming." Hyman is the John Penny Professor of Neurology at Harvard Medical School.

*This research is reported in the Feb. 7 issue of Nature.

Melanie Meyer-Luehmann, PhD, of MGH-MIND is the first author of the Nature report; Washington University School of Medicine co-authors Jessica Koenigsknecht-Talboo, PhD, and David Holtzman, MD, provided the transgenic mice and collaborated on the microglial experients. Aditional co-authors are Tara Spires-Jones, Claudia Prada, MD, Monica Garcia-Alloza, Alix de Calignon, Anete Rozkalne, and Brian Bacskai, PhD, all of MGH-MIND. The study was supported by grants from the National Institutes of Health and the Alzheimer's Association.


Story Source:

The above story is based on materials provided by Massachusetts General Hospital. Note: Materials may be edited for content and length.


Cite This Page:

Massachusetts General Hospital. "Alzheimer's-associated Plaques Can Form In A Day, And Alzheimer's Symptoms Soon Follow." ScienceDaily. ScienceDaily, 8 February 2008. <www.sciencedaily.com/releases/2008/02/080206131646.htm>.
Massachusetts General Hospital. (2008, February 8). Alzheimer's-associated Plaques Can Form In A Day, And Alzheimer's Symptoms Soon Follow. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2008/02/080206131646.htm
Massachusetts General Hospital. "Alzheimer's-associated Plaques Can Form In A Day, And Alzheimer's Symptoms Soon Follow." ScienceDaily. www.sciencedaily.com/releases/2008/02/080206131646.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Touch-Free Smart Phone Empowers Mobility-Impaired

Touch-Free Smart Phone Empowers Mobility-Impaired

Reuters - Innovations Video Online (Dec. 21, 2014) A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Reuters - Innovations Video Online (Dec. 21, 2014) A team of scientists led by Danish chemist Jorn Christensen says they have isolated two chemical compounds within an existing antipsychotic medication that could be used to help a range of failing antibiotics work against killer bacterial infections, such as Tuberculosis. Jim Drury went to meet him. Video provided by Reuters
Powered by NewsLook.com
Hugging It Out Could Help You Ward Off A Cold

Hugging It Out Could Help You Ward Off A Cold

Newsy (Dec. 21, 2014) Carnegie Mellon researchers found frequent hugs can help people avoid stress-related illnesses. Video provided by Newsy
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