Featured Research

from universities, journals, and other organizations

New culprit in Alzheimer’s disease: Too many blood vessels

Date:
September 1, 2011
Source:
University of British Columbia
Summary:
Scientists may have uncovered a new explanation for how Alzheimer's disease destroys the brain -- a profusion of blood vessels. They suggest that the growth of capillaries leads to a breakdown of the blood-brain barrier, allowing amyloid beta, the hallmark of the neurodegenerative disease, to be deposited in the brain tissue.

University of British Columbia scientists may have uncovered a new explanation for how Alzheimer's disease destroys the brain -- a profusion of blood vessels.

While the death of cells, whether they are in the walls of blood vessels or in brain tissue, has been a major focus of Alzheimer's disease research, a team led by Wilfred Jefferies, a professor in UBC's Michael Smith Laboratories, has shown that the neurodegenerative disease might in fact be caused by the propagation of cells in blood vessel walls.

Examining brain tissue from mouse models of Alzheimer's disease, Jefferies' team found nearly double the density of capillaries compared to normal mice. They also found a similarly higher density of capillaries in brain samples of people who had died of the disease, compared to samples from people who didn't have it.

Jefferies, in an article published online August 31 by PLoS One, theorizes that the profusion of blood vessels is stimulated by amyloid beta, a protein fragment that has become a hallmark of Alzheimer's disease. The blood vessel growth, or "neo-angiogenesis," leads to a breakdown of the blood-brain barrier -- the tightly interlocked network of cells that allows oxygen-carrying blood to reach brain tissue while blocking harmful substances, such as viruses.

"When the blood vessels grow, the cells of the vessel walls propagate by dividing," Jefferies says. "In the process of splitting into two new cells, they become temporarily rounded in shape, and that undermines the integrity of the blood-brain barrier, potentially allowing harmful elements from outside the brain to seep in."

The deterioration of the barrier might in turn allow the depositing of amyloid beta, which accumulates around neurons and eventually kills them.

Previous research had touched on the "leakiness" of the barrier, but it was assumed that it was caused by the death of blood vessels -- not their growth.

Jefferies also sees an intriguing parallel with the "wet" form of age-related macular degeneration, in which blood vessels grow behind the retina and then leak blood and fluid, leading to hemorrhaging, swelling, and formation of scar tissue.

"Given the new link between both conditions, the next logical step in the treatment of Alzheimer's disease would be to look for treatments that specifically target blood vessel growth," says Jefferies, who holds appointments in the departments of microbiology and immunology, medical genetics and zoology, and is also a member of the Biomedical Research Centre and the Brain Research Centre.

Jefferies collaborated with Dara Dickstein, a professor in the department of neuroscience at the Mount Sinai School of Medicine, New York. The team at UBC included graduate student Kaan Biron and technician Rayshad Gopaul.

The research was supported by grants from the Canadian Stroke Network and the Canadian Institutes of Health Research.


Story Source:

The above story is based on materials provided by University of British Columbia. Note: Materials may be edited for content and length.


Journal Reference:

  1. Biron KE, Dickstein DL, Gopaul R, Jefferies WA. Amyloid Triggers Extensive Cerebral Angiogenesis Causing Blood Brain Barrier Permeability and Hypervascularity in Alzheimer's Disease. PLoS ONE, 6(8): e23789 DOI: 10.1371/journal.pone.0023789

Cite This Page:

University of British Columbia. "New culprit in Alzheimer’s disease: Too many blood vessels." ScienceDaily. ScienceDaily, 1 September 2011. <www.sciencedaily.com/releases/2011/08/110831210054.htm>.
University of British Columbia. (2011, September 1). New culprit in Alzheimer’s disease: Too many blood vessels. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2011/08/110831210054.htm
University of British Columbia. "New culprit in Alzheimer’s disease: Too many blood vessels." ScienceDaily. www.sciencedaily.com/releases/2011/08/110831210054.htm (accessed October 2, 2014).

Share This



More Mind & Brain News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pregnancy Spacing Could Have Big Impact On Autism Risks

Pregnancy Spacing Could Have Big Impact On Autism Risks

Newsy (Oct. 1, 2014) A new study says children born less than one year and more than five years after a sibling can have an increased risk for autism. Video provided by Newsy
Powered by NewsLook.com
Stopping School Violence

Stopping School Violence

Ivanhoe (Oct. 1, 2014) A trauma doctor steps out of the hospital and into the classroom to teach kids how to calmly solve conflicts, avoiding a trip to the ER. Video provided by Ivanhoe
Powered by NewsLook.com
Pineal Cysts: Debilitating Pain

Pineal Cysts: Debilitating Pain

Ivanhoe (Oct. 1, 2014) A tiny cyst in the brain that can cause debilitating symptoms like chronic headaches and insomnia, and the doctor who performs the delicate surgery to remove them. Video provided by Ivanhoe
Powered by NewsLook.com
Burning Away Brain Tumors

Burning Away Brain Tumors

Ivanhoe (Oct. 1, 2014) Doctors are 'cooking' brain tumors. Hear how this new laser-heat procedure cuts down on recovery time. Video provided by Ivanhoe
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