Featured Research

from universities, journals, and other organizations

Rheumatoid arthritis signaling protein reverses Alzheimer's disease in mouse model

Date:
August 23, 2010
Source:
University of South Florida (USF Health)
Summary:
A new study looks at what effect innate immunity gone bad in rheumatoid arthritis may play in protecting against Alzheimer's disease. Researchers found a signaling protein for RA reversed Alzheimer's in a mouse model.

Huntington Potter, professor at the USF Health Byrd Alzheimer's Institute, University of South Florida, was principal investigator for the study.
Credit: ฉ University of South Florida

A signaling protein released during rheumatoid arthritis dramatically reduced Alzheimer's disease pathology and reversed the memory impairment of mice bred to develop symptoms of the neurodegenerative disease, a new study by the University of South Florida reports. Researchers found that the protein, GM-CSF, likely stimulates the body's natural scavenger cells to attack and remove Alzheimer's amyloid deposits in the brain.

The study appears online in the Journal of Alzheimer's Disease.

People with rheumatoid arthritis, a chronic disease leading to inflammation of joints and surrounding tissue, are less likely than those without arthritis to develop Alzheimer's. While it was commonly assumed that non-steroidal anti-inflammatory drugs may help prevent onset and progression of Alzheimer's disease, recent NSAID clinical trials proved unsuccessful for patients with Alzheimer's.

The USF researchers are among the first to look at what effect innate immunity gone awry in rheumatoid arthritis may play in protecting against Alzheimer's disease.

"Our findings provide a compelling explanation for why rheumatoid arthritis is a negative risk factor for Alzheimer's disease," said principal investigator Huntington Potter, PhD, professor of molecular medicine at the USF Health Byrd Alzheimer's Institute and director of the Florida Alzheimer's Disease Research Center.

"Moreover, the recombinant human form of GM-CSF (Leukineฎ) is already approved by the FDA and has been used for years to treat certain cancer patients who need to generate more immune cells," Dr. Potter said. "Our study, along with the drug's track record for safety, suggests Leukine should be tested in humans as a potential treatment for Alzheimer's disease."

The researchers analyzed three rheumatoid arthritis growth factors in mouse models and identified the signaling protein GM-CSF as the most promising for potential protective benefit against Alzheimer's disease. Then, they peripherally injected GM-CSF into two groups of mice -- those genetically altered to develop memory problems mimicking Alzheimer's disease and normal, aged mice. Behavioral tests confirmed the Alzheimer's mice were exhibiting signs of memory impairment at age 12 months. Another two control groups of mice -- the Alzheimer's mice and normal mice -- were administered saline (placebo).

After the 10th day of injections, all the mice began a series of behavioral testing. At the end of the 20-day study, the cognitively impaired mice treated with GM-CSF performed substantially better on tests measuring their working memory and learning. In fact, their memories were similar to normal aged mice without dementia. Even the normal mice treated with GM-CSF performed slightly better than their untreated peers. The Alzheimer's mice administered saline continued to do poorly on the tests.

"We were pretty amazed that the treatment completely reversed cognitive impairment in 20 days," said Tim Boyd, PhD, who, together with Steven Bennett, PhD, is a study lead author.

In addition, the brains of GM-CSF-treated Alzheimer's mice showed more than a 50-percent decrease in beta amyloid, a substance forming the sticky clumps of plaques that are a hallmark of Alzheimer's disease. This reduction in Alzheimer's plaques and associated restoration of memory was accompanied by more immune cells known as microglia in the brain. Microglia are like the body's natural garbage collection cells that rush to damaged or inflamed areas to get rid of toxic substances.

The researchers suggest that GM-CSF boosted during the immune system overdrive of rheumatoid arthritis helps harness the beneficial properties of inflammation in the brain. The protein may do this by recruiting more microglia from the peripheral blood into the brain to remove Alzheimer's plaques, Dr. Potter said. An apparent increase in neural cell connections in the brains of the GM-CSF-treated mice may also help explain GM-CSF's association with improving memory decline in Alzheimer's disease, the researchers said.

The USF Health Byrd Alzheimer's Institute plans to begin a pilot clinical trial later this year investigating GM-CSF (Leukine) in patients with mild or moderate Alzheimer's disease.


Story Source:

The above story is based on materials provided by University of South Florida (USF Health). Note: Materials may be edited for content and length.


Journal Reference:

  1. Tim D. Boyd, Steven P. Bennett, Takashi Mori, Nikolas Governatori, Melissa Runfeldt, Michelle Norden; Jaya Padmanabhan, Peter Neame, Inge Wefes, Juan Sanchez-Ramos, Gary W. Arendash, Huntington Potter. GM-CSF up-regulated in reumatoid arthritis reverses cognitive impairment and amyloidosis in Alzheimer mice. Alzheimer's and Dementia, 2010; 6 (4): S575 DOI: 10.1016/j.jalz.2010.05.1962

Cite This Page:

University of South Florida (USF Health). "Rheumatoid arthritis signaling protein reverses Alzheimer's disease in mouse model." ScienceDaily. ScienceDaily, 23 August 2010. <www.sciencedaily.com/releases/2010/08/100822211549.htm>.
University of South Florida (USF Health). (2010, August 23). Rheumatoid arthritis signaling protein reverses Alzheimer's disease in mouse model. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2010/08/100822211549.htm
University of South Florida (USF Health). "Rheumatoid arthritis signaling protein reverses Alzheimer's disease in mouse model." ScienceDaily. www.sciencedaily.com/releases/2010/08/100822211549.htm (accessed July 22, 2014).

Share This




More Health & Medicine News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) — Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) — The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Scientists Find New Way To Make Human Platelets

Scientists Find New Way To Make Human Platelets

Newsy (July 22, 2014) — Boston scientists have discovered a new way to create fully functioning human platelets using a bioreactor and human stem cells. Video provided by Newsy
Powered by NewsLook.com
Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) — New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
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:
from the past week

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