Featured Research

from universities, journals, and other organizations

New Protein Found In Excessive Quantities In Alzheimer's Disease

Date:
December 16, 1997
Source:
Massachusetts General Hospital
Summary:
A research team based at the Massachusetts General Hospital has discovered a new gene that appears to play a role in Alzheimer's disease. The gene's protein is found in excessive quantities in brain tissue and cerebrospinal fluid of people with Alzheimer's and produces Alzheimer's-like damage in nerve cells.

A research team based at the Massachusetts General Hospital (MGH) has discovered a new gene that appears to play a role in Alzheimer's disease. The gene produces a protein in nerve cells, and the researchers found excessive quantities of this protein in brain tissue and cerebrospinal fluid (CSF) of people with Alzheimer's. They also showed that accumulation in nerve cells of this protein, called AD7c-NTP, causes changes similar to those seen in Alzheimer's, including cell death. Published in the December issue of the Journal of Clinical Investigation, the study additionally describes a highly sensitive and specific assay for AD7c-NTP, developed by scientists from the Nymox Corporation.

"There are many questions about the role this protein may actually play in Alzheimer's, but we're very excited about how closely its effects mimic the damage seen in Alzheimer's and how consistently excessive levels are seen in people with this terrible disease," says Suzanne de la Monte, MD, the MGH neuropathologist who is the paper's first author.

Alzheimer's is the most common cause of dementia in the Western hemisphere and currently affects more than 4 million Americans. In a small proportion of cases — 5 to 10 percent — the disease runs in families. Three genes have been discovered that cause familial Alzheimer's, and MGH researchers contributed to the discovery of all three genes. In most instances, however, Alzheimer's appears in people without a family history of the disease. The current study focuses on this common sporadic form of Alzheimer's.

De la Monte isolated the gene for AD7c-NTP and determined its sequence of nucleotides, the genetic building blocks that define a specific protein. She then showed that the gene's protein was produced in brain tissue but not in tissues from numerous other organs and that significantly higher levels of the protein were seen in tissue samples from people with Alzheimer's compared with samples from elderly people with no neurological disorder. In addition, elevated AD7c-NTP was seen much earlier in the course of the disease than several other proteins associated with Alzheimer's are known to appear. When the gene was introduced into cultured nerve cells and its protein was expressed, the cells grew abnormally long branches or processes and died, a phenomenon seen in Alzheimer's.

The researchers from Nymox, led by Hossein Ghanbari, PhD, developed a very sensitive test to measure levels of the protein in cerebrospinal fluid. They then examined samples from people who had died with Alzheimer's (confirmed by postmortem examination), who had early Alzheimer's, who had other neurologic diseases (multiple sclerosis or Parkinson's disease), or who had no neurologic disorders. The Nymox researchers, who did not know beforehand which diagnostic categories individual samples represented, found elevated AD7c-NTP levels in 84 percent of the confirmed Alzheimer's cases. Levels that could be considered elevated also were seen in 89 percent of the early Alzheimer's cases, compared with 11 percent of elderly individuals with no neurologic disease. In those with other neurologic disorders, levels were slightly higher than those seen in healthy controls.

"AD7c-NTP levels were uniquely elevated in patients with Alzheimer's," Ghanbari says. "We were particularly surprised to see this protein was present in very early Alzheimer's cases and that its level generally increased as patients got worse."

The researchers stress that they do not yet know whether the gene itself is abnormal or whether it is a normal gene that is overactivated by some other factor. However, nerve cells stimulated to produce AD7c-NTP can be used to screen possible Alzheimer's drugs for effectiveness. The protein assay could be helpful in determining whether an individual with dementia has Alzheimer's or another condition as well as for tracking the success of clinical Alzheimer's therapies.

Additional coauthors of the study are senior author Jack R. Wands, MD, of the MGH; Kasra Ghanbari, Iraj Beheshti, PhD, and Paul Averback, MD, of Nymox; William Frey, PhD, of the Ramsey Alzheimer's Treatment and Research Center in St. Paul, Minn.; and Stephen Hauser, MD, of the University of California Medical Center in San Francisco. The research was supported by grants from the National Institutes of Health, the American Cancer Society, Nymox Corporation and the Tan Yan Lee Foundation.


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. "New Protein Found In Excessive Quantities In Alzheimer's Disease." ScienceDaily. ScienceDaily, 16 December 1997. <www.sciencedaily.com/releases/1997/12/971216045921.htm>.
Massachusetts General Hospital. (1997, December 16). New Protein Found In Excessive Quantities In Alzheimer's Disease. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/1997/12/971216045921.htm
Massachusetts General Hospital. "New Protein Found In Excessive Quantities In Alzheimer's Disease." ScienceDaily. www.sciencedaily.com/releases/1997/12/971216045921.htm (accessed October 22, 2014).

Share This



More Health & Medicine News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

CDC Revamps Ebola Guidelines After Criticism

CDC Revamps Ebola Guidelines After Criticism

Newsy (Oct. 21, 2014) The Centers for Disease Control and Prevention have issued new protocols for healthcare workers interacting with Ebola patients. Video provided by Newsy
Powered by NewsLook.com
WHO: Ebola Vaccine Trials to Start a in January

WHO: Ebola Vaccine Trials to Start a in January

AP (Oct. 21, 2014) Tens of thousands of doses of experimental Ebola vaccines could be available for "real-world" testing in West Africa as soon as January as long as they are deemed safe in soon to start trials, the World Health Organization said Tuesday. (Oct. 21) Video provided by AP
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
CDC Issues New Ebola Guidelines for Health Workers

CDC Issues New Ebola Guidelines for Health Workers

Reuters - US Online Video (Oct. 21, 2014) The U.S. Centers for Disease Control and Prevention has set up new guidelines for health workers taking care of patients infected with Ebola. Linda So reports. Video provided by Reuters
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