Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

An experimental Alzheimer's drug reverses genetic changes thought to spur the disease

04.05.2016

Aging takes its toll on the brain, and the cells of the hippocampus--a brain region with circuitry crucial to learning and memory--are particularly vulnerable to changes that can lead to Alzheimer's disease or cognitive decline. With the hope of counteracting the changes that can lead to these two conditions, researchers at Rockefeller University and their colleagues have begun examining the effects of a drug known to affect this circuitry.

In new research described recently in Molecular Psychiatry, a team led by Ana Pereira, Instructor in Clinical Medicine in Bruce McEwen's laboratory found that the drug, riluzole, is capable of reversing key genetic changes associated with these conditions.


After treatment with riluzole, the brains of old rats showed more of a transporter molecule that removes excess glutamate, (green fluorescence, right) as compared to untreated rats (left).

Credit: Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at The Rockefeller University/Molecular Psychiatry

"In aging and Alzheimer's, the chemical signal glutamate can accumulate between neurons, damaging the circuitry," Pereira says. "When we treated rats with riluzole, we saw a suite of changes. Perhaps most significantly, expression of molecules responsible for clearing excess glutamate returned to more youthful levels."

Previous work in McEwen's lab by Pereira has shown that the drug prompted structural changes in rats' neurons that prevent the memory loss often seen in old animals. Pereira is currently testing riluzole for the first time in Alzheimer's patients in a clinical trial at the Rockefeller University Hospital.

Glutamate clean up

Generally, glutamate is released to excite other neurons and doesn't linger in the spaces between them. As we age, though, the system gets a little leaky and glutamate can build up in these intercellular spaces.

This happens in part when neurons make less and less of the transporter molecule responsible for removing excess glutamate. When it accumulates, this essential neurotransmitter can cause big problems, damaging or killing neurons and so contributing to Alzheimer's disease, and other disorders.

Pereira and co-first author Jason Gray, a postdoc in the lab sought to better understand the molecular vulnerabilities of an aging glutamate system and riluzole's effect on it.

"The essence is we used a drug known to modulate glutamate, and when we gave it to old rats, we saw it reversed many of the changes that begin in middle age in the hippocampus," Gray says. "We saw a similar pattern when we compared the riluzole-induced changes to data from Alzheimer's patients--in a number of key pathways in the hippocampus, the drug produced an effect opposing that of the disease."

The drug, it turns out, modifies the activity of certain genes in an aged animal to resemble that of a younger rat. For example, the researchers found that the expression of a gene called EAAT2, which has been linked to Alzheimer's and is known to play a role in removing excess glutamate from nerve fibers, declines as the animals age. However, in rats treated with riluzole this gene's activity was brought back to its youthful levels.

New targets for treatments?

In addition to its potential ability to allay memory loss and cognitive decline, riluzole is attractive as a potential treatment for Alzheimer's. The drug is already being used to treat another neurological disease, amyotrophic lateral sclerosis, and is therefore considered relatively safe. In Pereira's ongoing clinical trial, patients with Alzheimer's disease have thus far been treated with either the drug or a placebo, and have been undergoing tests to help determine whether their brain functions have been improved.

"We hope to use a medication to break the cycle of toxicity by which glutamate can damage the neurons that use it as a neurotransmitter, and our studies so far suggest that riluzole may be able to accomplish this," Pereira says. "We found that in addition to recovering the expression of EAAT2, the drug restored genes critical for neural communication and plasticity, both of which decline with aging and even more significantly in Alzheimer's disease."

The findings also help to lay the groundwork for further study of glutamate transporters as potential targets for treating both conditions.

Media Contact

Katherine Fenz
kfenz@rockefeller.edu
212-327-7913

 @rockefelleruniv

http://www.rockefeller.edu 

Katherine Fenz | EurekAlert!

Further reports about: genes genetic changes glutamate memory loss neurons riluzole

More articles from Health and Medicine:

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

nachricht Flexible sensors can detect movement in GI tract
11.10.2017 | Massachusetts Institute of Technology

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>