Featured Research

from universities, journals, and other organizations

New target for Alzheimer's drugs

Date:
February 9, 2012
Source:
University of California - Riverside
Summary:
UC Riverside biomedical scientists have identified a new link between a protein (beta-arrestin) and short-term memory that could open new doors for the therapeutic treatment of neurological disorders, particularly Alzheimer's disease. They show that if beta-arrestin is removed from neurons, short-term memory loss is prevented. But beta-arrestin is also required for normal learning/memory. The researchers argue that a fine balance needs to be established, one that could be achieved by pharmaceutical drugs in the future.

Biomedical scientists at the University of California, Riverside have identified a new link between a protein called beta-arrestin and short-term memory that could open new doors for the therapeutic treatment of neurological disorders, particularly Alzheimer's disease.

Beta-arrestin is expressed in various cells of the body, including cells of the hippocampus, the region of the brain that is involved in learning and the formation of short-term memories. Beta-arrestin, the absence of which impairs normal learning in mice, is one of many "scaffolding proteins" -- proteins that support the connections between neurons in the brain.

As our brain develops, new connections called synapses are formed between neurons. In the hippocampus, the formation of synapses is a continuous process. As we learn something new, new connections are formed and some old ones become stronger through a process known as long-term potentiation (LTP). But because brains have only a limited capacity, other old connections must disassemble through a process known as long-term depression (LTD) in order for new synapses to form.

The researchers report online last week in the Proceedings of the National Academy of Sciences that beta-arrestin plays an important role in the plasticity of synaptic connections and LTD by regulating the "actin cytoskeleton," a dynamic filamentous network of proteins that forms the "backbone" of neurons and is involved in forming new and disassembling old synaptic connections.

"In some pathological conditions such as Alzheimer's disease, loss of the old synaptic connections far exceeds the formation of new ones, resulting in overall loss of synapses and short-term memory loss," said Iryna M. Ethell, an associate professor of biomedical sciences and the lead author of the research paper. "Our work, done on mice, shows that if beta-arrestin is removed from neurons, this loss of synapses is prevented. But we also know that beta-arrestin is required for normal learning and memory; so a fine balance needs to be established. This balance could be easily achieved by pharmaceutical drugs in the future."

This is the first time researchers anywhere have linked beta-arrestin to Alzheimer's and learning/memory.

Ethell explained that beta-arrestin can be visualized as energy supplied to a puppeteer (actin cytoskeleton) controlling the strings of the puppets (inter-neuronal connections). For normal learning to take place, the puppeteer needs to move the strings in a specific order. But in patients with Alzheimer's, this supply of energy over-activates and the strings are pulled in a disorderly fashion that results in the strings being broken (loss of synapses) and the puppets collapsing. While the removal of beta-arrestin would prevent this collapse, a complete loss of beta-arrestin would mean no movement of the puppets at all (that is, no learning in the brain), which is equally undesirable.

"A selective tuning of beta-arrestin activity is therefore necessary to partially reduce synapse disassembly," said Crystal G. Pontrello, the first author of the research paper and a postdoctoral researcher in Ethell's lab. "What you want, ideally, is the elimination of only some unused old synaptic connections so that there is room to make new connections."

Ethell and Pontrello were joined in the research by UC Riverside's Min-Yu Sun, Alice Lin, Todd A. Fiacco and Kathryn A. DeFea.

The research was supported by a grant to Ethell by the National Institutes of Health.


Story Source:

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


Journal Reference:

  1. C. G. Pontrello, M.-Y. Sun, A. Lin, T. A. Fiacco, K. A. DeFea, I. M. Ethell. PNAS Plus: Cofilin under control of -arrestin-2 in NMDA-dependent dendritic spine plasticity, long-term depression (LTD), and learning. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1118803109

Cite This Page:

University of California - Riverside. "New target for Alzheimer's drugs." ScienceDaily. ScienceDaily, 9 February 2012. <www.sciencedaily.com/releases/2012/02/120209101839.htm>.
University of California - Riverside. (2012, February 9). New target for Alzheimer's drugs. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2012/02/120209101839.htm
University of California - Riverside. "New target for Alzheimer's drugs." ScienceDaily. www.sciencedaily.com/releases/2012/02/120209101839.htm (accessed April 20, 2014).

Share This



More Mind & Brain News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Study On Artists' Brain Shows They're 'Structurally Unique'

Study On Artists' Brain Shows They're 'Structurally Unique'

Newsy (Apr. 17, 2014) The brains of artists aren't really left-brain or right-brain, but rather have extra neural matter in visual and motor control areas. Video provided by Newsy
Powered by NewsLook.com
Is Apathy A Sign Of A Shrinking Brain?

Is Apathy A Sign Of A Shrinking Brain?

Newsy (Apr. 17, 2014) A recent study links apathetic feelings to a smaller brain. Researchers say the results indicate a need for apathy screening for at-risk seniors. Video provided by Newsy
Powered by NewsLook.com
Are School Dress Codes Too Strict?

Are School Dress Codes Too Strict?

AP (Apr. 16, 2014) Pushing the limits on style and self-expression is a rite of passage for teens and even younger kids. How far should schools go with their dress codes? The courts have sided with schools in an era when school safety is paramount. (April 16) Video provided by AP
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. 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:
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