Featured Research

from universities, journals, and other organizations

How Antidepressants And Cocaine Interact With Brain Cell Targets

Date:
July 31, 2008
Source:
New York- Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College
Summary:
Scientists have now described the specifics of how brain cells process antidepressant drugs, cocaine and amphetamines. These novel findings could prove useful in the development of more targeted medication therapies for a host of psychiatric diseases, most notably in the area of addiction.

In a first, scientists from Weill Cornell Medical College and Columbia University Medical Center have described the specifics of how brain cells process antidepressant drugs, cocaine and amphetamines.

Related Articles


These novel findings could prove useful in the development of more targeted medication therapies for a host of psychiatric diseases, most notably in the area of addiction.

Their breakthrough research, featured as the cover story in a recent issue of Molecular Cell, describes the precise molecular and biochemical structure of drug targets known as neurotransmitter-sodium symporters (NSSs), and how cells use them to enable neural signaling in the brain. A second study, published in the latest issue of Nature Neuroscience, pinpoints where the drug molecules bind in the neurotransmitter transporter — their target in the human nervous system.

"These findings are so clear and detailed at the level of molecular behavior that they will be most valuable to developing more effective therapies for mood disorders and neurologic and psychiatric diseases, and to direct effective treatments for drug addiction to cocaine and amphetamines," says co-lead author Dr. Harel Weinstein, Chairman and Maxwell M. Upson Professor of Physiology and Biophysics, and director of the Institute for Computational Biomedicine at Weill Cornell Medical College. "This research may also open the door to the development of new therapies for dopamine-neurotransmitter disorders such as Parkinson's disease, schizophrenia, and anxiety and depression."

To make their observations, the research team led by Dr. Jonathan Javitch, senior author of the Molecular Cell study and contributing author to the Nature Neuroscience study, and professor of Psychiatry and Pharmacology in the Center for Molecular Recognition at Columbia University Medical Center, stabilized different structural states of the neurotransmitter-sodium-symporter molecule that relate to steps in its function. This allowed the team to study how substrates and inhibitors affect the transition between these different states, and thus to understand the way in which its function is accomplished.

"Crystallography had allowed the identification of only one structural form of the molecule, but our experiments and computations were able to identify how this form changes and thereby add an understanding of the functional role of the different forms that the molecule must adopt to accomplish transport activity," says Dr. Javitch.

The main surprise was the realization that two binding sites on the transporter molecule need to be filled simultaneously and cooperate in order for transport to be driven across the cell membrane. For these studies, the scientists used the crystal structure of a bacterial transporter that is very similar to human neurotransmitter transporters. They performed computer simulations to reveal the path of the transported molecules into cells. Laboratory experimentation was used to test the computational predictions and validate the researchers' inferences.

Together, these procedures revealed a finely-tuned process in which two sodium ions bind and stabilize the transporter molecule for the correct positioning of the two messenger molecules — one deep in the center of the protein, and the other closer to the entrance. Like a key engaging a lock mechanism, this second binding causes changes in the transporter throughout the structure, allowing one of the two sodium molecules to move inward, and then release the deeply bound messenger and its sodium partner into the cell.

In the bacterial transporter studied, antidepressant molecules bind in the outer one of two sites, and stop the transport mechanism, leaving the messenger molecule outside the cell.

The second team of researchers, involving a collaboration of the Weinstein and Javitch labs with colleagues in Denmark (the labs of Ulrik Gether and Claus Loland), found that in the human dopamine transporter cocaine binds in the deep site, unlike the antidepressant binding in the bacterial transporter. Therefore, the researchers conclude that anti-cocaine therapy will be more complicated, because interfering with cocaine binding also means interference with the binding of natural messengers.

"This finding might steer anti-cocaine therapy in a completely new direction," says Dr. Weinstein.

Molecular understanding at this level of structural and dynamic detail is rare in the world of drug development, the authors note. Only about 15 percent of all drugs have a known molecular method-of-action, even though the effects of these drugs within the body — after very stringent and controlled laboratory testing — are well understood pharmacologically.

Contributing authors to the Molecular Cell study include Dr. Lei Shi from Weill Cornell Medical College, who had a major role in the computational simulations; Dr. Matthias Quick from Columbia University Medical Center and the New York State Psychiatric Institute, who had a major role in the experimental component; and Dr. Yongfang Zhao from Columbia University Medical Center.

Lead authors of the Nature Neuroscience study are first author Dr. Thijs Beuming of Weill Cornell Medical College and senior authors Drs. Claus Loland and Ulrik Gether of The Panum Institute of the University of Copenhagen, Denmark. Additional co-authors include Drs. Julie Kniazeff, Marianne Bergmann and Klaudia Raniszewska of The Panum Institute of the University of Copenhagen; Drs. Lei Shi and Luis Gracia of Weill Cornell; and Dr. Amy Hauck Newman of the National Institute on Drug Abuse (NIDA).

The NIH supported these studies, and it is noteworthy that both the Molecular Cell and the Nature Neuroscience study share an NIH funding source, a Program Project grant awarded by the National Institute on Drug Abuse and directed by Dr. Weinstein, with Drs. Javitch and Gether each directing one of the projects. Additional support came from the Danish Medical Research Council, the Lundbeck Foundation, the Novo Nordisk Foundation and the Maersk Foundation — all in Europe.


Story Source:

The above story is based on materials provided by New York- Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College. Note: Materials may be edited for content and length.


Cite This Page:

New York- Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College. "How Antidepressants And Cocaine Interact With Brain Cell Targets." ScienceDaily. ScienceDaily, 31 July 2008. <www.sciencedaily.com/releases/2008/07/080729133515.htm>.
New York- Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College. (2008, July 31). How Antidepressants And Cocaine Interact With Brain Cell Targets. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2008/07/080729133515.htm
New York- Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College. "How Antidepressants And Cocaine Interact With Brain Cell Targets." ScienceDaily. www.sciencedaily.com/releases/2008/07/080729133515.htm (accessed October 30, 2014).

Share This



More Mind & Brain News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Techy Tots Are Forefront of London's Baby Show

Techy Tots Are Forefront of London's Baby Show

AP (Oct. 28, 2014) Moms and Dads get a more hands-on approach to parenting with tech-centric products for raising their little ones. (Oct. 28) Video provided by AP
Powered by NewsLook.com
Cocoa Could Be As Good For Memory As It Is For A Sweet Tooth

Cocoa Could Be As Good For Memory As It Is For A Sweet Tooth

Newsy (Oct. 27, 2014) Researchers have come up with another reason why dark chocolate is good for your health. A substance in the treat can reportedly help with memory. Video provided by Newsy
Powered by NewsLook.com
Five-Year-Olds Learn Coding as Britain Eyes Digital Future

Five-Year-Olds Learn Coding as Britain Eyes Digital Future

AFP (Oct. 27, 2014) Coding has become compulsory for children as young as five in schools across the UK. Making it the first major world economy to overhaul its IT teaching and put programming at its core. Duration: 02:19 Video provided by AFP
Powered by NewsLook.com
Academic Scandal Shocks UNC

Academic Scandal Shocks UNC

AP (Oct. 23, 2014) A scandal involving bogus classes and inflated grades at the University of North Carolina was bigger than previously reported, a new investigation found. (Oct. 23) Video provided by AP
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