News | January 23, 2007

New Method Holds Promise For Treating Brain Injuries

Jan. 24, 2007 - When brain cells die, whether from head trauma, stroke or disease, a substance called glutamate floods the surrounding areas, overloading the cells in its path and setting off a chain reaction that damages whole swathes of tissue. Glutamate is always present in the brain, where it carries nerve impulses across the gaps between cells. But when this chemical is released by damaged or dying brain cells, the result is a flood that overexcites nearby cells and kills them.

A new method for ridding the brain of excess glutamate has been developed at the Weizmann Institute of Science. This method takes a new approach to the problem, compared with previous attempts based on drugs that must enter the brain to prevent the deleterious action of glutamate. Many drugs, however, can't cross the blood-brain barrier into the brain, while other promising treatments have proved ineffective in clinical trials. Prof. Vivian Teichberg, of the Institute's Neurobiology Department, working together with Prof. Yoram Shapira and Dr. Alexander Zlotnik of the Soroka Medical Center and Ben Gurion University of the Negev, has shown that in rats, an enzyme in the blood can be activated to "mop up" toxic glutamate spills in the brain and prevent much of the damage. This method may soon be entering clinical trials to see if it can do the same for humans.

Though the brain has its own means of recycling glutamate, injury causes the system to malfunction, leading to glutamate build up. Dr. Teichberg reasoned that this problem could be circumvented by passing glutamate from the fluid surrounding brain cells into the bloodstream. But first, he had to have a clear understanding of the mechanism for moving glutamate from the brain to the blood. Glutamate concentrations are several times higher in the blood than in the brain, and the body must be able to pump the chemical "upstream."

Glutamate pumps, called transporters, are found on the outsides of blood vessels, on cells that come into contact with the brain. These collect glutamate, creating small zones of high concentration from which the glutamate can then be released into the bloodstream.

Basic chemistry told him that he could affect the transporter activity by tweaking glutamate levels in the blood. When blood levels are low, the greater difference in concentrations causes the brain to release more glutamate into the bloodstream. He uses an enzyme called GOT that is normally present in blood to bind glutamate chemically and inactivate it, effectively lowering levels in the blood and kicking transporter activity into high gear. In their experiments, Teichberg and his colleagues used this method to scavenge blood glutamate in rats with simulated traumatic brain injury. They found that glutamate cleared out of the animals' brains effectively, and damage was prevented.

Related Content

CDN to Integrate Advanced Cardiac Imaging Tools From DiA Imaging Analysis
Technology | Advanced Visualization | August 10, 2017
August 10, 2017 — CDN recently announced a new partnership agreement with DiA Imaging Analysis Ltd., makers of next-g
Fujifilm Launches Synapse PACS Version 5
Technology | PACS | August 03, 2017
August 3, 2017 – Fujifilm Medical Systems U.S.A. Inc.
Agfa Receives FDA 510(k) for Xtend Functionalities on Xero Universal Viewer
Technology | Remote Viewing Systems | July 27, 2017
Agfa HealthCare announced it has received U.S. Food and Drug Administration (FDA) 510(k) clearance for the Xero Xtend...
Amsterdam University Hospital Brings Sectra Education Portal Online
News | PACS Accessories | July 26, 2017
International medical imaging IT and cybersecurity company Sectra’s solution for medical education and clinical...
News | Enterprise Imaging | July 24, 2017
July 24, 2017 — Insignia Medical Systems has been selected to supply three National Health Service (NHS) Trusts worki
TomTec Unveils TomTec Zero Cardiovascular Viewing Software
Technology | Remote Viewing Systems | July 24, 2017
July 24, 2017 — TomTec Zero is the latest addition to the TomTec portfolio.
Philips Receives FDA 510(k) Clearance for IntelliSpace Portal 9.0
Technology | Advanced Visualization | June 29, 2017
Philips announced it has received 510(k) clearance from the U.S. Food and Drug Administration (FDA) to market...
RamSoft Partners With Gamel to Enhance Patient Care in Peruvian Market
News | PACS | June 23, 2017
RamSoft announced a new partnership with Peru-based medical imaging equipment provider, Gamel. With RamSoft’s...
Fujifilm Exhibits Suite of Enterprise Imaging Solutions at SIIM 2017
News | Enterprise Imaging | June 19, 2017
Fujifilm Medical Systems U.S.A. Inc. presented its comprehensive Synapse Enterprise Imaging portfolio at the 2017...
Vital Images to Address Specialized Workflow and Efficiency Challenges at SIIM 2017
News | Enterprise Imaging | June 01, 2017
An industry expert from Vital Images, Inc. (Vital) is participating in a discussion with the healthcare community on...
Overlay Init