Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Uric acid may help reduce effects of spinal cord injury

15.02.2005


Increasing levels of uric acid, a metabolic breakdown product found in blood and urine, may help cut some of the potentially devastating "secondary" cellular damage that occurs following a spinal cord injury, say researchers at Jefferson Medical College. The finding may lead to new treatments for such injuries.

After a spinal cord injury, the body’s inflammatory response may actually make things worse, releasing a variety of potentially harmful chemicals that can make the injury more severe. J. Craig Hooper, Ph.D., associate professor of microbiology and immunology at Jefferson Medical College of Thomas Jefferson University in Philadelphia and at Jefferson’s Kimmel Cancer Center and his colleagues there and at the University of Messina in Italy looked at whether uric acid treatment could actually prevent some of this secondary damage following such an injury in mice. Uric acid was known to reduce inflammation damage related to a compound call peroxynitrite.
They found that mice that received uric acid just before and right after an experimental spinal cord injury recovered motor function both faster and to a greater extent than mice that received only saline. Subsequent tests found that the uric acid actually prevented inflammation and some damage. Tests in cell culture showed that uric acid protected spinal cord neurons from peroxynitrite-related damage. The scientists report their findings Feb. 14, 2005 in the Proceedings of the National Academy of Sciences.


According to Dr. Hooper, secondary spinal cord damage – the so-called destructive cascade – begins within a few hours after the initial injury. "The effect is driven by nonspecific cells such as neutrophils," he explains, a type of white blood cell and a key player in the body’s inflammatory response to injury. "We know neutrophils make peroxynitrite, which is a major trigger in opening the blood-brain barrier."

Dr. Hooper says peroxynitrite is known to contribute to cell damage in neurodegenerative disorders, and is known to be produced as a result of the body’s inflammatory response.

"In the paper, we showed that uric acid modulates peroxynitrite’s effects," Dr. Hooper says. "It’s incredibly useful in preventing the damage related to peroxynitrite as a toxic molecule. More importantly, it stops the secondary injury cascade by preventing the neutrophils from getting into spinal cord tissues through the blood-brain barrier."

Dr. Hooper and his co-workers compared injured rats that received saline to spinal cord-injured rats that were given uric acid. "The injury causes a tremendous amount of damage in the mice – less than 50 percent range of motion in one or two hind limb joints remain immediately following the injury," he says. Those given saline had regained movement of up to two or three joints. The uric acid-treated rats recovered to where they could support their own weight, despite having some disabilities due to the damage.

Next, the scientists want to better understand how the peroxynitrite-mediated processes actually work, which is particularly important to learning how to control immune responses in the central nervous systems of both in mice and humans. "We’re looking at various models to distinguish between peroxynitrite pathology and its effects on blood-brain barrier function," he says.

"We want to establish the precise timing where the inactivation of peroxynitrite will have therapeutic benefit," he says. "In the spinal cord, we know many of the changes occur within 24 hours. It’s certainly feasible to give someone uric acid immediately and raise levels in 50 minutes. Whether or not this should be a first-line response is unknown.

"There is a range we could work with in raising levels before there’s a problem, such as in gout," he says, referring to an ailment characterized by excessive uric acid. "We know that the human uric acid baseline is higher than that in mice, but we also know that the damage we see in the human spinal cord after injury is very similar to that seen in the mice.

"Raising uric acid levels in humans similarly to the rise we cause in the mouse should be sufficient to block peroxynitrite," Dr. Hooper says. "Our natural levels of uric acid are not sufficient. Moreover, someone with lower levels who has a spinal cord injury could definitely suffer greater damage."

Steve Benowitz | EurekAlert!
Further information:
http://www.jefferson.edu

More articles from Life Sciences:

nachricht Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology

nachricht Migrating Cells: Folds in the cell membrane supply material for necessary blebs
23.11.2017 | Westfälische Wilhelms-Universität Münster

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>