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 Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>