Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Purdue scientists may have found key to halting spinal cord damage

21.06.2005


Purdue University researchers may have isolated the substance most responsible for the tissue damage that follows initial spinal cord injury, a discovery that could also improve treatments for a host of other neurodegenerative conditions.



A research team led by Riyi Shi (REE-yee SHEE) has found that a chemical called acrolein, a known carcinogen, is present at high levels in spinal tissue for several days after a traumatic injury. Although acrolein is produced by the body and is non-toxic at normally occurring low levels, it becomes hazardous when its concentration increases, as it often does in tissue that experiences stresses such as exposure to smoke or pesticides. That list of stresses now includes physical damage, and in the case of spinal injury, acrolein’s hazard may be the key in causing debilitating paralysis that sets in after the initial trauma.

"When a spinal cord ruptures, not only are the traumatized cells at increased risk of damage from free radicals that oxidize the tissue, but the cells also spill chemicals that actually help the free radicals to launch repeated attacks," said Shi, who is an associate professor of neuroscience and biomedical engineering in Purdue’s School of Veterinary Medicine and Weldon School of Biomedical Engineering. "Our latest research indicates that acrolein may be the primary culprit that enables this vicious cycle. Because acrolein has already been implicated in cancer and neurological diseases, drugs that detoxify it could become important for treating not only spinal cord damage but a host of other conditions as well."


The research, which Shi carried out with his student Jian Luo and Koji Uchida of Japan’s Nagoya University, appears in the (still forthcoming) March 2005 issue of the scientific journal Neurochemical Research.

Free radical molecules are well-known enemies of bodily health, and for years, physicians have recommended a diet rich in antioxidants – such as vitamins C and E – which are able to attach themselves to free radicals, detoxifying them. While there is nothing inherently wrong with this approach, Shi said, it might not be getting at the root of some health problems.

"Antioxidants are good scavengers of free radicals, and it’s certainly wise to have plenty of them circulating in your bloodstream," he said. "The trouble is that when free radicals start attacking tissue, it happens in a tiny fraction of a second, after which they are gone. But the acrolein that these attacks release survives in our bodies much longer, for several days at least, and its toxicity is well documented."

For example, acrolein has long been known to cause cancer when its concentration in the body rises, and not much is needed to be dangerous. When a person inhales smog or tobacco smoke, for example, the fluids lining the respiratory tract show an acrolein concentration of about a millimole – not much by measuring-cup standards, but still over 1,000 times more than usual.

"If you took a single grain of salt from a shaker and dissolved it in a liter jug, the water wouldn’t taste very salty," Shi said. "But even that would be more than a millimole, and that’s much more acrolein than the body can handle at once."

Because a high concentration of acrolein also has been linked to neurodegenerative conditions such as Parkinson’s, Huntington’s and Alzheimer’s diseases – all of which progress slowly and resist treatment – Shi’s team decided to see if the chemical was present in another slow-developing, seemingly untreatable condition: the degeneration of the spinal cord after initial traumatic injury.

"Unlike most other parts of the body, spinal cord tissue does not heal after injury," Shi said. "After the initial shock, it actually gets worse. Science has long been aware that some chemicals the damaged cells release are part of the problem, but no one has ever been sure which chemicals are responsible."

When a spine is damaged, the change in its ability to function follows a well-defined pattern. In response to the initial shock, the spine immediately becomes completely nonfunctional but then starts to recover quickly. Over the course of the next few days, in response to the secondary damage, the spine’s function again begins to drop, and within about three days it has leveled off at a point of near non-functionality.

"What our group did was measure the levels of acrolein in the injured spines of 25 guinea pigs for several days following an injury," Shi said. "We found that levels of acrolein peak 24 hours afterward, and they remain high for at least a week. Because acrolein has such a long lifespan and is so toxic, we theorize that it is primarily responsible for the secondary damage that keeps injured spines from healing."

Acrolein’s involvement with other conditions suggests that it could be the key to fighting a number of diseases, Shi said.

"When the brain suffers a stroke, for example, it is deprived of oxygen, which is often thought to be the cause of brain damage. But, in fact, you can starve the nervous tissue of oxygen for up to an hour without harm if only you control the acrolein levels," Shi said. "This paper suggests that the body is generally pretty resilient but that acrolein may be something it can’t handle."

Shi said that some drugs already under development for other conditions could be used to treat neurodegenerative diseases as well.

"Hypertension drugs, which bind to acrolein and detoxify it, are already under study for their added potential to promote liver health," Shi said. "We would like to see whether they also could be modified to treat the conditions we are interested in."

Further research will be necessary to determine how great a role acrolein actually plays in the process of secondary spinal cord damage, but Shi said that once this role is clarified, drugs that counter acrolein’s effects could join the other approaches to treating spinal cord injury under development at Purdue’s Center for Paralysis Research.

"My colleague Richard Borgens and I have already had our hands in developing PEG, a substance that coats damaged spinal cells so that their membranes can heal and also oscillating field stimulator implants that encourage the tissue to regenerate," Shi said. "We are hopeful that detoxifying acrolein will allow doctors to stop the chemical attack cycle as well, adding to the number of treatment methods available."

The center was established in 1987 both to develop and to test promising methods of treatment for spinal cord injuries. The center uses its close affiliation with the Department of Veterinary Clinical Sciences in the College of Veterinary Medicine to move basic laboratory methods into clinically meaningful veterinary testing.

This research was funded in part by the National Institutes of Health and the State of Indiana.

Chad Boutin | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Health and Medicine:

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

nachricht Flexible sensors can detect movement in GI tract
11.10.2017 | Massachusetts Institute of Technology

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>