Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hibernating Squirrels Provide Clues for Stroke, Parkinson’s

04.11.2002


A compound that enables squirrels to hibernate may one day help minimize brain damage that results from stroke, according to a researcher at the Medical College of Georgia and Veterans Affairs Medical Center in Augusta.




In an animal model for stroke, delta opioid peptide reduced by as much as 75 percent the damage to the brain’s striatum, the deeper region of the brain and a major target for strokes, according to Dr. Cesario V. Borlongan, neuroscientist.

In fact, evidence suggests that the compound, which puts cells in a temporary state of suspended animation, may help protect brain cells from the ravages of Parkinson’s disease as well.


“When the animals were introduced to an experimental stroke, then injected with delta opioid peptide, we could see a reduction in the damage done by stroke; brain damage is reduced and the neurological deficits associated with stroke are definitely reduced,” Dr. Borlongan said.

More extensive animal and human studies are needed but Dr. Borlongan said the peptide, which occurs naturally in man and may play a role in the body’s effort to protect the brain, should one day minimize stroke damage.

His stroke work garnered the International College of Geriatrics Psychoneuropharmacology Award presented this month at the college’s annual meeting in Barcelona, Spain.

The original insight about squirrels and delta opioid peptide came from work by Dr. Tsung-Ping Su at the National Institutes of Health. In the 1980s, Dr. Su was studying hibernation and found increased levels of the compound. Dr. Su also found that when he gave non-hibernating squirrels more of the compound, the previously hyperactive critters began hibernating even in the summer.

Although there’s no hard evidence that humans hibernate, they do have endogenous levels of delta opioid peptide that Dr. Borlongan believes may play a role in natural protective mechanisms.

During hibernation, levels of the peptide increase and the metabolic rate and energy demands of the entire animal drop dramatically. That led Dr. Borlongan to wonder if that same state might help protect brain cells specifically. “Our thinking here is that if we take this drug, probably brain cells are going to go into this mode of hibernation. So if you get a stroke or some other neurological disorder, most of the brain cells will be protected.”

When Dr. Borlongan gave high doses of the compound to the animal model for stroke, the rats -- which are not known to hibernate -- looked sleepy in the hours following but recovered dramatically. In fact, at least in rats, the levels of endogenous peptide increased immediately following a stroke, which makes him suspect that the levels may also increase in humans.

Patients who receive more of this compound in the hours after stroke -- much as many now receive TPA or aspirin -- may get significant protective benefits. “The oxygen needs were dramatically reduced: that is how it works to protect the brain,” Dr. Borlongan said of the animal cells.

To study the role in Parkinson’s, he put varying levels of delta opioid peptide into a culture containing dopaminergic cells, which produce dopamine, a key cell communicator deficient in Parkinson’s. He found that those that got the most peptide survived the longest. In an animal model for the disease, the reduction in dopamine levels was far less in the animals receiving the highest doses of delta opioid peptide.

These findings, presented at the Barcelona meeting and reported partially in the journals NeuroReport and Cell Transplantation, point to the potential of the compound but also to the need for additional animal studies before moving toward clinical trials, Dr. Borlongan said.

One critical issue is that the animal model for stroke has only a single stroke and the majority of humans have a second stroke within months. One of his many goals is to develop a better animal model and see if compounds such as delta opioid peptide and TPA can help patients avoid subsequent strokes.

Other issues that need study are potential side effects, such as how well do the cells function after hibernation; animal models were sleepy while getting the drug but they functioned well afterward, he said. “My feeling is that sleep could be a correlate of hibernation.”

The researcher believes this cell hibernation may have other roles as well, including slowing the aging process. Its potential for helping donated livers, hearts and kidneys remain viable longer until they are transplanted already is being explored by others in clinical trials.

Dr. Borlongan, who joined the MCG faculty in February after completing a senior staff fellowship at the NIH’s National Institute on Drug Abuse, had NIH support for his work prior to joining the MCG faculty. He now has a VA Career Development Award. Several grant applications are pending.

This summer he also received the Rafaelsen Fellowship Award from Collegium Internationale NeuroPsychopharmacologicum in Montreal for his work in brain-cell protection strategies and neural transplantation. And, he was recently elected a councilor for the American Society for Neural Transplantation and Repair.


Please email comments, suggestions or questions to:
Toni Baker, tbaker@mail.mcg.edu.

Toni Baker | EurekAlert!
Further information:
http://www.mcg.edu/
http://www.mcg.edu/news/2002NewsRel/Borlongan.html

More articles from Health and Medicine:

nachricht Malaria Already Endemic in the Mediterranean by the Roman Period
27.07.2017 | Universität Zürich

nachricht Serious children’s infections also spreading in Switzerland
26.07.2017 | Universitätsspital Bern

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: Physicists Design Ultrafocused Pulses

Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.

Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

Programming cells with computer-like logic

27.07.2017 | Life Sciences

Identified the component that allows a lethal bacteria to spread resistance to antibiotics

27.07.2017 | Life Sciences

Malaria Already Endemic in the Mediterranean by the Roman Period

27.07.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>