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 New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia

nachricht New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

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

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>