Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


In Young Rats, Researchers Find a Reaction to Spinal Cord Injury That Speeds Recovery

Finding surprises researchers, who discovered that young rats mend more quickly because cells near the injury site respond differently than in adults

Neuroscientists had long believed that the only way to repair a spinal cord injury was to grow new neural connections, but researchers at Georgetown University Medical Center have found that, especially in young rats, powerful cells near the injury site also work overtime to restrict nerve damage and restore movement and sensation.

The same process does not work as efficiently in adult rats and thus recovery time is much longer, the researchers also discovered. But they say that now that they know such a mechanism exists, it may be possible one day to “switch” these cells on therapeutically ? and possibly help humans function better following serious spinal cord injuries.

“No one knew cells in the spinal cord acted to protect nerves in this way, so it gives us some hope that in the future we could stimulate this process in the clinic to enhance recovery and ensure the best outcome possible for patients,” said the senior author, Jean R. Wrathall, Ph.D., professor in the Department of Neuroscience.

... more about:
»Myelin »Nerve »Recovery »Wrathall »axons »sheath »spinal

“This is an animal study, however, and there is much work to do to understand more about this process and how it might be altered,” Wrathall said. The study, whose first author is graduate student Philberta Y. Leung, is published in the November 2006 issue of the journal Experimental Neurology.

At the least, Wrathall said, the study reveals surprising new information about nerve cell recovery that neuroscientists can now explore.

In vertebrates, the nervous system uses a two-way transmission system to communicate the electrical impulses that lead to muscle movement and the perception of sensation. In humans, hundreds of thousands of nerve fibers (axons), which can be several feet in length, run through the spinal cord like a two-lane road. Half of these axons connect the brain to distant muscles, and the other half links the body to the brain.

Axons cannot regenerate when they are completely severed, but researchers believe that in a partial injury, surviving nearby axons that serve the same general body area and function can “sprout” new connections to those injured nerve cells that have lost some of their axons. In studying spinal cord injury in rats ? the usual model for this kind of investigation ? researchers had thought that younger rats (“pups”) regain function faster because this sprouting occurs more quickly and proficiently than in older rats. “Just as young trees grow more quickly if you prune them than do older trees, we thought than in young animals, surviving axons would sprout new, and longer, axonal connections more readily,” Wrathall said.

But the findings surprised them. “We didn’t see that sprouting was faster or better in younger than in adult rats after a partial spinal cord injury,” she said. Instead, they saw distinctions in what occurred in cells within the spinal cord at the site of injury. Leung and Wrathall specifically discovered that in the pups, specialized neural stem cells grew vigorously after injury and within one week, many oligodendrocytes, cells whose function is to provide a protective myelin sheath to axons, were produced..

The researchers believe that these activated cells wrap nearby surviving axons with extra myelin sheathing in order to protect them and support their function after injury.

“The ability of axons to transmit their signals is greatly dependent on the insulation provided by their myelin sheaths, and we know that axons near the site of injury eventually can die due to loss of this myelin,” Wrathall said. “So we believe these stem cells work to protect healthy axons against toxic factors in the microevironment.”

Adult rats do not activate these specialized cells to the same extent as the pups do after injury, for reasons that are not understood, she added.

“We hadn’t expected these results, but they are exciting for the field of spinal cord injury and recovery,” Wrathall said. “Now that we know that the difference in the local cell response to injury means a quicker recovery, we might be able to eventually exploit that innate healing ability in humans.”

She added that these new findings might also be relevant to multiple sclerosis, a disease caused by loss of an axon’s protective myelin sheath.

The study was funded by grants from the National Institutes of Health

About Georgetown University Medical Center
Georgetown University Medical Center is an internationally recognized academic medical center with a three-part mission of research, teaching and patient care (through our partnership with MedStar Health). Our mission is carried out with a strong emphasis on public service and a dedication to the Catholic, Jesuit principle of cura personalis -- or "care of the whole person." The Medical Center includes the School of Medicine and the School of Nursing and Health Studies, both nationally ranked, the world-renowned Lombardi Comprehensive Cancer Center and the Biomedical Graduate Research Organization (BGRO).

Laura Cavender | EurekAlert!
Further information:

Further reports about: Myelin Nerve Recovery Wrathall axons sheath spinal

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>