Australian scientists re-grow cut cord

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Australian scientists re-grow cut cord

http://healthorbit.ca/newsdetail.asp?opt=1 & nltid=142081104

8 November 2004 -- In a world first, Australian researchers have

discovered a mechanism for greatly enhancing regrowth of spinal cord

nerves after they are damaged, restoring the ability to walk in mice

within weeks of a spinal cord injury.

The University of Melbourne research team, led by Dr Ann Turnley at the

Centre for Neuroscience and Professor Galea at the School of

Physiotherapy, found that removal of a molecule called EphA4 resulted in

significant regrowth of the spinal nerves following injury.

Mice without EphA4 regained 100% of their initial stride length within

three weeks of the injury and by one month had regained ankle and toe

movement. Their ability to bear weight on the affected limbs, to walk

and climb also improved and continued to do so for at least three months

after the injury.

Anatomical analysis revealed that a large percentage of the spinal cord

nerves had managed to grow across the damaged area of the spinal cord.

Dr Turnley says " when a person injures their spinal cord the effects are

often devastating and there is usually little chance that they will

regain much movement. There is an enormous amount of research being done

around the world to enhance recovery of people with spinal injuries.

" In the past it was believed that adult nerves lacked the ability to

regrow but work over the last few years has shown that not to be true

and we are now beginning to understand the mechanisms behind regrowth

and how to enhance it. Our recent findings are a major step forward in

this regard. "

Dr Turnley says that EphA4 has been known for some time to be involved

in guiding nerves during development but their role in the adult was

unknown.

" The body enhances production of EphA4 following spinal cord injury and

we thought it therefore could prove pivotal in determining the outcome

of injury in the adult central nervous system.

" The surprising result we found was that EphA4 plays a vital role in

activating cells called astrocytes which are in turn responsible for

forming scarring in the damaged spinal cord, leading to inhibition of

nerve regrowth. Mice without EphA4 have very little scarring in the

spinal cord and so the nerves can regrow. "

Findings of the study, which will be published in The Journal of

Neuroscience on November 10, are the work of PhD student Ms Yona

Goldshmit, at the University of Melbourne's Centre for Neuroscience and

School of Physiotherapy,

in collaboration with Professor Bartlett, Director of the

Queensland Brain Institute at the University of Queensland and formerly

at the Walter and Eliza Hall Institute of Medical Research.

Professor Galea says " this finding provides an exciting possibility for

overcoming spinal cord injuries and promoting nerve growth. Increased

EphA4 expression has already been observed in primates following spinal

cord injury and most likely plays a similar role in humans.

" There is now a real prospect of effectively promoting the regrowth of

damaged spinal cord nerves after injury in humans by developing drugs

that can block the EphA4 molecule and stop the scar from forming in the

first place. "

More information about this article:

Elaine Mulcahy

Media Liaison

emulcahy@...

8344 0181

Ann Turnley

Centre for Neuroscience

(03) 8344 3981

0412 704 157

turnley@...