Drug discovery unlocks stroke paralysed limbs

University of Otago and American researchers have discovered a drug therapy which could dramatically help stroke victims by unlocking paralysed arms and legs and restoring much of their lost mobility.

Results of the 2 year study were published today in the online edition of the international scientific journal Nature.

"This also provides hope for those with traumatic head injuries - the brain mechanisms of repair are similar so there is potential for this to work for them too," study co-author Dr Andrew Clarkson said.

Dr Clarkson, 31, a research fellow at the Otago University departments of psychology and anatomy and structural biology, said human trials using the drug compounds could begin within two years.

One compound, known to enhance cognition and initially developed to treat Alzheimer's disease, is already being tested in people with learning difficulties.

In the first study of its kind, Dr Clarkson and colleagues at the University of California, including neurologist co-author Dr Thomas Carmichael, found the compound, given to mice in slow-release doses, re-activated brain neurons responsible for limb function.

These neurons had initially appeared to be dead or dormant after a stroke.

Six weeks of treatment produced dramatic results, with an extra 50 per cent of gross motor limb mobility consistently gained. Treatment of the mice began three days after the stroke - the equivalent of about three weeks in humans.

Dr Clarkson said the finding was "tremendous" and could be "the biggest therapeutic breakthrough in many years".

The treatment worked on gross motor skills, but it would take further research to clarify whether the drug could also help with the fine motor skills associated with speech.

The research suggests some brain cells affected by strokes or other head injuries have not been killed, as often previously thought, but are effectively "sleeping" and can be reactivated.

- Otago Daily Times