Combo Therapy May Reverse Paralysis
Study Suggests Walking Can Be Restored Without Regrowing Damaged Nerves
Sept. 21, 2009 -- Researchers at UCLA have taken steps toward restoring the
ability to walk after a spinal cord injury that results in paralysis.
Gregoire Courtine and colleagues say a complex combination of drugs, exercise, and electrical stimulation remodels nerve
circuits in the spine of paralyzed rats, allowing them to take weight-bearing
steps and even run on a treadmill.
The trio-treatment regimen involves injecting medication called serotonin
agonists and applying electric currents to the spinal cord below the point of
injury while the animals were on a slow-moving treadmill. Scientists say the
therapy taps into the spinal circuitry responsible for walking motions. It's well known that nerves in the
spine do not need to talk to the brain to trigger rhythmic muscle motions and
Previous studies have shown that tapping into this circuitry can help
patients with spinal cord injuries achieve leg motion but, until now, no one
has been able to manipulate it in a way that allows for full weight-bearing and
In this study, after several weeks of treadmill training, the rats could put
all their weight on their legs and even move them forward, backward, and
sideways similar to voluntary walking.
The findings, presented in this week's online edition of Nature
Neuroscience, suggest that severed nerve fibers do not need to regrow in
order for a paralyzed patient to walk again. The study researchers hope their
discovery leads to a new strategy for restoring motor function in people with
spinal cord injuries. Even after the combo therapy, the rats still needed
assistance walking, but researchers say neuroprosthetic devices would help
people with this task.