Spinal cord damage blocks the routes that the brain uses to send messages to the nerve cells that control walking. Until now, doctors believed that the only way for injured patients to walk again was to re-grow the long nerve highways that link the brain and base of the spinal cord. For the first time, a UCLA study shows that the central nervous system can reorganize itself and follow new pathways to restore the cellular communication required for movement.
Published in the January edition of Nature Medicine, the discovery could lead to new therapies for the estimated 250,000 Americans who suffer from traumatic spinal cord injuries. An additional 10,000 cases occur each year, according to the Christopher and Dana Reeve Foundation, which helped fund the UCLA study.
Imagine the long nerve fibers that run between the cells in the brain and lower spinal cord as major freeways, explained Dr. Michael Sofroniew, lead author and professor of neurobiology at the David Geffen School of Medicine at UCLA. When theres a traffic accident on the freeway, what do drivers do? They take shorter surface streets. These detours arent as fast or direct, but still allow drivers to reach their destination.
We saw something similar in our research, he added. When spinal cord damage blocked direct signals from the brain, under certain conditions the messages were able to make detours around the injury. The message would follow a series of shorter connections to deliver the brains command to move the legs.
Using a mouse model, Sofroniew and his colleagues blocked half of the long nerve fibers in different places and at different times on each side of the spinal cord. They left untouched the spinal cords center, which contains a connected series of shorter nerve pathways. The latter convey information over short distances up and down the spinal cord.
What they discovered surprised them.
We were excited
|Contact: Elaine Schmidt|
University of California - Los Angeles