Thursday, September 15, 2011
Bridge to Spinal Cord Injury Cure
Scientists restored breathing function in mice by bridging a spinal cord injury and regenerating lost nerve connections to the diaphragm.
More testing is necessary, but researchers are hopeful their technique will quickly be used in clinical trials.
Restoring breathing is the a top priority for people with upper spinal cord injuries, researchers say. Many rely on ventilators to breathe, which can be inconvenient and potentially dangerous.
“We use an old technology peripheral nerve graft and a new technology enzyme to restore breathing to nearly normal,” says Jerry Silver, professor of neurosciences at Case Western Reserve University and senior author of a study published in Nature.
Using a graft from the sciatic nerve, surgeons have been able to restore function to damaged peripheral nerves in the arms or legs for 100 years. But, they’ve had little or no success in using a graft on the spinal cord.
Nearly 20 years ago, Silver found that after a spinal injury, a structural component of cartilage, called chondroitin sulfate proteoglycans, was present and involved in the scarring that prevents axons from regenerating and reconnecting.
Silver knew that the bacteria Proteus vulgaris produced an enzyme called Chondroitinase ABC, which could break down such structures. In previous testing, he found that the enzyme clips the inhibitory sugary branches of proteoglycans, essentially opening routes for nerves to grow through.
In the new study, the researchers bridged a spinal cord injury at the second cervical level using a section of peripheral nerve and injected Chondroitinase ABC.