Nov. 27 (UPI) -- A new treatment could restore breathing and limb function to millions of people worldwide living with chronic spinal cord injuries.
Researchers of a new study published Tuesday in the journal Nature Communications focused on treating axons, cells that can regenerate nerve extensions in a damaged spinal cord.
"For the first time we have permanently restored both breathing and some arm function in a form of high cervical, chronic spinal cord injury-induced paralysis. The complete recovery, especially of breathing, occurs rapidly after a near lifetime of paralysis in a rodent model," Jerry Silver, professor of neurosciences at Case Western Reserve University School of Medicine and study senior author, said in a press release.
Scientists injected the chondroitinase enzyme into the severed spinal cords of rats. The enzyme clears out inhibitory molecules freed axons up to help speed up the regeneration process.
"The strategy was to use a simple, one-time injection of an enzyme, chondroitinase, that breaks down the inhibitory proteoglycan molecules. The enzyme was administered, not within the lesion itself, but lower down within the spinal cord where motor nerve cells reside that send axons out to the diaphragm and forearm," Silver said.
The researchers say that rats treated immediately after spinal injury only got a minor benefit compared to animals with chronic spinal cord damage.
Overall, 70 percent of the rats could use their forelimbs to move around and 60 percent saw improved diaphragm function.
Six months later, the treatment restored complete diaphragm and partial forelimb function on the severed side of the rats spines.
"Our data illustrate the relative ease with which an essential motor system can regain functionality months to years after severe spinal cord injury," Silver said. "The treatment regimen in our study is relevant to multiple types of chronic incomplete spinal traumas, and we are hopeful it may also help restore motor function following spinal cord injury in humans."