14 DAY TRIAL // For many years, severe spinal cord injuries were synonymous to paralysis, and living a life in the wheelchair. Intense trauma to the cord, the variety that ripped apart nerve connections, meant that electrical signals from the brain no longer reached their destinations. Now, thanks to a collaboration of researchers, paralysis may become a thing of the past. The team managed to develop a method of promoting robust healing in the spinal cord, which sees nerve connections restored faster than ever.
The findings have tremendous potential for the development of new therapeutic approaches to addressing paralysis and other motor function impairments, which are caused by damage to the spinal cord. The new work was conducted by investigators at the University of California in Irvine (UCI), the University of California in San Diego (UCSD), and the Harvard University. The researchers say that their new technique was developed when they learned how to turn back the developmental clock in a molecular pathway. This pathway plays an extremely important role in the growth of corticospinal tract nerve connections, they explain further.
The “clock” was set back by deleting a phosphatase and tensin homolog enzyme called PTEN. This protein controls the mTOR molecular pathway, which plays an active role in regulating cellular growth. PTEN activates once repair to a damage tissue is complete, thus inhibiting mTOR. By shutting down the enzyme, the molecular pathway is clear to do its job a lot faster and more efficiently. Back in 2008, Children’s Hospital Boston senior neurology researcher and Harvard Medical School expert Zhigang He managed to show in mice that interventions on PTEN allowed the regeneration of neural connections from the eye to the brain. The mice in that experiment had all suffered optic nerve damage.
Together with colleagues Oswald Steward (at UCI) and Binhai Zheng (at UCSD), He then began to investigate whether the same type of treatment was possible for spinal cord injuries as well. “Until now, such robust nerve regeneration has been impossible in the spinal cord. Paralysis and loss of function from spinal cord injury has been considered untreatable, but our discovery points the way toward a potential therapy to induce regeneration of nerve connections following spinal cord injury in people,” says Steward, who is a UCI professor of anatomy & neurobiology.
He is also the director of the Reeve-Irvine Research Center at the university. The team published the full details of its investigations in the latest online issue of the top-rated scientific journal Nature Neuroscience. The work could address 2 million people in the United States alone, which statistics show suffer from some form of paralysis induced by spinal cord damage.