Stem Cell - Archive

Treatment Combination Helps Paralyzed Rats to Walk (5/04)

In a major step forward in research on spinal cord injuries, scientists in Miami reported in May that an innovative combination of treatments allowed paralyzed rats to regain up to 70% of their ability to walk. The research is a “significant advance” that may help some of the 243,000
Americans with spinal cord injuries get out of their wheelchairs. Researchers at the Miami Project to Cure Paralysis say they have found a way to promote the growth of nerve fibers in damaged spinal cords and prevent post-injury nerve death. A spinal cord injury damages the nerve circuits that carry messages from the brain to the body.
Recent research has focused on transplanting cells [adult stem cells] from peripheral nerves outside the brain and spinal cord into the damaged area as a bridge across the injury. But new nerve fibers didn’t go beyond the bridge because of problems such as growth-inhibiting molecules, researcher Mary Bartlett Bunge says. Bunge, along with Damien Pearse, lead author of the study published in Nature Medicine, and colleagues, devised a three-part approach that begins shortly after the injury occurs. The research did not involve the politically sensitive issue of [embryonic] stem cells, but used cells from adult rats [adult stem cells]. Researchers first inject the rats with Rolipram, a drug that stops the loss of a growth-enhancing chemical called cyclic AMP, which occurs just after a spinal cord injury. Researchers then take cells from the rats’ peripheral nerves, grow those in the lab and transplant them into the injured area, followed by one-time injections of cyclic AMP above and below the transplant site. The injections raise the levels of cyclic AMP, enhancing the environment for the growth of nerve fibers, Bunge says. Naomi Kleitman of the National Institute of Neurological Disorders and Stroke says the strategy is a “significant advance over what has been reported before” and is “likely to be applicable clinically if the progress continues.” The animals went from being able to take only occasional steps to walking in a coordinated way, with hind and fore paws working together, Kleitman says. “That’s a much bigger effect” than has been previously seen, she says. The research focused on a common but less severe injury than that suffered by actor Christopher Reeve. But, Miami Project spokesman Scott Roy says, it could lead to treatments for all kinds of injuries. [http://www.usatoday.com/news/health/2004-05-23-paralysis-rats_x.htm Anita Manning, USA Today: 5/23/2004]