Reversing Nerve Damage: Central Nervous System Inhibits Cell Regeneration, But Stem Cell Treatment May Help
Our nervous system is involved in everything our body does, from maintaining our breath to controlling our muscles. Our nerves are vital to all we do; therefore, nerve pain and damage can heavily influence our quality of life. In Discovery News' latest video, "Why Can't We Reverse Nerve Damage?" host Lissette Padilla explains the central nervous system (CNS) has certain proteins that inhibit cell regeneration, because each cell in the nervous system has a unique function on the pathway, like a circuit, and can't be replaced.
The nervous system can be divided into two sections, with the brain and spinal cord making up the CNS. Nerves are made up of sensory fibers and motor neurons, which comprise the peripheral nervous system. Nerve cells are made up of many parts, but they send signals through threads covered in a protective sheet of myelin. These threads are called axons.
Axons are the long part of the cell that reaches out to neighboring cells to send information down the line. Schwann cells, found only in the peripheral nervous system, are glial cells that produce protective myelin. Schwann cells could potentially clean up damaged nerves, which could make way for healing process to take place and new nerves to be formed.
The problem is these Schwann cells are missing from the CNS. The CNS is comprised of myelin-producing cells called oligodendrocytes. And these cells don't clean up damaged nerve cells at all, hence the damage problem.
However, research is currently underway to examine the potential success of system cell treatment, where stem cells are injected directly at the injury site. It will still take a few years to see the results of such trials, but since the peripheral nervous system doesn't have the same blocking proteins that the CNS has, the idea is Schwann cells could help heal the damage.
So it is possible to regrow nerves, albeit slowly. For instance, if you cut a nerve into your shoulder, it could take a year to regrow. By that time, the muscles in your arms could become atrophied. Researchers are working on helping the body heal faster.