The generation of a thin myelin sheath during remyelination — one that continues to protect nerve cells over time — is indicative of the long-term health and activity of the central nervous system (CNS) in demyelinating diseases such as multiple sclerosis (MS), a new study shows.
These findings, which aim to settle a scientific debate about CNS healing, are reported in the study “Thin myelin sheaths as the hallmark of remyelination persist over time and preserve axon function,” published in the journal PNAS.
The myelin sheath is an insulating layer of lipids (fats) and proteins that wrap around nerves. It works to speed the transmission of signals from the nerves to muscles, in order for a person to carry out activities such as walking, talking, and breathing.
Remyelination, which refers to a process through which the body rebuilds the myelin sheath when it has been stripped away due to disease, is the most powerful form of repair for the brain and the spinal cord in patients with a demyelinating disease. In the recovery phase of a disease, the body will completely remyelinate areas that have been stripped of myelin.
MS is a demyelinating disease, and in these patients remyelination can be quite extensive. The ability of the body to remyelinate nerve cells can also decline as a person ages.