It is similar to the protective insulation around electrical wires.
This coating enables the electrical impulses between nerve cells to travel back and forth rapidly.
When myelin becomes damaged, these electrical signals are interrupted and may even stop altogether.
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Damage to the myelin can cause medical conditions such as multiple sclerosis andGuillain-Barresyndrome.
This article discusses the myelin sheath and its function and purpose.
It also goes over some of the medical conditions that affect the myelin sheath.
What Is the Myelin Sheath?
Myelin is made of fat and protein.
Myelin is created by specific types ofglialcells.
In the CNS, glial cells areoligodendrocytes; in the PNS, they are Schwann cells.
What Does the Myelin Sheath Do?
The main function of the myelin sheath is to insulate and protect nerve cells.
This keeps electrical impulses moving quickly and efficiently between one nerve cell and another.
As they get older and the myelin matures and builds up, their movements become smoother and more controlled.
This process continues through adulthood.
How Do Nerve Cells Work?
Nerve cells are made of three parts: the soma, the axon, and the axon terminal.
The soma receives signals from nearby nerve cells.
Nodes of Ranvier Function
The myelin sheath exists in sections called internodes.
Between each internode are small spaces known as nodes of Ranvier.
What Happens if the Myelin Sheath Is Damaged?
These thin projections are calledaxons.
Myelin is vital to a healthy nervous system, affecting everything from movement to cognition.
“Demyelination” describes the destruction of the myelin sheath, the protective covering surrounding nerve fibers.
This damage causes nerve signals to slow down or stop, resulting in neurological impairment.
Eventually, axons degenerate as a result of the chronic myelin loss, leading to nerve cell death.
These include:
Treatment
Current therapies for multiple sclerosis target your immune system.
But now, experts are examining therapies that target myelin.
Can Myelin Be Repaired?
The human body can naturally repair or replace myelin with cells called oligodendrocytes.
In early MS, this process helps keep symptoms under control.
This reduction in the nerve transmission delay suggests that myelin repair occurred along the optic nerve signaling pathway.
Multiple sclerosis is the most common condition affecting the myelin sheaths.
Other conditions are associated with the nerves in the central nervous system or the peripheral nervous system.
Some of these conditions are inherited; for others the cause is not well known.
National Institute of Neurological Disorders and Stroke.Multiple Sclerosis.
Correale J, Marrodan M, Ysrraelit MC.Mechanisms of neurodegeneration and axonal dysfunction in progressive multiple sclerosis.Biomedicines.
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