Scientists have figured out the molecular mechanism of myelination of axons
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Scientists have figured out a molecular signaling mechanism that gives rise to the buildup of "electrical insulation" of neurons. It, in turn, has a beneficial effect on the ability of the central nervous system (CNS), in particular the brain.
Researchers from the system of American National Institutes of Health (NIH) conducted the experiment with mouse neurons. The main goal was to find out how the work of neurons affects the growth of their insulating envelope and what gives the signal to such growth? Rather, of course, the shells are not bodies of neurons, but axons - these long processes of nerve cells that carry "messages" to other cells.
It is known that adjacent cells-oligodendrocytes-are responsible for the formation of the myelin sheath of axons in the CNS. The myelin produced by them is wound on an axon and acts as an "electric cable insulation". In this case, the presence of such a membrane (myelination) increases the rate of passage of the nerve impulse by an order of magnitude.
This process in the central nervous system and the human brain is most intense from birth to about 20 years, when a person consistently learns to hold his head, walk, talk, reason logically, and so on. On the contrary, in a number of diseases (such as multiple sclerosis) myelin sheaths of axons collapse, which worsens the brain and CNS.
Understanding the mechanism of launching myelination would help in developing drugs for such diseases, in prolonging active youth.
In a series of experiments with neurons in a Petri dish, biologists from the United States established the following. The primary signal for myelination is the electrical activity of the neuron itself. The higher it is, the more it will receive myelin.
In the process of electrical stimulation, the cultured nerve cells released a neurotransmitter, glutamate. He was a call for oligodendrocytes, placed in the same environment. The latter formed contact points with the axon, exchanged chemical signals with it, and eventually began to cover it with myelin sheath.
At that, isolation around one or another axon of a nerve cell was practically not formed if the axon was not electrically active. Similarly, the process was completely skewed, if scientists artificially blocked the release of glutamate in the neuron, transfers Medical Xpress.
It turns out that the powerful myelin isolation in the brain receives the most active axons, which allows them to further work even more effectively. And an important role in this process is the glutamate signaling device. (The results are published in Science Express.)
[