Is it true that human nerve cells are not restored?

“Nerve cells die from stress and do not restore,” you can hear when we are advised not to be nervous on trifles. We decided to check if the connection of stress with the death of nerve cells is confirmed and whether they are restored.

In art works, it is often possible Meet The statement that you should not be nervous, otherwise the nerve cells are not restored. Moreover, this thought is found not only in artistic prose the second half of the 20th century, when neurobiology only became as a science, but also in quite modern literature. The same thesis is used in Popular memes.

All cells of the human body have a similar life cycle. Usually it consists of the formation of a cell, division and death. But in two types of cells the process of division genetically Disconnected - In mature neurons and in the cells of the heart muscle. Physiological (ensuring its integrity and adaptive reactions) and pathological (aimed at compensating for the effects and/or consequences of the impact of the damaging factor) can lead to the death of the cells. The pathological influence (for example, hypoxia) can be irreversible and reversible. In the case of an irreversible influence, the cell dies, in the case of the reversible, it has a chance to restore. This also applies to nerve cells.

The human nervous system is divided into central and peripheral. The cells of the peripheral system are capable of relatively good regeneration - due to this, for example, can Restore Sensitivity in a cut and re -sewn limb. The cells of the central nervous system are restored longer And more difficult, this determines a long rehabilitation after a stroke or spinal injuries.

The nervous tissue of both of our nerve systems consists of two types of cells: neurons and glia cells. Gliya cells carry out auxiliary functions. They, like an island, cover neurons. In some diseases, this shell is destroyed - for example, with multiple sclerosis. However, it is capable of restoration. Unfortunately, this process does not proceed quickly and slows down even more as the disease progresses. To date, clinical Testing several drugs capable of suggest Their developers, restore the damaged shell.

Now let's move on to the main cells of the nervous tissue - to neurons. Neuron is an electrically excitable cell that takes from the outside, processes, stores, transmits and displays information outside. It consists of a nucleus, body and processes similar to tentacles: axon and one or more dendrites.

In case of damage not only the shell, but also themselves, neurons still have the potential for recovery. Recently a group of scientists from Cambridge University Opened A special protein that allows them to recover. The introduction of this protein is potentially able to treat glaucoma in humans (since the visual nerve atrophies with glaucoma).

Scientists Countedthat humans have about 86 billion neurons, 16 billion of which are in the cortex of large hemispheres. For comparison, in the bark of the hemispheres Black dolphin (or grinds) 37.2 billion neurons, and the African elephant has a total of 257 billion - though 98% of its neurons Located In the cerebellum, not in the cerebral cortex. On a day in the human body, up to a dozen thousand nerve cells can die. Then how does a person preserve memory and intelligence until very advanced years? There are several explanations for this.

Firstly, The death of neurons is an absolutely natural process for the human body. And largely due to this process, our nervous system is so plastic. For example, in roundworms throughout life is exactly 162 neuron. They do not die. In the same way arranged Nervous system of mollusks and insects. It is precisely because of a fixed amount of neurons that these animals are not able to significantly change their behavior and study.

Since neurons are one of the most resource -fitting cells in our body, the body itself Speaks From the least active neurons that have few connections with other cells. The functions of the "murdered" neuron right there Take it The neighboring ones, enlarging in size and forming new connections.

Secondly, neurogenesis (the formation of new neurons instead of lost) still exists. For the first time, Joseph Altman reported him in 1962. He Published In the journal Science, the article “Are new neurons formed in the brain of mammals?”, In which he spoke about his experiment. With electric shock, he destroyed the area in the brain of the rat and introduced there a radioactive substance that could penetrate into new cells. A few months later, new radioactive neurons appeared in other parts of the animal’s brain. However, then his discovery did not cause a wide scientific interest. For the second time, the neurogenesis was “discovered” after almost 20 years. Professor Fernando Notteb from the University of Rockefeller provedthat the marriage songs of the males of Canaries change from season to season precisely because of a significant renewal of cells in the vocal center of the brain. In parallel with them, Soviet professor A. L. Polenov discovered Neurogenesis at amphibians. In 1998, Peter Ericksson and Fred Gage proved Neurogenesis in humans. Today it is known that there are at least three places of formation of new neurons: hippocampus, olfactory bulbs and an almond -shaped body.

However, neurogenesis is not a classic division, but rather the transformation process. The predecessor cell in the case of neurogenesis is not neurons, but other types of cells-for example, cells Gliya Or stem Cells. According to the newest research There are even non-drug methods to improve neurogenesis-in particular, active sports and walks, as well as 3D video trips.

Now the study of neurogenesis is one of the most promising areas of medicine. After all, if it turns out to be a controlled way to launch the formation of new neurons in humans, then you can significantly advance into the treatment of Diseases of Parkinson and Alzheimer, as well as give the possibility of rehabilitation of patients with spinal injuries.

By the way, a person loses the largest number of nerve cells not in the last years of his life, but in the intrauterine period - about 70% of the initially laid. The brain continues to lose neurons further, but not so intensively. There are many causes of the death of neuron, one of which, of course, is stress. However, this is not about banal experiences about problems at work or difficulties in personal life. If the body reacted to each stress with the destruction of part of the nervous tissue, then we would very quickly loseimedness and die. We are talking about really serious external influences. For example, c experiment With rats as a source of stress, periodic shocks were used, the inclusion of sharp and loud sounds, as well as the room of animals in narrow cells. Moreover, after the source of stress has been removed, organic damage to their brain Remained. Scientists believe that in people, like all other mammals, similar processes occur under the influence of stress.

Thus, by the aggregate of the scientific data available today, we can say that stress really acts as one of the factors of the death of the cell along with many others. In this case, with reversible damage, nerve cells can be restored, and with irreversible, the human brain has enough “supply” new neurons.

Most of the untruth

What do our verdicts mean?

Read on the topic:

1. https://www.health.harvard.edu/mind-and-mood/can-you-new-new-brain-cells
2. https://nplus1.ru/news/2020/03/03/genetherapyhd
3. http://neuronovosti.ru/novaya-nejromediatornay-sistema-na-osnove-sle Dovyh-Aminov-Sposobna-Vosstanavlivat-Nervnye-Kletki-U-Vzroslyh-Sosobej/