How long does a neuron live?

Neurons are specialized cells that fulfill a wide variety of very important functions for the proper functioning of the nervous system and, therefore, of the entire organism. These very important cells may have a longer life than many people realize.

When trying to think about how long a neuron lives, it is quite possible that the idea that they do not usually live for very long comes to mind. time we have probably heard, read or discovered somewhere that the cells of our body tend to be destroyed and renewed in a continued; however, this process is not the same in the case of neurons.

In this article we are going to explain how long a neuron lives; But first, we will see exactly what a neuron is, what its main functions are, and we will also briefly explain the different types of existing neurons.

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What exactly is a neuron?

Neurons are specialized cells that are responsible for making up the nervous system. Among their main functions, it should be noted that they are responsible for

receive, process and transmit information through two different types of signals: chemical and electrical, this being possible due to the electrical excitability of the plasmatic membrane they possess, which is a layer that delimits the entire cell.

Neurons are divided into different parts: the cell body or soma, the nucleus, the axon, the dendrites, the cell sheath. myelin, the nodes of Ranvier, the substance of Nissl, the synaptic buttons and, finally, we can find the cone axonal.

Likewise, neurons are responsible for receiving various stimuli and also for the conduction of nerve impulses between neurons through connections called “synapses”, or also with other kinds of cells (eg. g., muscle fibers).

There are three kinds of neurons: sensory neurons, which are usually responsible for transporting information from the sense organs (p. g., the eyes) to our brain; motor neurons would be those that have long axons and are responsible for transporting indexing from the central nervous system (CNS) to the muscles and also to the glands of the Body; Finally, there are the interneurons, which are the ones with shorter axons and are responsible for establishing communications between neurons, never with muscle fibers or sensory receptors.

Secondly, neurons are created from stem cells in the subgranular zone in the hippocampus and also in the subventricular zone in a process known as "neurogenesis" (the birth of new neurons). Normally the neurons of adults do not have the capacity to reproduce; however, some more recent studies affirm that it has been possible to observe that some types of neurons do reproduce.

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How long does a neuron live?

Let us now address the issue of the longevity of human neurons. If we stop to think how long a neuron lives, we probably imagine that these specialized cells of our nervous system do not live very long, as it happens with other types of cells present in our organism; However, this idea is not true since the lifespan of neurons differs greatly from that of other cells that are normally reproduced and destroyed continuously throughout our lives.

Thanks to the research carried out over the last few years, it has been possible to verify that the neurons that we have in our brain are the same age as us, since they were present there from our birth, unlike what happens with the cells of other parts of our body that are replaced from time to time time (eg. g., skin cells usually renew each month).

Therefore, if someone were to ask us how long a neuron lives, they would probably be surprised by our answer now that we have it. find, thanks to the data revealed by various investigations that neurons could live even longer than us. Moreover, some scientific theories have developed the hypothesis about the possibility that they can live infinitely.

If this were true, with future advances in science and medicine, along with good lifestyle habits, if the human being managed to significantly increase their life expectancy (p. g., making it past 120 years) neurons will continue to function, which could be quite hopeful.

In addition, through specialized research on the subject, it has been observed that when a person dies, a large percentage of their neurons remain intact; In other words, those neurons that accompany a person until the end of his days actually did so from the moment he was born. But despite this, when the person's body stops working, the neurons are progressively destroyed.

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Does that mean that neurons are not destroyed throughout our lives?

There is a study that was carried out in 2013 by the neurosurgeon Magrassi and his collaborators where investigated with some mice that consisted of making a neuronal implant from the brain of some mice to that of others mice. The results were surprising, since these transplanted neurons lived up to 36 months on average longer than the mice that carried them in their brains.

The conclusion of this study reaffirmed the hypothesis of other investigations about the possibility that some neurons could perhaps be immortal if they were in a body that was capable of maintaining them with life.

Now, even if there are neurons that are born with a person and die when he dies, it does not mean that all the neurons that person has in the brain live the same as him. In fact, The brain can keep a part of the total number of neurons that the person had at birth for the rest of its life..

It is worth mentioning, on the other hand, that there is a process known as "neuronal pruning", by which over the years those synaptic connections that are not used are eliminated, being a process contrary to what happens when certain connections between neurons are used a lot so that these are reinforced and could also interconnect with new ones.

Secondly, neuronal death is usually caused by some degenerative disorders, as can be the different types of dementia and it could also be caused by different traumas experienced, especially at an early age or due to some infectious, immune or inflammatory diseases, among others. However, another process known as neuronal regeneration or neurogenesis can also occur, which would be that capacity of neurons to regenerate, although this usually only occurs in some areas of the brain, so it is not very usual.

This neurogenesis normally occurs in two parts of the brain, the olfactory bulb, which is the brain area responsible for smell (although in this case it normally only happens until 18 months of age). age) and the hippocampus, which is the brain area that is especially involved in memory and also in navigation through the environment. Beyond isolated cases and certain brain regions, such as those just mentioned, the rest of the neurons we have are the same age as us and will accompany us for the rest of our lives life.

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Could the lifestyle we lead influence the lifespan of our neurons?

When reflecting on how long a neuron lives, it may also come to mind the question about whether our lifestyle could influence the lifespan of these cells. This question could be answered with a yes but with nuances since there are various factors that influence the life of neurons, as well as health in general, which escape from our controls (eg. g., suffering from some diseases).

However, it is known that there are various factors that we can control and that can favor the prolongation of life and, therefore, the maintenance of a greater number of neurons the greater time possible.

Therefore, what we can do to keep our neurons in better condition are good habits and a healthy lifestyle (p. g., maintaining a good diet, practicing physical exercise, learning continuously throughout our lives, etc.) that good habits have been found to prevent cognitive decline while helping to strengthen synapses cerebral.

On the other hand, bad habits, such as alcohol and other substance abuse, as well as the sedentary and the lack of learning in a continuous way, although no conclusive results have been found about the hypothesis that states that they could destroy neurons directly, it has been observed that they harm the development of synapses neurons and this can affect various brain connections responsible for reinforcing various functions such as memory or reasoning logic, among others.

Also, If these bad habits begin to develop at an early age, this could harm the correct and complete brain development., so that the full potential is not achieved and this could have significant negative consequences in the long term.