Complete renewal of the human body. The frequency of renewal of the human body

I always say that our body is magnificent and ingenious. All we need is not to interfere with his work. Well, of course, don’t feed him any poisonous crap.
By giving up poisons and starting to eat healthy food, after some time we will get absolutely healthy body, unless, of course, you had some very serious illnesses before. But my favorite scientists say that even serious illnesses can be significantly alleviated and cured over time by switching to proper nutrition.
So that's what I'm getting at.
All the cells of our body are constantly renewed, and we have, with some periodicity (each organ has its own period), completely new organs.

Leather: fastest to update outer layer skin in contact with the environment. Epidermal cells are renewed every 2-3 weeks. The deeper layers are a little slower, but on average, the full cycle of skin renewal occurs in 60-80 days. By the way, interesting information: Every year the body produces about two billion new skin cells.
But then the question arises, why do one year old child and a sixty-year-old person's skin looks completely different. There is a lot that has not been studied in our body, but for now it is believed that the skin ages due to the deterioration (over the years) of collagen production and renewal, which is still under study. On this moment It has only been established that such factors as incorrect and poor (lack of fat and lack of proteins) nutrition, as well as too aggressive influence are very significant environment. They impair the production and quality of collagen. An excess of ultraviolet radiation also negatively affects skin regeneration. But, 20-30 minutes in the sun is considered a therapeutic dose, which has a beneficial effect on many processes in the body, including skin renewal.

Covering epithelial cells stomach and intestines They come into contact with the most aggressive environment (stomach juices and enzymes that process food) and are worn out by food constantly passing through them. They are updated every 3-5 days! (what kind of deposits of “toxins and waste” can we even talk about?).

The structure of the tongue mucosa is very complex, and we will not go into details. The rate of renewal of various component cells mucous membrane of the tongue (receptors) different. To put it simply, we can say that the renewal cycle of these cells is 10-14 days.

Blood- a liquid on which our whole life depends. Every day, about half a trillion different blood cells die in the average person's body. They must die in time for new ones to be born. In the body of a healthy person the number of dead cells is equal to the number of newborns. Complete blood renewal occurs within 120-150 days.

Bronchi and lungs They also come into contact with an aggressive environment, so they renew their cells relatively quickly. The outer cells of the lungs, which are the first layer of defense against aggressors, are renewed in 2-3 weeks. The remaining cells, depending on their functions, are updated with different speeds. But in general, the body needs a little less than a year to completely renew the lung tissue.
Alveoli of the bronchi updated every 11-12 months.

Hair grow on average 1-2 cm per month. That is, after some time we have completely new hair, depending on the length.

Life cycle eyelashes and eyebrows 3-6 months.

Nails on the fingers grow at a rate of 3-4 mm per month, the cycle of complete renewal is 6 months. Toenails grow at a rate of 1-2 mm per month.

Liver, truly the most magical organ in our body. Not only does he spend his entire life cleansing us of all the garbage that we put into our bodies, but she is also a champion of regeneration. It has been established that even with the loss of 75% of its cells (in the case of surgical intervention), the liver is able to recover completely, and after 2-4 months we have its full volume.
Moreover, at the age of 30-40, it regenerates the volume even with interest - by 113%. With age, liver recovery occurs only by 90-95%.
Complete renewal of liver cells occurs in 150-180 days. It has also been established that if you completely abandon toxic foods (chemicals, medications, fried foods, sugar and alcohol), the liver will independently and completely (!) clear itself of harmful effects in 6-8 weeks.
Our health largely depends on the health of our liver. But even such a hardy organ as the liver, we (with effort) can kill. Large amounts of sugar or alcohol can cause liver irreversible consequences in the form of cirrhosis.

Kidney and spleen cells are renewed every 300-500 days.

Skeleton Our body produces hundreds of millions of new cells every day. It constantly regenerates, and in its structure it has both old and new cells. But complete cellular renewal bone structure occurs over 7-10 years. With significant imbalances in nutrition, much fewer cells are produced and of poorer quality, and as a result, over the years, we have such a problem as osteoporosis.

Cells all kinds muscle tissue completely updated within 180 days.

Heart, eyes And brain are still the least studied by scientists.

Very for a long time it was believed that heart muscles are not renewed (unlike all other muscle tissue), but recent discoveries have shown that this is a misconception, and cardiac muscle tissue is renewed in the same way as other muscles. Studies have only just begun, but according to preliminary data it is known that complete renewal of the heart muscles occurs approximately (there are no exact data yet) in 20 years. That is, 3-4 times in an average life.

It is still a mystery that lens of the eye is not updated at all, or rather, why is the lens not updated. Restored and updated only cornea cells. The update cycle is quite fast - 7-10 days. If damaged, the cornea can recover in just a day.
However, this does not change the fact that the lens cells are never renewed at all! The central part of the lens is formed in the sixth week intrauterine development fetus And for the rest of your life, new cells “grow” to the central part of the lens, which makes it thicker and less flexible, worsening the quality of focusing over the years.

The brain is a mystery of mysteries...
Brain is the most poorly understood organ of our body. Of course, this is associated with a number of objective factors. The brain of a living person is very difficult to study without causing harm to it. Experiments on people are prohibited in our country (at least officially). Therefore, research is carried out on animals and terminally ill human volunteers, which is not at all equivalent to a healthy, normally functioning person.
Until recently, it was believed that brain cells never renew themselves. In principle, things are still there. The brain that controls everything we do the most complex system called the organism, the brain, which gives signals for regeneration to all our organs, does not itself renew itself at all... Hmm.
Back in the 60s of the last century, Joseph Altman discovered neurogenesis (the birth of new neurons) in the thalamus and cerebral cortex. The scientific world, as usual, was very skeptical about this discovery and forgot about it. In the mid-80s, this discovery was “rediscovered” by another scientist, Fernando Notteboom. And again silence.

But since the late 90s of the last century, full-scale studies of our brains finally began.
Currently (during latest research) several discoveries have been made. It has already been reliably established that the hippocampus and olfactory bulb still regularly renew their cells. In birds, lower vertebrates and mammals, the rate of formation of new neurons is quite high. In adult rats, approximately 250,000 new neurons are formed and replaced within a month (this is approximately 3% of the total).
The human body also renews the cells of these parts of the brain. It has also been established that the more active the physical and brain activity, the more actively new neurons are formed in these areas. But it is still under study. We're waiting...

Over the past 20 years, science has made huge strides in studying our nutrition and how our health depends on it. We finally found out that proper nutrition. It has been reliably clarified what we need to eat and what we shouldn’t eat if we want to be healthy. But in general? What is the overall result? But it turns out that “in detail” we are updated without stopping, throughout our lives. So what makes us get sick, grow old and die?

We fly into space, think about conquering and colonizing other planets. But at the same time we know so little about our body. Scientists, both in ancient times and in modern times, have absolutely no idea why, with such a huge capacity for renewal, we grow old. Why wrinkles appear and muscle condition deteriorates. Why do we lose flexibility and our bones become brittle? Why are we going deaf and stupid... No one can still say anything intelligible.

Some say that aging is in our DNA, but this theory does not evidence base, confirming it.
Others believe that aging is inherent in our brain and psychology, that we, as it were, force ourselves to grow old and die. That aging programs are embedded in our subconscious. Also just a theory without any evidence or confirmation.
Still others (very recent theories) believe that this occurs due to the “accumulation” of certain mutations and damage in mitochondrial DNA. But they don’t know why the accumulation of these damages and mutations occurs.

That is, it turns out that, contrary to the theory of evolution of comrade Darwin, cells, renewing themselves again and again, renew a deteriorated version of themselves, instead of an improved one. A bit strange...
Optimistic “alchemists” believe that we are endowed with the elixir of youth from birth, and there is no need to look for it outside. It is within us. You just need to choose the right keys to our body and learn to use your brain correctly and fully.
And then our body will be, if not immortal, then very, very long-lived!

Let's feed our body right. We will help it a little, or rather, we will not interfere with it with all sorts of poisons, and in return it will thank us with good work and a long, HEALTHY life!

It turns out that if we feed our favorite organism correctly, then in 10-15 years we will get a completely new, and most importantly healthy body. Not fast, yes. But it's real!

Let's update! All in our hands!

Yul Ivanchey

All parts of the human body are made up of cells, of which there are about 100 trillion in the adult body. Some of these cells constantly die off, and their places are taken by new ones. For different organs and tissues of the human body, the cycle of complete renewal takes an unequal amount of time.
And for many cells of our body this period has already been determined more or less accurately.
And even if, according to your passport, your age is, for example, 35 years, then your skin may be only two weeks old, your skeleton may be 10 years old, and the lenses of your eyes are approximately the same age as you.

Skin cells

Complete replacement of epithelial cells occurs within 14 days. Skin cells form in the deep layers of the dermis, gradually come to the surface and replace old cells that die and peel off. In one year, our body produces about two billion new skin cells.

Muscle cells

tours Skeletal muscle tissue is completely renewed every 15-16 years. The rate of cell renewal is affected by a person’s age - the older we get, the slower this process occurs.

Skeleton

7-10 years is the time during which complete cellular renewal of bone tissue occurs. In the structure of the skeleton, both old and young cells function simultaneously. At the same time it is wrong unbalanced diet can negatively affect the quality of new cells, causing numerous complications. Daily bone produces hundreds of millions of new cells.

Blood cells

Complete renewal of blood cells takes from 120 to 150 days. The body of a healthy person produces as many blood cells every day as they die, and this number is equal to about 500 billion cells that have different purposes.

Stomach

Gastric epithelial cells that filter nutrients inside the body, are replaced very quickly - within only 3-5 days. This is necessary, since these cells are exposed to an extremely aggressive environment - gastric juice and enzymes responsible for food processing.

Intestines

If you don't focus on intestinal epithelial cells, which are replaced every 5 days, average age intestines will be approximately 15-16 years.

Liver

Its cells are completely renewed in just 300-500 days. It is surprising that with the loss of 75% of liver cells, it is able to regenerate its full volume in just 3-4 months. That's why healthy person You can, without much fear for your health, transplant part of your liver to someone in need - it will grow again.

Heart

For a long time it was assumed that myocardial (heart muscle tissue) cells do not renew themselves at all. However, recent studies have shown that complete renewal of the heart muscle occurs approximately once every 20 years.

Vision

The lens itself and the brain cells responsible for processing visual information, have the same age as a person. Only the cells of the cornea of ​​the eye are regenerated and renewed. At the same time, complete renewal of the cornea occurs quite quickly - the entire cycle takes 7-10 days.

Brain

The hippocampus, the area of ​​the brain that is responsible for learning and memory, and the olfactory bulb regularly renew their cells. Moreover, the higher the physical and brain activity, the more often new neurons are formed in these areas.

Numerous clinical researches showed that in the human body, used cells are replaced with new ones with a certain periodicity. Essential has a blood renewal process, during which the body is cleansed of old cells and toxins, and new ones receive the necessary amount of nutrients and oxygen.

Most doctors believe that this process takes its own time for each person, depending on individual characteristics body and age. But it has been proven that the fair sex undergoes renewal a little faster than men.

Many people ask why the body renews blood and what factors influence the rate of hematopoiesis. This will be discussed further below.

Process characteristics

In international medicine, blood renewal is called “hematopoiesis.” Its progress is 80% dependent on correct functioning bone marrow.

The process of biomaterial renewal has not yet been fully studied, world scientists are trying to study its features, so reliable and correct table hematopoiesis has not yet been compiled.

The biomaterial consists of several types of cells that perform various functions. Basically the following are subject to replacement:

• Red blood cells. The most common type of cells, they contain hemoglobin and iron. Red blood cells enter the blood from the bone marrow and are responsible for the supply and saturation of oxygen to other tissues. Doctors have found that the lifespan of red blood cells is 4 months; after this time, the cells begin to die in the liver and spleen.
• Leukocytes. The main task of these bodies is to protect the body from various viruses and pathogenic microorganisms. They prevent infection, and if malicious compounds penetrate, they detect and destroy them. There are several types of leukocytes in human blood: eosinophils (protect intestinal tract And respiratory system), neutrophils (the functioning of immune system), monocytes (fight inflammatory process), basophils (prevent the development of the allergic process).
• Platelets. They are responsible for restoring and strengthening the walls of blood vessels, activating the coagulation process when receiving cuts and injuries, and preventing blood loss. Unlike other elements, platelets live from 8 to 12 days, after which they die. In their place, new ones are formed.

What determines the update speed?

Blood renewal is a complex process that depends on various factors. Today, the theory of hematopoiesis is gaining great popularity, especially among young couples planning to conceive a child.

Numerous studies have confirmed that if a child is conceived when the biomaterial of both parents is completely renewed, the likelihood that he will be born healthy, without various pathologies, increases to 98%.

Blood in the body changes in any case, but the speed and number of replaced cells depend on physiological state human and impact external factors.

Main reasons influencing the process:

• gender identity;
• Availability chronic diseases;
• nutritional features;
• taking medications of certain pharmaceutical groups;
• Availability bad habits;
• receiving serious injuries accompanied by heavy blood loss;
• donation;
• Lifestyle.

It is impossible to say exactly how many years or months the update lasts, since it depends on the characteristics of a particular person.

In men

Recent studies have confirmed that in men this biomaterial is completely renewed every 4 years. During this period, a person becomes as strong and healthy as possible.

If a married couple is planning to conceive a baby, experts recommend waiting for this moment, as the baby will be strong, resilient and strong.

The optimal age for a man to conceive a child: 24, 28, 32 years. But it is important to remember that replacement can occur at other times. This happens if a person has been seriously injured or during donation.

Among women

Unlike representatives of the stronger sex, in women renewal occurs a little more often - once every 3 years. This is largely due to the fact that during menstruation a small amount of biomaterial is lost, as a result of which recovery is faster.

Failure of the full update cycle can occur due to termination of pregnancy (both medical and surgical), donation, or recent operations.

All these processes will affect your health and condition, so blood renewal may happen earlier. It is impossible to answer how many years later the process of hematopoiesis will begin.

Update during the menstrual cycle

During menstruation, women on average lose about 150 ml. By medical standards, this volume is quite insignificant (during a donation, a person gives about 450 ml of blood).

Doctors claim that during this natural process the blood is also renewed, but in too small quantities. However, this affects general cycle renewal, and in women it happens a little faster.

During pregnancy and childbirth

During pregnancy, the blood is practically not renewed, the process slows down.

This feature is due to the fact that the body devotes energy to the life support of the baby, and other processes are “frozen”.

The situation is completely different after the baby is born. During childbirth, women lose a large amount of blood, and heavy bleeding is also observed in the days following childbirth.

The body begins to quickly and intensively cleanse itself of the baby’s waste products, and the process of hematopoiesis is activated.

Update calculation

Many health-conscious people ask their therapists whether it is possible to calculate when blood fluid renewal will begin.

It must be taken into account that each person's renewal cycle is slightly different. Also, the period of hematopoiesis largely depends on anatomical features and the impact of external factors. If a person is a donor, his renewal will occur more often and faster, this will become an individual feature.

International medicine is of the opinion that in men and women the biomaterial is renewed in the following way:

Age dependent

The number of years lived has virtually no effect on the rate of blood replacement. But human health directly depends on age. The more significant the latter, the more stress, infections and nervous experiences a person has encountered. This directly affects your overall health.

Planning a pregnancy

IN Lately future parents began to pay great attention quality and age of blood. Many experts claim that the health and gender of the baby depend on the characteristics of the biomaterial.

1. The father's age must be divided by 4.
2. Mother's age is 3.
3. Then you need to compare the remainder of the numbers.

Whose remainder is smaller, the parent determines the future gender. If the father has less balance, a boy will be born. If the mother has a girl. When the remainders are the same, the probabilities of having a son or daughter are equal.

How to speed up the update

If necessary, the process can be accelerated artificially. Most easy way To do this, sign up as a donor. If a person donates blood once a month, the formation of new cells in him accelerates several times.

If we talk about the blood transfusion procedure, it is ineffective and will not help improve the health of the body. This technique also increases the risk of side effects..

Foods that are good for your blood

You can improve the quality of your blood and saturate it with useful microelements if you adhere to proper diet. Research has confirmed that the foods that are most beneficial for your blood are:

1. Carrots, beets. They are recommended to be consumed fresh, and juices can also be made from them.
2. Garlic. If you swallow a clove of garlic before going to bed, hematopoiesis will accelerate.
3. Sea fish. Almost all varieties contain a large amount of omega-3 acids, which helps remove cholesterol and cleanse the blood.
4. White cabbage. It is recommended to make salads based on it. A vegetable subjected to heat treatment loses its properties.
5. Apples.
6. Pomegranate.
7. Nuts. They contain a lot of iron, magnesium, potassium and various vitamins.

Some scientists are still skeptical about the theory of blood renewal and consider it false, especially when it comes to planning a child. Nevertheless, many women who calculate the gender of the child using this theory note that the results coincide with the calculations.

It is necessary to understand that this biomaterial in the body, like all other cells, is renewed in any case, but it is almost impossible to calculate the frequency of the process, since it is very complex and depends on individual characteristics.

— In our body there are short-lived cells that are quickly renewed, and there are long-lived cells that are not replaced at all. It turns out to be a very wide range: some last a lifetime, others only for a couple of days, a week or several months. We are investigating the reasons that determine such a difference in the lifespan of cells, namely, genes, the work of which can increase or shorten the period of a cell’s existence,” says Professor of Harvard Medical School and Moscow State University. Lomonosov, head of laboratories for research in the field of aging Vadim Gladyshev. The scientist reported the results obtained at a recent international conference“Ways to achieve active longevity” in Kazan, where leading researchers from all over the world gathered.

Gladyshev's Harvard team studied data on 20 types of human cells and found out: the expression (that is, the activity of work) of which genes corresponds to a long life of cells inside the body and which to a shorter life span. “We built patterns and called this model longevity signature (“longevity key.”) Auto.), explains the professor. “This algorithm allows you to see which genes need to be activated in order for cells to live longer. The next stage is the selection of conditions, substances that will change the work of the necessary genes in the required direction, that is, to prolong the life of the cell (so that, of course, it remains healthy and does not degenerate into a tumor cell. - Author).” In fact, we are talking about testing potential geroprotectors, that is, compounds, drugs that can slow down aging and prolong a person’s life, experts explain.

— By the way, in the course of such “gene testing” an important circumstance may be revealed: the same “anti-aging” compound will turn out to be useful in terms of longevity for one organ/cell type of a person and at the same time useless, or even harmful, for other cells (that is will not prolong, but even shorten their lives. Auto.), notes the scientist. “This may mean that such drugs “for old age” cannot be taken in the form of tablets or injected into the blood so that they do not reach all organs.

— Maybe it will be possible to use a method that is now used to treat certain types of cancer - injections targeted at a specific place, a specific organ?

— Yes, theoretically this is one of the possible approaches.

ONCE AND FOR LIFE

On the Internet you can find many texts and colorful videos assuring that our body is “completely renewed in 7 to 10 years.” This is complete nonsense, Professor Gladyshev shakes his head. At a minimum, because the cells of our most important organs - the control center of the entire body, that is, the brain, and the main motor, that is, the heart - are practically not renewed at all. "Neurons ( nerve cells brain) occur during embryonic development, and by the 4th to 5th month of a woman’s pregnancy, the majority of these cells are formed in the unborn baby,” explains the scientist. “After birth and until the end of a person’s life, neurons mostly just die.” Alas, new nerve cells in the brain, according to the latest scientific data, appear during life in microscopic quantities.

In a word, biology-anatomy-medicine took a turn in a spiral, and after deep research using the latest methods returned to the thesis that nerve cells practically do not recover. This means that they need to be carefully protected.

THIS WILL BE USEFUL

How to extend the life of nerve cells

1. More oxygen!

For good nutrition brain cells need a full flow of oxygen. Aerobic physical exercise helps improve it, the safest of which, for any state of health and age, is walking at a brisk pace: as quickly as possible without shortness of breath.

2. Less sweets

You, of course, remember from childhood that brain cells need glucose, but if you often feed your neurons with pure sugar from sweets and cookies, then unfavorable processes will begin that damage blood vessels in the brain. It is much safer and more beneficial to provide the brain with glucose, which is formed during the absorption of slow (complex) carbohydrates, that is: minimally processed cereals (monastic oatmeal, dark rice); wholemeal bread and pasta; vegetables It is advisable to replace confectionery products with fruits.

3. No sleep deprivation

I don’t want to add stress to you, but it has been proven that with a lack of sleep, the production of substances increases, the accumulation of which can cause inflammation and subsequent death of neurons. And during good sleep On the contrary, the brain is most actively cleared of accumulated garbage. The most valuable in terms of “cleansing” is the phase of deep slow sleep, it accounts for 15 - 20% of total duration your sleep, and ideally it should be at least 1.5 - 2 hours.

EGGS: THE CLOCK IS STILL TICKING

Like neurons, eggs are given to a woman once and for life. This means that due to natural monthly losses, the supply of female germ cells is depleted and completely depleted on average by the age of 40 to 55 years. For those who are planning to have children, but for some reason are delaying pregnancy, modern medicine suggests freezing eggs and storing them in a cryobank (in Moscow, the cost of the procedures necessary to collect female germ cells and place them in storage can reach 170-175 thousand rubles, plus about 15-17 thousand rubles per year for storage in a cryobank itself).

Another type of important and, alas, non-renewable cells is cardiomyocytes, or cells of the heart muscle (myocardium). Like neurons, they can be replenished a little at a time throughout life, but the number of newly emerging cardiomyocytes is so small that there is no need to talk seriously about heart renewal, explains Vadim Gladyshev. And this is another reason to take great care of the health of your “engine”.

DO THIS

To make the heart long-lived

Cardiologist, Candidate of Medical Sciences, chief therapist of Ilyinskaya Hospital Yaroslav Ashikhmin advises:

- Control your arterial pressure(BP): outside physical activity it should always be below 130 (“upper”) and 85 (“lower”) mmHg. If the blood pressure numbers jump above 140 and 90 mm Hg. - urgently make an appointment with a therapist or cardiologist.

- Get rid of excess weight. For healthy heart normal indicator body mass index (BMI) is considered a figure up to 25. To calculate BMI, square your height (in meters), then divide your weight (in kg) by the resulting number.

— Quit smoking and don’t abuse alcohol. In the absence of contraindications (digestive diseases, pregnancy, etc.), 1 glass of dry wine per day no more than 5 times a week for women and up to 2 glasses per day no more than 5 times a week for men is considered relatively safe.

— Try to move as much as possible: according to the latest international recommendations for heart and vascular health, at least 150 minutes of moderate physical activity (30 minutes 5 days a week) or at least 75 minutes of high-intensity physical activity (15 minutes a day 5 days a week) is required weekly ).

DOES SKIN CHANGE EASILY ONCE A MONTH? DON'T CONCERN YOURSELF

Most of the other cells in our body, some faster, some slower, are renewed in one way or another. Eg, fat cells live 7.5 - 8 years, liver cells, hepatocytes on average 327 days, epithelial cells (inner lining of the intestine) 2 - 4 days, skin cells 10 - 30 days, and the lifespan of a sperm is 2 months.

However, even here, not everything is as simple as the authors of numerous pictures and videos on the Internet make it out to be, warns Professor Gladyshev. Do not delude yourself that your liver is completely renewed every year, and all your skin easily changes once a month.

— They often simplify everything, but in life a lot happens differently: let’s say, some cells are biologically capable of renewing themselves, but in fact such a cell lives in its own organ and, if removed, it will be replaced by another cell even within a day, and if left undisturbed - can sit for 10 years and not change. It also happens that the same type of cells in one place of the body has completely changed over a period of time, but in another place it lives as if nothing had happened. What factors influence this remains largely a mystery of the body’s internal self-regulation.

PROJECT “MUSCLE PHANTOM”

— There are two known ways of cell renewal. The first is division, after which the mother cell dies and is replaced by a new, daughter cell. The second way is the transformation of stem (universal - author) cells into cells of certain tissues and organs, explains a participant in the conference “Ways to achieve active longevity”, presenter Researcher RIKEN Institute (Japan), head of the laboratory of the Kazan Federal University (KFU), candidate of sciences, geneticist Oleg Gusev. - Our muscles and other organs are surrounded by pools (clusters) of stem cells, which “turn” into specialized cells when required.

Over time, the reserves of stem cells in the body are depleted, dividing cells gradually degrade ( see further “Point-by-point question”).

— Due to these and other reasons, sarcopenia develops with age, that is, loss of muscle mass, which leads to a deterioration in the quality of life: a person becomes weaker, moves worse, and the risk of falls, bruises, and fractures increases. To save people from such problems, to actually rejuvenate muscles, we are launching a large-scale international project Japanese Institute RIKEN, Kazan Federal University and the Institute of General Genetics of the Russian Academy of Sciences “Muscle Phantom”. Moreover, it is planned that Russia will play the leading role in research.

THE MYSTERY OF THE FACIAL MUSCLES

— What exactly will scientists do?

— First of all, we will analyze the variety of muscles. It is believed that humans have only three types of muscles: cardiac (myocardium), smooth muscles and skeletal muscles. But there are more than 600 skeletal muscles alone! To this day it is not known what makes them similar and diverse. Apparently, there is some special genetic program: despite the fact that all this in general skeletal muscles, they have their own components that determine what kind of species they become.

- Why is this so important to find out?

- Remember, the famous one died recently scientist Stephen Hawking? He had a severe stage of amyotrophic lateral sclerosis ( hereditary disease nervous system which is accompanied by muscle atrophy. — Author). It is amazing that even with complete paralysis, Hawking retained his facial expressions. But the disease is hereditary, which means that the mutation is the same in all cells of the body. However, as it turned out, not all types of muscles undergo dystrophy (wasting) with age - whether in cases of illness, like Stephen’s, or in healthy older people. In particular, it turned out that eye muscles and the muscles of a person’s face are the most stable. And now it is important to understand why, for example, the muscles of the limbs become the first victims of dystrophy (with age or during illness - author), while other types of muscles do not. What's so special about them? If this is found out, then there are prospects for using gene therapy to return aging muscles to good condition. This is the goal of our project.

Comparing the results of studies in primates and humans, in different muscles and in at different ages, researchers plan to create the largest atlas of work different types muscles. And calculate the factors that influence muscle changes and super stability.

ASKING QUESTION

Why do we grow old when we renew ourselves?

“Firstly, the reserves of stem cells are depleted, and secondly, it is important to understand that cell division does not pass without a trace,” explains geneticist Oleg Gusev.- In any case, division leads to the accumulation of errors and mutations. The parent cell passes on DNA with some defects to the child cell. In addition to genes, part of the biological material from the mother cell, for example, fragments of old proteins and other unfavorable inheritance. So the new cells are already a little “old”, and each subsequent one is conditionally partially worse than the previous one, especially as a person’s age increases.

“Of course, our body has reparation tools, that is, correcting damage that occurs in the DNA of mother and daughter cells,” adds biologist Vadim Gladyshev.“However, the older the body, the slower and worse the repair mechanisms work, and more and more defects accumulate. The process of accumulation of such unfavorable changes is aging, and its external manifestations- decrepitude and diseases that develop with age. However, biologically we have no obstacles that would prevent us from intervening in the aging conveyor and slowing it down - just as we have already learned to slow down and cure many serious diseases.

The author of the article thanks the co-chairman of the organizing committee of the international conference “Ways to achieve active longevity” for his assistance. Fania Maganova And scientific supervisor conference, corresponding member of the Russian Academy of Sciences Alexey Moskalev.

HOW OLD ARE YOU?

Take your time to answer this seemingly simple question, because Swedish neurologist Jonas Friesen answered it for you: every adult is on average fifteen and a half years old. If, according to your passport, you are, for example, sixty, then the lenses of your eyes are on average 22 weeks older (!), your brain is about your age, but your skin is only two weeks old. Muscle cells of the intercostal muscles in people 37-40 years old, as it turned out, are on average 15.1 years old, and intestinal cells (except the epithelium) are 15.9 years old.

The statement wanders from one popular science book to another: our body is almost completely renewed in seven years. Old cells gradually die off, their places are taken by new ones.

Cells are indeed renewed, but no one really knows where the mythical number “seven” came from. For some cells, the renewal period is set more or less precisely, namely: 150 days for blood cells, the gradual replacement of which can be monitored after a blood transfusion, and two weeks for skin cells that appear in its deep layers, gradually migrate to the surface, and die and peel off.

Our body renews itself constantly. In one day, millions of new cells appear in it, and millions of old ones die off. Cells that come into contact with external environment. For example, skin cells are renewed on average in three weeks, and the cells of the inner walls of the intestines (which make up the smallest villi that absorb nutrients from food masses) - in 3-5 days.

Receptor cells on the surface of the tongue, which help distinguish the tastes of food, are renewed every 10 days. Blood cells - red blood cells - are renewed on average in 120 days, therefore, in order to see the picture of changes in our body, it is recommended to do this once every six months general analysis blood.

Liver cells are renewed in 300-500 days. If you give up alcohol, don’t eat fatty or spicy foods, and don’t take medications, the liver can be completely cleansed in 8 weeks. By the way, the liver is the only organ in our body that is able to fully recover after losing 75% of its tissue.

Alveoli (air sacs located at the ends of the bronchi) are renewed within one year, and cells on the surface of the lungs are renewed every 2-3 weeks.

Bone tissue is constantly renewed - bone fusion after fractures occurs precisely due to its regeneration. But in order for our skeleton to be completely renewed, it takes from 7 to 10 years.

Fingernails grow by 3-4 mm per month, and hair grows by an average of one centimeter. Hair can completely change in a few years, depending on its length. It is believed that in men, hair change occurs within three years, and in women, this cycle can reach seven or more years.

The more complex the structure of the tissue and its function, the longer the process of its regeneration. In our body, nervous tissue is considered the most complex in structure. And although previously scientists were sure that it was not restored, it has now been revealed that regenerative processes are possible in it too. The brain, the lenses of the eyes and the heart also hold many unsolved mysteries for scientists, since these organs have not yet been fully studied. At the moment, scientists believe that their regeneration process is very complex and almost impossible.

As a neurologist, Friesen's main interest, of course, is the brain. From studies conducted on animals, as well as on one patient who was dying of cancer and agreed to have a weakly radioactive isotope injected into his brain, we know that after birth, new neurons appear in only two areas - in the hippocampus and around the ventricles of the brain.
So far, the new method has measured the age of only a few areas of the brain. According to Friesen, cerebellar cells are on average 2.9 years younger than humans themselves. The cerebellum, as is known, is responsible for the coordination of movements, and this gradually improves with age in the child, so it can be assumed that by about three years the cerebellum is fully formed. The cerebral cortex is the same age as the person himself, that is, new neurons do not appear in it throughout life. The remaining parts of the brain are still being studied.

Measuring the age of individual tissues and organs is not done out of curiosity. Knowing the rate of cell turnover, we may be able to treat cataracts, obesity and some nervous diseases. In 2004, researchers from Columbia University (USA) found that when depression occurs, too few new neurons are created in the hippocampus, and some anti-depression drugs stimulate this process. Alzheimer's disease has also been linked to insufficient neurogenesis in the hippocampus. In Parkinson's disease, as far as we know, the death of old cells is not balanced by the appearance of new ones.

Knowing how often people develop new fat cells can help treat obesity. No one yet knows whether this disease is associated with an increase in the number or size of fat cells. Knowing the frequency of new liver and pancreas cells will allow us to create new methods for diagnosing and treating liver cancer and diabetes.

The question of age is very relevant muscle cells hearts. Experts believe that dying cells are replaced by fibrous connective tissue, so the heart muscle weakens over time. But there is no exact data. Friesen and his team are now working to determine the age of the heart.

Americans have learned to measure the age of the lens of the eye. His central part is formed from transparent cells in the sixth week of embryonic life and remains for life. But new cells are constantly being added around the periphery of the lens, making the lens thicker and less flexible, which affects its ability to focus images. By studying this process, we may be able to find ways to delay the onset of cataracts by five years, says Bruce Buchholz of the Livermore National Laboratory (USA), where mass spectrometry measurements are carried out on samples supplied from the University of California and Friesen's laboratory.

But if many “parts” of our body are constantly renewed and, as a result, turn out to be much younger than their owner, then some questions arise. For example, if the top layer of skin is only two weeks old, why doesn't it remain smooth and pink all its life, like a two-week-old baby? If muscles are about 15 years old, why is a 60-year-old woman less dexterous and agile than a 15-year-old girl? The reason is mitochondrial DNA. It accumulates damage faster than DNA cell nucleus. This is why the skin ages over time: mutations in the mitochondria lead to a deterioration in the quality of its important constituent material, collagen.

Based on materials from New Scientist magazine