Protective hormones are hormones that stimulate the immune system. And the hormones are pests immune system is suppressed. Perhaps the name “pest” some hormones may seem offensive, but the author did not put in this word neither condemnation nor disapproval. This is a simple statement of fact. The one who weakens the defense is a pest, isn’t it?
What is the immune system, they know everything. At least approximately, in General terms.
According to scientific immunity is the ability of the body to protect itself from foreign agents – parasites (eg – intestinal worms), microorganisms, viruses and various toxins. Protection of the body is carried out with the help of cells that absorb microorganisms (such cells are called “phagocytes”), as well as with the help of special protein substances – antibodies that act not only on microorganisms, but also on parasites, viruses and foreign proteins. Antibodies bind to an alien agent and thereby deprive it of activity, we can say: “bind”.
Immunity can be innate (hereditary) and acquired during life.
And now you have a task – name at least three organs of the immune system.
Are you thinking of? Yes, the immune system is not your respiratory system. With all clear respiratory Airways and lungs. And with digestive also clear their bodies of any listed without hesitation. But the immune system is complicated. It seems to be there, and where exactly – it is unclear.
Let us be clear on this issue, otherwise we will not be able to talk about protectors and pests.
Organs of the immune system are divided into Central and peripheral.
The Central organs include the red bone marrow and the already familiar thymus or thymus. To the peripheral – spleen, lymph nodes, tonsils and other accumulations of lymphatic (or lymphoid) tissue, for example – nodules in the small intestine, which are called “Peyer plaques”.
The main organ of the immune system is the red bone marrow, which is located in the bones. Red bone marrow is a large organ, its total weight is about 4.5 % of the total body weight (in an adult – 2.5–3 kg). Red bone marrow produces blood cells, including phagocytes with lymphocytes. What are phagocytes, you already know, these are cells that absorb and digest, that is – destroy, foreign microorganisms. Lymphocytes are the main cells of the immune system that produce protein antibodies against foreign agents, as well as by contact destroy foreign cells or their cells affected by the virus. The virus is a primitive creature. To proliferate it can not. For reproduction it is necessary to penetrate into the cell and “adjust” its reproducing structures so that the cell begins to reproduce viruses. Being inside the cell, the virus is almost invulnerable, like a soldier in DotA. In order to get to the virus, the cells of the immune system must first destroy the cell that serves as a shelter.
The immune role of the thymus gland is that here Matures a variety of lymphocytes, which are called T-lymphocytes. T-lymphocytes are formed in the bone marrow, and Mature in the thymus gland. Why nature is so arranged, science is not yet able to explain. The essence of the maturation process is that the cell has receptors that allow it to recognize foreign agents (and to communicate with them).
In the spleen, a small unpaired organ located in the left upper part of the abdominal cavity, behind the stomach, other cells of the immune system ripen.
Tonsils are located in the nasopharynx and oral cavity clusters of lymphoid tissue. This tissue got its name because lymphocytes are formed in it. All six tonsils. They are divided into paired and unpaired. The paired tonsils are Palatine tonsils, located in the recess between the soft sky and the tongue, and tubal, named so because of its location in the places of exit to the nasopharynx of the auditory tubes – the channel connecting the nasopharynx to the ear. Palatine tonsils are visible when the mouth is open.
Unpaired tonsils are pharyngeal or nasopharyngeal, which is located in the back of the pharynx, and lingual, located under the surface of the back of the tongue.
In lymph nodes, also formed by lymphoid tissue, lymphocytes are produced.
Peyer’s plaques are clusters of lymphoid tissue located primarily in the small intestine, called the ileum. In the intestine of an adult can be up to 40 Peyer plaques. Plaques are protruding from the inside into the lumen of the intestine oblong Islands, 2 to 12 cm long and about 1 cm wide.
If the tonsils are a pharyngeal immune barrier that prevents the penetration of microorganisms with inhaled air and food, then Peyer’s plaques are an intestinal immune barrier. In its structure, the plaques are similar to the tonsils.
Now you have an idea about the immune system and you can talk about hormones-defenders and hormones-pests at a high scientific and professional level (do not worry, it’s a joke – nothing abstruse further you will not meet).
Let’s start with pests that inhibit our immune system.
Cortisol, which we met in the previous Chapter, as well as all other glucocorticosteroids inhibit the activity of cells of the immune system, inhibit their maturation, and cause their death.
So much for stress hormone! Logically, everything should be the opposite. Stress hormone is supposed to protect the body from intervention, it is necessary to strengthen the defense in every way, and cortisol instead destroys the defense. Yes, even as it destroys – in different ways. Gets in all directions – the young cells Mature does not, and ripened kills. And the killing did not, does not operate normally. And after that someone will turn the tongue to say that in our body everything is arranged logically? How can there be logic! With the proper organization of the case, that is – with a reasonable device of the body, the suppression of the immune system should be absent, because to suppress the good, necessary, useful is simply stupid.
And did you know that “pests” that inhibit (weaken) the immune system, there is in the immune system? No, it’s not a joke, it’s the truth. There is a variety of lymphocytes, which are called T-suppressors. The letter “T” indicates that these cells Mature in the thymus (thymus), and the word “suppressor” is translated from Latin as “suppressive”. T-suppressors inhibit the production of antibodies and reduce the sensitivity of immune cells to foreign agents called antigens.
Why weaken the immune system? And then, that immune reactions are not always good for the body. For example – in allergic reactions or autoimmune diseases.
An allergic reaction is an inadequate immune response to the presence in the body of any harmless foreign agent, that is, one that in itself can not cause the disease. An example is pollen from plants or, say, the excrement of dust mites. As a result of increased sensitivity to this agent, called “allergen”, a process similar to inflammation develops (no wonder the allergic runny nose in its symptoms resembles a cold). The misguided immune system is no longer able to stop – the more allergens enter the body, the more pronounced the immune response. The fight goes to the bitter end, which will never come, because allergies are usually caused by allergens that are constantly present in our lives (feces of dust mites) or regularly appearing in it (pollen of plants). Allergy control comes in two ways – by limiting the maximum contact with the allergen and by suppressing unnecessary and harmful activity of the immune system.
In autoimmune (“samemanner” in Latin), diseases of the immune system perceives its own tissue as foreign agents and fights with them, that is, damage them. In autoimmune diseases, not individual organs are affected, but entire organ systems, so they are referred to as systemic diseases. And it happens that the defeat covers the whole body. The most famous (but not the most common) autoimmune disease is rheumatoid arthritis, which in everyday life is incorrectly called “rheumatism”. Rheumatism is a completely different disease, the cause of which is the infection of the body with one of the types of the bacterium Streptococcus. The most common autoimmune diseases are thyroid lesions – diffuse toxic goiter, also known as “graves ‘ disease”, and Hashimoto’s thyroiditis (inflammation of the thyroid gland, first described by a Japanese scientist named Hashimoto). Autoimmune origin may have diabetes.
All of the above diseases are very serious, with a severe course and many complications. But if at the right time the excessive activity of the immune system would be suppressed, the autoimmune or allergic disease would not have developed. So hormones, which we called “pests”, in fact, are not, because their conditional pest activity is beneficial to the body. Our body, as mentioned above, is a self-regulating system, and for any self-regulating system is characterized by the presence of limiters and counterweights.
Back to our cortisol. In small doses, that is – at a relatively low concentration in the blood, cortisol and other glucocorticosteroids have on the immune system is not depressing, and stimulating effect. The fact is that the most sensitive to the depressing effects of glucocorticosteroids are T-suppressors. They suffer in the first place, even at low concentrations of hormones, this means stimulation of the immune system. Minus on minus gives plus.
Similarly, depending on the concentration, estrogens act on the immune system and female sex hormones. In large quantities they have a depressing effect, and in small – stimulating. But the mechanism of stimulation here is different, not like cortisol. It is not due to the oppression of T-suppressors, and an increase in the production of certain types of immune cells when the level of estrogen in the blood drops below normal.
Female sex hormones have a much stronger effect on the immune system than male hormones. But both stimulate local immunity of the mucous membranes of the genital tract, at least partially protecting the body from sexually transmitted diseases.
With “pests” (after what we learned this word should be quoted) we understand. We turn to the defenders, to the stimulants of our immune system, to these heroes of the invisible front, protecting us from bacteria, viruses, atypical (that is, potentially cancer) cells and other aggressive rubbish.
Hormones of the thymus gland – thymosine, thymopoetine and thymulin – by definition can not be inhibitors of immunity, because they are produced by the body in which the maturation of the lymphocytes, namely T-lymphocytes. If the hormones of the thymus gland interfered with this process, the thymus gland would cease to be part of the immune system, because no maturation of lymphocytes in it would not occur.
All the hormones of the thymus gland are proteins. Their molecules are relatively small, we can say – small. The largest is the molecule timopoetin, which consists of 49 amino acid residues. By protein standards – a mere trifle. For example, in the molecule of hemoglobin these same residues more than 500, and if you know, then – 574!
Thymulin stimulates the maturation of T-lymphocytes, activates Mature lymphocytes, stimulates the absorption of foreign agents by immune cells, as well as stimulates the production of interferons – special proteins that are released by the cells of our body in response to the invasion of the virus. Many readers of this book the word “interferon” should be familiar – such a drug is sold in pharmacies as an antiviral and immunostimulatory agent. We will not discuss the effectiveness of pharmaceutical interferons, because we are talking about something else – about those interferons that are produced in our body.
Interferons are unique products. They are able to produce only cells affected by the virus. A noble act – a dying cell produces substances that protect other cells from viruses and stimulate the activity of the immune system. Interferons have a wide range of actions. By connecting with healthy cells, they cause changes in them that prevent the reproduction of not only the virus that has struck the “mother” cell, that is, the cell that produces interferons, but also other viruses. Actually, interferons were discovered during experiments on mice, when it became clear that the presence of one viral infection is an obstacle to infection of another, that one virus prevents the reproduction of another. The stimulating effect of interferons on the immune system is manifested in an increase in the production of substances that help immune cells to recognize antigens, as well as in an increase in the activity of enzymes that “digest” foreign proteins.
By increasing the production of interferon damaged cells, thymulin provides the body struggling with viral infection, significant assistance. For that alone timeline the order can be given.
Another hormone of the thymus gland – timopoetin, is such an important matter as the education of T-lifotsitov different specialties. In scientific terms, this process is called “differentiation”. Its essence is that when lymphocytes Mature in the thymus gland, three types are formed that differ from each other in their main functions, their main purpose. T-killers, “killer lymphocytes”, kill foreign cells, increasing the permeability of their membranes. T-helpers, “lymphocytes-helpers”, help to Mature T-killers and produce antibodies to foreign agents. T-suppressors, “lymphocytes-suppressants”, suppress the activity of other lymphocytes, thereby participating in the regulation of immunity.
Timopoetin has another function that is not related to the immune system. It blocks the transmission of impulses from nerve fibers to muscle tissues. You already understand that such a blockage benefits the body as a “counterweight”. If there are substances in the body that stimulate the transmission of nerve impulses, then there must necessarily be substances that block it.
The hormone thymosine, which we will also talk about in the next Chapter on hormones that affect metabolism, plays an important immunostimulating role in the first 15 years of human life. During this period, thymosin increases the formation of lymphocytes, and later completely “switches” to the regulation of metabolism, turns from “defender” to “engineer”.
Thyroid hormone thyroxine, which is “on the periphery”, that is – outside the gland, turns into a more active form – triiodothyronine, can be called a “universal hormone”, because it affects almost all cells of our body, and not some individual, specific target cells. Triiodothyronine is formed in the thyroid gland, but in small quantities – about 75 % of the production (that is – produced by the gland hormones) is thyroxine and only about 25 % is accounted for by triiodothyronine.
If you compare the formulas of both substances, you will see that the thyroxine molecule differs from the triiodothyronine molecule by the presence of one “excess” iodine atom. The molecule of triiodothyronine is small, so it has the ability to penetrate through cell membranes and “works” inside cells, stimulating cell metabolism. The development and differentiation of all cells in our body occur with the active participation of triiodothyronine. Therefore, we can say that triiodothyronine helps to provide the immune system with “manpower”, warriors-lymphocytes. As an added bonus, this hormone increases the activity of lymphocytes, helps them to quickly destroy “enemy” foreign cells.
Insufficient activity of the thyroid gland, manifested in a decrease in the production of thyroxine and triiodothyronine (scientifically this condition is called “hypothyroidism”), is accompanied by a decrease in the activity of the immune system. Less lymphocytes and antibodies are produced, the activity of lymphocytes is reduced. But one has only to begin to enter the patient with hypothyroidism thyroxine, as it immediately goes on well.
In the epiphysis, which we after meeting with him, it seems, has never been remembered, produced the hormone melatonin – regulator daily or, as they are called, “circadian” rhythms, cyclic fluctuations in the intensity of biological processes of the body associated with the change of day and night. Melatonin is often called “sleep hormone”, but this name is not quite true, because this hormone does not put to sleep directly, but “switches” the body from one mode to another, suppresses wakefulness, preparing the body for sleep. Like triiodothyronine, melatonin is able to penetrate into cells. Inside, it binds to special receptors located on the cell nuclei, and has an effect on cellular metabolism.
The peak of melatonin production is observed after one and a half to two hours after midnight, and during the day, as the illumination increases, hormone production decreases. Melatonin causes changes in blood levels of other biologically active substances (pituitary hormones, etc.), thereby forming a daily rhythm. This is the main, but not the only function of melatonin. Among other things, it also stimulates the production of antibodies, increases the activity of immune cells and improves their recognition of foreign agents. Melatonin also increases the production of hormones by the thymus and thyroid glands, which ultimately stimulates the immune system. Figuratively speaking, melatonin enhances the immune system by hook and by crook.
Currently, the effectiveness of the appointment of melatonin to stimulate the immune system in various diseases is being actively studied.
It would seem – enough. But no. We have not yet considered the effect of somatotropin on the immune system.
The target for somatotropin is the thymus gland, which has receptors that are sensitive to this hormone. Somatotropin has a stimulating effect on almost all stages of the process of maturation and differentiation of T-lymphocytes, starting with the engraftment of immature bone marrow cells in the thymus gland and ending with the release of Mature T-lymphocytes into the blood. We can say that in this case somatotropin behaves as a growth hormone, providing “growth” of lymphocytes.
The following hormones depress the immune system:
– cortisol, as well as all other glucocorticosteroids, and in small doses, at a relatively low concentration in the blood, they have on the immune system is not depressing, and stimulating effect;
– female sex hormones estrogens in large quantities have a depressing effect on the immune system, and in small – stimulating, but the mechanism of stimulation is different, not like cortisol; female sex hormones are much stronger effect on the immune system than men, but both stimulate the local immunity of the mucous membranes of the genital tract, at least partially protecting the body from sexually transmitted diseases;
The following hormones stimulate the immune system:
– hormones thymus – thymosin, thymopoietin and thymulin; thymulin stimulates the maturation of T-lymphocytes, activates Mature lymphocytes, stimulates the absorption of foreign agents the immune cells and stimulates the production of interferon – special proteins produced by our body cells in response to the invading virus; timopoetin provides differentiation of T-lymphocytes (and it blocks the transmission of impulses from nerve fibers to muscle tissues); thymosin plays an important immunostimulating role in the first 15 years of human life, increasing the formation of lymphocytes during this period, and later completely “switches” to the regulation of metabolism.
– thyroid hormone triiodothyronine, formed from a much weaker hormone thyroxine, helps to provide the immune system with “manpower” – lymphocytes, as well as increases the activity of lymphocytes, helps them to quickly destroy “enemy” foreign cells;
– epiphysis hormone melatonin stimulates the production of antibodies, increases the activity of immune cells and improves their recognition of foreign agents, as well as increases the production of hormones by the thymus and thyroid glands, which ultimately stimulates the immune system;
– growth hormone somatotropin, produced in the pituitary gland, has a stimulating effect on all stages of the process of maturation and differentiation of T-lymphocytes in the thymus gland and ending with the release into the blood of Mature T-lymphocytes, we can say that in relation to lymphocytes somatotropin behaves as a growth hormone, providing their “growth”.