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What action does insulin have? Insulin and insulin therapy: a dark forest or a harmonious system

Ecology of life. Health: Insulin is an important hormone for our health and longevity, as well as for weight control and its structure (increase in muscle mass and decrease in body fat). However, there are many myths about insulin that deceive the reader without proper scientific background. Therefore, I will try to tell you in detail and with nuances.

Insulin is an important hormone for our health and longevity, as well as for weight control and its structure (increase in muscle mass and decrease in body fat mass). However, there are many myths about insulin that deceive the reader without proper scientific background. Therefore, I will try to tell you in detail and with nuances.

So we know that insulin is a pancreatic hormone that regulates blood glucose levels. After you eat something, the carbohydrates in your food are broken down into glucose (a sugar that your cells use as fuel). Insulin helps glucose get to the liver, muscles and fat cells. When the glucose concentration decreases, the insulin level also decreases. As a rule, insulin levels are lower in the morning, because about eight hours have passed since the last meal.

Insulin is a zealous owner (“everything in the house” - no matter what and where). So if you don't have room for calories, he stacks them up anywhere. Therefore, the chronobiology of nutrition and physical activity is of great importance.

Insulin stimulates and inhibits at the same time.

It is important to understand that insulin has two types of action and its ability to inhibit certain processes is just as important as its stimulatory effect. The inhibitory function of insulin is often much more important than its activating or stimulating function. Thus, insulin is more like a traffic controller or a traffic light at a crossroads. It helps slow down and streamline movement. Without a traffic light or a traffic controller there would be a complete mess and a lot of accidents. That is, gluconeogenesis, glycolysis, proteolysis, synthesis of ketone bodies and lipolysis in the absence of insulin would take place at high speeds without any control. And it would all end with hyperglycemia, ketoacidosis and death.

For example, high insulin:

stimulates protein synthesis
inhibits the breakdown of fat
stimulates fat accumulation
inhibits the breakdown of glycogen

1. Insulin helps muscle growth. Insulin stimulates protein synthesis by activating its production by ribosomes. In addition, insulin helps transport amino acids into muscle fibers. Insulin actively transports certain amino acids into muscle cells. We're talking about BCAAs. Branched-chain amino acids are "personally" delivered by insulin to muscle cells. And this is very good if you intend to build muscle mass.

2. Insulin prevents protein catabolism. Insulin prevents muscle breakdown. While it may not sound very exciting, the anti-catabolic nature of insulin is every bit as important as its anabolic properties.

Any financially savvy person will tell you that it's not just how much money you make that matters. It also matters how much money you spend. The same is true for muscles. Every day our body synthesizes a certain amount of proteins, and at the same time destroys the old ones. Whether you manage to gain muscle mass over time or not depends on “physiological arithmetic”. To increase muscle, you must synthesize more protein than you break down in the process of catabolism.

3. Insulin activates glycogen synthesis. Insulin increases the activity of enzymes (eg, glycogen synthase) that stimulate glycogen production. This is very important as it helps to supply glucose to the muscle cells, thus improving their performance and recovery.

4. Boosting insulin helps you feel full and suppresses hunger. Insulin is one of many hormones that play a role in making you feel full. For example, protein, by stimulating insulin, contributed to a decrease in appetite. Numerous studies have shown that insulin actually suppresses appetite.

The dark side of insulin (metabolism)

1. Insulin blocks hormone receptor lipase. Insulin blocks an enzyme called hormonal receptor lipase, which is responsible for the breakdown of adipose tissue. This is obviously bad, because if the body can't break down stored fat (triglycerides) and turn it into a form that can be burned (free fatty acids), you won't lose weight.

2. Insulin reduces fat utilization. Insulin (high insulin levels) reduces the use of fat for energy. Instead, it promotes the burning of carbohydrates. Simply put, insulin "stores fat." Although this has a negative effect on our body image, this action makes sense if we remember that the main function of insulin is to get rid of excess glucose in the blood.

3. Insulin increases the synthesis of fatty acids. And FFA (free fatty acids) is a key cause of insulin resistance! Insulin increases fatty acid synthesis in the liver, which is the first step in the fat storage process.

But it also depends on the availability of excess carbohydrates - if their volume exceeds a certain level, they are either immediately burned or stored as glycogen. Without a doubt, excess insulin is the first cause of elevated levels in the body of triglycerides, fats that were previously considered relatively safe.

Pimples, dandruff and seborrhea. They did not expect? The higher the insulin - the more intense lipogenesis, the more intense lipogenesis - the higher the level of triglycerides in the blood, the higher the level of triglycerides in the blood - the more "fat" is secreted through the sebaceous glands located throughout the body, especially on the scalp and face. We are talking about hyperfunction and hypertrophy of the sebaceous glands under the action of insulin.

In people with naturally very smooth skin who have never had acne or pimples, this side effect insulin may be completely absent. Individuals with more or less oily skin, with the ability to form acne, insulin can cause severe acne, with hypertrophy of the sebaceous glands and expansion of the skin pores. Acne in women is often one of the signs of hyperandrogenism, which may be accompanied by hyperinsulinemia and dyslipidemia.

4. Insulin activates lipoprotein lipase. Insulin activates an enzyme called lipoprotein lipase. If you are familiar with medical terminology, this may at first be perceived as a positive characteristic of insulin. After all, lipase is an enzyme that breaks down fat, so why not increase its volume?

Recall that we just discussed how insulin enhances fatty acid synthesis in the liver. Once these additional fatty acids are converted to triglycerides, they are taken up by lipoproteins (eg VLDL proteins - very low density lipoproteins), released into the blood, and seek a place to store them.

So far so good as the triglycerides cannot be absorbed by the fat cells. So while you may have enough triglycerides in your blood, you won't actually store fat. until lipoprotein lipase comes into play. Once it is activated by insulin, lipoprotein lipase breaks down these triglycerides into absorbable fatty acids, which are quickly and easily absorbed by fat cells, converted back to triglycerides there, and remain in fat cells.

5. Insulin blocks the use of glycogen.

The black side of insulin (as growth hormone)

With chronically elevated insulin levels (insulin resistance), other negative aspects of insulin come to the fore. Excess insulin disrupts the normal functioning of other hormones, inhibits growth hormone. Of course, insulin is one of the engines of the full growth of children. But in adults, its excess brings premature aging closer.

1. Excess insulin destroys arteries.

Excess insulin causes clogging of the arteries because it stimulates the growth of smooth muscle tissue around the vessels. Such cell reproduction plays a very important role in the development of atherosclerosis, when there is an accumulation of cholesterol plaques, narrowing of the arteries and a decrease in blood flow. In addition, insulin interferes with the clot dissolution system by raising the level of plasminogen activator inhibitor-1. Thus, the formation of blood clots is stimulated, which clog the arteries.

2 Insulin raises blood pressure.

If you have high blood pressure, there is a 50% chance that you are insulin resistant and have too much insulin in your bloodstream. Exactly how insulin affects blood pressure is still unknown. Insulin itself has a direct vasodilating effect. At normal people the introduction of physiological doses of insulin in the absence of hypoglycemia causes vasodilation, and not an increase in blood pressure. However, under conditions of insulin resistance, hyperactivation of the sympathetic nervous system leads to the appearance of arterial hypertension due to sympathetic stimulation of the heart, blood vessels and kidneys.

3. Insulin stimulates growth cancerous tumors.

Insulin is a growth hormone, and its excess can lead to increased cell reproduction and tumors. Fat people produce more insulin, because it is the excess of insulin that causes obesity, so they are more likely than people with normal weight to develop cancerous tumors. Tall people also have increased insulin production (the taller, the more insulin), so their risk of getting cancer is higher. These are statistics and well-known facts.

On the other hand, if you reduce the production of insulin in the body, the risk of developing cancerous tumors will also decrease. In animal experiments, it was found that long, regular breaks in food also reduce the risk of developing cancerous tumors, even if the total number of calories in the diet of animals is not reduced, in other words, after these breaks they are given plenty to eat. In these experiments, it was found that infrequent meals lead to a steady and permanent decrease in blood insulin levels.

4. Hyperinsulinemia stimulates chronic inflammation.

Hyperinsulinemia stimulates the formation of arachidonic acid, which is then converted into inflammation-stimulating PG-E2 and the amount of inflammation in the body increases dramatically. Chronically high insulin levels or hyperinsulinism also causes low adiponectin levels and this is a problem as it increases insulin resistance and inflammation.

Adiponectin is an adipose tissue hormone that maintains normal insulin sensitivity, prevents the development of diabetes and the risk of cardiovascular disease decreases. Adiponectin plays an important role in energy regulation, as well as in lipid and carbohydrate metabolism, lowering glucose and lipid levels, increasing insulin sensitivity and having anti-inflammatory effects. In obese people (particularly those with abdominal obesity), the daily secretion of adiponectin during the day was found to be reduced.

Chronobiology of insulin.

To understand the proper functioning of insulin, you need to consider:

1. Basal insulin level (depends on insulin sensitivity)
2. Dietary insulin (amount and insulin index of food).
3. The number of meals and the intervals between them.

If you eat, for example, three times a day and observe the intervals between meals, then lipogenesis and lipolysis balance each other. This is a very rough graph where the green area represents lipogenesis triggered by food intake. And the blue area shows lipolysis occurring between meals and during sleep.

A high rise in insulin when eating is good. This is good because it allows you to effectively control blood sugar levels. Insulin peaks ensure the normal course of important physiological processes.

Snacking and fat burning

When eating, insulin secretion is biphasic. The first phase happens extremely quickly; In response to an increase in glucose concentration, the pancreas releases insulin in 1-2 minutes. This rapid phase of insulin release is usually completed within about 10 minutes.

This first phase has been found to be disrupted in people with impaired glucose tolerance (those people whose blood sugar rises higher than normal after eating, and their fasting blood sugar is higher, but does not have diabetes). Let's say the insulin response correlates with the content of branched chain amino acids such as leucine, valine, and isoleucine. For example, leucine stimulates the pancreas to produce insulin.

The first, fast phase, is generally absent in type 2 diabetes.

And the second phase continues as long as there is a glucose stimulus in the blood. That is, the existing insulin is released first, and additional insulin is produced (insulin is secreted by the b-cell from the precursor (precursor) - proinsulin). Restoring the rapid phase of the insulin response improves blood sugar regulation in diabetics: rapidly rising insulin levels are not a bad thing in and of themselves.

Snacking and snacking have a very negative effect on insulin regulation. In response to a snack, insulin rises in 2-3 minutes, and returns to normal in 30-40 minutes.

On the graph, the upper arrows mark the time of the start of the meal or snack. Daily fluctuations in insulin levels are displayed on the top graph, and sugar fluctuations on the bottom. As you can see, the wave of insulin after one snack (S) reaches almost the same height as after a full meal (M). But the wave of insulin after another snack (LS) is so high that it is even higher than all the others (evening-night snack!)

In experiments on mice, it was found that if they are fed every other day, they live longer and do not get sick. When mice are not fed for 24 hours in a row throughout their lives, and in the next 24 hours they are given food to satiety, then, compared to mice that are fed 3 times a day daily, they, firstly, do not lose weight by eating when there is food, secondly, they never get sick, and thirdly, they live one and a half times longer than those mice that eat regularly 3 times every day. This fact is explained simply - mice that eat less often produce less insulin than those that eat often. Please note that eating less often does not mean less, because there is no difference in the number of calories, the weight of both mice is the same.

Insulin and stress.

If there are substances that stimulate the release of insulin, then there are substances that inhibit this release. These substances include contrainsular hormones. One of the most powerful hormones are the adrenal medulla, which are mediators in the sympathetic nervous system, adrenaline and norepinephrine.

Do you know what these hormones are for? These are the hormones that save our lives. They are released during acute stress to mobilize the entire body. One of their properties is an increase in blood sugar levels, which is an important condition for the survival of the body during times of stress.

This explains stress hyperglycemia, which disappears after the disappearance of the threat to life. With a disease such as pheochromocytoma, an excess of these hormones is synthesized, which have a similar effect. Therefore, with this disease, diabetes mellitus often develops. Glucocorticoids are hormones of the adrenal cortex, the most famous representative of which is cortisol.

Insulin and aging.

Low insulin levels are associated with good health, while low insulin sensitivity is associated with poor health.

As recently stated, it seems paradoxical that reduced insulin/IGF-1 signaling prolongs life (low blood insulin), but insulin resistance leads to type 2 diabetes. The real paradox is why, in the case of mammals, low insulin levels are associated with good health and poor insulin response with poor health. The theory of the quasi-program launched by TOR provides the answer. Insulin and IGF-1 activate TOR. Thus, attenuation of insulin/IGF‑1 signaling reduces TOR activity and thus delays aging.

Insulin resistance is a manifestation of increased TOR activity, since excessively active TOR causes insulin resistance. So in both cases, increased TOR activity is to blame: is it caused by insulin or is it manifested as insulin resistance.

Low insulin is good health", and a weakened insulin signal is "bad for health." (B) With TOR, there is no paradox. An overactive TOR may result from increased insulin levels, and a decreased insulin signal may result from overactive TOR. In both cases, TOR hyperactivity is "bad for health"

Insulin sensitivity.

The higher the amount of insulin in your blood (average), the more often it is released and the longer it lasts, the worse your insulin sensitivity. The concentration of receptors on the cell surface (including insulin receptors) depends, among other things, on the level of hormones in the blood. If this level increases significantly and for a long time, then the number of receptors for the corresponding hormone decreases, i.e. in fact, there is a decrease in the sensitivity of the cell to the hormone in the blood in excess. And vice versa.

It has been confirmed that the sensitivity of tissues to insulin decreases by 40% when the body weight is exceeded by 35-40% of the norm. Insulin sensitivity, on the other hand, is a very good thing. In this case, your cells - especially muscle cells - respond perfectly to even a small release of insulin.

And, accordingly, you need very little insulin to put them into an anabolic state. So high insulin sensitivity is what we're looking for. It is insulin sensitivity that determines the ratio of fat to muscle in your body, especially when you are trying to gain or lose weight.

If you are more insulin sensitive at the time of mass gain, you will gain more muscle than fat. For example, with normal insulin sensitivity, you will gain 0.5 kg of muscle for every kg of fat, so the ratio will be 1:2. With increased sensitivity, you will be able to gain 1 kg of muscle for every kg of fat. Or even better.

Physical activity - the most important factor maintaining normal insulin sensitivity. A sedentary lifestyle and lack of strength activity cause a strong blow.

This will be of interest to you:

Muscles of morality: adductors of the thigh

The subcutaneous muscle of the neck: the secret of a young and healthy neck

Conclusion.

1. Our goal: low basal insulin levels and good insulin sensitivity.

2. This is achieved: 2-3 meals per day. Ideally two. No snacking or snacking

3. Normalization of stress levels (remove non-food insulin triggers).

4. Do not eat high-carbohydrate foods without the proper level of physical activity.

5. Compliance with at least a minimum of physical activity, reducing a sedentary lifestyle to 4-5 hours a day (no more). published

Everyone has heard of diabetes. Fortunately, many people do not have this condition. Although it often happens that the disease develops very quietly, imperceptibly, only during a routine examination or in an emergency, showing its face. Diabetes depends on the level of a certain hormone produced and absorbed by the human body. What is insulin, how it works, and what problems can be caused by its excess or deficiency, will be discussed below.

Hormones and health

The endocrine system is one of the components of the human body. Many organs produce complex substances in their composition - hormones. They are important for the quality assurance of all processes on which human life depends. One such substance is the hormone insulin. Its excess affects only the work of many organs, but also life itself, because a sharp drop or increase in the level of this substance can cause coma or even death of a person. Therefore, a certain group of people suffering from a violation of the level of this hormone carry an insulin syringe with them at all times in order to be able to give themselves a vital injection.

The hormone insulin

What is insulin? This question is of interest to those who are familiar with its excess or deficiency firsthand, and those who have not been affected by the problem of insulin imbalance. A hormone produced by the pancreas and got its name from the Latin word "insula", which means "island". This substance got its name due to the area of \u200b\u200bformation - the islets of Langerhans located in the tissues of the pancreas. At present, scientists have studied this hormone most fully, because it affects all processes occurring in all tissues and organs, although its main task is to lower blood sugar levels.

Insulin as a structure

The structure of insulin is no longer a secret for scientists. The study of this important hormone for all organs and systems began at the end of the 19th century. It is noteworthy that the insulin-producing cells of the pancreas, the islets of Langerhans, got their name from the name of a medical student who first drew attention to the accumulation of cells in the tissue of the organ of the digestive system studied under a microscope. Nearly a century had passed since 1869 before pharmaceutical industry launched the mass production of insulin preparations so that people with diabetes can significantly improve their quality of life.

The structure of insulin is a combination of two polypeptide chains consisting of amino acid residues connected by so-called disulfide bridges. The insulin molecule contains 51 amino acid residues conventionally divided into two groups - 20 under the index "A" and 30 under the index "B". Differences between human and porcine insulin, for example, are present in only one residue under the "B" index, human insulin and bovine pancreatic hormone differ in three residues of the "B" index. Therefore, natural insulin from the pancreas of these animals is one of the most common components for drugs for diabetes.

Scientific research

The interdependence of poor-quality work of the pancreas and the development of diabetes - a disease accompanied by an increase in the level of glucose in the blood and urine, was noticed by doctors for a long time. But only in 1869, 22-year-old Paul Langerhans, a medical student from Berlin, discovered groups of pancreatic cells that were previously unknown to scientists. And it was by the name of the young researcher that they got their name - the islets of Langerhans. Some time later, during experiments, scientists proved that the secret of these cells affects digestion, and its absence sharply increases the level of sugar in the blood and urine, which has a negative effect on the patient's condition.

The beginning of the 20th century was marked by the discovery by the Russian scientist Ivan Petrovich Sobolev of the dependence of carbohydrate metabolism on the activity of secretion production of the islets of Langerhans. For quite a long time, biologists deciphered the formula of this hormone in order to be able to synthesize it artificially, because there are a lot of people with diabetes, and the number of people with this disease is constantly growing.

It was only in 1958 that the sequence of amino acids from which the insulin molecule is formed was determined. For this discovery, British molecular biologist Frederick Sanger was awarded the Nobel Prize. But the spatial model of the molecule of this hormone in 1964, using the X-ray diffraction method, was determined by Dorothy Crowfoot-Hodgkin, for which she also received the highest scientific award. Insulin in the blood is one of the main indicators of human health, and its fluctuation beyond certain normative indicators is the reason for a thorough examination and a definite diagnosis.

Where is insulin produced?

In order to understand what insulin is, it is necessary to understand why a person needs a pancreas, because it is the organ related to the endocrine and digestive systems that produces this hormone.

The structure of each organ is complex, because in addition to the departments of the organ, various tissues work in it, consisting of different cells. A feature of the pancreas are the islets of Langerhans. These are special accumulations of hormone-producing cells located throughout the body of the organ, although their main location is the tail of the pancreas. In an adult, according to biologists, there are about one million such cells, and their total mass is only about 2% of the mass of the organ itself.

How is the "sweet" hormone produced?

Insulin in the blood, contained in a certain amount, is one of the indicators of health. To come to such a clear concept for a modern person, scientists needed more than a dozen years of painstaking research.

Initially, two types of cells that make up the islets of Langerhans were isolated - type A cells and type B cells. Their difference lies in the production of a secret that is different in its functional orientation. Type A cells produce glucagon, a peptide hormone that promotes the breakdown of glycogen in the liver and maintains a constant blood glucose level. Beta cells secrete insulin, a pancreatic peptide hormone that lowers glucose levels, thereby affecting all tissues and, accordingly, organs of the human or animal body. There is a clear relationship here - A-cells of the pancreas potentiate the appearance of glucose, which in turn makes B-cells work, secreting insulin, which reduces sugar levels. From the islets of Langerhans, the "sweet" hormone is produced and enters the blood in several stages. Preproinsulin, which is the precursor peptide of insulin, is synthesized on the ribosomes of the short arm of chromosome 11. This initial element consists of 4 types of amino acid residues - A-peptide, B-peptide, C-peptide and L-peptide. It enters the endoplasmic reticulum of the eukaryotic network, where the L-peptide is cleaved from it.

Thus, preproinsulin is converted into proinsulin, which penetrates the so-called Golgi apparatus. It is there that the maturation of insulin occurs: proinsulin loses its C-peptide, separating into insulin and a biologically inactive peptide residue. From the islets of Langerhans, insulin is secreted under the influence of blood glucose, which enters the B cells. There, as a result of a cycle of chemical reactions, previously secreted insulin is released from the secretory granules.

What is the role of insulin?

The action of insulin has been studied by physiologists and pathophysiologists for a long time. It is currently the most studied hormone in the human body. Insulin is important for almost all organs and tissues, participating in the vast majority of metabolic processes. A special role is assigned to the interaction of pancreatic hormone and carbohydrates.

Glucose is a derivative in the metabolism of carbohydrates and fats. It enters the B-cells of the islets of Langerhans and causes them to actively secrete insulin. This hormone performs its maximum work when transporting glucose to adipose and muscle tissues. What is insulin for metabolism and energy in the human body? It potentiates or blocks many processes, thereby affecting the work of almost all organs and systems.

Pathway of the hormone in the body

One of the most important hormones that affects all body systems is insulin. Its level in tissues and body fluids is an indicator of health status. The path that this hormone takes from production to elimination is very complex. It is mainly excreted by the kidneys and liver. But medical scientists are studying the clearance of insulin in the liver, kidneys and tissues. So in the liver, passing through the portal vein, the so-called portal system, about 60% of the insulin produced by the pancreas breaks down. The rest, and this is the remaining 35-40%, is excreted by the kidneys. If insulin is administered parenterally, then it does not pass through the portal vein, which means that the main elimination is carried out by the kidneys, which affects their performance and, if I may say so, wear and tear.

The main thing is balance!

Insulin can be called a dynamic regulator of the processes of formation and utilization of glucose. Several hormones increase blood sugar levels, for example, glucagon, somatotropin (growth hormone), adrenaline. But only insulin lowers glucose levels, and in this it is unique and extremely important. That is why it is also called hypoglycemic hormone. A characteristic indicator of certain health problems is blood sugar, which directly depends on the production of the secretion of the islets of Langerhans, because it is insulin that reduces blood glucose.

The norm of blood sugar, determined on an empty stomach in a healthy adult, is from 3.3 to 5.5 mmol / liter. Depending on how long a person has been eating food, this indicator varies between 2.7 - 8.3 mmol / liter. Scientists have found that eating provokes a jump in glucose levels several times. A long-term steady increase in the amount of sugar in the blood (hyperglycemia) indicates the development of diabetes mellitus.

Hypoglycemia - a decrease in this indicator, can cause not only coma, but also death. If the level of sugar (glucose) falls below the physiologically acceptable value, hyperglycemic (contrinsulin) hormones that release glucose are included in the work. But adrenaline and other stress hormones strongly suppress the release of insulin even against the background of elevated sugar levels.

Hypoglycemia can develop when the amount of glucose in the blood decreases due to an excess of insulin-containing drugs or due to excessive production of insulin. Hyperglycemia, on the contrary, triggers the production of insulin.

Insulin-dependent diseases

Elevated insulin provokes a decrease in blood sugar levels, which, if left untreated, can lead to hypoglycemic coma and death. Such a condition is possible with an unidentified benign neoplasm of beta cells of the islets of Langerhans in the pancreas - insulinoma. A single overdose of insulin, deliberately administered, has been used for some time in the treatment of schizophrenia to potentiate insulin shock. But the long-term administration of large doses of insulin preparations causes a symptom complex called Somogyi syndrome.

A persistent increase in blood glucose levels is called diabetes mellitus. Experts divide this disease into several types:

type 1 diabetes is based on insufficient production of insulin by pancreatic cells, insulin in type 1 diabetes is a vital drug;
type 2 diabetes is characterized by a decrease in the sensitivity threshold of insulin-dependent tissues to this hormone;
MODY-diabetes is a whole complex of genetic defects that together give a decrease in the amount of B-cell secretion of the islets of Langerhans;
gestational diabetes mellitus develops only in pregnant women, after childbirth it either disappears or is greatly reduced.

A characteristic feature of any type of this disease is not only an increase in blood glucose levels, but also a violation of all metabolic processes, which leads to serious consequences.

You have to live with diabetes!

Not so long ago, insulin-dependent diabetes mellitus was considered something that seriously impairs the patient's quality of life. But today, for such people, many devices have been developed that greatly simplify the daily routine duties to maintain health. For example, an insulin pen has become an indispensable and convenient attribute for regularly taking the required dose of insulin, and a glucometer allows you to independently control your blood sugar level without leaving your home.

Types of modern insulin preparations

People who have to accept medications with insulin, they know that the pharmaceutical industry produces them in three different positions, characterized by the duration and type of work. These are the so-called types of insulin.

Ultrashort insulins are a novelty in pharmacology. They act for only 10-15 minutes, but during this time they manage to play the role of natural insulin and start all the metabolic reactions that the body needs.
Short-acting or fast-acting insulins are taken just before a meal. such a drug begins to work 10 minutes after oral administration, and the duration of its action is a maximum of 8 hours from the moment of administration. This type is characterized by a direct dependence on the amount of active substance and the duration of its work - the larger the dose, the longer it works. Short insulin injections are administered either subcutaneously or intravenously.
Medium insulins represent the largest group of hormones. They begin to work 2-3 hours after the introduction into the body and act within 10-24 hours. Different preparations of intermediate insulin may have different peaks of activity. Often, doctors prescribe complex preparations, including short and medium insulins.
Long-acting insulins are considered basic drugs that are taken 1 time per day, and therefore are called basic. Long-acting insulin begins to work after only 4 hours, therefore, in severe forms of the disease, skipping its intake is not recommended.

The attending physician can decide which insulin to choose for a particular case of diabetes, taking into account many circumstances and the course of the disease.

What is insulin? A vital, most thoroughly studied pancreatic hormone responsible for lowering blood sugar levels and participating in almost all metabolic processes occurring in the vast majority of body tissues.

The course of such a multi-stage and complex process as metabolism is influenced by various biological active substances and hormones, including, which is produced by special islets of Langerhans-Sobolev, which are located in the thickness of the pancreas. It takes part in almost all metabolic processes in the body.

What is insulin?

Insulin is a peptide hormone, very important for normal nutrition and cell function, it is a transporter of glucose, potassium and amino acids. It is designed to regulate. Therefore, after a meal, an increase in the amount of this substance in the blood serum in response to the production of glucose is recorded.

The process of normal cellular nutrition is impossible without insulin, and this hormone is indispensable. Insulin is a protein hormone, so it cannot enter the body through the gastrointestinal tract, since it will be digested right away, like any protein.

How does insulin work?

Insulin is also responsible for energy, and in all tissues has a complex effect on metabolism. It is able to influence the activity of many enzymes.

Insulin is the only hormone that is able to reduce blood glucose levels.

Each of us has heard of this unpleasant disease, as diabetes mellitus, as well as about insulin, which is administered to patients as replacement therapy. The thing is that in patients with diabetes, insulin is either not produced at all, or does not perform its functions. In our article we will consider the question of insulin - what it is and what effect it has on our body. An exciting journey into the world of medicine awaits you.

Insulin is...

Insulin is a hormone produced by special endocrine cells called islets of Langerhans (beta cells). The pancreas of an adult has about a million islets, whose function is to produce insulin.

Insulin - what is it from the point of view of medicine? This is a hormone of protein nature that performs extremely important necessary functions in the body. It cannot enter the gastrointestinal tract from the outside, as it will be digested, like any other substance of a protein nature. A small amount of background (basal) insulin is produced daily. After eating, the body supplies it in the amount that our body needs to digest the incoming proteins, fats and carbohydrates. Let us dwell on the question of what is the effect of insulin on the body.

Functions of insulin

Insulin is responsible for maintaining and regulating carbohydrate metabolism. That is, this hormone has a complex multifaceted effect on all tissues of the body, largely due to its activating effect on many enzymes.

One of the main and best known functions of this hormone is to regulate blood glucose levels. It is required by the body constantly, because it refers to nutrients needed for cell growth and development. Insulin breaks it down to a simpler substance, facilitating its absorption into the blood. If the pancreas does not produce enough glucose, glucose does not feed the cells, but accumulates in the blood. This is fraught with an increase (hyperglycemia), which entails serious consequences.

Also, with the help of insulin, amino acids and potassium are transported.
Few people know the anabolic properties of insulin, surpassing even the effect of steroids (the latter, however, act more selectively).

Types of insulin

Distinguish types of insulin by origin and by action.

Fast-acting has an ultra-short effect on the body. This type of insulin begins its work immediately after administration, and its peak is reached after 1-1.5. Duration of action - 3-4 hours. It is administered immediately before or before a meal. Drugs with a similar effect include Novo-Rapid, Insulin Apidra and Insulin Humalog.

Short insulin has an effect within 20-30 minutes after application. After 2-3 hours, the concentration of the drug in the blood reaches its maximum point. In total, it lasts about 5-6 hours. An injection is given 15-20 minutes before meals. In this case, approximately 2-3 hours after the introduction of insulin, it is recommended to do "snacks". The time of eating should coincide with the time of maximum effect of the drug. Short-acting drugs - preparations "Humulin Regula", "Insulin Aktrapid", "Monodar Humodar".

Intermediate-acting insulins act on the body for much longer - from 12 to 16 hours. It is necessary to make 2-3 injections per day, often with an interval of 8-12 hours, since they do not begin their action immediately, but 2-3 hours after the injection. Their maximum effect is achieved after 6-8 hours. Intermediate-acting insulins - preparations "Protafan" (human insulin), "Humudar BR", "Insulin Novomix".

And finally, long-acting insulin, the maximum concentration of which is reached 2-3 days after administration, despite the fact that it begins to act after 4-6 hours. Apply it 1-2 times a day. These are drugs such as Insulin Lantus, Monodar Long, Ultralente. This group can also include the so-called "peakless" insulin. What it is? This is insulin, which does not have a pronounced effect, acts gently and unobtrusively, therefore it practically replaces the “native” insulin produced by the pancreas for a person.

Varieties of insulins

human insulin - it is an analogue of the hormone produced by our pancreas. Such insulin and its genetically engineered "brothers" are considered more advanced than other types of animal-derived insulin.

Pork hormone is similar to the above, except for one amino acid in the composition. Can cause allergic reactions.

Bovine insulin is the least similar to human insulin. Often causes allergies, as it contains a protein alien to our body. The level of insulin in the blood of a healthy person has strict limits. Let's consider them in more detail.

What should be the level of insulin in the blood?

On average, in a healthy person, the normal level of insulin in the blood on an empty stomach ranges from 2 to 28 mcU / mol. In children, it is slightly lower - from 3 to 20 units, and in pregnant women, on the contrary, it is higher - the norm is from 6 to 27 μU / mol. In the event of an unreasonable deviation of insulin from the norm (level or low), it is recommended to pay attention to your diet and lifestyle.

Increasing the level of the hormone in the blood

Elevated insulin entails the loss of almost all of it, which negatively affects the state of health. He raises arterial pressure, contributes to obesity (due to improperly transported glucose), has a carcinogenic effect and increases the risk of diabetes. If you have elevated insulin, you should pay attention to your diet, trying to eat as many foods with a low hypoglycemic index as possible (low-fat dairy products, vegetables, sweet and sour fruits, bran bread).

Decreased blood insulin

There are cases when insulin levels are low in the blood. What is it and how to treat? An excessively low amount of sugar in the blood leads to brain disorders. In this case, it is recommended to pay attention to foods that stimulate the pancreas - kefir, fresh blueberries, boiled lean meat, apples, cabbage and (the decoction is especially effective when taken on an empty stomach).

Through proper nutrition, you can normalize insulin levels and avoid complications, such as diabetes.

insulin and diabetes

There are two types of diabetes - 1 and 2. The first refers to congenital diseases and is characterized by the gradual destruction of pancreatic beta cells. If they remain less than 20%, the body ceases to cope, and replacement therapy becomes necessary for it. But when the islets are more than 20%, you may not even notice any changes in your health. Often, short and ultrashort insulin, as well as background (extended) insulin, are used in treatment.

The second type of diabetes is acquired. Beta cells with this diagnosis work "in good faith", but the action of insulin is impaired - it can no longer perform its functions, as a result of which sugar again accumulates in the blood and can cause serious complications, up to hypoglycemic coma. For its treatment, drugs are used that help restore the lost function of the hormone.

Patients desperately need insulin injections, but type 2 diabetics often do without drugs for a long time (years and even decades). True, over time, you still have to “sit down” on insulin.

Insulin treatment helps to get rid of the complications that develop when the body's need to receive it from the outside is ignored, and also helps to reduce the load on the pancreas and even contribute to the partial restoration of its beta cells.

It is believed that, having started insulin therapy, it is no longer possible to return to drugs (pills). However, you must agree, it is better to start injecting insulin earlier, if necessary, than to refuse it - in this case, serious complications cannot be avoided. Doctors say that there is a chance in the future to refuse injections for type 2 diabetes if insulin treatment was started on time. Therefore, carefully monitor your well-being, do not forget to stick to diets - they are an integral factor in good health. Remember that diabetes is not a death sentence, but a way of life.

New Research

Scientists continue to persistently look for a way to make life easier for patients with diabetes. In 2015, the United States introduced a new development - an insulin inhalation device that will replace syringes, making life easier for diabetics. This device is already available in American pharmacies by prescription.

In the same year (and again in the USA), the so-called “smart insulin” was introduced, which is injected into the body once a day, activating itself if necessary. Despite the fact that it has only been tested on animals so far and has not yet been tested on humans, it is clear that scientists made very important discoveries in early 2015. Let's hope that in the future they will delight diabetics with their discoveries.

The hormone insulin and its role in the body are closely related to the functioning of the endocrine system. It includes several endocrine glands, each of which is needed to maintain human health. When there are failures in the work of at least one of the glands, all organs suffer.

Insulin is a well-studied hormone with a peptide base, which includes several amino acids. If the level of insulin decreases or rises, then an important function of the endocrine system is disrupted - maintaining blood sugar levels.

The most impressive and scary factor that has made the hormone so "popular" is the annual increase in the number of people who are diagnosed with diabetes.

Mechanism of insulin production

The hormone is produced in the endocrine cells of the tail of the pancreas. Clusters of these cells are called islets of Langerhans in honor of the scientist who discovered them. Despite their small size, each the islet is considered a tiny organ with a complex structure. They are responsible for the release of insulin. Here is how insulin is produced:

production of preproinsulin. In the pancreas, the basis for the hormone, preproinsulin, is created.
Synthesis of the signal peptide. Together with the base, a preproinsulin conductor, a peptide, is produced, it delivers the base to the endocrine cells. There it is synthesized into proinsulin.
maturation stage. For some time, the processed components settle in the cells of the endocrine system - in the Golgi apparatus. There they mature for some time and break down into insulin and C-peptide. The activity of the pancreas is often determined by the peptide in the course of laboratory diagnostics.
connection with zinc. The produced insulin interacts with mineral ions, and when blood sugar rises, the hormone is released from beta cells and begins to lower its level.

If the level is high in the body, then the synthesis of the hormone in the pancreas decreases. Glucagon is produced in the alpha cells of the islet of Langerhans.

Action of insulin

The main action of the hormone is the regulation of metabolic processes in the body. It affects everything: the absorption of vitamins, minerals, nutrients, as well as the breakdown of other substances. Without the help of insulin, the cells will not be able to receive glucose.

Under the action of the substance, the permeability of cell membranes increases, and glucose is freely absorbed into them. In parallel, insulin converts glucose into a polysaccharide - glycogen. It serves as a natural source of energy for humans.

Hormone functions

Reduced rates

Due to stress and eating habits, insulin can not only increase, but also decrease. It is a mistake to believe that this is a normal condition that is not dangerous to health. Start the process of lowering the hormone:

fatty, rich in carbohydrates and calories food - insulin produced by the gland is not enough to assimilate incoming products. This leads to intense production of the hormone, which quickly wears out the beta cells;
chronic tendency to overeat, even healthy food in large quantities will not be useful;
lack of sleep negatively affects the production of hormones, especially if a person sleeps steadily for 4-5 hours;
overexertion, hard or dangerous work, stimulating the release of adrenaline;
functional decline immune system, infectious lesions;
a sedentary lifestyle that causes physical inactivity, in which a lot of glucose enters the blood, but it is not processed properly.

To understand exactly how insulin affects the health of a person with diabetes, you need to consider the interaction of glucose with the hormone.

Insulin and glucose levels

In a healthy person, even in a situation where food does not enter the body for a long time, the sugar level is approximately the same. Insulin continues to be produced by the pancreas in approximately the same rhythm. When a person eats, food is broken down and carbohydrates are released as glucose molecules into the blood. Here's what happens next:

The liver receives the signal and the stored hormone is released. By reacting with glucose, it lowers the level of sugar and turns it into energy.
The gland begins a new stage of insulin production in place of the spent one.
New portions of the hormone are sent to the intestines - to break down sugars that are partially processed.
The unused glucose residue is partially converted to glycogen, which goes to rest. It is contained in the muscles and liver, partially deposited in adipose tissue.
Some time after eating, sugar begins to drop. Glucagon is released into the blood, and the accumulated glycogen begins to break down into glucose, stimulating the growth of sugar.

Insulin is an essential hormone, the level of which is closely related to the daily work of the body. Its violations lead to diseases that shorten a person's life for several decades, complicating it with a host of unpleasant side effects.