Among the metals whose ions are part of organic compounds, an important place belongs to zinc. Biochemists have introduced it into the group of trace elements, whose content in the cell does not exceed 0.0001%. Zinc cations can be found both in animals and in plant organisms, where it is part of biologically active substances, for example, such as hormones and enzymes, nucleotides, lipids and esters. The role of zinc in the human body is diverse: it is necessary for the proper metabolism, the normal course of immune processes, and the reproductive function. In this article we will take a closer look at the properties of compounds containing the trace element zinc, as well as give examples illustrating its importance in maintaining homeostasis of the human body.
Zinc atom as a complexing agent
Most of the enzymes that provide for the reactions of cellular metabolism are complex substances and contain ions of iron, magnesium, copper, zinc. In biochemistry, they are called organometallic compounds. The role of zinc in the human body is that, being the central ion, it is part of the molecules of hormones, enzymes and other biologically active substances, for example, insulin, lactate dehydrogenase, and antiprotease blood protein. Let's consider their properties further.
Glycolysis regulation
One of the stages of energy metabolism in the cell is glycolysis - an oxygen-free breakdown of glucose - the main energy substance of the cell. It is carried out in the presence of the enzyme lactate dehydrogenase and leads to the conversion of carbohydrate to lactic acid. Excessive lactate content poisons the cytoplasm of the cell, a zinc-containing enzyme is synthesized in the cytosol to cleave this substance to harmless pyruvic acid. Its action leads to the neutralization of lactic acid in the cells of the heart muscle, nephrons and myocytes, freeing the cytoplasm from the toxin, which confirms the important role of zinc in the human body. The content of lactate dehydrogenase in the blood is used in the diagnosis of diseases accompanied by pathological increased metabolism, in particular glucose breakdown, such as cancer of the liver, stomach, lungs, inflammatory processes of the kidneys and degenerative changes in the muscles.
The role of zinc in the development of the immune system
Lymph nodes, thymus, red bone marrow, palatine tonsils produce cells that have a pronounced protective effect against bacteria, viruses, foreign proteins and toxins. The level of development of the immune system decisively affects human health and largely depends on the timely formation of protective elements: antibodies, interferons, phagocytes, lymphocytes, macrophages. As biochemical studies have established, all of the above substances and cells that fight the infectious onset are formed with the direct participation of a trace element. An important role of zinc in the human body is that it is involved in the formation of T-lymphocytes and killer cells. They carry the main load in the neutralization of pathogenic bacteria and viruses that cause such serious diseases as tuberculosis, pneumonia, immunodeficiency syndrome, etc. In addition, zinc ions activate cellular genes responsible for the timely response to stressful environmental factors and increase resistance organism to them. Thymus hormones - thymosin, thymopoietin and thymulin - also become active in the presence of complex zinc particles, which helps to strengthen immune processes.
The mechanism of the effect of trace elements on viral infection
To expand our understanding of the role zinc plays in the human body, let us consider its functions in blocking the replication of nucleic acids and the synthesis of protein molecules of viruses. The results of microbiological studies confirmed the fact of the directed antiviral effect of zinc ions on pathogens of diseases such as herpes, encephalitis, and flu. In particular, the microelement contributes to the release of various types of interferons into the blood, which helps in the early stages of the disease to stop the rapid multiplication of viral particles. In particular, this concerns the translation of pathogen proteins, which are blocked. Thus, the biological role of zinc in the human body lies in its pronounced antiviral effect, which ensures the ability of cells to withstand pathogenic agents.
How does zinc regulate human reproductive functions?
The ability to reproduce and procreate is the most important property of all types of living organisms. For the female body, zinc is necessary during pregnancy, and its deficiency is manifested in the symptoms of premenstrual syndrome: migraine, the appearance of edema and painful cramps. The trace element is most important for the proper development of the male reproductive system and the fertility of gametes - sperm. The masculine type of body formation, the normal functioning of the sex glands - the testes and prostate, the viability of sperm - this is the role of zinc in the body of a man. Zinc in the form of a complexing agent is part of the most important sex hormone - testosterone, which is responsible for the entire process of spermatogenesis, reproductive properties and male libido.
The growth of the body and its dependence on organic zinc compounds
It is known that the anterior pituitary gland produces the hormone somatotropin, which determines the physiological processes of bone growth. Along with growth hormone in the hypothalamus, insulin-like molecules are synthesized , which are polypeptides called somatomedins. They contain zinc atoms and, together with growth hormone, enter the bloodstream, affecting the processes of osteogenesis. An excess of growth factors leads to diseases such as gigantism and acromegaly (disproportionately long limbs), and a lack of hormones causes dwarfism. All the above facts confirm the decisive role of zinc in the body of a child, whose growth processes are controlled by zinc-containing hormones.
Functions of the carbonic anhydrase enzyme
In the processes of catabolism in the cells and intercellular fluid, an excessive amount of decay products accumulates: acetic aldehyde, esters, carbon dioxide. In order to avoid intoxication, carbonic anhydrase is included in the enzyme group of the body. It contains a complex zinc ion and enhances the reaction of the interaction of harmful substances with water. As a result of hydration, toxins are neutralized to compounds harmless to the cell, for example, carbonic acid. The enzyme, along with hemoglobin, is part of the red blood cells of all mammals, and not just humans. Carbonic anhydrase, which contains zinc and is found in red blood cells, activates the decomposition of toxic acid salts of carbonate acid, which accumulate in the blood due to internal respiration, to water and carbon dioxide. This fact proves the extremely important role of zinc in the life of living organisms.
Zinc-containing enzyme - insulin
The pancreas - one of the main organs of the digestive system, produces a whole arsenal of vital enzymes and hormones, one of which is insulin. It contains two protein chains that can bind to zinc ions. In this state, insulin acts on glucose in the blood plasma. It reduces its excess, which appears after the intake of carbohydrates contained in bread, potatoes, and confectionery. The hormone is produced by the islets of the Langerhans of the pancreas, and with its insufficient secretion, a person develops diabetes. An important role of zinc in the human body also lies in the fact that insulin containing it also affects the metabolism of proteins and lipids, leading to the deposition of fat in the omentum and subcutaneous fat.
What is the danger of zinc deficiency for human health?
Earlier, we established the fact of the presence of a trace element in the form of a central atom of complex organic compounds present in the molecules of various enzymes. A special place among them belongs to biologically active substances - carboxypeptidases containing zinc ions. Enzymes are part of pancreatic juice and are necessary for the normal digestion of food in the duodenum and small intestine. They also participate in the synthesis of the most important hormones that control metabolism: vasopressin, oxytocin, insulin. The effect of zinc-containing carboxypeptidases on blood coagulation mechanisms, tissue repair, and reproduction functions has been proven. Obviously, zinc deficiency affects well-being and has the following symptoms: a sharp decrease in immunity, susceptibility to depressive states, disturbances in the digestive system, and abnormalities in the development of reproductive function. All this can lead to irreversible changes in the human body.
The importance of good nutrition in the prevention of zinc deficiency
A distinctive feature of the microelement is that it is slowly absorbed by the digestive system from products of plant and animal origin: beef, milk, peanuts, pumpkin and sesame seeds. Reduces the absorption of zinc by the villi of the epithelium of the small intestine, the excessive content in the chyme of coarse fiber, folic acid and copper, calcium and cadmium ions, which are antagonists of zinc. The daily requirement of a microelement for children is from 3 to 7 mg, for women - 8 mg, for men - 11 mg. Briefly, the role of zinc in the human body can be described as follows: being in the pancreas, gonads, liver, lymphocytes and muscles, a trace element is vital for the proper course of metabolic reactions, the functioning of the human digestive, endocrine and reproductive systems.