The biological activity of thyroid hormones is determined by the combination of the structural features of their molecules.
All thyronin structures with hormonal activity enclose iodine in positions 3 and 5, and, conversely, all iodothyronine structures in which there is only one iodine atom in the inner benzene ring are devoid of hormonal effect.
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In the molecules of all active iodothyronines, iodine is contained in two degrees of oxidation. The biological activity of hormones is associated with the presence of iodine atoms in the 1+ oxidation state in the inner benzene ring.
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Studies have made it possible to detect and identify the only form of iodine that has biological activity.
It turned out that this is iodine in the oxidation state of ~ 1 +, that is, in a positively monovalent form. This form of iodine causes a variety of biological activity and color of all those chemical compounds in which it is present. All other forms of iodine are deprived of these properties.
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A compound of iodine and starch.
Starch is a natural polymer. Moreover, starch is a mixture of two polymers, these are (SbH10O5) p - amylose (10-20%) and amylopectin (80-90%), residues αaO glucose.
The effect of iodamylose is much higher than that of solutions of polyiodide and potassium iodide with the same composition of molecular iodine. Paradoxical fact.
Studies of polymers with sugar do not have any antimicrobial properties; they are a breeding ground for microbes. But the combination of this “nutrient medium” with an aqueous solution of iodine increases its antimicrobial effect to the maximum.
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When iodine interacts with starch, a compound of inclusion (clathrate) of the channel type is obtained. Clathrate is a complex compound, part of one ("guest molecule") is included in the crystal structure of the "host molecule". The role of the host molecule in this case is played by the amylose molecule, and the “guest” is the iodine molecule. Molecules of iodine are located in the channel of the helix in the form of chains.
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We really wanted to stop in more detail, in this section of the presentation on the biosynthesis of thyroid hormones.
Offered by our company the preparation "Mixture of blue iodine" is a biologically active iodine in oxidation state +1. This distinguishes it from preparations based on iodine salts. The drug is a form of biologically active (organic) iodine.
Biological activity is responsible, finding it in a positively monovalent form and chromaticity. Colorless compounds do not possess biological activity.
The processing of iodine salts leads to various pathologies associated with a large capture of iodine by the thyroid gland.
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It has been established that the daily intake of iodine is 150-200 mcg, in European countries up to 300 mcg, and in the USA - up to 500 mcg. Iodides with blood flow to the thyroid gland, the tissue of which has the unique ability to capture and concentrate iodide at a rate of about 2 μg / h. If the intake of iodine in the organism decreases below 100 µg / day, hyperplasia develops first, and then nontoxic goiter of the thyroid gland.
Electron microscopic studies have shown that already 30–40 s after administration, its accumulation along the periphery of the follicle lumen in the immediate vicinity of the apical part of the cell is noted. In the gastrointestinal tract, iodides are secreted by the salivary glands and gastric mucosa, where the content of iodides is 20-30 times higher than in plasma. However, in these organs, as in the mammary gland, there are no enzymes necessary for the organification of iodine.
It can be noted that the "Mixture of blue iodine" mostly gets into the liver. Where, with the help of deiodinase, monovalent iodine is cleaved from the carbohydrate and is captured and transported to the thyroid gland. And transport occurs with the help of thyrocytes.
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"Mixture blue iodine" qualitative synthesis
The cell membranes of thyrocytes, which capture iodides (1-), cannot distinguish monovalent anions from one another and are therefore capable of capturing along with iodide other anions that carry a negative charge: SCN-, CLO-4, TcO-4. If the body excessively enters these anions, their accumulation occurs in the thyroid gland and absorption of iodine is suppressed through competition. In such cases, insufficient capture of iodides by the thyroid gland leads to a decrease in their amount in this organ and, as a result, to an insufficient synthesis of thyroid hormone.
The capture of biologically active iodine by thyrocytes is of higher quality, which does not lead to inhibition of absorption.
Iodide transport through the thyrocyte membrane is an active, energy-demanding process in which iodide comes from a medium with a lower concentration (blood plasma) to a medium with a high concentration (thyroid tissue). The concentration of free iodine in the thyroid gland is 30-40 times higher than in the blood plasma.
A high concentration of biologically active iodine in MBI requires less energy to transport iodine through the thyrocyte membrane. Since it is recognizable for the thyroid gland, and represents the iodine of its own production.
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Iodine organification
It is possible that iodide transfer through the thyrocyte membrane is carried out by a specific, not yet identified protein. This assumption is supported by the fact that the process of capturing and transporting iodide is under genetic control, as well as the fact that the increase in iodine absorption by the thyroid gland under the influence of TSH occurs only after a few hours, and not immediately after exposure to the hormone.
The organification (oxidation) of iodine or tyrosine iodization in thyroglobulin. The next stage after the capture of iodine by the thyroid gland is the synthesis of thyroid hormones, which begins with the rapid fixation of iodine into the tyrosine molecule. However, before going into the thyroid gland, where iodide will be used to synthesize thyroid hormones, it must be oxidized to the active form with the help of the enzyme thyroperoxidase and hydrogen peroxide (H202).
When using preparations of biologically active iodine (MBI), this mechanism of organification is not needed. Iodine is in the oxidation state of 1+, i.e. organificated, and fully capable of iodizing a tyrosine molecule to form monoiodotyrosine (MIT) or diiodotyrosine (DIT). The thyroid peroxidase system of the thyroid gland uses every atom of iodine entering it and prevents the possible return of iodine to the bloodstream. Biologically active iodine in the liver is cleaved by deiodinase from tyrosine and enters the thyroid gland.
and the drop turns very dark blue.
