{"id":60767,"date":"2024-09-30T10:22:13","date_gmt":"2024-09-30T10:22:13","guid":{"rendered":"https:\/\/biomedpharmajournal.org\/?p=60767"},"modified":"2024-10-09T18:46:56","modified_gmt":"2024-10-09T18:46:56","slug":"comparative-analysis-of-oxidative-metabolism-in-liver-in-different-experimental-models-of-hypothyroidism-low-iodine-diet-and-anti-thyroid-drug-methimazole","status":"publish","type":"post","link":"https:\/\/biomedpharmajournal.org\/staging\/vol17no3\/comparative-analysis-of-oxidative-metabolism-in-liver-in-different-experimental-models-of-hypothyroidism-low-iodine-diet-and-anti-thyroid-drug-methimazole\/","title":{"rendered":"Comparative Analysis of Oxidative Metabolism in Liver in Different Experimental Models of Hypothyroidism: Low Iodine Diet and Anti-Thyroid drug (Methimazole)"},"content":{"rendered":"\n

Introduction<\/strong><\/p>\n\n\n\n

About 2 billion people in the world live\nin regions with iodine deficiency. Iodine deficiency diseases prevail in the\nstructure of both endocrine pathology and pathology in general1<\/sup>,\nwhich makes thyroidology one of the most relevant areas of modern research. There are a large number of approaches\nto modeling thyroid pathology\n– surgical,\ndietary, chemical, immunological,\ngenetic, radioactive methods, etc2<\/sup>. The choice of an\nexperimental model is determined by the purpose and objective of the study to\nobtain data that really correspond to clinical conditions. It is obvious that\ncomplete or partial thyroidectomy is the most appropriate method for studying\npostoperative hypothyroidism, which is not uncommon in clinical practice. Lines\nof laboratory animals with mutations, genetically engineered modifications of the\nkey genes of the hypothalamic-pituitary-thyroid axis are ideal (if any) for\nstudying genetically determined forms of thyroid dysfunction (5% in the\nstructure of thyroid pathology)2<\/sup>. Diets\nwith low iodine content are obviously preferable for studying the effectiveness\nof iodine supplementation and developing methods for the prevention of thyroid\ninsufficiency. However, surgical models require certain skills, genetically\nmodified animal lines are difficult to access, the development of low-iodine\ndiets is a rather complicated and time-consuming procedure, radioactive methods\nrequire specially equipped laboratories. Simplicity and accessibility of\nreproduction often come to the fore when choosing an experimental model.<\/p>\n\n\n\n

The rapid effect, accessibility, reproducibility of\nthe result, water solubility, and relatively low costs have brought chemical\nmethods of reproduction of hypothyroidism to the leading positions in\nexperimental thyroidology.  Administration\nof antithyroid drugs (thyrostatics), among which the most effective are\nthiourea derivatives (thioamides) \u2013 propylthiouracil (PTU) and methimazole (MMI)\n– without\nexaggeration are among\nthe most\ncommon methods of modeling hypothyroidism. The mechanism of\ntheir action is based on the inhibition of thyroid peroxidase (TPO), as well as\nsome isoenzymes of deiodinases (PTU) and some other mechanisms that are still\nbeing studied. 3-6<\/sup><\/p>\n\n\n\n

The choice of the dose, mode of administration of\nthyrostatic drugs is crucial for obtaining results that most adequately reflect\nthe changes occurring in organs and tissues in hypothyroidism. Numerous regimes\nfor the administration of thyrostatics to experimental animals have been proposed7<\/sup>.\nWe have previously shown, that daily intragastric administration to experimental\nanimals (rats) of MMI in the dose 2.5 mg per 100 g of body weight (b.w.) for 3\nmonths allows to achieve the persistent decrease in thyroid function, as\nevidenced by a decrease in the concentration of circulating thyroid hormones\nand hypothermia, and is accompanied by the least morphological and functional\nchanges in animal organs and tissues8<\/sup>. At the same time, MMI in\ndoses of 20 and 10 mg \/ 100 g of b. w. daily for 2 weeks, along with a\npersistent decrease in thyroid function, induces the development of tissue\npathology of toxic genesis, not characteristic of hypothyroidism. The daily\nintake of 1 mg of MMI for 3 weeks was not sufficient to induce a hypothyroid\nstate and persistent hypothermia. <\/p>\n\n\n\n

However, none of the models excludes the extra thyroid\neffect of the administrated xenobiotic. There is a lot of evidences of\nextra-thyroid side effects of MMI and PTU8-13<\/sup>. In particular, it is\nreported that MMI causes damage to liver cells, changes in the redox environment\nand oxidative stress, unrelated to thyroid dysfunction9<\/sup>. The\nimmunosuppressive effect of MMI, directly related to the induction of leukocyte\napoptosis, has been shown11<\/sup>. It is known that the administration of\nboth PTU and MMI is accompanied by an increase in serum calcitonin\nconcentration due to reactive hyperplasia of thyroid C-cells14<\/sup>. In\ngeneral, there are a sufficient number of reports on the side effects of\nmethimazole, and there are evidences for the involvement of reactive oxygen\nspecies (ROS) in the mechanisms of toxicity of this anti-thyroid drug15-19<\/sup>. Given the ambiguous and conflicting data on oxidative\nstress in hypothyroidism20<\/sup>, the question arises as to the\ncontribution of different experimental conditions to the pathochemical picture\nobtained by researchers using different methods of inducing hypothyroidism.    <\/p>\n\n\n\n

In the spectrum of a wide range of methods used in\nmodern thyroidology, attention is drawn to methods based on the creation of\ndiets with low iodine content (for rodents, the iodine content is <0.02\n\u00b5g\/g)7<\/sup>, as methods that most closely reproduce the changes that\ndevelop in the body under iodine and thyroid hormone deficiency. The aim of\nthis study was to assess and juxtapose indicators oxidative metabolism in the\nliver tissue of rats fed with a low-iodine diet, and rats with MMI-induced\nhypothyroidism.<\/p>\n\n\n\n

Materials and Methods<\/strong><\/p>\n\n\n\n

Animals<\/strong><\/p>\n\n\n\n

The experiments were carried out on 112 nonlinear\nwhite male rats weighing 180-220 g in vivarium conditions with a feed and water\nad libitum<\/em> in compliance with\nDeclaration of Helsinki, ethical standards and recommendations for humane\ntreatment of laboratory animals (order of the Ministry of Healthcare of Russia\nN199 dated 1.04.2016 \u201cOn Approval of the Rules of Good Laboratory Practice\u201d).<\/p>\n\n\n\n

Experimental design<\/strong><\/p>\n\n\n\n

Low Iodine Diet<\/strong><\/p>\n\n\n\n

The animals (n=56) were divided into 4 experimental\ngroups of 14 rats each.<\/p>\n\n\n\n

Group 1 (control, euthyroid) was fed with a standard\nvivarium diet (complete dry compound feed for laboratory animals \u00abChara\u00bb,\nproduced by \u00abAssortiment-Agro\u00bb LLC, Russia). <\/p>\n\n\n\n

Group 2 (LID) was fed with a special diet with a low\niodine content 21<\/sup>. <\/p>\n\n\n\n

Group 3 (LID+KI) was fed with a low-iodine diet21<\/sup>\nwith the addition of potassium iodide in a dose that ensures the daily\nrequirement of rodents for iodine, which is 2-3 \u00b5g per 100 g of body weight7<\/sup>.\nThe purpose of introducing Group 3 (LID+KI) is to ensure that the changes\nobserved in Group 2 (LID) are caused by iodine deficiency and not by other\nreasons.<\/p>\n\n\n\n

Group 4 (LID+Iodine-Chitosan) was fed with a\nlow-iodine diet21<\/sup>, and for supplementation of iodine received\n\u201cIodine-Chitosan\u201d complex22<\/sup>, which was added to the feed at a dose\nthat provided the daily iodine requirement. \n<\/p>\n\n\n\n

The standard vivarium diet usually contains from 3 to\n7 \u00b5g of iodine per day (based on the daily intake of 20 g of feed)7<\/sup>.\nTo prepare a feed with a low iodine content, 6 kg of corn flour, 2.5 kg of\nwheat gluten, 1 kg of brewer’s yeast, 0.15 kg of NaCl and 0.15 kg of CaCO3<\/sub>\nwere thoroughly mixed according to the recipe described in the source 21<\/sup>\nin the most detail. The animals were on the described feeding for 3 months.<\/p>\n\n\n\n

 On the second\nday after the last day of the experiment blood and tissue (liver) samples were\ntaken after decapitation of animals under ether anesthesia.<\/p>\n\n\n\n

MMI-induced Hypothyroidism<\/strong><\/p>\n\n\n\n

Animals (n=56) were fed\nwith a standard vivarium diet\n(complete dry compound feed for laboratory animals \u00abChara\u00bb, produced by\n\u00abAssortiment-Agro\u00bb LLC, Russia) with free access to\nwater and divided into 4 experimental groups of\n14 rats each. <\/p>\n\n\n\n

Group 1 is a control (euthyroid).<\/p>\n\n\n\n

Group 2 (MMI): rats received MMI solution intragastrically\nat the daily single dose 2,5 mg per 100 of b. w. for three weeks.<\/p>\n\n\n\n

Group 3 (MMI + recovery period): rats received MMI\nsolution intragastrically at the daily single dose 2,5 mg per 100 of body\nweight for three weeks. After reproducing the hypothyroidism model, starting\nfrom the 22nd day of the experiment, the animals for a month received a\nstandard vivarium diet.<\/p>\n\n\n\n

Group 4 (MMI + \u201cRebA-iodine\u201d): rats received MMI\nsolution intragastrically at the daily single dose 2,5 mg per 100 of body\nweight for three weeks. After 21 days of MMI-administration animals received\nthe iodine-enriched diet for a month: the iodine-polysaccharide complex on the\nbase of steviol glycoside Rebaudioside A \u201cRebA-iodine\u201d23<\/sup> was added\nto the food at a dose providing the daily iodine requirement of rats for a\nmonth. Groups of animals were involved into the experiment in such a way that\nthe reproduction of the hypothyroidism model in Group 2 coincided with the end\nof the experiment in Group 3 and Group 4.<\/p>\n\n\n\n

 On the second\nday after the last dose rats were anesthetized by ether, blood samples were obtained\nand liver dissected out.<\/p>\n\n\n\n

Assessment of Thyroid Status<\/strong><\/p>\n\n\n\n

Thyroxine and triiodothyronine fractions (total, free\nT4 <\/sub>and T3<\/sub>) were determined in the blood serum, as well as\nthe concentration of total T3<\/sub> in methanol extracts of liver tissue\nhomogenate by the enzyme immunoassay using standard kits from AlcorBio\n(Russia).<\/p>\n\n\n\n

Assessment of Oxidative Metabolism<\/strong><\/p>\n\n\n\n

Liver homogenate was prepared in phosphate buffer\n(pH=7.45) using a mechanical Potter’s homogenizer (Teflon \u2014 glass). To remove\npartially destroyed cells and nuclei, the homogenates were centrifuged for 10\nmin at 1000 rpm. All procedures for the preparation of the homogenate and the\nisolation of subcellular fractions (differential centrifugation) were carried\nout at a temperature of 0 to +4 \u00b0 C.<\/p>\n\n\n\n

Activity of cytochrome oxidase (EC 7.1.1.9) in the\nmitochondrial fraction of liver homogenate was determined by the rate of\noxidation of dimethyl-p-phenyldiamine24<\/sup>. Succinate dehydrogenase (EC\n1.3.5.1) activity was determined by ferricyanide method, malate dehydrogenase\n(EC 1.1.1.37) \u2013 by kinetic method by the rate of f NAD+<\/sup>reduction24<\/sup>.<\/p>\n\n\n\n

Lipid peroxidation products (malondialdehyde) was\ndetermined on the base of interaction with thiobarbituric acid (TBA) to form a\ncolored complex extracted with butanol.<\/p>\n\n\n\n

The content of oxidatively modified proteins (protein carbonyls)\nwas determined by the method of R.L. Levine modified by E.E. Dubinina26-26<\/sup>.\nThe method is based on the reaction of carbonyl and imino groups of oxidized\namino acid residues with 2,4\u2013dinitrophenylhydrazine (2,4\u2013DNPH) to form\n2,4\u2013dinitrophenylhydrazones of proteins determined spectrophotometrically at a wavelength\nof 370 nm.<\/p>\n\n\n\n

Reagents and other Materials<\/strong><\/p>\n\n\n\n

LID<\/strong><\/p>\n\n\n\n

Corn flour (Jinan Jinnuoakang Biotechnology Co. Ltd, China)<\/p>\n\n\n\n

Wheat gluten (AGRANA Starke GmbH, Austria)<\/p>\n\n\n\n

Brewer\u2019s yeast (Vito-House LLC, Russia)<\/p>\n\n\n\n

\u201cIodine-Chitosan\u201d (Research Center \u201cFood technologies\u201d, Bashkir Institute of Technology and Management (Branch), Moscow State University of Technology and Management named after K. G. Razumovsky)<\/p>\n\n\n\n

MMI-induced Hypothyroidism<\/strong><\/p>\n\n\n\n

Complete dry compound feed for laboratory animals \u00abChara\u00bb (\u00abAssortiment-Agro\u00bb LLC, Russia)<\/p>\n\n\n\n

Methimazole (2-mercapto-1-methylimidazole, MMI) (Innova Laboratories TD)<\/p>\n\n\n\n

 \u201cRebA-iodine\u201d (Research Center \u201cFood technologies\u201d, Bashkir Institute of Technology and Management (Branch), Moscow State University of Technology and Management named after K. G. Razumovsky, Institute of Chemistry of the Ufa Federal Research Centre of the Russian Academy of Sciences)<\/p>\n\n\n\n

Cytochrome Oxidase Assay<\/strong><\/p>\n\n\n\n

Dimethyl-p-phenyldiamine (Angene-international Ld)<\/p>\n\n\n\n

Malate Dehydrogenase <\/strong><\/p>\n\n\n\n

NAD+<\/sup> (Sigma-Aldrich)<\/p>\n\n\n\n

Succinate Dehydrogenase<\/strong><\/p>\n\n\n\n

Potassium ferricyanide (Sisco Research Laboratories)<\/p>\n\n\n\n

Malonic Dialdehide<\/strong><\/p>\n\n\n\n

“TBA -AGATE” (LLC Agate-Med, Russia)<\/p>\n\n\n\n

 Protein Carbonyls<\/strong><\/p>\n\n\n\n

2,4-dinitrophenylhydrazine (Koehler Chemie GmbH)<\/p>\n\n\n\n

Statistical Analysis<\/strong><\/p>\n\n\n\n

Statistical analysis of quantitative data was\nperformed using the STATISTICA-12 software package by calculating mean and\nstandard deviation (M\u00b1\u03c3). The normality of the distribution of the obtained\ndata was checked using the Shapiro-Wilk criterion. In case of abnormal data\ndistribution, a nonparametric test was used to calculate\nthe median (Me), upper\nand lower\nquartiles [Q1<\/sub>-Q3<\/sub>]. The\nreliability of the differences between the groups was assessed using the\nMann-Whitney U test. The differences were considered significant at p\u22640.05.<\/p>\n\n\n\n

Results <\/strong><\/p>\n\n\n\n

Serum and Tissue Concentration of Thyroid Hormones<\/strong><\/p>\n\n\n\n

LID <\/strong><\/p>\n\n\n\n

The first stage of establishing thyroid status is determination of the level of circulating thyroid hormones. The level of total thyroxine in the blood serum of rats kept on the LID for 3 months and not receiving replacement doses of potassium iodide (Group 2) amounted only 42% of the level of the control group (Table 1). Such a pronounced decrease in the concentration of the primary thyroid hormone indicates a violation of the synthesis of thyroid hormones in the thyroid gland. The concentration of the more active form of thyroid hormones (free T3<\/sub>) in the blood serum decreased slightly – to only 92% of the control, which apparently occurs due to activation of peripheral deiodination of T4<\/sub>. At the same time, a noticeable decrease in the tissue hepatic concentration of T3<\/sub> (up to 73 % of the control) makes it possible to confidently state the development of a hypothyroidism in LID-rats.<\/p>\n\n\n\n

Table 1: Concentration of thyroid hormones in the blood serum and liver tissue of LID-rats<\/strong> (Me, [Q1<\/sub>-Q3<\/sub>,], n=14)<\/strong>.<\/p>\n\n\n\n\n\n\n\n\n
\n

Thyroid<\/strong><\/p>\n

hormones<\/strong><\/p>\n<\/td>\n

\n

Group 1<\/strong><\/p>\n

(euthyroid)<\/strong><\/p>\n<\/td>\n

\n

Group 2<\/strong><\/p>\n

(LID)<\/strong><\/p>\n<\/td>\n

\n

Group 3<\/strong><\/p>\n

(LID<\/strong>+<\/strong>KI)<\/strong><\/p>\n<\/td>\n

\n

Group 4<\/strong><\/p>\n

(LID+ Iodine-Chitosan)<\/strong><\/p>\n<\/td>\n<\/tr>\n

\n

t \u04224<\/sub>,<\/p>\n

nM\/L<\/p>\n

(blood ser.)<\/p>\n<\/td>\n

\n

57.4  [52.0; 59.1]\n<\/td>\n

\n

24.3 [20.7;29.4]\n

p=.0121<\/p>\n<\/td>\n

\n

57.0 [56.8;58.3]\n

p*=.0128<\/p>\n<\/td>\n

\n

57.6 [55.7;60.6]\n

p*=.0231<\/p>\n<\/td>\n<\/tr>\n

\n

f \u04223<\/sub>,<\/p>\n

pM\/L<\/p>\n

(blood ser.)<\/p>\n<\/td>\n

\n

5.0 [4.8;5.2]\n<\/td>\n

\n

4,6 [4.5;4.7]\n

p=.0367<\/p>\n<\/td>\n

\n

4,8 [4.8;5.1]\n<\/td>\n

\n

4.7 [4.5;5.2]\n<\/td>\n<\/tr>\n

\n

t \u04223<\/sub>, ng\/g of tissue<\/p>\n

(methanol  liver tissue extract)<\/p>\n<\/td>\n

\n

6.25 [6.1;6.5]\n<\/td>\n

\n

4,4 [4.1;4.5]\n

p=.0051<\/p>\n<\/td>\n

\n

6,2 [5.7;6.5]\n

p*=.0082<\/p>\n<\/td>\n

\n

6.1[5.1;6.9]\n

p*=.0123<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/em>Legend: p \u2013 p-Value vs group 1 (euthyroid); p*-p-Value vs group-2 (LID), only statistically significant p-values are presented<\/p>\n\n\n

MMI-hypothyroidism<\/strong><\/p>\n\n\n\n

Three-week administration of the antithyroid drug (MMI) led to a rapid and significant decrease in the level of circulating thyroid hormones (Table 2). The serum concentration of total and free thyroxine in MMI-rats (Group 2) amounted 67.4% and 66.7% of the control (euthyroid rats, p=0.0002 for both tT4 <\/sub>and fT4<\/sub>). The level of the sensitive indicator of thyroid dysfunction -total T3<\/sub> – also decreased and amounted to 75.6% of the level of control animals (p=0.0001). The administration of the iodine polysaccharide complex during the recovery period (Group 4) led to a faster normalization of the level of thyroid hormones compared with the group of animals who were for a month on the standard vivarium diet after 3 weeks MMI-administration (Group 3). This indicates that the iodine polysaccharide complex \u201cRebA-iodine\u201d possesses a specific physiological activity toward the thyroid system and can be effective in supplementing the iodine deficiency.<\/p>\n\n\n\n

Table 2: Concentration of thyroid hormones in the blood serum of MMI- rats<\/strong> (M\u00b1\u03c3, n=14)<\/strong>.<\/p>\n\n\n\n\n\n\n\n\n
\n

Thyroid<\/strong><\/p>\n

hormones<\/strong><\/p>\n<\/td>\n

\n

Group 1<\/strong><\/p>\n

(euthyroid)<\/strong><\/p>\n<\/td>\n

\n

Group 2<\/strong><\/p>\n

(MMI)<\/strong><\/p>\n<\/td>\n

\n

Group 3<\/strong><\/p>\n

(MMI+recovery period)<\/strong><\/p>\n<\/td>\n

\n

Group 4<\/strong><\/p>\n

(MMI+ RebA-iodine in recovery period )<\/strong><\/p>\n<\/td>\n<\/tr>\n

\n

t \u04224<\/sub>,<\/p>\n

nM\/L<\/p>\n

 <\/p>\n<\/td>\n

\n

76.9\u00b14.53<\/p>\n<\/td>\n

\n

51.8\u00b16.02<\/p>\n

p=.0002<\/p>\n<\/td>\n

\n

63.8\u00b15.68<\/p>\n

p=.0142<\/p>\n

p2<\/sub>=.0039<\/p>\n<\/td>\n

\n

78,5\u00b16,08<\/p>\n

p2<\/sub>=.0002<\/p>\n

p3<\/sub>=.0030<\/p>\n

 <\/p>\n<\/td>\n<\/tr>\n

\n

f \u04224<\/sub>,<\/p>\n

pM\/L<\/p>\n<\/td>\n

\n

16.2\u00b11.71<\/p>\n<\/td>\n

\n

10.8\u00b12.14<\/p>\n

p=.0002<\/p>\n<\/td>\n

\n

12.6\u00b12.11<\/p>\n

p=.0038<\/p>\n

p2<\/sub>=.0613<\/p>\n<\/td>\n

\n

  17,8\u00b10,34<\/p>\n

p2<\/sub>=.0001<\/p>\n

p3<\/sub>=.0067<\/p>\n<\/td>\n<\/tr>\n

\n

t \u04223<\/sub><\/p>\n

nM\/L<\/p>\n<\/td>\n

\n

3.12\u00b10.57<\/p>\n<\/td>\n

\n

2.36\u00b10.19<\/p>\n

p=.0001<\/p>\n<\/td>\n

\n

2.91\u00b10.41<\/p>\n

p2<\/sub>=.0012<\/p>\n<\/td>\n

\n

3,21\u00b10,34<\/p>\n

p2<\/sub>=.0001<\/p>\n

p3<\/sub>=.00671<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/em>Legend: p \u2013 p-Value vs group 1 (euthyroid); p2<\/sub>-p-Value vs group 2 (MMI), p3<\/sub>-p-Value vs group 3 (MMI+recovery period), only statistically significant p-values are presented<\/p>\n\n\n

Oxidative Metabolism <\/strong><\/p>\n\n\n\n

LID<\/strong><\/p>\n\n\n\n

 The effect of\nthyroid hormones on mitochondrial respiration, mediated by the regulation of\ngene expression and activity of Krebs cycle enzymes and various components of\nthe mitochondrial chain, is widely known27-28<\/sup>. <\/p>\n\n\n\n

The activity of the terminal link of the electron transport chain – cytochrome oxidase in the mitochondrial fraction of liver homogenate of LID-rats significantly decreased, amounting to 68.5% of the enzyme activity in euthyroid animals (p=0.0202), whereas in the group receiving additional potassium iodide, it practically did not differ from the control animals (Table 3). The mitochondrial respiratory chain is the main source of reactive oxygen species that initiate free radical oxidation. TBA reactive products (predominantly malondialdehyde) are secondary products of lipid peroxidation. Concentration of one of the indicators of the intensity of free radical oxidation \u2013 malondialdehyde in LID-rats was only 58% of the level of control euthyroid animals (p=0.0127) (Table 4). At the same time, the content of protein carbonylation products (aliphatic ketondinitrophenylhydrazones) in animals kept on a low-iodine diet was slightly higher than that in control group and amounted to 116% of the level in the euthyroid animals (p=0.0411).<\/p>\n\n\n\n

Table 3: Cytochrome oxidase activity in the mitochondrial fraction of liver homogenate of LID-rats<\/strong> (nM\/ min per mg of protein, Me, [Q1<\/sub> \u2013Q3<\/sub>], n=14)<\/strong><\/p>\n\n\n\n\n\n\n\n\n
\n

Experimental group<\/strong><\/p>\n<\/td>\n

\n

Enzyme activity<\/strong><\/p>\n<\/td>\n<\/tr>\n

\n

Group 1<\/p>\n

(euthyroid)<\/p>\n<\/td>\n

\n

165.5[161.0; 230.0]\n<\/td>\n<\/tr>\n

\n

Group 2<\/p>\n

(LID)<\/p>\n<\/td>\n

\n

113.5 [104.0;161.0]\n

p=.0202<\/p>\n<\/td>\n<\/tr>\n

\n

Group 3<\/p>\n

(LID +KI)<\/p>\n

Group 4<\/p>\n

(LID +<\/p>\n

( Iodine-Chitosan)<\/p>\n<\/td>\n

\n

163.5[112.0;229.0]\n

p*=.0456<\/p>\n

161.6 [110;221.3]\n

p*=.0487<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 Legend: p \u2013 p-Value vs  group 1 (euthyroid); p*- p-Value vs group  2 (LID), only statistically significant p-values are presented<\/p>\n\n\n

Table 4: Lipid peroxidation products (malondialdehyde) and protein carbonyls in liver of LID-rats (Me, [Q1<\/sub>-Q3<\/sub>], n=14)<\/strong><\/p>\n\n\n\n\n\n\n\n
\n

Oxidative modification products<\/strong><\/p>\n<\/td>\n

\n

Group 1<\/strong><\/p>\n

(euthyroid)<\/strong><\/p>\n<\/td>\n

\n

Group 2<\/strong><\/p>\n

(LID)<\/strong><\/p>\n<\/td>\n

\n

Group 3<\/strong><\/p>\n

(LID<\/strong>+<\/strong>KI)<\/strong><\/p>\n<\/td>\n

\n

Group 4<\/strong><\/p>\n

(LID+<\/strong><\/p>\n

Iodine-Chitosan)<\/strong><\/p>\n<\/td>\n<\/tr>\n

\n

Malondialdehyde,<\/p>\n

nM\/g of tissue<\/p>\n<\/td>\n

\n

6.7343<\/p>\n[6.2699;7.3131]\n<\/td>\n

\n

3.8922<\/p>\n[2.9257; 4.4074]\n

p=.0127<\/p>\n<\/td>\n

\n

7.7105<\/p>\n[7,2322;8.4555]\n

p*=.0182<\/p>\n<\/td>\n

\n

7.1400<\/p>\n[5,2811;8.2398]\n

p*=.0202<\/p>\n<\/td>\n<\/tr>\n

\n

Protein carbonyls,<\/p>\n

nM\/mg of protein<\/p>\n<\/td>\n

\n

3.55[3.2;3.7]\n<\/td>\n

\n

4.10[3.9;4.6]\n

p=.0411<\/p>\n<\/td>\n

\n

3.00[2.7;3.2]\n

p*=.0198<\/p>\n<\/td>\n

\n

3.20[2.8;3.5]\n

p*=.0253<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Legend: p- p-Value vs group 1; p*- p-Value vs group 2 (LID), only statistically significant p-values are presented<\/p>\n\n\n

MMI-hypothyroidism<\/strong><\/p>\n\n\n\n

The used model of MMI- hypothyroidism (Group 2) was accompanied by a significant decrease in malate dehydrogenase activity \u2013 up to 70.9% (p=0.017) with simultaneous activation succinate dehydrogenase up to 163.63% (p=0.016) of the activity of control euthyroid animals (Table 5).<\/p>\n\n\n\n

Table 5: Succinate- and Malate dehydrogenase activity in liver of  MMI-rats,  (M\u00b1\u03c3, n=14)<\/strong>.<\/p>\n\n\n\n\n\n\n\n\n\n
\n

Experimental groups<\/strong><\/p>\n<\/td>\n

\n

Succinate dehydrogenase,<\/strong><\/p>\n

nM sec<\/strong>–<\/sup><\/strong>1<\/sup><\/strong>\/g of protein<\/strong><\/p>\n<\/td>\n

\n

Malate dehydrogenase,<\/strong><\/p>\n

nM sec<\/strong>–<\/sup><\/strong>1<\/sup><\/strong>\/g of protein<\/strong><\/p>\n<\/td>\n<\/tr>\n

\n

Group 1<\/p>\n

(euthyroid)<\/p>\n<\/td>\n

\n

9,9 [8,5-11,8]\n<\/td>\n

\n

2363 [2160-2524]\n<\/td>\n<\/tr>\n

\n

Group 2<\/p>\n

(MMI)<\/p>\n<\/td>\n

\n

16,2 [14,4-17,0]\n

p=.016<\/p>\n<\/td>\n

\n

1675 [1438-1748]\n

p=0.017<\/p>\n<\/td>\n<\/tr>\n

\n

Group 3<\/p>\n

(MMI+recovery period)<\/p>\n<\/td>\n

\n

28,4 [25,3-29,7]\n

p=.028<\/p>\n

p2<\/sub>=0,032<\/p>\n<\/td>\n

\n

2211 [1868-2448]\n

p2<\/sub>=.017<\/p>\n<\/td>\n<\/tr>\n

\n

Group 4<\/p>\n

(MMI+ RebA-iodine in recovery period )<\/p>\n<\/td>\n

\n

28,0 [26,0-31,8]\n

p=.028<\/p>\n

p2<\/sub>=.016<\/p>\n<\/td>\n

\n

3212 [3048; 3341]\n

p=0.026<\/p>\n

p2<\/sub>=.024<\/p>\n

p3<\/sub>=.029<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Legend: p \u2013 p-Value vs group 1 (euthyroid); p2<\/sub>-p-Value vs group 2 (MMI), p3<\/sub>-p-Value vs group 3 (MMI+recovery period), only statistically significant p-values are presented<\/p>\n\n\n

The content of TBA-reactive products in the blood and liver tissue of rats with MMI- hypothyroidism (Table 6) increased up to 121.5% and 154.1% of the level of euthyroid animals (p=0.0016 and p=0.0001, respectively). One-month intake of RebA iodine-polysaccharide complex after 3-week administration of MMI (Group 4) promoted faster normalization of thyroid hormone concentration and oxidative metabolism than in animals receiving standard vivarium diet during the recovery period (Group 3). Such organomineral complexes, in which iodine is incorporated into plant polysaccharide matrix and being a kind of analog of the main natural sources of iodine (algae), represent promising means for correction of iodine deficiency29<\/sup>.<\/p>\n\n\n

Table 6: Lipid peroxidation products in blood plasma and liver tissue of MMI-rats,  (M\u00b1<\/strong>\u03c3<\/strong>,<\/strong> n=14)<\/strong><\/p>\n\n\n\n\n\n\n
\n

MDA<\/strong><\/p>\n<\/td>\n

\n

Experimental groups<\/strong><\/p>\n<\/td>\n<\/tr>\n

\n

Group 1<\/strong><\/p>\n

(euthyroid)<\/strong><\/p>\n<\/td>\n

\n

Group 2<\/strong><\/p>\n

(MMI)<\/strong><\/p>\n<\/td>\n

\n

Group 3<\/strong><\/p>\n

(MMI+recovery period)<\/strong><\/p>\n<\/td>\n

\n

Group 4<\/strong><\/p>\n

(MMI+ RebA-iodine in recovery period )<\/strong><\/p>\n<\/td>\n<\/tr>\n

\n

Blood plasma,<\/p>\n

\u00b5M\/L<\/p>\n<\/td>\n

\n

1,81\u00b10,08<\/p>\n<\/td>\n

\n

2,20\u00b10,14<\/p>\n

\u0440=.0016<\/p>\n<\/td>\n

\n

1,91\u00b10,11<\/p>\n

\u04402<\/sub>=0,0634<\/p>\n<\/td>\n

\n

1,83\u00b10,07<\/p>\n

\u04402<\/sub>=.0021<\/p>\n<\/td>\n<\/tr>\n

\n

Liver tissue,<\/p>\n

nM\/g of tissue<\/p>\n<\/td>\n

\n

3,51\u00b10,21<\/p>\n<\/td>\n

\n

5,41\u00b10,32<\/p>\n

\u0440=.0001<\/p>\n<\/td>\n

\n

4,31\u00b10,32<\/p>\n

\u0440=.0002<\/p>\n

\u04402<\/sub>=.0002<\/p>\n<\/td>\n

\n

3,84\u00b10,22<\/p>\n

\u0440=.0119<\/p>\n

\u04402<\/sub>=.0001<\/p>\n

\u04403<\/sub>=.0005<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Legend: p \u2013 p-Value vs group 1 (euthyroid); p2<\/sub>-p-Value vs group 2 (MMI), p3<\/sub>-p-Value vs group 3 (MMI+recovery period), only statistically significant p-values are presented<\/p>\n\n\n

Discussion<\/strong><\/p>\n\n\n\n

The significant decrease in serum thyroxine level is\nthe first indicator of developing hypothyroid changes in LID-rats. At the same\ntime, according to most authors, the development of systemic hypothyroidism can\nbe stated only by reducing the level of more active T3<\/sub>. The\nconcentration of the free T3<\/sub> in the LID-rats blood also decreased,\nbut slightly \u2013 up to 92% of the level in euthyroid animals. Maintenance of the\nmore active T3 <\/sub>level under these conditions is apparently provided\nby activation of peripheral T4<\/sub>-deiodination. Compensatory shifts are\naimed at maintaining the free form of a more active form of thyroid hormones –\ntriiodothyronine, which is often observed in the early stages of adaptation to\niodine deficiency30-32<\/sup>.  The\nmain extrathyroid pool of T4<\/sub> is contained in the blood plasma, while\nabout 2\/3 of the total T3<\/sub> is in the intracellular space. Local,\ntissue thyroid status may be relatively independent of the concentration of\nthyroid hormones in the blood33-35<\/sup>. Liver tissue demonstrates the\ngreatest independence in this regard due to presence of a powerful deiodination\nsystem and a special role in maintaining the total pool of thyroid hormones in\nthe body. Based on the above, along with the serum concentration of thyroid\nhormones, their tissue concentration is of no less interest. Despite the\nabsence of pronounced changes in the serum concentration of T3<\/sub>, the\nconcentration of the most active of thyroid hormones in methanol extracts of\nliver tissue of LID-rats decreased more significantly and amounted to 73% of\nthe control level.<\/p>\n\n\n\n

 Thus, the\ndetected shifts allow us to state the development of hypothyroidism in\nLID-rats. <\/p>\n\n\n\n

Shifts in the serum concentration of thyroid hormones\nin MMI-rats also allow us to conclude the development of a hypothyroid\ncondition, but hypothyroidism of a less pronounced severity, than that in\nLID-rats.<\/p>\n\n\n\n

A natural consequence of the revealed decrease in\nconcentration of serum and the tissue concentration of thyroid hormones is a\ndecrease in the number of occupied receptors and the intensity of thyroid\nsignaling in the target tissues.<\/p>\n\n\n\n

 Traditionally,\nthyroid-dependent metabolism in target tissues is assessed by the activity of\nenergy metabolism enzymes (tricarboxylic acid cycle enzymes, respiratory\ncytochromes)32,36<\/sup>. Taking\ninto account the above, a marked decrease in the activity of cytochrome\noxidase, detected in the liver tissue of LID-animals, and amounting to only\n68.5% of the activity in the control group, can be considered the result of a\ndecrease in the intensity of thyroid signaling, especially since in animals\ntreated in addition to in a low-iodine diet of potassium iodide, the activity\nof the enzyme almost did not differ from the activity in the group of control\nanimals. <\/p>\n\n\n\n

Cytochrome oxidase is the terminal link of the respiratory\nchain that transfers electrons from cytochrome c to oxygen, thereby directly\ndetermining the intensity of cellular aerobic metabolism. In this regard, the\ndecrease in the concentration of an indicator of the intensity of free radical\noxidation processes – malondialdehyde (MDA), can be considered as a logic\nconsequence of the decrease in the activity of one of the most powerful enzymes\nof aerobic metabolism. Along with TBA-reactive\nproducts, the determination of products of oxidative modification of proteins\nis widely used as indicators of oxidative stress. In the experimental model\nused, in parallel with the decrease in the concentration of MDA, certain increase\n(up to 116% of the control) in the level of protein carbonyl was detected. Protein\ncarbonylation products are comparatively more stable, in contrast to lipid\nperoxidation products, which have a significantly shorter half-life \u03c4 \u00bd.\nProtein carbonyls are produced at earlier stages of oxidative stress37<\/sup>.\nAn increase in the persistence of protein carbonyls may also result from a\ndecrease of activity of the cellular protease systems, the rate of protein\nrenewal, increased production of aberrant proteins in translation disorders,\nchaperone deficiency37<\/sup>. Taking into account the critical role of\nthyroid hormones in the control of protein synthesis, all of the above may\noccur as a result of a decrease in the intensity of thyroid stimulation.<\/p>\n\n\n\n

The study of the activity of Krebs cycle oxidative\nenzymes in the liver of MMI-rats revealed divergent changes – a decrease of\nactivity of malate and an increase of the activity of succinate dehydrogenases.\nThe succinate oxidation pathway is important in adaptation to hypoxia and\nhypoergosis38<\/sup>. The data obtained allow us to conclude that the used\nmodel of MMI- hypothyroidism is not accompanied by a collapse of the universal\ncompensatory reaction of mitochondria with a switch to the succinate oxidation\npathway. Simultaneously with the activation of the succinate pathway, an\nincrease in the concentration of secondary lipid peroxidation products – TBA\nreactive products – was also detected in liver tissue, as well in the blood\nserum of MMI-rats. <\/p>\n\n\n\n

Numerous sources report the increase in the concentration of MDA, as well\nas other products of free radical oxidation (protein carbonyls) in patients\nwith various forms of hypothyroidism (primary, subclinical), as well as in the\ntissues of animals with experimental hypothyroidism39-42<\/sup>.  <\/p>\n\n\n\n

The development of oxidative stress in\nhyperthyroidism is easily explained. Activation of oxidative processes and\noxygen consumption by tissues (and, consequently, the production of ROS) is one\nof the specific manifestations of the action of thyroid hormones on cellular\nmetabolism20,36<\/sup>. The development of oxidative stress was also\ndetected in various forms of hypothyroidism39-42<\/sup>, which can be\nexplained by a decrease in antioxidant defense, as well as by the formation of\na pro-oxidant environment in hypothyroid tissues. A decrease in the intensity\nof lipid metabolism, changes in the lipid composition and availability of\nsubstrates for the lipid peroxidation process can increase susceptibility to\noxidative stress and provide the increase in the intensity of free oxidation\nprocesses in hypothyroidism43<\/sup>. Undoubtedly, the severity of thyroid\ndysfunction, subtle feedback mechanisms and many other factors determine the\nsometimes-contradictory results obtained when studying the intensity of free\nradical processes in hypothyroidism. When comparing the results, we obtained,\nit is impossible not to take into account the longer duration and more\npronounced degree of suppression of thyroid function in LID-rats, compared with\nMMI-animals. At the same time, there is no doubt that the contradictory data\nobtained in the study of the oxidant status in thyroid system abnormalities is\nto some extent due to the various experimental models used. A comparative\nanalysis of changes in free radical processes in the modeling of hypothyroidism\nby thyroidectomy and administration of anti-thyroid drugs revealed the\nfollowing results. Hypothyroidism caused by thyroidectomy was accompanied by a\ndecrease in the production of ROS in the myocardium and liver, while\nhypothyroidism caused by PTU and MMI was accompanied by the development of oxidative\nstress in the same tissues44<\/sup>. \nIt is reported that pathochemical changes in liver tissue in MMI\u2013induced\nhypothyroidism develop due to damage to liver by toxic products of the CYP450<\/sub>-dependent\nbiotransformation of the drug \u2013 4,5-epoxdome, as well as products of its\nsubsequent hydrolysis – glyoxal and N-methylthiourea44-45<\/sup>. Thus, in the chemically induced hypothyroidism,\npathochemical shifts can be partly caused by the extra thyroid effects of injected\nxenobiotic.  <\/p>\n\n\n\n

 <\/strong>Chemical methods of induction of hypothyroidism,\nthe most widely used in experimental thyroidology, in a short time make it\npossible to achieve pronounced and stable changes in the thyroid system, but to\nwhat extent are these changes identical to those complex subtle mechanisms of\nmultilevel control and adaptation that are triggered in the thyroid system with\niodine deficiency and hypothyroid abnormalities of thyroid status of a\ndifferent genesis? Most researchers report activation of free radical\nprocesses, in particular, lipoperoxidation in hypothyroidism caused by MMI15-19<\/sup>,\nwhile the data obtained in the model using a low-iodine diet allow us to\nconclude that the intensity of free radical oxidation and lipoperoxidation\nprocess in iodine and thyroid hormones deficiency decreases, which, taking into\naccount the specific role of thyroid system in the regulation of oxidative\nmetabolism can be considered a natural consequence of iodine and thyroid\nhormones deficiency in target tissues.<\/p>\n\n\n\n

Conclusion<\/strong><\/p>\n\n\n\n

An appropriate experimental design is crucial for obtaining reliable data that are more close to clinical conditions. Among the wide range of methods (surgical, chemical, immunological, etc.), each of which may have its advantages and disadvantages depending on the purpose and objectives of the study, low iodine diet is the most preferable for studying iodine deficient disorders as a model that most accurately reproduces changes in target tissues in hypothyroidism caused by iodine deficiency.<\/p>\n\n\n\n

Acknowledgement<\/strong><\/p>\n\n\n\n

We sincerely\nthank the staff of The Central Scientific Laboratory of the Bashkir State\nMedical University for their assistance in this research. \n<\/strong><\/p>\n\n\n\n

Funding<\/strong> Sources<\/strong><\/p>\n\n\n\n

The author(s) received no financial\nsupport for the research, authorship, and\/or publication of this article<\/p>\n\n\n\n

Conflict of Interest<\/strong><\/p>\n\n\n\n

The authors do not have any conflict of\ninterest <\/strong><\/strong><\/p>\n\n\n\n

Ethics Approval<\/strong><\/p>\n\n\n\n

All experiments have been examined and approved by the Ethics committee of the Bashkir State Medical University. <\/strong><\/p>\n\n\n\n

Informed Consent Statement<\/strong><\/p>\n\n\n\n

Consent is not applicable.<\/p>\n\n\n\n

References<\/strong><\/p>\n\n\n\n

  1. Taylor PN, Albrecht D, Scholz A, Gutierrez-Buey G, Lazarus JH, Dayan CM, Okosieme OE. Global epidemiology of hyperthyroidism and hypothyroidism. Nat Rev Endocrinol<\/em>. 2018;14(5):301-316. doi: 10.1038\/nrendo.2018.18.  
    CrossRef<\/a><\/li>
  2. Chaulin AM, Grigorieva JV, Suvorova, GN, and Duplyakov DV. Experimental Modeling of Hypothyroidism: Principles, Methods, Several Advanced Research Directions In Cardiology. Russian Open Medical Journal<\/em>. 2021; 10(3). doi: 10.15275\/rusomj.
     CrossRef <\/a><\/li>
  3. Raby C, Lagorce JF, Jambut-Absil AC, Buxeraud J, Catanzano G. The mechanism of action of synthetic antithyroid drugs: iodine complexation during oxidation of iodide. Endocrinology<\/em>. 1990;126(3):1683\u20131691.
    CrossRef <\/a><\/li>
  4. Debasish M, Gouriprasanna R, Mugesh G. Antithyroid drugs and their Analogues: Synthesis, Structure, and mechanism of action. Acc Chem Res. 2013; 46(11): 2706\u20132715. doi: 10.1021\/ar4001229
     CrossRef <\/a><\/li>
  5. Isaia F, Aragoni M, Arca M, Demartin F, Devillanova F, Floris G et al.  Interaction of Methimazole with I2: X-ray Crystal Structure of the Charge Transfer Complex Methimazole\u2212I2. Implications for the Mechanism of Action of Methimazole-Based Antithyroid Drugs. Journal of medicinal chemistry<\/em>. 2008; 51(13): 4050-3. doi:10.1021\/jm8001857.
     CrossRef <\/a><\/li>
  6. Mondal S, Raja K, Schweizer U, Mugesh G. Chemistry and Biology in the Biosynthesis and Action of Thyroid Hormones. Ange Chem. Int Ed Engl<\/em>. 2016; 55(27):7606-7630. doi:10.1002\/anie.201601116
     CrossRef <\/a><\/li>
  7. Bianco AC, Anderson G, Forrest D, Galton VA, Gereben B, Kim BW et al. American Thyroid Association Guide to investigating thyroid hormone economy and action in rodent and cell models. Thyroid. 2014;24(1):88-168. doi:10.1089\/thy.2013.0109
     CrossRef <\/a><\/li>
  8. Kamilov F Kh, Kozlov VN, Abdullina GM, Ponomarev EE, Menshikova IA, Ganeev TI. Thyroid and Extra Thyroid Effects of Methimazole in Modeling Hypothyroidism with Different Doses of Antithyroid Drug: Morfofunctional Study. Journal of Pharmaceutical Research International.<\/em> 2022; 34(39B): 43\u201357. doi: 10.9734\/jpri\/2022\/v34i39B36247.
     CrossRef <\/a><\/li>
  9. Cano-Europa E, Blas-Valdivia V, Lopez-Galindo GE, Franco-Colin M, Pineda-Reynoso M, Hernandez-Garcia A, Ortiz-Butron R. Methimazole-induced hypothyroidism causes alteration of the REDOX environment, oxidative stress, and hepatic damage; events not caused by hypothyroidism itself. Ann Hepatology<\/em>. 2010; 9(1):80-8.
    CrossRef <\/a><\/li>
  10. Wijaya N, Ong-Ramos C. Methimazole-Induced Aplastic Anemia with Concomitant Hepatitis in a Young Filipina with Graves’ Disease. J ASEAN Fed Endocr Society<\/em>. 2019; 34(1):99-102. doi:10.15605\/jafes.034.01.16.
    CrossRef <\/a><\/li>
  11. Klatka M, Grywalska E, Surdacka A, Tarach J, Klatka J, Roli\u0144ski J. Peripheral blood lymphocyte apoptosis and its relationship with thyroid function tests in adolescents with hyperthyroidism due to Graves’ disease. Arch Med Science<\/em>. 2012; 8(5):865-73. doi: 10.5114\/aoms.2012.31618.
    CrossRef <\/a><\/li>
  12. Malboosbaf R, Azizi F. Long-Term Treatment with Antithyroid Drugs: Efficacy and Safety. Int. J Endocrinol Metab<\/em>. 2020; 18. doi: 10.5812\/ijem.101487.
     CrossRef <\/a><\/li>
  13. Wang MT, Lee WJ, Huang TY, Chu CL, Hsieh CH. Antithyroid drug-related hepatotoxicity in hyperthyroidism patients: a population-based cohort study. B J Clin Pharmacol<\/em>. 2014; 78:619\u201329.
     CrossRef <\/a><\/li>
  14. Sande CM, Tondi R, Livolsi VA. The Thyroid Pathologist Meets Therapeutic Pharmacology. Endocr Pathol<\/em>. 2023; 34:48\u201356. doi:10.1007\/s12022-023-09749-1.
     CrossRef <\/a><\/li>
  15. Shell A, Sullivan JW. Acute Kidney Injury Following Methimazole Initiation: A Case Report. J Pharm Pract<\/em>. 2018; 33: 99\u2013101.
     CrossRef <\/a><\/li>
  16. Heidari R, Niknahad H, Jamshidzadeh A, Abdoli N. Factors affecting drug-induced liver injury: Antithyroid drugs as instances. Clin Mol Hepatol<\/em>. 2014; 20: 237\u2013248.
     CrossRef <\/a><\/li>
  17. Heidari R, Niknahad H, Jamshidzadeh A, Eghbal MA, Abdoli N. An Overview on the Proposed Mechanisms of Antithyroid Drugs-Induced Liver Injury. Adv Pharm Bull<\/em>. 2015; 5: 1\u201311.<\/li>
  18. Kocak M, Akarsu E, Korkmaz H, Taysi S. The Effect of Antithyroid Drugs on Osteopontin and Oxidative Stress in Graves\u2019 Disease. Acta Endocrinol<\/em>. 2019; 15: 221\u2013224
     CrossRef <\/a><\/li>
  19. Girolami F, Candellone A, Jarriyawattanachaikul W, Giorgia, Meineri Nebbia C, Badino P. Protective Effect of Natural Antioxidant Compounds on Methimazole Induced Oxidative Stress in a Feline Kidney Epithelial Cell Line (CRFK). Veterinary Sciences<\/em>. 2021; 8: 220. doi: 10.3390\/vetsci8100220.
     CrossRef <\/a><\/li>
  20. Nanda N. Oxidative stress in hypothyroidism. International Journal of Clinical and Experimental Physiology<\/em>. 2016; 3(1):4. doi:10.4103\/2348-8093.180013.
     CrossRef <\/a><\/li>
  21. Pedraza PE, Obregon MJ, Escobar-Morreale HF, del Rey FE, de Escobar GM. Mechanism of adaptation to Iodine deficiency in Rats: Thyroid status is tissue specific. Endocrinology<\/em>. 2006;147(5):2098-2108.
     CrossRef <\/a><\/li>
  22. Mamtsev AN, Baimatov VN, Kamilov FKh, Ponomarev EE, Nesterova AM, Vasiliev LV.  at all.  Food supplement for prevention of iodine deficiency and the method of its producing.  Patent Russia, no. RU 2380984C1, 2010.<\/li>
  23. Kamilov F Kh, Konkina IG, Murinov Yu I, Ivanov SP, Ivanova GV,  A.N, Kuznetsova EV. at all. Method for producing iodine-containing dietary food supplement.  Patent Russia, no. RU 2717045C1, 2020.<\/li>
  24. Prokhorova \u041cI. Methods of biochemical research (lipid and energy metabolism<\/em>). Leningrad: Leningrad University Press;1986 [In Russian].<\/li>
  25. Dubinina EE, Gavrovskaya SV, Kuzmich EV, Leonova NV, Morozova MG, Kovrugina SV et al. Oxidative modification of proteins: oxidation of tryptophan and production of dityrosine in purified proteins using Fenton’s system. Biochemistry (Mosc)<\/em>. 2002; 67(3):413\u2013421. doi:10.1023\/a:1014840617890
     CrossRef <\/a><\/li>
  26. Fomina \u041c\u0410, Abalenihina YuV, Fomina NB, Terentieva AA. Method of complex evaluation of products of oxidative modification of proteins in tissues and biological fluids. Methodical recommendations<\/em>. Ryazan, Russia: Editorial and Publishing Department of Ryazan State Medical University; 2014 [In Russian].<\/li>
  27. Harper ME, Ballantyne JS, Leach M, Brand MD. Effects of thyroid hormones on oxidative phosphorylation. Biochem Soc Trans<\/em>. 1993; 21(3):785\u2013792.
     CrossRef <\/a><\/li>
  28. Sheehan TE, Kumar PA, Hood DA. Tissue-specific regulation of cytochrome c oxidase subunit expression by thyroid hormone. Am J Physiol Endocrinol Metab<\/em>. 2004; 286(6): 968-974. doi:10.1152\/ajpendo.00478.2003.
     CrossRef <\/a><\/li>
  29. Kamilov F Kh., Konkina IG, Kozlov VN, Ganeev TI, Badykova LA, Kryachko AN. Evaluation of the nanosize and stability of aqueous dispersions of iodine-containing conjugates based on carriers of plant origin, promising for iodine enrichment of foods. Voprosy pitaniia<\/em>. 2022; 91 (6): 110\u20137. doi:10.33029\/0042-8833-2022-91-6-110-117 [in Russian]
     CrossRef <\/a><\/li>
  30. Obregon MJ, del Rey FE, Escobar GM. The Effects of Iodine Deficiency on Thyroid Hormone Deiodination. Thyroid: official journal of the American Thyroid Association. 2005; 15: 917-29. doi:10.1089\/thy.2005.15.917.
    CrossRef <\/a><\/li>
  31. Del Rey FE, Ona CR, Bernal J, Obregon MJ, Escobar GM. Generalized deficiency of 3,5,3′-triiodo-L-thyronine (T3) in tissues from rats on a low iodine intake, despite normal circulating T3 levels. Acta Endocrinol (Copenh<\/em>).1989;120(4):490-498. doi:10.1530\/acta.0.1200490
     CrossRef <\/a><\/li>
  32. Pedraza P, Obregon MJ, Escobar-Morreale FH, del Rey FE, Escobar GM. Mechanism of adaptation to iodine deficiency in Rats: Thyroid status is tissue specific. Endocrinology<\/em>. 2006;147(5):2098-2108.
    CrossRef <\/a><\/li>
  33. Chen Z, Meima ME, Peeters RP, Visser WE. Thyroid Hormone Transporters in Pregnancy and Fetal Development. International Journal of Molecular Sciences.<\/em> 2022; 23(23):15113. doi:10.3390\/ijms232315113
     CrossRef <\/a><\/li>
  34. Luongo C, Dentice M, Salvatore D. Deiodinases and their intricate role in thyroid hormone homeostasis. Nat Rev Endocrinol<\/em>. 2019; 15: 479\u2013488. doi:10.1038\/s41574-019-0218-2
     CrossRef<\/a> <\/li>
  35. Bianco AC, Dumitrescu A, Gereben B, Ribeiro MO, Fonseca TL, Fernandes G W et al. Paradigms of Dynamic Control of Thyroid Hormone Signaling. Endocrine reviews<\/em>. 2019; 40(4):1000\u20131047. doi:10.1210\/er.2018-00275
     CrossRef <\/a><\/li>
  36. Flores-Morales A, Gullberg H, Fernandez L, Stahlberg N, Lee N, Venstrom B et al. Patterns of Liver Gene Expression Governed by TR\u03b2. Molecular Endocrinology<\/em>. 2002; 16: 1257-1268. doi:10.1210\/me.16.6.1257.
    CrossRef <\/a><\/li>
  37. Cai Z, Yan L-J. Protein Oxidative Modifications: Beneficial Roles in Disease and Health. Journal of biochemical and pharmacological research<\/em>. 2013; 1: 15-26.<\/li>
  38. Prikhodko VA, Selizarova NO, Okovityi SV. Molecular mechanisms of hypoxia and adaptation to it. Part II]. Arkhiv Patologii<\/em>. 2021;83(3):62-69. [In Russian]. doi: 10.17116\/patol20218303162.
    CrossRef <\/a><\/li>
  39. Yilmaz S, Ozan S, Benzer F, Canatan H. Oxidative damage and antioxidant enzyme activities in experimental hypothyroidism. Cell Biochem Funct<\/em>. 2003;21(4):325-30. doi: 10.1002\/cbf.1031. PMID: 14624470.
     CrossRef <\/a><\/li>
  40. Haribabu A, Reddy V.S, Pallavi CH, Bitla AR, Sachan A, Pullaiah P et al. Evaluation of protein oxidation and its association with lipid peroxidation and thyrotropin levels in overt and subclinical hypothyroidism. Endocrine<\/em>. 2013; 44(1): 152\u2013157. doi:10.1007\/s12020-012-9849-y
     CrossRef <\/a><\/li>
  41. Sarand\u00f6l E, Ta\u015f S, Dirican M, Serdar Z. Oxidative stress and serum paraoxonase activity in experimental hypothyroidism: effect of vitamin E supplementation. Cell Biochem Funct<\/em>. 2005;23(1):1-8. doi: 10.1002\/cbf.1119. PMID: 15386442.
    CrossRef <\/a><\/li>
  42. Kebapcilar L, Akinci B, Bayraktar F, Comlekci A, Solak A, Demir T et al. Plasma thiobarbituric acid-reactive substance levels in subclinical hypothyroidism. Med Princ Pract<\/em>. 2007;16(6):432-6. doi: 10.1159\/000107747.
     CrossRef <\/a><\/li>
  43. Venditti P, Napolitano G, Barone D, Coppola I, Di Meo S. Effect of thyroid state on enzymatic and non-enzymatic processes in H2<\/sub>O2<\/sub> removal by liver mitochondria of male rats. Mol Cell Endocrinol<\/em>. 2015; 403:57-63. doi: 10.1016\/j.mce.2015.01.019.
     CrossRef <\/a><\/li>
  44. Cano-Europa E, Blas-Valdivia V, Franco-Colin M, Gallardo-Casas CA, Ortiz-Butr\u00f3n R.  Methimazole-induced hypothyroidism causes cellular damage in the spleen, heart, liver, lung and kidney. Acta Histochemica<\/em>. 2011; 113(1):1\u20135.
     CrossRef <\/a><\/li>
  45. Ortiz-Butron R, Blas-Valdivia V, Franco-Colin M, Pineda-Reynoso M, Cano-Europa E. An increase of oxidative stress markers and the alteration of the antioxidant enzymatic system are associated with spleen damage caused by methimazole-induced hypothyroidism. Drug Chem Toxicol<\/em>. 2011; 34(2):180-8. doi: 10.3109\/01480545.2010.4953
    CrossRef <\/a><\/li><\/ol>\n\n\n\n

    Abbreviations<\/strong><\/p>\n\n\n\n

    LID \u2013      – low iodine diet<\/p>\n\n\n\n

    TH \u2013       – thyroid hormones<\/p>\n\n\n\n

    CcOX     – cytochrome oxidase<\/p>\n\n\n\n

    MDH      – malate dehydrogenase<\/p>\n\n\n\n

    SDH       – succinate dehydrogenase<\/p>\n\n\n\n

    PC          – protein carbonyls<\/p>\n\n\n\n

    MDA       – malondialdehyde<\/p>\n\n\n\n

    PTU        – propylthiouracil<\/p>\n\n\n\n

    MMI        – methimazole<\/p>\n\n\n\n

    b.w.         \u2013 body weight<\/p>\n\n\n\n

    TPO        – thyroid peroxidase<\/p>\n\n\n\n

    ID            – iodine deiodinase<\/p>\n\n\n\n

    TBA        – thiobarbituric acid<\/p>\n\n\n\n

    ROS        – reactive oxygen species<\/p>\n\n\n\n

    fT3 <\/sub>          – free triiodothyronine<\/p>\n\n\n\n

    tT4                 <\/sub>– total thyroxine<\/p>\n\n\n\n

    CYP450 <\/sub>    – cytochrome P450<\/sub><\/p>\n","protected":false},"excerpt":{"rendered":"

    Introduction About 2 billion people in the world live in […]<\/p>\n","protected":false},"author":15,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[117],"tags":[],"class_list":["post-60767","post","type-post","status-publish","format-standard","hentry","category-vol17no3"],"_links":{"self":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts\/60767","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/users\/15"}],"replies":[{"embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/comments?post=60767"}],"version-history":[{"count":5,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts\/60767\/revisions"}],"predecessor-version":[{"id":61745,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/posts\/60767\/revisions\/61745"}],"wp:attachment":[{"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/media?parent=60767"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/categories?post=60767"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/biomedpharmajournal.org\/staging\/wp-json\/wp\/v2\/tags?post=60767"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}