State of endothelial function, lipid spectrum and features of coronary vessels structure of rats with obesity and insulin resistance under iodine deficiency conditions

The aim of the study was to investigate the changes of endothelin-1 content, blood lipid spectrum parameters, structural features of coronary vessels of rats with insulin resistance and obesity under conditions of adequate iodine supply and iodine deficiency. For the modeling of insulin resistance, rats were kept on high-fructose, obesity – high-calorie, iodine deficiency – iodine deficiency diets. It was found that the development of insulin resistance, obesity and iodine deficiency was accompanied by an increase of endothelin-1 level in 2.41, 2.31 times and at 80.17% in blood serum, relative to the data in intact animals. Insulin resistance and obesity under conditions of limited iodine supply leads to the significant changes in endothelial dysfunction (increase in the level of endothelin-1 in 3.02 and 2.50 times relative to control and at 67.38 and 39.40% – relative to mono iodine deficiency) and dyslipidemia (increase in the atherogenic factor at 48.08% – 4.20 times relative to isolated insulin resistance, obesity and iodine deficiency). Such changes were consistent with the structural violations. In insulin-resistant animals focal unevenness of the outer and inner contours, their uneven thickness, areas of homogeneous enlightenment were observed under the conditions of iodine deficiency in the arterioles and minor arteries of the myocardium. In obese animals under the conditions of iodine deficiency, the vessels of the microcirculatory bed were dilated and overflown with erythrocytes. Endotheliocytes with nuclei elongated along the wall, in some places there is a swelling of the cytoplasm of endotheliocytes. In the wall of minor arteries there are transparent vacuoles, areas of homogeneous eosinophilia, which are caused by the accumulation of glycoproteins. Thus, the development of insulin resistance and obesity in iodine deficiency is accompanied by more significant changes in endothelial function and an increase in proatherogenic fractions in the blood lipid spectrum, as evidenced by changes in the structural organization of myocardial vessels than with proper iodine supply.

The Nutritional Supply of Iodine and Selenium Affects Thyroid Hormone Axis Related Endpoints in Mice

Selenium and iodine are the two central trace elements for the homeostasis of thyroid hormones but additional trace elements such as iron, zinc, and copper are also involved. To compare the primary effects of inadequate intake of selenium and iodine on the thyroid gland, as well as the target organs of thyroid hormones such as liver and kidney, mice were subjected to an eight-week dietary intervention with low versus adequate selenium and iodine supply. Analysis of trace element levels in serum, liver, and kidney demonstrated a successful intervention. Markers of the selenium status were unaffected by the iodine supply. The thyroid gland was able to maintain serum thyroxine levels even under selenium-deficient conditions, despite reduced selenoprotein expression in liver and kidney, including deiodinase type 1. Thyroid hormone target genes responded to the altered selenium and iodine supply, whereas the iron, zinc, and copper homeostasis remained unaffected. There was a notable interaction between thyroid hormones and copper, which requires further clarification. Overall, the effects of an altered selenium and iodine supply were pronounced in thyroid hormone target tissues, but not in the thyroid gland.

State of iodine supply of children with chronic somatic diseases

One of the most common conditions resulting from micronutrient deficiency is iodine deficiency. Purpose — to evaluate the current state of iodine supply in schoolchildren living in the North-Eastern region of Ukraine, including children with digestive diseases and inflammatory joint diseases. Materials and methods. Target group: 86 people (11.8±2.71 years), which included patients with digestive diseases (DD) (26.7%) and juvenile idiopathic arthritis (JIA) (60.5%). Methods: dietary iodine intake evaluation by urinary iodine concentration (Sandell–Kolthoff reaction), followed by calculation of the median. Results. Median urinary iodine excretion was at the lower normal range and amounted to 104.98 μg/l [QR: 59.8; 180.1] in the examined children. Only 51.2% of children had adequate iodine provision; mild iodine deficiency (ID) was diagnosed in 29.1% (Ме=81,91μg/l [QR: 64.26; 90.58]); moderate — 17.4% (Ме=36,19 μg/l [QR: 33.54; 42.24]); severe — in 2.3% of the surveyed (Ме 14,02 μg/l [QR: 12.34; 15.70]). The median urinary iodine excretion in children with somatic diseases was significantly lower than in children of the control group and amounted to 97.26 μg/l [QR 53.7; 148.3] versus 183.71 μg/l [QR 104.4; 287.4], (p=0.003). Conclusions. School-age children have a high incidence of iodine deficiency (51.2%). Often encountered in childhood diseases (DD and JIA) are accompanied by insufficiency of iodine supply. The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local Ethics Committee of all participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the author. Key words: iodine deficiency, school-age children, the level of iodine excretion.

Socio-ecological and medical problems of iodine deficiency among the population of Ukraine

Aim. Study of iodine supply in different segments of the population throughout Ukraine, establishment of the morbidity level caused by iodine deficiency, analysis of preventive measures and their effectiveness and development of adequate ways of mass, group and individual prophylaxis of iodine deficiency in the body, which will reduce morbidity in areas of endemic iodine deficiency. The article considers the most important results of long-term epidemiological studies of iodine supply in different categories of the population of almost all regions of Ukraine. Significant volume of work was performed with the support of the Ministry of Healthcare of Ukraine, UNICEF Ukrainian office, and the CDC in Atlanta (USA), which for more than 19 years has provided external quality control of the study of iodine status of the population of Ukraine. The data on iodine content in food and biological fluids of the population affected by the Chernobyl accident are given and the dependence of the irradiation dose of the thyroid on the body supply with stable iodine and on the optimization of the latter after the adoption of the State Programme for Iodine Deficiency Prevention for 2002–2005 is shown. The effectiveness of mass iodine prophylaxis by using universally iodized table salt is emphasized. The article presents data on suggested and implemented ways of mass, group and individual iodine prophylaxis, studies of their effectiveness and shows the positive dynamics of changes in providing the population with dietary iodine. The need for constant consumption of food products with sufficient iodine content, including iodized salt, is proven. Significant changes in the prevalence and incidence of thyroid pathology, socio-ecological and medical benefits of prevention of iodine-dependent disorders are described. The article was prepared as a scientific information material for family doctors, endocrinologists, obstetricians and gynaecologists, hygienists, the public, the Ministry of Healthcare of Ukraine in connection with the need for a legislative solution to the prevention of iodine-dependent disorders in Ukraine. Materials and Methods. To study the problem and assess the state of iodine deficiency in Ukraine the criteria recommended by the WHO and the United Nations Children’s Fund (UNICEF) were applied for the first time, a method for determining the iodine content in the body was developed and implemented, which allowed to join the international “Equip” system of iodine supply control in the world and in Ukraine. This made it possible to move from indirect to direct methods of determining the intake of iodine in the body. Conclusions. A detailed study of iodine supply in different segments of the population of Ukraine proved the negative effects of iodine deficiency on health; in particular, it was found that the overall decrease in productivity of the generation of children in iodine deficiency populations is 5%. Measures to eliminate iodine-dependent disorder among the population of Ukraine have been developed and implemented. The development and production of iodized food salt, adequate to the needs of the population, has been carried out. The result of these measures, developed and implemented to eliminate iodine-dependent disorders and to improve the nation’s intelligence, is, according to the official data, the improvement of iodine supply of the population, significant reduction in the number of thyroid disorders, especially among those affected with 131I, which, even just because of this indicator, has significant social-economic effect. Key Words: Chernobyl accident, iodine deficiency, iodized salt, population, prevention, regions.

The state of iodine supply of prepubertal children living in the Northern Bukovina

Background. In Bukovina, depending on climatic and geographical zones, there is a mild and moderate degree of iodine deficiency. Assessment of urinary inorganic iodine excretion allows monitoring of the epidemiological situation regarding the severity of iodine deficiency in the region. The purpose was to assess the indicators of ioduria in prepubertal children living in the Northern Bukovina (Chernivtsi region). Materials and methods. As part of a 20-cluster analysis of the prevalence of goiter among the pediatric population of Chernivtsi region, 1,973 children aged 7 to 12 years were examined and the concentration of inorganic iodine in a single portion of urine was determined in 197 children. The obtained results were processed by the method of statistical variation and correlation analysis. Results. Manual palpation examination showed a significant incidence of goiter among children in Bukovina — 17.6 %. Thyromegaly among children of the reference group occurred in 15.1 % of cases. The median ioduria in the examined population is generally 60.4 μg/l. The average prevalence of iodine deficiency was 59.70 ± 1.82 %, the incidence of severe iodine deficiency did not exceed 5.22 ± 1.30 %. Analyzing the degree of iodine supply of children depending on the geographical areas of residence, we conclude that children li­ving in the plains and children from Chernivtsi have mild iodine deficiency (median ioduria is 72.2 and 70.4 μg/l, respectively), and children from mountainous areas — moderate iodine deficiency (median ioduria is 42.9 μg/l). The average prevalence of iodine deficiency was 59.70 ± 1.82 %, and excessive iodine in the urine — 18.70 ± 2.49 %. Moreover, the incidence of severe iodine deficiency did not exceed 5.22 ± 1.30 %. Conclusions. In most children living in Northern Bukovina, the median ioduria is reduced. In 18.7 % of children, the iodine content is more than 300 μg/l, which requires further monitoring.

A „silent” jódprofilaxis csak részben korrigálja a jódhiányt: a magyar történet (1970–2020)

Összefoglaló. A szerző a bevezetőben emlékeztet a több mint 50 évvel korábbi publikációjára (Orv Hetil. 1968; 109: 360–363) és annak utóéletére: az 1970-es években megállt a jódprevenció fejlődése. Ezt követően ismerteti az utóbbi 50 év jódellátottságra vonatkozó fontosabb hazai eredményeit. A számszerű adatok szerint az iskolás gyermekek, várandós anyák, idősek és újszülöttek jódellátottságára, valamint az anyatej jódtartalmára vonatkozó sorozatvizsgálatok az ezredforduló előtt egybehangzóan enyhe, illetve mérsékelt jódhiányra utaltak. Az utóbbi két évtizedben egyre többször váltak adekváttá az ugyanezen kategóriák jódellátottságát jelző eredmények. A szabályozatlan jódozottsó-forgalom (fakultatív jódprevenció) ellenére, valószínűleg a sikeres felvilágosítási kampányok miatt, a lakosság jódellátottsága határozottan javult. Ezt a szituációt nevezik „silent” profilaxisnak. Ezzel a módszerrel nem lehet a jódhiányt teljesen felszámolni. A legnagyobb kockázatot a várandós anyák (közel felének!) hiányos jódpótlása jelenti az utódok agyfejlődésének veszélyeztetése miatt. A befejezésben az EUthyroid Consortium „Krakkói kiáltvány”-ának (2018) rövid ismertetése tartalmazza a teendőket. A kötelező jódprevencióhoz a nem jódozott sót ki kell váltani jódozott sóval szinte minden élelmiszerben. A graviditás alatt megnövekedett igényt az élelmiszerekben lévő jód gyakran nem fedezi, ilyenkor több jódpótlásra van szükség. Az egészségügyi szerveknek meg kell valósítaniuk a jóddúsító program összehangolt, rendszeres monitorozását és kiértékelését a lakosság optimális jódellátottságának biztosításához. Orv Hetil. 2020; 161(50): 2107–2116. Summary. In the introduction, the author reminds the readers of his publication presented more than 50 years ago in the same journal („Data to the present state of the goiter problem in Hungary”, 1968) and of its afterlife: the development of iodine prevention stopped in the 1970s. Then the major Hungarian results are reviewed related to the iodine supply gained in the latter 50 years. Numerical data are presented showing mild or moderate iodine deficiency according to the results of a range of screening studies among schoolchildren, pregnant women, elderly people and newborns as well as by iodine content of breast milk before the millennium. In the same categories, the data indicating the level of iodine supply became increasingly adequate in the recent two decades. The iodine supply of the people improved markedly, in spite of unregulated iodized salt trade (facultative prevention), presumably because of the successful public-information campaigns. This situation is called “silent” prophylaxis. The total eradication of iodine deficiency is impossible with this method. The highest risk is the deficient iodine supply of pregnant women (almost the half!) due to the endangerment of the offspring’s brain development. In the end, a brief review of the Krakow Declaration on Iodine of the EUthyroid Consortium comprises the round of the duties. To the mandatory iodine prevention, iodized salt should replace non-iodized salt in nearly all food productions. During pregnancy, the increased need for iodine is frequently not covered by food sources, more iodine supplement is needed. Health authorities should perform harmonized monitoring and evaluation of fortification programs at regular intervals to ensure optimal iodine supply to the population. Orv Hetil. 2020; 161(50): 2107–2116.