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

Abstract

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.