In scientific work for the first time the mineral homeostasis, energy synthesis system, prooxidant-antioxidant balance and structural organization of dental cementum, hard and soft tissues of periodontium in intact and insulin-resistant rats under conditions of proper iodine supply and iodine deficiency was examined. In animals the iodine deficiency (1st group, n=30), insulin resistance in case of proper iodine supply (2nd group, n=30) and on the background of iodine deficiency
(3rd group, n=30) was modelled. The control group (n=30) included intact animals, which were kept in conditions of standard diet and water regime of vivarium. It was found that development of combined endocrine pathology is accompanied by a decrease of calcium and magnesium content in dental cementum, bone tissue of alveolar processes by 26.7-52.3 % with a simultaneous increase of macroelements concentration in erythrocyte mass in 6.7-22.3 times compared with data in animals with isolated iodine deficiency or insulin resistance. Herewith, the level of manganese in erythrocyte mass of rats with combined endocrinopathy is lower by 83.3 % relative to the values in animals of 2nd research group. It was proved, that insulin resistance on the background of iodine deficiency causes an increase of acid phosphatase activity in blood serum by 44.3 % in comparison to the corresponding indicators of rats with impaired glucose tolerance. The codirected increase of alkaline and acid phosphatases activity by 90.2 % and in 2.4 times, respectively, in animals of 3rd research group relative to the values in rats with isolated iodine deficiency can characterize a compensatory regenerative ability of bone tissue under such conditions. It is found for the first time, that hypoxic tissue changes in rats with insulin resistance on the background of iodine deprivation is characterized by a decrease of succinate- and lactate dehydrogenase activity in blood serum by 87.7 % and 63.8 %, respectively, in comparison to analogical indexes of rats with isolated iodine deficiency, and also succinate- and malate dehydrogenase – by 67.8 % and 46.0 %, respectively, to the activity of blood serum dehydrogenases in animals of
2nd research group. It was noted, that development of combined endocrine pathology leads to elevation the content of most oxidative proteins modifications fractions in 4.3-8.4 times with a simultaneous slowdown of this process in blood serum in comparison to analogical indexes of intact rats. It was detected that development of combined endocrinopathy is accompanied by acumulation of dienic conjugates and products, that react to thiobarbituric acid content in 4.6-19.0 times in all studied tissues compared with similar indicators of intact rats and also by 28.8 % – in 3.9 times in oral mucosa of alveolar processes relative to analogical indexes in animals with iodine monodeficiency or isolated insulin resistance. Under such conditions, there is an increase of glutathione peroxidase and glutathione reductase activity in 4.9 and 6.3 times, respectively, against the background of suppression of superoxide dismutase activity by 26.4 % and a decrease the level of transferrin saturation by iron by 53.3 % relative to similar indicators in animals with monoiodine deficiency and suppression of superoxide dismutase activity by 21.4 % and decreased ceruloplasmin content by 47.0 % in comparison to antiradical status of insulin-resistant animals. The glycation of bone base of periodontium under conditions of insulin resistance on the background of hypothyroid dysfunction leads to osteopenic and osteoresorptive changes of alveolar processes with the simultaneous accumulation of unsulfated glycosaminoglycans in the bone matrix, which is manifested by a decrease of its optical density compared to baseline. Structural rearrangement of oral mucosa of alveolar processes unser such experimental conditions is characterized by connective tissue edema, macrophage-leukocyte infiltration, hyperplastic changes of the epithelium, accumulation of unsulfated glycosaminoglycans and acanthotic changes. Microcirculatory system is characterized by the narrowing of capillaries and arterioles lumen, slightly pronounced endothelial hypercellularity, accumulation of glycoproteins in the venules wall, which gradually leads to the loosening of vascular wall and significantly change the nutrition of periodontium tissues. Thus, the development of insulin resistance under iodine deficiency conditions is accompanied by the changes of demineralization processes of periodontium tissues, suppression of energy synthesis processes, activation of prooxidative reactions in periodontium soft tissues against the background of antiradical defense system depletion, that is accompanied by structural restructuring of all periodontium elements. Key words: periodontium tissues, mineral metabolism, structural and metabolic features, insulin resistance, iodine deficiency. Branch – medicine.
