THE EFFECT OF COMPOSITE MEDICINE OF PLANT ORIGIN IN EXPERIMENTAL HYPOTHYROIDISM

Abstract

One of the aspects of the complex pathogenesis of AIT and the accompanying complication of hypothyroidism is related to the reduced metabolic activity of minerals and vitamins that protect the thyroid gland from oxidative stress. It is known that the full functioning of the immune system requires a balance of vitamins, microelements, minerals, amino acids and fatty acids. Their deficiency or imbalance causes the progression of many diseases associated with disorders of the immune system. The question of the effective use of plant-based agents in combination with vitamins in the complex treatment of AIT to restore thyroid function receives little attention, their justified use is extremely relevant today. The aim: to study in an experiment the effectiveness of a composite agent of plant origin, which includes tannin, potassium iodide and vitamin C, for the correction of hypothyroidism of autoimmune genesis and accompanying metabolic disorders.

Materials and methods. The study was conducted on 60 sexually mature male non-linear rats. Autoimmune hypothyroidism (AIH) in rats was induced by immunizing animals with thyroid antigen in combination with complete Freund's adjuvant. A composite agent of plant origin (biologically active supplement, which includes tannin, potassium iodide, vitamin C) called Samirin (SM) was administered for 10 days in a 10% starch solution at the rate of 300 mg of the active substance per 1 kg of body weight, the comparison drug "L-thyroxine" (LT₄) was administered in a 2% starch solution at a dose of 10 μg/kg body weight within 10 days. The intensity of lipid peroxidation (LPO) was assessed by the accumulation of diene conjugates (DC) and malondialdehyde (MDA) in blood plasma. The activity of catalase and superoxide dismutase (SOD) of erythrocytes was determined as the main indicators of antioxidant protection (AOP). Statistical analyses were carried out using parametric methods. The normality of the distribution was determined using the Kolmogorov-Smirnov test. To compare indicators characterized by a normal distribution, the unpaired Student's t-test was used. Data shown as mean ± standard error of the mean. The difference was considered reliable at P<0.05.

Results. It is shown that in animals with AIH, on the background of a reduced level of thyroid hormones, processes of activation of lipoperoxidation and inhibition of the enzyme part of the antioxidant defense system occur. At the same time, these processes tended to deepen over time: after 3 months, studies in animals with AIH persisted signs of imbalance of the LPO-AOP system. After 1-month observations, in the groups of rats with AIH administered SM and LT₄, the MDA and DC levels were probably lower than in rats in the AIH group, they practically did not differ from the control values. After 3 months, rats in these groups had a significant normalizing effect specifically on peroxidation processes. At the same time, both substances contributed to maintaining the SOD activity at a sufficiently high level relative to AIH group without therapy, and the effect of SM was more pronounced.

Conclusions. The use of the compositional plant-derived product Samirin or L-thyroxine neutralized the increase in lipoperoxidation caused by experimental hypothyroidism of autoimmune genesis. In the long term, the protective effect of Samirin on the enzyme component of the antioxidant defense system was observed. The identified properties will allow Samirin to be used in medical practice in the future not only for complex treatment of hypothyroidism and its metabolic complications, but also for other diseases accompanied by oxidative stress.