Background: Complexes of iodine (povidone-iodine and cadexomers) are among the most important antiseptics used in clinical and veterinary medicines. However, high local irritation activity and systemic toxicity limits their oral administration. The purpose of the study was to compare the effect of a new complex of iodine (PA, potentiator of anticancer antibiotics), in which iodine is coordinated by carbohydrates and polypeptides) on the organisms of rats and dogs treated orally with the drug for 30 days. Methods: Wistar rats and Beagle dogs served as experimental animal models. Effect of PA on the animal organism was examined through the measurements of hormones level changes, hematological and clinical chemistry parameters alterations, necropsy and histological examination. Results: The established maximum tolerated dose (MTD) of 2,000 mg/kg PA led to a decrease in the rate of body weight gain in male and female rats. Changes in hematological and certain biochemical parameters in rats at doses of 1,000 and 2,000 mg/kg were observed. Histological study of the thyroid gland revealed changes in the shape and size of the follicles along with colloid resorption. Administration of a half of MTD (180 mg/kg) and lower doses did not result in any change in dogs (thyroid-stimulating hormone, triiodothyronine, and thyroxine). Conclusions: The results of our study show that the pathogenetic action of PA takes place along the path of induction of an inflammatory response with the development of thyrotoxicosis, rather than hypothyroidism. The mechanism of induction of an inflammatory response is also confirmed by histological studies of lesions of the thyroid gland and testes in rats (Figure S1). The no-observed-adverse-effect level (NOAEL) of PA is estimated to be 180 mg/kg (or iodine 22.8 mg/kg) in dogs, which is equivalent to 100 mg/kg (or iodine 12.3 mg/kg) in humans.

Interest in iodine complexes has increased significantly in recent years because of their wide spectrum of biological activity. The FS-1 is an ion nanostructured complex formed by proteins and/or polypeptides, carbohydrates, salts of alkali and alkaline earth metals with intercalated iodine. Patented in 2014, it is intended for the treatment of infectious diseases of bacterial origin including nosocomial infections and multidrug resistant tuberculosis. The aim of the study was to determine its acute and subchronic toxicity. The study of acute and subchronic toxicity was performed on adult Wistar rats according to OECD guidelines. The data on acute toxicity showed LD50 > 2,000 mg/kg after a single intragastric administration. Twenty-eight days of FS-1 administration at a dose of 500 mg/kg resulted in toxic effects. At a dose of 250 mg/kg, the toxic effects were temporary and a return to normal followed after the recovery period. Doses of 100 mg/kg had no adverse effects on the rats.

Urinary KIM-1 levels may be used to estimate the activity of CGN with NS and to evaluate the efficiency of treatment. The results of the study substantiate the search for ways of pharmacological blockade of KIM-1 production in the kidney in order to optimize the methods that impact on the pathogenesis of CGN progression.