Comparative Research of Osteoassociated Micronutrient Levels of Copper in Bone Tissue under the Influence of Lead in Macro and Nanoquenchhelate Form on Animals in Experimental Conditions

Nowadays population's morbidity connected with bone and muscular system diseases increases rapidly. In addition, there is a tendency of skeleton's strength reducing and technogenic pressure on the human body increasing. All these factors determine the need for hygienic analysis of the osteoassociated trace elements role, including copper, in the development of osteopathy in the industrial city population. Bone tissue has the highest cumulative properties in the human body, in relation to many xenobiotics, in particular to the group of heavy metals, among which lead is leading in the degree of bone tissue affinity. Essential micronutrients, including copper, play an important role in bone remodeling. Thus, copper is an activator of bone mineralization and is involved in the synthesis of organic substances for bone formation. In this regard, the purpose of the study is to investigate the effect of the isolated action of lead compounds in the macro- and nanoacquale form on the content of copper in the bone tissue of laboratory animals under experimental conditions. Materials and methods. Wistar rats were selected for experimental research. The experiment was conducted by means of methodological approaches that meet the current international requirements for toxicological experiments using animals in accordance with the European Convention. Animals were randomly assigned to two subjects and one control group with homogeneity in average weight. The dose of lead acetate (macrophage of lead) is close to 1/30000 LD50, corresponds to 0.05 mg/kg body weight, administered in isolation (the second experimental group) and lead citrate (nanoacqualate form of lead) - at a dose of 0.05 mg/kg (the third experimental group). Rats of the control group (the first group) got distilled water at the same time. For the maximum approximation of the experiment to the natural conditions, the oral route of administration according to the methodological recommendations for the study of the toxicity of metals - by the intragastric probe was chosen. The strand bone was prepared and isolated according to generally accepted techniques. Research results and its discussion. It was found out that the copper content in the bone tissue was lower than in the control group of animals, under the conditions of low-dose exposure to lead. Thus, the copper concentration decreased by 43.5% (p<0.01) and was 3.87 ± 0.28 mg/kg compared with the control group, the similar figures of which correspond to 6.85 ± 0.7 mg/kg. The resulting effect contributes to a violation of the ratio Zn: Cu, due to copper deficiency, which, in turn, affects the concentration of zinc, proven lead bioanagonist. Consequently, the cascade of violations of the bones' mineral composition can cause certain morphological changes and development of osteopathies. Among the animals of the third group, the content of the investigated microelement decreased by 44.8% (p <0.01) and was 3.78 ± 0.15 mg/kg compared to the bone tissue of the control group rats. The comparative research of experimental groups indicated that there was no significant difference between the effect of the macro- and nanoacqualate form of lead on the copper content in the bone tissue, that is, lead acetate and lead citrate almost equally contribute to a decrease in the bone content of copper in the average by 44.2%. Results. During isolated low-dose exposure of lead acetate (lead macrophage) and lead citrate (nanoacquale form) copper content in bone tissue decreases to 43.5% (p<0.01) and 44.8% (p<0.01) respectively. The results of the copper reduction, breaking the ratio Zn: Cu, due to a significant deficit of the latter, affects the concentration of zinc, which is proven lead bioanagonist.