INDICATORS OF OXIDATIVE STRESS IN RATS POISONED BY HIGH DOSES OF SODIUM BENZOATE

Abstract

Introduction. The scientific literature contains the results of studies on the effect of the food preservative sodium benzoate on the structure and functioning of biological objects, but they are quite contradictory. According to official data from the World Health Organization (WHO), the use of sodium benzoate in the food industry is limited to 0.1%, and the permissible daily intake of this preservative is 5 mg/kg per day. However, it is used in much higher concentrations in many food products, medicines, and cosmetics. The powerful pro-oxidant effect of sodium benzoate has been proven on aerobic yeast populations.The aim of the study – to investigate the effect of increased doses of sodium benzoate on the activity of oxidative processes and indicators of the antioxidant system of the rat body.Research methods. The study was conducted on white male rats with a body weight of 170–180 g, which were kept on a standard diet of the vivarium of the I. Ya. Gorbachevsky National Medical University. The experimental rats were divided into 3 groups. The first group consisted of intact rats, the rats of the second group received sodium benzoate at a dose of 10 mg/kg of body weight. The third group of rats was administered sodium benzoate at a dose of 30 mg/kg of body weight. The rats received the preservative intragastrically daily in the above doses.The study was conducted in accordance with the requirements of good laboratory practice (GLP) and bioethics in accordance with the European Convention for the Protection of Vertebrate Animals. The animals were euthanized under thiopental anesthesia. Rats were removed from the experiment 7, 14, 21 and 28 days after the start of sodium benzoate administration. The content of TBA-active products, oxine modification of proteins, reduced glutathione and catalase activity were studied in blood serum and liver homogenate.Results and Discussion. It was found that within 28 days the content of TBK-AP progressively increases in the blood serum and liver of animals. By the end of the experiment, the content of TBK-AP in the blood serum of rats (dose of toxicant 30 mg/kg body weight) exceeded the level of intact rats by 5 times. After poisoning rats with sodium benzoate at a dose of 10 mg/kg body weight of rats in the first week of the study, an increase in this indicator in the liver was not probable. By the end of the experiment, it increased by 216%. During the same period, when using a dose of toxicant 30 mg/kg, the content of TBK-AP exceeded the norm by 268%. It was found that the content of OMP products of both fractions significantly (p≤0.05) increased in the blood serum and liver of poisoned rats at all times of the study when using both doses of sodium benzoate. In animals poisoned with sodium benzoate, the content of reduced glutathione decreased at all times of the study both in the blood serum and in the liver of rats compared to the norm. A decrease in catalase activity was noted both in the blood serum and in the liver of affected animals throughout the experiment. The dose of sodium benzoate 30 mg/kg was more toxic, after its administration to the rat body, a significant decrease in catalase activity was noted in the blood serum from the 14th day of the study, and in the liver throughout the experiment.Conclusions. It has been experimentally proven that administration of sodium benzoate to animals in increased doses (10 and 30 mg/kg of body weight of animals) activates the processes of lipoperoxidation and oxidative modification of proteins, which leads to the development of oxidative stress. A decrease in the activity of the body's antioxidant defense system was registered, which was accompanied by a significant (p ≤ 0.05) decrease in catalase activity and the content of reduced glutathione at all times of the experiment. A dose of sodium benzoate of 30 mg/kg of body weight caused more pronounced changes in the studied biochemical parameters throughout the study (28 days).