Etiology and pathogenesis of the oxidative stress in dogs and pharmacology correction with natural antioxidants

Oxidative stress is the process of cell damage as a result of oxidation. It reflects an imbalance between the manifestations of reactive oxygen species (ROS) in the organism and the ability of the biological system to cleanse itself of intermediate products of peroxidation and restore the damage caused timely. Free radical oxidation is normally one of the necessary factors of homeostasis, since reactive oxygen species with an unpaired electron perform useful functions, they are necessary mediators of many processes of normal cell functioning, such as the biosynthesis of prostaglandins, leukotrienes and other biologically active substances, and also accept participation in pathological processes, such as inflammation, fever, etc. BPO is a process of direct transfer of oxygen to the substrate with the formation of peroxides, ketones, aldehydes, etc. The article presents data on the study of the state of the dog’s antioxidant system under established oxidative stress of various etiologies, as well as the correction of these processes with the use of pharmacological (E-selenium, alpha-lipoic (thioctic) acid) and natural (quercetin in the composition of green buckwheat) antioxidants. The experiment used 20 dogs, aged 1-2 years, weighing 10-15 kg, which were divided into four groups: I group – control, II, III and IV – experimental. Dogs in group I did not remove antioxidants, in group II received the drug "E-selenium" subcutaneously at the dose of 0.04 cm 3 for one time only and "Quercetin" orally at the dose of 100 mg/kg daily, group III received alpha-lipoic acid in the amount of 10 mg per animal daily, and group IV was fed powder of unprocessed steamed buckwheat grain (as a source of quercetin) personally at the rate of 2 g per 10 kg of body weight. Blood was examined for the intensity of lipid peroxidation (LP) and enzymes activity on the 14th day of the experiment. It was established that a single subcutaneous injection of "E-selenium" in a dose of 0.04 cm 3 and "Quercetin" orally at the dose of 100 mg/kg daily, alpha-lipoic acid in the amount of 10 mg per animal and adding to the feed a powder of raw steamed buckwheat grains (as a source of quercetin) individually at the rate of 2 g per 10 kg of body weight stimulated the processes of antioxidant protection in the body of experimental dogs. This was characterized by inhibition of the processes of lipid peroxidation (LP) (decrease in the concentration of primary and secondary TBARS-active products – diene conjugates (DC) and malondialdehyde (MDA), and there was also an increase in the activity of antioxidant enzymes (catalase and superoxide dismutase (SOD) and restoration of the pool of endogenous total antioxidant activity (TOA).