Changes in the Glutathione System of Cat Blood under Diabetes Mellitus and Obesity

Abstract

The peculiarities of small carnivorous’ welfare, of cats in particular, caused the development of some metabolic pathologies, among which the most widely spread are diabetesmellitus and obesity. One of the most important releasers under these pathologies is the development of oxidative stress. The most powerful natural antioxidant system of an animal organism is glutathione system including glutathione and the enzymes which catalyze the reactions of its oxidation and renewal. Glutathione-tripeptide consists of two fractions-renewed and oxidized. The system also contains a few enzymes, the most important of which are glutathione peroxidase and glutathione reductase. The purpose of the research is to determine the concentration changes of the renewed and oxidized glutathione, the activity of glutathione peroxidase and glutathione reductase in cats suffering from diabetes and obesity. Four groups of cats-steer aged from 5 to 8-years old, 6–8 cats in each group were formed to conduct the research. A control group consisted of clinically healthy animals, the first experimental one consisted of the animals with excess weight and obesity, the second experimental group included the cats with diabetes (the diagnosis was ruled in by testing on fructosamine), the third experimental group included the cats with excess mass and diabetes. In most animals of the experimental groups were revealed some characteristics of concomitant pathologies – kidney and hepatic failures, in particular. The determination of glutathione concentration and of the enzymes of the glutathione system was made in red blood cells of venous blood, the concentration of glucose and fructosamine was determined in blood serum by means of spectrophotometric methods, also a qualitative analysis of urine on glucose, protein, urine ketones and blood was made. As follows from the results of the research, it has been determined that the animals of three experimental groups had similar changes in the state of glutathione system: the decrease in the part of renewed glutathione, the increase in the part of oxidized one. The decrease in the concentration of the renewed glutathione was the least in cats of the first experimental group and equaled to 7% as compared to the control, in the animals of the second group it equaled to 15%, and in the animals of the third group it was the biggest – 18%. The activity of glutathione peroxidase increased in the animal blood of experimental groups as compared to the control; as for the activity of glutathione reductase the animals of the of the second experimental group had an insignificant increase in the enzyme activity-up to 8% as compared to healthy animals, and in the animals of the of the second and third experimental groups the activity of this enzyme decreased by 13% and 40.3% correspondingly. Thus, it has been determined that in cats with obesity and diabetes mellitus the part of renewed glutathione decreased and its oxidized part increased, herewith the activity of glutathione peroxidase increased both under obesity and under diabetes, the activity of glutathione reductase increased insignificantly in cats with excess mass, and in cats with diabetes and in combination with two pathologies the enzyme activity decreased. The lowest level of changes had the cats with excess mass and obesity, the highest one had the animals with excess mass and diabetes.