ANTIOXIDANT EFFECT OF EXTRACT OF YELLOW FRUITS OF CORNELIAN CHERRY (CORNUS MAS L.) IN RATS’ LEUKOCYTES UNDER STREPTOZOTOCIN-INDUCED DIABETES MELLITUS

Abstract

Background. The chronic hyperglycemia and intensified metabolic pathways of glucose conversion lead to the formation of excessive amounts of the reactive oxygen species and the development of oxidative stress under the condition of diabetes mellitus. In the recent decades, scientists have been searching for new drugs based on plant materials to prevent metabolic, structural and functional disorders in the body under diabetes. It has long been known that fruits and vegetables are sources of biologically active substances that have a beneficial effect on human health. The yellow fruits of the cornelian cherry (Cornus mas L.) contain a significant amount of substances (iridoids, phenolic acids and flavonoids), whose properties, biological effects and mechanism of action are not fully understood.
The aim of the study was to investigate the effect of the extract of yellow fruits of the cornelian cherry on the reactive oxygen species content and the activity of antioxidant enzymes in rats’ leukocytes with streptozotocin-induced diabetes mellitus.
Materials and Methods. Experimental diabetes mellitus in rats was induced by intraperitoneal administration of streptozotocin. The development of diabetes mellitus was monitored by blood glucose level. From the 10^th day after the induction of diabetes, the animals were orally administered the extract of yellow fruits of the cornelian cherry at a dose of 20 mg/kg of the body weight for 14 days. On the last day of the experiment, we collected the blood into vials with heparin and isolated leukocytes to further determine the content of reactive oxygen species and the activity of antioxidant enzymes. Statistical analysis of the results was performed using MS Excel-2013.
Results. The content of the reactive oxygen species is increased and the activity of antioxidant enzymes is reduced in the rats’ leukocytes during streptozotocin-induced diabetes mellitus. Oral administration of the extract of yellow fruits of the cornelian cherry to diabetic animals improves the antioxidant status of leukocytes, which is manifested in an increased activity of superoxide dismutase, catalase and glutathione peroxidase along with a decrease in the level of intracellular reactive oxygen species.
Conclusions. The extract of yellow fruits of the cornelian cherry (Cornus mas L.) restores the balance between prooxidants and antioxidant defense system in leukocytes of rats with streptozotocin-induced diabetes mellitus. Such results suggest that the extract of yellow fruits of the cornelian cherry might be one of the plant components in the development of new drugs that will correct metabolic and functional disorders in leukocytes under diabetes.