The investigation of protective effect of quercetin on oxidative stress induced in rats of 2,3,7,8-TCDD (tetrachlodibenzo-p-dioxin)

Advancing technology and new production techniques have brought biochemical pollution with them. Although the effects of many toxic substances have been found on the environment and living organisms, dioxin and dioxin-like substances are among the most commonly encountered and have the highest toxicity. The aim of this study was to investigate the effects of sub-chronic TCDD applications at different dosages on oxidant-antioxidant systems in rats, and the protective role of quercetin in this respect.A total of 28 male Wistar Albino rats weighing between 250-350 g were used in the present study. Rats were divided into four groups each of which including seven rats. The experiment period was planned as 8 weeks. During the study period, Group 1 was the control group and 0.5 mL of corn oil was applied with gavage. Group 2 was applied 2 mg / kg 2,3,7,8-TCDD (tetrachlo-p-dioxin), Group 3 was applied 20 mg/kg of quercetin and Group 4 was applied quercetin + TCDD. At the end of the eighth week, the rats were sacrificed and their heart and vascular tissues were taken for biochemical analysis.It was observed that hearth tissue SOD, CAT and GSH-Px activities and GSH levels have significantly reduced in Group 2 compared to control group. Although the increase in these enzyme activities is statistically significant in Group 3, no significant change has been observed in their GSH levels. It was observed that the increase in SOD, CAT and GSH-Px levels in Group 4 is statistically significant than Group 2.It was observed that the decrease in vascular tissues SOD, CAT and GSH-Px activities and GSH levels in Group 2 was statistically significant; the increase in SOD and GSH-Px activities in Group 3 was statistically significant. But in terms of CAT activities and GSH levels no statistically significant change was observed between these two groups. While the increase in GSH-Px activities in Group 4 was statistically significant than Group 2, no significant change has been observed between these groups.It was determined that the increase in MDA levels in hearth and vascular tissues in Group 2 was statistically significant than control group. But no statistically significant change was observed in Group 3 than control group. It was determined that the decrease in MDA levels in Group 4 was statistically significant than Group 2.In conclusion, the results of the study in cardiovascular system showed that quercetin decreased TCDD-induced lipid peroxidation, and supported antioxidant activity. Therefore, it can be suggested that quercetin has the potential for the treatment against the toxicity caused by TCDD and/or other environmental contaminants.