Determination of the Effect of Thymoquinone on DNA Damage in Kidney Cells Treated to High Glucose Depending on Time and Dosage by Comet Assay

Abstract

The purpose of this study was to assess the anti-genotoxic potential of thymoquinone (TQ) against DNA damage in NRK-52E cells treated with high glucose using the comet assay technique single cell gel electrophoresis method. Cells were propagated by regular passages in in vitro conditions. TQ proliferative concentration (10μM) and IC25 (3rd-hour: 550 mM, 12th-hour: 240 mM, 24th- hour: 200 mM) and IC50 (3rd-hour: 760 mM, 12th-hour: 400 mM, 24th-hour: 280 mM) values for each hour of high glucose and were determined separately with MTT method. At these concentrations, the cells were divided into control(C), Thymoquinone (TQ), high glucose(G) and high glucose plus thymoquinone (GT) groups; It was incubated with the indicated substances for 3, 12, 24 hours. DNA damage was evaluated by applying the comet assay protocol and the results were calculated as DNA damage index (DDI). While DDI levels were observed to be significantly higher (p<0.05) in all groups administered high glucose compared to the control, a significant decrease was determined in all groups in which TQ was added along with high glucose. It was determined that high concentrations of glucose had genotoxic effects on kidney cells, and TQ administration together with high glucose, depending on concentration and time, had a significant effect on reducing DNA damage. However, it was concluded that the application of only thymoquinone significantly increased the DDI value compared to the control, and this was a data worth investigating in future studies. Additionally, TQ inhibited DNA damage. These results demonstrated the importance of TQ against nephrotic syndrome with its high antioxidant properties.