Evaluating the effect of thymoquinone on the tert-butylhydroquinone geno/ cytotoxicity in the HUVEC cell line

Abstract

Background and objective: Additives are added to a numerous of processed foods to maintain their quality, taste and appearance of food during the processing, packaging and storage. However, food additives are known as synthetic products which has risks to public health. 2-tert-Butyl-4-hydroquinone (TBHQ) is used in the food industry as a phenolic antioxidant to prevent oxidative oils. This antioxidant can also affect cytotoxicity and genotoxicity in Human umbilical endothelial cells (HUVECs). Recent studies have been attempting to reduce the toxicity of synthetic antioxidants through natural antioxidants, among these compounds, thymoquinone is a bioactive ingredient of black seed which have been able to reduce the effects of various toxins. Therefore, the aim of this study was to determine the effect of thymoquinone on cytotoxicity and genotoxicity of TBHQ on HUVEC cell line. Methods: The cytotoxicity effect of antioxidants such as thymoquinone, TBHQ, TBHQ plus thymoquinone, in HUVEC cell line was assessed using MTT assay and flowcytometry beside the genotoxicity effect of the aforementioned antioxidants was evaluated using, DNA damage and chromatin fragmentation methods. Also, DPPH method was used to compare the synergistic effect of antioxidant activity. Results: The results of MTT assay for determination of cell vabiafter 24 and 48 hours showed that 5, 10 and 15 μm of thymocinone had protective effect on TBHQ-treated cells (60 μM), as well as the highest protective effect of thymquinone on TBHQ was at 10 μm concentration (p<0.001). Also, in combined regime of TQ and TBHQ, apoptosis was significantly reduced compared to the cell treated with TBHQ (p<0.05). Similarly, TQ had a protective effect on DNA and chromatin fragmentation of cells treated with TBHQ. The results of DPPH showed that thymoquinone had no effect on the antioxidant activity of TBHQ. Conclusion: Finally, it can be concluded that TQ could be used as a protective agent against TBHQ-induced cyto/genotoxicity in HUVECs