Is arbutin an effective antioxidant for the discount of oxidative and nitrosative stress in Hep-G2 cells exposed to tert-butyl hydroperoxide?

Oxidative and nitrosative stress triggers an extensive damage to the tissues. Many herbal and chemical medicines have claimed to possess antioxidant properties. Arbutin exists in some plants such as Pyrus Biossierana Bushe. In this study, an inhibitory effect of arbutin against tert-butyl hydroperoxide induced cytotoxicity was studied using SYTOX TM Green assay for cell viability. The antioxidant effects of arbutin on the generation of malondialdehyde, nitric oxide, activity of oxidative enzyme (Superoxide dismutase and catalyze) and the amount of total thiol in Hep-G2 cells exposed to tert-butyl hydroperoxide were evaluated.Hep-G2 cells were cultured in 24-well plates. After 24 hours, the cells were pretreated with the arbutin at different concentrations (0, 100 and 150 µM). 24 hours later, tert-butyl hydroperoxide at different concentrations (0, 150, 200 and 250 µM) was added into the culture media.Arbutin was able to decrease malondialdehyde and nitric oxide concentrations in arbutin treated group in comparison with the control group (p < 0.00001). The catalase and superoxide dismutase enzymes in these cells were significantly decreased in a dose depend manner in the presence of arbutin in comparison with the control group (p < 0.00001). In addition, arbutin was capable of increasing the tert-butyl hydroperoxide mediated reduction in the total thiol amount in comparison with the control group (p < 0.00001.) CONCLUSION: Our investigation demonstrated that tert-butyl hydroperoxide evoked a reactive oxygen and nitrogen species overproduction in Hep-G2 cells. The cells treated with arbutin showed a dose-dependent reduction of tert-butyl hydroperoxide induced reactive oxygen and nitrogen species generation (Fig. 6, Ref. 34).