The Influence of Antioxidant Resveratrol on Paraquat-induced Oxidative Stress in Cultured Lung Cells

ABSTRACT

PURPOSE: Paraquat (1,1'-dimethy-4,4'-bipyridinium dichloride, PQ) is an effective and widely used herbicide, which was introduced commercially in 1962. It is reduced by an electron donor, such as NADPH, and then transfers the electron to molecular oxygen. As a result, the reactive oxygen species (ROS) produced are related to its cellular toxicity. Resveratrol (trans-3,4',5-trihydroxystilbene), a naturally occurring hydroxystilbene, is considered an essential antioxidative constituent of red wine, possessing chemopreventive properties. However, the influence of resveratrol on PQ-induced oxidative cell damage has not fully been investigated. METHODS: This experiment was conducted in vitro using cultured lung cells from SD rats. The MTT and LDH methods were used for assessment of cytotoxicity. The 2',7'-dichlorofluorescein diacetate (DCF-DA) assay was used for measurement of intracellular ROS levels. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was used for measurement of pro-oxidant capacity of resveratrol. The Thiobarbituric acid reactive substances (TBARS) assay, which reflects lipid peroxidation, was used for estimation of oxidative stress. RESULTS: According to results of the MTT and LDH assays, incubation of cultured lung cells with resveratrol did not protect lung cells from PQ-induced cytotoxicity, and no decrease in ROS production was observed, according to results of the DCF-DA assay. On the other hand, incubation of lung cells with non-lethal resveratrol resulted in aggravation of PQ-induced oxidative stress. CONCLUSION: Results of this study showed that incubation of cells with resveratol did not result in reduction of PQ toxicity, but lead to elevation of PQ-induced oxidative stress in cultured lung cells.