Cytoprotective effect of fucoxanthin isolated from brown algae Sargassum siliquastrum against H2O2-induced cell damage

In this study, the cytoprotective effect of fucoxanthin, which was isolated from Sargassum siliquastrum, against oxidative stress induced DNA damage was investigated. Fucoxanthin, a kind of carotenoid, was pretreated to the medium and the protective effect was evaluated via 2',7'-dichlorodihydrofluorescein diacetate, 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide, and comet assays. Intracellular reactive oxygen species were over produced by addition of hydrogen peroxide (H2O2), but the production was significantly reduced by the treatment with fucoxanthin. The fucoxanthin strongly enhanced cell viability against H2O2 induced oxidative damage and the inhibitory effect of cell damage was a dose-dependent manner. Furthermore, a protective effect against oxidative stress-induced cell apoptosis was also demonstrated via nuclear staining with Hoechst dye. These results clearly indicate that fucoxanthin isolated from S. siliquastrum possesses prominent antioxidant activity against H2O2-mediated cell damage and which might be a potential therapeutic agent for treating or preventing several diseases implicated with oxidative stress.