Cirsium japonicum var. maackii inhibits hydrogen peroxide-induced oxidative stress in SH-SY5Y cells

Abstract

Over-produced reactive oxygen species (ROS) exert oxidative damage on lipids, proteins, and DNA in the human body, which leads to the onset of neurodegenerative diseases such as Alzheimer’s disease (AD). In this study, we explored the cellular antioxidant effect of Cirsium japonicum var. maackii (CJM) against hydrogen peroxide (H2O2)-induced oxidative stress in neuronal cells. The antioxidant activity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, 2',7'-dichlorofluorescin diacetate and nitric oxide (NO) assays, and the molecular mechanisms were examined by Western blot analysis. H2O2 treatment of SH-SY5Y cells decreased cell viability and increased ROS and NO production compared to H2O2-untreated cells. However, CJM increased cell viability and decreased ROS and NO accumulation in the H2O2-treated SH-SY5Y cells compared to H2O2-treated control cells. Especially, the EtOAc fraction from CJM showed the strongest antioxidant effect compared with the other extracts and fractions. Therefore, we further examined the CJM mechanism against oxidative stress using the EtOAc fraction from CJM. The EtOAc fraction up-regulated the expressions of heme oxygenase-1, NAD(P)H quinone oxidoreductase 1, and thioredoxin reductase 1. These results indicate that CJM promotes the activation of antioxidative enzymes, which eliminate ROS and NO, and further leads to an increase in the cell viability. Taken together, our results show that CJM exhibited an antioxidant activity in H2O2-treated SH-SY5Y cells, and it could be a novel antioxidant agent for the prevention or treatment of neurodegenerative disease such as AD.