Protective effect of Korean ginseng berry on hydrogen peroxide (H2O2)-induced oxidative damage in SH-SY5Y cells

It has been known that the ginseng berry contains nutrients higher than roos of ginseng, and has higher ginsenoside content than of the root. However, until now, many studies have focused on the effect of the ginseng root. This study investigated the effect of Korean ginseng berry extract (KGB) on hydrogen peroxide (H₂O₂)-induced neuronal damage and potential mechanisms in human SH-SY5Y neuroblastoma cells. Our results revealed that pretreatment with KGB dose-dependantly inhibited H₂O₂-induced apoptotic cell death, which was measured by MTT assay and Hoechst 33342 staining. H₂O₂-induced increases of reactive oxygen species (ROS) generation and mitochondrial dysfunction were attenuated by KGB pretreatment. KGB effectively suppressed the up-regulation of Bax and down-regulation of Bcl-2, and caspase-3 activation. KGB also blocked the H₂O₂-induced phosphorylation of mitogen-activated protein kinases (MAPK) including extracellular signal-regulated protein kinase 1/2 (ERK 1/2), c-Jun N-terminal protein kinase (JNK), and p38. H₂O₂-induced induction of HSP70 was enhanced by KGB. Moreover, KGB enhanced the activities of antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), and decreased the malondialdehyde (MDA) content. These results show that KGB has a protective effect against H₂O₂-induced oxidative stress in SH-SY5Y cells via the inhibiting of MAPK signalling pathway and enhancing HSP70 production. Therefore, KGB may be development potential as a preventive and therapeutic agent for neurodegenerative diseases and other disorders caused by oxidative stress.