20C,a bibenzyl compound isolated from Gastrodia elata,possesses antioxidative properties in PC12 cells,but its in-depth molecular mechanisms against rotenone-induced neurotoxicity remains unknown.Recent studies indicate that without intact DJ-1,nuclear factor erythroid 2-related factor(Nrf2)protein becomes unstable,and the activity of Nrf2-mediated downstream antioxidant enzymes are thereby suppressed.Therefore,increasing the nuclear translocation of Nrf2 by DJ-1 may present a helpful means for the prevention and treatment of chronic diseases related to oxidative stress.Our results showed that 20C clearly protected PC12 and SH-SY5Y cells against rotenone-induced oxidative injury in a concentration-dependent manner.Furthermore,20C markedly up-regulated the levels of DJ-1,which in turn activated phosphoinositide-3-kinase(PI3K)/Akt signaling and inhibited glycogen synthase kinase 3β(GSK3β)activation,eventually promoting Nrf2 nuclear translocation and inducing the expression of Nrf2-mediated downstream antioxidative enzymes such as HO-1.The antioxidative effects of 20C could be partially blocked by ShR NA-mediated knockdown of DJ-1 and inhibition of the PI3K/Akt pathways with Akt1/2 kinase inhibitor in PC12 and SH-SY5Y cells,respectively.Conclusively,our findings confirm that DJ-1 is necessary for 20C-mediated protection against rotenone-induced oxidative damage,at least in part,by activating PI3K/Akt signaling,and subsequently enhancing the nuclear accumulation of Nrf2.The findings from our investigation suggest that 20C should be developed as a novel candidate for preventing or alleviating the consequences of PD in the future. 20C, a bibenzyl compound isolated from Gastrodia elata, possesses antioxidant properties in PC12 cells, but its in-depth molecular mechanisms against rotenone-induced neurotoxicity remains. Unknown studies indicate that without intact DJ-1, nuclear factor erythroid 2-related factor Nrf2) protein becomes unstable, and the activity of Nrf2-mediated downstream antioxidant enzymes are hereby suppressed. Herefore, increasing the nuclear translocation of Nrf2 by DJ-1 may present a helpful means for the prevention and treatment of chronic diseases related to oxidative stress. Our results showed that 20C clearly protected PC12 and SH-SY5Y cells against rotenone-induced oxidative injury in a concentration-dependent manner. Futuremore, 20C markedly up-regulated the levels of DJ-1, which in turn activated phosphoinositide-3-kinase PI3K) / Akt signaling and inhibited glycogen synthase kinase 3β (GSK3β) activation, eventually promoting Nrf2 nuclear translocation and inducing the expression of Nrf2-medi ated downstream antioxidative enzymes such as HO-1. The antioxidative effects of 20C could be partially blocked by ShR NA-mediated knockdown of DJ-1 and inhibition of the PI3K / Akt pathways with Akt1 / 2 kinase inhibitor in PC12 and SH-SY5Y cells , respectively. Confclusively, our findings confirm that DJ-1 is necessary for 20C-mediated protection against rotenone-induced oxidative damage, at least in part, by activating PI3K / Akt signaling, and subsequently enhancing the nuclear accumulation of Nrf2. findings from our investigation suggest that 20C should be developed as a novel candidate for preventing or alleviating the consequences of PD in the future.