α-Cyperone protects dopaminergic neurons and inhibits neuroinflammation in LPS-induced Parkinson’s disease rat model via activating Nrf2/HO-1 and suppressing NF-κB signaling pathway

Our previous study showed that α-Cyperone inhibited the inflammatory response triggered by activated microglia and protected dopaminergic neuron in in vitro cell model of Parkinson's disease (PD). It is unclear the effect of α-Cyperone in animal models of PD. In this study, our results indicated that α-Cyperone ameliorated motor dysfunction, protected dopaminergic neurons, and inhibited the reduction of dopamine and its metabolites in lipopolysaccharide (LPS)-induced PD rat model. Moreover, α-Cyperone suppressed the activation of microglia and the expression of neuroinflammatory factor (TNF-α, IL-6, IL-1β, iNOS, COX-2 and ROS). Furthermore, the molecular mechanism research revealed that α-Cyperone inhibited neuroinflammation and oxidative stress to exert protective effect in microglia by activating Nrf2/HO-1 and suppressing NF-κB signaling pathway. Moreover, α-Cyperone upregulated the expression of antioxidant enzymes (GCLC, GCLM and NQO1) in microglia. In conclusion, our study demonstrates α-Cyperone alleviates dopaminergic neurodegeneration by inhibiting neuroinflammation and oxidative stress in LPS-induced PD rat model via activating Nrf2/HO-1 and suppressing NF-κB signaling pathway.