| Abstract: Objective: To investigate the effects of quercetin (QUE) on behavioral disorders and nuclear factor erythroid 2-related factor 2-antioxidant response element (Nrf2-ARE) signaling pathway in Parkinson's syndrome (PD) mice. Methods: BALB/c mice were randomly divided into control group (Control group), PD group, QUE low dose group (QUE-L group), QUE high dose group (QUE-H group), QUE high dose+pathway inhibitor ML385 group (QUE-H+ML385 group), 18 mice in each group. At the end of administration, the behavior of BALB/c mice was detected. The levels of oxidative stress [malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px)] were detected by enzyme-linked immunosorbent assay. The pathological changes of substantia nigra in brain tissue were observed by hematoxylin-eosin (HE) staining. The survival of neurons was observed by Nissl staining. The expression of tyrosine hydroxylase (TH) and α-synuclein (α-syn) in the substantia nigra was detected by immunohistochemistry. The expression of Nrf2-ARE signaling pathway-related proteins was detected by western blot. Results: The arrangement of dopaminergic neurons in the substantia nigra of PD group was disordered compared with Control group, the number of neurons was reduced and the cell body was shrunk, the number of Nissl bodies was reduced, the mouse suspension test score was reduced, the roller balance time was shortened, the balance rod time was prolonged, the MDA level and the expression of α-syn were increased, the levels of SOD, GSH-Px and the expression of tyrosine hydroxylase (TH), Nrf2 and quinone oxidoreductase (NQO1) were decreased (P<0.05); The arrangement of dopaminergic neurons in the substantia nigra of QUE-L and QUE-H groups was relatively orderly compared with PD group, the number of neurons was increased and the morphology was relatively normal, the number of Nissl bodies was increased, the suspension test score was increased, the balance time of the roller was prolonged, the balance rod time was shortened, the MDA level and the expression of α-syn were decreased, the levels of SOD, GSH-Px and the expression of TH, Nrf2 and NQO1 were increased (P<0.05). The arrangement of dopaminergic neurons in QUE-H+ML385 group was disordered compared with QUE-H group, the number of neurons decreased significantly and the morphology was abnormal, the number of Nissl bodies decreased significantly, the score of suspension test in mice decreased, the balance time of roller decreased, the time of over-balance rod prolonged, the level of MDA and the expression of α-syn increased, and the levels of SOD and GSH-Px and the expression of TH, Nrf2 and NQO1 decreased (P<0.05). Conclusion: QUE can improve the motor behavior disorder of PD mice, which may be related to the activation of Nrf2-ARE signaling pathway. |