Effects of DHF on oxidative stress in MPTP-induced Parkinson's disease model mice

Zonggang Zhao^{1, #}, Shengnan Wang^{2, #}, Xinxin Wang¹, Lanlan Sun^{3, *}

¹Department of Neurology, the Fifth People's Hospital of Jinan, Jinan 250022, PR China - ²Department of Physical Examination Center, the Fifth People's Hospital of Jinan, Jinan 250022, PR China - ³Department of Hematology, the First Affiliated Hospital of Shandong First Medical University, Jinan 250022, PR China

Objective: To investigate the effects of 7,8-dihydroxyflavone (DHF) on oxidative stress in Parkinson's disease (PD) model mice induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). 

Methods: Forty-five clean-grade, male C57BL/6 mice were randomly selected and fed for 1 week. Mice were randomly divided into a control group, model group, and DHF group, with 15 mice in each group. A PD mouse model was established and the rotating rod experiment, climbing rod experiment, and suspension experiment were conducted on each group. Immunohistochemical staining was performed to evaluate the number of tyrosine hydroxylase (TH)-positive neurons in the substantia nigra of mice in each group. The expression of α-synuclein (α-syn) in the brain tissue was detected by Western blotting. The levels of catalase (CAT), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) were also measured. 

Results: Compared with the control group, the mice in the model group stayed on the roller for significantly shorter periods and took a significantly longer time to climb down the cylinder and onto the platform (P < 0.05). The mice in the DHF group stayed on the roller for significantly longer periods than the model group and required a significantly shorter time to climb down the cylinder and onto the platform (P < 0.05). Compared with the control group, the number of TH-positive neurons in the substantia nigra of the model group was significantly reduced (P < 0.05) and the corresponding number in the DHF group was significantly increased (P < 0.05). The expression level of α-syn in the brain tissue of the model group was significantly higher than that of the control group (P < 0.05), and the expression level of α-syn in the brain tissue of the DHF group was significantly lower than that of the model group (P < 0.05). Compared with the control group, the levels of CAT, GSH-Px, and SOD in the brain tissue of the model group were significantly lower and the levels of MDA were significantly higher. Compared with the model group, the levels of CAT, GSH-Px, and SOD in the brain tissue of the DHF group were significantly higher, while the levels of MDA were significantly lower (P < 0.05). 

Conclusion: DHF can significantly improve motor dysfunction in PD mice and alleviate the injury caused by oxidative stress.