Eupatilin prevents behavioral deficits and dopaminergic neuron degeneration in a Parkinson's disease mouse model

Aims: Neuroinflammation and apoptosis play a crucial role in Parkinson's disease (PD) pathogenesis. Eupatilin is a lipophilic flavonoid isolated from Artemisia species and exerts anti-apoptotic and anti-inflammatory activities. In this study, we investigated the effects of Eupatilin on a mouse model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Main methods: The rotarod test and traction test were constructed to examine the motor function. Immunofluorescent staining was performed to detect the expression of TH, Iba-1 and GFAP. Apoptosis was examined by the TUNEL assay. Real-time PCR was used to determine the mRNA expression and Western blot and ELISA were used to determine the protein expression. Key findings: Eupatilin improved behavioral impairment caused by MPTP. A loss of TH positive neurons was observed in the substantia nigra pars compacta of MPTP-lesioned brain, while it was rescued by Eupatilin. Moreover, MPTP administration increased the cell number of microglia and astrocytes and the expression of inflammatory factors TNF-alpha, IL-1 beta, and IL-6. Whereas Eupatilin suppressed the activation of neuroinflammation. Eupatilin also decreased cell apoptosis enhanced by MPTP/MPP+ exposure in vivo and in vitro. We further revealed that Eupatilin abolished MPTP-induced downregulation of I kappa B alpha expression and accumulation of p65 in the nuclear compartment. Besides, MPTP administration led to dephosphorylation of Akt and GSK-3 beta, but it was restored by Eupatilin. Significance: We demonstrate that Eupatilin alleviates behavioral impairment and dopaminergic neuron loss induced by MPTP through inhibition of neuroinflammation and apoptosis. Our research provides more evidence for Eupatilin as a potential preventative drug for PD.