Acanthopanax senticosus Harms as a prophylactic for MPTP-induced Parkinson's disease in rats.

The aim of this study was to determine whether Acanthopanax senticosus Harms (ASH) offers protection against Parkinson's disease (PD) and its related depressive behaviors in rats administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). We examined how ASH affected the MPTP-induced loss of tyrosine hydroxylase (TH)-positive neurons in the midbrain of rats. Extract from the stem bark of ASH prepared with hot water was dissolved in distilled water. Rats were then orally administered ASH (250 mg/kg) once a day for 2 weeks before ASH administration plus an intraperitoneal injection of MPTP (20 mg/kg). The pole test and catalepsy test were used to evaluate the effects of ASH administration on bradykinesia and depressive behaviors in the PD model of rats given MPTP for 2 weeks. Treatment with ASH for 2 weeks resulted in prophylactic effects on MPTP-induced Parkinsonian bradykinesia and catalepsy. Immunohistochemistical analysis using TH antibody showed that ASH provided cytoprotective effects against MPTP-induced loss of dopamine (DA) cells. The present results suggest that it may be possible to use ASH for the prevention of nigral degenerative disorders, e.g., PD with depression, caused by exposure to toxic substances.