Protective effects of ginsenoside Re on the dopaminergic neurons in the MPTP-induced mouse model of PD

Objective To investigate the protective effect of ginsenoside Re on dopaminergic neurons and its mechanisms in 1-methy-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced mouse's model of the Parkinson's disease (PD).Method C57BL mice were administrated i.s.c with MPTP to establish PD model.The pretreatment groups were given different doses of ginsenoside Re (6.5,13, 26 mg·kg -1) i.g.for 13 days.Tyrosine hydroxylase (TH) and γ-aminobutyric acid(GABA) expressions were investigated by the immunohistochemistry (ICC) method.RT-PCR was used to detect the expression of PPD mRNA and PPE mRNA.Result The pretreatment with ginsenoside Re (13, 26 mg·kg -1) is shown to markedly increase TH-positive neurons in the SNc and GABA-positive neurons in SNr.Simultaneously,Re is found to up-regulate expression of PPD mRNA (P0.05) compared with the model group.Conclusion Ginsenoside Re shows protective effects on dopaminergic neurons in the MPTP-induced mouse's model of PD.It may relate to changing the expression of GABAergic neurons and PPD mRNA and regulating the balance of excitation and inhibition between the direct circuit and indirect circuit by Re.