Paraquat Induced Nigrostriatal Dopaminergic Degeneration And Neuroprotective Effects Of Polygonum Multiflorum

Parkinson's disease (PD) is a slowly progressive disorder that affects movement, muscle control and balance. PD is referred to as idiopathic, which means that the cause is unknown. This term distinguishes the primary disease from parkinsonism, which are the symptoms occurring from a known cause. Paraquat( 1,1'-dimethyl-4,4'-bipyridinium, PQ), a widely used herbicide, bearing structural similarity to the known dopaminergic neurotoxicant MPTP, has been suggested as a potential etiologic factor for the development of PD. Polygonum multiflorum Thunb (PM) is a medicinal herb which has long been used as a constituent of traditional Chinese prescriptions aiming at treatment of the aging-related diseases such as cognitive impairment and PD. In this studay, we investigated nigrostriatal dopaminergic degeneration induced by PQ and a combination of paraquat and maneb (PQMB) and neuroprotective effects of Polygonum multiflorum on nigrostriatal dopaminergic neurons induced by PQMB in C57BL/6 mice.1. Cytotoxic effect of PQ on PC12 cellsCytotoxic effects of PQ on PC12 cells were investigated in this study. PC12 cells were incubated with PQ (0.13 mM) for 4 h,8 h,12 h, 24 h; PC12 cells were exposed in increasing PQ concentrations (0.016-0.26 mM) for 12 h. Cell viability was measured using thiazolyl blue (MTT) method. The cytotoxic effects were dose-dependent and time-dependeent. In present experiment, ascorbic acid (AA) (0.1 μM ,1 μ M, 10μM) incubated with PC12 cells for 3 h in advance could attenuate PC12 cells injuries induced by PQ. To investigate the effect of dopamine(DA) on PC1 2 cells, PC12 cells were...