Parkinson's disease (PD) is a
neurodegenerative disorder characterized by the irreversible loss of dopaminergic neurons in the nigrostriatal pathway with subsequent
dopamine deficiency. Environmental causes have been proposed through molecules, such as
1-methyl-4-phenylpyridinium (MPP(+)), to induce oxidative stress. The methanolic extract of plants of the genus Buddleja has been reported to have in vitro and in vivo
antioxidant properties to protect against neuronal death. In the present study, the
neuroprotective effect of Buddleja cordata methanolic extract in the MPP(+) PD rat model was investigated. Animals were administered orally with 50 or 100 mg/kg of methanolic extract every 24 h for 14 days. Twenty hours later, rats were infused with an intrastriatal stereotaxic microinjection of 10 µg MPP(+) in 8 μl sterile
saline solution. Six days later, the animals were treated with 1 mg/kg
apomorphine to record ipsilateral rotations for 1 h. All the rats were killed by
decapitation and the lesioned striatum was dissected for
dopamine and lipid peroxidation quantifications. Both methanolic extract doses led to a significantly lower (P < 0.05) number of ipsilateral rotations (75-80 %). This behavioral protection was corroborated with 60 % level of
dopamine preservation (P < 0.05) and 90 % decrease in the formation of lipidic fluorescent products in the striatum (P < 0.05). This study demonstrates the
antioxidant and
neuroprotective effect of Buddleja cordata methanolic extract in the MPP(+) PD rat model, possibly due to the involvement of phenylpropanoids.