Neuroprotective Effect of Quercetin in a Model of Parkinson’s Disease in Rat: A histochemical Analysis

Introduction: Parkinson’s disease (PD) is a neuropathological disorder involving the degeneration of dopaminergic neurons in the substantia nigra, with the subsequent loss of their terminals in the striatum. Quercetin, a natural flavonoid, is a strong antioxidant and radical scavenger. Therefore, its neuroprotective effect in a model of Parkinson’s disease in rat was evaluated. Methods: For this purpose, unilateral intrastriatal 6- hydroxydopamine (6-OHDA) -lesioned rats were pretreated with quercetin (20 mg/kg; i.p.) 1 hour before surgery and treated once a day for one month. Nissl-stained neurons of substantia nigra pars compacta (SNC) were counted. Results: Number of Nissl-stained neurons in left side of SNC of lesion group was lower relative to sham-operated group (p 0.005) and it was higher in quercetin-treated lesion group as compared to untreated lesion group (p 0.01). Discussion: Flavonoid quercetin administration for one month could protect the neurons of SNC against 6-OHDA toxicity.