Neuroprotective and neurorescue effects of eggplant extract in 6-OHDA-induced Parkinson’s rat model

Objective: Parkinson’s disease (PD) is one of the most common progressive neurodegenerative disorders. Though the exact etiology of PD is largely unknown, oxidative stress has been reported to play an important role in PD. Nowadays, natural products have gained attention as an alternate therapy to delay the onset of neurodegeneration. The aim of the current study was to assess the neuroprotective and neurorescue potential of Eggplant (Solanum melongena L) Extract (EE) in 6-OHDA-induced Parkinsonian rat model. Materials and methods: The filtered crude extract of eggplant fruit was prepared and their total flavonoids content was analysed by aluminium chloride (AlCl3) method. Free radical scavenging activity was determined by DPPH assay. Neuroprotective activity was performed on Wistar healthy male models. Phytochemical analysis was carried out by LC/MS analysis. Results: Our results indicated the presence of substantial amounts of phenolics and flavonoids in EE, suggestive of potent free radical scavenging activity. Antioxidant assays revealed that EE exhibits significant ROS scavenging activity. Neurobehavioral analysis showed corrected circling behaviour induced by D-amphetamine and spontaneous locomotor activity in the animals that received EE before or after the 6-OHDA lesioning. Treatment of EE before or after the 6-OHDA lesioning significantly restored the altered levels of oxidative markers in the substantia nigra as well as levels of antioxidant enzymes in the striatum regions of rat brain. Additionally, EE also restored levels of dopamine and dihydroxyphenyl acetic acid and increased expression of tyrosine hydroxylase in the ipsilateral striatum region of the 6-OHDA intoxicated rat brain. Finally LC/MS analysis of the extract revealed the presence of several flavonoids such as kaempferol, quercetin, naringenin and phenolics such as gallic acid, caffeoyl putrescine, and 5-caffeoylquinic acid. Conclusion: Taken together, our findings indicate that the EE has both neuroprotective as well as neurorescue effects in 6-OHDA-induced Parkinson’s in rat model which could potentially be due to the presence of antioxidant flavonoids and phenolics.