Evaluation of cell protection by Psephellus pyrrhoblepharus (Boiss.) Wagenitz extracts in MPP⁺-induced dopaminergic cell damage

Abstract

Neurodegenerative diseases affect millions of people. Major reasons behind the onset and progression of these diseases are still under investigation. Therefore, any approach that would treat/prevent progression is important. In this study, we aimed to investigate the potential protective effects of Psephellus pyrrhoblepharus (Boiss.) Wagenitz extracts in MPP⁺-induced dopaminergic cell damage and compare the effectiveness of different extracts (methanol:water (1:1), chloroform and n-hexane). The cells were pretreated with four different concentrations (10, 50, 100, and 200 µg/ml) of methanol:water (1:1), chloroform and n-hexane extracts of P. pyrrhoblepharus following MPP⁺ treatment for 12 or 24 h. The changes in cell viability were determined using the MTT assay. Additionally, antioxidant activities and total phenolic/flavonoid contents of the extracts were determined with radical scavenging capacity, Folin–Ciocalteu and aluminum chloride assays, respectively. The extracts at selected concentrations were found to be protective in a dose-dependent manner at 12 and 24 h. Nevertheless, the methanol extract of the plant showed the highest protection both at 100 and 200 µg/ml (115.13%±3.98, 121.87%±1.66; p < 0.05) against dopaminergic damage at 24 h. The results showed that selected concentrations were not toxic and did not affect cell proliferation rate. Besides, the chloroform extract was found to have higher antioxidant activity than the other extracts (p < 0.05). The total phenolic and total flavonoid contents were found consistent with antioxidant activities. Our findings support the neuroprotective and antioxidant potential of P. pyrrhoblepharus. However, further studies on identifying the presence of chemicals in P. pyrrhoblepharus extracts which are responsible for protection should be carried out to confirm their therapeutic potential.

Keywords:

• Psephellus pyrrhoblepharus
• antioxidant activity
• MPP⁺
• dopaminergic cell death
• neuroprotection

Acknowledgements

The authors acknowledge the Pharmaceutical Sciences Research Center (FABAL) of Faculty of Pharmacy, Ege University for equipment support. No animal or human studies were carried out by the authors.

Disclosure statement

The authors declare that they have no conflict of interest.