Zebrafish-based evaluation of antiepileptic activity of Pimpinella major (L.) Huds. and its main constituent pimpinellin

Epilepsy represents the most common chronic neurological disorder with diverse etiology, affecting at least 70 million people worldwide. Taking into consideration that the antiepileptic drugs (AEDs) are effective in only 70% of the patients, the discovery of new AEDs with novel mechanisms of action is a very important task. There is a large body of literature reporting research on the antiepileptic effects of plants, with several plant-derived compounds, such as cannabidiol, cannabidivarin and huperzine currently under development as AEDs [1],[2].

The aim of this study was to perform an initial zebrafish-based evaluation of the antiepileptic activity of Pimpinella major (L.) Huds. (Apiaceae), plant used in traditional medicine for treating mental disorders, and isolate its main active constituents. The methanolic root extract of P. major was screened in a zebrafish epilepsy model based on the GABA_A antagonist pentylenetetrazol (PTZ), which induces an increased locomotor activity, seizure-like behavior and epileptiform electrographic activity in zebrafish larvae [3].

At 10 μg/mL, the extract decreased PTZ-induced locomotor activity by 45.87%. As a purification tool that enables fast and effective separation of compounds, high-performance countercurrent chromatography (HPCCC) led to the isolation of pimpinellin (16 mg, purity > 98%) from 738 mg of crude extract in 30 minutes. Additionally, three other coumarin derivatives were isolated and tested. Of these, pimpinellin (60 μM) was able to potently decrease PTZ-induced locomotor activity by 63.79%. Thus, the HPCCC and zebrafish epilepsy model could be used as efficient platform for the fast identification and isolation of compounds with promising antiepileptic activity.

Acknowledgments

Preludium11 grant 2016/21/N/NZ4/03658 from the National Science Center (NCN) of Poland.

• References

• 1 Sucher NJ, Carles MC. A pharmacological basis of herbal medicines for epilepsy. Epilepsy Behav 2015; 52: 308-318
• 2 Koziol. et al High-performance counter-current chromatography isolation and initial neuroactivity characterization of furanocoumarin derivatives from Peucedanum alsaticum L (Apiaceae). Phytomedicine 2019; 54: 259-264
• 3 Afrikanova. et al. Validation of the zebrafish pentylenetetrazol seizure model: locomotor versus electrographic responses to antiepileptic drugs. PLoS ONE 2013; 8: e54166