Short Lecture “Assessing the neuroactive potential of botanical extracts using novel in vitro methods”

Due to their neuroactive properties, botanicals are often used to preserve and enhance human health and well-being. However, safety evaluations of botanicals are often inadequate and there is an urgent need to screen botanicals for their possible adverse effects.

Costly and ethically-debated animal experiments to investigate neurotoxicity are increasingly replaced with in vitro methods, for example using microelectrode array (MEA) recordings to measure changes in neuronal function. Rat primary cortical cultures consist of different types of neurons and supportive cells. The presence of multiple cell types and targets ensures that cortical cultures grown on MEAs are sensitive to many different toxicological pathways by which botanicals can alter physiological function. Moreover, these recordings can be multiplexed with cell viability to aid in prioritisation of botanicals for in-depth analysis.

As part of a cross-sector collaboration of the Botanical Safety Consortium (BSC, a public-private partnership formed by the US-FDA, NIEHS, and HESI), we evaluated the suitability of MEA recordings for neurotoxicity screening of botanical extracts.

Acute (30 min) exposure of cortical cultures to aconite extract (5-50 µg/mL) evoked an intense hyperexcitation, with mean spike rate (MSR), mean burst rate (MBR) and mean network burst rate (MNBR) increased to 230-700%. Contrary, extracts from kava and kratom resulted in a dose-dependent decrease in neuronal activity, whereas ginseng extract was largely inactive (up to 50 µg/mL).

These results provide an important first step in the in vitro safety evaluation of botanical extracts.

 

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Conflict of Interest

The authors declare no conflict of interest.

Publication History

Article published online:
16 November 2023