Screening of plants used in Danish folk medicine to treat depression and anxiety for affinity to the serotonin transporter and inhibition of MAO-A

Abstract

Ethnopharmacological relevance: A number of plant species are used in Danish folk medicine for treatment of depression and anxiety.

Materials and methods: Aqueous and ethanolic extracts of 17 plant species were tested for affinity to the serotonin transporter and for inhibition of MAO-A-both targets for antidepressive treatment.

Results: An ethanolic extract of aerial parts of Borago officinalis had affinity to the serotonin transporter. Ten extracts, from eight plants, had IC(50) values below 25μg/ml extract in the MAO-A assay. The most active extracts in the MAO-A assay were the ethanol extract of seeds of Trigonella foenum-graecum (IC(50) 4μg/ml); ethanol extract of leaves of Apium graveolens (IC(50) 5μg/ml) and the water extract of aerial parts of Calluna vulgaris (IC(50) 8μg/ml).

Conclusions: Besides Borago officinalis, which toxicity profile excludes it from further development as an herbal drug, none of the plants had potential as serotonin reuptake inhibitors. Several plants had MAO-A inhibitory activity.