Planta Med 2006; 72 - P_031
DOI: 10.1055/s-2006-949831

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

AK Jäger 1, B Gauguin 1, L Gudiksen 1, A Adsersen 1
  • 1Department of Medicinal Chemistry, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK-2100 Copenhagen O, Denmark

Plant species used in Danish folk medicine to treat depression were selected based on the ethnobotanical standard work Folk og Flora [1]. Water and ethanol extracts of different plant parts from 18 plant species, resulting in 43 extracts, were tested for inhibition of MAO-A and affinity to the serotonin transporter. MAO-inhibitors and selective serotonin reuptake-inhibitors (SSRI) are clinically used to treat depression.

The MAO-A assay was performed in microtitre plates as a spectrophotometric peroxidase-linked assay measuring the production of a quinoneimine dye. The serotonin assay was performed as a binding assay using a rat brain homogenate with [3H]citalopram as ligand [2].

11 extracts had IC50 values below 0.025mg/mL extract (in total assay volume). The most active plant extracts in the MAO-A assay were the water extract of Hypericum perforatum L. (IC50 3.6µg/mL); ethanol extract of Trigonella foenum-graecum L. (IC50 3.6µg/mL); ethanol extract of Apium graveolens L. (IC50 4.8µg/mL) and the water extract of Calluna vulgaris (L.) Hull (IC50 8.5µg/mL)

In the serotonin transporter assay the most active extract was an ethanolic extract of aerial parts of Borago officinalis. The other extracts did not have affinity to the transporter.

References: 1. Brøndegaard, V.J. (1978), Folk og Flora. Vol. 1–4. Rosenkilde og Bagger, Denmark. 2. Nielsen, N.D. et al. (2004), J. Ethnopharmacol. 94: 159–163.