Insights into structure-activity relationship of GABAA receptor modulating coumarins and furanocoumarins.
- Author(s)
- Judith Singhuber, Igor Baburin, Gerhard Ecker, Brigitte Kopp, Steffen Hering
- Abstract
The coumarins imperatorin and osthole are known to exert anticonvulsant activity. We have therefore analyzed the modulation of GABA-induced chloride currents (I(GABA)) by a selection of 18 coumarin derivatives on recombinant a(1)b(2)g(2S) GABA(A) receptors expressed in Xenopus laevis oocytes by means of the two-microelectrode voltage clamp technique. Osthole (EC(50)=14 ± 1 uM) and oxypeucedanin (EC(50)=25 ± 8 uM) displayed the highest efficiency with I(GABA) potentiation of 116 ± 4 % and 547 ± 56 %, respectively. I(GABA) enhancement by osthole and oxypeucedanin was not inhibited by flumazenil (1 uM) indicating an interaction with a binding site distinct from the benzodiazepine binding site. In general, prenyl residues are essential for the positive modulatory activity, while longer side chains or bulkier residues (e.g. geranyl residues) diminish I(GABA) modulation. Generation of a binary classification tree revealed the importance of polarisability, which is sufficient to distinguish actives from inactives. A 4-point pharmacophore model based on oxypeucedanin - comprising three hydrophobic and one aromatic feature - identified 6 out of 7 actives as hits. In summary, (oxy-)prenylated coumarin derivatives from natural origin represent new GABA(A) receptor modulators.
- Organisation(s)
- Journal
- European Journal of Pharmacology
- Volume
- 668
- Pages
- 57-64
- No. of pages
- 8
- ISSN
- 0014-2999
- Publication date
- 2011
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 301206 Pharmacology, 106005 Bioinformatics, 301204 Pharmacognosy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/63a0fce0-dcfa-4dbe-99a7-30fa1e68b1d8