Modulation of GABAA-receptors by honokiol and derivatives: subtype selectivity and structure-activity relationship.

Author(s)
Barbara Taferner, Wolfgang Martin Schühly, Antje Hüfner, Igor Baburin, Katharina Wiesner, Gerhard Ecker, Steffen Hering
Abstract

A series of 31 analogues of the neolignan honokiol (a major constituent of Magnolia officinalis) was synthesized, and their effects on GABA(A) receptors expressed in Xenopus oocytes were investigated. Honokiol enhanced chloride currents (I(GABA)) through GABA(A) receptors of seven different subunit compositions with EC(50) values ranging from 23.4 uM (a(5)b(2)) to 59.6 uM (a(1)b(3)). Honokiol was most efficient on a(3)b(2) (maximal I(GABA) enhancement 2386%) > a(2)b(2) (1130%) > a(1)b(2) (1034%) > a(1)b(1) (260%)). On a(1)b(2)-receptors, N-substituted compounds were most active with 3-acetylamino-4'-O-methylhonokiol (31), enhancing I(GABA) by 2601% (EC(50) (a(1)b(2)) = 3.8 uM). Pharmacophore modeling gave a model with an overall classification accuracy of 91% showing three hydrophobic regions, one acceptor and one donor region. Unlike honokiol, 31 was most efficient on a(2)b(2)- (5204%) > a(3)b(2)- (3671%) > a(1)b(2)-receptors (2601%), suggesting a role of the acetamido group in subunit-dependent receptor modulation.

Organisation(s)
External organisation(s)
Karl-Franzens-Universität Graz
Journal
Journal of Medicinal Chemistry
Volume
54
Pages
5349-5361
No. of pages
13
ISSN
0022-2623
DOI
https://doi.org/10.1021/jm200186n
Publication date
2011
Peer reviewed
Yes
Austrian Fields of Science 2012
301206 Pharmacology
Portal url
https://ucrisportal.univie.ac.at/en/publications/c6256f70-d570-459a-b48e-fbb530e7049b