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Planta Med 2012; 78(5): 440-447
DOI: 10.1055/s-0031-1298229
Biological and Pharmacological Activity
Original Papers
© Georg Thieme Verlag KG Stuttgart · New York

HPLC-based Activity Profiling – Discovery of Sanggenons as GABAA Receptor Modulators in the Traditional Chinese Drug Sang bai pi (Morus alba Root Bark)

Hyun Jung Kim1 [*] , Igor Baburin2 [*] , Janine Zaugg1 , Samad Nejad Ebrahimi1 , 3 , Steffen Hering2 , Matthias Hamburger1
  • 1Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland
  • 2Institute of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
  • 3Department of Phytochemistry, Medicinal Plant and Drugs Research Institute, Shahid Beheshti University, G. C., Tehran, Iran
Further Information

Publication History

received October 10, 2011 revised Dec. 5, 2011

accepted Dec. 30, 2011

Publication Date:
31 January 2012 (online)

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Abstract

EtOAc extracts from two batches of Morus alba root bark (Sang bai pi) potentiated γ-aminobutyric acid (GABA)-induced chloride influx in Xenopus oocytes, which transiently expressed GABAA receptors of the subunit composition α 1 β 2 γ 2S. With the aid of HPLC-based activity profiling of the extract from the first batch, activity was traced to a peak subsequently identified as sanggenon G (3). The second batch had a different phytochemical profile, and HPLC-based activity profiling led to the identification of sanggenon C (4) and a stereoisomer of sanggenon D (2) as positive GABAA receptor modulators. The structurally related compound kuwanon L (1) was inactive. The sanggenons represent a new scaffold of positive GABAA receptor modulators.

Key words

GABAA receptor modulator - Xenopus oocytes - HPLC-based activity profiling - sanggenon - Morus alba - Moraceae

Supporting Information

References

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1 These authors contributed equally to this work.

Prof. Matthias Hamburger

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University of Basel

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