Planta Med 2006; 72(3): 211-216
DOI: 10.1055/s-2005-916195
Original Paper
Pharmacology
© Georg Thieme Verlag KG Stuttgart · New York

Intestinal Absorption of Stemona Alkaloids in a Caco-2 Cell Model

Pak Ho Henry Leung1 , Li Zhang2 , Zhong Zuo2 , Ge Lin1
  • 1Department of Pharmacology, The Chinese University of Hong Kong, Shatin, N. T., Hong Kong, SAR
  • 2School of Pharmacy, The Chinese University of Hong Kong, Shatin, N. T., Hong Kong, SAR
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Publikationsverlauf

Received: June 3, 2005

Accepted: August 10, 2005

Publikationsdatum:
05. Dezember 2005 (online)

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Abstract

The intestinal absorption of neotuberostemonine and neostenine, two major bioactive alkaloids of the commonly used antitussive traditional Chinese medicine Stemona tuberosa Lour, was investigated using a Caco-2 monolayer model. Both alkaloids exhibited a high absorptive permeability which was higher for neostenine [Papp(AB) = 12.03 ± 1.14 × 10 - 6 cm/s] than for neotuberostemonine [Papp(AB) = 9.27 ± 0.79 × 10 - 6 cm/s], indicating that they are likely to be well absorbed and orally active. Furthermore, both alkaloids were identified to be the substrates of P-glycoprotein and have a transport preference from the basolateral to apical direction with efflux ratios between 2 and 3. Cyclosporin A dose-dependently inhibited the secretory permeability of these alkaloids and abolished their active efflux transport.