Intestinal absorption of Stemona alkaloids in a Caco-2 cell model.
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 [P(app(AB)) = 12.03 +/- 1.14 x 10 (-6) cm/s] than for neotuberostemonine [P(app(AB)) = 9.27 +/- 0.79 x 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.
Department of Pharmacology, The Chinese University of Hong Kong, Shatin, NT, SAR.
Pak Ho
PH
Leung
Li
L
Zhang
Zhong
Z
Zuo
Ge
G
Lin
D000470:Alkaloids / Q000008:administration & dosage / Q000493:pharmacokinetics; D001692:Biological Transport; D018938:Caco-2 Cells / Q000378:metabolism; D002463:Cell Membrane Permeability; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007408:Intestinal Absorption; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000493:pharmacokinetics*; D041901:Stemonaceae
D000470:Alkaloids; D010936:Plant Extracts