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Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers
Published on: October 17, 2013
Effect of ketocholate derivatives on methotrexate uptake in Caco-2 cell monolayers
Gong Chen1, Lin Yang, Hu Zhang
1School of Pharmacy, University of Otago, PO Box 56, Dunedin, New Zealand. gongchenmel@gmail.com
International Journal of Pharmaceutics
|May 12, 2012
Summary
Ketocholates, unlike cholate, reduce methotrexate (MTX) uptake by Caco-2 cells by increasing membrane fluidity. This suggests ketocholates indirectly inhibit MTX influx transporters by altering their lipid environment.
Area of Science:
- Pharmacology
- Cell Biology
- Biochemistry
Background:
- Bile salts (BS) like cholate (C) can inhibit methotrexate (MTX) permeation across Caco-2 cell monolayers.
- Understanding the mechanism of this inhibition is crucial for drug delivery and efficacy.
Purpose of the Study:
- To investigate the mechanism by which different bile salts affect MTX uptake in Caco-2 cells.
- To compare the effects of cholate (C), 7-ketocholate (7-MKC), 12-ketocholate (12-MKC), 3,7-diketocholate (DKC), and triketocholate (TKC) on MTX uptake.
Main Methods:
- Determined critical micelle concentrations (CMCs) and cytotoxicities of various bile salts.
- Assessed the effects of bile salts on Caco-2 cell membrane fluidity.
- Quantified MTX uptake using liquid chromatography-tandem mass spectrometry (LC-MS/MS).
Main Results:
- Ketocholates exhibited lower cytotoxicity and higher CMCs compared to cholate.
- 7-MKC and 12-MKC showed a reduced ability to inhibit MTX uptake compared to cholate.
- Ketocholates increased membrane fluidity in different regions (hydrophilic or hydrophobic) of Caco-2 cell membranes, while cholate had minimal effect.
Conclusions:
- Modifying bile salts by introducing keto groups alters their physicochemical properties and biological impact.
- Ketocholates inhibit MTX uptake, correlating with increased membrane fluidity, suggesting indirect inhibition of influx transporters via lipid environment disruption.
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