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The Mesenteric Lymph Duct Cannulated Rat Model: Application to the Assessment of Intestinal Lymphatic Drug Transport
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The Mesenteric Lymph Duct Cannulated Rat Model: Application to the Assessment of Intestinal Lymphatic Drug Transport

Published on: March 6, 2015

Characterization of lipophilic drug binding to rat intestinal fatty acid binding protein

Tony Velkov1, Maria L R Lim, James Horne

  • 1Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, 3052, Victoria, Australia.

Molecular and Cellular Biochemistry
|January 23, 2009
PubMed

Intestinal fatty acid binding protein (I-FABP) is present at high levels in the absorptive cells of the intestine (enterocytes) where it plays a role in the intracellular solubilization of fatty acids (FA). However, I-FABP has also been shown to bind to a range of non-FA ligands, including some lipophilic drug molecules, albeit with generally lower affinity than FA. The significance of these lower affinity interactions with exogenous compounds is not known. In this manuscript, we describe further characterization of drug-rat I-FABP binding interactions using a thermal-shift assay. A structural explanation of the observed affinity of rat I-FABP for different drugs based on spectroscopic data and modeling experiments is presented. In addition, immunocytochemistry has been used to probe the expression of I-FABP in a cell culture model reflective of the absorptive cells of the small intestine. Taken together, these data suggest a possible role for I-FABP in the disposition of some lipophilic drugs within the enterocyte.

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