AJP - Gastrointestinal and Liver Physiology, Vol 273, Issue 2 289-G295, Copyright © 1997 by American Physiological Society
Fatty acid regulation of fatty acid-binding protein expression in the small intestine
H. Poirier, I. Niot, P. Degrace, M. C. Monnot, A. Bernard and P. Besnard
Laboratoire de Physiologie de la Nutrition, Ecole Nationale Superieure de Biologie Appliquee a la Nutrition et a l'Alimentation, Universite de Bourgogne, Dijon, France.
The effects of dietary oil intake and fatty acid infusions on the
expression of intestinal and liver fatty acid-binding proteins (I-FABP and
L-FABP, respectively) were investigated in the small intestine of mice. A
daily force-feeding for 7 days with 0.2 ml sunflower oil specifically
increased L-FABP mRNA and protein levels in duodenum and proximal jejunum.
This upregulation was mediated in time- and dose-dependent manners by a
minute quantity of linoleic acid, the main fatty acid found in sunflower
oil. The L-FABP induction was only found with long-chain fatty acids, with
the nonmetabolizable, substituted fatty acid alpha-bromopalmitate being far
more active. A hormonally mediated effect is unlikely because long-chain
fatty acids induced L-FABP mRNA in the Caco-2 cell line cultured in
serum-free medium. Therefore, long-chain fatty acids are strong inducers of
L-FABP gene expression in the small intestine. In contrast to data found in
the rat, I-FABP gene expression appears to be unaffected by a
lipid-enriched diet in the mouse.
