Journal
CHEMICO-BIOLOGICAL INTERACTIONS
Volume 181, Issue 2, Pages 272-278Publisher
ELSEVIER IRELAND LTD
DOI: 10.1016/j.cbi.2009.06.016
Keywords
Docosahexaenoic acid; Oleic acid; Aluminium; Paracellular absorption; Caco-2; Tight junctions
Ask authors/readers for more resources
Passive paracellular absorption, regulated by tight junctions (TJs), is the main route for absorption of poorly absorbed hydrophilic substances. Surface active substances, such as fatty acids, may enhance absorption of these substances by affecting the integrity of TJ and increasing the permeability. It has been suggested that aluminium (Al) absorption occurs mainly by the paracellular route. Herein, we investigated if physiologically relevant exposures of fully differentiated Caco-2 cell monolayers to oleic acid and docosahexaenoic acid (DHA), which are fatty acids common in food, increase absorption of Al and the paracellular marker mannitol. In an Al toxicity test, mannitol and Al absorption through Caco-2 cell monolayers were similarly modulated by Al concentrations between I and 30 mM, suggesting that absorption of the two compounds occurred via the same pathways. Exposure of Caco-2 cell monolayers to non-toxic concentrations of Al (2 mM) and C-14-mannitol in fatty acid emulsions (15 and 30 mM oleic acid, 5 and 10 mM DHA) caused a decreased transepithelial electrical resistance (TEER). Concomitantly. fractional absorption of Al and mannitol, expressed as percentage of apical Al and mannitol retrieved at the basolateral side, increased with increasing dose of fatty acids. Transmission electron microscopy was applied to assess the effect of oleic acid on the morphology of TJ. It was shown that oleic acid caused a less structured morphology of TJ in Caco-2 cell monolayers. Taken together our findings indicate that fatty acids common in food increase the paracellular intestinal absorption of Al. These findings may influence future risk assessment of human Al exposure. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available