Fatty acids affect micellar properties and modulate vitamin D uptake and basolateral efflux in Caco-2 cells

• Published in: The Journal of nutritional biochemistry Vol. 24; no. 10; pp. 1751 - 1757
• Main Authors: Goncalves, Aurélie, Gleize, Béatrice, Roi, Stéphanie, Nowicki, Marion, Dhaussy, Amélie, Huertas, Alain, Amiot, Marie-Josèphe, Reboul, Emmanuelle
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-10-2013; Elsevier
• Subjects: Bioavailability; Caco-2 Cells; Caco-2 TC-7 cells; Cholecalciferol; Cholecalciferol - metabolism; Fatty acids; Fatty Acids, Unsaturated - pharmacology; Food and Nutrition; Humans; Intestinal absorption; Intestinal Absorption - drug effects; Intestinal Absorption - physiology; Life Sciences; Membrane Proteins - metabolism; Micelles; Mixed micelles; Oleic Acid - pharmacology; Scavenger Receptors, Class B - metabolism; ABCA1; PBS; Mixed micelles; Caco-2 TC-7 cells; SR-BI; FED; PUFA; Cholecalciferol; MUFA; Bioavailability; Fatty acids; ARA; DMEM; PA; OA; NPC1L1; LA; FBS; ALA; EPA; CD36; FA; DHA; Intestinal absorption; scavenger receptor class B type I; oleic acid; fatty acid; phosphate-buffered saline; cluster determinant 36; fish oil enriched in DHA; palmitic acid; monounsaturated FA; ATP binding cassette A1; Niemann-pick C1-like 1; docosahexaenoic acid; polyunsaturated FA; arachidonic acid; linoleic acid; Dulbecco's modified Eagle's medium; fetal bovine serum; eicosapentaenoic acid; α-linolenic acid; DIETARY-FAT; E TRANSPORT; ENTEROCYTES; I SR-BI; RISK; CAROTENOIDS; INTESTINAL-ABSORPTION; REPLACEMENT; CARDIOVASCULAR-DISEASE; GENE-EXPRESSION
• ISSN: 0955-2863; 1873-4847
• DOI: 10.1016/j.jnutbio.2013.03.004

We have recently shown that vitamin D3 (cholecalciferol) absorption is not a simple passive diffusion but involves cholesterol transporters. As free fatty acids (FAs) modulate cholesterol intestinal absorption and metabolism, we hypothesized that FAs may also interact with vitamin D absorption. Effects of FAs were evaluated at different levels of cholecalciferol intestinal absorption. First, the physicochemical properties of micelles formed with different FAs were analyzed. The micelles were then administered to human Caco-2 cells in culture to evaluate FA effects on (i) cholecalciferol uptake and basolateral efflux and (ii) the regulation of genes coding proteins involved in lipid absorption process. Micellar electric charge was correlated with both FA chain length and degree of unsaturation. Long-chain FAs at 500 μM in mixed micelles decreased cholecalciferol uptake in Caco-2 cells. This decrease was annihilated as soon as the long-chain FAs were mixed with other FAs. Oleic acid significantly improved cholecalciferol basolateral efflux compared to other FAs. These results were partly explained by a modulation of genes coding for lipid transport proteins such as Niemann-pick C1-like 1 and scavenger receptor class B type I. The data reported here show for the first time that FAs can interact with cholecalciferol intestinal absorption at different key steps of the absorption process. Cholecalciferol intestinal absorption may thus be optimized according to oil FA composition.