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This Article Full Text (Publish Ahead of Print[PDF]) All Versions of this Article: 89/1/177    most recent ajcn.2008.26559v1 Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Reboul, E. Articles by Borel, P. Search for Related Content PubMed PubMed Citation Articles by Reboul, E. Articles by Borel, P. Agricola Articles by Reboul, E. Articles by Borel, P.

ATP-binding cassette transporter A1 is significantly involved in the intestinal absorption of - and -tocopherol but not in that of retinyl palmitate in mice^1,2,3

¹ From INRA, UMR1260 "Nutriments Lipidiques et Prévention des Maladies Métaboliques", INSERM, U476, Université Aix-Marseille 1, Université Aix-Marseille 2, Faculté de Médecine, IPHM-IFR 125, Marseille, France (ER, MM, J-FL, and PB); the Centre d'Immunologie de Marseille Luminy, INSERM/CNRS, Université Aix-Marseille, Parc Scientifique de Luminy, Marseille, France (DT and GC); and INSERM, U866, IFR Santé-STIC, Faculté de Médecine, Université de Bourgogne, Dijon, France (AK).

² The work at the Centre d'Immunologie de Marseille Luminy was supported by institutional grants from INSERM and CNRS and specific grants (FLIPPASE/MPCM) from the European Community. DT was supported in part by a fellowship allocated by the Nouvelle Société Française d'Athérosclérose/Pfizer.

³ Reprints not available. Address correspondence to P Borel, UMR 476/1260 INRA, Faculté de Medécine, 27 Boulevard Jean-Moulin, 13385 Marseille, Cedex 5, France. E-mail: patrick.borel{at}univmed.fr.

ABSTRACT

Background: It has long been assumed that newly absorbed vitamin A and E enter the body only via enterocyte-produced chylomicrons. However, recent results in cell cultures have shown that a fraction of -tocopherol is secreted with intestinal HDL.

Objective: The aims of this study were to identify this transporter and to assess whether it is significantly implicated in the in vivo intestinal absorption of the 2 main dietary forms of vitamin E (ie, - and -tocopherol) and in that of retinyl palmitate (vitamin A).

Design: Having performed preliminary experiments in the Caco-2 cell model, we compared fasting and postprandial plasma concentrations of vitamins A and E in mice deficient in ATP-binding cassette A1 (ABCA1) transporter and in wild-type mice.

Results: A substantial efflux of - and -tocopherol, but not of retinyl esters, was induced by the presence of apolipoprotein A-I at the basolateral side of Caco-2 monolayers. The efflux of - and -tocopherol was also impaired by glyburide and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid. The postprandial response of plasma -tocopherol was 4-fold lower in ABCA1^–/– mice (P = 0.025) than in wild-type mice, whereas no significant difference was observed for retinyl esters. Fasting plasma -tocopherol, but not vitamin A, concentrations were lower in mice bearing the genetic deletion.

Conclusions: ABCA1 is the transporter responsible for the in vivo secretion of - and -tocopherol with intestinal HDL, and this pathway is significantly implicated in the intestinal absorption and plasma status of vitamin E but not of vitamin A.

Received for publication June 18, 2008. Accepted for publication September 28, 2008.