title: ABCG1 is involved in vitamin E efflux.
abstract: Vitamin E membrane transport has been shown to involve the cholesterol transporters SR-BI, ABCA1 and NPC1L1. Our aim was to investigate the possible participation of another cholesterol transporter in cellular vitamin E efflux: ABCG1. In Abcgl-deficient mice, vitamin E concentration was reduced in plasma lipoproteins whereas most tissues displayed a higher vitamin E content compared to wild-type mice. α- and γ-tocopherol efflux was increased in CHO cells overexpressing human ABCG1 compared to control cells. Conversely, α- and γ- tocopherol efflux was decreased in ABCG1-knockdown human cells (Hep3B hepatocytes and THP-1 macro- phages). Interestingly, α- and γ-tocopherol significantly downregulated ABCG1 and ABCA1 expression levels in Hep3B and THP-1, an effect confirmed in vivo in rats given vitamin E for 5 days. This was likely due to reduced LXR activation by oxysterols, as Hep3B cells and rat liver treated with vitamin E displayed a significantly reduced content in oxysterols compared to their respective controls. Overall, the present study reveals for the first time that ABCG1 is involved in cellular vitamin E efflux.
authors.forename: Maryline
authors.initials: M
authors.lastname: Olivier
authors.forename: Remain
authors.initials: R
authors.lastname: BottG
authors.forename: Eric
authors.initials: E
authors.lastname: Frisdal
authors.forename: Marion
authors.initials: M
authors.lastname: Nowick
authors.forename: Wanee
authors.initials: W
authors.lastname: Plengpanich
authors.forename: Charles
authors.initials: C
authors.lastname: Desmarchelier
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Roi
authors.forename: Carmel M
authors.initials: CM
authors.lastname: Quinn
authors.forename: Ingrid
authors.initials: I
authors.lastname: Gelissen
authors.forename: Wendy
authors.initials: W
authors.lastname: Jessup
authors.forename: Miranda
authors.initials: M
authors.lastname: Van Eck
authors.forename: Maryse
authors.initials: M
authors.lastname: Guérin
authors.forename: Wilfried
authors.initials: W
authors.lastname: Le Goff
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Reboul
mesh_terms: D064286:ATP Binding Cassette Transporter 1 / Q000235:genetics / Q000378:metabolism; D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1; D018528:ATP-Binding Cassette Transporters / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D016466:CHO Cells; D002839:Chromans / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D015536:Down-Regulation; D006801:Humans; D008074:Lipoproteins / Q000172:deficiency / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D000071518:Liver X Receptors; D008264:Macrophages / Q000378:metabolism; D008810:Mice, Inbred C57BL; D009928:Organ Specificity; D057093:Orphan Nuclear Receptors / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D051381:Rats; D014162:Transfection; D014810:Vitamin E / Q000378:metabolism*
chemical_list: D064286:ATP Binding Cassette Transporter 1; D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1; D018528:ATP-Binding Cassette Transporters; D002839:Chromans; D008074:Lipoproteins; D000071518:Liver X Receptors; D057093:Orphan Nuclear Receptors; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014810:Vitamin E; C577833:Abca1 protein, mouse; C419353:ABCG1 protein, human; C487540:ABCG1 protein, mouse; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid