Lycopene absorption in human intestinal cells and in mice involves scavenger receptor class B type I but not Niemann-Pick C1-like 1.
Cholesterol membrane transporters scavenger receptor class B type I (SR-BI) and (cluster determinant 36) are involved in intestinal uptake of lutein and beta-carotene, 2 of the 3 main carotenoids of the human diet. The aim of this work was therefore to determine whether SR-BI and NPC1L1 (Niemann-Pick C1-like 1), another cholesterol transporter, are implicated in absorption of lycopene, the 3rd main carotenoid of the human diet. Anti-human SR-BI antibody and block lipid transport 1 (BLT1) (a chemical inhibitor of lipid transport by SR-BI) impaired up to 60% (all-E) and (5Z)-lycopene uptake (P < 0.05) by Caco-2 cell monolayers, which were used as a model of human intestinal epithelium. The involvement of SR-BI in lycopene absorption in vivo was then verified by comparing plasma lycopene concentrations in wild-type and SR-BI transgenic mice that were fed a diet enriched with 0.25 g/kg (all-E)-lycopene for 1 mo. Plasma lycopene concentrations were approximately 10-fold higher (P < 0.001) in mice overexpressing SR-BI in the intestine than in wild-type mice, confirming the involvement of SR-BI in lycopene absorption. Further experiments showed that (all-E)-lycopene did not affect SR-BI mRNA levels in Caco-2 cells or mouse intestine. In contrast to SR-BI, neither anti-human NPC1L1 antibody nor ezetimibe, used as inhibitors of lycopene uptake via NPC1L1, significantly impaired (all-E) or (5Z)-lycopene uptake by Caco-2 monolayers. Thus, the present data show that lycopene absorption is, at least in part, mediated by SR-BI but not by NPC1L1.
Moussa
Myriam
M
Institut National de la Recherche Agronomique, UMR1260 Nutriments Lipidiques et Prévention des Maladies Métaboliques, F-13385 Marseille, France.
Landrier
Jean-François
JF
Reboul
Emmanuelle
E
Ghiringhelli
Odette
O
Coméra
Christine
C
Collet
Xavier
X
Fröhlich
Kati
K
Böhm
Volker
V
Borel
Patrick
P
D000818:Animals; D000924:Anticholesteremic Agents / Q000494:pharmacology; D001384:Azetidines / Q000494:pharmacology; D001682:Biological Availability; D018938:Caco-2 Cells; D002338:Carotenoids / Q000378:metabolism / Q000493:pharmacokinetics* / Q000494:pharmacology; D004032:Diet; D000069438:Ezetimibe; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007408:Intestinal Absorption / Q000502:physiology; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000166:cytology* / Q000187:drug effects; D000077276:Lycopene; D008297:Male; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins; D051379:Mice; D008822:Mice, Transgenic; D009747:Nutritional Physiological Phenomena; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051122:Scavenger Receptors, Class B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*
D000924:Anticholesteremic Agents; D001384:Azetidines; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C410800:NPC1L1 protein, human; D012333:RNA, Messenger; C495124:SCARB1 protein, human; C454739:Scarb1 protein, mouse; D051122:Scavenger Receptors, Class B; D002338:Carotenoids; D000069438:Ezetimibe; D000077276:Lycopene