Atherosclerosis 181 (2005) 75–85 Basic Research Changes in intestinal and liver global gene expression in response to a phytosterol-enriched diet Laura Calpe-Berdiel a, 1 , Joan Carles Escol` a-Gil a, ∗, 1 , Vicent Ribas a , Aleix Navarro-Sastre b , Josep Garc´ es-Garc´ es c , Francisco Blanco-Vaca a, ∗ a Servei de Bioqu´ ımica, Institut de Recerca de l’Hospital de la Santa Creu i Sant Pau, C/ Antoni M. Claret 167, 08025 Barcelona, Spain b Institut de Bioqu´ ımica Cl´ ınica, Corporaci´ o Sanit` aria Cl´ ınic, Barcelona, Spain c Lipofoods S.L., Gav` a, Barcelona, Spain Received 22 June 2004; received in revised form 27 October 2004; accepted 5 November 2004 Available online 12 February 2005 Abstract Background: Dietary phytosterols are a recommended therapeutic option for decreasing plasma cholesterol. The increased activity of ATP- binding cassette (ABC) transporters ABCA1, ABCG5 and ABCG8, or, alternatively, a decrease in Niemann–Pick C1 Like 1 (NPC1L1) could mediate the reduction in intestinal cholesterol absorption caused by phytosterols. Other biological properties such as a direct immune modulatory activity have recently been ascribed to these plant compounds. Methods: To gain insight into the molecular effects of phytosterols, global genome-wide gene profiling and real-time RT-PCR studies were conducted in small intestines and livers of phytosterol-treated apolipoprotein E-deficient (apoE -/- ) mice. Re-testing of the main results was performed in C57BL/6J and LDL receptor-deficient (LDLR -/- ) mice. Results: Intestinal cholesterol absorption was decreased in all mouse models but plasma cholesterol was only decreased in apoE -/- and LDLR -/- mice. ABCA1, ABCG5, ABCG8 and NPC1L1 mRNA levels were slightly reduced in the intestine of phytosterol-treated apoE -/- and LDLR -/- mice, but increased in C57BL/6J-treated mice. Phytosterols changed genes involved in immune regulation in apoE -/- mice. However, these changes were less extensive in LDLR -/- mice and were not found in C57BL/6J mice. Conclusions: Inhibition of intestinal cholesterol absorption by phytosterols is not mediated via transcriptional changes in ABCA1, ABCG5, ABCG8 or NPC1L1. Changes suggestive of immunomodulation are associated with the hypocholesterolemic effect of phytosterols and with apoE deficiency. © 2005 Elsevier Ireland Ltd. All rights reserved. Keywords: Phytosterols; Cholesterol; ATP-binding cassette transporter; Atherosclerosis; Immune system; Cancer Abbreviations: ABCA1, ATP-binding cassette transporter A1; ABCG5, ATP-binding cassette transporter G5; ABCG8, ATP-binding cassette transporter G8; ALT, alanine aminotransferase; apoE, apolipoprotein E; apoE -/- , apoE-deficient mice; ETV6, ETS variant gene 6; FDPS, farnesyl diphosphate synthase; FoxQ1, forkhead box Q1; FPLC, fast protein liquid chromatography; GC–MS, gas–liquid chromatography–mass spectrometry; HDL, high-density lipoprotein; IDL, intermediate-density lipoprotein; IgK-V, immunoglobulin kappa chain variable; LDL, low-density lipoprotein; LDLR -/- , LDL receptor-deficient mice; LFC, limit fold change; LXR, liver X receptor; MARCO, macrophage receptor with collagenous structure; NCEP, National Cholesterol Education Program; NPC1L1, Niemann–Pick C1 Like 1; Reg, regenerating islet-derived; RT-PCR, reverse-transcriptase polymerase chain reaction; SREBP, sterol regulatory element binding protein; SAA3, serum amyloid A3; VLDL, very-low-density lipoprotein ∗ Corresponding authors. Tel.: +34 93 2919451; fax: +34 93 2919196. E-mailaddresses: jescola@hsp.santpau.es (J.C. Escol` a-Gil), fblancova@hsp.santpau.es (F. Blanco-Vaca). 1 These authors contributed equally to this work. 0021-9150/$ – see front matter © 2005 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.atherosclerosis.2004.11.025