title: A possible mechanism for atherosclerosis induced by polycyclic aromatic hydrocarbons.
abstract: Polycyclic aromatic hydrocarbons (PAHs), aryl hydrocarbon receptor (AHR) ligands, induce atherogenesis. Liver X receptor (LXR) alpha is known to be involved in the control of cholesterol homeostasis. Thus, the purpose of this study was to investigate the effects of 3-methlycholanthrene (MC), one of the PAHs, on LXRalpha-mediated signal transductions. We found that expression of mRNAs for ATP binding cassette A1, sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthase, and stearoyl-CoA desaturase was suppressed by treatment of HepG2 cells with MC. A luciferase reporter assay revealed that LXRalpha- and SREBP-1c-mediated transactivations were inhibited by MC via AHR. Based on these lines of evidence, we propose that down-regulation of the LXRalpha-regulated genes by PAHs is one of the causes responsible for atherosclerosis induced by PAHs.
authors.affiliation: Laboratory of Drug Metabolism, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Iwano
authors.forename: Manabu
authors.initials: M
authors.lastname: Nukaya
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Saito
authors.forename: Fumie
authors.initials: F
authors.lastname: Asanuma
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kamataki
mesh_terms: D001161:Arteriosclerosis / Q000139:chemically induced* / Q000235:genetics / Q000378:metabolism; D001551:Benz(a)Anthracenes / Q000494:pharmacology / Q000633:toxicity; D022762:CCAAT-Enhancer-Binding Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D000071518:Liver X Receptors; D008954:Models, Biological; D057093:Orphan Nuclear Receptors; D011084:Polycyclic Aromatic Hydrocarbons / Q000494:pharmacology* / Q000633:toxicity; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects / Q000235:genetics
chemical_list: C504364:3-methlycholanthrene; D001551:Benz(a)Anthracenes; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D000071518:Liver X Receptors; C000605213:NR1H3 protein, human; D057093:Orphan Nuclear Receptors; D011084:Polycyclic Aromatic Hydrocarbons; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D018336:Receptors, Aryl Hydrocarbon; D018160:Receptors, Cytoplasmic and Nuclear; C497387:SREBF1 protein, human; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors