title: Histamine increases the expression of LOX-1 via H2 receptor in human monocytic THP-1 cells.
abstract: Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a member of the scavenger receptor family, and is known to be expressed in monocytes/macrophages. We investigated the effect of histamine on the expression of LOX-1 in cells of the human monocytic leukemia cell line THP-1. Histamine as well as forskolin and dibutyryl cyclic AMP (Bt2-cAMP) stimulated the THP-1 monocytes to express the LOX-1 gene at the transcription level. This histamine effect on LOX-1 gene expression, via the histamine H2 receptor-mediated cAMP signal transduction pathway, was reduced after differentiation of the cells into macrophages, even though forskolin and Bt2-cAMP still enhanced the gene expression. The alteration of the responsiveness of LOX-1 expression to histamine was related to suppressed expression of the H2 receptor in THP-1 macrophages. The switch of the predominant class of histamine receptors between H1 and H2 would modulate the effects of histamine on LOX-1 gene expression in monocytes and macrophages, and therefore, would play a certain role in the inflammatory aspects of atherogenesis.
authors.affiliation: Department of Pathology and Cell Biology, School of Medicine, University of Occupational Environmental Health, Kitakyushu, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Tanimoto
authors.forename: Y
authors.initials: Y
authors.lastname: Murata
authors.forename: M
authors.initials: M
authors.lastname: Nomaguchi
authors.forename: S
authors.initials: S
authors.lastname: Kimura
authors.forename: N
authors.initials: N
authors.lastname: Arima
authors.forename: H
authors.initials: H
authors.lastname: Xu
authors.forename: T
authors.initials: T
authors.lastname: Hamada
authors.forename: Y
authors.initials: Y
authors.lastname: Sasaguri
mesh_terms: D003994:Bucladesine / Q000494:pharmacology; D050882:CREB-Binding Protein; D002454:Cell Differentiation; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D015232:Dinoprostone / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects*; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D007546:Isoquinolines / Q000494:pharmacology; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009000:Monocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000187:drug effects; D015230:Prostaglandin D2 / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011969:Receptors, Histamine H1 / Q000235:genetics / Q000378:metabolism; D011970:Receptors, Histamine H2 / Q000235:genetics / Q000378:metabolism*; D011973:Receptors, LDL / Q000096:biosynthesis / Q000235:genetics*; D051131:Receptors, Oxidized LDL; D051127:Scavenger Receptors, Class E; D015398:Signal Transduction; D013449:Sulfonamides; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D015534:Trans-Activators / Q000378:metabolism; D014407:Tumor Cells, Cultured; D015854:Up-Regulation
chemical_list: D016207:Cytokines; D004791:Enzyme Inhibitors; D007546:Isoquinolines; D009687:Nuclear Proteins; C495137:OLR1 protein, human; D012333:RNA, Messenger; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D011973:Receptors, LDL; D051131:Receptors, Oxidized LDL; D051127:Scavenger Receptors, Class E; D013449:Sulfonamides; D015534:Trans-Activators; D005576:Colforsin; D003994:Bucladesine; D006632:Histamine; D000242:Cyclic AMP; D050882:CREB-Binding Protein; C494363:CREBBP protein, human; D017868:Cyclic AMP-Dependent Protein Kinases; D015232:Dinoprostone; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide; D013755:Tetradecanoylphorbol Acetate; D015230:Prostaglandin D2