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.
MeSH terms
-
Bucladesine / pharmacology
-
CREB-Binding Protein
-
Cell Differentiation
-
Colforsin / pharmacology
-
Cyclic AMP / metabolism
-
Cyclic AMP-Dependent Protein Kinases / metabolism
-
Cytokines / metabolism
-
Dinoprostone / pharmacology
-
Enzyme Inhibitors / pharmacology
-
Gene Expression Regulation / drug effects*
-
Histamine / pharmacology*
-
Humans
-
Isoquinolines / pharmacology
-
Macrophages / cytology
-
Macrophages / drug effects
-
Macrophages / metabolism*
-
Monocytes / cytology
-
Monocytes / drug effects
-
Monocytes / metabolism*
-
Nuclear Proteins / metabolism
-
Promoter Regions, Genetic / drug effects
-
Prostaglandin D2 / pharmacology
-
RNA, Messenger / genetics
-
RNA, Messenger / metabolism
-
Receptors, Histamine H1 / genetics
-
Receptors, Histamine H1 / metabolism
-
Receptors, Histamine H2 / genetics
-
Receptors, Histamine H2 / metabolism*
-
Receptors, LDL / biosynthesis
-
Receptors, LDL / genetics*
-
Receptors, Oxidized LDL
-
Scavenger Receptors, Class E
-
Signal Transduction
-
Sulfonamides*
-
Tetradecanoylphorbol Acetate / pharmacology
-
Trans-Activators / metabolism
-
Tumor Cells, Cultured
-
Up-Regulation
Substances
-
Cytokines
-
Enzyme Inhibitors
-
Isoquinolines
-
Nuclear Proteins
-
OLR1 protein, human
-
RNA, Messenger
-
Receptors, Histamine H1
-
Receptors, Histamine H2
-
Receptors, LDL
-
Receptors, Oxidized LDL
-
Scavenger Receptors, Class E
-
Sulfonamides
-
Trans-Activators
-
Colforsin
-
Bucladesine
-
Histamine
-
Cyclic AMP
-
CREB-Binding Protein
-
CREBBP protein, human
-
Cyclic AMP-Dependent Protein Kinases
-
Dinoprostone
-
N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide
-
Tetradecanoylphorbol Acetate
-
Prostaglandin D2