title: Flavones suppress the expression of the high-affinity IgE receptor FcepsilonRI in human basophilic KU812 cells.
abstract: We examined the effect of flavones on the expression of the high-affinity IgE receptor FcepsilonRI, which plays a central role in the IgE-mediated allergic response. Flow cytometric analysis showed that the flavones chrysin and apigenin were able to reduce the cell surface expression of FcepsilonRI in human basophilic KU812 cells. Immunoblot analysis revealed that the total cellular expression of the FcepsilonRI alpha and gamma chains decreased upon treatment with chrysin and apigenin. Moreover, the level of mRNA expression of the FcepsilonRI alpha and gamma chains also decreased when the cells were cultured with the two flavones. Previously, we demonstrated that the reduction of extracellular signal-regulated kinase1/2 (ERK1/2) phosphorylation was involved in the downregulation of FcepsilonRI expression. The two flavones were shown to reduce the level of ERK1/2 phosphorylation. These results suggested that chrysin and apigenin have the ability to downregulate FcepsilonRI expression and this suppressive effect may be due to the reduction of ERK1/2 phosphorylation.
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Satomi
authors.initials: S
authors.lastname: Yano
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tachibana
authors.forename: Koji
authors.initials: K
authors.lastname: Yamada
mesh_terms: D047310:Apigenin / Q000494:pharmacology; D001491:Basophils / Q000378:metabolism*; D047309:Flavones / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D007700:Kinetics; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D010766:Phosphorylation; D012333:RNA, Messenger / Q000032:analysis; D017455:Receptors, IgE / Q000235:genetics*; D014407:Tumor Cells, Cultured
chemical_list: D047309:Flavones; D005419:Flavonoids; D012333:RNA, Messenger; D017455:Receptors, IgE; C043561:chrysin; D047310:Apigenin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3