title: Suppression of mast cell degranulation by a novel ceramide kinase inhibitor, the F-12509A olefin isomer K1.
abstract: Antigen-induced degranulation of mast cells plays a pivotal role in allergic and inflammatory responses. Recently, ceramide kinase (CERK) and its phosphorylated product ceramide 1-phosphate (C1P) have emerged as important players in mast cell degranulation. Here, we describe the synthesis of a novel F-12509A olefin isomer, K1, as an effective CERK inhibitor. In vitro kinase assays demonstrated that K1 effectively inhibits CERK without inhibiting sphingosine kinase and diacylglycerol kinase. Treating RBL-2H3 cells with K1 reduced cellular C1P levels to 40% yet had no effect on cell growth. Furthermore, treatment with K1 significantly suppressed both calcium ionophore- and IgE/antigen-induced degranulation, indicating that K1 interferes with signals that happen downstream of Ca(2+) mobilization. Finally, we show that K1 affects neither IgE/antigen-induced global tyrosine phosphorylation nor subsequent Ca(2+) elevation, suggesting a specificity for CERK-mediated signals. Our novel CERK inhibitor provides a useful tool for studying the biological functions of CERK and C1P. Moreover, to our knowledge, this is the first report demonstrating that inhibition of CERK suppresses IgE/antigen-induced mast cell degranulation. This finding suggests that CERK inhibitors might be a potential therapeutic tool in the treatment of allergic diseases.
authors.affiliation: Department of Biomembrane and Biofunctional Chemistry, Graduate School of Pharmaceutical Science, Hokkaido University, Kita 12, Nishi 6, Kita-ku, Sapporo 060-0812, Japan.
authors.forename: Jin-Wook
authors.initials: JW
authors.lastname: Kim
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Inagaki
authors.forename: Susumu
authors.initials: S
authors.lastname: Mitsutake
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Maezawa
authors.forename: Shigeo
authors.initials: S
authors.lastname: Katsumura
authors.forename: Yeon-Woo
authors.initials: YW
authors.lastname: Ryu
authors.forename: Chang-Seo
authors.initials: CS
authors.lastname: Park
authors.forename: Masaru
authors.initials: M
authors.lastname: Taniguchi
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Igarashi
mesh_terms: D000475:Alkenes / Q000737:chemistry; D016227:Benzoquinones / Q000737:chemistry / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D015550:Cell Degranulation / Q000187:drug effects; D002463:Cell Membrane Permeability; D002478:Cells, Cultured; D002625:Chemistry, Organic / Q000379:methods; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000494:pharmacology*; D006801:Humans; D007073:Immunoglobulin E / Q000494:pharmacology; D007536:Isomerism; D008407:Mast Cells / Q000187:drug effects* / Q000502:physiology; D010766:Phosphorylation / Q000187:drug effects; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018675:Toxicity Tests; D014443:Tyrosine / Q000378:metabolism
chemical_list: D000475:Alkenes; D016227:Benzoquinones; D004791:Enzyme Inhibitors; C411675:F 12509A; D007073:Immunoglobulin E; D014443:Tyrosine; D017853:Phosphotransferases (Alcohol Group Acceptor); C066324:ceramide kinase; D002118:Calcium