title: C2-ceramide inhibits LPS-induced nitric oxide production in RAW 264.7 macrophage cells through down-regulating the activation of Akt.
abstract: The effect of C(2)-ceramide, a membrane-permeable ceramide analogue, on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells was studied. The non-toxic concentration of C(2)-ceramide inhibited LPS-induced NO production. It was due to the attenuated expression of the inducible type of NO synthase (iNOS). C(2)-ceramide did not influence the phosphorylation of a series of mitogen-activated protein (MAP) kinases in response to LPS. On the other hand, C(2)-ceramide down-regulated the phosphorylation of Akt in LPS-stimulated RAW 264.7 cells, followed by the impairment of nuclear factor (NF)-kappaB activation. Moreover, the Akt dominant-negative mutant inhibited LPS-induced NO production. C(2)-ceramide was suggested to inhibit LPS-induced NO production through down-regulating the activation of Akt.
authors.affiliation: Department of Microbiology and Immunology and Division of Bacterial Toxin, Research Center for Infectious Disease, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Koide
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Isamu
authors.initials: I
authors.lastname: Mori
authors.forename: Mya Mya
authors.initials: MM
authors.lastname: Mu
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Yoshida
authors.forename: Takashi
authors.initials: T
authors.lastname: Yokochi
mesh_terms: D000818:Animals; D002460:Cell Line; D015536:Down-Regulation; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004926:Escherichia coli / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D016328:NF-kappa B / Q000096:biosynthesis; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D052247:Nitric Oxide Synthase Type II; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D051057:Proto-Oncogene Proteins c-akt; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D014162:Transfection
chemical_list: D004791:Enzyme Inhibitors; D008070:Lipopolysaccharides; C064769:N-acetylsphingosine; D016328:NF-kappa B; D011518:Proto-Oncogene Proteins; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases; D013110:Sphingosine