シミズ タツヤ   Shimizu Tatsuya
  清水 達也
   所属   医学研究科 医学研究科 (医学部医学科をご参照ください)
   職種   教授
論文種別 原著
言語種別 英語
査読の有無 査読なし
表題 Transcriptional regulation of inducible nitric oxide synthase in cultured neonatal rat cardiac myocytes.
掲載誌名 正式名:Circulation research
略  称:Circ Res
ISSNコード:(0009-7330)0009-7330(Linking)
掲載区分国外
巻・号・頁 81(6),pp.911-21
著者・共著者 Kinugawa K†, Shimizu T, Yao A, Kohmoto O, Serizawa T, Takahashi T
発行年月 1997/12
概要 Previous work has demonstrated that inducible NO synthase (iNOS) can be expressed in cardiac myocytes. In this study, we investigated transcriptional regulation of the iNOS gene in these cells. Lipopolysaccharide (LPS) induced iNOS mRNA and protein in cultured neonatal rat cardiac myocytes. H-89, dexamethasone, herbimycin, genistein, staurosporine, or pyrrolidine dithiocarbamate (PDTC) attenuated the iNOS induction by LPS. Forskolin, interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, or interferon (IFN)-gamma enhanced the LPS-induced iNOS expression. Combined stimulation of IL-6 and TNF-alpha also induced iNOS. The 5'-upstream sequence of the rat iNOS gene contains the nuclear factor-kappa B (NF-kappa B) site, CAAT box, IFN-gamma activation site (GAS), and IFN regulatory factor (IRF) site. DNase I footprinting assay revealed that the nuclear factors binding to these elements were increased by LPS exposure. Transient transfection assay suggested that these elements were indispensable for transcriptional regulation of the iNOS induction. Electrophoretic mobility shift assay revealed that LPS or TNF-alpha increased binding activity for the NF-kappa B site. A slower-migrating complex binding to the CAAT box gave rise after exposure to LPS or forskolin. Competition assay suggested that this slower-migrating complex consisted of a heterodimer between a member of CAAT box/enhancer binding (C/EBP) protein family and cAMP responsive element binding protein (CREB). LPS or IL-6 increased binding complexes for the IRF site, which was compatible with induction of IRF-1. LPS, IL-6, or IFN-gamma induced a novel binding complex for GAS, which also existed in the 5'-flanking region of the IRF-1 gene. These data suggest that (1) iNOS induction simultaneously requires both NF-kappa B activation and IRF-1 induction, and (2) the heterodimer between C/EBP and CREB has synergistic effects on the iNOS induction via the CAAT box.
DOI https://doi.org/10.1161/01.RES.81.6.911
PMID 9400371