Interleukin-1 beta-induced nitric oxide synthase expression by rat pancreatic beta-cells: evidence for the involvement of nuclear factor kappa B in the signaling mechanism. Endocrinology 1995 Nov;136(11):4790-5
Date
11/01/1995Pubmed ID
7588208DOI
10.1210/endo.136.11.7588208Scopus ID
2-s2.0-0028973284 (requires institutional sign-in at Scopus site) 160 CitationsAbstract
Recent evidence indicates that overproduction of nitric oxide mediates cytokine-induced inhibition of insulin secretion by pancreatic islets. The current studies were designed to characterize signaling events involving the transcriptional factor NFkappaB in interleukin-1 (IL-1)-induced expression of inducible nitric oxide synthase (iNOS) by primary and transformed rat pancreatic beta-cells. Due to limitations of cell numbers of purified primary beta-cells, biochemical and molecular studies were performed primarily using the insulinoma cell line, RINm5F. Inhibitors of NFkappaB, diethyldithiocarbamate, pyrrolidine dithiocarbamate, and N-acetyl cysteine prevent IL-1-induced iNOS expression at the level of messenger RNA, protein, and nitrite generation. IL-1 induces a time-dependent translocation of NFkappaB from cytosol to nucleus, with maximal translocation observed approximately 15-30 min after IL-1 treatment, as determined by electrophoretic mobility shift assays. The specificity of the band containing the NF kappa B DNA-protein complex was shown by competition with a 150-fold excess of nonradiolabeled NF kappa B oligonucleotide. Supershift assays using immunoglobulins G against NF kappa b subunits p50 an p65 indicate that the protein complex contains a heterodimer of p50 and p65. IL-1-induced translocation of NF kappa B was blocked by 100 microns 100 microM diethyldithiocarbamate or 100 microM pyrrolidine dithiocarbamate, further establishing a critical role for NF kappa B in the induction of iNOS by IL-1 in rat pancreatic beta-cells. Activation of tyrosine kinase appears to precede NF kappa B activation, as the tyrosine kinase inhibitor genistein (100 microM) blocks IL-1-induced translocation of NF kappa B. An understanding of the signal transduction pathway of cytokine-induced nitric oxide generation by beta-cells will provide strategies of intervention to further evaluate the role of nitric oxide in mediating beta-cell dysfunction.
Author List
Kwon G, Corbett JA, Rodi CP, Sullivan P, McDaniel MLAuthor
John A. Corbett PhD Chair, Professor in the Biochemistry department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBase Sequence
Ditiocarb
Enzyme Activation
Enzyme Inhibitors
Gene Expression
Genistein
Insulinoma
Interleukin-1
Islets of Langerhans
Isoflavones
Male
Molecular Sequence Data
NF-kappa B
Nitric Oxide Synthase
Pancreatic Neoplasms
Protein-Tyrosine Kinases
Rats
Rats, Sprague-Dawley
Signal Transduction
Tumor Cells, Cultured
