Ionizing radiation potentiates the induction of nitric oxide synthase by interferon-gamma (Ifn-gamma) or Ifn-gamma and lipopolysaccharide in bnl cl.2 murine embryonic liver cells: role of hydrogen peroxide.
The effects of ionizing irradiation on the nitric oxide (NO) production in murine embryonic liver cell line, BNL CL.2 cells, were investigated. Various doses (5-40 Gy) of radiation made BNL CL.2 cells responsive to interferon-gamma alone for the production of NO in a dose-dependent manner. Small amounts of lipopolysaccharide (LPS) or tumor necrosis factor-alpha (TNF-alpha) synergized with IFN-gamma in the production of NO from irradiated BNL CL.2 cells, even though LPS or TNF-alpha alone did not induce NO production from the same cells. Immunoblots showed parallel induction of inducible nitric oxide synthase (iNOS). NO production in irradiated BNL CL.2 cells by IFN-gamma or IFN-gamma plus LPS was decreased by the addition of catalase, suggesting that H(2)O(2) produced by ionizing irradiation primed the cells to trigger NO production in response to IFN-gamma or IFN-gamma plus LPS. Furthermore, the treatment of nongamma-irradiated BNL CL.2 cells with H(2)O(2) made the cells responsive to IFN-gamma or IFN-gamma plus LPS for the production of NO. This study shows that ionizing irradiation has the ability to induce iNOS gene expression in responsive to IFN-gamma via the formation of H(2)O(2) in BNL CL.2 murine embryonic liver cells.
Yoo
J C
JC
Department of Microbiology and Immunology, Wonkwang University School of Medicine, and Medicinal Resource Research Center of Wonkwang University, Iksan, Chonbug, South Korea.
Pae
H O
HO
Choi
B M
BM
Kim
W I
WI
Kim
J D
JD
Kim
Y M
YM
Chung
H T
HT
D000818:Animals; D002460:Cell Line; D004622:Embryo, Mammalian; D004790:Enzyme Induction / Q000187:drug effects / Q000528:radiation effects; D005720:Gamma Rays; D006861:Hydrogen Peroxide / Q000378:metabolism; D007371:Interferon-gamma / Q000494:pharmacology*; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008099:Liver; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000494:pharmacology; D012477:Salmonella enteritidis; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D007371:Interferon-gamma; D006861:Hydrogen Peroxide; D019001:Nitric Oxide Synthase