Reduction of nitric oxide synthase 2 expression by distamycin A improves survival from endotoxemia.

Abstract

NO synthase 2 (NOS2) plays an important role in endotoxemia through overproduction of NO. Distamycin A (Dist A) belongs to a class of drugs termed minor-groove DNA binders, which can inhibit transcription factor binding to AT-rich regions of DNA. We and others have previously shown that AT-rich regions of DNA surrounding transcription factor binding sites in the NOS2 promoter are critical for NOS2 induction by inflammatory stimuli in vitro. Therefore, we hypothesized that Dist A would attenuate NOS2 up-regulation in vivo during endotoxemia and improve animal survival. C57BL/6 wild-type (WT) mice treated with Dist A and LPS (endotoxin) showed significantly improved survival compared with animals treated with LPS alone. In contrast, LPS-treated C57BL/6 NOS2-deficient (NOS2-/-) mice did not benefit from the protective effect of Dist A on mortality from endotoxemia. Treatment with Dist A resulted in protection from hypotension in LPS-treated WT mice, but not in NOS2-/- mice. Furthermore, LPS-induced NOS2 expression was attenuated in vivo (WT murine tissues) and in vitro (primary peritoneal and RAW 264.7 murine macrophages) with addition of Dist A. Dist A selectively decreased IFN regulatory factor-1 DNA binding in the enhancer region of the NOS2 promoter, and this IFN regulatory factor-1 site is critical for the effect of Dist A in attenuating LPS induction of NOS2. Our data point to a novel approach in modulating NOS2 expression in vivo during endotoxemia and suggest the potential for alternative treatment approaches for critical illness.

• Authors: Rebecca M Baron, Irvith M Carvajal, Xiaoli Liu, Rachel O Okabe, Laura E Fredenburgh, Alvaro A Macias, Yen-Hsu Chen, Kuniaki Ejima, Matthew D Layne, Mark A Perrella
• Journal: Journal of immunology (Baltimore, Md. : 1950) (J Immunol) Vol. 173 Issue 6 Pg. 4147-53 (Sep 15 2004) ISSN: 0022-1767 [Print] United States
• PMID: 15356165 (Publication Type: Comparative Study, Journal Article, Research Support, U.S. Gov't, P.H.S.)
• Copyright: Copyright 2004 The American Association of Immunologists, Inc.

Chemical References

• DNA-Binding Proteins
• Distamycins
• Enzyme Inhibitors
• Interferon Regulatory Factor-1
• Irf1 protein, mouse
• Lipopolysaccharides
• Phosphoproteins
• stallimycin
• Interferon-gamma
• Nitric Oxide Synthase
• Nitric Oxide Synthase Type II
• Nos2 protein, mouse

Topics

• Animals
• Cell Line
• Cells, Cultured
• DNA-Binding Proteins (antagonists & inhibitors, metabolism, physiology)
• Disease Models, Animal
• Distamycins (pharmacology)
• Endotoxemia (enzymology, genetics, mortality, prevention & control)
• Enzyme Induction (drug effects)
• Enzyme Inhibitors (pharmacology)
• Gene Expression Regulation (drug effects, immunology)
• Hypotension (enzymology, genetics, prevention & control)
• Interferon Regulatory Factor-1
• Interferon-gamma (pharmacology)
• Lipopolysaccharides (antagonists & inhibitors, toxicity)
• Macrophages, Peritoneal (drug effects, enzymology)
• Male
• Mice
• Mice, Inbred C57BL
• Mice, Knockout
• Nitric Oxide Synthase (antagonists & inhibitors, biosynthesis, deficiency, genetics)
• Nitric Oxide Synthase Type II
• Phosphoproteins (antagonists & inhibitors, metabolism, physiology)
• Promoter Regions, Genetic (drug effects)
• Protein Binding (drug effects, genetics)