title: Early divergent lung antioxidant enzyme expression in response to lipopolysaccharide.
abstract: Lipopolysaccharide (LPS), a component of the cell wall of Gram-negative bacteria, interacts with eukaryotic cells, causing changes in gene expression and a rapid increase in the formation of superoxide and H2O2. We now report that, within 6 h of treating rats with LPS, there was a divergent response in the lung of manganese superoxide dismutase (Mn-SOD) and catalase expression without a change in expression of copper-zinc superoxide dismutase or glutathione peroxidase. The activity and mRNA concentration of Mn-SOD increased during the time catalase mRNA concentration and activity decreased. These divergent changes and activation of nuclear factor-kappa B (NF-kappa B) were preceded by a fall, 1 h after LPS treatment, in the RNA binding activity of two redox-sensitive proteins: Mn-SOD RNA binding protein and catalase RNA binding protein. The rapid onset of these changes, the bacteriostatic properties of H2O2, and the signaling function of NF-kappa B suggest that the divergent expression of Mn-SOD and catalase is a coordinated component of the acute phase reaction to bacterial invasion.
authors.affiliation: Department of Pediatrics and Medicine, Georgetown University School of Medicine, Washington, District of Columbia 20007, USA.
authors.forename: L B
authors.initials: LB
authors.lastname: Clerch
authors.forename: A
authors.initials: A
authors.lastname: Wright
authors.forename: D J
authors.initials: DJ
authors.lastname: Chung
authors.forename: D
authors.initials: D
authors.lastname: Massaro
mesh_terms: D000818:Animals; D000975:Antioxidants; D002374:Catalase / Q000096:biosynthesis*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D005979:Glutathione Peroxidase / Q000096:biosynthesis / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008168:Lung / Q000201:enzymology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000096:biosynthesis*
chemical_list: D000975:Antioxidants; D008070:Lipopolysaccharides; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase