title: Involvement of nitric oxide in acute lung inflammation induced by cigarette smoke in the mouse.
abstract: Short-term exposure to cigarette smoke (CS) leads to acute lung inflammation (ALI) by disturbing oxidant/antioxidant balance. Both CS exposure and lung inflammation are important risk factors in the pathogenesis of chronic obstructive pulmonary disease. Nitric oxide (NO) is an oxidant both present in CS and produced in the inflammatory response, but its role in the effects of CS exposure is unclear. Our aim was to study involvement of NO in a model of CS exposure. Groups of mice (male C57BL/6) exposed to CS (six cigarettes per day over five days) were simultaneously subjected to treatment with vehicle (CS), 60mg/kg/day omega-nitro-l-arginine methyl ester (CS+l-NAME), 20mg/kg/day nitroglycerine (CS+NTG), or 120mg/kg/day l-arginine (CS+l-arg). Bronchoalveolar lavage fluid was then aspirated to perform cell counts, and malondialdehyde (MDA), nitrite, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels were measured in lung homogenates. Macrophage and neutrophil counts were increased in the CS (p<0.001) and CS+l-NAME groups (p<0.05 and p<0.01, respectively); the CS+NTG and CS+l-arg groups showed no differences from the control group. MDA was increased in the CS (p<0.05) and CS+l-NAME (p<0.01) groups when compared to the control group. Nitrite levels were decreased in the CS and CS+l-NAME groups (p<0.001) and increased in the CS+NTG (p<0.001) and CS+l-arg (p<0.01) groups when compared to the control. CAT, SOD and GPx activities in the CS and CS+l-NAME groups were all significantly increased compared to the control group. Our results suggest that administration of NO donors or substrates may be a useful therapy in the treatment of ALI caused by CS.
authors.affiliation: Laboratory of Tissue Repair, Department of Histology and Embryology, Rio de Janeiro State University, Brazil.
authors.forename: Samuel Santos
authors.initials: SS
authors.lastname: Valença
authors.forename: Wagner Alves
authors.initials: WA
authors.lastname: Pimenta
authors.forename: Carlos Romualdo
authors.initials: CR
authors.lastname: Rueff-Barroso
authors.forename: Thiago Santos
authors.initials: TS
authors.lastname: Ferreira
authors.forename: Angela Castro
authors.initials: AC
authors.lastname: Resende
authors.forename: Roberto Soares de
authors.initials: RS
authors.lastname: Moura
authors.forename: Luís Cristóvão
authors.initials: LC
authors.lastname: Porto
mesh_terms: D000208:Acute Disease; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002374:Catalase / Q000378:metabolism; D002452:Cell Count; D005979:Glutathione Peroxidase / Q000378:metabolism; D008264:Macrophages / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D019331:NG-Nitroarginine Methyl Ester / Q000378:metabolism; D009504:Neutrophils / Q000473:pathology; D009569:Nitric Oxide / Q000378:metabolism*; D011014:Pneumonia / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D012906:Smoke / Q000009:adverse effects*; D013482:Superoxide Dismutase / Q000378:metabolism; D014026:Nicotiana
chemical_list: D012906:Smoke; D009569:Nitric Oxide; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D019331:NG-Nitroarginine Methyl Ester