In vivo antioxidant treatment protects against bleomycin-induced lung damage in rats

This study examines the activity of the antioxidant N-acetylcysteine on bleomycin-induced pulmonary fibrosis in rats with emphasis on the early inflammatory phase. Rats receiving N-acetylcysteine (300 mg kg−1 day−1, intraperitoneal) had less augmented lung wet weight, and lower levels of proteins, l...

Descripción completa

Detalles Bibliográficos
Autores: Serrano-Mollar, Anna, Closa, Daniel, Morcillo, Esteban J., Bulbena, Oriol
Tipo de recurso: artículo
Fecha de publicación:2003
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/2971
Acceso en línea:http://hdl.handle.net/10261/2971
Access Level:acceso abierto
Palabra clave:Pulmonary fibrosis
Bleomycin
Rat
N-acetylcysteine
Inflammation
Descripción
Sumario:This study examines the activity of the antioxidant N-acetylcysteine on bleomycin-induced pulmonary fibrosis in rats with emphasis on the early inflammatory phase. Rats receiving N-acetylcysteine (300 mg kg−1 day−1, intraperitoneal) had less augmented lung wet weight, and lower levels of proteins, lactate dehydrogenase, neutrophil and macrophage counts in bronchoalveolar lavage fluid and lung myeloperoxidase activity with a betterment of histological score at 3 days postbleomycin. A diminished lung GSH/GSSG ratio and augmented lipid hydroperoxides were observed 3 days postbleomycin. These changes were attenuated by N-acetylcysteine. Alveolar macrophages from bleomycin-exposed rats released augmented amounts of superoxide anion and nitric oxide. N-Acetylcysteine did not modify superoxide anion generation but reduced the increased production of nitric oxide. N-Acetylcysteine suppressed the bleomycin-induced increased activation of lung NF-κB (shift assay and immunohistochemistry), and decreased the augmented levels of the early inflammatory cytokines, tumour necrosis factor-α, interleukin-β, interleukin-6 and macrophage inflammatory protein-2 observed in bronchoalveolar lavage fluid at 1 and 3 days postbleomycin exposure. At 15 days postbleomycin, N-acetylcysteine decreased collagen deposition in bleomycin-exposed rats (hydroxyproline content: 6351±669 and 4626±288 μg per lung in drug vehicle- and N-acetylcysteine-treated rats, respectively; P<0.05). Semiquantitative histological assessment at this stage showed less collagen deposition in N-acetylcysteine-treated rats compared to those receiving bleomycin alone. These results indicate that N-acetylcysteine reduces the primary inflammatory events, thus preventing cellular damage and the subsequent development of pulmonary fibrosis in the bleomycin rat model.