PT - JOURNAL ARTICLE AU - Lanzetti, Manuella AU - Costa, Cristiane AU - Victoni, Tatiana AU - Nesi, Renata AU - Lopes, Alan AU - Alves, Jackson AU - Martins, Vanessa AU - Resende, Angela AU - Lagente, Vincent AU - Porto, Luís AU - Valenca, Samuel TI - Involvement of oxidative and nitrosative stress in the development of proteolytic pulmonary emphysema DP - 2012 Sep 01 TA - European Respiratory Journal PG - P3739 VI - 40 IP - Suppl 56 4099 - http://erj.ersjournals.com/content/40/Suppl_56/P3739.short 4100 - http://erj.ersjournals.com/content/40/Suppl_56/P3739.full SO - Eur Respir J2012 Sep 01; 40 AB - Our aim was to investigate the participation of oxidative stress in elastase-induced pulmonary emphysema. C57BL/6 mice were submitted to pancreatic porcine elastase (PPE) instillation (0.05U or 0.5U) per mouse (i.t.) to induce pulmonary emphysema. A separated group of mice were treated with aminoguanidine 1% (AMG). Lungs were collected on days 7, 14 and 21 after PPE instillation. Control group was sham-injected. We performed BAL, biochemical analyses of oxidative stress, and lung stereology and morphometry. Emphysema was histologically characterized at 21 days after 0.5 U of PPE, presenting increased alveolar linear intercept and volume density of airspaces in comparison with the control group. TNF-α was elevated at 7 and 14 days after PPE 0.5 U, concomitant with reduction in the IL-10 levels at the same time-points. Myeloperoxidase was elevated in all groups treated with 0.5 U of PPE. A contribution of oxidative stress at early stage of emphysema was observed with increased levels of nitrite, malondialdehyde and superoxide dismutase activity at 7 days after PPE 0.5 U. Glutathione peroxidase activity was increased in all groups treated with 0.5 U of PPE. With iNOS inhibition by AMG 1%, emphysema was attenuated. Furthermore, the proteolytic stimulus by PPE enhanced expression of nitrotyrosine and iNOS, while the group PPE+AMG showed low expression of iNOS and nitrotyrosine. PPE stimulus also induced eNOS expression, but AMG reduced it. Our results suggest a pathway of oxidative and nitrosative stress by nitric oxide production via iNOS expression in pulmonary emphysema.