RESUMEN
BACKGROUND: Cigarette smoke is strongly associated with NSCLC, but the carcinogenesis of NSCLC is poorly understood. METHODS: To discover the role of oxidative stress and anti-oxidative defense in NSCLC, we measured NADPH oxidase (NOX) activity, myeloperoxidase activity, 8-OHdG, and glutathione content from lung specimens. These came from 32 patients: 22 NSCLC patients and ten controls without cancer. RESULTS: In NSCLC patients, NOX activity was significantly higher both in the malignant (p = 0.001) and non-malignant (p = 0.044) samples from NSCLC patients, than in the control specimens. Myeloperoxidase activity was lower (p = 0.001) and glutathione content (p = 0.009) higher in malignant tissue. No significant difference was observable in 8-OHdG content between patient groups. CONCLUSIONS: Increase in NOX activity in the malignant tissues was independent of smoking history and myeloperoxidase activity, suggesting its independent role in NSCLC pathogenesis.
Asunto(s)
Adenocarcinoma/enzimología , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Carcinoma de Células Escamosas/enzimología , Glutatión/metabolismo , Neoplasias Pulmonares/enzimología , NADPH Oxidasas/metabolismo , Estrés Oxidativo , Peroxidasa/metabolismo , 8-Hidroxi-2'-Desoxicoguanosina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antioxidantes/metabolismo , Estudios de Casos y Controles , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fumar/efectos adversos , Adulto JovenRESUMEN
BACKGROUND: The major contribution to oxidant related lung damage in COPD is from the oxidant/antioxidant imbalance and possibly impaired antioxidant defence. Glutathione (GSH) is one of the most important antioxidants in human lung and lung secretions, but the mechanisms participating in its homeostasis are partly unclear. Glutathione-S-transferase omega (GSTO) is a recently characterized cysteine containing enzyme with the capability to bind and release GSH in vitro. GSTO has not been investigated in human lung or lung diseases. METHODS: GSTO1-1 was investigated by immunohistochemistry and Western blot analysis in 72 lung tissue specimens and 40 sputum specimens from non-smokers, smokers and COPD, in bronchoalveolar lavage fluid and in plasma from healthy non-smokers and smokers. It was also examined in human monocytes and bronchial epithelial cells and their culture mediums in vitro. RESULTS: GSTO1-1 was mainly expressed in alveolar macrophages, but it was also found in airway and alveolar epithelium and in extracellular fluids including sputum supernatants, bronchoalveolar lavage fluid, plasma and cell culture mediums. The levels of GSTO1-1 were significantly lower in the sputum supernatants (p = 0.023) and lung homogenates (p = 0.003) of COPD patients than in non-smokers. CONCLUSION: GSTO1-1 is abundant in the alveolar macrophages, but it is also present in extracellular fluids and in airway secretions, the levels being decreased in COPD. The clinical significance of GSTO1-1 and its role in regulating GSH homeostasis in airway secretions, however, needs further investigations.
Asunto(s)
Glutatión Transferasa/biosíntesis , Pulmón/enzimología , Enfermedad Pulmonar Obstructiva Crónica/enzimología , Esputo/enzimología , Anciano , Líquido del Lavado Bronquioalveolar , Línea Celular Tumoral , Femenino , Glutatión Transferasa/genética , Humanos , Pulmón/patología , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/patología , Fumar/genética , Fumar/metabolismo , Fumar/patologíaRESUMEN
BACKGROUND: One typical feature in chronic obstructive pulmonary disease (COPD) is the disturbance of the oxidant/antioxidant balance. Glutaredoxins (Grx) are thiol disulfide oxido-reductases with antioxidant capacity and catalytic functions closely associated with glutathione, the major small molecular weight antioxidant of human lung. However, the role of Grxs in smoking related diseases is unclear. METHODS: Immunohistochemical and Western blot analyses were conducted with lung specimens (n = 45 and n = 32, respectively) and induced sputum (n = 50) of healthy non-smokers and smokers without COPD and at different stages of COPD. RESULTS: Grx1 was expressed mainly in alveolar macrophages. The percentage of Grx1 positive macrophages was significantly lower in GOLD stage IV COPD than in healthy smokers (p = 0.021) and the level of Grx1 in total lung homogenate decreased both in stage I-II (p = 0.045) and stage IV COPD (p = 0.022). The percentage of Grx1 positive macrophages correlated with the lung function parameters (FEV1, r = 0.45, p = 0.008; FEV1%, r = 0.46, p = 0.007, FEV/FVC%, r = 0.55, p = 0.001). Grx1 could also be detected in sputum supernatants, the levels being increased in the supernatants from acute exacerbations of COPD compared to non-smokers (p = 0.013) and smokers (p = 0.051). CONCLUSION: The present cross-sectional study showed that Grx1 was expressed mainly in alveolar macrophages, the levels being decreased in COPD patients. In addition, the results also demonstrated the presence of Grx1 in extracellular fluids including sputum supernatants. Overall, the present study suggests that Grx1 is a potential redox modulatory protein regulating the intracellular as well as extracellular homeostasis of glutathionylated proteins and GSH in human lung.