![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
Exposure to high oxygen concentration produces toxicity by free radical release. We aimed to study: whether stable chronic obstructive pulmonary disease (COPD) patients present an unbalance in the blood redox status; the effect of oxygen administration on blood redox balance; the efficacy of N-acetyl-cysteine (NAC) treatment against the oxidative stress-induced by oxygen administration and whether it is dose-related. To this, 45 stable state III COPD patients were recruited and reduced glutathione (GSH) and oxidised glutathione (GSSG) in erythrocytes and thiol proteins (P-SH) and carbonyl proteins (PC) in both erythrocytes and plasma were evaluated. All COPD patients underwent 2 l/m oxygen for 18 h and NAC at 1200 or 1800 mg/day or placebo for 48 h starting with oxygen administration. Blood samples were collected at basal conditions, after 8 and 18 h of oxygen administration and 24 h after oxygen withdrawal. Results: COPD patients present an unstable redox equilibrium mainly due to plasma sulphydryl protein depletion. Oxygen administration oxidize erythrocyte GSH, decrease P-SH and increase PC levels in both plasma and erythrocytes. NAC administration counteract the oxidative stress and at the highest dose completely prevent protein oxidation. In conclusion, stable state III COPD patients present an unstable redox balance; long term low flow oxygen administration induces systemic oxidative stress, which is prevented by NAC treatment.
| Abbreviations | ||
| COPD | = | chronic obstructive pulmonary disease |
| FEV1 | = | forced expiratory volume in one second |
| FVC | = | forced vital capacity |
| GSH | = | reduced glutathione |
| GSSG | = | oxidised glutathione |
| NAC | = | N-acetyl-cysteine |
| PC | = | carbonyl proteins |
| P-SH | = | thiol proteins |
| RBC | = | red blood cells |
| Abbreviations | ||
| COPD | = | chronic obstructive pulmonary disease |
| FEV1 | = | forced expiratory volume in one second |
| FVC | = | forced vital capacity |
| GSH | = | reduced glutathione |
| GSSG | = | oxidised glutathione |
| NAC | = | N-acetyl-cysteine |
| PC | = | carbonyl proteins |
| P-SH | = | thiol proteins |
| RBC | = | red blood cells |
Notes
† Maria Pia Foschino-Barbaro and Gaetano Serviddio equally contributed to this work.