Systemic markers of the redox balance in chronic obstructive pulmonary disease

Abstract

Chronic obstructive pulmonary disease (COPD) is highly prevalent and its pathogenesis is still not completely clarified. Clinically stable patients (n=21) and healthy subjects (n=24) were studied for blood markers of oxidative injury and antioxidant status. The plasma concentration of protein carbonyls was significantly increased in COPD patients, both ex-smokers (0.76 +/- 0.28 nmol mg(-1)) and smokers (0.99 +/- 020 nmol mg(-1)) versus controls (0.49 +/- 0.14 nmol mg(-1)) . The concentration of total thiols was slightly enhanced in plasma of the COPD patients (ex-smokers 492 +/- 23 micromol 1(-1) and smokers 505 +/- 36 micromol 1(-1) versus controls 450 +/- 67 micromol 1(-1); p < 0.05). The activity of the antioxidant enzyme superoxide dismutase was increased in erythrocytes (activity in U g(-1) haemoglobin; ex-smokers 4460 +/- 763 and smokers 4114+/- 1060 versus 3015 +/- 851 in controls; p > 0.01), while glutathione peroxidase activity was decreased in total blood (activity in U g(-1) haemoglobin: ex-smokers 27 +/- 9 and smokers 23 +/- 9 versus 47 +/- 25; p < 0.01). Lower levels of selenium in plasma were also found for COPD patients (concentration in mg 1(-1): ex-smokers 0.030 +/- 0.019 and smokers 0.032 +/- 0.024 versus 0.058 +/- 0.023 in controls; p < 0.01), being more evident in those with very low levels of arterial oxygen pressure. In addition, the levels of potassium and rubidium were increased in blood cells of the patient group. All these changes might reflect oxidant damage and an altered electrolytic homeostasis, and can be interpreted as markers of COPD rather than as indicators of smoking habits.

Oxidative stress in patients with COPD and pulmonary hypertension

“…Our finding of lower GPX activity in patients with COPD than in healthy persons is in agreement with previous studies [19,26]. Interestingly, both animal and human studies suggest that antioxidant enzymes might play a role in pulmonary vascular physiology and pathology.…”

Role of oxidative stress and serum lipid levels in stable chronic obstructive pulmonary disease

“…We found that serum TOS levels of COPD patients were significantly higher than those of control individuals. Santos et al 25 found that the plasma concentration of protein carbonyls was significantly increased in COPD patients compared to that in control individuals. The activity of antioxidant enzyme superoxide dismutase was increased in erythrocytes, while glutathione peroxidase activity was decreased in total blood.…”

8‐Hydroxy‐2′‐deoxyguanosine (8‐OH‐dG) as a potential survival biomarker in patients with nonsmall‐cell lung cancer

“…5 Cigarette smoke also contains free radicals and induces oxidative DNA damage. 6 Oxidative DNA damage is thought to play a major role in carcinogenesis. 7 The level of 8-hydroxy-2 0 -deoxyguanosine (8-OH-dG), products of oxidative DNA damage, has been suggested to be a good indicator of oxidative stress in humans.…”