Induced sputum metalloproteinases and their inhibitors in relation to exhaled nitrogen oxide and sputum nitric oxides and other inflammatory cytokines in patients with chronic obstructive pulmonary disease.

The aim of this study was to assess sputum levels of the metalloproteinases MMP-1, MMP-2, MMP-3, TIMP-1, and TIMP-2, as well as MMPs/TIMPs ratios in relation to exhaled NO (eNO) and sputum NOs (nitrates and nitrites) and IL8 obtained from chronic obstructive pulmonery disease (COPD) patients, healthy non-smokers, and healthy smokers. We found higher levels of TIMP-1 (118.9 ng/ml) and TIMP-2 (3.75 ng/ml) in COPD patients than in healthy smokers (17.7 ng/ml, P<0.03; 0.51 ng/ml, P>0.05, respectively) and healthy non-smokers (84.6 ng/ml, P>0.05; 1.61 ng/ml, P>0.05, respectively). We also observed significant positive correlations between concentrations of NOs and MMP-1, MMP-2, MMP-3, and TIMP-2 (r=0.37, P<0.02; r=0.60, P<0.0001; r=0.56, P<0.0004 and r=0.47 P<0.004, respectively) in COPD patients. IL8, MMP-2, MMP-3, and TIMP-2 levels in induced sputum were negatively correlated with airway obstruction, i.e., FEV(1)/FVC (r=-0.61, P<0.00009; r=-0.41, P<0.01; r=-0.38, P<0.02; r=-0.49, P<0.002). Our study points to a potentially pathogenic role of stromelysin-1 (MMP-3) in COPD.