[Expressions of cyclooxygenase-2 and matrix metalloproteinase-2 and airflow obstruction in patients with chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the expression of cyclooxygenase-2 (COX-2) and matrix metalloproteinase-2 (MMP-2) in induced sputum and airway obstruction in patients with stable chronic obstructive pulmonary disease (COPD).

METHODS: Fifty-five patients with stable COPD and 10 age-matched controls were enrolled in the study. Sputum induction was collected by inhalation of 3% sodium chloride. Cell numbers and differentials in sputum suspension were counted with Wright's stain. The concentrations of prostaglandin E(2) (PGE(2)) and MMP-2 in sputum supernatant were measured by ELISA. COX-2 protein expression in the cells was detected by Western blot.

RESULTS: The total sputum cells, the numbers of alveolar macrophages (AM) and neutrophils (Neu) in COPD patients were significantly higher than those in the control group (P < 0.05 or P < 0.01). The number of AM and Neu was inversely correlated with FEV(1)%pred and FEV(1)/FVC (r = -0.280, P < 0.05, r = -0.345, P < 0.01; r = -0.677, r = -0.773, all P < 0.01). The level of COX-2 protein expression was higher in induced sputum in COPD patients than that in the control group. Concentrations of PGE(2) in the control group and in COPD patients with grade 0, I, IIA, IIB and III were (81 +/- 18), (111 +/- 17), (117 +/- 23), (118 +/- 29), (153 +/- 24), (194 +/- 28) ng/L, respectively. Concentrations of MMP-2 in the control group and in COPD patients with grade 0, I, IIA, IIB and III were (0.7 +/- 0.4), (4.0 +/- 0.9), (4.5 +/- 1.5), (7.7 +/- 3.1), (11.9 +/- 3.5), (18.5 +/- 5.0)microg/L, respectively. Concentrations of PGE(2) and MMP-2 in sputum in COPD patients were significantly higher than those in the control group (all P < 0.01). PGE(2) and MMP-2 were inversely correlated with FEV(1)%pred, FEV(1)/FVC in stable COPD patients (r = -0.748, r = -0.750, P < 0.01; r = -0.801, r = -0.816, all P < 0.01). Concentrations of PGE(2) were positively correlated with MMP-2 in COPD patients (r = 0.775, P < 0.01).

CONCLUSIONS: (1) There is chronic inflammatory process in airway of stable COPD. AM and Neu contribute to the process. (2) COX-2 and MMP-2 may be involved in the airway inflammatory process and contribute to airway remodeling in COPD.