Circulating angiopoietin-1 and -2 in patients with stable and exacerbated asthma

Abstract

BACKGROUND: Angiopoietin (Ang)-1 and -2 are involved in the pathogenesis of asthma and have been identified as markers of asthma severity. OBJECTIVE: To determine the relation between circulating angiopoietins and clinical variables of patients with asthma. METHODS: Fifty patients with bronchial asthma and 25 healthy controls were enrolled. Ang1 and Ang2 plasma levels were analyzed in patients with stable and exacerbated asthma. RESULTS: Plasma Ang1 levels were 28.4 +/- 4.01 pg/mg in patients with bronchial asthma and 21.2 +/- 5.21 pg/mg in healthy controls. Plasma Ang2 levels were 23.96 +/- 1.38 pg/mg in patients with bronchial asthma compared with 36.8 +/- 4.46 pg/mg in healthy controls (P = .010). The ratio of Ang2 to Ang1 was lower in patients with asthma than in control subjects. Plasma Ang1 concentrations were correlated with the ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC), and plasma Ang2 levels were correlated with FEV1 percentage of predicted, FEV1/FVC, and total immunoglobulin E values. The ratio of Ang2 to Ang1 was correlated with FEV1 percentage of predicted and FEV1/FVC. Although plasma Ang1 levels tended to be lower in the exacerbated state than in the stable state in patients with asthma, Ang2 levels were higher in the exacerbated state than in the stable state in patients with asthma (P = .001). Plasma Ang2 levels were correlated with initial eosinophil proportions and initial neutrophil proportions. Plasma Ang2 levels and the ratio of Ang2 to Ang1 were correlated with blood eosinophil proportions in the exacerbated state. CONCLUSION: These results indicate that circulating angiopoietins could be a useful marker of asthma exacerbation.