Effect of theophylline on airway inflammation in asthma

Abstract

AIM: To investigate whether low dose theophylline has an anti-inflammatory effect in asthma. METHODS: Nineteen asthmatic subjects were given 200 mg sustained-release theophylline preparation twice daily for 4 weeks. The mean serum concentration of theophylline was 7.9 mg/L. The percentage of eosinophils, EG2+ eosinophils, and the level of eosinophil cationic protein (ECP) in sputum pre- and post-administration were detected by Wright's stain, immunocytochemistry, and immuno-CAP system, and the symptom scores and lung function were evaluated as well. The above indices for 10 healthy subjects were regarded as control. RESULTS: Before using theophylline, sputum eosinophils, EG2+ eosinophils, and ECP in asthmatic group were much higher than those of healthy group. After four weeks' administration, there were great decreases in percentage of total eosinophils (40 % ± 17 % vs 29 % ± 11%, P <0.01), activated (EG2+) eosinophils (28 %±9 % vs 10 %±8 %, P<0.01) and in the concentration of sputum ECP [(373±206) vs (220±132) μg/L, P < 0.01]. The symptom scores decreased greatly (7.1±1.2 vs 5.4±1.6, P < 0.01). There was a marked increased in forced expiratory volume one second (FEV1.0) after administration (2.2 ±0.6 vs 2.4 ± 0.5, P < 0.01). The FEV1.0 % of asthmatic subjects after administration increased (60 % ± 13 % vs 65 % ± 13 %, P < 0.01), too. CONCLUSION: These results indicated that low dose theophylline had inhibitory action on airway inflammation in asthma with noticeable improvement of the patients' symptoms and lung function.