Once-daily theophylline reduces serum eosinophil cationic protein and eosinophil levels in induced sputum of asthmatics.
BACKGROUND
Because eosinophilic airway inflammation is a characteristic feature of bronchial asthma, the treatment of airway inflammation is important in the management of asthma. Theophylline has been reported to reduce airway inflammation, in addition to its well-known bronchodilating effect.


OBJECTIVE
In order to evaluate the effects of theophylline on airway inflammation, we investigated 48 subjects with mild and moderate asthma.


METHODS
The patients were randomly divided into two groups, with or without theophylline treatment (control n = 24; theophylline, n = 24). We examined the level of serum eosinophil cationic protein (ECP), induced sputum samples, and peak expiratory flow (PEF) and obtained spirograms before and after 4 weeks of treatment with once-daily theophylline (200-600 mg/day) of subjects with mild or moderate asthma.


RESULTS
Theophylline significantly increased morning and evening PEF and significantly decreased the diurnal variation of PEF. After treatment with theophylline, both serum ECP and the percentage of eosinophils in induced sputum were significantly decreased. In contrast, peripheral blood eosinophil count was unchanged after treatment with theophylline.


CONCLUSIONS
These findings suggest that theophylline reduces airway inflammation and the severity of asthma, presumably via suppression of both eosinophil activity and subsequent eosinophil infiltration of the airways.
Aizawa
H
H
Clinical Research Institute, National Fukuoka-Higashi Hospital, Faculty of Medicine, Kyushu University, Fukuoka, Japan. aizawah@fukuokae.hosp.go.jp
Iwanaga
T
T
Inoue
H
H
Takata
S
S
Matsumoto
K
K
Takahashi
N
N
Yoshida
M
M
Hara
N
N
D000293:Adolescent; D000328:Adult; D000368:Aged; D001249:Asthma / Q000097:blood / Q000188:drug therapy* / Q000276:immunology; D001798:Blood Proteins / Q000032:analysis*; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D047091:Eosinophil Granule Proteins; D004804:Eosinophils / Q000187:drug effects* / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012260:Ribonucleases; D013183:Sputum / Q000166:cytology* / Q000276:immunology; D013806:Theophylline / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*
D001798:Blood Proteins; D001993:Bronchodilator Agents; D047091:Eosinophil Granule Proteins; D013806:Theophylline; D012260:Ribonucleases