TY - JOUR
T1 - Enhanced production of oxygen radicals in nocturnal asthma
AU - Jarjour, N. N.
AU - Busse, W. W.
AU - Calhoun, W. J.
PY - 1992
Y1 - 1992
N2 - Although the mechanisms of nocturnal worsening of pulmonary function in asthmatics have not been entirely established, airway inflammation is felt to be a major factor in disease severity. Consequently, to determine whether changes in bronchoalveolar lavage (BAL) fluid cellular components and their functions are related to nocturnal airway obstruction, we performed BAL at 4:00 A.M. and at 4:00 P.M. in asthma subjects with (n = 5) and without (n = 10) nocturnal asthma. No significant changes were observed from 4:00 P.M. to 4:00 A.M. in the concentration of total cells or the percentage or concentration of eosinophils or neutrophils in BAL fluid from subjects with or without nocturnal asthma. However, superoxide anion generation by air- space cells from subjects with nocturnal asthma was significantly greater at 4:00 A.M. than at 4:00 P.M. (6.9 ± 1.7 versus 1.8 ± 0.5 nmol/500K cells/h, p < 0.05). Moreover, superoxide production at 4:00 A.M. was greater in subjects with than in those without nocturnal asthma (6.9 ± 1.7 versus 2.2 ± 0.6, p < 0.02). Furthermore, in our group of asthmatics, the change in generation of superoxide anion from 4:00 P.M. to 4:00 A.M. was significantly correlated with the change in FEV1 (r = -0.71, p < 0.01). We conclude that the development of nocturnal airway obstruction in asthma is associated with enhanced production of oxygen radicals by air-space cells. Because oxygen radicals can cause airway injury and thus enhance bronchial obstruction, it is possible that the release of these reactive compounds is causally associated with nocturnal asthma.
AB - Although the mechanisms of nocturnal worsening of pulmonary function in asthmatics have not been entirely established, airway inflammation is felt to be a major factor in disease severity. Consequently, to determine whether changes in bronchoalveolar lavage (BAL) fluid cellular components and their functions are related to nocturnal airway obstruction, we performed BAL at 4:00 A.M. and at 4:00 P.M. in asthma subjects with (n = 5) and without (n = 10) nocturnal asthma. No significant changes were observed from 4:00 P.M. to 4:00 A.M. in the concentration of total cells or the percentage or concentration of eosinophils or neutrophils in BAL fluid from subjects with or without nocturnal asthma. However, superoxide anion generation by air- space cells from subjects with nocturnal asthma was significantly greater at 4:00 A.M. than at 4:00 P.M. (6.9 ± 1.7 versus 1.8 ± 0.5 nmol/500K cells/h, p < 0.05). Moreover, superoxide production at 4:00 A.M. was greater in subjects with than in those without nocturnal asthma (6.9 ± 1.7 versus 2.2 ± 0.6, p < 0.02). Furthermore, in our group of asthmatics, the change in generation of superoxide anion from 4:00 P.M. to 4:00 A.M. was significantly correlated with the change in FEV1 (r = -0.71, p < 0.01). We conclude that the development of nocturnal airway obstruction in asthma is associated with enhanced production of oxygen radicals by air-space cells. Because oxygen radicals can cause airway injury and thus enhance bronchial obstruction, it is possible that the release of these reactive compounds is causally associated with nocturnal asthma.
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U2 - 10.1164/ajrccm/146.4.905
DO - 10.1164/ajrccm/146.4.905
M3 - Article
C2 - 1329592
AN - SCOPUS:0026715083
SN - 1073-449X
VL - 146
SP - 905
EP - 911
JO - American Review of Respiratory Disease
JF - American Review of Respiratory Disease
IS - 4
ER -