TY - JOUR
T1 - Ozone, but not nitrogen dioxide, exposure decreases glutathione peroxidases in epithelial lining fluid of human lung
AU - Avissar, Nelly E.
AU - Reed, Christina K.
AU - Cox, Christopher
AU - Frampton, Mark W.
AU - Finkelstein, Jacob N.
PY - 2000
Y1 - 2000
N2 - Antioxidants, such as glutathione peroxidases (GPxs), in epithelial lining fluid (ELF) protect against health effects of oxidant pollutants, which includes O3 or NO2. We hypothesized that GPxs concentration in ELF is responsive to O3 or NO2 exposure. Subjects underwent two 4-h exposures to O3 (0.22 ppm) and one to air. In another experiment, subjects underwent 3-h exposures to air and NO2 (0.6 and 1.5 ppm). Bronchoalveolar lavage (BAL) was performed immediately or 18 h after O3 exposure and 3.5 h after each NO2 exposure. GPx activity and extracellular GPx (eGPx) protein concentrations were determined in ELF, and their relationships to markers of lung function, inflammation, and epithelial permeability were examined. Although the total amounts were not changed, basal (air) GPx activity (223.6 ± 24.4 mU/ml), basal eGPx protein concentration (2.62 ± 0.25 μg/ml), and basal ELF dilution factor (152.3 ± 8.4) decreased 40% immediately after O3 exposure and remained 30% decreased 18 h after exposure (p = 0.0001). No effect of NO2 exposure on GPxs concentration was detected. There was an inverse correlation between baseline ELF eGPx protein concentration and the change in PMN 18 h after O3 exposure (p = 0.04). Thus, O3, a strong oxidant, decreases both GPx activity and eGPx protein in ELF, whereas NO2, a weaker oxidant, does not. eGPx in ELF may protect against O3-induced airway inflammation.
AB - Antioxidants, such as glutathione peroxidases (GPxs), in epithelial lining fluid (ELF) protect against health effects of oxidant pollutants, which includes O3 or NO2. We hypothesized that GPxs concentration in ELF is responsive to O3 or NO2 exposure. Subjects underwent two 4-h exposures to O3 (0.22 ppm) and one to air. In another experiment, subjects underwent 3-h exposures to air and NO2 (0.6 and 1.5 ppm). Bronchoalveolar lavage (BAL) was performed immediately or 18 h after O3 exposure and 3.5 h after each NO2 exposure. GPx activity and extracellular GPx (eGPx) protein concentrations were determined in ELF, and their relationships to markers of lung function, inflammation, and epithelial permeability were examined. Although the total amounts were not changed, basal (air) GPx activity (223.6 ± 24.4 mU/ml), basal eGPx protein concentration (2.62 ± 0.25 μg/ml), and basal ELF dilution factor (152.3 ± 8.4) decreased 40% immediately after O3 exposure and remained 30% decreased 18 h after exposure (p = 0.0001). No effect of NO2 exposure on GPxs concentration was detected. There was an inverse correlation between baseline ELF eGPx protein concentration and the change in PMN 18 h after O3 exposure (p = 0.04). Thus, O3, a strong oxidant, decreases both GPx activity and eGPx protein in ELF, whereas NO2, a weaker oxidant, does not. eGPx in ELF may protect against O3-induced airway inflammation.
UR - http://www.scopus.com/inward/record.url?scp=0033773687&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033773687&partnerID=8YFLogxK
U2 - 10.1164/ajrccm.162.4.9912041
DO - 10.1164/ajrccm.162.4.9912041
M3 - Article
C2 - 11029342
AN - SCOPUS:0033773687
SN - 1073-449X
VL - 162
SP - 1342
EP - 1347
JO - American journal of respiratory and critical care medicine
JF - American journal of respiratory and critical care medicine
IS - 4 I
ER -