Glutathione and glutathione peroxidase in sputum samples of adult patients with cystic fibrosis.
BACKGROUND
Reduced glutathione (GSH) is a major antioxidant in the lung. In cystic fibrosis (CF) patients, extracellular GSH levels of lower airways, obtained by bronchoalveolar lavage (BAL), were reported to be lower than non-CF individuals.


METHODS
Upper airway secretions of stable adult CF patients (29 spontaneous and 13 induced sputum) and non-CF individuals (14 healthy and 12 asthmatics; all induced sputum) were analyzed for total glutathione (i.e. the sum of reduced, GSH, and oxidized, GSSG, forms), GSH and GSSG levels by enzymatic kinetic assay.


RESULTS
In CF, both spontaneous and induced sputum samples were comparable in total glutathione levels which were surprisingly high (median concentration of 9.2 (range 1.4-65.2) and 11.6 (1.1-69.8) microM, respectively). In non-CF individuals, total glutathione levels were significantly lower (healthy 2.8 (1.0-12.3), asthmatics (5.3 (1.3-19.2) microM; p<0.001, both vs. CF). In CF, more than 90% of total glutathione was represented by GSH, whereas in non-CF controls, GSH made up less than 50% of total glutathione (p<0.001).


CONCLUSIONS
In contrast to BAL, CF sputum contains high levels of GSH. Sputum induction is a potentially useful procedure to monitor antioxidant levels in upper airways of CF patients.
Dauletbaev
N
N
Pulmonary Medicine, Hospital of Johann Wolfgang Goethe University, Frankfurt/Main, Germany.
Viel
K
K
Buhl
R
R
Wagner
T O F
TO
Bargon
J
J
D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000378:metabolism*; D005260:Female; D005978:Glutathione / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006801:Humans; D008297:Male; D010084:Oxidation-Reduction; D013183:Sputum / Q000201:enzymology
D000975:Antioxidants; D005979:Glutathione Peroxidase; D005978:Glutathione