Objective: Lung disease in cystic fibrosis (CF) is
characterized by a neutrophilic inflammatory response. This can lead to
the production of oxidants, and to oxidative stress in the lungs.
Glutathione (GSH) represents the primary intracellular antioxidant, and
provides an important defense in the epithelial lining fluid. Evidence
suggests that lymphocyte GSH reflects lung GSH concentrations, and so
could potentially serve as a peripheral marker of lung
Methods: We assessed peripheral blood
lymphocyte GSH concentrations in 20 children (13 boys) with CF who were
in stable condition at the time of evaluation. Values were compared
with nutritional status and lung function parameters.
Results: Patients were 11.7 ± 3.03 years old (mean±
SD). Their percentage of ideal body weight was 101.8 ± 17.92%;
FEV1, 79.5 ± 19.22% predicted; FEV1/FVC,
75.0 ± 10.08%; and residual volume (RV)/total lung capacity (TLC),
31.3 ± 10.47%. For the group, the GSH concentration was
1.31 ± 0.52 μmol/106 lymphocytes, which was not
different from laboratory control values. GSH values were correlated
with nutritional status (percentage of ideal body weight: r = 0.49,
p < 0.03) and the degree of gas trapping (RV/TLC: r = 0.50,
p < 0.03), and were correlated inversely with airflow limitation
(FEV1, percent predicted: r = −0.45, p < 0.05;
FEV1/FVC: r = −0.48, p < 0.04), but not with age,
height, or weight (p > 0.1).
interpret the inverse correlation between lymphocyte GSH concentration
and lung function as a reflection of upregulation of GSH production by
lung epithelial tissue in response to oxidative stress. We interpret
the correlation between lymphocyte GSH concentration and nutritional
status as a reflection of the role of cysteine in hepatic glutamine
metabolism. Peripheral blood lymphocyte GSH concentration may
potentially serve as a convenient marker of lung inflammation.
Furthermore, the increased demand for GSH production in the face of
ongoing inflammation suggests a potential role for supplementation with