Sputum eicosanoid profiling in exacerbations of chronic obstructive pulmonary disease.
BACKGROUND
Eicosanoids are small lipid molecules with diverse biological functions in the airways.


OBJECTIVE
The aim of this study was to investigate changes in leukotriene B4 (LTB4), 8-isoprostane, prostaglandin E2 (PGE2) and cysteinyl-leukotriene (cys-LT) levels in the sputum of patients with chronic obstructive pulmonary disease (COPD) at the onset of a severe exacerbation and during the course of recovery.


METHODS
Thirty-seven ex-smoker COPD patients suffering an episode of acute exacerbation were enrolled. Samples were taken (i) on hospital admission and (ii) after regular treatment. Twenty-five stable ex-smoker COPD patients served as controls. Eicosanoids were determined by enzyme immunoassay.


RESULTS
Sputum PGE2 [39.8 (13.3-103.3) vs. 5.05 (2.3-12.1) pg/ml, p < 0.001], 8-isoprostane [89.5 (36.9-184.7) vs. 29.7 (13.8-68.8) pg/ml, p < 0.01] and LTB4 [587.7 (252.9-774.8) vs. 276.1 (105.4-594.7) pg/ml, p < 0.05] levels were increased in patients with exacerbation compared to stable subjects. After treatment only PGE2 levels decreased significantly [at discharge: 19.6 (4.6-52.5) pg/ml, p < 0.01], the levels of other eicosanoids remained elevated (p = NS). Sputum cys-LT levels were similar in stable patients and in those with exacerbation and treatment did not influence cys-LTs either. There was a significant correlation between PGE2 and sputum neutrophil and lymphocyte cell counts in patients with exacerbation.


CONCLUSIONS
Our results suggest that 8-isoprostane, LTB4 and PGE2 but not cys-LTs may be involved in exacerbation-associated inflammatory processes in the airways of patients with COPD. Validation of PGE2 for use as a biomarker of recovery from an exacerbation requires further studies.
Department of Pathophysiology, National Koranyi Institute of TB and Pulmonology, Budapest, Hungary.
Orsolya
O
Drozdovszky
Imre
I
Barta
Balazs
B
Antus
D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D003545:Cysteine / Q000378:metabolism*; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism*; D018450:Disease Progression; D015777:Eicosanoids / Q000378:metabolism; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007975:Leukotriene B4 / Q000378:metabolism*; D015289:Leukotrienes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000378:metabolism*; D013183:Sputum / Q000737:chemistry*
D015415:Biomarkers; D015777:Eicosanoids; D015289:Leukotrienes; C112381:cysteinyl-leukotriene; D007975:Leukotriene B4; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost; D015232:Dinoprostone; D003545:Cysteine