Adenosine receptors in COPD and asymptomatic smokers: effects of smoking cessation.
Our group has shown that 1-year smoking cessation persisted or increased airway inflammation in chronic obstructive pulmonary disease (COPD). We compared adenosine and adenosine receptor (AR) expression in COPD and asymptomatic smokers (AS) before and after 1-year smoking cessation. Sputum cytospins and bronchial biopsies of (ex)smoking COPD patients and AS were studied for A(1)R, A(2A)R, A(2B)R, and A(3)R expression. Adenosine and inflammatory mediators were measured in sputum supernatants. At baseline, COPD patients had lower levels of adenosine and higher levels of vascular endothelial growth factor in sputum than AS. Smoking cessation induced significantly different effects in COPD than in AS, i.e. an increase in percentages of A(3)R expressing neutrophils and A(1)R expressing macrophages in COPD as increase in adenosine and monocyte chemoattractant protein-1 levels in sputum. Adenosine-related effector mechanisms may contribute to the persistence and progression of airway inflammation in COPD following 1-year smoking cessation.
Versluis
Mieke
M
Department of Pathology, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB, Groningen, The Netherlands.
ten Hacken
Nick
N
Postma
Dirkje
D
Barroso
Begona
B
Rutgers
Bea
B
Geerlings
Marie
M
Willemse
Brigitte
B
Timens
Wim
W
Hylkema
Machteld
M
D000241:Adenosine / Q000378:metabolism; D000328:Adult; D001999:Bronchoscopy; D002851:Chromatography, High Pressure Liquid; D018450:Disease Progression; D005260:Female; D006801:Humans; D007249:Inflammation / Q000378:metabolism / Q000473:pathology; D018836:Inflammation Mediators / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000378:metabolism* / Q000473:pathology*; D018047:Receptors, Purinergic P1 / Q000378:metabolism*; D012907:Smoking / Q000009:adverse effects*; D016540:Smoking Cessation; D013183:Sputum / Q000737:chemistry / Q000378:metabolism
D018836:Inflammation Mediators; D018047:Receptors, Purinergic P1; D000241:Adenosine