Submitted on February 27, 2008
Revised on April 30, 2008
Accepted on May 1, 2008
Effect of an Inhaled Glucocorticoid on Endothelial Function in Healthy Smokers
Eliana S Mendes1*, Gabor Horvath2, Patricia Rebolledo2, Maria Elena Monzon1, S Marina Casalino-Matsuda1, and Adam Wanner1
1 University of Miami
2 University fo Miami
* To whom correspondence should be addressed. E-mail: emendes{at}med.miami.edu.
Cigarette smoking is associated with attenuated endothelium-dependent vasodilation (endothelial dysfunction) in the systemic circulation including the airway circulation. We wished to determine if an inhaled corticosteroid (ICS) could restore endothelial function in the airway of lung-healthy current smokers, ex-smokers and non-smokers. We measured baseline airway blood flow (Qaw) and Qaw reactivity to inhaled albuterol as an index of endothelium-dependent vasodilation and to sublingual nitroglycerin as an index of endothelium-independent vasodilation in lung-healthy current smokers, ex-smokers and non-smokers. Current smokers were then treated with inhaled fluticasone for 3 weeks, and all measurements were repeated after fluticasone treatment and after a subsequent 3-week fluticasone washout period. Baseline mean Qaw and endothelium-independent Qaw reactivity were similar in the three groups. Mean endothelium-dependent Qaw reactivity was 49.5% in non-smokers, 42.7% in ex-smokers, and 10.8% in current smokers (p<0.05 vs. non-smokers). In current smokers, mean baseline Qaw was unchanged after fluticasone treatment, but endothelium-dependent Qaw reactivity significantly increased to 34.9%. Qaw reactivity was again blunted after fluticasone washout. Endothelial dysfunction as assessed by vascular reactivity can be corrected with an ICS in the airway of lung-healthy current smokers. This proof of concept can serve as the basis for future clinical investigations on the effect of glucocorticoids on endothelial function in smokers.
