Chronic Obstructive Pulmonary Disease (COPD), a lung disease related to smoking, is one of the leading causes of chronic morbidity and mortality around the world. One goal in COPD research is the identification of biomarkers for early diagnosis of the disease. Here, we sought COPD-specific changes in the proteome from human lung tissue. This revealed increased levels of surfactant protein A (SP-A) in COPD but not in the normal or fibrotic lung. The results were confirmed by immunohistochemistry, morphometry and Western blotting. Furthermore, elevated SP-A protein levels were detected from the induced sputum supernatants of COPD patients. The levels of other surfactant proteins (SP-B, SP-C, SP-D) were not altered. Our results suggest that SP-A is linked to the pathogenesis of COPD and could be considered as a potential COPD biomarker.

This study compares the nicotine patch to placebo in young adult light smokers, and the nicotine patch to varenicline in heavy smokers. Volunteer daily smokers were recruited into a randomized, placebo-controlled study via community media, colleges and the army (aged 18-26 years). Those subjects with light tobacco dependence were randomized to (i) placebo patch (n = 86) and (ii) nicotine patch 10 mg/16 hr for 8 weeks (n = 94), and those with stronger dependence to (iii) nicotine patch 15 mg/16 hr for 8 weeks (n = 51) and (iv) varenicline for 12 weeks (n = 60). The primary outcome variable was self-reported smoking abstinence at week 12. Secondary outcome variables were self-reported smoking abstinence at weeks 4 and 26, and self-reported abstinence verified by saliva cotinine level at week 12. The prevalence of self-reported smoking abstinence did not differ statistically significantly in light smokers during the follow-up (week 4: 19.8% for placebo patch and 26.6% for nicotine patch 10 mg/16 hr; week 12: 17.4% versus 23.4%; week 26: 15.1% versus 20.2%), but the groups of heavy smokers differed significantly for 12 weeks (week 4: 19.6% for nicotine patch 15 mg/16 hr and 73.3% for varenicline, p < 0.001; week 12: 15.7% versus 36.7%, p = 0.018). This statistically significant difference did not endure for the entire follow-up (week 26: 9.8% versus 18.3%, p = 0.280). However, saliva cotinine verified abstinence at week 12 did not support self-reported abstinence. Varenicline may be more effective than the nicotine patch as a smoking cessation pharmacotherapy among young adult heavy smokers in the short-term.

BackgroundThe receptor for advanced glycation end-products (RAGE) is highly expressed in the lung, where it is believed to have a homeostatic role. Reduced plasma levels of soluble RAGE (sRAGE) have been reported in patients with chronic obstructive pulmonary disease (COPD). The aim of the present study was to evaluate the association of plasma sRAGE levels with a longitudinal decline of lung function. We have also measured plasma levels of high mobility group box 1 (HMGB1), a RAGE ligand which has been associated with chronic inflammatory diseases including COPD.MethodsBaseline plasma concentrations of sRAGE and HMGB1 were measured in non-smokers (n = 32), smokers without COPD (n = 212), and smokers with COPD (n = 51), and the associations of the plasma sRAGE and HMGB1 levels with longitudinal declines of lung function during a 4-year follow-up period were analysed.ResultsThe plasma levels of sRAGE were significantly lower in smokers without COPD and in smokers with COPD, as compared to those of non-smokers. Plasma sRAGE levels positively correlated with FVC and FEV1 and inversely correlated with BMI and pack-years. Lower sRAGE levels were associated with greater declines of FEV1/FVC over 4 years in all participants. Moreover, multivariate regression analysis indicated that the baseline plasma sRAGE concentration was an independent predictor of FEV1/FVC decline in all groups. A subgroup analysis showed that decreased sRAGE levels are significantly associated with a more rapid decline of FEV1/FVC in smokers with COPD. There was no significant correlation between plasma HMGB1 levels and longitudinal decline of lung function.ConclusionsLower plasma concentrations of sRAGE were associated with greater progression of airflow limitations over time, especially in smokers with COPD, suggesting that RAGE might have a protective role in the lung.