Smoking reduces surfactant protein D and phospholipids in patients with and without chronic obstructive pulmonary disease.

ABSTRACT: Pulmonary surfactant D (SP-D) has important regulatory functions for innate immunity and has been implicated as a biomarker for chronic obstructive pulmonary disease (COPD). We hypothesized that COPD patients would have reduced bronchoalveolar lavage (BAL) fluid SP-D levels compared to healthy smoking and non-smoking controls.BAL SP-D and phospholipids were quantified and corrected for dilution in 110 subjects (65 healthy never smokers, 23 smokers with normal spirometry, and 22 smokers with COPD).BAL SP-D was highest in never smokers (mean 51.9 ?g/mL ± 7.1 ?g/mL standard error) compared to both smokers with normal spirometry (16.0 ?g/mL ± 11.8 ?g/mL) and subjects with COPD (19.1 ?g/mL ± 12.9 ?g/mL; P < 0.0001). Among smokers with COPD, BAL SP-D correlated significantly with FEV1% predicted (R = 0.43; P < 0.05); however, the strongest predictor of BAL SP-D was smoking status. BAL SP-D levels were lowest in current smokers (12.8 ?g/mL ± 11.0 ?g/mL), intermediate in former smokers (25.2 ?g/mL ± 14.2 ?g/mL; P < 0.008), and highest in never smokers. BAL phospholipids were also lowest in current smokers (6.5 nmol ± 1.5 nmol), intermediate in former smokers (13.1 nmol ± 2.1 nmol), and highest in never smokers (14.8 nmol ± 1.1 nmol; P < 0.0001).These data suggest that smokers, and especially current smokers, exhibit significantly reduced BAL SP-D and phospholipids compared to nonsmokers. Our findings may help better explain the mechanism that leads to the rapid progression of disease and increased incidence of infection in smokers.

SUBMITTER: More JM 

PROVIDER: S-EPMC2987951 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature