Acute exacerbations in COPD patients are associated with increased levels of hyaluronic acid and heparan sulfate in BAL

BACKGROUND Acute exacerbations of COPD (AECOPD) accelerate the deterioration of lung function and remain a major cause of mortality and morbidity.Glycosaminoglycans (GAGs) are essential extracellular matrix molecules that are involved in the pathophysiology of lung diseases. AIM To investigate if AECOPD is associated with differential expression of GAGs in BAL. METHODS 94 COPD patients diagnosed with either stable disease (SCOPD) (n=53) or AECOPD (n=44), undergoing diagnostic bronchoscopy were included in this study. Hyaluronic acid (HA), dermatan sulfate (DS), chondroitin sulfate (CS) and heparan sulfate (HS) were measured in BAL by ELISA. The results were correlated with lung function, smoking status, microbiology and demographic characteristics of the patients. RESULTS HA and HS were significantly elevated in BAL of patients with AECOPD as compared to SCOPD (p=0.002 and p=0.031, respectively). Furthermore, in AECOPD, there was a significant negative correlation between HA and CS with FEV1%pred (p=0.031 and p=0.025, respectively) indicating that these GAGs may contribute to airway obstruction. CONCLUSIONS AECOPD are associated with differential expression of specific GAGs such as HA, CS and DS in BAL. These molecules may be proved as potential biomarkers for AECOPD and as alternative targets for pharmacological intervention for the prevention and/or treatment of AECOPD.