N-acetyl-beta-hexosaminidase activity in asthma

Background: N-acetyl-beta-hexosaminidase (beta-hex) is a lysosomal hydrolase, which is selectively secreted into the extracellular space by inflammatory cells. The aim of our study was to assess the activity of beta-hex in the plasma of asthmatic patients, and to establish whether it correlates with asthma severity and airway inflammation. Methods: The study was conducted in a group of 46 asthmatic patients and 13 healthy volunteers. All study participants underwent analysis of exhaled nitric oxide and flow-volume spirometry. beta-hex activity, peripheral blood eosinophils, total serum IgE and eosinophil cationic protein were analyzed in blood samples from all asthmatic patients and healthy volunteers. Results: beta-hex activity was significantly higher in patients with severe or moderate asthma compared with healthy volunteers and was positively correlated with exhaled nitric oxide levels and serum eosinophil cationic protein in these groups of patients. There was no correlation between beta-hex activity and forced expiratory volume in 1 s, blood eosinophil count or total serum IgE in these groups of asthmatics. Conclusions: Our results suggest that beta-hex could take part in airway inflammation and remodeling in asthma. Our study is the first report in which the elevated activity of beta-hex in subjects with asthma has been observed. However, more studies are needed to establish the precise role of this enzyme in asthma in humans. Copyright (C) 2008 S. Karger AG, Basel.