SERPINA1 and chronic obstructive pulmonary disease: Functionally, Nqo1 can bind to SERPINA1 mRNA (which encodes the serine protease inhibitor α-1-antitrypsin, an important modulator of COPD) in its protein form, therefore maintaining the hepatic and serum levels of serine protease inhibitor α-1-antitrypsin, and inhibiting the activity of neutrophil elastase in mouse model33.