Editorial: The Role of Arginase in Lung Disease

ABSTRACT

Nitric oxide synthases (NOSs) metabolize the amino acid Larginine to form nitric oxide (NO) and Lcitrulline. NO is involved in a broad spectrum of processes in the lungs and airways, including perfusion, ventilation, inflammation, infection and airway clearance. The activity of NOS can change in response to, for instance, inflammatory stimuli that can alter enzyme expression. In addition, NOS activity can be regulated post-transcriptionally by specific endogenous NOS inhibitors, such as asymmetric dimethylarginine (ADMA), but also by substrate limitation. The arginase isoenzymes decrease NO production by reducing the availability of Larginine for NOS [1]. There is accumulating evidence that disturbances of the balance between the Larginine metabolizing enzymes can result in both acute and chronic pathological changes. Reduced substrate availability for NOS affects the regulation of airways smooth muscle tone for instance in asthma methacholine responsiveness, and downstream products of arginase activity i.e.,Lproline and the polyamines, may contribute to lung fibrosis and airway remodeling [1-3]