PDE inhibition in obstructive lung diseases.
Pulmonary diseases such as COPD, asthma and IPF are characterized a certain degree of airway obstruction, chronic inflammation and airway remodeling. Global PDE inhibition increases cyclic nucleotide signaling and therefore provides therapeutic benefit. However, the widespread expression of PDEs in all types of lung cells causes broad inhibition of a family of isoforms and eventually also leads to unwanted side effects. Specific inhibitors of single PDE isoforms, particularly those acting specifically in particular subcellular signaling microdomains, have the potential to be more effective and specific. See text for further detail.