ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a progressive and ultimately fatal chronic interstitial lung disease characterized by a progressive decline in lung function, and current treatment options are limited. cAMP is one of the most important second messengers and plays a key role in relaxing airway smooth muscle cells and reducing inflammation. Phosphodiesterase (PDE) is a superfamily of enzymes, and PDE4 enzymes dominate 11 PDE superfamily enzymes, available in four isoforms-PDE4A, PDE4B, PDE4C and PDE4D, which selectively decompose cAMP, while PDE4 inhibitors increase cAMP levels by preventing cAMP from breaking down, thereby exerting anti-inflammatory, anti-remodeling effects and providing an attractive drug target for the treatment of IPF. This review summarizes knowledge about the association of pulmonary fibrosis with PKE4, as well as emerging preclinical studies and clinical trials regarding PDE4 inhibitors.
ABSTRACT
Current therapeutic approaches for the treatment of asthma have limitations in their ability to target all the features of the disease. Indeed, existing pharmacological asthma therapies are based on decades old strategies that were developed prior to the rapid growth in knowledge stemming from cell and molecular biology in the past decade. Thus, there is an unmet need for developing new drugs to target these features along with improved efficacy and safety. In the present review, the limitations of prevalent pharmacological asthma therapy are discussed briefly, and some explanations are suggested as to why new therapeutic targets are required to treat asthma, and finally directions for novel asthma therapies are proposed.