The role of PPARs in pulmonary diseases

Pulmonary inflammatory diseases, such as acute lung injury(ALI), asthma, chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF), are major global health problems. Despite the existence of a lot of therapeutic agents such as anticholinergics, theophylline, glucocorticoids, β2 adrenergic receptor agonist and anti-cytokine therapy, the outcome of these diseases is still poor. One class of key medicines for such diseases, glucocorticoids, show significant side effects and toxicities, which is also less effective in ALI and COPD. Therefore, there is an urgent requirement to look for new stragtegy and new medicine to manage these diseases. Peroxisome proliferator-activated receptors (PPARs) has broad effects like anti-inflammation, immuno-modulation and inhibition of cell proliferation, suggesting that PPAR agonists may have a potential value in treating these diseases. This review summarizes the recent studies of protective functions of PPAR signaling pathway in such diseases, in order to provide theoretical basis for clinical treatment of these diseases.