The average mortality rate of idiopathic pulmonary fibrosis (IPF) is estimated to be 50.8 per 1,000,000 people per year and is no longer considered a rare disease. Despite this, there is no established treatment that definitely improves its outcome. Furthermore, about 10% of IPF causes acute exacerbation, with a mortality rate of approximately 80%. Thus new therapies are awaited based on new understanding of the pathogenesis of IPF.
Researchers have shown that acetylcysteine, a precursor of the major antioxidant glutathione, preserves lung function in patients with IPF better than traditional therapy. These findings suggest that an oxidant – antioxidant imbalance may contribute to the disease process in IPF.
Shunji Tajima, Niigata University, Japan, and colleagues used a bleomycin-induced pulmonary fibrosis model in mice–common animal lung fibrosis models. The authors examined edaravone, a unique potent free-radical scavenger being clinically used to treat acute brain infarction in Japan, to investigate its ability to inhibit lung injury and/or fibrosis.
This study shows that one administration of 300 mg/kg of edaravone significantly improved the survival rate, reduced lung inflammation, and attenuated reactive oxygen species and lung fibrosis. The results suggest that although edaravone might not show a therapeutic effect on chronic fibrotic lung diseases such as IPF, it may have a preventive effect in the very accelerated phases of interstitial lung diseases, such as acute exacerbation of IPF.