Idebenone, an antioxidant molecule used to treat Alzheimer’s disease and other brain-damaging conditions, prevented lung damage in a mouse model of pulmonary fibrosis (PF), a study has found. The therapy also improved lung function in mice that had already developed the disease.
The study, “Idebenone has preventative and therapeutic effects on pulmonary fibrosis via preferential suppression of fibroblast activity,” was published in the journal Cell Death Discovery.
People with PF have high amounts of oxidative molecules that cause inflammation, and make cells called fibroblasts produce excessive amounts of collagen, contributing to the development of fibrosis and the accumulation of scarred (fibrotic) tissue.
Fibroblasts of PF patients, especially myofibroblasts (which are primarily involved in fibrosis), are resistant to regulatory mechanisms, such as programmed cell death. Therefore, antioxidants and compounds able to specifically eliminate lung fibroblasts are potential treatments for PF.
Ofev (nintedanib) and Esbriet (pirfenidone) are approved treatments for idiopathic PF because they slow down the loss of lung function, but they can cause adverse events, especially in the gastrointestinal tract. Therefore, safer therapies are needed.
In the study, researchers in Japan used a repository of previously approved therapies to investigate if one of them could potentially kill lung fibroblasts without affecting other cells.
This strategy, called the drug repositioning approach, consists of finding a new application for a previously approved treatment, usually reducing the time for therapies to reach patients, as the information about dosage and safety is already available.
The team found that a medication called idebenone induced cell death in lung fibroblasts without harming other types of cells, such as the epithelial cells that cover the lungs.
Idebenone is a synthetic version of coenzyme Q10 (CoQ10), an antioxidant molecule naturally produced by the body that is currently approved as an oral brain stimulant for the treatment of diseases such as Alzheimer’s.
The researchers tested the effects of idebenone in mice treated with bleomycin (a chemical compound that induces PF), and found that animals that received idebenone before receiving bleomycin did not develop fibrosis, and did not have increased levels of collagen and oxidative molecules.
CoQ10 had similar effects, which suggested that treatment with anti-inflammatory molecules could prevent the development of PF.
Treating mice with idebenone after they developed PF, but not with CoQ10, restored collagen levels, reduced the number of lung fibroblasts, and improved lung function, but it did not alter the levels of oxidative molecules.
This suggests that idebenone can not only prevent fibrosis development, but also reduce lung damage and improve lung function after the development of PF.
“These results suggest that in addition to antioxidant activity, idebenone exerts inhibitory activity on the function of lung fibroblasts, with the former activity being preventative and the latter therapeutic for bleomycin-induced fibrosis,” the researchers wrote.
Based on the results, the team said that “idebenone may be therapeutically beneficial for PF patients, as safety for use in humans has already been clinically confirmed.” It could also cause fewer adverse events than currently approved treatments.