Doctors in Germany working on mice say a drug commonly used for depression is a promising candidate as a new treatment for cystic fibrosis.
Amitriptyline -- commercialised under such names as Elavil, Endep and Vanatrip -- reduces levels in the lung of a fatty molecule called ceramide, they found.
A buildup of ceramide leads to the death of lung cells and inflammation, causing bacterial infection, which is the leading cause of mortality among people with cystic fibrosis, they discovered.
The study, which appears on Sunday in the journal Nature Medicine, was conducted on cells taken from 18 adult volunteers with cystic fibrosis and on mice that had been genetically modified to reproduce the symptoms of the disease.
Its authors, led by Erich Gulbins of the University of Duisburg-Essen in western Germany, say amitriptyline could become "a new and important strategy" to curb infection among people with cystic fibrosis.
They stress, though, that the drug would have to be carefully dosed in order not to eliminate ceramide totally as this lipid, in lower concentrations, also plays an important role in cell maintenance.
Cystic fibrosis is caused by mutations in a gene called CFTR, which causes a thick layer of mucus to line the lungs. Around 80,000 people in Europe and North America are estimated to have the disease.