Cystic fibrosis: New compounds display strong therapeutic potential

September 30, 2013

Cystic fibrosis is a lethal genetic disorder that in France affects one child per 4,500 births. An international team led by scientists at the Institut Fédératif de Recherche Necker-Enfants Malades (CNRS/Inserm/Université Paris Descartes), led by Aleksander Edelman, has recently discovered two new compounds that could be used to treat patients carrying the most common mutation. By means of virtual screening and experiments on mice and human cells in culture, the scientists were able to screen 200,000 compounds and selected two that allowed the causal mutated protein to express itself and fulfill its function.

These findings were recently published online in EMBO Molecular Medicine.

Cystic fibrosis is a genetic disorder that affects the epithelia of numerous organs, and particularly those in the lungs, pancreas and intestine. In the lungs, this takes the form of insufficient epithelial hydration, resulting in excess mucus in the bronchi. This mucus retains pathogenic agents and favors the onset of chronic infections and inflammatory conditions that are ultimately fatal to the sufferer.

The disease is caused by mutations in the gene coding for a protein called CFTR ( transmembrane conductance regulator). This protein, which is essential to ensure the passage of water through an epithelium, is an ion channel that allows chloride ions to pass through cell membranes. To date, about 2,000 gene mutations that cause the disease have been determined, but 70% of cases of cystic fibrosis are due to a single mutation called ?F508. And it is this mutation that is targeted by the recently-discovered .

The scientists used computer techniques to screen 200,000 compounds, looking for those that might interact with a specific zone in the abnormal protein, and found about a dozen potentially active molecules. Using these 12 compounds, they then performed in-vitro tests on human cell cultures and in-vivo experiments on mice showing this mutation. They were thus able to observe that two of these compounds allowed the mutated delta-F508-CFTR protein to be trafficked to the membrane and fulfill its role.

One of the highlights of this work was that the scientists were able to describe the mechanism of action of these two compounds. In itself, and despite its mutation, the delta-F508-CFTR protein may satisfactorily fulfill its function. The problem is that once it is synthesized, it is recognized as being abnormal by keratin 8, another protein which favors its degradation, thus preventing delta-F508-CFTR from reaching the cell membrane. The compounds discovered by the scientists inhibit the interaction between keratin 8 and delta-F508-CFTR so that the can be deployed appropriately and fulfill its role as an ion channel. The scientists think that for potential therapeutic purposes, the two molecules they have discovered could be associated with "potentiating" compounds that would enhance the activity of delta-F508-CFTR.

The scientists now want to determine whether these two compounds do indeed cause a reduction in the susceptibility to infection of cystic fibrosis mice models. They also hope to start clinical trials in cystic fibrosis patients in the coming years.

Explore further: An 'unconventional' path to correcting cystic fibrosis

More information: Discovery of novel potent delta-F508-CFTR correctors that target the nucleotide binding domain, Norbert Odolczyk, Janine Fritsch, Caroline Norez, Nathalie Servel, Melanie Faria da Cunha, Sara Bitam, Anna Kupniewska, Ludovic Wiszniewski, Julien Colas, Krzysztof Tarnowski, Danielle Tondelier, Ariel Roldan, Emilie L. Saussereau, Patricia Melin-Heschel, Grzegorz Wieczorek1, Gergely Lukacs, Michal Dadlez, Grazyna Faure, Harald Herrmann, Mario Ollero, Frédéric Becq, Piotr Zielenkiewicz, Aleksander Edelman, EMBO : DOI: 10.1002/emmm.201302699

Related Stories

An 'unconventional' path to correcting cystic fibrosis

September 1, 2011

Researchers have identified an unconventional path that may correct the defect underlying cystic fibrosis, according to a report in the September 2nd issue of the journal Cell. This new treatment dramatically extends the ...

Gene network restores CF protein function

August 1, 2012

Researchers at the University of Iowa Carver College of Medicine have discovered a genetic process that can restore function to a defective protein, which is the most common cause of cystic fibrosis (CF).

New avenue for improved treatment of cystic fibrosis

July 9, 2013

(Medical Xpress)—Cystic fibrosis is caused by a mutation in the gene that encodes a particular protein, known as the cystic fibrosis transmembrane conductance regulator (or CFTR). Although this discovery was made 25 years ...

Potential new drug target for cystic fibrosis

September 13, 2013

Scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg and Regensburg University, both in Germany, and the University of Lisboa, in Portugal, have discovered a promising potential drug target for cystic ...

Recommended for you

Flu study, on hold, yields new vaccine technology

September 2, 2015

Vaccines to protect against an avian influenza pandemic as well as seasonal flu may be mass produced more quickly and efficiently using technology described today by researchers at the University of Wisconsin-Madison in the ...

We've all got a blind spot, but it can be shrunk

August 31, 2015

You've probably never noticed, but the human eye includes an unavoidable blind spot. That's because the optic nerve that sends visual signals to the brain must pass through the retina, which creates a hole in that light-sensitive ...

Biologists identify mechanisms of embryonic wound repair

August 31, 2015

It's like something out of a science-fiction movie - time-lapse photography showing how wounds in embryos of fruit flies heal themselves. The images are not only real; they shed light on ways to improve wound recovery in ...

New 'Tissue Velcro' could help repair damaged hearts

August 28, 2015

Engineers at the University of Toronto just made assembling functional heart tissue as easy as fastening your shoes. The team has created a biocompatible scaffold that allows sheets of beating heart cells to snap together ...

Fertilization discovery: Do sperm wield tiny harpoons?

August 26, 2015

Could the sperm harpoon the egg to facilitate fertilization? That's the intriguing possibility raised by the University of Virginia School of Medicine's discovery that a protein within the head of the sperm forms spiky filaments, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.