Saturday, October 8, 2011

Possible new treatment for cystic fibrosis found

A novel drug could be effective in treating cystic fibrosis (CF), a study on lung cells shows. The disease is characterised by a protein defect that causes build up of mucus along the walls of the airways, eventually leading to loss of lung function and death. The newly discovered drug was chosen from a screening of 164.000 chemical compounds, to assess whether it could interact with the defective CTFR protein in epithelial cells, which form the outer lining of the airways. They found that a chemical called VX-809 was effective in restoring the functionality of CTFR up to a level that is associated with mild CF. The drug is a promising new lead to prevent the build up of mucus and give CF patients a longer, high quality life.
VX-809 corrects CTFR protein that is dysfunctional due to a specific mutation. This F508del mutation is found in two-thirds of the CF patients, and is hereditary. Humans posses two copies of the CTFR gene, and both of them need to be mutated before the CTFR protein ceases to work. Therefore, patients can inherit CF from their parents, without them suffering from the disease: if both parents have one dysfunctional copy, which they both pass on to their offspring, the child will develop CF. People with only one dysfunctional CTRF copy are called carriers.
CTFR functions by pumping chloride into the lumen of the airways. This process is dysfunctional in CF patients, causing inability of pumping across the membrane. This causes thickening of the mucus, which in turn results in breathing difficulties. This is because the cilia, the 'hair' of the epithelial wall, can no longer 'swipe' the mucus back and forth, causing it to pile up. In addition, CTFR also pumps thiocyanate across the cell membrane, which has a function in killing pathogens. Therefore, patients with CF are found to have a high incidence of lung infections. These can be treated, but not cured, by antibiotics. Lastly, the transmembrane protein also plays a role in getting iodide out of the cell and into the airwaves lumen. How the transport of chloride, thiocyanate and iodide results in pathological thickening of the mucus is not well understood.

For their experiments, the scientists isolated lung epithelial cells from CF patients carrying the F508del mutation. VX-809 restores chloride pumping up to 14 percent compared to normal epithelial cells. This may not seem like a big effect, but the corresponding physiological behaviour is associated with mild CF, found in patients that have less profound CTFR mutations and corresponding symptoms. Improving the drug could possibly crank up the efficacy even higher, eventually leading to a suitable drug to relieve CF patients of a large part of their symptoms.

Though the prevalance is not very high, CF is one of the most deadly hereditary diseases. About 30.000 people currently are CF patients in the United States. All of which will probably suffer a premature death.  Although not as much people die from CF as from cancer or heart disease, it is a horrible life-impeding disease that causes people to die way too young. A therapy to cure the disease is therefore highly required.

3 comments:

  1. It is really glad to now that as time passes by, there are treatments that are being discovered to treat fibrosis. This will really help to extend the lives of people.

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  2. I hope the therapeutic possibilities for carriers with the associated Metabolic Syndrome are going to be investigated. Being a carrier does *not* equal being "non-affected." That perception needs to be changed to reflect objective reality. There are spectra of affectation, depending on which alleles one has. I carry the common Delta deletion, with an apparently normal other allele, however I have symptoms of mild CF, and have had my whole life. I kept ear-nose-and-throat docs in business when I was between 4 and 12! If I was paid for every respiratory infection I got, I'd be a trillionaire. It sux. Not as bad as full-blown CF, I know, but still.

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  3. I am happy as Dr. Benson sensitive treatment of Cystic fibrosis (CF) touched me deeply. I have suffered from Cystic fibrosis (CF) for twenty+ years after i have gone through surgery in 2012 and I have just figured out a Dr. which help me live a safer and less painful life after my family Doctor asked me to go for a second surgery. Don't ever lose hope. I am 41 and a mother of one now , Sure, it has been challenging, and there have been many ups and downs, but I went to internet got Dr. Benson contact I contacted him and he sent me the permanent cure to it,which I used for one month. and now i am having pretty normal life now. This is not the end of the world if you having Cystic fibrosis (CF). he can help you. The medication it taste natural. And most of all, I want to tell you that you need to learn to love yourself just the way you are- you are a special person that deserves love. Never never never give up!!!!
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