Researchers from the Universities of Münster and Regensburg have discovered an emerging disease that could lead to further understanding of cystic fibrosis (CF). It could also help scientists come up with new treatment options in the future.
Cystic fibrosis is one of the most frequently inherited disorders around the world. According to the Cystic Fibrosis Association, the condition is a progressive, genetic disease that causes continuous lung infections and confines the ability to breathe over time.
The Cystic Fibrosis Foundation Patient Registry in the United States reports that more than 30,000 people are living with cystic fibrosis. Additionally, an estimated 1,000 new cases of CF are diagnosed every year.
Professor Thorsten Marquardt and his team have discovered a new disease at his lab at the University of Münster. TMEM16A, a new disease caused by defects in a different chloride channel, is thought to have implications in the treatment of CF.
In the study, the researchers were surprised to discover that not only TMEM16A but also the cystic fibrosis transmembrane conductor regulator (CFTR) gene is not functional in patients with CF. Mutations in the CFTR gene are what experts believe to be the cause of CF. The full findings of the study have been published in the Journal of Medical Genetics.
What Happens When A Person Has Cystic Fibrosis?
People with cystic fibrosis have to deal with copious amounts of thick, sticky mucus in their lungs for the rest of their lives. According to the Mayo Clinic, there is no cure for the disease. Still, there are measures given to patients to lessen the severity of symptoms, prevent complications, and improve their quality of life.
The exceptional buildup of mucus can clog the airways, which could eventually lead to severe problems with breathing and bacterial infections in the lungs. Lung infections can cause inflammation, chronic coughing, and wheezing. If left alone with no intervention, the accumulation of mucus could result in permanent lung damage, such as fibrosis, or the formation of scar tissue, and cysts in the lungs.
According to the NIH U.S. National Library of Medicine, people with CF usually have digestive complications as well. Because mucus often damages the pancreas, it affects the organ's ability to produce insulin and digestive enzymes.
Furthermore, problems with digestion can lead to diarrhea, weight loss, malnutrition, and poor growth. Adolescents and adults lacking insulin can be predisposed to developing a form of diabetes known as cystic fibrosis-related diabetes mellitus (CFRDM).
Breakthrough Discovery of a New Disease
In the disease process of cystic fibrosis, the CFTR normally arbitrates the accumulation of salt and fluids on the surface of the airways. Simply put, it is responsible for the continuous cleaning of the airways. Deficiencies or defects in the CFTR channel prevent the transport of chloride ions as well as the humidification of the respiratory tract.
Because of this, the airways of affected individuals get clogged by a thickened, viscous mucus that could completely block the airways. Moreover, patients are at the risk of suffocating due to the formation of mucus plugs in the lungs.
The researchers analyzed the cellular effects of the disorder caused by a total loss of TMEM16A function. To their surprise, the scientists discovered that not only TMEM16A but also CFTR is not operative in these patients. The authors of the study say that their discovery can improve the treatment of patients with cystic fibrosis.
Dr. Julien Park, first author, and researcher at the Marquardt lab at the Department of General Pediatrics at the University Hospital Münster, says that they found that children with TMEM16A deficiency did not display any respiratory symptoms at all. Furthermore, he says they found that the children showed no clinical symptoms of CF with their lack of TMEM16A, which also promoted the loss of CFTR function.
Correspondingly, Professor Karl Kunzelmann's team found similar results in a mouse model, wherein knockouts of CFTR and TMEM16A did not develop lung disease. When analyzed all together, the researchers question whether inhibition of TMEM16A through pharmacological means could improve the respiratory symptoms of patients with CF. In conclusion, Kunzelmann says that their next step is to plan for clinical trials to assess cystic fibrosis treatment with TMEM16A inhibitors.
