Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Protein involved in cystic fibrosis also plays role in emphysema, chronic lung disease

30.12.2010
A team of Johns Hopkins Children's Center researchers has discovered that a protein involved in cystic fibrosis (CF) also regulates inflammation and cell death in emphysema and may be responsible for other chronic lung diseases.

The findings, published online in the December issue of The Journal of Immunology, pave the way toward new treatments to prevent lung damage caused by infections or cigarette smoke in emphysema.

The protein, called CFTR (cystic fibrosis transmembrane conductance regulator), is already well known for its role in transporting chloride in and out of cells. In CF, the protein's chloride-carrying ability is absent due to genetic mutations, resulting in the buildup of thick sticky mucus in the lungs, which causes lung infections and breathing problems.

But the new Hopkins study indicates that CFTR is involved in immune regulation and immune response on a far wider scale. The research — conducted in mice and using lung tissue from people with and without emphysema — shows that those with lung damage from emphysema had less CFTR on the cell surface and that changes in the level of CFTR corresponded directly to disease severity. Decreases in CFTR also corresponded to increased buildup in the lung cells of a fatty molecule called ceramide, a well-known trigger of inflammation and cell death. Thus, the researchers say, by regulating ceramide's inflammation-causing activity, CFTR appears to be a watchdog for inflammation and cell death.

"Our findings suggest that CFTR is a multi-tasker protein that is not only involved in chloride transport but also in regulating cell death and inflammation by keeping in check the rampant and dangerous accumulation of ceramide," said principal investigator Neeraj Vij, Ph.D., a pulmonary researcher at Hopkins Children's and assistant professor at the Johns Hopkins University School of Medicine.

To elucidate the role played by cigarette smoking — the leading cause of emphysema — the researchers analyzed CFTR and ceramide levels in lung tissue obtained from non-smokers and from light and heavy former or current smokers. To further explore the link between cigarette smoke, CFTR and ceramide, the researchers compared lung tissue from mice with "virgin" lungs never exposed to smoke to tissue from the lungs of mice exposed to cigarette smoke for five hours a day over five days. The lungs of smoke-exposed mice had decreased CFTR expression and increased ceramide levels, thus confirming the role of cigarette smoke in lung damage. The heavier the smoking, the greater the lung damage, the lower the CFTR expression and the higher the ceramide accumulation, the researchers noted, clearly linking CFTR and ceramide levels to smoking history and disease severity.

Beyond clarifying the link between CFTR, ceramide and lung damage, the Hopkins team explained just how CFTR causes ceramide to trigger lung-damaging inflammation. Analyzing lung cells from people and mice lacking CFTR in their cell membrane under a microscope and with a technique called flow cytometry that captures changes in inflammatory and protein markers, the scientists noticed increased clustering of ceramide molecules on sections of the cell membrane called lipid rafts, known to be hot spots where inflammatory signaling proteins congregate. This clustering, the researchers said, leads to increased inflammatory signaling, greater inflammation and cell damage, but cells with normal CFTR had no such clustering. Apparently, the researchers say, when functioning properly CFTR keeps a lid on the signaling activity of inflammatory receptors by preventing them from clustering, thus warding off inflammation and lung damage.

"We anticipate that membrane CFTR and ceramide may turn out to be useful predictors of susceptibility to lung damage from smoking and infections and may be tailored for drug therapy to alter disease course," Vij said.

To further test their hypothesis, the researchers used two types of ceramide inhibitors to treat mice with lung damage caused by a bacterial infection. One of the inhibitors, FB1, successfully decreased ceramide buildup in mice with intact CFTR but failed to stop ceramide accumulation in mice with absent CFTR, as is the case in CF. However, the other type of inhibitor, AMT, curbed ceramide activity in the mice with the absent CFTR, while failing to do so in those with decreased CFTR.

"Each inhibitor appeared to be effective based on the levels of membrane CFTR and ceramide, suggesting two different therapies tailored to treat lung damage stemming from two distinct lung disorders — emphysema and CF," said co-investigator Manish Bodas, Ph.D., a post-doctoral fellow in Vij's lab at Hopkins Children's.

The research was funded by the National Institutes of Health and the Flight Attendant Medical Research Institute. Co-investigators in the study included Taehong Min and Steven Mazur, both of Hopkins.

Related:

Neeraj Vij Profile http://www.hopkinschildrens.org/Neeraj-Vij-PhD.aspx

Neeraj Vij Lab http://web.jhu.edu/vij

PubMed Publication http://www.ncbi.nlm.nih.gov/pubmed/21135173

Founded in 1912 as the children's hospital of the Johns Hopkins Medical Institutions, the Johns Hopkins Children's Center offers one of the most comprehensive pediatric medical programs in the country, with more than 92,000 patient visits and nearly 9,000 admissions each year. Hopkins Children's is consistently ranked among the top children's hospitals in the nation. Hopkins Children's is Maryland's largest children's hospital and the only state-designated Trauma Service and Burn Unit for pediatric patients. It has recognized Centers of Excellence in dozens of pediatric subspecialties, including allergy, cardiology, cystic fibrosis, gastroenterology, nephrology, neurology, neurosurgery, oncology, pulmonary, and transplant. For more information, visit www.hopkinschildrens.org

Ekaterina Pesheva | EurekAlert!
Further information:
http://www.jhmi.edu

More articles from Life Sciences:

nachricht New technique unveils 'matrix' inside tissues and tumors
29.06.2017 | University of Copenhagen The Faculty of Health and Medical Sciences

nachricht Designed proteins to treat muscular dystrophy
29.06.2017 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making Waves

Computer scientists use wave packet theory to develop realistic, detailed water wave simulations in real time. Their results will be presented at this year’s SIGGRAPH conference.

Think about the last time you were at a lake, river, or the ocean. Remember the ripples of the water, the waves crashing against the rocks, the wake following...

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Nanostructures taste the rainbow

29.06.2017 | Physics and Astronomy

New technique unveils 'matrix' inside tissues and tumors

29.06.2017 | Life Sciences

Cystic fibrosis alters the structure of mucus in airways

29.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>