Healing Process Found to Backfire in Lung Patients
A mechanism in the body which typically helps a person heal from an injury, may actually be causing patients with idiopathic pulmonary fibrosis (IPF) to get worse, researchers at the National Institute of Environmental Health Sciences (NIEHS), a part of the National Institutes of Health (NIH), and their collaborators have found.
Balintfy: The body's healing process may actually be causing lung patients to get worse, according to research at the National Institute of Environmental Health Sciences.
Garantziotis: The blood vessels are not where they're supposed to be and therefore do more harm than good.
Balintfy: Dr. Stavros Garantziotis, a staff physician at the NIEHS, studies pulmonary fibrosis which is a disease where lung tissue becomes scarred.
Garantziotis: And the lungs therefore cannot take up the oxygen, therefore the patients get more and more short of breath, need more oxygen and in extreme cases may even die.
Balintfy: Dr. Garantziotis explains that a protein in the blood, called inter-alpha-trypsin inhibitor was found to play an important role in the response to injury, in that it helps make new blood vessels.
Garantziosis: And new vessel formation is a very important part of the response to tissue injury because new vessels are needed to deliver oxygen and nutrients to the injured site and then promote the healing of the injury.
Balintfy: Researchers found through test-tube experiments and animal models that the absence of inter-alpha-trypsin inhibitor causes less vessels to be formed. Therefore they expected more would be a good thing for lung patients.
Garantziosis: However we were surprised to find out that in patients the more inter-alpha-trypsin inhibitor we found in their blood the less ability they had to take up oxygen so it seems like it caused the reverse of what we were expecting.
Balintfy: Dr. Garantziotis adds that instead of building healthy new tissue to heal the scarring in the lungs, patients with higher inter-alpha-trypsin inhibitor levels develop vessels that are far away from where they should be, pushing the blood away from the lung and bypassing the area where the body gets its oxygen, thus causing more shortness of breath. Dr. Garantziotis emphasizes that there are at least two reasons why this research is important.
Garantziosis: The first is that for the longest time people have thought that pulmonary fibrosis is a local happening, in that the lung is injured and that everybody thought that only the lung is involved in the response. What we found, interestingly, is that that inter-alpha-trypsin inhibitor is actually produced in the liver in the case of lung injury. So the response to lung injury may be a whole body affair. The second is that new vessel formation may actually be a target for treatments for pulmonary fibrosis.
Balintfy: For more information on this study, visit www.niehs.nih.gov. This is Joe Balintfy, National Institutes of Health, Bethesda, Maryland.