High Levels Of Iron In The Lung Linked To Increased Asthma Severity

Discussion in 'Scientific Studies' started by md_a, Mar 18, 2020.

  1. md_a

    md_a Member

    Aug 31, 2015
    Iron build-up in the lung cells and tissues is associated with worse asthma symptoms and lower lung function, according to new research published in the European Respiratory Journal.

    The researchers say that the study, which includes data from asthma patient samples and mouse models, is the first to definitively show a relationship between iron build-up in the lung cells and tissues and the severity of asthma.

    Experimental models also showed that iron build-up in the lungs triggers immune system responses that are typical in asthma and lead to worsening of the disease. This includes effects like increased mucus secretion and scarring of the lungs, which result in narrowing of the airways and making breathing difficult.

    Iron is an essential mineral that we get from food or from supplements, which helps the body to make the red blood cells that carry oxygen around our bodies. Iron absorption is tightly regulated at the whole body, organ and cell levels to keep our iron stores balanced and maintain health. When too much iron is absorbed by cells it can lead to a build-up of iron within the cells.

    Jay Horvat, Associate Professor of Immunology and Microbiology at the University of Newcastle and Hunter Medical Research Institute, Australia, is the lead author of the study. He explained: "Our organs and tissues need iron to support oxygen flow and normal enzyme activity, but infections in the body also need iron to thrive. Because of this, our immune system has ways of hiding iron minerals within cells where infections cannot access the iron. This can result in a build-up of iron in the cells and tissues of nearby organs.

    "There is evidence that irregular iron absorption and abnormal iron levels are linked to lung disease. We know that both high and low iron levels are reported in asthma, but it is not clear whether iron build-up in the lungs contributes to disease development. We sought to build on this by investigating the link between iron and asthma, to better understand whether increased or decreased iron levels in the lung cells makes the disease worse."


    Professor Horvat explained the results: "We showed that lung function was lowest among patients with the highest levels of iron build-up in their airway cells and tissues. As lower iron levels outside of cells and higher iron levels within cells were both associated with worse lung function, we think that the immune system's role in 'hiding' iron minerals within the lung cells may be contributing to asthma severity. However, data from the patient samples is not able to confirm this relationship, and the symptoms of increased iron in lung cells were not clear."


    The analyses showed that increasing the lung cell iron levels caused inflammatory cell responses such as increased mucus secretion and scarring in the airways, which the researchers say leads to worsening of asthma. Professor Horvat explained: "In humans, mucous secretion and lung scarring narrows the airways, causing airflow obstruction and breathing difficulties. These symptoms are common in asthma and other chronic lung diseases, and our data shows that increasing iron in the lung cells and tissues led to an increase in these effects.

    "Our tests were well controlled to ensure that mice were not exposed to pathogens or other factors that might influence asthma, so we are confident that the data clearly demonstrates the link between increasing lung cell and tissue iron levels and these immune system responses."