Health
Explanation for why viruses make asthma worse?
NEWS IN BRIEF — Posted April 12, 2004
Viral infections may exacerbate asthma by changing the expression of the receptors in the lung surface cells, according to a paper published in the December 2003 Journal of Biological Chemistry.
The fact that viruses can worsen asthma has been long established but never fully explained.
In order to solve this puzzle, researchers at the University of Iowa, Iowa City, exposed cell models to the respiratory syncytial virus. RSV increased the number of Toll-4 receptors on the airway cells. These receptors can act as a foothold for endotoxin found in household dust and cause additional inflammation that could constrict the airways of asthmatics.
"This could explain the viral-induced asthma exacerbations seen in people with asthma," said Martha Monick, lead author and senior research assistant in the division of pulmonary, critical care and occupational medicine in the university's Dept. of Internal Medicine.
The team plans to test the hypothesis in human subjects and animal models in the future.
Note: This item originally appeared at http://www.ama-assn.org/amednews/2004/04/12/hlbf0412.htm.
