Asthma can be triggered by common colds

Asthma due to common colds

05/10/2014

Certain viruses that cause common colds or other mild conditions in healthy people can lead to life-threatening respiratory distress in people with asthma. The new findings could help to prevent asthma attacks in the future.

Asthma strokes due to common cold viruses
According to a news agency dpa news agency, British researchers have discovered a mechanism that causes common cold viruses to cause asthma attacks. In experiments in the laboratory as well as in mice and humans, the scientists showed that widespread rhinoviruses in certain lung cells stimulate the production of the signal substance interleukin-25 (IL-25). "They trigger a similar signaling cascade as an allergic reaction". In the journal „Science Translational Medicine“ The team from Imperial College London writes that drugs that block IL-25 may prevent such asthma attacks.

Around 235 million asthmatics worldwide
World Health Organization (WHO) estimates that around 235 million people worldwide suffer from asthma. Differences are made between allergic and non-allergic asthma. In the non-allergic variant, asthma attacks are often caused by viral infections of the respiratory tract, predominantly rhinoviruses. These pathogens usually cause harmless conditions in healthy people, such as a cold, runny nose, or sinusitis, sometimes accompanied by headache. In asthmatics, however, such infections can sometimes trigger life-threatening respiratory distress, similar to the immune system's response to allergies.

Prevent asthma attacks
The London scientists have now studied the role of the messenger IL-25, which is involved in allergic reactions. In the lab, they infected cells of the lung epithelium of asthma patients and of healthy people with rhinoviruses. As a result, asthmatic cells produced around ten times more IL-25. Subsequent experiments with humans infected with rhinoviruses confirmed that there was more IL-25 in the nasal mucus of the asthmatic. Finally, studies in mice showed that in addition to IL-25 other signaling substances were produced, which favor inflammation. If IL-25 was blocked with an antibody, fewer such substances were formed. As the researchers said, this is one approach to prevent asthma attacks.

Chain reaction leads to seizures
According to the „world“ One of the lead investigators, Nathan Bartlett, is quoted as saying in a college statement: „Our study shows for the first time that the cells that line the airways of asthmatics are more prone to forming the small molecule IL-25, which then apparently triggers a chain reaction that leads to seizures.“ Next it says: „If we are targeting the molecule at the beginning of this cascade, perhaps we can discover a much needed new therapy to control this potentially life-threatening reaction.“

Previous therapy options
As the „world“ The study for Professor Tobias Bopp from the Mainz University Hospital explains why rhinoviruses can have such dangerous consequences for asthmatics. „That was not known yet“, so the immunologist. The blockade of IL-25 is particularly promising because this substance is at the beginning of the chain reaction. Especially for those people whose current treatment options for bronchial asthma have reached their limits, new treatment methods could help to prevent or alleviate the symptoms. (Ad)