Researchers have found that a flavouring found in tonic water is able prevent asthma, as well as limit characteristics of mice that already have the disease.

This could be a game-changer for the 300 million people worldwide that live with asthma – a disease which currently can be managed but not cured.

The researchers, from the University of Technology Sydney in Australia, found that chloroquine and quinine, substances that stimulate bitter taste buds were very successful at preventing and mitigating asthma in mice models and human cell culture.

"We do not have an effective anti-asthma therapy that targets disease progression. Our current research on taste receptors is crucial in identifying new classes of drugs that can be an effective asthma treatment option in future," said one of the researchers, Pawan Sharma.

Chloroquine and quinine are compounds used to treat malaria, and also used in tonic water to give it its bitter taste.

When inhaled, these two compounds activated the taste 2 receptor protein (TAS2R). But in doing so, they also block the allergic reaction in the lungs, and stop the asthma from occurring.

Past research has already shown that TAS2R agonists, compounds that activate the receptors, leads to relaxation in the airway of the lungs. But researchers hadn't been able to test whether it was able to prevent the inflammation of asthma.

This new research took mice models with asthma spray doses of either chloroquine or quinine.

Excitingly, the spray didn't just stop airway inflammation in the mice. It was also able to limit other characteristics of asthma, including mucus accumulation and structural changes to the airway.

The researchers confirmed these findings on human lung cells, finding that both chloroquine and quinine blocked the immune cells from reaching the airway – limiting the inflammation of the site.

The researchers still have a lot to do before we can see this treatment on the shelf, but Sharma and his team are hoping to create new bitter compounds that can be used as an asthma therapy in humans.

We're excited to see where this leads.

The research has been published in Scientific Reports.

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