Asthma — obesity connection

Bennett Shum and colleagues have found that a fatty acid binding protein called aP2, which is already known for its role in diabetes and obesity, is also present in the lung where it is crucial in controlling inflammation in asthma.

About one in ten adults and one in six children in Australia now suffer from asthma. Its incidence in Western countries increased markedly over the last 20 years and has purportedly been linked to the rise in obesity.

“There's up to three times the risk of being asthmatic if you are obese: the more obese, the greater the risk. We know that obese asthmatics who lose weight have large improvements in their asthma,” says asthma project leader Dr Michael Rolph.

Various triggers such as dust mites and pollen bring on asthma attacks, which are characterized by inflammation of the airways, a tightening of the surrounding muscles, and excess mucus production.

The scientists used a technique called gene profiling to discover novel genes that regulate airway inflammation and found very high levels of aP2 in human lung cells that had been tricked into thinking they were undergoing an asthma attack.

“We were really surprised to find aP2 in the lung”, said Shum. “So, we then looked at what would happen when we removed this gene in mouse models: mice without aP2 are protected from asthma attacks”.

“These findings suggest that blocking aP2 function is a novel approach for asthma treatment and other inflammatory lung diseases,” he added.