Genes linked to asthma more active in people who are obese, study finds

People who are obese might be able to reduce or eliminate symptoms of asthma simply by shedding pounds, new research suggests.

Researchers at the University of Buffalo found the behavior of asthma-linked genes could change when obese patients received gastric bypass surgery and, consequently, lost a lot of weight.

Chronic inflammation

The study found four genes that are associated with chronic inflammation in asthma were more active in obese people – with the highest levels of activity found in the morbidly obese. This increased gene expression can cause white blood cells to produce more inflammatory factors that contribute to allergic information, stated a press release on the study.

Researchers also found higher concentrations of two asthma-related compounds in obese people: MMP-9, which is associated with inflammation, and nitric oxide metabolites (NOM), which are indicators of oxidative stress.

Weight loss improved inflammation

After patients in the study received gastric bypass surgery, the expression of six asthma-related genes dropped along with MMP-9 and NOM levels. Diabetes symptoms also improved.

The research is important because it establishes the connection between obesity and asthma that is based on biological mechanisms, researchers noted.

"Ours is the first study to provide a mechanistic link between obesity and asthma through biological/immunological mechanisms," said author Paresh Dandona, M.D., Ph.D., SUNY Distinguished Professor and Chief of Endocrinology, Diabetes and Metabolism at the University at Buffalo, said in a statement. "There has been, until now, no biological, mechanistic explanation other than the fact that obesity may raise the diaphragm and thus reduce lung volumes."

The next step will be to conduct clinical studies on how weight loss affects asthma in obese patients, Dandona said.

Source: University of Buffalo