How Obesity Raises Asthma Risk


Obesity is a known risk factor for asthma, and the two conditions often coexist. While this link has been thought to be due to inflammation surrounding the airways and throughout the body, a study published in the American Journal of Physiology—Lung Cellular and Molecular Physiology suggests that obesity raises asthma risk by changing how airway muscles function.

Researchers at Rutgers Institute for Translational Medicine and Science in New Brunswick, New Jersey, built on earlier studies indicating that some obese people have a type of asthma caused by hyperresponsiveness to an allergen in airway muscles, rather than airway inflammation. To test this further, the researchers combined airway muscle cells from obese and average-weight donors with histamine — which is produced by the immune system in response to allergens — and a drug called carbachol, causing a reaction that mimics muscle contraction. Carbachol stimulates the area of the nervous system that controls the airways.

They found that muscle cells from obese donors exhibited more signs of contraction than cells from donors who were not obese. Also, this reaction was greater in female donors than in male donors. The researchers concluded that it may be possible to develop new, more effective treatments for asthma that target smooth muscle cells.

Sourced from: American Journal of Physiology