Obesity represents a major public health problem that contributes disproportionately to the development of many comorbidities. Here it is about asthma, its severity and a reduced response to treatment. This study from the Rutgers Institute (New Jersey) suggests that obesity-related asthma is, in addition to lung inflammation, linked to narrowing of the airways. Findings presented in the American Journal of Physiology revealing that obesity "imprints" a unique and identifiable signature on airway smooth muscle cells that could lead to new targeted approaches.
The prevalence of asthma and obesity, as distinct conditions and comorbidities, has increased dramatically in recent years. Obesity is known to be a major risk factor for asthma, in part due to systemic and localized airway inflammation in people with a high body mass index. People with obesity have a higher risk of severe asthma, decreased disease control and response to treatment with corticosteroids. However, previous studies suggest that some obese patients may have a type of asthma that is not caused by airway inflammation, but by an over-reactive response to an airway smooth muscle allergen. L'
A greater muscular contraction of the airways in obese people:this research deciphers this specific mechanism of modification of the functioning of the muscles of the respiratory tract which increases the risk of asthma in obese people. The team combined human airway smooth muscle cells with histamine, a chemical produced by the immune system in response to an allergen, and carbachol, a drug that stimulates the part of the nervous system that controls the airways . Stimulating airway cells with these substances causes the cells to release calcium, as in muscle contraction. Researchers show that muscle cells from obese donors release more calcium and shrink more than cells from normal-weight donors. This suggests greater muscle contraction. Additionally, cells from obese female participants release more calcium than cells from obese male donors.
Obesity imprints its signature on the smooth muscle cells of the airways, a new marker which could therefore make it possible to better diagnose asthma in obese patients and to develop targeted therapies “against” this narrowing of the airways.
