Leptin plays an important role in metabolism, fertility and bone mass. But a recent study led by Columbia University Medical Center has discovered that it also regulates airway diameter. The findings go some way to explaining why obese people are more prone to asthma and indicate that weight-related asthma could be treated with drugs that increase leptin signalling.
Obesity can cause the airways to narrow, which makes asthmatic symptoms worse. However, it was discovered by the team that leptin increases airway diameter regardless of its other functions. This meant that if leptin could be signalled to be produced at a higher rate; it could make it easier for obese asthma-sufferers to breathe.
Researchers for the study first observed that weight abnormalities such as obesity and anorexia can lead to a patient developing asthma. This suggested that it might be fat cells that were affecting the function of the lungs. And leptin is a protein that is made by fat cells which then travels around the bloodstream to the brain.
In the study obese, asthmatic mice were given a substance that made their lungs more inflamed. The researchers then gave the mice drugs that would increase leptin signalling. While the inflammation stayed the same, the airways and lungs of the mice began working properly. This suggests that obese people, who suffer with inflammation, could have their asthma treated with simple drugs that improve the work-rate of the leptin already in their blood.