Brisbane, Austrailia — Sydney-based medical research institute has discovered a link between asthma and obesity. Researchers at the Garvan Institute have found that the same fatty acid binding protein that is already known for its role in obesity and diabetes is also present in the lung.
According to Dr Michael Rolph, it is an important discovery. “AP2 is a fatty acid binding protein that is already being looked at for the treatment of obesity and diabetes,” he said. “For the first time we have found that aP2 is also active in the lung and is crucial for controlling inflammation in asthma.”
Adipocyte/macrophage fatty acid-binding protein aP2 (aP2), a protein which regulates allergic airway inflammation has been detected in human airway epithelial cells by scientists. AP2 also regulates the uptake by lipid cells of fatty acids and is associated with insulin resistance and atherosclerosis.
AP2 not only helps bring about obesity, diabetes type 2, hardening of the arteries – it also plays a vital role in allergic respiratory diseases such as asthma. The scientists mention this to be the first discovery which sees a clear link between the immune and metabolic systems.
The scientists demonstrated for the first time that aP2 is present in human epithelial cells which line the tubes that carry air from the windpipe to the bronchi (lungs). They also showed that aP2 expression is dramatically increased when the epithelial cells are stimulated with interleukin-4 and -13. This was a surprise as scientists thought aP2 was a specific marker for fat cells only.
AP2 function in mice was directly linked to infiltration into the airways of leukocytes and eosinophils. Leukocytes and eosinophils are inflammatory molecules.
This discovery emphasizes the close link between the regulation of inflammation and metabolism.
The scientists also say that a novel way of looking at asthma and other inflammatory lung disease treatments may be to block the function of aP2.