Obesity has always been one of the major precursors to type 2 diabetes because of its ill effects on the body’s ability to properly use insulin. But until now, scientists haven’t been able to say with certainty just what happens in obese people to increase their insulin resistance.
Now scientists from Monash University in Melbourne, Australia, think they have an answer: a protein released by fat cells that desensitizes the liver and muscles to insulin. A large presence of the protein, called PEDF (pigment epithelium-derived factor), forces the pancreas to produce more insulin to counter the desensitization. Eventually, however, the pancreas becomes overworked, either slowing down dramatically or entirely stopping insulin production, which leads to type 2 diabetes.
Obese people, because they have more fat cells, produce more PEDF, thus increasing their chances of acquiring diabetes through a combination of insulin desensitization and stress on the pancreas.
The Australian researchers found that increasing PEDF levels in the bloodstream led to type 2 symptoms, while suppressing the protein reversed the effect and returned blood glucose levels and insulin sensitivity to normal levels.
Now that scientists have a clear link between obesity and the onset of type 2, the way is open for the development of drugs designed to control PEDF and sever that link.
The Monash team published its findings in the July 8 edition of Cell Metabolism.