Fruit flies can help unlock mysteries of human diabetes

Researchers have developed a new technique to measure insulin levels in fruit flies, an advance that allows for the use of this insect in diabetes research.
For the first time, the tiny fruit fly can be used to study how mutations associated with the development of diabetes affect the production and secretion of the vital hormone insulin.
The new technique devised by researchers at the Stanford University School of Medicine allows scientists to measure insulin levels in the insects with extremely high sensitivity and reproducibility.
The experimental model is likely to transform the field of diabetes research by bringing the staggering power of fruit fly genetics, honed over 100 years of research, to bear on the devastating condition, researchers said.

Until now, scientists wishing to study the effect of specific mutations on insulin had to rely on the laborious, lengthy and expensive genetic engineering of laboratory mice or other mammals.
In contrast, tiny, short-lived fruit flies can be bred in dizzying combinations by the tens of thousands in just days or weeks in small flasks on a laboratory bench.

Developed by Research associate Sangbin Park, lead author of the paper, the new technique uses a chemical tag to label an insulin-like peptide called Ilp2 in fruit flies.
The tag allows researchers to use an antibody-based assay to measure insulin concentrations in the insect's blood and cells at the picomolar level - the level at which insulin concentrations are measured in humans.

Using the technique, the researchers were able to quickly identify what a mutation associated with type-2 diabetes in humans actually does: It regulates insulin secretion, but not production.
Parsing the effect of each mutation on the way the body produces, secretes and responds (or not) to insulin is critical to further understand the disease and to devise new therapeutic approaches.