The discovery of a dramatic increase of the easy-to-detect enzyme O-GlcNAcase in the red blood cells of people with diabetes and prediabetes could lead to a simple, routine test for detecting the subtle onset of the disease, before symptoms or complications occur and in time to reverse its course.
Scientists around Prof. Gerald Hart, Johns Hopkins School of Medicine, showed that the enzyme O-GlcNAcase is up to two to three times higher in people with diabetes and prediabetes than in those with no disease. It removes O-GlcNAc in red cells. O-GlcNAc is an abundant but difficult-to-detect sugar switch modifing many of the cell’s proteins to control their functions in response to nutrients and stress. Nutrients, such as glucose and lipids, increase the extent of O-GlcNAc modification of proteins affecting their activities. When the extent of O-GlcNAc attached to proteins becomes too high, as occurs in diabetes, it is harmful to the cell.