Blood biomarker promises to identify diabetes before symptoms develop
Type 2 diabetes can take years to develop, and if caught early it is an entirely preventable disease. A new study suggests a particular blood biomarker could be used to identify those patients on the way to a diabetes diagnosis but yet to display symptoms of disease.
Currently, doctors performing routine health checks often measure a patient’s blood sugar levels. When those blood sugar levels are elevated but below the official threshold for type 2 diabetes, one can be diagnosed with a condition called prediabetes.
However, not all patients with prediabetes will go on to develop type 2 diabetes. In fact, only around 50 percent of those with prediabetes will progress to diabetes over a 10-year follow-up. So beyond blood-glucose tracking, how can doctors identify those patients closest to developing clinical type 2 diabetes?
One of the main pathological characteristics of diabetes is the impairment of insulin secretion from beta cells in the pancreas. As type 2 diabetes progresses, these beta cells become increasingly damaged, and by the time the disease is clearly diagnosable patients tend to have lost around half of those crucial cells.
"Identifying the transition from pre-diabetes to diabetes is complex, because the status of the affected cells, which are scattered in very small quantities in the core of an organ located under the liver, the pancreas, is impossible to assess quantitatively by non-invasive investigations,” explained Pierre Maechler, lead researcher on the new study. “We therefore opted for an alternative strategy: to find a molecule whose levels in the blood would be associated with the functional mass of these beta cells in order to indirectly detect their alteration at the pre-diabetes stage, before the appearance of any symptoms.”
So instead tracking prediabetes by simply looking at blood glucose levels, Maechler set out to find a biomarker that indicated the deterioration of pancreatic beta cells. Scanning thousand of different molecular biomarkers in a variety of mouse models of diabetes the researchers homed in on specific sugar called 1,5-anhydroglucitol.
And in this newly published study the researchers report the biomarker does indeed correlate with diabetes in humans. Across several different analyses the study demonstrated low levels of 1,5-anhydroglucitol could be associated with deficits in pancreatic beta cells.
The study first showed diabetics have lower blood levels of 1,5-anhydroglucitol compared to non-diabetics. But perhaps most interestingly the researchers confirmed the link between 1,5-anhydroglucitol and beta cells by studying changes in blood levels in patients undergoing surgery to remove parts of the pancreas.
‘‘Diabetes is a complex disease in which many metabolic changes occur in parallel,” said Maechler. “It was therefore essential to test the relevance of this marker in people who suffer a sudden loss of their beta cells but in the absence of metabolic disorders. By studying the level of 1,5-anhydroglucitol in individuals whose half of the pancreas had been surgically removed, we were able to demonstrate that 1,5-anhydroglucitol is a blood indicator of the functional quantity of pancreatic beta cells.”
These preliminary findings are certainly promising but there is more work to be done before you can go to your doctor and ask for this kind of blood test. The next step for Maechler and colleagues is to study 1,5-anhydroglucitol in a larger cohort of patients at different stages of disease.
It’s still unclear whether this biomarker will be a one-off test measuring diabetes risk or only helpful for monitoring at-risk patients by tracking changes in individual levels over time. Nevertheless, it would be extraordinarily valuable for both doctors and patients to have a simple blood test that can point to deteriorating beta cell activity before diabetic symptoms appear.
The new study was published in the Journal of Clinical Endocrinology & Metabolism.
Source: University of Geneva