Un-blurring the lines in diabetes
You’re probably familiar with two types of diabetes—juvenile or type 1, which affects kids and young adults, and type 2, in older adults who are generally overweight and inactive. But the lines are less clear than they used to be. Now kids are developing type 2 diabetes, and some adult cases are actually more like a slowly progressing type 1. These fuzzy boundaries make it difficult to accurately diagnose all patients.
“Incorrect classification of diabetes is a major problem,” said Richard Pratley, M.D., adjunct professor in the Integrative Metabolism Program, director of the Florida Hospital Diabetes Institute, and senior investigator at the Florida Hospital-SBP Translational Research Institute for Metabolism and Diabetes (TRI-MD). “Some patients can go months before their need for insulin is recognized, which allows damage to the pancreas to continue and increases the likelihood that they’ll develop complications.”
To make it easier to determine which kind of diabetes a patient has, Pratley’s lab looked at an emerging class of biomarkers called microRNAs—small RNAs that regulate the translation of other RNAs into proteins. These molecules are ideal indicators of disease because they are easily measured and remain intact after samples are collected.
“We observed that each subtype of diabetes has its own pattern of microRNAs that are increased or decreased,” Pratley explained. “With further validation in more patients, these results could lead to better diagnostics that, in combination with other standard lab tests, help distinguish the various forms.”
There are three conditions in which the body doesn’t produce enough insulin:
- In type 1 diabetes, the immune system attacks the cells that make insulin—the beta cells of the pancreas.
- In type 2, the body becomes resistant to insulin, so beta cells have to work extra hard to make more and more, which eventually wears them out.
- Latent autoimmune diabetes of adults (LADA), like type 1, is caused by immune destruction of beta cells, but progresses much more slowly, and may also involve diet-related insulin resistance.
In the new study, published in Scientific Reports, Pratley’s team compared levels of microRNAs in the blood of patients with each diabetic condition. A total of eight microRNAs were significantly altered in the diabetic population compared to healthy controls.
“MicroRNA measurements alone weren’t enough to differentiate the three subtypes,” added Pratley. “But since each signature was unique, that information may improve our ability to diagnose each type of diabetic disease. Since microRNAs can be assayed noninvasively and cheaply, these tests may one day become commonplace in diabetes care.”
The paper is available online here.