A new large-scale genetic analysis has revealed a set of small RNA molecules, called microRNAs, in human pancreatic islet cells strongly associated with type 2 diabetes (T2D). The important discovery will guide future studies into the early detection and treatment of diabetes.
Diabetes is a chronic metabolic condition characterized by high blood glucose levels, which can lead to organ damage over the long term. The International Diabetes Federation reports that in 2021, approximately 537 million adults worldwide, or one person in 10, were living with diabetes.
Unlike type 1 diabetes – an autoimmune reaction where the body attacks pancreatic cells, resulting in little or no insulin production – T2D occurs when the pancreas either produces insufficient insulin, or the person develops insulin resistance. T2D is the most common form of the disease, affecting 90% of all diabetics.
The pancreatic islets, or islets of Langerhans, are regions in the pancreas that contain hormone-producing cells. Of the five types of islet cells present in the pancreas, the majority are beta cells. It is these cells that are responsible for producing insulin.
While it has long been known that the pancreatic islets of type 2 diabetics do not produce enough insulin to control blood glucose effectively, the molecular and cellular mechanisms underlying the condition have never been properly understood.
Previous studies have used plants or animals to investigate how microRNAs contribute to pancreatic islet functioning. But this research, partly led by scientists at the National Human Genome Research Institute (NHGRI), represents the largest analysis of microRNA expression in human pancreatic islets undertaken to date.
MicroRNAs are small, single-stranded, non-coding RNA molecules that help to regulate the type and amount of protein produced by cells. They control gene expression by binding with messenger RNA (mRNA), either marking the mRNA for destruction or subsequent translation. This process is called RNA interference (RNAi) and is an effective tool for manipulating gene expression.
“The results of this study set the stage for understanding how microRNAs fine-tune gene expression in pancreatic islets and its implications for diabetes,” said Francis Collins, MD, PhD, a senior author of the study.
The researchers found genomic variants in a region known to be associated with an increased risk of developing T2D. The insights gained from this study can be used by future researchers to better understand how T2D develops and how the condition can best be detected and treated.
“Based on this work, and building on previous studies, we hope one day to be able to identify accurate microRNA biomarkers for early detection and treatment of diabetes and improve outcomes for patients in the future,” said Henry Taylor, PhD, the first author of the study.
The new study was published in the journal of the Proceedings of the National Academy of Sciences (PNAS).
Source: National Institutes of Health
