A study has revealed how poor management of blood glucose levels in people with type 1 diabetes can increase their risk of complications decades later.
In 2016, around 1.3 million adults in the United States, about 0.55% of the adult population, had type 1 diabetes, according to the Centers for Disease Control and Prevention (CDC).
Early in the course of the disease, the immune system destroys cells in the pancreas that produce insulin.
As a result, people with the condition are unable to generate enough insulin to regulate the amount of glucose, or sugar, circulating in their blood.
Over time, high levels of blood glucose, an issue called hyperglycemia, can damage tissues all over the body, including in the eyes, kidneys, nervous system, and cardiovascular system.
Even if a person regulates their blood glucose later in life, early episodes of poor glycemic control can have permanent effects, increasing the risk of developing complications.
Doctors have long recognized this phenomenon, known as metabolic memory, but its causes have been poorly understood.
Research involving animal models of diabetes had implicated epigenetic changes, which affect the activity of particular genes without altering their DNA sequences. The changes can result from disease or factors relating to a person’s environment or lifestyle.
However, direct evidence that epigenetic changes influence the risk of diabetes complications in humans has been lacking.
Now, however, scientists led by a team from the Beckman Research Institute of City of Hope, in Duarte, CA, have discovered a strong association between early episodes of poor glycemic control, epigenetic changes, and diabetic complications years later.
The research appears in the journal Nature Metabolism.
The scientists profiled a type of epigenetic modification called methylation in DNA from cells in archived blood samples. Methylation switches off genes, preventing them from producing the proteins that they encode.
The blood samples were collected some 2 decades earlier,