JDRF Research

Researchers Shed Light on Cause of Blood Vessel Damage

JDRF-funded researchers in California have made an important finding about how type 1 diabetes damages blood vessels, leading to higher rates of heart disease and stroke. A better understanding of this mechanism will help scientists design therapies to stop the damage and prevent vascular disease.

Researchers at the University of California, Davis Medical Center in Sacramento reported in Diabetes that the overactive immune response in type 1 diabetes causes the vessels to become inflamed and damaged. They also identified several inflammation “biomarkers,” that give early warning of this reaction.

“This finding opens up the way for therapeutic strategies for the early prevention of a variety of complications like blindness, kidney disease, and heart disease,” said Ishwarlal Jialal, M.D., Ph.D., who led the study. “It offers hope for forestalling these complications with drugs by preventing or reducing inflammation.”

While it is well-known that people with type 1 diabetes have a higher risk of heart disease, the reasons for this have not been clear. Several studies suggested inflammation plays a role, as do white blood cells called monocytes. But until now, no one has examined these factors closely in order to establish a definite link, especially in type 1 patients who do not have symptoms of heart disease.

Although inflammation is a natural bodily response, meant to destroy, dilute or isolate both the cause of the damage and the injured tissue, chronic inflammation often makes the situation worse. When blood vessels become inflamed, they stiffen and do not dilate as needed, creating blockages that lead to heart disease and stroke. The UC Davis researchers looked at blood samples from type 1 patients who did not have heart disease, and at samples from control subjects. They found that the type 1 patients had increased levels of the inflammation biomarkers. This included higher levels of monocyte activity and several others biomarkers associated with inflammation, including C-reactive protein, which is produced by the liver.

Taken together, these findings implicate type 1 diabetes as the cause of the inflammation and subsequent vascular damage. Having biomarkers to measure should help researchers design ways to intervene and halt the process at an early stage, allowing people with type 1 diabetes to avoid cardiovascular disease down the road. Dr. Jialil says the next step in the research is to test statins—a class of cholesterol-reducing drugs shown to have anti-inflammatory effects—in people with type 1 diabetes to determine whether the drugs can safely reduce vascular complications.