Narrowed and hardened arteries-atherosclerosis-are a common risk associated with type 1 diabetes. Fat, cholesterol, and other substances build up to create plaque, which narrows the arteries and makes blood flow more difficult. The increased risk of blood clots often leads to heart attacks and strokes.
Now a University of Chicago study shows that transplanting pancreatic islets to type 1s significantly reduces carotid artery thickness, lowering both A1c levels and the attendant risk of atherosclerosis. (The carotid arteries are the major vessels that carry blood to and from the head.)
The transplanted islets include insulin-producing beta cells, which in type 1s have been destroyed by an autoimmune attack. By giving transplant recipients some insulin-producing ability, the islets allow them to lower their A1c levels, which researchers say leads to reduced carotid artery thickness.
The University of Chicago research team led by Kristie K. Danielson, PhD, studied 15 type 1 patients who underwent transplant surgeries. Twelve months after the surgery, the thickness of the patients’ carotid arteries decreased by an average 0.058 mm. The decrease in thickness continued in some cases for up to 50 months.
Researchers think that the re-introduction of insulin-making capability in the type 1 patients reduced inflammation by lowering blood sugar levels, leading to less stress on their arteries. However, they did not suggest that islet transplantation either directly prevented or reduced atherosclerosis.
Islet transplantation, in which still-functioning pancreatic beta cells are taken from cadavers, is one of the most assertive approaches to treating type 1 diabetes. The procedure is costly, due to its complexity, the lack of an abundant supply of donors, and the need for recipients to take immune system-suppressing drugs to avert rejection of the transplanted cells.