Researchers identify mechanism behind diabetic complications

Blood vessel problems are among the most common complications for individuals with type 1 diabetes and type 2 diabetes. However, a team of researchers from Washington University in St. Louis recently discovered the underlying cause of these complications, which may enable them to produce improved medications that help individuals avoid the problems.

It has long been known that persistently high blood sugar levels can damage the body's veins and arteries. This is the cause of some of the most common diabetic complications, including amputations, heart disease, stroke and retinopathy. However, it was less clear why the body could not heal this damage.

The researchers found through animal studies that this reduced healing ability stems from a complex interaction of enzymes. They reported in the Journal of Biological Chemistry that nitric oxide synthase plays an important role in allowing certain cells in the circulatory system to regenerate. In order to do this, it needs a lipid produced by the enzyme fatty acid synthase.

Previous studies have shown that diabetics have low levels of fatty acid synthase. This is generally caused by a lack of insulin. Without this enzyme, the body cannot produce the lipid that nitric oxide synthase needs to function properly. When nitric oxide synthase is not working, blood vessels cannot repair themselves.

"In animals that don't have fatty acid synthase and normal nitric oxide synthase in endothelial cells, we saw a lot of leaky blood vessels," said Clay Semenkovich, who led the study. "The mice also were more susceptible to the consequences of infection, and they couldn't repair damage that occurred - problems that also tend to be common in people with diabetes."

The researchers added that drugs that promote the production of fatty acid synthase might help individuals with type 1 or type 2 diabetes avoid potentially fatal complications.