Angiotensin-blocking drugs may hold promise for diabetic retinopathy

MELBOURNE, Australia — Clinical trials of an angiotensin-blocking drug for treating diabetic retinopathy are now under way, after research here found promise in animal studies of the drug.

Jennifer Wilkinson-Berka, MD, and colleagues here at the University of Melbourne noticed the drug’s effectiveness for diabetic retinopathy and diabetic nephropathy while using it to treat high blood pressure in patients with diabetes. They found that the chemical system in the body that caused high blood pressure in diabetic patients was also involved in kidney and retina damage. The system, dubbed the Renin-Angiotensin System (RAS), is triggered by high blood glucose levels, and its end product is a protein called angiotensin that causes cells to grow.

“Diabetic patients now take these drugs to treat kidney damage, but nobody had thought to look if RAS also operated in the eye,” said Dr. Wilkinson-Berka.

Using a rat model with an enhanced RAS, the researchers discovered RAS was present and active in the eye when blood glucose reached high levels.

“We are aiming for a non-destructive, preventative treatment that doesn't involve destroying retina,” said Dr. Wilkinson-Berka.

Both the U.S.-based Juvenile Diabetes Research Foundation and Australia's National Health and Medical Research Council are financially supporting the research. Total funding from the two groups is $4.7 million over the course of 5 years.