Abnormal blood vessel growth and the associated leakages are to factors associated with wet macular degeneration and diabetic retinopathy. These two eye diseases are the leading cause of blindness. New discoveries at the University of Utah may provide a treatment for both macular degeneration and diabetic retinopathy, as well as many other diseases.
Macular degeneration and diabetic retinopathy have been successfully treated in mice with these eye diseases by researchers at the University of Utah. These eye diseases were successfully treated by activating a protein present in blood vessels, including those in the eye. This protein known as Robo4, when activated reduced the damage previously observed in the eyes of mice and halted the formation of abnormal blood vessel growth typically attributed to wet macular degeneration and diabetic retinopathy. This protein also stabilized existing blood vessels and prevented further leakages from occurring.
This research has far reaching implications outside of its uses to treat eye disease. It also has the potential to provide insight into developing treatments for other diseases such as SARS (Sudden Acute Respiratory Syndrome) and tumors that are impacted by abnormal blood vessel growth. Serious infections such as SARS kill people when an infection destabalizes blood vessels, allowing fluids to leak into the lungs. Tumors hijack blood vessel growth to feed on nutrients and growth.
While current research did not prove that Robo4 could be used to treat diseases other than macular degeneration or diabetic retinopathy, according to Dean Y. Li, senior author of the study, this method merits further investigation for its implications in treating all diseases. “Many diseases are caused by injury or inflammation destabalizing blood vessels and causing them to leak fluid into adjacent tissues as well. We found a natural pathway – the Robo4 pathway – that counterattacks this by stabilizing blood vessels.”
The Robo4 discovery used to treat both macular degeneration and diabetic retinopathy was made by employing knockout mouse technology, which was pioneered at the University of Utah by Mario R. Capecchi, Ph.D., distinguished professor and co-chair of human genetics and recipient of the 2007 Nobel Prize in physiology or medicine.
Blood vessel growth (angiogenesis) is critical in human development and as a response to injury or disease. In earlier research, Li had shown that a family of proteins, netrins, induce blood vessel and nerve growth in mice, a discovery with important ramifications for potential therapies to help people with too few blood vessels. But when the body grows new blood vessels at the wrong time or place, these blood vessels are often unstable and weak, which causes them to leak and potentially lead to diseases such as macular degeneration and diabetic retinopathy.
Age-related Macular Degeneration is the most common cause of legal blindness in people age 65 or older. Diabetic retinopathy is the most common cause of legal blindness in working-age americans.
Li’s collaborators on the study from the University of Utah include co-first authors graduate student Christopher A. Jones and Nyall London, an M.D./Ph.D. candidate in the Department of Oncological Sciences and the Program in Human Molecular Biology and Genetics. Several other researchers from Li’s lab also contributed to the project. In addition, researchers from the University of California, San Diego, the National Heart, Lung, and Blood Institute, and Harvard Medical School were part of the study.
The study was funded largely by the National Heart, Lung, and Blood Institute and the National Eye Institute, both are part of the National Institutes of Health.
With more followup research scheduled, there may eventually be unique treatments for the eye diseases macular degeneration and diabetic retinopathy far superior to the treatments currently used to combat these eye diseases.