Repurposed L-DOPA for the treatment of diabetic retinopathy.
- Shows improved overall retinal and visual function.
- Delays progression of disease.
- L-DOPA is an FDA approved drug.
It is estimated that nearly one in ten people globally will have some form of diabetes by 2035 and diabetic retinopathy affects a third of diagnosed diabetics. Diabetic retinopathy occurs when diabetes weakens tiny blood vessels in the eyes which can burst and cause cloudy vision, scar tissue in the eye, and ultimately vision loss. There is no cure but if detected early, laser treatment can be used to prevent vision loss and anti-VEGF (vascular endothelial growth factor) or anti-inflammatory steroids are injected directly into the eye in order to help shrink blood vessels. Treatments that improve retinal and visual function with low side effects and without surgical intervention could help treat those that may have been diagnosed later and have already experienced vision impairments.
In the past, diabetic retinopathy has been primarily considered a vascular disorder due to its association with structural defects of blood vessels in the retina. Although clinical research has emphasized this vascular symptom, retinal neuronal dysfunction occurs prior to the detection of vascular lesions. Specifically, dopamine in the retina modulates visual function. Levels of dopamine are reduced in the retinas of diabetic mice and a key metabolite, DOPAC, in the dopamine pathway decreases in retinal neurons after diabetes. Emory researchers have found that while diabetes reduced retinal dopamine levels, treatment of L-DOPA improved overall retinal and visual function in diabetic mice. In addition, dopamine restoration delayed diabetes-induced visual dysfunction. L-DOPA treatment may serve as a potential repurposed therapeutic for early-stage diabetic retinopathy.
- In vivo study completed in a rodent model of type-1 diabetes.
- Clinical study in progress.
Publication: Aung et al., 2014. J Neurosci. 34: 726-736.