Scientists Find Protein That Triggers Diabetic Blindness Before Symptoms Appear

Diabetic retinopathy affects nearly one-third of adults with diabetes and ranks among the leading causes of vision loss in working-age adults. Current treatments only begin after symptoms like blurred vision appear, when significant irreversible damage has already occurred.

UCL researchers discovered that a protein called LRG1 triggers the earliest stages of diabetic eye damage by causing cells around tiny retinal blood vessels to constrict excessively. This squeezing action reduces oxygen delivery to the retina, starting a cascade that eventually leads to vision impairment. Importantly, this occurs much earlier than the activity of VEGF, the protein targeted by existing therapies.

In diabetic mouse models, scientists successfully blocked LRG1 activity and completely prevented early retinal damage while preserving normal eye function. This represents a paradigm shift from treating damage after it occurs to preventing it entirely. The team has already developed a drug targeting LRG1 that has shown promise in preclinical studies.

The implications are significant given that existing VEGF-targeting treatments work for only about half of patients and cannot reverse established damage. A prevention-focused approach could protect millions of people with diabetes from developing vision problems. The research was supported by major organizations including Diabetes UK, Moorfields Eye Charity, and Wellcome, lending credibility to the findings. Human clinical trials for the LRG1-targeting drug could begin in the near future, potentially offering the first truly preventive treatment for diabetic blindness.