Natural compounds could have the answer to treating several causes of blindness such as diabetic retinopathy and wet age-related macular degeneration.

A study involving scientists from the University of Surrey and the Eugene and Marilyn Glick Eye Institute at Indiana University School of Medicine in the USA found and tested compounds from a group of plants that could possibly be used to treat the causes of degenerative eye diseases.

This abnormal growth of new blood vessel cells in the eye is linked to a number of types of blindness, including in diabetics (proliferative diabetic retinopathy) and older adults (wet age-related macular degeneration).

In a paper published by the American Chemical Society, the University of Surrey, together with experts from Indiana University in America and Kingston University, detailed their testing of naturally occurring homoisoflavonoids found in the Hyacinthaceae plant family and their synthetic derivatives.

The team tested how well these compounds were able to stop the growth of new blood vessels and isolated several active compounds. One synthetic derivative, in particular, could be used to develop future treatments. Further work is continuing to synthesise more related compounds.

Diabetic retinopathy is caused by high blood sugar levels damaging the back of the eye - causing blindness if left untreated. It is estimated to affect 28 million people worldwide.

Wet age-related macular degeneration is one of the world's leading causes of blindness - affecting 20 million older adults worldwide.

Professor Dulcie Mulholland, Head of Department of Chemistry at the University of Surrey, said: "It goes without saying that losing your eyesight is a devastating experience. We believe that our results hint at possible future treatments for many degenerative eye conditions and it appears that nature still has many secrets to reveal."

Professor Tim Corson, Director of Basic and Translational Research at the Eugene and Marilyn Glick Eye Institute, added: "Existing therapies for these diseases must be injected into the eye, and do not work in all patients. Our findings are a first step towards therapies that might avoid these shortcomings."