WASHINGTON: US researchers have discovered that a drug prescribed to millions of people with diabetes could have another important use: treating one of the world’s leading causes of blindness.
In laboratory rat and cell-culture experiments, the scientists found that metformin which is commonly used to control blood sugar levels in type 2 diabetes, also substantially reduced the effects of uveitis, an inflammation of the tissues just below the outer surface of the eyeball.
Uveitis causes 10 to 15 per cent of all cases of blindness in the United States, and is responsible for an even higher proportion of blindness globally, Xinhua news agency reported.
The only treatment available for the disorder is steroid therapy, which has serious side effects and cannot be used for long-term basis.
“Uveitis has various causes – the most common are infectious diseases and autoimmune disorders – but they all produce inflammation within the eye,” said Prof. Kota Ramana with the University of Texas Medical Branch at Galveston (UTMB), a senior author of a paper on the study published online Monday in the journal Investigative Ophthalmology & Visual Science.
“Metformin inhibits the process that causes that inflammation,” he added.
The scientists discovered metformin’s efficacy when they tested it in rats given an endotoxin that mimicked the inflammatory effects of bacterial infection. The results showed clearly that metformin was a very effective anti-uveitis agent.
“We found that the drug is therapeutic as well as preventive – if we gave our rats the drug beforehand, they didn’t develop uveitis, and if we gave it after uveitis had developed, it was therapeutic,” said UTMB professor Satish Srivastava, also an author of the paper.
— Bernama