(RxWiki News) Our bodies are complex, interconnected systems. That means one health problem may be linked to another seemingly unrelated condition. Likewise, a treatment for one disease may treat a totally different disease.
Metformin, a commonly used type 2 diabetes drug, may also treat uveitis, one of the main causes of blindness around the world.
"See an eye care specialist if you have diabetes."
Uveitis is an inflammatory disease that affects the tissues beneath the outer surface of the eyeball. Lupus is one of the main causes of uveitis. About 10 to 15 percent of all cases of blindness among Americans are caused by uveitis.
The conditions is responsible for an even higher percentage of blindness around the world.
"Uveitis has various causes - the most common are infectious diseases and autoimmune disorders - but they all produce inflammation within the eye," explains Kota V. Ramana, Ph.D., of the University of Texas Medical Branch and senior author of the recent study.
"Metformin inhibits the process that causes that inflammation," he adds.
Currently, the only way to treat uveitis is the use of steroid drugs. Unfortunately, steroid therapy has some serious side effects and cannot be used for extended periods of time.
Through tests on rats and cell-cultures, Dr. Ramana and colleagues found that metformin may curb the damaging effects of uveitis.
"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," says Satish Srivastava, Ph.D., also of the University of Texas Medical Branch and one of the study's authors.
"Metformin's strong anti-inflammatory properties make this possible," he says.
Metformin was one of the earliest diabetes drugs. It is a first-line treatment for people with type 2 diabetes. Because it is already so widely used, the study's authors think it will not take long to be adopted as treatment for uveitis.
Even though this finding could lead to better prevention of blindness, it is important to keep in mind the study was done on rats. More research is needed before the drug can be used as a treatment in humans.
"I think after a few more pre-clinical studies are done, we can get this drug to patients in a shorter time than usual," says Dr. Ramana. "Its safety is already known, so all that we need to see is its efficacy in humans."
The study, which was supported by the National Institutes of Health, appears online in the journal Investigative Ophthalmology & Visual Science.