Preventing Blindess

Jun 17, 2013

More than 25 million Americans have diabetes, putting them at risk for eye damage that can lead to blindness. 

Often, problems occur before the disease is diagnosed, but doctors at the University of Virginia have made an exciting discovery that could protect or even restore vision.

Dr. Paul Yates is frustrated.  As a professor of ophthalmology at the University of Virginia, he often sees people with diabetes who are going blind.  They didn’t come to him early enough to prevent problems, because sight is lost at the periphery, and central vision remains.

“They say I don’t see things off to my side or up above, but until they hit the very small little center of the vision, it doesn’t register with them that there’s a problem.  I can maybe eke out a few more years of vision for them, but most are going to go blind.”

Damage to blood vessels in the eye can be traced to the loss of  special cells called pericytes.

“When these cells go away, the blood vessels die, because they are the cells that help support the blood vessels.”

The ratio of these pericytes is higher in the eye than in any other part of the body, and their loss is a serious problem, but it turns out they can be replaced with stem cells from human fat - at least in laboratory mice.  

“Starting roughly about four years ago, we decided to take these cells and inject them into the eye and see what they could do, expecting nothing, because that’s what happens in most experiments - nothing.  But what we found is that these cells actually honed into the vasculature.”

Healthy new blood vessels began to grow, raising the possibility that sight would be restored.  What’s more, by injecting the stem cells into mice with good vision, Yates and his colleagues found damage could be prevented.  Studies are needed now to see whether such a treatment could be safe and effective in humans. 

Yates figures that will take five to ten years.  In the mean time, the best hope for people with diabetes is to get regular medical care, control blood sugar levels through diet, exercise and medication.