Our researcher Dr Judith Lechner is exploring innovative new ways to tackle eye damage caused by diabetes. Scientists are hopeful that stem cells could play an important role in tackling this complication in the future. Here we take a deeper dive into a recent review from Dr Lechner looking at how these shape-shifting cells could help to protect people with diabetes from life-changing vision loss.
High blood sugar levels over a long period of time can cause damage to blood vessels at the back of the eye. This complication is known as diabetic retinopathy and there isn't a cure. There are treatments, including eye injections and laser therapy, that work to slow this damage. But they only delay progression once damage has already taken hold and don’t work well for around 30% of people. So we urgently need new and better treatments.
We now know that not everyone who develops diabetic retinopathy will show significant damage to their blood vessels. Instead, some people show a loss of nerve cells in their retina.
Researchers are now exploring opportunities to address the damage by replacing the dying blood vessel or nerve cells using stem cells.
Stem cell treatments for treat diabetic retinopathy - how it works
Stem cells are unlike any other cell in our body. They have the special ability to be able to turn into many different types of cells. By replacing the dying eye cells with stem cells and restoring blood flow to the retina, researchers think it may be possible to improve vision loss caused by diabetic retinopathy.
At the moment, scientists are exploring the potential of several different types of stem cells to treat retinopathy. When stem cells are young, they’re called embryonic stem cells. At this stage they can turn into any type of cell in the body. When they get older, stem cells fully commit to only turning into one specific type of cell.
Progenitor stem cells sit somewhere in-between. They act as a repair system for the body. They can turn in to cells that maintain the blood, skin and intestines, as well as other types of special cells. Progenitor cells may be a good option for treating diabetic retinopathy since they are activated by cells being damaged or injured.
A progenitor cell called CD34+ is specific to our blood vessels. Scientists have previously found that when CD34+ cells were injected into mice with type 1 diabetes, the cells were able to locate the damage in the retina and help to prevent more damage from happening.
Improvements were also seen when progenitor cells were used to make retinal nerve cells and transplanted into rats with diabetic retinopathy. However, finding the exact approach that holds the most promise remains a big challenge.
The journey ahead
While stem cell therapy is gaining increased attention, many challenges remain before it can become a mainstream treatment to protect people living with diabetes from sight loss. We need to find out if the treatments are safe and effective, exactly when they should be started and who they would benefit most.
Clinical trials in humans, examining the potential of stem cell treatments are underway, so high-quality evidence could appear in the future. This includes an early trial to investigate the safety of using injections of CD34+ stem cells in eyes with conditions like diabetic retinopathy. So far, the researchers have yet to find any side effects or safety issues, and a larger study should follow.
With continued research, stem cell therapies could offer us a new way to slow the progression of diabetic retinopathy and protect against vision loss to help people with diabetes live healthier and happier lives.
