Targeted gene therapy may protect against vision loss from glaucoma and diabetes, study finds

July 22 (UPI) – A new form of gene therapy could help prevent vision loss caused by diabetic retinopathy and glaucoma, according to a study published Thursday by the journal Cell.

Mice injected with genes to stimulate production of a key enzyme involved in sending images to the brain have been protected from progressive vision loss or impairment in several disease and injury models, the researchers said. researchers.

The enzyme, called CaMKII, helps strengthen retinal ganglion cells, which process visual information by sending images to the brain. They can degenerate as a result of retinal damage and retinal disease.

“Neuroprotective strategies to save vulnerable retinal ganglion cells are desperately needed for vision preservation,” study co-author Bo Chen said in a press release.

“We have discovered for the first time evidence that CaMKII … could be a desirable therapeutic target for vision preservation under conditions that damage axons and somas of retinal ganglion cells,” said Chen, associate professor of ophthalmology and neuroscience at the Icahn school. of Medicine at Mount Sinai in New York.

Glaucoma is the leading cause of irreversible visual impairment worldwide, affecting 76 million people, according to the World Health Organization.

Many people with the disease progress to blindness despite aggressive treatment to reduce the pressure in their eyes that causes it, Chen and colleagues said.

Currently, there is no cure for diseases such as glaucoma that damage the retina.

The challenge in repairing vision loss from glaucoma and other retinal diseases, such as diabetic retinopathy, is that long nerve fibers called axons do not regenerate on their own, the researchers said.

Axons allow ganglion cells in the retina to process visual information by converting light that enters the eye into a signal that is transmitted to the brain.

For this study, researchers from Mount Sinai tested the enzyme CaMKII as a therapeutic target for a wide range of injuries and diseases in mice, including optic nerve damage and glaucoma with high and normal intraocular or ocular pressure. .

In the mice used in the study, CaMKII helped preserve retinal ganglion cells in many of these injuries and illnesses, the researchers said.

Mice that had genes designed to stimulate the production of CaMKII injected directly into their eyes were protected against progressive vision loss caused by injury and disease that damaged the ganglion cells in the retina.

The gene therapy approach aims to introduce a more active type of CaMKII – with a mutated amino acid – that has been transferred to targeted retinal ganglion cells using a non-harmful virus to transport it, the researchers say.

The approach has been approved by the U.S. Food and Drug Administration and is commonly used in the growing field of gene therapy, the researchers said.

They plan to test the method in larger animal models, which could pave the way for starting clinical trials in humans.

Mount Sinai has filed patent applications for the technology through Mount Sinai Innovation Partners, the healthcare system’s commercialization arm, which is in active discussions with several companies to help advance this treatment, said the hospital.

“Our research has shown that CaMKII could indeed be a valuable therapeutic target for saving retinal ganglion cells and preserving vision in the treatment of potentially blinding diseases like glaucoma,” Chen said.

“The fact that the manipulation of CaMKII would involve a single transfer of a single gene adds to its vast potential for treating serious retinal conditions in humans,” he said.