Scientists Restore Vision of Blind Mice, Could Aid in the Development of Human Vision Loss Treatments
A group of U.S. scientists has restored the vision of blind mice in a first-of-its-kind scientific experiment.
Medical experts have long believed that a damaged optic nerve, which connects the eyes to the brain, could lead to permanent vision loss.
However, during an experiment on blind mice, scientists have found out a way to re-establish the connection between the eyes and the brain.
"For the longest time people in the field wondered if neurons could regenerate and form the correct patterns to connect to the brain, and we found that they did," Andrew Huberman, associate professor of neurobiology at Stanford University and author of the study, said in a report in Time.com.
In the study, which was published in Nature Neuroscience, the researchers experimented on mice that had damaged optic nerves. The mice were intended to serve as models in their study about glaucoma, which is the second-leading cause of blindness in the world after cataracts.
"In humans we have about 1 million cells connecting each eye to the brain," Huberman said in an interview with Live Science.
Once the optic nerves are damaged, the long, thread-like arms of the nerve cells - called axons - connecting the eye to the brain start to wither, severing any connection to the brain and resulting in blindness.
Huberman and his team found that through gene therapy, visual stimulation of the nerve and nerve-growing chemicals, the axons can regrow and make their way to their specific destinations in the brain.
"It means that neurons remember the way home; they never forget," Huberman said.
Experiments on mice included gene therapy, which involved boosting the mTOR pathway in the brain, and intense daily exposure to images of moving black-and-white grid or a combination of both.
However, the scientists said that their work in mice may not have immediate implications for humans yet, but the research points them to new directions.
"[The work] is strongly informative toward developing new tools for treating vision loss in humans," Huberman said.