Scientists have found a new way to regenerate damaged optic nerve cells taken from mice and raised in a dish. This exciting development could lead to potential eye disease treatments in the future.
Damage to fully developed nerve cells causes irreversible and life-changing consequences, because once the nerve fibers mature, they lose their ability to regenerate after injury or disease. . The new experiments show how to activate part of the nerve cell regeneration engine, a protein called convex, that can stimulate the nerves in the eye to regrow after an injury.
With more research, this achievement is a step towards future glaucoma treatments, a group of eye conditions that cause vision loss by damaging the optic nerve (the eye link to the brain).
Ophthalmologist Keith Martin from the University of Melbourne in Australia said: “What we see is the strongest regeneration of any technique we have used before.
“Before it seemed we could not regenerate the optic nerve, but this research shows the potential of gene therapy to do this.”;
We have seen similar efforts to restore vision in mice and some promising results in the past.
In 2016, scientists were able to regrow a small portion of retinal ganglion cells in adult mice by turning on the inactive growth switch and showing these new neurons in the back of the eye as well. reconnect with the right brain.
And before that, a 2012 study also partially restored ‘simple’ vision to adult rats after regenerating nerves along the entire length of the visual path.
This latest research is still in its early stages and has focused on understanding exactly how the convex, a scaffold molecule found in sprouting neurons, aids cell growth. planing.
It’s always good to have a few options as there is no guarantee that the promising results in mouse studies will translate into safe and effective treatments for humans.
In this study, the scientists stimulated the nerve cells of the eye to produce more protrusions, to see if this could help protect the cells from damage and even repair after injury. or not.
First, in optical neurons grown in a dish, researchers showed that increasing the protrusion production stimulates the regeneration of nerve cells that were cut by the laser. . Their slender axons regenerate in longer distances and in less time than untreated cells.
Above: A regeneration and the axon do not regenerate for more than 14 hours after laser cutting. The red arrow at 0 hours after the injury indicates the point of injury; The white arrows line the path of the regenerative axon.
Next, the adult mice were given gene therapy – an injection in the eye – that carried instructions for the nerve cells to increase protrusion production. It sounds painful, but the procedure can actually be done safely in humans (injections, that is, not gene therapy).
Several weeks and once with a subsequent optic nerve injury, these mice had more surviving neurons in the retina than the control group.
In a final experiment, the scientists used the entire retina of the rats removed two weeks after giving them convex enhancement, to see if this treatment could suppress cells. Neurons die in the first place or not.
Three days later, the researchers found that the convex stimulus “completely protects the nerve, with these retinas not being lost. [retinal] Researchers write in their articles. Normally, about half of the retinal nerve cells removed in this way die within a few days.
“Our strategy is based on using gene therapy – a method already clinically used – to bring protrusions into the eye,” said Veselina Petrova, a neuroscience student at Cambridge University. know.
“It is likely that our treatment could be further developed as a way to protect retinal nerve cells from death, as well as stimulate their axons to regrow.”
It’s important to note that we are far from restoring a person’s vision: Cell regeneration in a dish is great, but we don’t know from these experiments if the rats are over-convex than to restore its eyesight or not.
One of the next steps will be to look at whether the protrusion has a similar protective effect in cultured human retinal cells.
The scientists who published this work also plan to study whether the same technique could be used to repair nerve cells damaged after a spinal cord injury.
“Treatments defined this way often show great promise in the damaged spinal cord,” said Petrova. “It could be a protruding enhancer or activated substance that could be used to enhance regeneration in an injured spinal cord.”
Research is published in Scientific reports.