Light and drops: A new method for restoring vision
Researchers at the Institute for Bioengineering of Catalonia have developed light-activated drugs that restored visual functions in blind mice. Two of the substances tested were effective as eye drops, requiring no genetic modification or device implantation. The findings were published in the "Journal of the American Chemical Society".
Researchers in Spain, led by the Institute for Bioengineering of Catalonia, have developed new drugs activated by light and succeeded in using them to restore certain visual abilities in blind mice. Two of the substances tested worked even when administered as eye drops, without the need for genetic modification, device implantation, or special lighting. The findings were published in the scientific journal "Journal of the American Chemical Society", but the research is still in the animal testing stage and therefore it is not yet known if the method will be effective in humans.
The research focuses on diseases where the retina is damaged, including age-related macular degeneration and retinitis pigmentosa. In such conditions, the cells that capture light and allow us to see are gradually destroyed. However, other parts of the visual system within the eye may remain intact even after the loss of those cells.
To utilize the remaining system, a team led by the Institute for Bioengineering of Catalonia developed a family of substances called prosthe6. The drugs are essentially designed to fulfill part of the lost function: when light reaches the eye, the molecules change their shape and activate nerve cells in the retina. The researchers call them "molecular prostheses" because they partially replace an action previously performed by the destroyed cells.
In the first stage, the method was tested on blind zebrafish larvae, and after treatment, they regained eye movements that occur in response to visual stimuli. Later, the researchers moved on to mice that served as models for degenerative retinal diseases and tested whether the treatment allowed them to distinguish between light and dark.
Healthy mice naturally prefer dark places, while blind animals lose this preference. After receiving the drug, the tested mice began to choose dark areas again without the need for prior training. From the researchers' perspective, the behavior indicated that they were able to perceive light and use the visual information to decide where to move.
One of the most intriguing findings was that the effect appeared even under normal lighting conditions, similar to those that exist inside a building or outdoors on a cloudy day. Two substances, prosthe6-12 and prosthe6-15, stood out particularly and even worked after being administered as eye drops. This means that, at least in the experiments conducted on animals, direct injection into the eye was not always necessary.
The researchers emphasize that the drugs do not cure the disease that caused the blindness and do not bring the destroyed cells back to life. Instead, they attempt to use the surviving parts of the retina to restore a response to light. The potential advantage is that the approach does not require an electronic implant or genetic modification, and may even be suitable for different diseases without being dependent on a specific mutation.
Despite the encouraging results, this is still an early stage. The researchers are currently testing the safety of the substances and trying to extend their duration of action, with the future goal of advancing to clinical trials. If the method is subsequently proven to be safe and effective in humans, it may open a new and simpler possibility for restoring visual abilities in people suffering from advanced retinal degeneration.
