A new study by researchers at Brown University suggests that gold nanoparticles, gold microscopic fragments thousands of times thinner than a human hair, could be used one day to help restore vision in people with macular degeneration and other retinal disorders.
In a study published in the magazine ACS Nano And backed by the National Health Institutes, the research team showed that nanoparticles injected into the retina can successfully stimulate the visual system and restore vision in mice with retinal disorders. The findings suggest that a new type of visual prosthesis system in which nanoparticles, used in combination with a small laser device used in a couple of glasses or glasses could help people with retinal disorders to see again.
“This is a new type of retinal prosthesis that has the potential to restore the lost vision of retinal degeneration without requiring any type of complicated surgery or genetic modification,” said Jiarui Nie, a postdoctoral researcher of the National Health Institutes who directed the research while completing his Ph.D. In Brown. “We believe that this technique could transform the treatment paradigms for retinal degenerative conditions.”
Niesto did the job while working in the Laboratory of Jonghwan Lee, an associated professor at the Brown School of Engineering and affiliated with the Faculty at the Carbon Institute of Brown Sciences, which supervised the work and served as the main author of the study.
Retinal disorders such as macular degeneration and pigmentosa retinitis affect millions of people in the United States and worldwide. These conditions damage light sensitive cells in the retina called photoreceptors: the “rods” and “cones” that turn the light into small electric pulses. These pulses stimulate other types of cells above the visual chain called bipolar and ganglionic cells, which process photoreceptors and send them to the brain.
This new approach uses nanoparticles injected directly into the retina to avoid damaged photoreceptors. When the infrared light focuses on the nanoparticles, they generate a small amount of heat that activates bipolar and ganglionic cells in the same way that photoreceptor pulses do. Because disorders such as macular degeneration affect mainly photoreceptors while leaving bipolar and ganglion cells intact, the strategy has the potential to restore lost vision.
In this new study, the research team tested the nanoparticle approach in mice retains and live mice with retinal disorders. After injecting a solution of liquid nanoparticles, the researchers used close infrared laser light to project forms on the retinas. Using a calcium signal to detect cell activity, the equipment confirmed that nanoparticles were exciting bipolar and ganglion cells in patterns coincided with the forms projected by the laser.
The experiments showed that neither the nanoparticle solution or laser stimulation caused detectable adverse side effects, as indicated by metabolic markers for inflammation and toxicity. Using probes, the researchers confirmed that the laser stimulation of the nanoparticles caused greater activity in the visual cortes of the mice, an indication that the brain transmitted and processed previously absent visual signals. That, according to researchers, is a sign that the vision had been restored at least partially, a good sign to potentially translate a technology similar to humans.
For human use, researchers imagine a system that combines nanoparticles with a laser system mounted on a pair of glasses or glasses. The cameras in the glasses would collect image of the outside world and would use them to boost the pattern of an infrared laser. The laser pulses would then stimulate the nanoparticles in people’s retinas, which allows them to see.
The approach is similar to that approved by the Food and Medicines Administration for human use a few years ago. The anterior approach combined a camera system with a small electrode matrix that was surgically implanted in the eye. The nanoparticle approach has several key advantages, according to NIE.
To start, it is much less invasive. Unlike surgery, “an intravitreous injection is one of the simplest proceedings in ophthalmology,” said Nie.
There are also functional advantages. The previous approach resolution was limited by the size of the electrode matrix: approximately 60 square pixels. Because the nanoparticle solution covers the entire retina, the new approach could cover someone’s full field of vision. And because the nanoparticles respond to infrared light almost instead of visual light, the system does not necessarily interfere with any residual vision that a person can retain.
More work should be done before the approach can be tested in a clinical environment, said Nie, but this early research suggests that it is possible.
“We show that nanoparticles can remain in the retina for months without important toxicity,” said Net on the investigation. “And we show that they can successfully stimulate the visual system. That is very encouraging for future applications.”
The research was financed by the National Eye Institute of the National Health Institutes (R01EY030569), the Scholarship Scholarship Scholarship, the Scholarship Scholarship Scholarship Scholarship and the South Korean Alchemist Projects program (RS-2024-0042269). The co -authors also include Professor Kyungsik EOM of the National University of Pusan, Professor Brown Tao Lui, as well as Brown Hafithe M. Al Ghosain, Alexander Neifert, Aaron Cherian, Gaia Marie Gerbaka and Kristine Y. Ma.