A new study involving Zebrafish could help researchers find new ways to fight degenerative retinal disease.
A new study involving Zebrafish could help researchers find new ways to fight degenerative retinal disease.

Researchers in the Ruiz Department of Ophthalmology & Visual Science are excited about utilizing a $1 million grant awarded by the William Stamps Farish Fund to help research how doctors can make progenitor cells in the retina regrow neurons that have been lost due to degenerative diseases that result in blindness.

Dr. John O’Brien, professor of Ophthalmology & Visual Science, said the grant will be used to hire new research staff, purchase new equipment needed for the study, and support project expenses. The project will use zebrafish as a model system. Unlike mammals, fish can grow new neurons throughout their life and can insert new neurons into the retina, which is something humans can do only during development.

“By using non-mammalian model systems that are able to regenerate neurons better, we can learn a lot about the transcriptional mechanisms that control differentiation of the progenitor cells,” O’Brien said. The team will be examining the transcriptomes of progenitor cell populations and individual progenitor cells in the retina. “We are looking for the master control genes that allow progenitor cells to form neurons.”

Dr. John O’Brien

O’Brien said the research is entering somewhat uncharted territories and will be using fish with retinal degeneration, which overproduce progenitors and continually replace lost photoreceptors. The knowledge gained from the research could translate into treating similar conditions in humans. Degenerative retinal diseases affect millions of people worldwide, with Age-Related Macular Degeneration being the leading cause of vision loss in Americans 50 and older, according to the American Optometric Association.

Researchers will be using specialized equipment designed to study visual behaviors quantitatively which in this case will be the optokinetic response, a reflex response where the eye will track moving, simple stimuli like a grating of black and white bars rotating in a cylinder around the subject.

“The eyes reflexively follow those objects and then snap back,” O’Brien said. “We can use the equipment to study the resolution of the retina, contrast sensitivity, and absolute light sensitivity.”

A second apparatus is designed for testing other types of visual behavior to allow researchers to adapt the fish to different light intensities and provide short flashes to briefly startle the fish, which allows researchers to assess whether they are blind or have recovered their vision, O’Brien said.

Projects focused on researching potential retinal regeneration have typically been side projects for O’Brien, who said he is “thrilled” to have the resources to carry out a project in earnest.

“We’re quite excited to be able to jump in and get these projects moving,” O’Brien said.