What lies beneath

An unassuming fish with the stripes of a grassland mammal could hold the secret to treating degenerative retinal diseases


New research that delves into how zebrafish regenerate cells in the retina could aid the development of treatments for age-related macular degeneration and retinitis pigmentosa.

American researchers at Vanderbilt University have discovered that blocking an inhibitory receptor, GABA, in zebrafish leads to increased regeneration in the retina.

Dr Thomas Greenwell, of the National Eye Institute, told OT that the research provided a new approach to inducing robust regeneration in a fish that had the natural ability to repair its own retina.

“If we can understand all of the mechanisms that make regeneration possible in a fish that naturally regenerates, then maybe some day we can do that in a mouse or human,” he highlighted.

The research, published in Stem Cell Reports, involved blinding zebrafish before injecting them with drugs that stimulate GABA production.

Researchers found that increased levels of GABA suppressed the process of regenerating the retina.

In contrast, when an enzyme that lowers GABA levels was injected in the eyes of normal zebrafish, it initiated the first stage of the regeneration process.

Dr Greenwell explained that gaining a better understanding of what happens with GABA, horizontal cells and Muller glia in the retina of mammals was an important next step.

Image credit: Oregon State University