A mouse retinal ganglion cell (green), which becomes hyperactive in degenerative vision disorders. Other retinal cell types are labeled in blue. Image credit: Shubhash Yadav, Kramer lab, University of California, Berkeley.
Researchers at the University of California, Berkeley, have found that a drug once widely used to wean alcoholics off of drinking helps to improve sight in mice with retinal degeneration.
The drug may revive sight in humans with the inherited disease retinitis pigmentosa (RP), and perhaps in other vision disorders, including age-related macular degeneration.
A group of scientists led by Richard Kramer, UC Berkeley professor of molecular and cell biology, had previously shown that a chemical — retinoic acid — is produced when light-sensing cells in the retina, called rods and cones, gradually die off. This chemical causes hyperactivity in retinal ganglion cells, which ordinarily send visual information to the brain. The hyperactivity interferes with their encoding and transfer of information, obscuring vision.
He realized, however, that the drug disulfiram — also called Antabuse — inhibits not only enzymes involved in the body’s ability to degrade alcohol, but also enzymes that make retinoic acid. In new experiments, Kramer and collaborator Michael Goard, who directs a lab at UC Santa Barbara (UCSB), discovered that treatment with disulfiram decreased the production of retinoic acid and made nearly-blind mice much better at detecting images displayed on a computer screen.
The researchers are planning to partner with ophthalmologists to conduct a clinical trial of disulfiram on patients with RP. The trial would be carried out on a small set of people with advanced, but not yet complete, retinal degeneration.