Dec 4, 2014

Saving Photoreceptors

Photoreceptor cells in the eye capture light, making vision possible. In retinal diseases such as retinitis pigmentosa and dry age-related macular degeneration, photoreceptors die, causing vision loss. Why do photoreceptors die? This question motivates many FBC-funded scientists, who are looking for ways to protect these cells and prevent them from dying.

FBC-funded scientist Dr. Phillipe Monnier is especially interested in cells that are dying through a process called apoptosis, also known as programmed cell death. Apoptosis occurs when photoreceptors are “programmed” to die from signals that are being sent from other cells. What if there was a way to block or modify these signals? Dr. Monnier’s research is focused on developing strategies to block death signals from reaching photoreceptor cells, thereby preventing their degeneration.

His strategies are centered on a particular receptor, Neogenin, which is located on the outer membrane of photoreceptor cells. Dr. Monnier’s latest breakthrough, which appears in the prestigious journal Cell Reports, shows that blocking Neogenin significantly enhances cell survival. This is fantastic news for those suffering from retinal degeneration because there is growing evidence that Neogenin is a key player in multiple cellular events occurring in eye diseases. Dr. Monnier has been involved in research in this area from the earliest basic science discoveries, and with regard to a range of conditions (glaucoma, spinal injury, stroke). We are proud to be funding his efforts to apply these findings towards therapies for retinal degenerative disease.

The eye is both an extension of and window into the brain, which makes it an ideal experimental environment for evaluating neuroprotective therapies. Indeed, these latest results suggest that focusing on Neogenin has the potential to generate a unified strategy to promote brain cell survival.

About the Study:

The paper appeared online August 21, 2014 in Cell Reports with the title: “Modifying Lipid Rafts Promotes Regeneration and Functional Recovery.” The authors include Nardos Tassew, Andrea Mothe, Alireza Shabanzadeh, Paromita Banerjee, Paulo Koeberle, Rod Bremner, Charles Tator, and Philippe Monnier. Both Dr.’s Monnier and Bremner are funded by Fighting Blindness Canada and are affiliated with the Toronto Western Research Institute and the Department of Ophthalmology at the University of Toronto.