Research led by a team at Trinity College Dublin, with funding from Fighting Blindness, has pinpointed a potential new therapeutic target for treating retinal degeneration. The researchers have discovered that a protein called SARM1 involved in neuronal cell injury may also have a role in the progression of retinal degeneration.
In their study the team, led by Dr Sarah Doyle, first generated genetic mouse models of retinitis pigmentosa (RP) by blocking the function of the rhodopsin gene, an important gene for vision. Using this disease model they overexpressed the amounts of SARM1 that is produced in the cell. This was shown to drive and accelerate photoreceptor death in the mouse model. In contrast, when they then genetically suppressed the expression of SARM1 in the cell, there is a delay in photoreceptor death in the disease model. Furthermore, at advanced stages of disease and with the suppression of SARM1, there still seemed to be evidence of cone function.
Ultimately what the results suggests is that by deleting SARM1, you can promote rod and cone cell survival.
Explaining the significance, Dr Sarah Doyle, said: “Our research indicates that SARM1 is likely to be a key executioner in the process of retinal degeneration, because if we remove it from our experimental model system this has the effect of delaying the photoreceptor cells from dying.
“This is an important finding because the first steps involved in processing ‘light into sight’ take place in the photoreceptors. As a result, losing photoreceptors ultimately equates to losing vision. For this reason, interventions that prevent or delay photoreceptor cell death are critical to preserve sight for as long as possible in people with degenerative retinal diseases.”
This work will undoubtedly continue to grow and progress even further over the next while with the potential to advance into a study that may develop an intervention that would slow or delay vision loss in retinal degenerations.