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Mouse Study Reveals Treatment Window to Stabilize Vision Loss

Researchers at the Washington University Neurofibromatosis (NF) Center used a mouse model of NF1 brain tumors to discover better ways to treat vision loss.
Children with NF1 can develop a type of brain tumor (optic glioma) which affects the nerve that carries light signals from the eye to the brain. One of the major problems that these children experience from their optic gliomas is reduced vision. Unfortunately, the current treatments designed to stop optic glioma growth do not result in improved vision. For this reason, it is critical to begin to develop strategies to prevent further vision loss in these children.
Mice engineered to develop optic gliomas also experience vision loss. Joseph Toonen, PhD, a postdoctoral research fellow in Dr. David Gutmann’s laboratory, showed that tumors initiate a series of events that start with nerve injury and culminate in loss of nerve cells in the eye (retina). By determining the order of events in mice, Dr. Toonen was able to identify a time period between nerve injury and significant retinal cell death.
Next, he asked whether treating mice during this vulnerable period would lead to long lasting effects. Using a drug that restores normal Nf1 gene function in the mouse, Dr. Toonen found that tumors resumed their growth following drug removal. However, he was excited to discover that there was no further decline in retinal cell death months after treatment ended.
These results suggest that drug treatments at early stages of vision impairment might have long lasting effects on eyesight. This study was published in the journal, Neuro-Oncology.

Joseph A. Toonen, Yu Ma, David H. Gutmann. Defining the temporal course of murine neurofibromatosis-1 optic gliomagenesis reveals a therapeutic window to attenuate retinal dysfunction. Neuro Oncol 2016 now267. doi: 10.1093/neuonc/now267. PMID: 2803936