Abstract
Purpose :
Optineurin (OPTN) E50K mutation (OPTNE50K) is known to cause normal tension glaucoma (NTG). and OPTNE50K forms aggregation in the retinal ganglion cells (RGCs), leading cell death. Therefore, we determined chemical agents that can reduce the aggregation of OPTN and have neuroprotective effect in RGCs differentiated from induced pluripotent stem cells (iPSCs) obtained from patients with NTG caused by OPTNE50K (OPTNE50K-NTG).
Methods :
RGCs were generated from iPSCs derived two healthy indivisuals (WT-iPSCs; 201B6 and 201B7 Cell line) and three patients with OPTNE50K-NTG (E50K-iPSCs) as the previous report. These RGCs derived from iPSCs were exposed by 0.01-10 µM donepezil. The efficacy of donepezil was evaluated by using Western blotting for LC3B, p62 and TANK-binding kinase 1 (TBK1). To evaluate neuroprotective effect of donepezil, we used TUJ1 and ATH5 as the marker of neurite of RGCs.
Results :
Donepezil reduced OPTN aggregation and neurite outgrowth in a concentration-dependent manner for RGCs derived from two WT-iPSCs lines and three E50K-iPSCs cell lines. In addition, donepezil decresed p62 expression and inhibited TBK1 expression in RGCs derived from E50K-iPSCs.
Conclusions :
Our study demonstrated that donepezil had the neuroprotective effect and decreased OPTN aggregation via promoting autophagic flux and decreasing TBK1 expression. These data suggest that donepezil may be a therapeutic agent for the patients with OPTNE50K-NTG because OPTNE50K impaired autophagic flux and enhanced OPTN-TBK1 interaction, leading forming OPTN aggregation.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.