PJ34 Protects Photoreceptors from Cell Death by Inhibiting PARP-1 Induced Parthanatos after Experimental Retinal Detachment.

Our previous study discoveredreactive oxygen species (ROS) and apoptosis inducing factor (AIF) increased after retinal detachment. Parthanatos is a cell death form involving ROS and AIF, which is induced by poly (ADP-ribose) polymerase-1 (PARP-1). Therefore, we investigated whether PJ34 (a PARP-1 inhibitor) could inhibit parthanatos and protect the photoreceptors from cell death after retinal detachment (RD). Experimental retinal detachment modelswere created in Sprague-Dawley rats by subretinal injection of sodium hyaluronate.PJ34 orDMSO were introduced into subretinal space at RD induction, respectively. The structure of retinas and the morphology of photoreceptors were observed by hematoxylin eosin (H&E) staining and transmission electron microscope (TEM). Parthanatos related proteins (PARP-1, PAR,AIF) were detected by Western blot. The vision-dependent behavior of rat was tested by Morris water maze. H&E staining and TEM results indicated that the structure and outer nuclear layer (ONL) thickness of retinas were preserved, and the photoreceptors death decreasedwith PJ34 treatment. Western blot showed that the expression of PARP-1, PAR and AIF were decreased withPJ34 treatment. In addition, administration of PJ34 also improved the vision-dependent behavior of rat. These findings suggested that PJ34 is a potential therapeutic agent that attenuated photoreceptor parthanatos death in retinal detachment through inhibition of PARP-1/AIF pathway.