Intravitreal TRANS -Resveratrol Injection Ameliorates NMDA-Induced Optic Nerve and Retinal Injury

Abstract

Introduction Retinal and optic nerve damage in glaucoma involves excitotoxicity via N-methyl-D-aspartate (NMDA) receptors. Since, trans-resveratrol (TR) is known to provide neuroprotection, we investigated its protective effects against NMDA-induced retinal and optic nerve injury. Methods Sprague-Dawley rats were divided into 4 groups which received vehicle (PBS), NMDA and TR 0.4 or TR 4 nmol 24 hours prior to NMDA, unilaterally and intravitreally. Seven days post-injection, rats were euthanized; eyeballs were enucleated and subjected to hematoxylin and eosin (H&E) and Terminal Transferase dUTP Nick End Labeling (TUNEL) staining while optic nerves were isolated for toluidine blue staining. Results Retinal morphometry showed that ganglion cell layer (GCL) layer thickness within inner retina (IR), retinal cell count (RCC) per 100 µm length of GCL, RCC per 100 µm2 area of GCL, and RCC per 100 um 2 of inner retina were significantly higher in both TR treated groups compared to NMDA group. No differences were observed between the two dose groups. Optic nerve morphology was in accordance with the retinal morphology whereby TR treated groups have significantly lesser degenerative changes compared to NMDA. Conclusions TR protects against NMDA-induced changes in retinal and optic nerve morphology by preventing retinal cell apoptosis.