The neuroprotective effect of resveratrol in the rat retinal vein occlusion model

Objective: Neurodegeneration has been shown to play a role in retinal damage associated with retinal vein occlusion. Resveratrol is a polyphenol with documented neuroprotective effects. In this study, it was planned to investigate the neuroprotective effect of resveratrol in the rat retinal vein occlusion model. Method: The eyes of Wistar albino rats were used in the study. Retinal vein occlusion was created in the right eyes of rats with laser (532nm green laser, Iridex IQ532, Iridex corp., Mountain View, CA, USA). Before the laser, 20mg/kg photosensitizing Rose-Bengal dye was applied intraperitoneally. The left eyes were not lasered, and the lasered right eyes were used as the control group. Half of the rats were given 40mg/kg resveratrol by gavage, dissolved in 3% ethanol for 14 days as a neuroprotective agent. The eyes of the rats were divided into 4 groups: In the resveratrol group, the right eyes formed the laser + resveratrol group, and the left eyes that did not receive the laser formed the resveratrol group. In the group without resveratrol, the right eyes formed the laser group, and the left eyes formed the control group. At the end of fourteen days, the rats were sacrificed and retinal isolation was performed. To assess ganglion cell survival in retinal samples, the level of Brn3a mRNA was measured by real-time PCR. Western-Blot analysis was performed to show the expression of Brn3a at the protein level. Results: Brn3a expression levels in retinal tissue samples of control, resveratrol, laser and laser+resveratrol groups were 1.062968647±0.355429593, 0.683676202±0.238218336, 1.098342833±0.322410268 and 0.954085±0.431687, respectively. P values were found as p=0.46, p=0.26 and p=0.37 in control and laser, control and laser+ resveratrol, and laser and laser+resveratrol groups, respectively. In Western-blot analyses, a band of -actin protein used as internal control was observed, but no band of Brn3a protein was observed. Conclusion: There was no significant difference in Brn3a mRNA expression level between the groups in the study. A non-significant decrease was observed in the expression level of Brn3a mRNA in the resveratrol-treated group in the eyes that did not undergo laser treatment compared to the control group. Brn3a expression could not be detected in retinal samples by Western-Blot analysis.