Effects of Ethanol Extract of Propolis on Repair Optic Nerve Damage in a Rat Model for Diabetes Mellitus (Study of MDA, CRP, Caspase-3, and TGF-β Expression and Histopathological Changes on Optic Nerve Damage)

Purpose Hyperglycemia in diabetes increases oxidative stress in the body. It causes optic nerve damage and risk of glaucoma. In this study, we evaluated and analyzed the effect of propolis ethanol extract on repair of optic nerve damage in a rat model for Diabetes Mellitus. Study Design Laboratory experimental using the posttest only control group design was used in this study. Methods A total of 28 male Wistar rat were randomly divided into the following four groups namely control (K1), diabetes mellitus (K2), diabetes mellitus with propolis treatment (100 mg/kg) (P1) and diabetes mellitus with propolis treatment (200 mg/kg) (P2). Statistical analysis used ANOVA and Kruskal Wallis with a significance of p < 0.05. Results The results showed that Gunung Lawu propolis significantly reduced serum glucose levels, malondialdehyde levels and C-reactive protein levels (p<0.01). Furthermore, propolis extract significantly decreased caspase-3 expression and TGF-β expression (p<0.05) in the optic nerve. Propolis can significantly repair optic nerve damage (optic nerve necrosis, thinning of the retinal nerve fiber layer and retinal ganglion cell apoptosis (p < 0.01). Conclusion The final results showed that most of the beneficial effects of propolis were mediated by the reduction of blood glucose levels in diabetic rat.