Protective Antioxidant Effects of Azadirachta indica Extract in Retina Tissue of a Diabetic Rat Model

Aims: The present study aimed to evaluate the protective antioxidant effects of ethanol leaf extract of Azadirachta indica (A.I) leaves in the retina of streptozotocin (STZ)-induced diabetic rats. Study Design: This research was an experimental, randomized, controlled in vivo study. Place and Duration of Study: Department of Biochemistry, Lead City university, Ibadan, Nigeria, between September 2024 and July 2025. Methodology: Diabetes was induced in male Wistar rats by a single intraperitoneal injection of STZ (55 mg/kg). Diabetic rats were treated daily with A.I leaf extract at doses of 200 and 400 mg/kg for 21 days. Metformin (70 mg/kg) served as a positive control, while untreated diabetic rats served as negative control, and non-diabetic rats served as normal control groups. Retinal homogenates were assayed for malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) activity, catalase (CAT) activity, and total protein using standard colorimetric/kit methods. Fasting blood glucose (FBG) was monitored. Data were analyzed by one-way ANOVA followed by Tukey's post hoc test (P 0.05), indicating comparable efficacy. Conclusion: Ethanol extract of A.I leaves exerts significant antioxidant protection in the diabetic retina by attenuating lipid peroxidation, restoring enzymatic and non-enzymatic antioxidant defenses, and preserving retinal protein integrity. These findings support its potential as an affordable natural therapeutic agent for mitigating oxidative stress in early diabetic retinopathy, warranting further mechanistic, dose-optimization, and translational studies.