Related Experiment Video
Updated: Aug 2, 2025
Author Spotlight: Understanding Retinal Vessel Resilience and Disease Progression
Published on: January 12, 2024
Melatonin protects retinal tissue damage in streptozotocin-induced aged rats
Adem Atacak1, Saltuk Bugra Baltaci1, Nilufer Akgun-Unal2
1Medical Faculty Department of Physiology, Selcuk University, Konya, Turkey.
Objectives:
The aim of this study was to investigate how melatonin administration affects retinal oxidative damage and retinal SIRT1 gene activation in diabetic elderly female rat model.
Methods:
16-months-old female rats were used in the study. A total of 24 rats were divided into 4 groups in equal numbers: Group 1. Control, Group 2. Control + Melatonin, Group 3. Diabetes, Group 4. Diabetes + Melatonin. In group 3 and 4 rats, diabetes was induced by intraperitoneal (IP) injection of streptozotocin. Groups 2 and 4 were given ip melatonin for 4 weeks. SIRT-1 gene expression was determined by PCR method and GSH and MDA levels by ELISA in retinal tissue samples taken from animals sacrificed under general anesthesia.
Results:
In our study, the highest retinal SIRT1 expression values were obtained in the diabetes + melatonin (G4) group. The retinal SIRT1 expression values of the diabetes group (G3) were lower than group 4 and higher than the general control (G1) and control + melatonin (G2) groups. Again in our study, the highest retinal MDA values were obtained in the diabetes group (G3). The highest retinal GSH values were obtained in the Diabetes + melatonin group (G4).
Conclusion:
The results of our study showed that melatonin supplementation has a protective effect on retinal tissue in a diabetic elderly female rat model. This protective effect of melatonin supplementation occurs by increasing both retinal antioxidant activity and retinal SIRT1 gene expression.
Insights
Melatonin supplementation protects the retina in diabetic elderly female rats by boosting antioxidant activity and SIRT1 gene expression. This study highlights melatonin
Area of Science:
- Biomedical Science
- Ophthalmology
- Gerontology
Background:
- Diabetes mellitus is a significant risk factor for ocular complications, including diabetic retinopathy.
- Oxidative stress plays a crucial role in the pathogenesis of diabetic retinal damage.
- Sirtuin 1 (SIRT1) is a key regulator of cellular metabolism and stress resistance, with potential roles in protecting against diabetic complications.
Purpose of the Study:
- To investigate the protective effects of melatonin on retinal oxidative damage in an elderly female diabetic rat model.
- To assess the impact of melatonin administration on retinal SIRT1 gene expression in this model.
Main Methods:
- Elderly female rats (16 months old) were divided into control, control + melatonin, diabetes, and diabetes + melatonin groups.
- Diabetes was induced using streptozotocin injection.
- Melatonin was administered intraperitoneally for 4 weeks.
- Retinal SIRT1 gene expression was quantified using PCR, and glutathione (GSH) and malondialdehyde (MDA) levels were measured by ELISA.
Main Results:
- Melatonin administration significantly increased retinal SIRT1 gene expression in diabetic rats compared to non-treated diabetic rats.
- Diabetic rats exhibited elevated levels of oxidative stress markers (MDA) and reduced antioxidant capacity (GSH).
- Melatonin treatment in diabetic rats led to increased retinal GSH levels and decreased MDA levels, indicating reduced oxidative damage.
Conclusions:
- Melatonin demonstrates a protective effect against retinal oxidative damage in elderly female diabetic rats.
- Melatonin enhances retinal antioxidant capacity and upregulates SIRT1 gene expression, contributing to its protective mechanism.
- These findings suggest melatonin as a potential therapeutic agent for managing diabetic retinopathy.
