Evaluation of the Effect of Melatonin Treatment on Telomere Length of the Retinal Pigment Epithelium in Streptozotocin-Induced Diabetic Rat Model

Abstract

Abstract Objectives: We aimed to investigate the effect of diabetic retinopathy and melatonin treatment on the relative telomer lengths (RTL) in retinal pigment epithelium (RPE) cells in a streptozotocin-induced diabetic rat model. Background: TL can be used to evaluate diabetes mellitus, its complications, and the effectiveness of its treatment. However, TL assessment has not been performed in retinal cells in a diabetic retinopathy model until now. Methods: Forty Sprague-Dawley male rats were randomly divided into four groups. The experimental groups were: Control Group (C): non- diabetic rats; Diabetes Mellitus Group (DM): rats induced to diabetes without treatment; Melatonin and Diabetes Mellitus Group (Mel +DM): rats induced to diabetes and after confirmation, treated with melatonin; Melatonin Group (Mel): rats were not induced to diabetes, treated with melatonin. Diabetes was induced by intraperitoneal administration of streptozotocin solution after 12 h food fasting. For eight weeks after the diabetes was induced, melatonin was administered via subcutaneous injection at a dose of 10 mg / kg. RTLs were measured by qPCR method with modifications. The comparison of averaged data among groups was performed using least significant difference (LSD) and Kruskal – Wallis Test and One way ANOVA test. Results: RTL was significantly similar in control and melatonin group. RTL was thinnest in DM group, in addition melatonin treatment significantly prevented the RTL shortening in DM + Mel group (p=0.031). Conclusion: We demonstrated that diabetic retinopathy led to the shortening of RTL in RPE cells in rats and melatonin treatment prevents this shortening.