The Effect of Vitamin D and Melatonin on the Ocular Tissues in Streptozotocin - Induced Diabetes Model in Rats

Abstract

OBJECTIVE: The aim of the study was to investigate the effectiveness of vitamin D and melatonin on the ocular tissues in streptozotocin (STZ)-induced diabetes. MATERIALS AND METHODS: In this study. a total of 45 male Wistar rats were randomly divided into five groups as follows: 1) non-diabetic rats (control group); 2) untreated STZ-induced diabetic rats: 3) STZ-induced diabetic rats treated with vitamin D; 4) STZ-induced diabetic rats treated with melatonin; 5) STZ-induced diabetic rats treated with the combination of vitamin D and melatonin. After six weeks of treatment, all rats were sacrificed for post-mortem analyses. Retinal and corneal samples were obtained and analyzed for glial fibrillary acidic protein (GFAP) expression. Retinal and corneal thicknesses in addition to morphological changes were assessed via hematoxylin and eosin staining. RESULTS: Untreated diabetic rats revealed retinal disorganization, atrophy, increased vascularization along with more GFAP staining. However, all the treated groups exhibited more regular retinal layers and minimal GFAP staining. Additionally, treatment groups showed more uniform corneal layers with minimal GFAP staining. CONCLUSIONS: Melatonin and vitamin D could be used as an additional complementary treatment in diabetes. Developing treatment protocols involving supplementation, as well as informing patients about the potential benefits of vitamin D and melatonin could be impactful in the treatment process of diabetes.