Captopril alleviates oxidative damage in diabetic retinopathy

Area of Science:

• Biomedical Science
• Ophthalmology
• Pharmacology

Background:

• Diabetic retinopathy (DR) is a microvascular complication of diabetes, characterized by oxidative stress.
• Oxidative damage plays a critical role in the pathogenesis of DR, leading to endothelial dysfunction and vascular leakage.

Purpose of the Study:

• To investigate the protective mechanisms of captopril against oxidative stress in DR.
• To explore the relationship between captopril-mediated reduction of oxidative damage and its therapeutic effects on DR.

Main Methods:

• In vitro studies utilized human retinal microvascular endothelial cells (HRMECs) cultured in high glucose conditions.
• In vivo studies involved Sprague-Dawley rats induced with diabetes using streptozotocin.
• Biochemical assays measured total cholesterol, reactive oxygen species (ROS), nitric oxide (NO), and 3-nitrotyrosine (3-NT).
• Western blotting assessed protein expression of SREBP2, iNOS, VEGF, and eNOS.
• Histopathological analysis included Hematoxylin-eosin staining and Evans blue assay.

Main Results:

• High glucose levels significantly increased TC, ROS, NO, and 3-NT levels in both in vitro and in vivo models.
• Elevated SREBP2, iNOS, and VEGF, along with decreased eNOS expression, were observed under high glucose conditions.
• Captopril treatment reversed these detrimental changes, reducing oxidative stress markers.
• Captopril effectively alleviated diabetic retinal vascular leakage.

Conclusions:

• Captopril mitigates oxidative damage in DR by reducing ROS and NO levels, thereby decreasing peroxynitrite formation.
• These findings highlight captopril's potential as a therapeutic strategy for managing diabetic retinopathy.