Hsa_circ_0004776 regulates the retina neovascularization in progression of diabetic retinopathy via hsa-miR-382-5p/BDNF axis.

The aim of this work was to identify the regulatory function of hsa_circ_0004776 in the progression of diabetic retinopathy (DR). The direct interactions between hsa_circ_0004776 and hsa-miR-382-5p and between hsa-miR-382-5p and BDNF, were confirmed via dual-luciferase reporter assays. Quantitative Real-Time PCR analysis indicated that hsa_circ_0004776 was highly expressed in aqueous humour samples of DR patients and human retinal microvascular epithelial cells (hRECs) under a high-glucose environment, whereas hsa-miR-382-5p showed the opposite trend. Overexpressed hsa_circ_0004776 significantly enhanced DNA synthesis, proliferation, migration, and tube formation in hRECs in hyperglycaemia, while hsa-miR-382-5p mimics reversed these changes. Additionally, in a streptozotocin-induced Sprague-Dawley rat model of DR, vitreous microinjection of rno-miR-382-5p agomir reversed the pathologic features in the progression of DR, including retinal vascular leakage, capillary decellularization, loss of pericytes, fibrosis, and gliosis. Our results indicated that under hyperglycaemic conditions, hsa_circ_0004776 influences the progression of DR via hsa-miR-382-5p and thus represents a potential therapeutic target.