Diabetic retinopathy (DR) is a microvascular complication of diabetes. Hyperglycemic/hypoxic microenvironment concurs to aberrant angiogenesis characterizing the pathology and activates many downstream target genes including inflammatory cytokines and vasoactive peptides, such as interleukin-1Î² (IL-1Î²) and vascular endothelial growth factor (VEGF). It has been largely demonstrated that pituitary adenylate cyclase-activating peptide (PACAP) plays a protective effect in DR. In the present study, we investigated the role of PACAP to protect retinal tissue through IL-1Î² and VEGF expression. Diabetes was induced in rats by streptozotocin (STZ) injection, and one week later a single intravitreal injection of 100 Î¼M PACAP was administrated. Analyses of IL-1Î² and VEGF levels were performed three weeks after diabetes induction. The results demonstrated that a single intraocular administration of PACAP significantly reduced the expression of IL-1Î² in diabetic animals. Moreover, it affects VEGF and its receptors (VEGFRs) levels and interferes with their retinal layers distribution as showed by confocal microscopy analysis. In particular, PACAP treatment downregulates VEGF and VEGFRs that are increasingly expressed in STZ-treated animals as compared to controls. These results indicate that PACAP plays an important role to attenuate the early phase of DR.
|Titolo:||Modulation of IL-1β and VEGF expression in rat diabetic retinopathy after PACAP administration|
D'AGATA, VELIA MARIA (Corresponding)
|Data di pubblicazione:||2017|
|Appare nelle tipologie:||1.1 Articolo in rivista|