Diabetic Retinopathy is a common complication of Diabetes Mellitus that results in blindness. This complication of diabetes occurs when tight junctions between capillary retinal endothelial cells disassemble and allow blood flow into the retina resulting to damage of neuronal cells. It has been demonstrated that Zonular Occludin (ZO-1) phosphorylation causes the disassembly of proteins in these tight junctions. Diabetes causes elevated levels of growth factors, such as vascular endothelial growth factor (VEGF) in the vitreous humor of the eye. VEGF has been shown to stimulate the cellular signaling of the pathway that leads to the phosphorylation of ZO-1. This work is aimed at identifying the pathway that is activated by VEGF and results in the ZO-1 phosphorylation in Diabetic Retinopathy. It has been hypothesized that the mitogen-activated protein kinase (MAPK) pathway is involved. This experiment studied the levels of ZO-1 phosphorylation in an appropriate cellular model; Madin-Darby Canine Kidney (MDCK) cells treated with platelet derived growth factor (PDGF). Cells were treated with PDGF in the absence and presence of an inhibitor to the MAPK pathway (UTAK-100). After 60 minutes of treatment MDCK cells were lysed to perform immunoprecipitation of ZO-1. An SDS-PAGE was completed to determine alterations in phosphorylation levels of ZO-1. We expect to see decreased levels of ZO-1 phosphorylation with inhibition of the MAPK pathway. This will indicate that diabetic retinopathy is caused by the disassembly of tight junctions in endothelial cells from ZO-1 phosphorylation through the MAPK pathway.

Determination of the zonula occludin-1 phosphorylation pathway: Tight junction disassembly in diabetic retinopathy

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.