Advanced glycation end products increase endothelial permeability through the RAGE/Rho signaling pathway

Although increased vascular permeability is known to be a major characteristic of diabetic vasculopathy, the precise mechanisms and relevance of advanced glycation end products (AGE) to hyperpermeability of vessels remains unclear. Here, we studied changes in cytoskeletal configuration and the signaling mechanism induced by AGE in human endothelial cells. AGE-BSA stimulation induced Rho activation, intercellular gap formation, prominent actin stress fiber and cell contraction without changing VE-cadherin, and subsequently transendothelial diffusion of FITC-labeled dextran. These processes induced by AGE-BSA were inhibited by either Rho-kinase inhibitor Y27632 or anti-RAGE antibody. We also showed that RhoA and RAGE spontaneously formed a complex. These findings suggest that activation of RAGE/Rho is involved in AGE-BSA-induced hyperpermeability through gap formation and actin reorganization in diabetes.