Figure 1

Treatment of endothelial cells with high-concentration glucose leads to the disintegration of adherens junctions. A, Tyrosine phosphorylation of VE-cad (PY731), Src (PY416), and Pyk2 (PY402) was induced in human umbilical vein endothelial cells (HUVECs) after treatment with glucose for 24 h using phosphospecific antibodies. B, Treatment of HUVECs with high concentration of glucose leads to tyrosin phosphorylation of VE-cadherin, VE-caherin was immunoprecipitated and then blotted with 4G10 anti phospho-tyrosine antibody. C, Treatment of HUVECs with 20 mM glucose for 24 h led to the dissociation of β-catenin from VE-cad. VE-cad antibody was used for immunoprecipitation, and β-catenin and VE-cad antibodies were used for the detection of each respective protein. mIgG (mouse non-immune IgG) was used as an immunoprecipitation control. D, E, Treatment of HUVECs with the indicated concentrations of glucose for 24 h increased the transendothelial migration (TEM) of THP-1 cells and primary human peripheral blood monocytes. TEM of THP-1 cells (D) and primary human peripheral blood monocytes (E) were evaluated by using a transwell assay. Calcein-labeled THP-1 cells/ primary human peripheral blood monocytes were quantified by using a fluorescence plate reader. Data are expressed as the mean ± SD from triplicate experiments. F, G, Treatment of HUVECs with the indicated concentrations of mannitol and 3-O-methyl-D glucose for 24 h did not significantly affect the tyrosine phosphorylation of VE-cad. H, Treatment of human aortic endothelial cells with the indicated concentrations of glucose for 24 h led to tyrosine phosphorylation of VE-cad. *P < 0.05, **P < 0.01, ***P < 0.001 vs. control. Each experiment was independently performed 3 to 4 times.