Advanced glycation endproducts enhance proliferation, but not tube formation in choroidal microvascular endothelial cells / 国际眼科杂志(Guoji Yanke Zazhi)

ABSTRACT

● AIM: To investigate the role of advanced glycation endproducts (AGEs) in the pathogenesis of age-related macular degeneration (AMD).● METHODS: Bovine choroidal endothelial cells (CEC)were isolated by the modified protocol using lycopersicon esculentum agglutinin coated Dynabeads, and identiffed by immunocytochemical staining with anti-Factor Ⅷ antibody and uptaking of dil-acetylated low-density lipoprotein (dil-ac-LDL). AGEs were prepared by incubating 50g/L bovine serum albumin and 150g/L glucose at 37℃ for 6wk, which were characterized by dot blot assay with anti-AGEs antibody. CEC proliferation was evaluated using 3,(4,5-dimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay, and tube formation in CEC was determined by a Vitrogen system.● RESULTS: More than 90% of the cultured cells were positive to Factor V immunostaining and had the ability to uptake dil-ac-LDL, which were the features of endothelial cells. AGEs we prepared were affinitive to anti-AGEs antibody. After treatment with AGEs for a time course of 3d, CEC proliferation was significantly increased in a dose-dependent manner by AGEs at concentrations between 62.5 and 500mg/L. The cytokine,basic fibroblast growth factor (bFGF), enhanced strongly tube-like structure formation in CEC to 124% (P＜0.05)above that of untreated controls. In this condition, AGEs at the concentrations of 500 and 50mg/L showed no effect on CEC tube formation (P＞0.05).● CONCLUSION: The present study demonstrated that CEC proliferation was increased by AGEs, however, regarding there was no statistically effect on CEC tube formation. These findings confirm and extend that AGEs could be a potential initiator in the pathogenesis of choroidal neovascularization in exudative AMD, at least in part, through enhancement of CEC proliferation.