title: Advanced glycation end products impair the migration, adhesion and secretion potentials of late endothelial progenitor cells.
abstract: BACKGROUND
  Endothelial progenitor cells (EPCs), especially late EPCs, play a critical role in endothelial maintenance and repair, and postnatal vasculogenesis. Advanced glycation end products (AGEs) have been shown to impair EPC functions, such as proliferation, migration and adhesion. However, their role in the regulation of the production of vasoactive substances in late EPCs is less well defined.
  
  
  METHODS
  Passages of 3~5 EPCs, namely late EPCs, were cultured with different concentrations (0~500 μg/ml) of AGEs, and the apoptosis, adhesion and migration were subsequently determined. The release of vasoactive substances, such as stromal cell-derived factor-1 (SDF-1), nitric oxide (NO), prostaglandin I2 (PGI2), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA), and in addition the activity of superoxide dismutase (SOD), were evaluated by ELISA. At the same time, the gene and protein expressions of CXCR4 were assayed by real-time RT-PCR and western-blot.
  
  
  RESULTS
  AGEs promoted late EPC apoptosis. Moreover, AGEs impaired late EPC migration and adhesion in a concentration-dependent manner. Accordingly, the production of SDF-1 was decreased by AGEs. Although the CXCR4 expressions of late EPCs were up-regulated for AGE concentrations of 50, 100 or 200 μg/ml, a marked decrease was observed for the higher concentration of 500 μg/ml. Furthermore, co-culturing with AGEs decreased the levels of NO, t-PA, PGI2, and the activity of SOD but up-regulated the production of PAI-1.
  
  
  CONCLUSIONS
  Our data provide evidence that AGEs play an important role in impairing late EPC functions, which could contribute to the development of vascular diseases in diabetes.
authors.affiliation: Medicine Research Center, Weifang Medical College, Weifang, Shandong, 261053, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Zhang
authors.forename: Xiumei
authors.initials: X
authors.lastname: Guan
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Cui
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Wang
authors.forename: Hairong
authors.initials: H
authors.lastname: Chu
authors.forename: Min
authors.initials: M
authors.lastname: Cheng
mesh_terms: D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D002448:Cell Adhesion; D002465:Cell Movement; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000378:metabolism; D042783:Endothelial Cells / Q000378:metabolism* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D011464:Epoprostenol / Q000378:metabolism; D005786:Gene Expression Regulation; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D017395:Plasminogen Activator Inhibitor 1 / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D019718:Receptors, CXCR4 / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000378:metabolism* / Q000473:pathology; D013482:Superoxide Dismutase / Q000378:metabolism; D010959:Tissue Plasminogen Activator / Q000378:metabolism
chemical_list: D054377:Chemokine CXCL12; C486264:Cxcr4 protein, rat; D017127:Glycation End Products, Advanced; D017395:Plasminogen Activator Inhibitor 1; D019718:Receptors, CXCR4; D009569:Nitric Oxide; D011464:Epoprostenol; D013482:Superoxide Dismutase; D010959:Tissue Plasminogen Activator