[Effects of angiotensin II on peripheral blood endothelial progenitor cells].
OBJECTIVE
To investigate the effect of Angiotensin II (AngII) on the quantity proliferation, migration and adhesion of endothelial progenitor cells (EPCs).


METHODS
Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation and then the cells were plated on fibronectin-coated culture dishes. After 7 days of culture, several groups of attached cells were incubated with AngII (to make a series of concentrations: 10(-3) mol/L, 10(-5) mol/L, 10(-7) mol/L, 10(-9) mol/L) or vehicle control for the respective time points (6, 12, 24 h and 48 h). In other groups of EPCs, valsartan (1 x 10(-5) mol/L) and AngII were added to the culture medium together.EPCs were characterized as adherent cells double positive for DiLDL-uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. EPCs were further documented by demonstrating the expression of KDR, VEGFR-2 and AC133 with flow cytometry. EPCs proliferation, migration and in vitro vasculogenesis activity were assayed with MTT assay, modified Boyden chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating MNCs on fibronectin-coated dishes.


RESULTS
Incubation of isolated human MNCs with AngII increased the number of EPCs, with a maximum at 10(-3) mol/L after 24 hours (P < 0.01). In addition, AngII promotes EPCs proliferative, migratory, adhesive and in vitro vasculogenetic capacity. The effect of AngII was blocked by pretreatment of valsartan.


CONCLUSIONS
It is suggested that angiotensin II may promote EPCs augmentation and enhance its functional activity through angiotensin receptor.
Yuan
Hong
H
Department of Cardiovascular Diseases, the First Affiliated Hospital, Medical School of Zhejiang University, Hangzhou 310003, China. yuanhongy@163.com
Chen
Jun-Zhu
JZ
Wang
Xing-Xiang
XX
D000804:Angiotensin II / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D018919:Neovascularization, Physiologic / Q000187:drug effects; D013234:Stem Cells / Q000187:drug effects* / Q000502:physiology; D013777:Tetrazoles / Q000494:pharmacology; D014633:Valine / Q000031:analogs & derivatives / Q000494:pharmacology; D000068756:Valsartan
D013777:Tetrazoles; D000804:Angiotensin II; D000068756:Valsartan; D014633:Valine