title: In vitro shear stress modulates antithrombogenic potentials of human endothelial progenitor cells.
abstract: BACKGROUND
  Recent study suggested that endothelial progenitor cells (EPCs), a novel therapeutic approach for endothelial dysfunction, present limited antithrombogenic potentials. However, few attempts have been done to improve the antithrombogenic potentials of EPCs. Our previous study proved that in vitro shear stress contributes to the increase in t-PA production by human EPCs. Here, we further investigated whether in vitro shear stress contributes to the secretion of antithrombogenic substances including plasminogen activator inhibitor-1 (PAI-1) and prostaglandin I(2) (PGI(2)) by human EPCs.
  
  
  METHODS
  The peripheral blood mononuclear cells of healthy subjects were induced into EPCs. Then the human EPCs were treated with four levels of shear stress including stationary condition low media and high flow shear stress. The production of PAI-1 and 6-keto-prostaglandin F1(1alpha)(6-Keto-PGF(1alpha)) by human EPCs with shear stress treatment were measured.
  
  
  RESULTS
  In vitro medium and high flow shear stress inhibited PAI-1 secretion by human EPCs, but low flow shear stress had no effect on PAI-1 secretion by human EPCs. All levels of shear stress significantly increased 6-Keto-PGF(1alpha )production by human EPCs in a dose-dependent manner.
  
  
  CONCLUSIONS
  The present study demonstrates that in vitro shear stress can promote PGI(2 )secretion and inhibit PAI-1 secretion by human EPCs, which improves the antithrombogenic potentials of human EPCs.
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.forename: Jie-mei
authors.initials: JM
authors.lastname: Wang
authors.forename: Li-chun
authors.initials: LC
authors.lastname: Wang
authors.forename: Long
authors.initials: L
authors.lastname: Chen
authors.forename: Chang
authors.initials: C
authors.lastname: Tu
authors.forename: Chu-fang
authors.initials: CF
authors.lastname: Luo
authors.forename: An-li
authors.initials: AL
authors.lastname: Tang
authors.forename: Sheng-Ming
authors.initials: SM
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Tao
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism*; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000378:metabolism*; D011464:Epoprostenol / Q000378:metabolism*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000166:cytology; D017395:Plasminogen Activator Inhibitor 1 / Q000378:metabolism*; D012212:Rheology; D013234:Stem Cells / Q000378:metabolism*; D013314:Stress, Mechanical
chemical_list: D017395:Plasminogen Activator Inhibitor 1; C051321:SERPINE1 protein, human; D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol