title: Hormonal status modulates circulating endothelial progenitor cells.
abstract: OBJECTIVE
  Endothelial progenitor cells (EPCs) may have an important role in vascular homeostasis and repair.
  
  
  METHODS
  We examined the level of circulating EPCs in pre- (n = 22; mean age 28.7 years), and postmenopausal healthy females without (n = 30; mean age 61.6 years) or under current hormone replacement therapy (HRT) (n = 19; mean age 59.8 years).
  
  
  RESULTS
  Premenopausal females had the highest level of circulating EPCs (0.147 +/- 0.076 per thousand of polymorphnuclear cells). The level of EPCs was lowest in postmenopausal females (0.094 +/- 0.058 per thousand), and increased significantly with HRT on average by 25.5%. In addition, the proliferative capacity of circulating EPCs was assessed under cell culture conditions. This capacity was significantly increased in EPCs isolated from postmenopausal subjects under current HRT as compared to corresponding samples obtained from postmenopausal females without HRT.
  
  
  CONCLUSIONS
  This observation is in line with the hypothesis that the hormonal status in females modulates the cardiovascular risk and that circulating EPCs could be involved in this phenomenon.
authors.affiliation: Division of Cardiology, St. Josef-Hospital, Ruhr-University Bochum, Gudrunstrasse 56, 44791, Bochum, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Bulut
authors.forename: Nadine
authors.initials: N
authors.lastname: Albrecht
authors.forename: Matthias
authors.initials: M
authors.lastname: Imöhl
authors.forename: Bülent
authors.initials: B
authors.lastname: Günesdogan
authors.forename: Nadine
authors.initials: N
authors.lastname: Bulut-Streich
authors.forename: Jan
authors.initials: J
authors.lastname: Börgel
authors.forename: Christoph
authors.initials: C
authors.lastname: Hanefeld
authors.forename: Michael
authors.initials: M
authors.lastname: Krieg
authors.forename: Andreas
authors.initials: A
authors.lastname: Mügge
mesh_terms: D000328:Adult; D018952:Antigens, CD34 / Q000032:analysis; D049109:Cell Proliferation; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000737:chemistry / Q000166:cytology*; D004958:Estradiol / Q000097:blood; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood; D017697:Premenopause / Q000097:blood; D011374:Progesterone / Q000097:blood*; D013234:Stem Cells / Q000737:chemistry / Q000166:cytology*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000032:analysis
chemical_list: D018952:Antigens, CD34; D011374:Progesterone; D004958:Estradiol; D040301:Vascular Endothelial Growth Factor Receptor-2