title: Plasma angiopoietin-1, angiopoietin-2, and angiopoietin receptor tie-2 levels in congestive heart failure.
abstract: OBJECTIVE
  The goal of this research was to test the hypothesis that plasma angiopoietin (Ang-1), its soluble receptor tie-2, and Ang-2 levels would be abnormal in patients with acute and chronic congestive heart failure (CHF) when compared with healthy controls.
  
  
  BACKGROUND
  Increased plasma vascular endothelial growth factor (VEGF) in CHF is suggestive of excess angiogenesis-possibly driven by tissue hypoxia. However, other growth factors also have a major role in angiogenesis, such as those of the angiopoietin family (e.g., Ang-1, which exerts its activity via its receptor, tie-2, and Ang-2).
  
  
  METHODS
  We recruited 39 patients with acute CHF (mean age 67 +/- 10 years), 40 patients with chronic CHF (mean age 63 +/- 9 years), and 17 healthy controls (mean age 67 +/- 7 years), all in sinus rhythm. Citrated plasma was analyzed for Ang-1, Ang-2, tie-2, and VEGF by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Angiopoietin-2 (p < 0.001), tie-2 (p < 0.05), and VEGF (p < 0.05) levels were all higher in acute CHF compared with controls. The Ang-2 levels were higher in acute CHF compared with chronic CHF (p < 0.001), but there were no significant differences in Ang-1 levels between the groups. The principal significant correlations were between Ang-2 and tie-2 (Spearman, r = 0.407; p < 0.0001) and between Ang-2 and ejection fraction (r = -0.241, p = 0.043). Although only marginally raised, levels of VEGF correlated with both Ang-2 (r = 0.468, p < 0.001) and tie-2 (r = 0.569, p < 0.001).
  
  
  CONCLUSIONS
  We have demonstrated abnormal levels of Ang-2 and tie-2, but normal Ang-1, in both CHF patients. These abnormalities may, alongside VEGF, indicate a role for these angiogenic factors in the pathophysiology of CHF.
authors.affiliation: Haemostasis Thrombosis and Vascular Biology Unit, University Department of Medicine, City Hospital, Birmingham B18 7QH, England, UK.
authors.forename: Aun Yeong
authors.initials: AY
authors.lastname: Chong
authors.forename: Graham J
authors.initials: GJ
authors.lastname: Caine
authors.forename: Bethan
authors.initials: B
authors.lastname: Freestone
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Blann
authors.forename: Gregory Y H
authors.initials: GY
authors.lastname: Lip
mesh_terms: D000208:Acute Disease; D000368:Aged; D042683:Angiopoietin-1 / Q000097:blood*; D042702:Angiopoietin-2 / Q000097:blood*; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D042787:Receptor, TIE-2 / Q000097:blood*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood
chemical_list: D042683:Angiopoietin-1; D042702:Angiopoietin-2; D042461:Vascular Endothelial Growth Factor A; D042787:Receptor, TIE-2