title: Dynamic changes of vascular endothelial growth factor and angiopoietin-1 in association with circulating endothelial progenitor cells after severe traumatic brain injury.
abstract: BACKGROUND
  Vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) can promote angiogenesis and vascular stability after brain injury. Circulating endothelial progenitor cells (EPCs) also play a crucial role in neovascularization and tissue repair after traumatic brain injury (TBI). We sought to compare the expression of VEGF and Ang-1 in serum and the circulating EPCs in patients after severe TBI with that of healthy control subjects.
  
  
  METHODS
  We obtained peripheral blood and serum samples from 21 patients with severe TBI and 11 healthy control subjects. EPCs in blood samples from severe TBI patients and healthy controls were quantified by flow cytometry 1 day, 4 days, 7 days, 14 days, and 21 days after severe TBI. VEGF and Ang-1 were measured by enzyme linked immunosorbent assay at the same time points.
  
  
  RESULTS
  Compared with control subjects, circulating EPCs in patients with severe TBI decreased 4 days (p < 0.05), but increased 7 days and 14 days (p < 0.05) after TBI. VEGF increased significantly during the follow-up period (p < 0.05). Ang-1 increased gradually and reached peak at 7 days and 14 days after TBI. The circulating EPCs were significantly correlated with VEGF and Ang-1 at 7 days and 14 days after severe TBI.
  
  
  CONCLUSIONS
  Our results suggest that the increased VEGF and Ang-1 are closely related to increase in circulating EPCs in response to severe TBI, which may be needed for vascular repairs after severe TBI.
authors.affiliation: Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin 300052, PR China.
authors.forename: Dasen
authors.initials: D
authors.lastname: Gong
authors.forename: Sai
authors.initials: S
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Jingfei
authors.initials: J
authors.lastname: Dong
authors.forename: Xinbin
authors.initials: X
authors.lastname: Guo
authors.forename: Mu
authors.initials: M
authors.lastname: Hao
authors.forename: Yue
authors.initials: Y
authors.lastname: Tu
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Diao
authors.forename: Jianning
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D042683:Angiopoietin-1 / Q000097:blood*; D001930:Brain Injuries / Q000097:blood*; D016022:Case-Control Studies; D042783:Endothelial Cells / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D013234:Stem Cells / Q000502:physiology*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood
chemical_list: D042683:Angiopoietin-1; D042461:Vascular Endothelial Growth Factor A