title: Local over-expression of VEGF-DΔNΔC in the uterine arteries of pregnant sheep results in long-term changes in uterine artery contractility and angiogenesis.
abstract: BACKGROUND
  The normal development of the uteroplacental circulation in pregnancy depends on angiogenic and vasodilatory factors such as vascular endothelial growth factor (VEGF). Reduced uterine artery blood flow (UABF) is a common cause of fetal growth restriction; abnormalities in angiogenic factors are implicated. Previously we showed that adenovirus (Ad)-mediated VEGF-A165 expression in the pregnant sheep uterine artery (UtA) increased nitric oxide synthase (NOS) expression, altered vascular reactivity and increased UABF. VEGF-D is a VEGF family member that promotes angiogenesis and vasodilatation but, in contrast to VEGF-A, does not increase vascular permeability. Here we examined the effect of Ad.VEGF-DΔNΔC vector encoding a fully processed form of VEGF-D, on the uteroplacental circulation.
  
  
  METHODS
  UtA transit-time flow probes and carotid artery catheters were implanted in mid-gestation pregnant sheep (n = 5) to measure baseline UABF and maternal haemodynamics respectively. 7-14 days later, after injection of Ad.VEGF-DΔNΔC vector (5×10(11) particles) into one UtA and an Ad vector encoding β-galactosidase (Ad.LacZ) contralaterally, UABF was measured daily until scheduled post-mortem examination at term. UtAs were assessed for vascular reactivity, NOS expression and endothelial cell proliferation; NOS expression was studied in ex vivo transduced UtA endothelial cells (UAECs).
  
  
  RESULTS
  At 4 weeks post-injection, Ad.VEGF-DΔNΔC treated UtAs showed significantly lesser vasoconstriction (Emax144.0 v/s 184.2, p = 0.002). There was a tendency to higher UABF in Ad.VEGF-DΔNΔC compared to Ad.LacZ transduced UtAs (50.58% v/s 26.94%, p = 0.152). There was no significant effect on maternal haemodynamics. An increased number of proliferating endothelial cells and adventitial blood vessels were observed in immunohistochemistry. Ad.VEGF-DΔNΔC expression in cultured UAECs upregulated eNOS and iNOS expression.
  
  
  CONCLUSIONS
  Local over-expression of VEGF-DΔNΔC in the UtAs of pregnant mid-gestation sheep reduced vasoconstriction, promoted endothelial cell proliferation and showed a trend towards increased UABF. Studies in cultured UAECs indicate that VEGF-DΔNΔC may act in part through upregulation of eNOS and iNOS.
authors: Institute for Women's Health, UCL, London, United Kingdom; Centre for Cardiovascular Biology and Medicine, Division of Medicine, Rayne Building, UCL, London, United Kingdom.
authors: Vedanta
authors: V
authors: Mehta
authors: Institute for Women's Health, UCL, London, United Kingdom.
authors: Khalil N
authors: KN
authors: Abi-Nader
authors: Institute for Women's Health, UCL, London, United Kingdom.
authors: Panicos
authors: P
authors: Shangaris
authors: Institute for Women's Health, UCL, London, United Kingdom.
authors: S W Steven
authors: SW
authors: Shaw
authors: Institute for Women's Health, UCL, London, United Kingdom.
authors: Elisa
authors: E
authors: Filippi
authors: Institute for Women's Health, UCL, London, United Kingdom.
authors: Elizabeth
authors: E
authors: Benjamin
authors: BSU, Royal Veterinary College, Camden, London, United Kingdom.
authors: Michael
authors: M
authors: Boyd
authors: Institute for Women's Health, UCL, London, United Kingdom.
authors: Donald M
authors: DM
authors: Peebles
authors: Centre for Cardiovascular Biology and Medicine, Division of Medicine, Rayne Building, UCL, London, United Kingdom.
authors: John
authors: J
authors: Martin
authors: Centre for Cardiovascular Biology and Medicine, Division of Medicine, Rayne Building, UCL, London, United Kingdom.
authors: Ian
authors: I
authors: Zachary
authors: Institute for Women's Health, UCL, London, United Kingdom.
authors: Anna L
authors: AL
authors: David
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D001783:Blood Flow Velocity; D002339:Carotid Arteries / Q000502:physiology; D002408:Catheters, Indwelling; D049109:Cell Proliferation; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D017930:Genes, Reporter; D005822:Genetic Vectors; D018919:Neovascularization, Physiologic; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism; D021041:Placental Circulation / Q000502:physiology*; D011247:Pregnancy; D012756:Sheep; D055988:Uterine Artery / Q000166:cytology / Q000378:metabolism*; D014599:Uterus / Q000098:blood supply* / Q000166:cytology / Q000378:metabolism; D042643:Vascular Endothelial Growth Factor D / Q000235:genetics* / Q000378:metabolism; D014661:Vasoconstriction; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D042643:Vascular Endothelial Growth Factor D; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D001616:beta-Galactosidase