title: Exercise increases soluble vascular endothelial growth factor receptor-1 (sFlt-1) in circulation of healthy volunteers.
abstract: BACKGROUND
  Physical inactivity increases the risk of cancer and atherosclerosis; the impaired regulation of angiogenesis is often associated with the development of these diseases. We hypothesize that exercise increases circulating sFlt-1, an endogenous VEGF inhibitor, which may functionally decrease plasma levels of free VEGF.
  
  
  METHODS
  5 healthy male adults were assigned to a treadmill exercise study. The peak speed and the time spent at peak speed on the treadmill were 4.8+/-1.0 miles/h and 6.8+/-2.6 minutes, respectively. Plasma levels of sFlt-1 and VEGF were determined using ELISA (R&D Systems).
  
  
  RESULTS
  Basal plasma levels of sFlt-1 (before exercise) were 48.8+/-9.0 pg/ml. Plasma levels of sFlt-1 increased to 72.9+/-14.6 pg/ml at 0.5 h after exercise, compared to the basal levels (49% higher, P=0.0048). The plasma levels then returned to 47.5+/-14.3 and 43.3+/-10.2 pg/ml, at 2 and 6 h after exercise, respectively. There was a significant positive correlation between % increase in plasma levels of sFlt-1 and total peak oxygen consumption during exercise (R2=0.8244; P<0.01). Basal plasma levels of unbound VEGF were 37.3+/-7.7 pg/ml, then decreased to 28.2+/-6.3, 17.5+/-2.5, and 26.6+/-6.4 pg/ml, at 0.5, 2, and 6 h, respectively, after exercise. There was a significant increase in basal plasma levels of sFlt-1 after repeated exercise for 2 weeks.
  
  
  CONCLUSIONS
  We have demonstrated that circulating sFlt-1 is significantly increased by exercise in healthy volunteers, which is functionally associated with a transient decrease in circulating free VEGF. This data may provide new insight into the molecular links between physical inactivity and risk of cancer and atherosclerosis.
authors.affiliation: Department of Physiology & Biophysics, University of Mississippi Medical Center, Jackson, MS 39216-4505, USA.
authors.forename: Amelia Purser
authors.initials: AP
authors.lastname: Bailey
authors.forename: Megan
authors.initials: M
authors.lastname: Shparago
authors.forename: Jian-Wei
authors.initials: JW
authors.lastname: Gu
mesh_terms: D000328:Adult; D050197:Atherosclerosis / Q000097:blood / Q000209:etiology / Q000517:prevention & control; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D016222:Fibroblast Growth Factor 2 / Q000097:blood; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000097:blood / Q000209:etiology / Q000517:prevention & control; D012307:Risk Factors; D012995:Solubility; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors / Q000097:blood; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000097:blood*
chemical_list: D042461:Vascular Endothelial Growth Factor A; D016222:Fibroblast Growth Factor 2; C501162:FLT1 protein, human; D040281:Vascular Endothelial Growth Factor Receptor-1