title: Racial differences in the responses to shear stress in human umbilical vein endothelial cells.
abstract: BACKGROUND
  African American ethnicity is an independent risk factor for exaggerated oxidative stress, which is related to inflammation, hypertension, and cardiovascular disease. Recently, we reported that in vitro oxidative stress and inflammation levels differ between African American and Caucasian human umbilical vein endothelial cells (HUVECs), African American HUVECs having higher levels of both. However, it remains to be shown whether the cells would respond differently to external stimuli.
  
  
  METHODS
  We used a cone and plate viscometer to apply laminar shear stress (LSS) as an aerobic exercise mimetic to compare the responses by race. HUVECs were exposed to static conditions (no LSS), low LSS (5 dyne/cm(2)), and moderate LSS (20 dyne/cm(2)).
  
  
  RESULTS
  It was found that African American HUVECs had higher levels of oxidative stress under static conditions, and when LSS was applied protein expression levels (NADPH oxidase NOX2, NOX4 and p47phox subunits, eNOS, SOD2, and catalase) and biomarkers (NO, SOD, and total antioxidant capacity) were modulated to similar levels between race.
  
  
  CONCLUSIONS
  African American HUVECs may be more responsive to LSS stimulus indicating that aerobic exercise prescriptions may be valuable for this population since the potential exists for large in vivo improvements in oxidative stress levels along the endothelial layer in response to increased shear flow.
authors.affiliation: Hypertension, Molecular and Applied Physiology Laboratory, School of Medicine, Temple University, Philadelphia, PA, USA.
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Feairheller
authors.forename: Joon-Young
authors.initials: JY
authors.lastname: Park
authors.forename: Victor
authors.initials: V
authors.lastname: Rizzo
authors.forename: Boa
authors.initials: B
authors.lastname: Kim
authors.forename: Michael D
authors.initials: MD
authors.lastname: Brown
mesh_terms: D001741:Black or African American; D015415:Biomarkers / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism*; D006801:Humans; D019255:NADPH Oxidases / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D018384:Oxidative Stress; D013314:Stress, Mechanical; D013482:Superoxide Dismutase / Q000378:metabolism; D044465:White People; D000099156:Superoxide Dismutase 2
chemical_list: D015415:Biomarkers; D002374:Catalase; D019255:NADPH Oxidases; D009569:Nitric Oxide; D052250:Nitric Oxide Synthase Type III; D013482:Superoxide Dismutase; D000099156:Superoxide Dismutase 2; C496314:NOS3 protein, human