Racial differences in the responses to shear stress in human umbilical vein endothelial cells
Genre
Journal ArticleDate
2011-01-01Author
Feairheller, DLPark, JY
Rizzo, V
Kim, B
Brown, MD
Subject
African AmericanHUVECs
NADPH oxidase
oxidative stress
shear stress
African Americans
Biomarkers
Catalase
Cell Culture Techniques
Cells, CulturedEuropean Continental Ancestry GroupHuman Umbilical Vein Endothelial CellsHumansNADPH OxidasesNitric OxideNitric Oxide Synthase Type IIIOxidative StressStress, MechanicalSuperoxide Dismutase
Permanent link to this record
http://hdl.handle.net/20.500.12613/5521Metadata
Show full item recordDOI
10.2147/VHRM.S22435Abstract
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/cm2), and moderate LSS (20 dyne/cm2). 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. Conclusion: 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. © 2011 Feairheller et al, publisher and licensee Dove Medical Press Ltd.Citation to related work
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