title: Laminar shear stress enhances endothelial cell survival through a NADPH oxidase 2-dependent mechanism.
abstract: The beneficial effects of laminar shear stress (LSS) due to blood flow include inhibition of endothelial cell death, but the associated mechanism is not well understood. This issue was addressed in the present study. In a normal growth medium, the endothelial cell death rate was below 5%, but this value increased beyond 30% when the serum was depleted. However, when cells were exposed to LSS during the serum depletion period, cell viability recovered to the levels of the serum-provided cells. The pro-survival effect of LSS was not affected by l-arginine methyl ester, but it was abrogated by apocynin, indicating that NADPH oxidases (NOX) play key roles in the mechanism. The pro-survival effect of LSS was reduced by NOX2 siRNA, but not by NOX4 siRNA. LSS increased the expressions of p47(phox) and p67(phox), the subunits of NOX2 complex. These observations suggest that LSS prevents apoptotic death of endothelial cells through a NOX2-dependent mechanism.
authors.affiliation: Department of Molecular Medicine, Cell and Matrix Research Institute, BK21 Medical Education Program for Human Resources, Kyungpook National University School of Medicine, Daegu 700-422, Republic of Korea.
authors.forename: Hyeona
authors.initials: H
authors.lastname: Jeon
authors.forename: Yong Chool
authors.initials: YC
authors.lastname: Boo
mesh_terms: D017209:Apoptosis; D001783:Blood Flow Velocity; D018929:Cell Culture Techniques; D002470:Cell Survival; D016895:Culture Media, Serum-Free; D004730:Endothelium, Vascular / Q000502:physiology*; D061307:Human Umbilical Vein Endothelial Cells / Q000502:physiology; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D033081:Shear Strength; D013314:Stress, Mechanical
chemical_list: D016895:Culture Media, Serum-Free; D008562:Membrane Glycoproteins; D034741:RNA, Small Interfering; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases