Inhibition of Notch signaling leads to increased intracellular ROS by up-regulating Nox4 expression in primary HUVECs.
The essential roles of Notch pathway in angiogenesis have been reported for years. However, how Notch pathway plays its role in regulating endothelial cells remains largely unknown. In this study we found that blockade of Notch signaling with a γ-secretase inhibitor increased reactive oxygen species (ROS) in primary human umbilical vein endothelial cells (HUVECs) under both normaxic and ischemia/reperfusion (I/R) conditions. Abruption of ROS generation with ROS scavengers or specific inhibitors of ROS production in HUVECs abolished Notch blockade-induced HUVEC proliferation, migration and adhesion, suggesting that the regulation of Notch pathway on endothelial cell behavior is at least partially dependent on its down-regulation of ROS level. We further showed that the enhanced generation of ROS after blocking Notch signal was accompanied by augmented expression of Nox4, which led to increased phosphorylation of VEGFR2 and ERK in HUVECs. In summary, our results have shown that Notch signaling regulates ROS generation by suppressing Nox4, and further modulates endothelial cell proliferation, migration and adhesion.
Department of Burns and Cutanous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710038, China.
Wei-Xia
WX
Cai
State Key Laboratory of Cancer Biology, Department of Medical Genetics and Developmental Biology, Fourth Military Medical University, Xi'an 710038, China.
Liang
L
Liang
State Key Laboratory of Cancer Biology, Department of Medical Genetics and Developmental Biology, Fourth Military Medical University, Xi'an 710038, China.
Li
L
Wang
Department of Burns and Cutanous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710038, China.
Jun-Tao
JT
Han
Department of Burns and Cutanous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710038, China.
Xiong-Xiang
XX
Zhu
State Key Laboratory of Cancer Biology, Department of Medical Genetics and Developmental Biology, Fourth Military Medical University, Xi'an 710038, China. Electronic address: huahan@fmmu.edu.cn.
Hua
H
Han
Department of Burns and Cutanous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710038, China. Electronic address: hudahai@fmmu.edu.cn.
Da-Hai
DH
Hu
State Key Laboratory of Cancer Biology, Department of Medical Genetics and Developmental Biology, Fourth Military Medical University, Xi'an 710038, China. Electronic address: pingzhang0622@gmail.com.
Ping
P
Zhang
D053829:Amyloid Precursor Protein Secretases / Q000037:antagonists & inhibitors; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D061307:Human Umbilical Vein Endothelial Cells / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism*; D018919:Neovascularization, Physiologic; D009842:Oligopeptides / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism*; D051880:Receptors, Notch / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D015854:Up-Regulation
D009842:Oligopeptides; D017382:Reactive Oxygen Species; D051880:Receptors, Notch; C523462:benzyloxycarbonyl-leucyl-leucyl-norleucinal; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases; C498910:NOX4 protein, human; D053829:Amyloid Precursor Protein Secretases
HUVECs; Notch signaling; Nox4; ROS; VEGFR2