Chen Jian-Xiong, Zeng Heng, Lawrence Mayme L, Blackwell Timothy S, Meyrick Barbara
Center for Lung Research, Vanderbilt Univ. Medical Center, MCN T-1217, Nashville, TN 37232-2650, USA.
Am J Physiol Heart Circ Physiol. 2006 Oct;291(4):H1563-72. doi: 10.1152/ajpheart.01081.2005. Epub 2006 May 5.
Reactive oxygen species (ROS) play a central role in the pathogenesis of many cardiovascular diseases, such as atherosclerosis and hypertension. Endothelial NADPH oxidase is the major source of intracellular ROS. The present study investigated the role of endothelial NADPH oxidase-derived ROS in angiopoietin-1 (Ang-1)-induced angiogenesis. Exposure of porcine coronary artery endothelial cells (PCAECs) to Ang-1 (250 ng/ml) for periods up to 30 min led to a transient and dose-dependent increase in intracellular ROS. Thirty minutes of pretreatment with the NADPH oxidase inhibitors diphenylene iodinium (DPI, 10 microM) and apocynin (200 microM) suppressed Ang-1-stimulated ROS. Pretreatment with either DPI or apocynin also significantly attenuated Ang-1-induced Akt and p44/42 MAPK phosphorylation. In addition, inhibition of NADPH oxidase significantly suppressed Ang-1-induced endothelial cell migration and sprouting from endothelial spheroids. Using mouse heart microvascular endothelial cells from wild-type (WT) mice and mice deficient in the p47(phox) component of NADPH oxidase (p47(phox-/-)), we found that although Ang-1 stimulated intracellular ROS, Akt and p42/44 MAPK phosphorylation, and cell migration in WT cells, the responses were strikingly suppressed in cells from the p47(phox-/-) mice. Furthermore, exposure of aortic rings from p47(phox-/-) mice to Ang-1 demonstrated fewer vessel sprouts than WT mice. Inhibition of the Tie-2 receptor inhibited Ang-1-induced endothelial migration and vessel sprouting. Together, our data strongly suggest that endothelial NADPH oxidase-derived ROS play a critical role in Ang-1-induced angiogenesis.
活性氧（ROS）在许多心血管疾病（如动脉粥样硬化和高血压）的发病机制中起着核心作用。内皮型NADPH氧化酶是细胞内ROS的主要来源。本研究调查了内皮型NADPH氧化酶衍生的ROS在血管生成素-1（Ang-1）诱导的血管生成中的作用。将猪冠状动脉内皮细胞（PCAECs）暴露于Ang-1（250 ng/ml）长达30分钟，导致细胞内ROS出现短暂的剂量依赖性增加。用NADPH氧化酶抑制剂二苯基碘鎓（DPI，10 microM）和阿朴吗啡（200 microM）预处理30分钟可抑制Ang-1刺激的ROS。用DPI或阿朴吗啡预处理也显著减弱了Ang-1诱导的Akt和p44/42 MAPK磷酸化。此外，抑制NADPH氧化酶可显著抑制Ang-1诱导的内皮细胞迁移和内皮球的出芽。使用来自野生型（WT）小鼠和缺乏NADPH氧化酶p47（phox）成分的小鼠（p47（phox-/-））的小鼠心脏微血管内皮细胞，我们发现尽管Ang-1刺激了WT细胞内的ROS、Akt和p42/44 MAPK磷酸化以及细胞迁移，但在p47（phox-/-）小鼠的细胞中这些反应受到显著抑制。此外，将p47（phox-/-）小鼠的主动脉环暴露于Ang-1后，其血管芽比WT小鼠少。抑制Tie-2受体可抑制Ang-1诱导的内皮迁移和血管芽生成。总之，我们的数据强烈表明内皮型NADPH氧化酶衍生的ROS在Ang-1诱导的血管生成中起关键作用。
