VEGF-A/VEGFR-2 Signaling Leading to cAMP Response Element-Binding Protein Phosphorylation Is a Shared Pathway Underlying the Protective Effect of Preconditioning on Neurons and Endothelial Cells
VEGF-A/VEGFR-2 Signaling Leading to cAMP Response Element-Binding Protein Phosphorylation Is a Shared Pathway Underlying the Protective Effect of Preconditioning on Neurons and Endothelial Cells
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DOI：
10.1523/jneurosci.5497-08.2009
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发表时间：
2009-04-08
影响因子：
5.3
通讯作者：
Huang, Chao-Ching
中科院分区：
文献类型：
--
作者：
Lee, Hsueh-Te;Chang, Ying-Chao;Huang, Chao-Ching
预适应保护内皮细胞和神经元免受缺血损伤。在7日龄幼鼠中，在低氧前1小时结扎颈动脉可损伤同侧大脑半球；相反，在低氧前24小时结扎动脉可提供完全的神经保护。24 h动脉结扎预适应模型的保护作用需要cAMP反应元件结合蛋白(CREB)的激活。我们验证了一种假设，即导致CREB激活的血管内皮生长因子-A/血管内皮细胞生长因子受体-2(VEGFR-2)信号是预适应保护神经元和内皮细胞的共同途径。体内应用反义寡核苷酸(ODN)可抑制VEGFR-1或VEGFR-2的表达，体外应用中和抗体或VEGFR-2抑制剂可抑制VEGFR-2的表达。结扎后24 h，同侧大脑皮质血管内皮细胞和神经元中CREB磷酸化(PCREB)、血管内皮生长因子-A和血管内皮生长因子受体-2的表达增加并共存。阻断血管内皮生长因子-A和血管内皮生长因子受体-2的反义寡核苷酸可降低pCREB，并减弱24 h结扎预适应的保护作用。此外，缺氧-葡萄糖剥夺(OGD)预适应上调了VEGF-A、VEGFR-2和pCREB的水平，并保护永生化的H19-7神经细胞和b.End3血管内皮细胞免受24 h OGD细胞死亡的影响。阻断VEGF-A或VEGFR-2可减少CREB的激活及OGD预适应对神经细胞和内皮细胞的影响。转染丝氨酸-133磷酸化突变体CREB也可抑制OGD预适应的保护作用。我们认为，血管内皮生长因子-A/血管内皮生长因子受体-2信号通路导致CREB的磷酸化是脑发育中预适应诱导的神经元和血管内皮细胞保护作用的共同途径。
Preconditioning protects endothelial cells as well as neurons from ischemic injury. In 7-d-old rat pups, ligating the carotid artery 1 h before hypoxia damaged the ipsilateral cerebral hemisphere; in contrast, ligating the artery 24 h before hypoxia provided complete neuroprotection. The protective effect of the 24 h artery ligation preconditioning model requires the activation of cAMP response element-binding protein (CREB). We tested the hypothesis that vascular endothelial growth factor (VEGF)-A/VEGF receptor-2 (VEGFR-2) signaling that leads to CREB activation is the shared pathway underlying the protective effect of preconditioning in neurons and endothelial cells. VEGF-A, VEGFR-1, or VEGFR-2 was inhibited by antisense oligodeoxynucleotides (ODNs) in vivo and by a VEGF-A neutralizing antibody or VEGFR- 2 inhibitor in vitro. CREB phosphorylation (pCREB) and VEGF-A and VEGFR- 2 expression were increased and colocalized in vascular endothelial cells and neurons in the ipsilateral cerebral cortex 24 h after ligation. The antisense ODN blockades of VEGF-A and VEGFR- 2 decreased pCREB and reduced the protection of 24 h ligation preconditioning. Furthermore, oxygen-glucose deprivation (OGD) preconditioning upregulated VEGF-A, VEGFR- 2, and pCREB levels and protected immortalized H19-7 neuronal cells and b. End3 vascular endothelial cells against 24 h OGD cell death. Blocking VEGF-A or VEGFR- 2 reduced CREB activation and the effects of OGD preconditioning in neuronal cells and endothelial cells. Transfecting a serine-133 phosphorylation mutant CREB also inhibited the protective effect of OGD preconditioning. We conclude that VEGF-A/VEGFR-2 signaling leading to CREB phosphorylation is the shared pathway underlying the preconditioning-induced protective effect in neurons and vascular endothelial cells in the developing brain.