Vascular endothelial growth factor receptor-2 couples cyclo-oxygenase-2 with pro-angiogenic actions of leptin on human endothelial cells.
Vascular endothelial growth factor receptor-2 couples cyclo-oxygenase-2 with pro-angiogenic actions of leptin on human endothelial cells.
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DOI：
10.1371/journal.pone.0018823
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发表时间：
2011-04-18
期刊：
影响因子：
3.7
通讯作者：
Wheeler-Jones CP
中科院分区：
文献类型：
--
作者：
Garonna E;Botham KM;Birdsey GM;Randi AM;Gonzalez-Perez RR;Wheeler-Jones CP
脂肪细胞衍生的激素瘦素影响广泛的细胞类型的行为，现在被认为是促血管生成和促炎症因子。在脉管系统中，这些作用部分通过其直接瘦素受体（ObRb）驱动的对内皮细胞（EC）的作用介导，但负责这些活动的机制尚未建立。在这项研究中，我们试图更全面地定义瘦素刺激的人内皮细胞的炎症和血管生成反应之间的分子联系。免疫印迹研究表明，瘦素增加环氧化酶-2（考克斯-2）的表达（而不是考克斯-1）在培养的人脐静脉内皮细胞（HUVEC）通过途径依赖于激活p38丝裂原活化蛋白激酶（p38 MAPK）和Akt，并刺激血管内皮生长因子受体2（VEGFR 2）的Tyr 1175的快速磷酸化。特异性瘦素受体拮抗剂可阻断瘦素诱导的VEGFR 2、p38 MAPK和Akt的磷酸化以及考克斯-2的诱导。考克斯-2、磷脂酰肌醇3-激酶（PI 3 K）/Akt通路和p38 MAPK的药理学抑制剂消除瘦素诱导的EC增殖（通过定量5-溴-2 ′-脱氧尿苷掺入、钙黄绿素荧光和碘化丙啶染色评估），减缓瘦素刺激的细胞的增加的迁移速率（体外伤口愈合测定），并抑制瘦素诱导的HUVEC在Matrigel上的毛细血管样管形成。在鸡胚绒毛尿囊膜血管形成试验中，抑制VEGFR 2酪氨酸激酶活性可降低瘦素刺激的p38 MAPK和Akt激活、考克斯-2诱导和促血管生成EC反应，阻断VEGFR 2或考克斯-2活性可消除瘦素驱动的新生血管形成。我们的结论是一个功能性的内皮细胞p38 MAPK/Akt/考克斯-2信号轴所需的瘦素的促血管生成的行动，这是调控上游的ObRb依赖性激活的VEGFR 2。这些研究确定了VEGFR 2作为瘦素刺激的考克斯-2表达和血管生成的介质的新功能，并且对于理解瘦素对非肥胖和肥胖个体中的脉管系统的调节具有意义。
The adipocyte-derived hormone leptin influences the behaviour of a wide range of cell types and is now recognised as a pro-angiogenic and pro-inflammatory factor. In the vasculature, these effects are mediated in part through its direct leptin receptor (ObRb)-driven actions on endothelial cells (ECs) but the mechanisms responsible for these activities have not been established. In this study we sought to more fully define the molecular links between inflammatory and angiogenic responses of leptin-stimulated human ECs. Immunoblotting studies showed that leptin increased cyclo-oxygenase-2 (COX-2) expression (but not COX-1) in cultured human umbilical vein ECs (HUVEC) through pathways that depend upon activation of both p38 mitogen-activated protein kinase (p38MAPK) and Akt, and stimulated rapid phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) on Tyr1175. Phosphorylation of VEGFR2, p38MAPK and Akt, and COX-2 induction in cells challenged with leptin were blocked by a specific leptin peptide receptor antagonist. Pharmacological inhibitors of COX-2, the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and p38MAPK abrogated leptin-induced EC proliferation (assessed by quantifying 5-bromo-2′-deoxyuridine incorporation, calcein fluorescence and propidium iodide staining), slowed the increased migration rate of leptin-stimulated cells (in vitro wound healing assay) and inhibited leptin-induced capillary-like tube formation by HUVEC on Matrigel. Inhibition of VEGFR2 tyrosine kinase activity reduced leptin-stimulated p38MAPK and Akt activation, COX-2 induction, and pro-angiogenic EC responses, and blockade of VEGFR2 or COX-2 activities abolished leptin-driven neo-angiogenesis in a chick chorioallantoic membrane vascularisation assay in vivo. We conclude that a functional endothelial p38MAPK/Akt/COX-2 signalling axis is required for leptin's pro-angiogenic actions and that this is regulated upstream by ObRb-dependent activation of VEGFR2. These studies identify a new function for VEGFR2 as a mediator of leptin-stimulated COX-2 expression and angiogenesis and have implications for understanding leptin's regulation of the vasculature in both non-obese and obese individuals.
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影响因子：
4.8
作者：
Gonzalez-Perez RR;Xu Y;Guo S;Watters A;Zhou W;Leibovich SJ
通讯作者：
Leibovich SJ
影响因子：
4.9
作者：
Artwohl, M;Roden, M;Baumgartner-Parzer, SM
通讯作者：
Baumgartner-Parzer, SM
影响因子：
4.8
作者：
Lewthwaite, JC;Bastow, ER;Pitsillides, AA
通讯作者：
Pitsillides, AA
影响因子：
8.3
作者：
Goetze, S;Bungenstock, A;Gräfe, M
通讯作者：
Gräfe, M
影响因子：
20.1
作者：
Bouloumié, A;Drexler, HCA;Busse, R
通讯作者：
Busse, R