Cobalt chloride-induced signaling in endothelium leading to the augmented adherence of sickle red blood cells and transendothelial migration of monocyte-like HL-60 cells is blocked by PAF-receptor antagonist.

Sultana C; Shen Y; Johnson CKalra VK

摘要

In response to hypoxia, sickle red blood cells (SS RBC) and leukocytes exhibit increased adherence to the vascular endothelium, while diapedesis of leukocytes through the blood vessel increases. However, the cellular signaling pathway(s) caused by hypoxia is poorly understood. We utilized CoCl2 as a mimetic molecule for hypoxia to study cellular signaling pathways. We found that in human umbilical vein endothelial cells (HUVEC), CoCl2 at 2 mM concentration induced the surface expression of a subset of CAMs (VCAM-1) and activation of transcription factor NF-kappaB in the nuclear extracts of HUVEC. Furthermore, CoCl2 also caused time-dependent tyrosine phosphorylation of mitogen-activated protein (MAP) kinase isoform ERK2 without significantly affecting ERK1, indicating ERK2 is the preferred substrate for upstream kinase of the MAPK pathway. Inhibitors of MAP kinase (PD98059) or platelet-activating factor (PAF)- receptor antagonist (CV3988) inhibited the CoCl2-induced NF-kappaB activation and VCAM-1 expression. Augmented expression of VCAM-1 led to increased SS RBC adhesion, inhibitable by a VCAM-1 antibody. Additionally, CoCl2 caused a two- to threefold increase in the rate of transendothelial migration of monocyte-like HL-60 cells and a twentyfold increase in phosphorylation of platelet endothelial cell adhesion molecules (PECAM-1). The transendothelial migration of monocytes was inhibited by an antibody to PECAM-1. Both phosphorylation of PECAM-1 and transendothelial migration of monocytes in response to CoCl2 were inhibited by protein kinase inhibitor (GF109203X) and augmented by protein phosphatase inhibitor (Calyculin A). Our data suggests that CoCl2-induced cellular signals directing increased expression of VCAM-1 in HUVEC involve downstream activation of MAP kinase and NF-kappaB, while the phosphorylation of PECAM-1 occurs as a result of activation of PKC. We conclude that PAF-receptor antagonist inhibits the CoCl2- or hypoxia-induced increase in the adhesion of SS RBC, PECAM-1 phosphorylation, and the concomitant transendothelial migration of monocytes.

机译：为了应对缺氧,镰状红细胞(党卫军加拿大皇家银行)和白细胞展览增加依从性血管内皮,血球渗出通过血管增加白细胞。然而,细胞信号通路引起的缺氧是知之甚少。CoCl2作为缺氧的分子模拟研究细胞信号通路。人类脐静脉内皮细胞(HUVEC),在2毫米CoCl2浓度诱导表面的摄像头(VCAM-1)的一个子集激活的转录因子NF-kappaBHUVEC的核提取物。还导致时间酪氨酸磷酸化的增殖作用(MAP)激酶同种型ERK2不显著影响ERK1,表明ERK2是首选衬底为上游MAPK激酶途径。platelet-activating因子(PAF)参谋长-受体拮抗剂(CV3988)抑制CoCl2-inducedNF-kappaB激活和VCAM-1表达式。增强表达VCAM-1导致增加党卫军红细胞粘附,VCAM-1的制约抗体三倍的速度增加transendothelial迁移monocyte-like HL-60细胞和二十倍的增加血小板内皮细胞磷酸化粘附分子(PECAM-1)。transendothelial单核细胞迁移抑制抗体PECAM-1。磷酸化PECAM-1 transendothelial单核细胞迁移在回应CoCl2抑制蛋白激酶抑制剂(GF109203X)和增强蛋白质磷酸酶抑制剂(Calyculin)。我们的数据表明CoCl2-induced细胞信号指挥增加在HUVEC VCAM-1涉及的表达式下游MAP激酶激活和NF-kappaB, PECAM-1的磷酸化由于激活PKC发生。得出结论:PAF-receptor拮抗剂抑制CoCl2 -或低氧诱导增加红细胞粘附的党卫军,PECAM-1磷酸化随之而来的transendothelial迁移单核细胞。

Cobalt chloride-induced signaling in endothelium leading to the augmented adherence of sickle red blood cells and transendothelial migration of monocyte-like HL-60 cells is blocked by PAF-receptor antagonist.

摘要

著录项

相似文献

相关主题

期刊订阅