Histamine increases sphingosine kinase-1 expression and activity in the human arterial endothelial cell line EA.hy 926 by a PKC-α-dependent mechanism
Histamine increases sphingosine kinase-1 expression and activity in the human arterial endothelial cell line EA.hy 926 by a PKC-α-dependent mechanism
复制标题
DOI：
10.1016/j.bbalip.2006.02.007
复制
发表时间：
2006-03-01
影响因子：
4.8
通讯作者：
Pfeilschifter, Josef
中科院分区：
文献类型：
--
作者：
Huwiler, Andrea;Doell, Frauke;Pfeilschifter, Josef
鞘氨醇1-磷酸（S1P）是鞘氨醇在鞘氨醇激酶（SKs）作用下产生的一种有效的有丝分裂信号。在这项研究中，我们发现在人动脉内皮细胞系EA.hy 926中，组胺诱导SK-1 mRNA和蛋白表达的时间依赖性上调，随后SK-1活性增加。直接蛋白激酶C激活剂12- o - tetradecanoylphorol -13-acetate （TPA）也观察到类似的SK-1上调。相比之下，SK-2活性不受组胺和TPA的影响。由于环己亚胺抑制了延迟的SK-1蛋白上调，SK-1蛋白表达的增加是由于刺激了重新合成。此外，SK-1 mRNA表达的增加是由组胺和TPA激活启动子增加引起的。在机制方面，SK-1的转录上调依赖于PKC和细胞外信号调节蛋白激酶（ERK）级联，因为staurosporine和MEK抑制剂U0126消除了tpa诱导的SK-1诱导。此外，组胺的作用被hi受体拮抗剂苯海拉明所消除，但不被h -2受体拮抗剂西咪替丁所消除。与SK-1的诱导平行，组胺和TPA刺激内皮细胞的迁移增加，这是通过小干扰RNA （siRNA）耗尽SK-1来阻止的。为了指定这种特定的细胞对特定PKC同工酶的反应，PKC- α， - δ和-epsilon的siRNA被用来选择性地下调各自的同工酶。有趣的是，只有pkc - α的缺失才会导致TPA和组胺触发的SK-1诱导和细胞迁移的完全丧失。总之，这些数据表明，通过组胺激活的h -1受体或直接PKC激活剂激活内皮细胞中的PKC-a可导致SK-1蛋白表达和活性的持续上调，而SK-1蛋白的表达和活性反过来又与内皮细胞迁移机制密切相关。(c) 2006 Elsevier B.V.版权所有
Sphingosine 1-phosphate (S1P) is a potent mitogenic signal generated from sphingosine by the action of sphingosine kinases (SKs). In this study, we show that in the human arterial endothelial cell line EA.hy 926 histamine induces a time-dependent upregulation of the SK-1 mRNA and protein expression which is followed by increased SK-1 activity. A similar upregulation of SK-1 is also observed with the direct protein kinase C activator 12-O-tetradecanoylphorbol-13-acetate (TPA). In contrast, SK-2 activity is not affected by neither histamine nor TPA. The increased SK-1 protein expression is due to stimulated de novo synthesis since cycloheximide inhibited the delayed SK-1 protein upregulation. Moreover, the increased SK-1 mRNA expression results from an increased promoter activation by histamine and TPA. In mechanistic terms, the transcriptional upregulation of SK-I is dependent on PKC and the extracellular signal-regulated protein kinase (ERK) cascade since staurosporine and the MEK inhibitor U0126 abolish the TPA-induced SK-1 induction. Furthermore, the histamine effect is abolished by the HI-receptor antagonist diphenhydramine, but not by the H-2-receptor antagonist cimetidine. Parallel to the induction of SK-1, histamine and TPA stimulate an increased migration of endothelial cells, which is prevented by depletion of the SK-1 by small interfering RNA (siRNA). To appoint this specific cell response to a specific PKC isoenzyme, siRNA of PKC-alpha, -delta, and -epsilon were used to selectively downregulate the respective isoforms. Interestingly, only depletion of PKC-alpha leads to a complete loss of TPA- and histamine-triggered SK-1 induction and cell migration. In summary, these data show that PKC-a activation in endothelial cells by histamine-activated H-1-receptors, or by direct PKC activators leads to a sustained upregulation of the SK-1 protein expression and activity which, in turn, is critically involved in the mechanism of endothelial cell migration. (c) 2006 Elsevier B.V. All rights reserved.