Differential regulation of p90 ribosomal S6 kinase and big mitogen-activated protein kinase 1 by ischemia/reperfusion and oxidative stress in perfused guinea pig hearts.
Differential regulation of p90 ribosomal S6 kinase and big mitogen-activated protein kinase 1 by ischemia/reperfusion and oxidative stress in perfused guinea pig hearts.
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DOI：
10.1161/01.res.85.12.1164
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发表时间：
1999-12
影响因子：
20.1
通讯作者：
Y. Takeishi;J. Abe;Jiing-Dwan Lee;H. Kawakatsu;R. Walsh;B. Berk
中科院分区：
文献类型：
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作者：
Y. Takeishi;J. Abe;Jiing-Dwan Lee;H. Kawakatsu;R. Walsh;B. Berk
活性氧簇(ROS)激活了Src和丝裂原活化蛋白激酶超家族的成员，包括大丝裂原活化蛋白激酶1(BMK1)和细胞外信号调节蛋白激酶(ERK1/2)。ERK1/2的一个重要下游效应因子是p90核糖体S6激酶(P90RSK)，它通过激活多种转录因子和Na(+)/H(+)交换器在细胞生长中发挥重要作用。在此之前，我们已经证明了Src通过氧化还原敏感的信号通路来调节BMK1。由于ROS是在缺血和缺血后的再灌流过程中产生的，我们评估了这些刺激(H(2)O(2)、缺血和再灌流)对豚鼠灌流心脏ERK1/2、p90RSK、Src和BMK1激活的影响。H(2)O(2)(10 0微摩尔/L)可显著激活所有的酶活性。缺血单独刺激p90RSK、src和BMK1，但不激活ERK1/2。这些结果表明，p90RSK通过非ERK1/2途径被激活。src在缺血介导的bmk1激活中的作用是通过抑制src抑制剂4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3，4-d]pyrimidine.来实现的缺血再灌流刺激P90RSK和ERK1/2。相反，尽管ROS在缺血再灌流过程中升高，但BMK1及其上游调节因子Src的活性在缺血后再灌流后明显减弱。C-末端Src激酶在缺血时的激活，而在再灌流过程中不激活，表明再灌流对Src和BMK1活性的减弱不受C-末端Src激酶活性的调节。抗氧化剂N-2-硫代丙酰甘氨酸完全抑制再灌流诱导的ERK1/2和p90RSK的激活，但仅部分抑制缺血诱导的Src和BMK1的激活。本研究首次证明了缺血后再灌注对Src和BMK1的共同调节，我们认为这是通过一种新的、不依赖ROS的途径发生的。
Reactive oxygen species (ROS) activate members of the Src kinase and mitogen-activated protein kinase superfamily, including big mitogen-activated protein kinase 1 (BMK1) and extracellular signal-regulated kinases (ERK1/2). A potentially important downstream effector of ERK1/2 is p90 ribosomal S6 kinase (p90RSK), which plays an important role in cell growth through the activation of several transcription factors, as well as the Na(+)/H(+) exchanger. Previously, we showed that Src regulates BMK1 via a redox-sensitive signaling pathway. Because ROS are generated during ischemia and reperfusion after ischemia, we assessed the effects of these stimuli (H(2)O(2), ischemia, and reperfusion) in the activation of ERK1/2, p90RSK, Src, and BMK1 in perfused guinea pig hearts. H(2)O(2) (100 micromol/L) significantly activated all kinases. Ischemia alone stimulated p90RSK, Src, and BMK1 but not ERK1/2. These results suggest that p90RSK activation through ischemia occurs via a pathway other than ERK1/2. A role of Src in ischemia-mediated BMK1 activation was demonstrated through inhibition with the Src inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine. Reperfusion after ischemia stimulated both p90RSK and ERK1/2. In contrast, although ROS increase during reperfusion after ischemia, the activities of both BMK1 and its upstream regulator, Src, were markedly attenuated by reperfusion after ischemia. The activation of C-terminal Src kinase during ischemia but not during reperfusion suggests that the attenuation of Src and BMK1 activity by reperfusion was not regulated by C-terminal Src kinase activity. The antioxidant N-2-mercaptopropionylglycine completely inhibited ERK1/2 and p90RSK activation by reperfusion but only partially inhibited ischemia-induced Src and BMK1 activation. The present study is the first to show the coregulation of Src and BMK1 by reperfusion after ischemia, which we propose to occur via a novel, ROS-independent pathway.