NG-monomethyl-L-arginine inhibits erythropoietin gene expression by stimulating GATA-2
NG-monomethyl-L-arginine inhibits erythropoietin gene expression by stimulating GATA-2
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DOI：
10.1182/blood.v96.5.1716.h8001716_1716_1722
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发表时间：
2000-09-01
期刊：
影响因子：
20.3
通讯作者：
Ozawa, K
中科院分区：
文献类型：
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作者：
Tarumoto, T;Imagawa, S;Ozawa, K
据报道，尿毒症患者的N-G-单甲基-L-精氨酸（L-NMMA）含量升高。基于L-NMMA对促红细胞生成素（Epo）基因转录因子的干扰可能是肾脏病贫血发病机制的假设，本研究旨在探讨L-NMMA通过加塔（GATA）转录因子对Epo基因表达的影响。L-NMMA引起Hep 3B细胞中Nc、环磷酸鸟苷（cGMP）和Epo蛋白水平降低。L-NAME（L-NMMA的类似物）也抑制贫血小鼠的Epo产生。将Epo启动子-荧光素酶基因转染Hep 3B细胞，发现L-NMMA抑制Epo启动子活性。然而，L-NMMA不抑制Epo启动子活性时，突变的Epo启动子（加塔TATA）转染，L-NMMA不影响增强子活性。电泳迁移率变动分析表明L-NMMA刺激加塔结合活性。L-NMMA对肝细胞核因子-4、COUP-TF 1、缺氧诱导因子-1和NF-κ B的结合活性无影响。cGMP可抑制L-NMMA诱导的加塔结合活性。L-NMMA还增加了加塔-2信使RNA的表达。这些结果表明，L-NMMA通过上调加塔转录因子抑制Epo基因表达，并支持L-NMMA是肾性贫血发病机制的候选物质之一的假设。(C)2000年，美国血液学会。
N-G-monomethyl-L-arginine (L-NMMA) has been reported to be elevated in uremic patients. Based on the hypothesis that the pathogenesis of the anemia of renal disease might be due to the perturbation of transcription factors of the erythropoietin (Epo) gene by L-NMMA, the present study was designed to investigate the effect of L-NMMA on Epo gene expression through the GATA transcription factor. L-NMMA caused decreased levels of Nc, cyclic guanosine monophosphate (cGMP), and Epo protein in Hep3B cells. L-NAME (analogue of L-NMMA) also inhibited Epo production in anemic mice. Transfection of the Epo promoter-luciferase gene into Hep3B cells revealed that L-NMMA inhibited the Epo promoter activity. However, L-NMMA did not inhibit the Epo promoter activity when mutated Epo promoter (GATA to TATA) was transfected, and L-NMMA did not affect the enhancer activity. Electrophoretic mobility shift assays demonstrated the stimulation of GATA binding activity by L-NMMA. However, L-NMMA had no effect on the binding activity of hepatic nuclear factor-4, COUP-TF1, hypoxia-inducing factor-1,or NF-kappa B, Furthermore, cGMP inhibited the L-NMMA-induced GATA binding activity. L-NMMA also increased GATA-2 messenger RNA expression. These results demonstrate that L-NMMA suppresses Epo gene expression by upregulation of the GATA transcription factor and support the hypothesis that L-NMMA is one of the candidate substances that underlie the pathogenesis of renal anemia. (C) 2000 by The American Society of Hematology.