Superoxide, H2O2, and iron are required for TNF-α-induced MCP-1 gene expression in endothelial cells:: role of Rac1 and NADPH oxidase
Superoxide, H2O2, and iron are required for TNF-α-induced MCP-1 gene expression in endothelial cells:: role of Rac1 and NADPH oxidase
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DOI：
10.1152/ajpheart.00716.2003
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发表时间：
2004-03-01
影响因子：
4.8
通讯作者：
Medford, RM
中科院分区：
文献类型：
--
作者：
Chen, XL;Zhang, Q;Medford, RM
活性氧（ROS）在单核细胞化学引诱蛋白(MCP)-1等炎症基因的表达中起着重要但尚未完全确定的作用。我们使用互补的分子和生化方法来探索特异性ROS的作用及其与内皮细胞炎症信号的分子联系。腺病毒介导的超氧化物歧化酶和过氧化氢酶的表达抑制了tnf α诱导的MCP-1基因表达，提示超氧化物（O-2（-环））和H2O2在MCP-1基因激活中起重要作用。此外，铁螯合剂1,2-二甲基-3-羟基吡啶-4- 1和羟基自由基清除剂二甲硫脲和二甲亚砜抑制tnf - α诱导的MCP-1表达，提示铁和羟基自由基在炎症信号激活中的重要作用。相比之下，5,10,15,20-四-（4-磺酰基）氯化铁（III）对过氧亚硝酸盐的清除作用对tnf - α诱导的MCP-1表达没有影响。二苯碘抑制NADPH氧化酶（负责O-2（-环）生成的主要氧化酶）可抑制tnf α诱导的MCP-1 mRNA积累。Rac1是NADPH氧化酶激活和O-2（-环）生成的上游信号分子。腺病毒表达显性阴性N17Rac1抑制tnf α诱导的MCP-1 mRNA水平和MCP-1蛋白分泌。N17Rac1的表达抑制了tnf α诱导的MCP-1和NF-kappaB的转录活性。这些数据表明，来自rac1激活的NADPH氧化酶的超氧化物和H2O2等ROS介导了内皮细胞中tnf - α诱导的MCP-1表达。
Reactive oxygen species (ROS) play an important but not yet fully defined role in the expression of inflammatory genes such as monocyte chemoattractant protein (MCP)-1. We used complementary molecular and biochemical approaches to explore the roles of specific ROS and their molecular linkage to inflammatory signaling in endothelial cells. Adenovirus-mediated expression of superoxide dismutase and catalase inhibited TNF-alpha-induced MCP-1 gene expression, suggesting important roles of superoxide (O-2(-circle)) and H2O2 in MCP-1 gene activation. In addition, the iron chelator 1,2-dimethyl-3-hydroxypyridin-4-one and the hydroxyl radical scavengers dimethylthiourea and dimethyl sulfoxide inhibited TNF-alpha-induced MCP-1 expression, suggesting important roles of iron and hydroxyl radicals in inflammatory signal activation. In contrast, scavenging of peroxynitrite with 5,10,15,20-tetrakis-(4-sulfonatophenyl) prophyrinato iron (III) chloride had no effect on TNF-alpha-induced MCP-1 expression. Inhibition of NADPH oxidase, the major oxidase responsible for O-2(-circle) generation, with diphenylene iodonium suppressed TNF-alpha-induced MCP-1 mRNA accumulation. Rac1 is an upstream signaling molecule for the activation of NADPH oxidase and O-2(-circle) generation. Expression of dominant negative N17Rac1 by adenovirus suppressed TNF-alpha-induced MCP-1 mRNA levels and MCP-1 protein secretion. Expression of N17Rac1 inhibited TNF-alpha-induced MCP-1 and NF-kappaB transcriptional activity. These data suggest that ROS such as superoxide and H2O2 derived from Rac1-activated NADPH oxidase mediate TNF-alpha-induced MCP-1 expression in endothelial cells.