Nox4 NADPH oxidase mediates oxidative stress and apoptosis caused by TNF-α in cerebral vascular endothelial cells
Nox4 NADPH oxidase mediates oxidative stress and apoptosis caused by TNF-α in cerebral vascular endothelial cells
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DOI：
10.1152/ajpcell.00381.2008
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发表时间：
2009-03-01
影响因子：
5.5
通讯作者：
Parfenova, Helena
中科院分区：
文献类型：
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作者：
Basuroy, Shyamali;Bhattacharya, Sujoy;Parfenova, Helena
Basuroy S、Bhattacharya S、Leffler CW、Parfenova H。 Nox4 NADPH 氧化酶介导脑血管内皮细胞中 TNF-α 引起的氧化应激和细胞凋亡。 Am J Physiol Cell Physiol 296：C422-C432，2009。首次发表于 2008 年 12 月 31 日； doi:10.1152/ajpcell.00381.2008.-炎症性脑病可能会损害脑血管内皮，导致脑血流失调。促炎细胞因子 TNF-α 会引起新生猪脑微血管内皮细胞 (CMVEC) 的氧化应激和凋亡。我们研究了活性氧的主要细胞来源对内皮炎症反应的贡献。一氧化氮合酶和黄嘌呤氧化酶抑制剂（N-omega-硝基-L-精氨酸和别嘌呤醇）没有效果，而线粒体电子传递抑制剂（CCCP、2-噻吩酰三氟丙酮和鱼藤酮）则减弱 TNF-α 诱导的超氧化物（O2（中心点-））和细胞凋亡。 NADPH 氧化酶抑制剂（二亚苯基碘和罗布麻素）大大减少了 TNF-α 诱发的 O2（中心点-）生成和细胞凋亡。 TNF-α 迅速增加 CMVEC 中的 NADPH 氧化酶活性。 Nox4 是 NADPH 氧化酶的细胞特异性催化亚基，在 CMVEC 中高度表达，有助于基础 O2（中心点-）的产生，并导致响应 TNF-α 的氧化应激爆发。 Nox4 小干扰 RNA（而非 Nox2）的敲低可防止 CMVEC 中 TNF-α 引起的氧化应激和细胞凋亡。 Nox4 与 HO-2 共定位，HO-2 是血红素加氧酶 (HO) 的组成型亚型，对于内皮保护免受 TNF-α 毒性至关重要。 HO活性、胆红素和一氧化碳（CO，作为CO释放分子，CORM-A1）的产物，抑制Nox4产生的O2（中心点-）和TNF-α刺激引起的细胞凋亡。我们得出结论，Nox4 是炎症和 TNF-α 诱导的氧化应激导致脑内皮细胞凋亡的主要来源。 CO 和胆红素通过抑制 Nox4 活性和/或通过 O2（中心点-）清除来对抗 TNF-α 诱导的氧化应激的能力，再加上脑血管内皮细胞中 HO-2 和 Nox4 的紧密细胞内区室化，可能有助于 HO-2 对炎症性脑血管疾病的细胞保护作用。
Basuroy S, Bhattacharya S, Leffler CW, Parfenova H. Nox4 NADPH oxidase mediates oxidative stress and apoptosis caused by TNF-alpha in cerebral vascular endothelial cells. Am J Physiol Cell Physiol 296: C422-C432, 2009. First published December 31, 2008; doi:10.1152/ajpcell.00381.2008.-Inflammatory brain disease may damage cerebral vascular endothelium leading to cerebral blood flow dysregulation. The proinflammatory cytokine TNF-alpha causes oxidative stress and apoptosis in cerebral microvascular endothelial cells (CMVEC) from newborn pigs. We investigated contribution of major cellular sources of reactive oxygen species to endothelial inflammatory response. Nitric oxide synthase and xanthine oxidase inhibitors (N-omega-nitro-L-arginine and allopurinol) had no effect, while mitochondrial electron transport inhibitors (CCCP, 2-thenoyltrifluoroacetone, and rotenone) attenuated TNF-alpha-induced superoxide (O2(center dot-)) and apoptosis. NADPH oxidase inhibitors (diphenylene iodonium and apocynin) greatly reduced TNF-alpha-evoked O2(center dot-) generation and apoptosis. TNF-alpha rapidly increased NADPH oxidase activity in CMVEC. Nox4, the cell-specific catalytic subunit of NADPH oxidase, is highly expressed in CMVEC, contributes to basal O2(center dot-) production, and accounts for a burst of oxidative stress in response to TNF-alpha. Nox4 small interfering RNA, but not Nox2, knockdown prevented oxidative stress and apoptosis caused by TNF-alpha in CMVEC. Nox4 is colocalized with HO-2, the constitutive isoform of heme oxygenase (HO), which is critical for endothelial protection against TNF-alpha toxicity. The products of HO activity, bilirubin and carbon monoxide (CO, as a CO-releasing molecule, CORM-A1), inhibited Nox4-generated O2(center dot-) and apoptosis caused by TNF-alpha stimulation. We conclude that Nox4 is the primary source of inflammation-and TNF-alpha-induced oxidative stress leading to apoptosis in brain endothelial cells. The ability of CO and bilirubin to combat TNF-alpha-induced oxidative stress by inhibiting Nox4 activity and/or by O2(center dot-) scavenging, taken together with close intracellular compartmentalization of HO-2 and Nox4 in cerebral vascular endothelium, may contribute to HO-2 cytoprotection against inflammatory cerebrovascular disease.