Department of Pulmonary and Critical Care Medicine, the Second Affiliated Hospital of Fujian Medical University, Respirology Medicine Centre of Fujian Province, Quanzhou, China.
Department of Infectious Disease, General Hospital of Southern Theater Command, PLA, Guangzhou, China.
BMC Pulm Med. 2021 Mar 23;21(1):98. doi: 10.1186/s12890-021-01464-z.
Acute lung injury (ALI) is characterized by inflammation and oxidative stress. Nuclear factor-kappaB (NF-κB) mediates the expression of various inflammation-related genes, including the NADPH oxidase family. This study aimed to identify the potential regulatory role of NF-κB on NADPH oxidases in tumor necrosis factor-α (TNF-α)-induced oxidative stress in human alveolar epithelial cells.
A549 cells were treated with TNF-α for 24 h to establish ALI cell models. RT-PCR, western blot, assessment of oxidative stress, Alibaba 2.1 online analysis, electrophoretic mobility shift assays and luciferase reporter analysis were employed to identify the potential regulatory role of NF-κB on NADPH oxidases in TNF-α-induced oxidative stress in human alveolar epithelial cells.
The expression of NF-κB/p65 was notably upregulated in TNF-α-stimulated A549 cells. NF-κB knockdown by siRNA significantly inhibited the TNF-α-induced oxidative stress. Moreover, NF-κB/p65 siRNA could inhibit the activation of NOX1, NOX2 and NOX4 mRNA and protein expression in TNF-α-stimulated A549 cells. The next study demonstrated that NF-κB activated the transcription of NOX1 by binding to the -261 to -252 bp (NOX1/κB2, TAAAAATCCC) region of NOX1 promoter in TNF-α-stimulated A549 cells.
Our data demonstrated that NF-κB can aggravate TNF-α-induced ALI by regulating the oxidative stress response and the expression of NOX1, NOX2 and NOX4. Moreover, NF-κB could promote the NOX1 transcriptional activity via binding its promoter in TNF-α-stimulated A549 cells.
急性肺损伤（ALI）的特征为炎症和氧化应激。核因子-κB（NF-κB）介导各种炎症相关基因的表达，包括 NADPH 氧化酶家族。本研究旨在确定 NF-κB 在肿瘤坏死因子-α（TNF-α）诱导的人肺泡上皮细胞氧化应激中对 NADPH 氧化酶的潜在调节作用。
用 TNF-α处理 A549 细胞 24 h 建立 ALI 细胞模型。采用 RT-PCR、western blot、氧化应激评估、Alibaba 2.1 在线分析、电泳迁移率变动分析和荧光素酶报告分析，鉴定 NF-κB 在 TNF-α诱导的人肺泡上皮细胞氧化应激中对 NADPH 氧化酶的潜在调节作用。
TNF-α刺激的 A549 细胞中 NF-κB/p65 的表达明显上调。siRNA 敲低 NF-κB 显著抑制 TNF-α诱导的氧化应激。此外，NF-κB/p65 siRNA 可抑制 TNF-α刺激的 A549 细胞中 NOX1、NOX2 和 NOX4 mRNA 和蛋白表达的激活。进一步的研究表明，NF-κB 通过与 TNF-α 刺激的 A549 细胞中 NOX1 启动子的-261 至-252 bp（NOX1/κB2，TAAAAATCCC）区域结合，激活 NOX1 的转录。
我们的数据表明，NF-κB 可以通过调节氧化应激反应和 NOX1、NOX2 和 NOX4 的表达来加重 TNF-α 诱导的 ALI。此外，NF-κB 可以通过与 TNF-α 刺激的 A549 细胞中 NOX1 启动子结合来促进其转录活性。
