Zinc attenuates tumor necrosis factor-mediated activation of transcription factors in endothelial cells
Zinc attenuates tumor necrosis factor-mediated activation of transcription factors in endothelial cells
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DOI：
10.1080/07315724.1997.10718706
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发表时间：
1997-10-01
影响因子：
3.5
通讯作者：
Hennig, B
中科院分区：
文献类型：
--
作者：
Connell, P;Young, VM;Hennig, B
目的：本研究的目的是验证锌可以通过干扰氧化应激介导的细胞信号传导和随后抑制内皮细胞炎症反应来保护内皮功能障碍的假设。我们的方法是比较锌缺乏条件下内皮屏障功能在分子和生化水平上的改变。方法：为了验证我们的假设，内皮细胞暴露在缺锌培养基中2至10天，以耗尽细胞中的锌储存。在此之后，一半的组补充锌（9.2 μ M） 48小时。另一半作为缺锌对照组。然后用肿瘤坏死因子- α (TNF)对这些细胞进行不同时间的刺激。从细胞中提取核提取物，分析核因子KB （NF-kappa B）和激活蛋白1 （AP-1）的结合。分析细胞培养基中白细胞介素8 （IL-8）的产生，并测定细胞蛋白。结果：锌补充剂导致细胞锌含量增加74%。研究还表明，暴露于TNF （100 U/mL培养基）1.5小时显著增加NF-kappa B和AP-1的结合，当细胞补充生理水平的锌时，这种结合明显降低。补充锌还引起内皮细胞对tnf介导的细胞活化的IL-8表达的显著衰减。讨论：我们之前的数据清楚地表明锌是维持内皮完整性的保护性和关键营养素。目前的数据表明，锌可以防止细胞因子介导的氧化应激敏感转录因子的激活，炎症细胞因子的上调和内皮细胞功能障碍。这可能有助于理解动脉粥样硬化的机制。
Objective: The objective of the study was to test the hypothesis that zinc can protect against endothelial dysfunction by interfering with oxidative stress-mediated cellular signaling and subsequent inhibition of an endothelial cell inflammatory response. Our approach was to compare alterations on molecular and biochemical levels with changes in endothelial barrier function that occur in zinc deficient conditions.Methods: To investigate our hypothesis, endothelial cells were exposed to zinc deficient media for 2 to 10 days to deplete cellular zinc stores. Following this, half of the groups received zinc supplementation (9.2 mu M) for 48 hours. The other half served as zinc deficient controls. These cells were then challenged with tumor necrosis factor-alpha (TNF) for varying time periods. Nuclear extracts were prepared from cells and analyzed for nuclear factor KB (NF-kappa B) and activator protein-1 (AP-1) binding. Media from cells were analyzed for interleukin 8 (IL-8) production, and cellular proteins were determined.Results: Zinc supplementation resulted in a 74% increase in cellular zinc content. It was also shown that a 1.5 hour exposure to TNF (100 U/mL medium) significantly increased NF-kappa B and AP-1 binding, which was lowered considerably when cells were supplemented with physiological levels of zinc. Zinc supplementation also caused a marked attenuation in IL-8 expression by endothelial cells in response to TNF-mediated cell activation.Discussion: Our previous data clearly show that zinc is a protective and critical nutrient for maintenance of endothelial integrity. The present data suggest that zinc may protect against cytokine-mediated activation of oxidative stress sensitive transcription factors, upregulation of inflammatory cytokines and endothelial cell dysfunction. This may have implications in understanding mechanisms of atherosclerosis.