Fifth Medical Department, University Hospital Mannheim, University of Heidelberg, 68167 Mannheim, Germany.
Free Radic Biol Med. 2012 Feb 15;52(4):794-802. doi: 10.1016/j.freeradbiomed.2011.11.035. Epub 2011 Dec 21.
Carbon monoxide (CO) abrogates TNF-α-mediated inflammatory responses in endothelial cells, yet the underlying mechanism thereof is still elusive. We have previously shown that the anti-inflammatory effect of CO-releasing molecule-3 (CORM-3) is not completely mediated via deactivation of the NF-κB pathway. In this study, we sought to explore other potential mechanisms by which CORM-3 downregulates VCAM-1 expression on TNF-α-stimulated HUVECs. By genome-wide gene expression profiling and pathway analysis we studied the relevance of particular pathways for the anti-inflammatory effect of CORM-3. In CORM-3-stimulated HUVECs significant changes in expression were found for genes implicated in the proteasome and porphyrin pathways. Although proteasome activities were increased by CORM-3, proteasome inhibitors did not abolish the effect of CORM-3. Likewise, heme oxygenase-1 inhibitors did not abrogate the ability of CORM-3 to downregulate VCAM-1 expression. Interestingly, CORM-3 inhibited MAPK p38, and the p38 inhibitor SB203580 downregulated VCAM-1 expression. However, downregulation of VCAM-1 by CORM-3 occurred only at concentrations that partly inhibit ATP production and sodium azide and oligomycin paralleled the effect of CORM-3 in this regard. Our results indicate that CORM-3-induced downregulation of VCAM-1 is mediated via p38 inhibition and mitochondrial respiration, whereas the ubiquitin-proteasome system seems not to be involved.
一氧化碳（CO）可阻断内皮细胞中 TNF-α 介导的炎症反应，但其中的机制仍不清楚。我们之前的研究表明，CO 释放分子-3（CORM-3）的抗炎作用并非完全通过 NF-κB 通路的失活来介导。在本研究中，我们试图探索 CORM-3 下调 TNF-α 刺激的 HUVECs 中 VCAM-1 表达的其他潜在机制。通过全基因组基因表达谱分析和通路分析，我们研究了特定通路与 CORM-3 的抗炎作用的相关性。在 CORM-3 刺激的 HUVECs 中，与蛋白酶体和卟啉途径相关的基因表达发生了显著变化。尽管 CORM-3 增加了蛋白酶体的活性，但蛋白酶体抑制剂并不能消除 CORM-3 的作用。同样，血红素加氧酶-1 抑制剂也不能阻断 CORM-3 下调 VCAM-1 表达的能力。有趣的是，CORM-3 抑制了 MAPK p38，而 p38 抑制剂 SB203580 下调了 VCAM-1 的表达。然而，CORM-3 下调 VCAM-1 仅发生在部分抑制 ATP 产生的浓度下，且叠氮钠和寡霉素在这方面与 CORM-3 的作用相似。我们的结果表明，CORM-3 诱导的 VCAM-1 下调是通过 p38 抑制和线粒体呼吸介导的，而泛素-蛋白酶体系统似乎不参与其中。
