Department of Pharmacology & Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA.
J Mol Cell Cardiol. 2010 Oct;49(4):664-72. doi: 10.1016/j.yjmcc.2010.07.001. Epub 2010 Jul 16.
It has been shown that the transcription factor NF-kappaB is necessary for late phase cardioprotection after ischemic preconditioning (IPC) in the heart, and yet is injurious after ischemia/reperfusion (I/R). However the downstream gene expression programs that underlie the contribution of NF-kappaB to cardioprotection after late IPC are incompletely understood. The objective of this study was to delineate the specific genes that are regulated by NF-kappaB immediately after a late IPC stimulus and validate the methodology for the identification of NF-kappaB-dependent genes that contribute to cardioprotection. A directed microarray analysis identified 238 genes as up or downregulated in an NF-kappaB-dependent manner 3.5h after late IPC. Among these are several genes previously implicated in late IPC. Gene ontological analysis showed that the most significant group of NF-kappaB-dependent genes are heat shock response genes, including the genes encoding Hsp70.1 and Hsp70.3. Though an Hsp70.1/70.3 double knockout failed to exhibit cardioprotection, late IPC was intact in the Hsp70.1 single knockout. After I/R, the Hsp70.1/70.3 double knockout and the Hsp70.1 single knockout had significantly increased and reduced infarct size, respectively. These results delineate the immediate NF-kappaB-dependent transcriptome after late IPC. One of the major categories of NF-kappaB-dependent genes induced by late IPC is the heat shock response. The results of infarct studies confirm that Hsp70.3 is protective after IPC. However, though Hsp70.1 and Hsp70.3 are coordinately regulated, their functions are opposing after I/R injury.
已经表明，转录因子 NF-κB 是缺血预处理（IPC）后心脏晚期保护所必需的，但在缺血/再灌注（I/R）后是有害的。然而，NF-κB 对晚期 IPC 后心脏保护作用的下游基因表达程序尚未完全了解。本研究的目的是描绘 NF-κB 在晚期 IPC 刺激后立即调控的特定基因，并验证鉴定对心脏保护有贡献的 NF-κB 依赖性基因的方法。定向微阵列分析鉴定出 238 个基因在晚期 IPC 后 3.5 小时以 NF-κB 依赖性方式上调或下调。其中有几个基因以前与晚期 IPC 有关。基因本体论分析表明，NF-κB 依赖性基因中最显著的一组是热休克反应基因，包括编码 Hsp70.1 和 Hsp70.3 的基因。尽管 Hsp70.1/70.3 双敲除小鼠未能表现出心脏保护作用，但 Hsp70.1 单敲除小鼠的晚期 IPC 仍然完整。在 I/R 后，Hsp70.1/70.3 双敲除和 Hsp70.1 单敲除小鼠的梗死面积分别显著增加和减少。这些结果描绘了晚期 IPC 后立即发生的 NF-κB 依赖性转录组。晚期 IPC 诱导的 NF-κB 依赖性基因的主要类别之一是热休克反应。梗死研究的结果证实，Hsp70.3 在 IPC 后具有保护作用。然而，尽管 Hsp70.1 和 Hsp70.3 协同调节，但它们在 I/R 损伤后的功能是相反的。
