Department of Pediatrics (Cardiology), University of Washington, Seattle, Wash; Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute, Seattle, Wash.
Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute, Seattle, Wash.
J Thorac Cardiovasc Surg. 2019 Sep;158(3):882-890.e4. doi: 10.1016/j.jtcvs.2019.02.091. Epub 2019 Mar 6.
Brain injury, leading to long-term neurodevelopmental deficits, is a major complication in neonates undergoing cardiac surgeries. Because the striatum is one of the most vulnerable brain regions, we used mRNA sequencing to unbiasedly identify transcriptional changes in the striatum after cardiopulmonary bypass and associated deep hypothermic circulatory arrest.
Piglets were subjected to cardiopulmonary bypass with deep hypothermic circulatory arrest at 18°C for 30 minutes and then recovered for 6 hours. mRNA sequencing was performed to compare changes in gene expression between the striatums of sham control and deep hypothermic circulatory arrest brains.
We found 124 significantly upregulated genes and 74 significantly downregulated genes in the striatums of the deep hypothermic circulatory arrest group compared with the sham controls. Pathway enrichment analysis demonstrated that inflammation and apoptosis were the strongest pathways activated after surgery. Chemokines CXCL9, CXCL10, and CCL2 were the top upregulated genes with 32.4-fold, 22.2-fold, and 17.6-fold increased expression, respectively, in the deep hypothermic circulatory arrest group compared with sham controls. Concomitantly, genes involved in cell proliferation, cell-cell adhesion, and structural integrity were significantly downregulated in the deep hypothermic circulatory arrest group. Analysis of promoter regions of all upregulated genes revealed over-representation of nuclear factor-kB transcription factor binding sites.
Our study provides a comprehensive view of global transcriptional changes in the striatum after deep hypothermic circulatory arrest and found strong activation of both inflammatory and apoptotic signaling pathways in the deep hypothermic circulatory arrest group. Nuclear factor-kB, a key driver of inflammation, appears to be an upstream regulator of the majority of the upregulated genes; hence, nuclear factor-kB inhibitors could potentially be tested for beneficial effects on neurologic outcome.
脑损伤导致长期神经发育缺陷，是接受心脏手术的新生儿的主要并发症。由于纹状体是最脆弱的大脑区域之一，我们使用 mRNA 测序来 unbiasedly 鉴定体外循环后纹状体的转录变化，并与深低温循环停止相关联。
小猪在 18°C 下进行心肺旁路和深低温循环停止 30 分钟，然后恢复 6 小时。进行 mRNA 测序，以比较假手术对照和深低温循环停止大脑纹状体之间基因表达的变化。
我们发现深低温循环停止组纹状体中有 124 个显著上调基因和 74 个显著下调基因，与假手术对照组相比。通路富集分析表明，炎症和细胞凋亡是手术后激活的最强通路。趋化因子 CXCL9、CXCL10 和 CCL2 是上调最明显的基因，深低温循环停止组的表达分别增加了 32.4 倍、22.2 倍和 17.6 倍，与假手术对照组相比。同时，深低温循环停止组中参与细胞增殖、细胞-细胞粘附和结构完整性的基因显著下调。对所有上调基因的启动子区域进行分析表明，核因子-kB 转录因子结合位点过度表达。
我们的研究提供了深低温循环停止后纹状体全局转录变化的综合视图，并发现深低温循环停止组中炎症和细胞凋亡信号通路的强烈激活。核因子-kB，炎症的关键驱动因素，似乎是大多数上调基因的上游调节剂; 因此，核因子-kB 抑制剂可能被测试对神经功能结果的有益影响。
