Department of Neurosurgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Curr Neurovasc Res. 2020;17(5):534-628. doi: 10.2174/1567202617666201029145028.
The precise cellular behaviors of calcification, including its molecular and genetic activities, have not yet been fully established for carotid plaques.
We sought specific genes with tissue-specific differential methylation associated with carotid calcification status.
We classified eight plaques from carotid endarterectomy patients as high- or low-calcified based on their Agatston calcium scores. We analyzed differential DNA methylation and performed bioinformatics data mining.
A high correlation of average methylation levels (β-values) in promoter regions between high- and low-calcified plaque groups was observed. A principal component analysis of DNA methylation values in promoters of specimens revealed two independent clusters for high- and lowcalcified plaques. Volcano plots for methylation differences in promoter regions showed that significantly hypomethylated probes were more frequently found for high-calcified plaques than more methylated probes. Differential hypomethylation of receptor activity-modifying protein 1 (RAMP1) in high-calcified plaques was commonly extracted in both the promoter region and the cytosinephosphate- guanine (CpG) island shore region, where differential methylation had been reported to be more tissue-specific. Kyoto Encyclopedia of Genes and Genomes pathway analysis annotated a pathway associated with vascular smooth muscle contraction in the differentially methylated genes of the promoter and CpG island shore regions in high-calcified plaques.
Among the extracted differentially methylated genes, hypomethylated genes were more dominant than more methylated genes. The augmentation of RAMP1 by hypomethylation may contribute to the enhancement of anti-atherosclerotic effects and hence stability in high-calcified plaques. These results contribute to our understanding of the genetic signatures associated with calcification status and cellular activity in carotid plaques.
颈动脉斑块的钙化精确细胞行为，包括其分子和遗传活性，尚未完全确定。
我们旨在寻找与颈动脉钙化状态相关的具有组织特异性差异甲基化的特定基因。
我们根据 Agatston 钙评分将 8 个颈动脉内膜切除术患者的斑块分为高钙化成和低钙化成。我们分析了差异 DNA 甲基化并进行了生物信息学数据挖掘。
高钙化成和低钙化成斑块组的启动子区域平均甲基化水平（β 值）之间存在高度相关性。对标本启动子 DNA 甲基化值进行主成分分析，发现高钙化成和低钙化成斑块存在两个独立的簇。启动子区域甲基化差异的火山图显示，高钙化成斑块中更多的探针表现出显著的低甲基化，而不是更多的甲基化探针。在高钙化成斑块中，受体活性修饰蛋白 1（RAMP1）的差异低甲基化在启动子区域和胞嘧啶磷酸-鸟嘌呤（CpG）岛岸区普遍被提取出来，在那里已经报道了差异甲基化更具有组织特异性。京都基因与基因组百科全书通路分析注释了与血管平滑肌收缩相关的通路，该通路与高钙化成斑块中启动子和 CpG 岛岸区的差异甲基化基因有关。
在所提取的差异甲基化基因中，低甲基化基因比更多甲基化基因更为突出。RAMP1 的低甲基化可能有助于增强抗动脉粥样硬化作用，从而使高钙化成斑块更加稳定。这些结果有助于我们了解与颈动脉斑块钙化状态和细胞活性相关的遗传特征。
