Nephrology Research Group, Queen’s University Belfast, UK.
Epigenetics. 2010 Jul 1;5(5):396-401. doi: 10.4161/epi.5.5.12077.
We have previously identified differentially expressed genes in cell models of diabetic nephropathy and renal biopsies. Here we have performed quantitative DNA methylation profiling in cell models of diabetic nephropathy. Over 3,000 CpG units in the promoter regions of 192 candidate genes were assessed in unstimulated human mesangial cells (HMCs) and proximal tubular epithelial cells (PTCs) compared to HMCs or PTCs exposed to appropriate stimuli. A total of 301 CpG units across 38 genes (~20%) were identified as differentially methylated in unstimulated HMCs versus PTCs. Analysis of amplicon methylation values in unstimulated versus stimulated cell models failed to demonstrate a >20% difference between amplicons. In conclusion, our results demonstrate that (1) specific DNA methylation signatures are present in HMCs and PTCs, and (2) standard protocols for exposure of renal cells to stimuli that alter gene expression may be insufficient to replicate possible alterations in DNA methylation profiles in diabetic nephropathy.
我们之前已经在糖尿病肾病的细胞模型和肾活检中鉴定出差异表达的基因。在这里，我们在糖尿病肾病的细胞模型中进行了定量 DNA 甲基化分析。在未受刺激的人肾小球系膜细胞 (HMC) 和近端肾小管上皮细胞 (PTC) 中，对 192 个候选基因的启动子区域中的 3000 多个 CpG 单位进行了评估，与暴露于适当刺激物的 HMC 或 PTC 进行了比较。在未受刺激的 HMC 与 PTC 之间，有 38 个基因 (~20%)的 301 个 CpG 单位被鉴定为甲基化差异。对未受刺激与刺激细胞模型中扩增子甲基化值的分析未能证明扩增子之间存在 >20%的差异。总之，我们的结果表明：(1)HMC 和 PTC 中存在特定的 DNA 甲基化特征，(2)用于改变基因表达的肾细胞暴露于刺激物的标准方案可能不足以复制糖尿病肾病中 DNA 甲基化谱的可能变化。
