糖皮质激素反应性的表观遗传学编程和免疫性损伤性肾炎的关系

项目名称： 糖皮质激素反应性的表观遗传学编程和免疫性损伤性肾炎的关系

项目编号： No.81072490

项目类型： 面上项目

立项/批准年度： 2011

项目学科： 轻工业、手工业

项目作者： 姜傥

作者单位： 中山大学

项目金额： 10万元

中文摘要： 为了研究激素治疗所引发的糖皮质激素抵抗现象的内在机制，我们通过长期(大于2周)，高浓度(10-6M)地塞米松刺激的方法，建立了一种激素抵抗细胞模型，并用流式细胞仪检测细胞对激素诱导凋亡的抵抗能力的方法进行验证。我们尝试过的细胞系包括U937、A549及Hela。细胞模型建立成功之后，我们用RT-PCR的方法测定了对照(激素敏感）及激素抵抗细胞的GR、GRα12289;GRβ12289;GRP、1D、1J、1E、1F、1C、1H的mRNA表达水平。于此同时，用MassArray的方法对两组细胞的DNA甲基化水平进行检测。U937细胞中建立失败，但在A549细胞系及Hela细胞系中取得成功。mRNA分析发现，与对照组相比，激素抵抗组细胞的GR、GRα12289;GRβ12289;GRP及外显子1J、1B、1C、1H的表达水平下降，其余第一外显子未检出。NR3C1基因的CpG岛平均甲基化水平在5%以下。除启动子1F外，抵抗细胞所有测得启动子序列的甲基化水平均高于对照组。由于CpG位点过于密集，无法设计出启动子1C及1H序列的扩增引物。但因其mRNA水平下降，我们高度怀疑二者同样呈高甲基化状态。

中文关键词： DNA甲基化；表观遗传学；糖皮质激素抵抗；NR3C1

英文摘要： In order to study the mechanism of glucocorticoid treatment induced glucocorticoid resistance(GR), we created an cell model by long time(over 2 weeks), high concentration(10-6 M) dexamethasone treatment，and tested by flow cytometry apotosis analysis.We tried several three different cell lines :U937,A549， Hela.Once the model were successfully made,the he mRNA levels of GR， GRα65292;GRβ65292;GRP and exon 1D，1J，1E，1B，1F，1C，1H in both the negative control cell and the glucocorticoid resistant cell were measured by RT-PCR technology. DNA methylation levels of both sides were analyzed at the same time using MassArray method. After 6 months dexamethasone treatment, the apotosis rate of U937 remain the same, failed to establish the GR model. But we successfully created the A549 and Hela cells GR model.The mRNA level of GR,all three GR subtypes and exon 1J,1B,1C,1H were decreased, other types of first exons were not detected in both the control cells and resistant cells.The average Methylation levels of the NR3C1 gene CpG island were below 5%. All of the Glucocorticoid resistant Cell promoters' methylaion level is higher than those of the control cell,excepet promoter 1F.Due to the high density of CpG site , we couldn't find any primers to amplify the sequence of the promoter 1C and 1H.But since the mRNA levels of those exons were down regulated, we highly suspect that the promoter 1C and 1H were also hypermethylated.

英文关键词： DNA methylation;Epigenetic;Glucocorticoid;NR3C1