Hif1α down-regulation is associated with transposition of great arteries in mice treated with a retinoic acid antagonist
Hif1α down-regulation is associated with transposition of great arteries in mice treated with a retinoic acid antagonist
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DOI：
10.1186/1471-2164-11-497
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发表时间：
2010-09-16
期刊：
影响因子：
4.4
通讯作者：
Novelli, Giuseppe
中科院分区：
文献类型：
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作者：
Amati, Francesca;Diano, Laura;Novelli, Giuseppe
背景：先天性心脏病 (CHD) 占所有人类先天性畸形的 25%。然而，迄今为止，已知的导致冠心病的基因还很少。心脏发育的分子和遗传分析是鉴定其突变可能与人类冠心病相关的重要心脏调节因子的一种有前景的方法。通过使用三重视黄酸竞争性拮抗剂 (BMS189453)，我们之前开发了先天性心脏缺陷 (81%)、胸腺异常 (98%) 和神经管缺陷 (20%) 的小鼠模型。 D-TGA（D 型大动脉转位）是观察到的最常见的心脏缺陷 (61%)。最近，我们通过口服叶酸 (FA) 能够部分挽救这种异常表型（CHD 降低至 64.8%，p = 0.05）。现在，我们在小鼠模型中进行了微阵列分析，以发现可能与该 CHD 发病机制有关的基因/转录本。结果：我们通过微阵列和 qRT-PCR 分析了单独使用 BMS189453 和使用 BMS189453 加叶酸 (FA) 处理的小鼠胚胎 (8.5 dpc)。通过选择倍数变化 (FC) >= +/- 1.5，我们检测到 447 个基因在 BMS 处理的胚胎与未处理的对照胚胎中存在差异表达，而 239 个基因在 BMS 处理的胚胎（其母亲也接受 FA 补充）与 BMS 处理的胚胎相比存在差异表达。在微阵列和qRT-PCR结果的基础上，我们进一步分析了Hif1α基因。事实上，与未处理的对照相比，BMS 处理的胚胎中 Hif1 α 下调（FCmicro = -1.79；FCqRT-PCR = -1.76；p = 0.005），并且与 BMS 处理的胚胎相比，BMS+FA 处理的胚胎中其表达水平增加（FCmicro = +1.17；FCqRT-PCR = +1.28：p = 0.005）。免疫荧光实验证实，与未处理和 BMS+FA 处理的胚胎相比，BMS 处理的胚胎中 Hif1 α 蛋白表达不足，此外，我们证明在 8.5 dpc 时，Hif1 α 主要在胚胎心脏区域表达。结论：我们提出 Hif1 α 下调是对阻断视黄酸的反应。 结合可能导致小鼠新生儿心脏缺陷的发生。与我们的假设一致，当 Hif1a 表达水平恢复（通过补充叶酸）时，CHD 会减少。据我们所知，这是第一份将视黄酸代谢与 Hif1 α 调节和 D-TGA 发展联系起来的报告。
Background: Congenital heart defect (CHD) account for 25% of all human congenital abnormalities. However, very few CHD-causing genes have been identified so far. A promising approach for the identification of essential cardiac regulators whose mutations may be linked to human CHD, is the molecular and genetic analysis of heart development. With the use of a triple retinoic acid competitive antagonist (BMS189453) we previously developed a mouse model of congenital heart defects (81%), thymic abnormalities (98%) and neural tube defects (20%). D-TGA (D-transposition of great arteries) was the most prevalent cardiac defect observed (61%). Recently we were able to partially rescue this abnormal phenotype (CHD were reduced to 64.8%, p = 0.05), by oral administration of folic acid (FA). Now we have performed a microarray analysis in our mouse models to discover genes/transcripts potentially implicated in the pathogenesis of this CHD.Results: We analysed mouse embryos (8.5 dpc) treated with BMS189453 alone and with BMS189453 plus folic acid (FA) by microarray and qRT-PCR. By selecting a fold change (FC) >= +/- 1.5, we detected 447 genes that were differentially expressed in BMS-treated embryos vs. untreated control embryos, while 239 genes were differentially expressed in BMS-treated embryos whose mothers had also received FA supplementation vs. BMS-treated embryos. On the basis of microarray and qRT-PCR results, we further analysed the Hif1 alpha gene. In fact Hif1 alpha is down-regulated in BMS-treated embryos vs. untreated controls (FCmicro = -1.79; FCqRT-PCR = -1.76; p = 0.005) and its expression level is increased in BMS+FA-treated embryos compared to BMS-treated embryos (FCmicro = +1.17; FCqRT-PCR = +1.28: p = 0.005). Immunofluorescence experiments confirmed the under-expression of Hif1 alpha protein in BMS-treated embryos compared to untreated and BMS+FA-treated embryos and, moreover, we demonstrated that at 8.5 dpc, Hif1 alpha is mainly expressed in the embryo heart region.Conclusions: We propose that Hif1 alpha down-regulation in response to blocking retinoic acid binding may contribute to the development of cardiac defects in mouse newborns. In line with our hypothesis, when Hif1a expression level is restored (by supplementation of folic acid), a decrement of CHD is found. To the best of our knowledge, this is the first report that links retinoic acid metabolism to Hif1 alpha regulation and the development of D-TGA.