The role of lncRNAs in P450-mediated drug metabolism and drug-induced liver injury

摘要 该项目的目的是确定HNF1A-AS1和HNF1A-AS1的长非编码RNA(LncRNAs)的作用 HNF4a-AS1对细胞色素P450(CYP)基因表达的调节。药物代谢的细胞色素P450 酶对60%-70%的药物的治疗效果起作用。了解以下方面的所有关键因素 细胞色素P450酶的表达调控是预测药物治疗效果的关键。 肝细胞核因子1a、4a、孕烷X受体转录因子 雄激素受体(PXR)和组成型雄烷受体(CAR)是关键因素。在绑定到他们的响应之后 元件，转录因子通过改变组蛋白修饰状态来促进转录调控 在CYP基因中，主要的表观遗传机制。剩下的问题是TFS是如何触发的 组蛋白修饰的改变，以促进CYP表达的调节。InncRNA可能是 关键组件。越来越多的证据表明，染色体上紧邻转铁蛋白的反义lncRNA 转录因子在基因表达调控中的功能与基因的位置有关。我们确认了两个 HNF1a和HNF4a的转录因子旁边的lncRNAs，即HNF1a-AS1和HNF4a-AS1。几个 需要解决根本的挑战问题。(1)HNF1a-AS1和HNF4a-AS1是否 在动态过程中维持肝脏P450酶的动态平衡的两个关键因素，如 药物诱导，通过HNF1A-AS1增强或HNF4a-AS1抑制转录 P450基因表达的调控？(2)HNF1A-AS1和HNF4a-AS1是否是两个关键因素 在药物性肝损伤(DILI)的敏感性和随后的肝再生过程中？ (3)HNF1a-AS1和HNF4a-AS1如何直接或间接参与P450基因表达的调控 通过改变组蛋白修饰间接调节PXR或CAR？这些 对于深入理解调控中的分子机制，基本问题是至关重要的 CYP介导的药物代谢与DILI的关系。在过去的五年里，我们确定了 IncRNA在药物代谢中的作用。我们最近的进展使我们处于适当的地位，可以提供 这些基本问题的答案。我们已经制定了一项全面的计划来解决这些问题 在接下来的五年里，挑战体外和体内模型的问题。在完成后 关于拟议的研究，我们期望为解决这些挑战问题提供答案。建议数 工作将阐明通过lncRNA控制药物的动态平衡的表观遗传调控机制。 暴露于药物后在正负反馈循环中代谢CYP的表达。这个 拟议的工作将确定lncRNAs在P450介导的药物代谢和敏感性中的作用 敬帝力。生成的知识将有助于识别预测疗效的新关键因素 还有帝力。

ABSTRACT The aim of the project is to determine the roles of long non-coding RNAs (lncRNAs) of HNF1a-AS1 and HNF4a-AS1 in the regulation of cytochrome P450 (CYP) gene expression. Drug-metabolizing CYP enzymes are responsible for therapeutic outcomes of 60-70% drugs. Understanding all key factors in the regulation of expression of the CYP enzymes is critical to predict outcomes of drug therapy. Transcription factors (TFs) of hepatocyte nuclear factor 1a (HNF1a), 4a (HNF4a), pregnane X receptor (PXR), and constitutive androstane receptor (CAR) are the key factors. After binding to their response elements, the TFs facilitate transcriptional regulation through alterations of histone modification status of the CYP genes, the major epigenetic mechanism. A remaining question is how the TFs trigger alterations of histone modifications to facilitate the regulation of CYP expression. lncRNAs may be the key components. Increasing evidence has shown that antisense lncRNAs next to TFs on chromosomal locations are involved in the functions of the TFs in regulation of gene expression. We identified two lncRNAs next to the TFs of HNF1a and HNF4a, which are HNF1a-AS1 and HNF4a-AS1. Several fundamental challenge questions need to be addressed. (1) Whether HNF1a-AS1 and HNF4a-AS1 are the two key factors in maintaining homeostasis of P450 enzymes in liver in a dynamic process, such as drug induction, through enhancing by HNF1a-AS1 or repressing by HNF4a-AS1 in the transcriptional regulation of P450 gene expression? (2) Whether HNF1a-AS1 and HNF4a-AS1 are the two key factors in sensitizing susceptibility of drug induced liver injury (DILI) and following process of liver regeneration? (3) How HNF1a-AS1 and HNF4a-AS1 participate in the regulation of P450 gene expression, directly or indirectly through the regulation of PXR or CAR by alteration of histone modifications? These fundamental questions are so critical for deeply understanding molecular mechanisms in the regulation of CYP-mediated drug metabolism and DILI. In the past five years, we have determined the role of lncRNAs in drug metabolism. Our recent progress has placed us into an appropriate position to provide answers to these fundamental questions. We have developed a comprehensive plan to address these challenge questions with both in vitro and in vivo models in the next five years. After completion of the proposed studies, we expect to provide answers to address the challenge questions. The proposed work will elucidate the epigenetic regulatory mechanisms by lncRNAs that control homeostasis of drug- metabolizing CYP expression in a positive and negative feedback loop after exposure to drugs. The proposed work will determine the roles of lncRNAs in P450-mediated drug metabolism and susceptibility to DILI. The generated knowledge will help to identify novel key factors for predicting therapeutic efficacy and DILI.