Massive rearrangements of cellular MicroRNA signatures are key drivers of hepatocyte dedifferentiation
Massive rearrangements of cellular MicroRNA signatures are key drivers of hepatocyte dedifferentiation
复制标题
DOI：
10.1002/hep.28780
复制
发表时间：
2016-11-01
期刊：
影响因子：
13.5
通讯作者：
Ingelman-Sundberg, Magnus
中科院分区：
文献类型：
--
作者：
Lauschke, Volker M.;Vorrink, Sabine U.;Ingelman-Sundberg, Magnus
肝细胞是动态的细胞，在受到损伤后，在体内可以在非分裂分化和去分化增殖状态之间交替。然而，在二维培养中，原代人肝细胞（PHHs）迅速去分化，导致肝功能丧失，这大大限制了它们作为肝脏生物学、肝脏疾病以及药物代谢和毒性的体外模型的实用性。因此，了解去分化过程的潜在机制和延迟将非常有助于建立更准确和相关的长期体外肝细胞模型。在这里，我们展示了在培养的前24小时内脱分化开始期间的全蛋白质组和转录组动力学的综合分析。我们报道，在phh去分化过程中，非编码转录组的早期主要重排，以小核仁rna、长链非编码rna、microRNAs （miRNAs）和核糖体基因的表达增加为特征，先于编码基因的大多数变化，我们推测这些调节可能驱动肝脏去分化过程。为了从功能上验证这一假设，我们使用两种化学上不同的化合物——吖啶黄碱和聚赖氨酸，在全球范围内抑制了miRNA机制。这些抑制实验导致miRNA反应显著受损，最重要的是，对肝功能重要的肝脏基因的下调明显减少。因此，我们为非编码rna，特别是mirna在肝脏去分化中的重要性提供了强有力的证据，这可以帮助开发更有效的干细胞源性肝细胞分化方案，并扩大我们对肝细胞在肝脏再生方面的动态特性的理解。结论：mirna是肝脏去分化的重要驱动因素，我们的研究结果为肝脏再生背后的机制和体外抑制去分化的可能性提供了有价值的信息。(肝脏病学64:1743 2016;1756)
Hepatocytes are dynamic cells that, upon injury, can alternate between nondividing differentiated and dedifferentiated proliferating states in vivo. However, in two-dimensional cultures, primary human hepatocytes (PHHs) rapidly dedifferentiate, resulting in loss of hepatic functions that significantly limits their usefulness as an in vitro model of liver biology, liver diseases, as well as drug metabolism and toxicity. Thus, understanding the underlying mechanisms and stalling of the dedifferentiation process would be highly beneficial to establish more-accurate and relevant long-term in vitro hepatocyte models. Here, we present comprehensive analyses of whole proteome and transcriptome dynamics during the initiation of dedifferentiation during the first 24 hours of culture. We report that early major rearrangements of the noncoding transcriptome, hallmarked by increased expression of small nucleolar RNAs, long noncoding RNAs, microRNAs (miRNAs), and ribosomal genes, precede most changes in coding genes during dedifferentiation of PHHs, and we speculated that these modulations could drive the hepatic dedifferentiation process. To functionally test this hypothesis, we globally inhibited the miRNA machinery using two established chemically distinct compounds, acriflavine and poly-l-lysine. These inhibition experiments resulted in a significantly impaired miRNA response and, most important, in a pronounced reduction in the down-regulation of hepatic genes with importance for liver function. Thus, we provide strong evidence for the importance of noncoding RNAs, in particular, miRNAs, in hepatic dedifferentiation, which can aid the development of more-efficient differentiation protocols for stem-cell-derived hepatocytes and broaden our understanding of the dynamic properties of hepatocytes with respect to liver regeneration. Conclusion: miRNAs are important drivers of hepatic dedifferentiation, and our results provide valuable information regarding the mechanisms behind liver regeneration and possibilities to inhibit dedifferentiation in vitro. (Hepatology 2016;64:1743-1756)