Zadora Julianna, Singh Manvendra, Herse Florian, Przybyl Lukasz, Haase Nadine, Golic Michaela, Yung Hong Wa, Huppertz Berthold, Cartwright Judith E, Whitley Guy, Johnsen Guro M, Levi Giovanni, Isbruch Annette, Schulz Herbert, Luft Friedrich C, Müller Dominik N, Staff Anne Cathrine, Hurst Laurence D, Dechend Ralf, Izsvák Zsuzsanna
From Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany (J.Z., M.S., F.H., N.H., D.N.M., Z.I.); Experimental and Clinical Research Center, a joint cooperation between the Max-Delbrück Center for Molecular Medicine in the Helmholtz Association and the Charité-Universitätsmedizin Berlin, Germany (J.Z., F.H., L.P., N.H., M.G., H.S., F.C.L., D.N.M., R.D.); Berlin Institute of Health, Germany (J.Z., F.H., L.P., N.H., M.G., F.C.L., D.N.M., R.D., Z.I.); Department of Obstetrics and Department of Gynecology, Charité-Universitätsmedizin Berlin, Germany (M.G.); German Centre for Cardiovascular Research, partner site Berlin, Germany (N.H., D.N.M.); Centre for Trophoblast Research, University of Cambridge, UK (H.W.Y.); Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Austria (B.H.); Molecular and Clinical Sciences Research Institute, St George's University of London, UK (J.E.C., G.W.); Division of Obstetrics and Gynaecology, Oslo University Hospital, Norway (G.M.J., A.C.S.); University of Oslo, Norway (G.M.J., A.C.S.); Évolution des Régulations Endocriniennes, Muséum Nationale d'Histoire Naturelle, Paris, France (G.L.); HELIOS-Klinikum, Berlin, Germany (A.I., R.D.); Cologne Center for Genomics, University of Cologne, Germany (H.S.); and Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, UK (L.D.H.).
Circulation. 2017 Nov 7;136(19):1824-1839. doi: 10.1161/CIRCULATIONAHA.117.028110. Epub 2017 Sep 13.
Preeclampsia is a complex and common human-specific pregnancy syndrome associated with placental pathology. The human specificity provides both intellectual and methodological challenges, lacking a robust model system. Given the role of imprinted genes in human placentation and the vulnerability of imprinted genes to loss of imprinting changes, there has been extensive speculation, but no robust evidence, that imprinted genes are involved in preeclampsia. Our study aims to investigate whether disturbed imprinting contributes to preeclampsia.
We first aimed to confirm that preeclampsia is a disease of the placenta by generating and analyzing genome-wide molecular data on well-characterized patient material. We performed high-throughput transcriptome analyses of multiple placenta samples from healthy controls and patients with preeclampsia. Next, we identified differentially expressed genes in preeclamptic placentas and intersected them with the list of human imprinted genes. We used bioinformatics/statistical analyses to confirm association between imprinting and preeclampsia and to predict biological processes affected in preeclampsia. Validation included epigenetic and cellular assays. In terms of human specificity, we established an in vitro invasion-differentiation trophoblast model. Our comparative phylogenetic analysis involved single-cell transcriptome data of human, macaque, and mouse preimplantation embryogenesis.
We found disturbed placental imprinting in preeclampsia and revealed potential candidates, including and , with poorly explored imprinted status and no prior association with preeclampsia. As a result of loss of imprinting, was upregulated in 69% of preeclamptic placentas. Levels of correlated with classic preeclampsia markers. DLX5 is expressed in human but not in murine trophoblast. The DLX5 phenotype resulted in reduced proliferation, increased metabolism, and endoplasmic reticulum stress-response activation in trophoblasts in vitro. The transcriptional profile of such cells mimics the transcriptome of preeclamptic placentas. Pan-mammalian comparative analysis identified as part of the human-specific regulatory network of trophoblast differentiation.
Our analysis provides evidence of a true association among disturbed imprinting, gene expression, and preeclampsia. As a result of disturbed imprinting, the upregulated affects trophoblast proliferation. Our in vitro model might fill a vital niche in preeclampsia research. Human-specific regulatory circuitry of might help explain certain aspects of preeclampsia.
子痫前期是一种复杂且常见的人类特有的妊娠综合征，与胎盘病理相关。人类特异性带来了知识和方法上的挑战，因为缺乏强大的模型系统。鉴于印记基因在人类胎盘形成中的作用以及印记基因对印记丢失变化的易感性，人们进行了广泛的推测，但没有确凿证据表明印记基因与子痫前期有关。我们的研究旨在调查印记紊乱是否导致子痫前期。
我们首先旨在通过生成和分析关于特征明确的患者材料的全基因组分子数据来确认子痫前期是一种胎盘疾病。我们对来自健康对照和子痫前期患者的多个胎盘样本进行了高通量转录组分析。接下来，我们在子痫前期胎盘中鉴定出差异表达基因，并将它们与人类印记基因列表进行比对。我们使用生物信息学/统计分析来确认印记与子痫前期之间的关联，并预测子痫前期中受影响的生物学过程。验证包括表观遗传学和细胞分析。就人类特异性而言，我们建立了一种体外侵袭 - 分化滋养层细胞模型。我们的比较系统发育分析涉及人类、猕猴和小鼠植入前胚胎发育的单细胞转录组数据。
我们发现子痫前期存在胎盘印记紊乱，并揭示了潜在的候选基因，包括[具体基因1]和[具体基因2]，其印记状态研究较少且之前与子痫前期无关联。由于印记丢失，[具体基因1]在69%的子痫前期胎盘中上调。[具体基因1]的水平与经典子痫前期标志物相关。DLX5在人类滋养层细胞中表达，但在鼠类滋养层细胞中不表达。DLX5表型导致体外滋养层细胞增殖减少、代谢增加以及内质网应激反应激活。此类细胞的转录谱模拟了子痫前期胎盘的转录组。全哺乳动物比较分析确定[具体基因2]是人类特异性滋养层细胞分化调控网络的一部分。
我们的分析提供了印记紊乱、基因表达与子痫前期之间真实关联的证据。由于印记紊乱，上调的[具体基因1]影响滋养层细胞增殖。我们的体外模型可能填补子痫前期研究中的一个重要空白。[具体基因2]的人类特异性调控回路可能有助于解释子痫前期的某些方面。
