Abstract：
Preeclampsia is a major contributor to maternal and fetal morbidity and mortality. The disorder can be classified into early- and late-onset subtypes, both of which evolve in two stages. The first stage comprises the development of pre-clinical, utero-placental malperfusion. Early and late utero-placental malperfusion have different causes and time courses. Early-onset preeclampsia (20 % of cases) is driven by dysfunctional placentation in the first half of pregnancy. In late-onset preeclampsia (80 % of cases), malperfusion is a consequence of placental compression within the confines of a limited uterine cavity. In both subtypes, the malperfused placenta releases stress signals into the maternal circulation. These stress signals trigger onset of the clinical syndrome (the second stage). Small RNA molecules, which are implicated in cellular stress responses in general, may be involved at different stages. Micro RNAs contribute to abnormal trophoblast invasion, immune dysregulation, angiogenic imbalance, and syncytiotrophoblast-derived extracellular vesicle signalling in preeclampsia. Transfer RNA fragments are placental signals known to be specifically involved in cell stress responses. Disorder-specific differences in small nucleolar RNAs and piwi-interacting RNAs have also been reported. Here, we summarise key small RNA advances in preeclampsia pathogenesis. We propose that existing small RNA classifications are unhelpful and that non-biased assessment of RNA expression, incorporation of non-annotated molecules and consideration of chemical modifications to RNAs may be important in elucidating preeclampsia pathogenesis.
摘要：
先兆子痫是孕产妇和胎儿发病率和死亡率的主要原因。该疾病可分为早发和迟发亚型，两者都分为两个阶段。第一阶段包括临床前的发展，子宫胎盘灌注不良。早期和晚期子宫胎盘灌注不良有不同的原因和时间过程。早发型先兆子痫（占病例的20％）是由妊娠前半期的功能失调引起的。在晚发型先兆子痫（80%的病例）中，灌注不良是在有限的子宫腔内胎盘受压的结果。在这两个亚型中，胎盘灌注不良将应激信号释放到母体循环中。这些压力信号触发临床综合征(第二阶段)的发作。小RNA分子,通常与细胞应激反应有关，可能涉及不同阶段。微小RNA有助于异常滋养细胞的侵袭，免疫失调，血管生成失衡，和先兆子痫中合胞体滋养层来源的细胞外囊泡信号。转移RNA片段是已知特异性参与细胞应激反应的胎盘信号。还报道了小核仁RNA和piwi相互作用RNA中的疾病特异性差异。这里,我们总结了小RNA在先兆子痫发病机制中的研究进展.我们认为现有的小RNA分类是无益的，并且对RNA表达的非偏倚评估，非注释分子的掺入和对RNA化学修饰的考虑在阐明先兆子痫的发病机制中可能是重要的。
