The etiology and pathogenesis of pre-eclampsia (PE) is unclear, and there is no ideal early clinical biomarker for prediction of PE. The competing endogenous RNA (ceRNA) hypothesis is a new approach to uncover the molecular pathology of PE. The first aim of this study was to perform messenger RNA, long non-coding RNA, and circular RNA (circRNA) expression profiling of human normal and severe pre-eclampsia (SPE) placentas. circRNA, which has a stable structure, is a more suitable biomarker than other types of RNA. Therefore, the second aim of our study was to select some differentially expressed circRNAs in PE placentas as early clinical biomarkers of PE in blood circulation. Using microarray analysis, we investigated differentially expressed ceRNAs in human normal and SPE placentas. Bioinformatics, such as gene ontology, KEGG pathway, and ceRNA network analyses, were performed to evaluate the microarray data and gain further insights into the biological processes. RNAs (Chd5, Furin, lnc-ELAVL4-9:1, lnc-RAP1GAP2-5:2, hsa_circ_0036877, hsa_circ_0036878, hsa_circ_0055724, hsa_circ_0049730, and hsa_circ_0036474) were validated by quantitative real-time PCR (qRT-PCR). RNA immunoprecipitation (RIP) of AGO2 in htra-8 cells and qRT-PCR analysis of hsa_circ_0036877 expression in maternal whole peripheral blood samples of participants were then conducted to confirm that hsa_circ_0036877 is a ceRNA and potential novel blood biomarker for early PE, respectively. Our study is the first systematic profiling of ceRNAs in placentas of PE patients and revealed the global ceRNA network integration in PE. Moreover, hsa_circ_0036877 can function as a ceRNA and serve as a potential novel blood biomarker for early PE.
Background: Autophagy is required for oogenesis and plays a critical role in response to aging caused by oxidative stress. However, there have been no reports on regulation of cytoprotective autophagy in female germline stem cells (FGSCs) in response to aging caused by oxidative stress.Results: We found that Spermidine (SPD) significantly increased protein expression of autophagy markers microtubule-associated protein 1 light chain 3 beta-II (MAP1LC3B-II/LC3B-II) and sequestosome-1/p62 (SQSTM1/p62), and evoked autophagic flux in FGSCs. Moreover, SPD increased the number and viability of FGSCs in vitro. Further, we found that SPD significantly reduced basal or hydrogen peroxide (H2O2)-induced up-regulated protein expression of the aging markers, cyclin dependent kinase inhibitor 2A (p16/CDKN2A) and tumor protein 53 (p53). After knockdown of p62 in FGSCs, p16 protein levels were significant higher compared with controls. However, protein p16 levels were not significantly changed in p62 knockdown FGSCs with SPD treatment compared with without SPD. Moreover, SPD significantly changed the expression of autophagy-related genes and pathways in FGSCs, as shown by bioinformatics analysis of RNA sequencing data. Additionally, SPD significantly inhibited AKT/mTOR phosphorylation.Conclusions: SPD induces cytoprotective autophagy in FGSCs in vitro and ameliorates cellular senescence of FGSCs induced by H2O2. Furthermore, SPD can ameliorate cellular senescence of FGSCs through p62. SPD might induce autophagy in FGSCs via the PI3K/Akt pathway. Our findings could be helpful for delaying aging of female germ cells due to oxidative stress and preserving female fertility.
Postnatal female germline stem cells (FGSCs) are a type of germline stem cell with self-renewal ability and the capacity of differentiation toward oocyte. The proliferation, differentiation, and apoptosis of FGSCs have been researched in recent years, but autophagy in FGSCs has not been explored. This study investigated the effects of the small-molecule compound 89 (C89) on FGSCs and the underlying molecular mechanism in vitro. Cytometry, Cell Counting Kit-8 (CCK8), and 5-ethynyl-2’-deoxyuridine (EdU) assay showed that the number, viability, and proliferation of FGSCs were significantly reduced in C89-treated groups (0.5, 1, and 2 µM) compared with controls. C89 had no impact on FGSC apoptosis or differentiation. However, C89 treatment induced the expression of light chain 3 beta II (LC3BII) and reduced the expression of sequestosome-1 (SQSTM1) in FGSCs, indicating that C89 induced FGSC autophagy. To investigate the mechanism of C89-induced FGSC autophagy, RNA-seq technology was used to compare the transcriptome differences between C89-treated FGSCs and controls. Bioinformatics analysis of the sequencing data indicated a potential involvement of the phosphatidylinositol 3 kinase and kinase Akt (PI3K-Akt) pathway in the effects of C89′s induction of autophagy in FGSCs. Western blot confirmed that levels of p-PI3K and p-Akt were significantly reduced in the C89- or LY294002 (PI3K inhibitor)-treated groups compared with controls. Moreover, we found cooperative functions of C89 and LY294002 in inducing FGSC autophagy through suppressing the PI3K-Akt pathway. Taken together, this research demonstrates that C89 can reduce the number, viability, and proliferation of FGSCs by inducing autophagy. Furthermore, C89 induced FGSC autophagy by inhibiting the activity of PI3K and Akt. The PI3K-Akt pathway may be a target to regulate FGSC proliferation and death.
This data descriptor is an extended version of the methodologies which have been described in a related paper [1]; its purpose is to disseminate the raw data and analyzed data produced in this experiment. For more insight please see the research article, "competing endogenous RNA expression profiling in pre-eclampsia identifies hsa_circ_0036877 as a potential novel blood biomarker for early pre-eclampsia" (Xiaopeng Hu and Junping Ao, 2018) [1]. Using microarray analysis, we investigated competing endogenous RNA (ceRNA) expression profiles in placentas of women with severe pre-eclampsia (SPE) and normal pregnancies. Competing endogenous RNA (ceRNA) refer to RNA transcripts, such as messenger RNA (mRNA), long noncoding RNA (lncRNA), and circular RNA (circRNA) that can regulate each other by competing for the same pool of miRNAs. CircRNAs, lncRNAs, and mRNAs differentially expressed between human normal and SPE placentas were obtained in the study. Metadata files were submitted to the Gene Expression Omnibus repository (GEO), with GEO accession number GSE102897. These data are potential useful for further study on the pathogenesis of PE and early prediction of PE onset.
Objectives: This study aimed to clarify the regulation and mechanism of meiotic initiation in FGSC development.Materials and Methods: FGSCs were induced to differentiate into meiosis in differentiation medium. RNA sequencing was performed to analysis the difference of transcription level. High‐through chromosome conformation capture sequencing (Hi‐C) was performed to analysis changes of three‐dimensional chromatin structure. Chromosome conformation capture further confirmed a spatial chromatin loop. ChIP‐qPCR and dual luciferase reporter were used to test the interaction between Stimulated by retinoic acid gene 8 (STRA8) protein and Trip13 promoter.Results: Compared with FGSCs, the average diameter of STRA8‐positive germ cells increased from 13 μm to 16.8 μm. Furthermore, there were 4788 differentially expressed genes between the two cell stages; Meiosis and chromatin structure‐associated terms were significantly enriched. Additionally, Hi‐C results showed that FGSCs underwent A/B compartment switching (switch rate was 29.81%), the number of topologically associating domains (TADs) increasing, the average size of TADs decreasing, and chromatin loop changes at genome region of Trip13 from undifferentiated stage to meiosis‐initiation stage. Furthermore, we validated that Trip13 promoter contacted distal enhancer to form spatial chromatin loop and STRA8 could bind Trip13 promoter to promote gene expression.Conclusion: FGSCs underwent chromatin structure remodelling from undifferentiated stage to meiosis‐initiation stage, which facilitated STRA8 binding to Trip13 promoter and promoting its expression.