Biology subjects

Soncin, F.

Publications and source records attributed to Soncin, F..

4 recordsLinked to original sources

bioRxiv2026

Creatine kinase regulates energy metabolism and growth of trophoblasts

Study questionDoes the human placenta utilize the creatine phosphagen system for energy homeostasis during development? Summary answerComponents of the creatine (Cr)-creatine kinase (CK)-phosphocreatine (PCr) system are dynamically expressed by the trophoblast and mesenchymal compartments throughout gestation wherein creatine kinase is required for cellular ATP metabolism, cell cycle, and proliferation of trophoblast cells. What is known alreadyThe Cr-CK-PCr system maintains ATP homeostasis in tissues with high energy demand and is required for proliferation, migration, and invasion of tumor cells. The term human placenta can synthesize and transport creatine locally. Early placental development involves trophoblast proliferation, an event requiring ATP, but the role of the creatine phosphagen system during early placental development remains unknown. Study design, size, durationWe performed immunohistochemistry (IHC) and immunofluorescence (IF) for different components (biosynthesis, transport, utilization) of the Cr-Ck-PCr system in human placentae (n=3/group) across gestation including first trimester, second trimester, and term. Using primary human trophoblast stem cells (hTSCs) and trophoblast organoids (TO), we determined the role of the creatine phosphagen system in trophoblast growth by functional inhibition of creatine kinase. Participants/materials, setting, methodsIHC/IF were performed in human placentae across gestation for proteins involved in biosynthesis (AGAT and GAMT), transport (SLC6A8, SLC22A15, and SLC6A13) and utilization (CKB and CKMT1) of creatine to determine the presence of the creatine phosphagen system locally in the placenta. For delineating the functional importance of this system in placental development, cyclocreatine (cCr), a creatine analogue, was used for functional inhibition of CK. Primary hTSCs were culture in medium containing 0 (control), 1, 10, 20 mM cCr for 48 hours followed by analysis of cell growth (cell count), cell cycle (EdU incorporation assay), apoptosis (Annexin V/PI flow cytometry), energy metabolism (Sea horse mito-stress and glycolytic stress tests), and gene expression (qPCR). Primary TO were also treated with 20mM cCr for 6 days in vitro to determine the role of Cr-CK-PCr system in placental development. Main results and the role of chanceAGAT localized to the fetal villous mesenchyme, while GAMT was broadly expressed in the trophoblast and fetal mesenchyme compartments across gestation. CKB localized primarily to fetal mesenchyme with strongest expression at term. CKMT1 was broadly expressed in all trophoblast subtypes. SLC6A8 was abundant in early syncytiotrophoblast but absent at term, where its expression shifted to fetal blood vessels. SLC22A15 was expressed in the endothelial cells of fetal capillaries across gestation. In primary hTSCs, cyclocreatine (20mM) treatment reduced proliferation (P<0.001), decreased expression of trophoblast epithelial marker EGFR (P<0.05), induced G0/G1 and G2/M arrests (P<0.0001), enhanced early and late apoptosis (P<0.0001), and downregulated GPX8 expression (P<0.05). Seahorse analysis revealed marked reductions (P<0.01) in mitochondrial (basal, maximal, and ATP-linked) and glycolytic (rate, capacity, and reserve) function compared to controls. In primary human TO, cyclocreatine treatment reduced the growth of organoids (P<0.05) as well the expression of EGFR (P<0.05). Large scale dataN/A Limitations, reasons for cautionFurther experiments assessing apoptosis, cellular stress and redox imbalance may provide more mechanistic role of the creatine phosphagen system in trophoblast metabolism and function. Since the functional role of the Cr-CK-PCr system was investigated in vitro, findings of this study should be taken with caution for implications of in vivo placental development. Nevertheless, reproducible results of reduced growth of trophoblast cells using both 2D and 3D cultures is highly suggestive of the importance of the creatine phosphagen system in early placental development. Wider implications of the findingsThis study provides foundational knowledge that the placenta contains the creatine phosphagen system, known for ATP homeostasis, and that this system ensures proper cell division, survival and placental development. Dysregulation of components of Cr-CK-PCr system in placenta has been observed in pregnancy disorders such as preeclampsia and fetal growth restriction warranting continued investigation into mechanisms and potential remediation using creatine supplementation. Stem cells share similar metabolic features so findings of this study can be implicated in other stem cells models as well. Study funding/competing interest(s)This work was supported by CIRM EDUC4-12804 Interdisciplinary Stem Cell Training Grant and a Lalor Foundation Postdoctoral Fellowship awarded to NS, and by the California Institute for Regenerative Medicine (DISC0-13757) and the National Institute of Child Health and Human Development (R01-HD096260) award to FS. The authors have no competing interest to declare.

physiology↗

bioRxiv2025

VGLL1 contributes to both the transcriptome and epigenome of the developing trophoblast compartment

The trophectoderm (TE), the first lineage specified during mammalian development, initiates implantation and gives rise to placental trophoblasts. While animal models have elucidated key conserved signaling pathways involved in early TE specification, including BMP, WNT, and HIPPO, species-specific differences during early development emphasize the need for human-specific models. We previously identified VGLL1, a coactivator of TEAD transcription factors, as a human-specific placental marker. In this study, we employed a pluripotent stem cell (PSC)-based model of TE induction by BMP4 to investigate chromatin remodeling and transcriptional dynamics during TE formation. BMP4-induced chromatin accessibility changes promoted a trophoblast gene expression program, while mesoderm lineage markers were only transiently expressed upon canonical WNT activation. We found that VGLL1 was expressed downstream of key TE transcription factors (GATA2/3, TFAP2A/C) but was essential for establishment of full trophoblast identity by up-regulating EGFR and reinforcing GATA3 expression through positive feedback. Notably, VGLL1 enhanced canonical WNT signaling via direct regulation of WNT receptors and effectors. We also identified KDM6B, a histone demethylase that removes H3K27me3 repressive marks, as a direct VGLL1 target. KDM6B facilitated activation of bivalent promoters associated with TE markers, linking epigenetic regulation to lineage identity. Our findings establish a mechanistic framework positioning VGLL1 as a central regulator that integrates HIPPO, BMP, and WNT signaling pathways to drive establishment of human TE. Statement of SignificanceEarly development of the human placenta is essential for pregnancy success, yet the mechanisms that guide placental lineage specification remain poorly defined. Using human stem cells, we show how signaling pathways and chromatin remodeling programs work together to direct formation of the trophectoderm, the earliest placental cell type. We identify VGLL1 as a key regulator linking multiple signaling networks to gene expression and epigenetic control. Our findings reveal a species-specific mechanism of placental initiation with broad implications for understanding reproductive disorders, pregnancy loss, and advancing stem cell-based models to study and potentially treat human placental disease.

developmental biology↗

bioRxiv2024

Single-cell transcriptomics reveal differences between chorionic and basal plate cytotrophoblasts and trophoblast stem cells

Cytotrophoblast (CTB) of the early gestation human placenta are bipotent progenitor epithelial cells, which can differentiate into invasive extravillous trophoblast (EVT) and multinucleated syncytiotrophoblast (STB). Trophoblast stem cells (TSC), derived from early first trimester placentae, have also been shown to be bipotential. In this study, we set out to probe the transcriptional diversity of first trimester CTB and compare TSC to various subgroups of CTB. We performed single-cell RNA sequencing on six normal placentae, four from early (6-8 weeks) and two from late (12-14 weeks) first trimester, of which two of the early first trimester cases were separated into basal (maternal) and chorionic (fetal) fractions prior to sequencing. We also sequenced three TSC lines, derived from 6-8 week placentae, to evaluate similarities and differences between primary CTB and TSC. CTB clusters displayed notable distinctions based on gestational age, with early first trimester placentae showing enrichment for specific CTB subtypes, further influenced by origin from the basal or chorionic plate. Differential expression analysis of CTB from basal versus chorionic plate highlighted pathways associated with proliferation, unfolded protein response, and oxidative phosphorylation. We identified trophoblast states representing initial progenitor CTB, precursor STB, precursor and mature EVT, and multiple CTB subtypes. CTB progenitors were enriched in early first trimester placentae, with basal plate cells biased toward EVT, and chorionic plate cells toward STB, precursors. Clustering and trajectory inference analysis indicated that TSC were most like EVT precursor cells, with only a small percentage of TSC on the pre-STB differentiation trajectory. This was confirmed by flow cytometric analysis of 6 different TSC lines, which showed uniform expression of proximal column markers ITGA2 and ITGA5. Additionally, we found that ITGA5+ CTB could be plated in 2D, forming only EVT upon spontaneous differentiation, but failed to form self-renewing organoids; conversely, ITGA5-CTB could not be plated in 2D, but readily formed organoids. Our findings suggest that distinct CTB states exist in different regions of the placenta as early as six weeks gestation and that current TSC lines most closely resemble ITGA5+ CTB, biased toward the EVT lineage.

developmental biology↗

bioRxiv2019

Human iPSC gene signatures and X chromosome dosage impact response to WNT inhibition and cardiac differentiation fate

Non-genetic variability in human induced pluripotent stem cell (iPSC) lines impacts their differentiation outcome, limiting their utility for genetic studies and clinical applications. Despite the importance of understanding how non-genetic molecular variability influences iPSC differentiation outcome, large-scale studies capable of addressing this question have not yet been conducted. Here, we performed 258 directed differentiations of 191 iPSC lines using established protocols to generate iPSC-derived cardiovascular progenitor cells (iPSC-CVPCs). We observed cellular heterogeneity across the iPSC-CVPC samples due to varying fractions of two cell types: cardiomyocytes (CMs) and epicardium-derived cells (EPDCs). Analyzing the transcriptomes of CM-fated and EPDC-fated iPSCs discovered that 91 signature genes and X chromosome dosage differences influence WNT inhibition response during differentiation and are associated with cardiac fate. Analysis of an independent set of 39 iPSCs differentiated to the cardiac lineage confirmed shared sex and transcriptional differences that impact cardiac fate outcome. The scale and systematic approach of our study enabled novel insights into how iPSC transcriptional and X chromosome gene dosage differences influence WNT signaling during differentiation and hence cardiac cell fate.

genomics↗