Early Postimplantation Research Articles

Impella versus IABP in acute myocardial infarction complicated by cardiogenic shock

ObjectiveWe investigated the benefit of Impella, a modern percutaneous mechanical support (pMCS) device, versus former standard intra-aortic balloon pump (IABP) in acute myocardial infarction complicated by cardiogenic shock (AMICS).MethodsThis single-centre,...

Isolation and Culture of Periimplantation and Early Postimplantation Mouse Embryos.

Key developmental processes of cell fate decisions and morphogenetic transformations take place during the periimplantation and early postimplantation stages of mouse embryogenesis. Howeveranalysing these fundamental events relies on direct observations of cultured embryos, which are challenging to obtain. To address this challenge,here we provide a detailed protocol describing a workflow for isolating early implanted embryos, removing of redundant extraembryonic tissues anddescribing the culture conditions that support further embryo development in vitro.

Highly Efficient Derivation of Pluripotent Stem Cells from Mouse Preimplantation and Postimplantation Embryos in Serum-Free Conditions.

Pluripotency refers to the potential of cells to generate all cell types of the embryo proper. Pluripotency spans a spectrum of cellular states. At one polar extreme is naïve pluripotency, which is identified based on the potential to form germline chimeras. At the other polar extreme is primed pluripotency, in which pluripotent cells are primed to differentiate. Mouse naïve PS cells can be derived from preimplantation embryos. Primed epiblast stem (EpiS) cells are typically isolated from epiblasts of early postimplantation mouse embryos. In this chapter, we describe protocols for highly efficient derivation and propagation of murine naïve and primed PS cell lines in serum-free conditions from preimplantation and postimplantation embryos. We describe generation of mouse naïve PS cells using LIF and inhibitors of MEK and GSK3 kinases and of mouse primed PS cells using FGF2 and IWR1 compound which induces the stabilization of Axin proteins.

Isolation of High-Molecular-Weight DNA from Mouse Yolk Sacs and the Like.

Often, genotyping of mouse embryos is required, and a small part, such as the yolk sac, can be used for this purpose. Here, DNA samples are prepared from extra-embryonic tissues by digestion with Proteinase K and subsequent extraction. The yolk sac of mid-gestation or later-stage embryos provides a sufficient amount of DNA for Southern analysis. Small tissues of a few hundred cells are used for genotyping early postimplantation- and preimplantation-stage embryos by polymerase chain reaction (PCR).

Single-Cell Rna-Seq Reveals Cellular Heterogeneity of Pluripotency Transition and X-Chromosome Dynamics During Early Postimplantation Mouse Development

Following implantation, the epiblast (EPI) cells transit from the naive to the primed pluripotency state in preparation for gastrulation, a momentous developmental milestone of the formation of the three primary germ layers. To investigate the molecular attributes of this critical developmental process of lineage specification and the dynamic changes in X-chromosome activity, we performed Smart-seq2 single-cell RNA-seq analysis of 1724 mouse E5.25 to E6.5 embryonic cells. We identified three distinct cellular states in the EPI cells that mirrors the transition of postimplantation EPI along the continuum of naive to primed pluripotency and the acquisition of primitive streak propensity over time. The transition of the EPI cellular state was accompanied by enhanced interaction with the visceral endoderm mediated by inductive signalling activity. By tracing X-chromosome activity at the allelic resolution, we discovered that X-chromosome reactivation (XCR) was initiated prior to the complete silencing of imprinted X-chromosome in the EPI, and followed by asynchronous random X-chromosome inactivation (XCI). Moreover, imprinted X-chromosome inactivation proceeded with a faster kinetics in the visceral endoderm compared to the extraembryonic ectoderm. Our study has outlined in detail a molecular roadmap of the emergent process of lineage specification and X-chromosome reprogramming during mouse pregastrulation development.

Diet-induced obesity alters the maternal metabolome and early placenta transcriptome and decreases placenta vascularity in the mouse.

Maternal obesity is associated with an increased risk of obesity and metabolic disease in offspring. Increasing evidence suggests that the placenta plays an active role in fetal programming. In this study, we used a mouse model of diet-induced obesity to demonstrate that the abnormal metabolic milieu of maternal obesity sets the stage very early in pregnancy by altering the transcriptome of placenta progenitor cells in the preimplantation (trophectoderm [TE]) and early postimplantation (ectoplacental cone [EPC]) placenta precursors, which is associated with later changes in placenta development and function. Sphingolipid metabolism was markedly altered in the plasma of obese dams very early in pregnancy as was expression of genes related to sphingolipid processing in the early placenta. Upregulation of these pathways inhibits angiogenesis and causes endothelial dysfunction. The expression of many other genes related to angiogenesis and vascular development were disrupted in the TE and EPC. Other key changes in the maternal metabolome in obese dams that are likely to influence placenta and fetal development include a marked decrease in myo and chiro-inositol. These early metabolic and gene expression changes may contribute to phenotypic changes in the placenta, as we found that exposure to a high-fat diet decreased placenta microvessel density at both mid and late gestation. This is the first study to demonstrate that maternal obesity alters the transcriptome at the earliest stages of murine placenta development.

Selection against BALB/c strain cells in mouse chimaeras.

ABSTRACTIt has been shown previously that BALB/c strain embryos tend to contribute poorly to mouse aggregation chimaeras. In the present study we showed that BALB/c cells were not preferentially allocated to any extraembryonic lineages of mouse aggregation chimaeras, but their contribution decreased during the early postimplantation period and they were significantly depleted by E8.5. The development of BALB/c strain preimplantation embryos lagged behind embryos from some other strains and the contribution that BALB/c and other embryos made to chimaeras correlated with their developmental stage at E2.5. This relationship suggests that the poor contribution of BALB/c embryos to aggregation chimaeras is at least partly a consequence of generalised selection related to slow or delayed preimplantation development. The suitability of BALB/c embryos for maximising the ES cell contribution to mouse ES cell chimaeras is also discussed.

Functional and phenotypic distinction of the first two trophoblast subdivisions and identification of the border between them during early postimplantation: A prerequisite for understanding early patterning during placentogenesis

The early stages of mouse placentogenesis (placenta formation) involve poorly understood patterning events within polar trophectoderm-derived trophoblast, the progenitor of all placental trophoblast cell types. By early postimplantation [embryonic day 5.5 (E5.5)], this patterning causes early trophoblast to become subdivided into extraembryonic ectoderm (ExE) and ectoplacental cone (EPC). A prerequisite to understanding this patterning requires knowing the location of ExE-EPC border and being able to distinguish the entire ExE from EPC at E5.5/E6.5, a time when the proamnioitic cavity within ExE is not fully established. However, these issues are unknown, as they have not been directly addressed. Here, we directly addressed these using trophoblast explant culture to functionally test for the location of ExE-EPC border, combined with phenotypic characterization of trophoblast proximal and distal to it. We show for the first time that the proximal-distal level of ExE-EPC border within E5.5/E6.5 trophoblast coincides with where Reichert's membrane (outermost basement membrane of conceptus) inserts into early trophoblast and with the proximal limit of extraembryonic visceral endoderm (primitive endoderm derivative covering part of early trophoblast). Based on these novel findings, we discovered that (a) the entire E5.5/E6.5 ExE can be distinguished from EPC because it is epithelial and specifically expresses Erf and Claudin4 and (b) at E5.5/E6.5, the entire EPC differs from ExE in that it is not epithelial and specifically expresses Snail. This work is expected to contribute to understanding the cellular and molecular basis of early trophoblast patterning during placentogenesis.

Parthenogenetic Activation of Oocytes.

Numerous studies have been initiated to investigate the influence of maternal and paternal genomes on early mammalian development. For this type of study, parthenogenetic embryos provide a unique source of preimplantation and early postimplantation embryos that (by definition) develop in the absence of any contribution from a male gamete. Parthenogenetic activation is used for biochemical and morphological studies of oocytes during fertilization and early development and is a critical component of the cloning procedure. This protocol describes the activation of oocytes using ethanol. Parthenogenesis can also be induced by exposure of unfertilized oocytes to strontium-containing medium.

Transcatheter pulmonary valve replacement using the melody valve for treatment of dysfunctional surgical bioprostheses: A multicenter study

BackgroundStented bioprosthetic valves (BPVs) are commonly used for surgical pulmonary valve (PV) replacement in postoperative congenital heart disease, but develop structural failure in a time-related fashion. The Melody transcatheter PV (TPV) (Medtronic, Minneapolis, Minn) has been used to treat BPV dysfunction, but there have been few studies in this population. MethodsWe performed a retrospective, multicenter study to evaluate Melody valve function in patients who underwent TPV replacement (TPVR) into a dysfunctional pulmonary BPV. ResultsOne hundred patients who underwent TPVR at 10 centers between January 2010 and June 2015 were enrolled. The median patient age was 22 years (range, 5-79 years), and 32 patients were age <18 years. The underlying diagnosis was tetralogy of Fallot in 80 patients, and moderate or severe pulmonary regurgitation (PR) was present in 84%. The TPV was implanted into various types of BPVs, with a median size of 23 mm (range, 19-33 mm). At hospital discharge, PR was mild or less in all but 1 patient, and the mean Doppler right ventricular outflow tract (RVOT) gradient was reduced from a mean of 29.3 ± 12.0 mm Hg to 16.2 ± 6.9 mm Hg (median, 29 mm Hg to 16 mm Hg; P < .001). During follow-up (median, 12.4 months), no patients underwent reintervention on the TPV. Endocarditis was diagnosed in 1 patient who was managed medically without intervention. The mean RVOT gradient at the most recent follow-up was ≤35 mm Hg in all patients, and was similar to that at early postimplantation. PR was more than mild in only 1 patient. Hemodynamic outcomes did not differ between patients with small BPVs (≤23 mm) and those with large BPVs (≥25 mm). ConclusionsTPVR restores competence and relieves the obstruction of dysfunctional surgical BPVs, with excellent early results in both small and large BPVs, highlighting the potential for TPVR to extend the life of existing BPVs in adults and children. Collaboration between surgeons and cardiologists is important to determine the optimal lifetime management, combining surgical PV replacement and TPVR in this population.

Berberine impairs embryonic development in vitro and in vivo through oxidative stress-mediated apoptotic processes.

Berberine, an isoquinoline alkaloid isolated from several traditional Chinese herbal medicines, has been shown to suppress growth and induce apoptosis in some tumor cell lines. However, berberine has also been reported to attenuate H2 O2 -induced oxidative injury and apoptosis. The basis for these ambiguous effects of berberine-triggering or preventing apoptosis-has not been well characterized to date. In the current investigation, we examined whether berberine exerts cytotoxic effects on mouse embryos at the blastocyst stage and affects subsequent embryonic development in vitro and in vivo. Treatment of blastocysts with berberine (2.5-10 μM) induced a significant increase in apoptosis and a corresponding decrease in trophectoderm cell number. Moreover, the implantation success rate of blastocysts pretreated with berberine was lower than that of their control counterparts. Pretreatment with berberine was also associated with increased resorption of postimplantation embryos and decreased fetal weight. In an animal model, intravenous injection of berberine (2, 4, or 6 mg/kg body weight/d) for 4 days resulted in apoptosis of blastocyst cells and early embryonic developmental injury. Berberine-induced injury of mouse blastocysts appeared to be attributable to oxidative stress-triggered intrinsic apoptotic signaling processes that impaired preimplantation and postimplantation embryonic development. Taken together, our results clearly demonstrate that berberine induces apoptosis and retards early preimplantation and postimplantation development of mouse embryos, both in vitro and in vivo.

Early Gestational Hypoxia and Adverse Developmental Outcomes.

Hypoxia is a normal and essential part of embryonic development. However, this state may leave the embryo vulnerable to damage when oxygen supply is disturbed. Embryofetal response to hypoxia is dependent on duration and depth of hypoxia, as well as developmental stage. Early postimplantation rat embryos were resilient to hypoxia, with many surviving up to 1.5 hr of uterine clamping, while most mid-gestation embryos were dead after 1 hour of clamping. Survivors were small and many had a range of defects, principally terminal transverse limb reduction defects. Similar patterns of malformations occurred when embryonic hypoxia was induced by maternal hypoxia, interruption of uteroplacental flow, or perfusion and embryonic bradycardia. There is good evidence that high altitude pregnancies are associated with smaller babies and increased risk of some malformations, but these results are complicated by increased risk of pre-eclampsia. Early onset pre-eclampsia itself is associated with small for dates and increased risk of atrio-ventricular septal defects. Limb defects have clearly been associated with chorionic villus sampling, cocaine, and misoprostol use. Similar defects are also observed with increased frequency among fetuses who are homozygous for thalassemia. Drugs that block the potassium current, whether as the prime site of action or as a side effect, are highly teratogenic in experimental animals. They induce embryonic bradycardia, hypoxia, hemorrhage, and blisters, leading to transverse limb defects as well as craniofacial and cardiovascular defects. While evidence linking these drugs to birth defects in humans is not compelling, the reason may methodological rather than biological. Birth Defects Research 109:1358-1376, 2017.© 2017 Wiley Periodicals, Inc.

Early Postimplant Speech Perception and Language Skills Predict Long-Term Language and Neurocognitive Outcomes Following Pediatric Cochlear Implantation.

We sought to determine whether speech perception and language skills measured early after cochlear implantation in children who are deaf, and early postimplant growth in speech perception and language skills, predict long-term speech perception, language, and neurocognitive outcomes. Thirty-six long-term users of cochlear implants, implanted at an average age of 3.4 years, completed measures of speech perception, language, and executive functioning an average of 14.4 years postimplantation. Speech perception and language skills measured in the 1st and 2nd years postimplantation and open-set word recognition measured in the 3rd and 4th years postimplantation were obtained from a research database in order to assess predictive relations with long-term outcomes. Speech perception and language skills at 6 and 18 months postimplantation were correlated with long-term outcomes for language, verbal working memory, and parent-reported executive functioning. Open-set word recognition was correlated with early speech perception and language skills and long-term speech perception and language outcomes. Hierarchical regressions showed that early speech perception and language skills at 6 months postimplantation and growth in these skills from 6 to 18 months both accounted for substantial variance in long-term outcomes for language and verbal working memory that was not explained by conventional demographic and hearing factors. Speech perception and language skills measured very early postimplantation, and early postimplant growth in speech perception and language, may be clinically relevant markers of long-term language and neurocognitive outcomes in users of cochlear implants. https://doi.org/10.23641/asha.5216200.

Lineage-specific functions of TET1 in the postimplantation mouse embryo.

The mammalian TET enzymes catalyze DNA demethylation. While they have been intensely studied as major epigenetic regulators, little is known about their physiological roles and the extent of functional redundancy following embryo implantation. Here we define non-redundant roles for TET1 at an early postimplantation stage of the mouse embryo, when its paralogs Tet2 and Tet3 are not detectably expressed. TET1 regulates numerous genes defining differentiation programs in the epiblast and extraembryonic ectoderm. In epiblast cells, TET1 demethylates gene promoters via hydroxymethylation and maintains telomere stability. Surprisingly, TET1 represses a majority of epiblast target genes independently of methylation changes, in part through regulation of the gene encoding the transcriptional repressor JMJD8. Dysregulated gene expression in the absence of TET1 causes embryonic defects, which are partially penetrant in an inbred strain but fully lethal in non-inbred mice. Collectively, our study highlights an interplay between the catalytic and non-catalytic activities of TET1 that is essential for normal development.

Impairment of preimplantation and postimplantation embryonic development through intrinsic apoptotic processes by ginsenoside Rg1 in vitro and in vivo.

Ginsenoside Rg1, which is the most abundant compound found in Asian ginseng (Panax ginseng), has demonstrated various pharmacological actions, including neuroprotective, immune-stimulatory, and antidiabetic effects. Pregnant women, especially in the Asian community, consume ginseng as a nutritive supplement. Thus, the effects of ginsenoside-Rg1 on embryonic development need to be investigated, such as in a mouse model. As previous investigations have found that ginsenoside Rg1 appears to either trigger or prevent apoptosis in different cell lines, the effects of this agent on apoptosis remain to be clarified. In this study, we investigated whether ginsenoside Rg1 exerts a hazardous effect on mouse blastocysts and/or affects subsequent embryonic development in vitro and in vivo. Blastocysts treated with 25-100 μM ginsenoside Rg1 exhibited significant induction of apoptosis and a corresponding decrease in the inner cell mass (ICM) cell number. Importantly, the implantation rate was lower among ginsenoside Rg1-treated blastocysts compared to untreated controls. Moreover, embryo transfer assays revealed that blastocysts treated with 100 μM ginsenoside Rg1 exhibited increased resorption of postimplantation embryos and decreased weight among surviving fetuses. In vivo, intravenous injection of mice with ginsenoside Rg1 (2, 4, or 6 mg/kg body weight/day) for 4 days was associated with increased apoptosis of blastocyst-stage embryos and negatively impacted early embryonic development. Further experiments revealed that these effects may reflect the ability of ginsenoside Rg1 to trigger oxidative stress-mediated intrinsic apoptotic signaling. Our in vitro results indicate that ginsenoside Rg1 treatment increases intracellular oxidative stress, decreases mitochondrial membrane potential, increases the Bax/Bcl-2 ratio, and activates caspase-9 and caspase-3, but not caspase-8. Taken together, our study results strongly suggest that ginsenoside Rg1 induces apoptosis and impairs the early preimplantation and postimplantation development of mouse embryos, both in vitro and in vivo.

Xenogeneic Bio-Root Prompts the Constructive Process Characterized by Macrophage Phenotype Polarization in Rodents and Nonhuman Primates.

Tissue or organ regeneration using xenogeneic matrices is a promising approach to address the shortage of donor matrices for allotransplantation. Success of such approach has been demonstrated to correlate with macrophage-mediated fibrotic homeostasis and tissue remodeling. The previous studies have demonstrated that treated dentin matrix (TDM) could be a suitable bioactive substrate for allogeneic tooth root regeneration. This study constructed xenogeneic bioengineered tooth root (bio-root) via a combination of porcine TDM (pTDM) with allogeneic dental follicle cells (DFCs). Macrophage phenotypes are used to evaluate the remodeling process of xenogeneic bio-roots in vitro and in vivo. pTDM can facilitate odontoblast differentiation of human derived DFCs. Xenogeneic bio-roots in rat subcutaneous tissue prompt constructive response via M1 macrophage infiltration during early postimplantation stages and increase restorative M2 phenotype at later stages. After implantation of bio-roots into jaws of rhesus monkeys for six months, periodontal ligament-like fibers accompanied by macrophage polarization are observed, which are positive for COL-1, Periostin, βIII-tubulin and display such structures as fibroblasts and blood vessels. The reconstructed bio-root possesses biomechanical properties for the dissipation of masticatory forces. These results support that xenogeneic bio-root could maintain fibrotic homeostasis during remodeling process and highlight the potential application of xenogeneic matrices in regenerative medicine.

Derivation and Culture of Extra-Embryonic Endoderm Stem Cell Lines.

Whereas embryonic stem (ES) cells are isolated from the embryonic lineage of the blastocyst, other stable stem cell lines can be derived from the extraembryonic tissues of the early mouse embryo. Trophoblast stem (TS) cells are derived from trophectoderm and early postimplantation trophoblast, and extraembryonic endoderm stem (XEN) cells are derived from primitive endoderm. The derivation of XEN cell lines from 3.5-dpc mouse blastocysts, described here, is similar to the derivation of TS cell lines. TS and XEN cells can self-renew in vitro and differentiate in vitro and in chimeras (in vivo) in a lineage-appropriate manner, showing the developmental potential of their origin, thus providing important models to study the mouse extraembryonic lineages.

Derivation and Culture of Epiblast Stem Cell (EpiSC) Lines.

This protocol describes the derivation and culture of epiblast stem cells (EpiSCs) from early postimplantation epiblasts. EpiSCs can be maintained in an undifferentiated state and retain the ability to generate tissues from all three germ layers in vitro and to form teratomas in vivo. However, they seem unable to form chimeras. Whether this is due to differences in developmental status or a cellular incompatibility (e.g., cell adhesion) between EpiSCs and the host inner cell mass (ICM) is currently unclear. Other differences between mouse embryonic stem (ES) cells and EpiSCs also exist, including gene expression profiles and different growth factor requirements for self-renewal. Thus, EpiSCs provide an important in vitro model for studying the establishment and maintenance of pluripotency in postimplantation epiblast tissues.

The Influence of Mesodiencephalic Modulation on the Course of Postoperative Period and Osseointegration Quality in case of Intraosseus Dental Implantation

Objectives: A favorable character of the early postimplantation period progression largely determines the success of the ongoing orthopedic treatment. The aim of our study was to assess the effectiveness of MDM-therapy after dental implantation to prevent inflammatory complications, improve osseointegration quality and increase the installed implant stability. Method: Despite the presence of articulated ideas about the surveillance of patients undergoing dental implantation, incidence of infectious complications, occurring after the operation, as well as the absence of full-fledged osseointegration in some cases, forced practitioners to resort to additional measures that increase the clinical results of the treatment. Our attention was drawn by mesodiencephalic modulation method and its possibilities regarding the optimization of the recovery period and stimulation of internal resources of the patient. Scientific-experimental and clinical laboratory methods are the key ones of the present study. Findings: We have compared early and late clinical and laboratory findings of dental implantation in two patient populations (with MDM-therapy and without applying additional therapy in the postoperative period); some patients have experienced an increased gag reflex, which excluded the possibility of using a removable prosthesis. The obtained data were analyzed by mathematical processing with the determined minimum, maximum and average values of the defined indicators and comparison of the results in the two samples. An idea about the factors influencing the postoperative course of dental implantation and the quality of early and late osseointegration was formed. A dynamic assessment of clinical and laboratory parameters characterizing the inflammatory response after implantation in patients who received standard postoperative therapy and the standard treatment combined with the MDM-therapy was carried out. We have measured the performance of early and late stability of the installed dental implants in patients who received various models of accompanying therapy. Application/Improvements: Conclusions have been formulated about the MDM-therapy appropriateness in early postimplantation period for preventing inflammatory complications and increasing stability of the installed dental implants.

Downregulation of miR-199a-5p Disrupts the Developmental Potential of In Vitro-Fertilized Mouse Blastocysts

Although in vitro fertilization (IVF), one of the most effective and successful assisted reproductive technologies, is widely used for treating infertility and in animal breeding, increasing evidence indicates that IVF offspring are linked to various short- or long-term consequences. Erroneous epigenetic modifications induced by IVF are suspected of contributing to these consequences. Among these epigenetic modifications, microRNAs may affect embryo implantation and early postimplantation development. Here, we performed comparative microRNA profiling between in vivo-fertilized (IVO group) and in vitro-fertilized (IVF group) mouse embryos at Embryonic Day 3.5 (E3.5) and E7.5. Our dynamic analyses showed that the dysregulated microRNAs were mainly associated with the regulation of genes involved in carcinogenesis, genetic information processing, glucose metabolism, cytoskeleton organization, and neurogenesis. Further analysis showed that miR-199a-5p was consistently downregulated in IVF embryos compared with their IVO counterparts. Through gain- and loss-of-function experiments, we demonstrated that IVF-induced downregulation of miR-199a-5p results in a higher glycolytic rate and lower developmental potential of IVF blastocysts, including cell lineage misallocation and lower fetal survival post implantation. Therefore, preventing downregulation of miR-199a-5p may become an effective strategy for improving the development of IVF peri-implantation embryos in the future.