Expression Of Pluripotency Genes Research Articles

MCT1-mediated transport of valeric acid promotes porcine preimplantation embryo development by improving mitochondrial function and inhibiting the autophagic AMPK-ULK1 pathway

Oocytes and embryos are highly sensitive to environmental stress in vivo and in vitro. During in vitro culture, many stressful conditions can affect embryo quality and viability, leading to adverse clinical outcomes such as abortion and congenital abnormalities. In this study, we found that valeric acid (VA) increased the mitochondrial membrane potential and ATP content, decreased the level of reactive oxygen species that the mitochondria generate, and thus improved mitochondrial function during early embryonic development in pigs. VA decreased expression of the autophagy-related factors LC3B and BECLIN1. Interestingly, VA inhibited expression of autophagy-associated phosphorylation-adenosine monophosphate-activated protein kinase (p-AMPK), phosphorylation-UNC-51-like autophagy-activated kinase 1 (p-ULK1, Ser555), and ATG13, which reduced apoptosis. Short-chain fatty acids (SCFAs) can signal through G-protein-coupled receptors on the cell membrane or enter the cell directly through transporters. We further show that the monocarboxylate transporter 1 (MCT1) was necessary for the effects of VA on embryo quality, which provides a new molecular perspective of the pathway by which SCFAs affect embryos. Importantly, VA significantly inhibited the AMPK-ULK1 autophagic signaling pathway through MCT1, decreased apoptosis, increased expression of embryonic pluripotency genes, and improved embryo quality.

Myocardial Expression of Pluripotency, Longevity, and Proinflammatory Genes in the Context of Hypercholesterolemia and Statin Treatment.

Background: This study sought to assess the effect of statin therapy on myocardial inflammation in a White New Zealand rabbit model of atherogenesis. Methods: The mRNA expression levels of pro-inflammatory, pluripotency, and aging-related markers were quantified following a controlled feeding protocol and statin treatments. Results: Following high-cholesterol diet induction, we observed significant upregulation in the myocardial mRNA levels of MYD88, NF-κB, chemokines (CCL4, CCL20, and CCR2), IFN-γ, interleukins (IL-1β, IL-2, IL-4, IL-8, IL-10, and IL-18), and novel markers (klotho, KFL4, NANOG, and HIF1α). In contrast, HOXA5 expression was diminished following a hyperlipidemic diet. Both statin treatments significantly influenced the markers studied. Nevertheless, rosuvastatin administration resulted in a greater reduction in MYD88, NF-kB, chemokines (CCL4, CCL20, and CCR2), and interleukins IL-1β, IL-8, KLF4, NANOG, and HIF1α than fluvastatin. Fluvastatin, on the other hand, led to a stronger decrease in IL-4. Downregulation of IL-2 and IL-18 and upregulation of IFNβ and HOXA5 were comparable between the two statins. Notably, rosuvastatin had a stronger effect on the upregulation of klotho and IL-10. Conclusion: Overall, statin therapy significantly attenuated inflammatory, pluripotency, and klotho expression in myocardial tissue under atherogenic conditions. Our findings also highlight the differential efficacy of rosuvastatin over fluvastatin in curtailing proatherogenic inflammation, which could have profound implications for the clinical management of cardiovascular disease.

Differential gene expression of Wharton's jelly-derived mesenchymal cells mediated by graphene oxide in basal and osteo-induced media.

Graphene oxide (GO) is widespread in scaffold engineering owing to its extraordinary properties such as multiple oxygen functional groups, high hydrophilicity ability and biocompatibility. It is known to promote differentiation in mesenchymal stem cells, but concomitant comparison of its modulation on the expression profiles of Wharton's jelly (WJ)-MSC surface markers, lineage differentiation, and epigenetic regulatory genes in basal and induced condition are still lacking. Unraveling the fundamental mechanisms is essential for the effective utilization of WJ-MSCs incorporated with GO in therapy. This study aims to explore the unique gene expression profiles and epigenetic characteristics of WJ-MSCs influenced by GO. The characterized GO-coated coverslip served as a substrate for culturing WJ-MSCs. In addition to investigating the impact of GO on cell proliferation and differentiation, we conducted a gene expression study using PCR array, while epigenetic control was assessed through bisulfite sequencing and Western blot analysis. Our findings indicate that the presence of GO maintained the proliferation and survival of WJ-MSCs. In the absence of induction, GO led to minor lipid and glycosaminoglycan deposition in WJ-MSCs. This was evidenced by the sustained expression of pluripotency and lineage-specific genes, demethylation at the OCT4 promoter, and a decrease in H3K9 methylation. In osteo-induced condition, the occurrence of osteogenesis appeared to be guided by BMP/TGF and ERK pathway activation, accompanied by the upregulation of osteogenic-related genes and downregulation of DNMT3b. GO in osteo-induced condition create a favorable microenvironment that promotes the osteogenesis of WJ-MSCs by influencing genetic and epigenetic controls. This helps in advancing our knowledge on the use of GO as priming platform and WJ-MSCs an alternate source for bone repair and regeneration.

Deterministic nuclear reprogramming of mammalian nuclei to a totipotency-like state by Amphibian meiotic oocytes for stem cell therapy in humans.

The ultimate aim of nuclear reprogramming is to provide stem cells or differentiated cells from unrelated cell types as a cell source for regenerative medicine. A popular route towards this is transcription factor induction, and an alternative way is an original procedure of transplanting a single somatic cell nucleus to an unfertilized egg. A third route is to transplant hundreds of cell nuclei into the germinal vesicle (GV) of a non-dividing Amphibian meiotic oocyte, which leads to the activation of silent genes in 24 h and robustly induces a totipotency-like state in almost all transplanted cells. We apply this third route for potential therapeutic use and describe a procedure by which the differentiated states of cells can be reversed so that totipotency and pluripotency gene expression are regained. Differentiated cells are exposed to GV extracts and are reprogrammed to form embryoid bodies, which shows the maintenance of stemness and could be induced to follow new directions of differentiation. We conclude that much of the reprogramming effect of eggs is already present in meiotic oocytes and does not require cell division or selection of dividing cells. Reprogrammed cells by oocytes could serve as replacements for defective adult cells in humans.

MiR-290 Family Maintains Pluripotency and Self-Renewal by Regulating MAPK Signaling Pathway in Intermediate Pluripotent Stem Cells.

Mouse embryonic stem cells (ESCs) and epiblast stem cells (EpiSCs) are derived from pre- and post-implantation embryos, representing the initial "naïve" and final "primed" states of pluripotency, respectively. In this study, novel reprogrammed pluripotent stem cells (rPSCs) were induced from mouse EpiSCs using a chemically defined medium containing mouse LIF, BMP4, CHIR99021, XAV939, and SB203580. The rPSCs exhibited domed clones and expressed key pluripotency genes, with both X chromosomes active in female cells. Furthermore, rPSCs differentiated into cells of all three germ layers in vivo through teratoma formation. Regarding epigenetic modifications, the DNA methylation of Oct4, Sox2, and Nanog promoter regions and the mRNA levels of Dnmt3a, Dnmt3b, and Dnmt1 were reduced in rPSCs compared with EpiSCs. However, the miR-290 family was significantly upregulated in rPSCs. After removing SB203580, an inhibitor of the p38 MAPK pathway, the cell colonies changed from domed to flat, with a significant decrease in the expression of pluripotency genes and the miR-290 family. Conversely, overexpression of pri-miR-290 reversed these changes. In addition, Map2k6 was identified as a direct target gene of miR-291b-3p, indicating that the miR-290 family maintains pluripotency and self-renewal in rPSCs by regulating the MAPK signaling pathway.

Generation of induced pluripotent stem cell line, NIMHi009-A, from PBMCs of an adult healthy male

Human induced pluripotent stem cells provide an exceptional platform for studying pathogenesis in vitro. We, therefore, have generated and characterized human induced pluripotent stem cell (iPSC) line NIMHi009-A derived from peripheral blood mononuclear cells (PBMCs) of healthy adult male control for an epileptic patient carrying voltage gated sodium channel mutation, using Sendai virus-based reprogramming. The generated iPSCs express pluripotency genes and can spontaneously differentiate into three germ layers. These cells display a normal karyotype and are free of mycoplasma. The iPSC line NIMHi009-A can be used as healthy control for modelling various diseases and screening for drugs.

Adipose Tissue and Umbilical Cord Tissue: Potential Sources of Mesenchymal Stem Cells for Liver Fibrosis Treatment

Purpose of the studyMesenchymal stem cells (MSCs) are potential alternatives for liver fibrosis treatment; however, their optimal sources remain uncertain. This study compares the ex-vivo expansion characteristics of MSCs obtained from adipose tissue (AT) and umbilical cord (UC) and assesses their therapeutic potential for liver fibrosis treatment. MethodsSince MSCs from early to mid-passage numbers (P2–P6) are preferable for cellular therapy, we investigated the growth kinetics of AT-MSCs and UC-MSCs up to P6 and evaluated their therapeutic effects in a rat model of liver fibrosis induced by diethylnitrosamine. ResultsResults from the expansion studies demonstrated that both cell types exhibited bonafide characteristics of MSCs, including surface antigens, pluripotent gene expression, and differentiation potential. However, AT-MSCs demonstrated a shorter doubling time (58.2 ± 7.3 vs. 82.3 ± 4.3 h; p < 0.01) and a higher population doubling level (10.1 ± 0.7 vs. 8.2 ± 0.3; p < 0.01) compared to UC-MSCs, resulting in more cellular yield (230 ± 9.0 vs. 175 ± 13.2 million) in less time. Animal studies demonstrated that both MSC types significantly reduced liver fibrosis (p < 0.05 vs. the control group) while also improving liver function and downregulating fibrosis-associated gene expression. ConclusionAT-MSCs and UC-MSCs effectively reduce liver fibrosis. However, adipose cultures display an advantage by yielding a higher number of MSCs in a shorter duration, rendering them a viable choice for scenarios requiring immediate single-dose administration, often encountered in clinical settings.

Tumor suppressor let-7 acts as a key regulator for pluripotency gene expression in Muse cells

In embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), the expression of an RNA-binding pluripotency-relevant protein, LIN28, and the absence of its antagonist, the tumor-suppressor microRNA (miRNA) let-7, play a key role in maintaining pluripotency. Muse cells are non-tumorigenic pluripotent-like stem cells residing in the bone marrow, peripheral blood, and organ connective tissues as pluripotent surface marker SSEA-3(+). They express pluripotency genes, differentiate into triploblastic-lineage cells, and self-renew at the single cell level. Muse cells do not express LIN28 but do express let-7 at higher levels than in iPSCs. In Muse cells, we demonstrated that let-7 inhibited the PI3K-AKT pathway, leading to sustainable expression of the key pluripotency regulator KLF4 as well as its downstream genes, POU5F1, SOX2, and NANOG. Let-7 also suppressed proliferation and glycolysis by inhibiting the PI3K-AKT pathway, suggesting its involvement in non-tumorigenicity. Furthermore, the MEK/ERK pathway is not controlled by let-7 and may have a pivotal role in maintaining self-renewal and suppression of senescence. The system found in Muse cells, in which the tumor suppressor let-7, but not LIN28, tunes the expression of pluripotency genes, might be a rational cell system conferring both pluripotency-like properties and a low risk for tumorigenicity.

Molecular characterization of an iPSC line derived from a patient with cone‐rod dystrophy related to a mutation in the PROM1 gene

Aims/Purpose: The PROM1 gene encodes the protein Prominin‐1, which plays a crucial role in the morphogenesis of photoreceptor outer segments. The c.1354dupT mutation, associated with various inherited retinal diseases (IRD) phenotypes, leads to a premature stop codon. This study aimed to assess the silencing efficiency of reprogramming vectors and the expression of endogenous pluripotency genes in the iPSC line [DCB]‐FiPSC1‐Ep5F‐2.Methods: The iPSC line [DCB]‐FiPSC1‐Ep5F‐2 was generated from a patient with Cone‐rod dystrophy (CRD) linked to the c.1354dupT mutation in the PROM1 gene. iPSC colonies were stained using alkaline phosphatase (AP) blue membrane substrate. The c.1354dupT mutation was Sanger sequenced. To confirm the absence of episomal vector integration, quantitative PCR (qPCR) targeting a region common to all reprogramming vectors (within the EBNA1 gene) was conducted. Vector‐specific primer‐based quantitative reverse transcription PCR (qRT‐PCR) was used to assess the expression of reprogramming genes from the episomal vectors. Additionally, qRT‐PCR with gene‐specific primers was utilized to evaluate the expression of endogenous pluripotency genes. Untransfected fibroblasts served as the negative control, while fibroblasts transfected with the episomal vectors 72 h earlier were used as the positive control.Results: The iPSC line [DCB]‐FiPSC1‐Ep5F‐2 exhibited positive AP activity. The presence of the c.1354dupT mutation was confirmed. Furthermore, the number of copies of the EBNA1 gene was significantly lower in the generated iPSC line compared to the control. The relative mRNA expression of the reprogramming vectors was also significantly lower in the iPSC line, while the relative mRNA expression of the endogenous pluripotency genes was significantly higher than in the control.Conclusions: While further immunocytochemical characterization is necessary to fully ascertain iPSC pluripotency, the patient‐derived iPSC line [DCB]‐FiPSC1‐Ep5F‐2 shows promise as a disease model for personalized therapy development.

Immunohistochemical characterization of pluripotency of an iPSC line derived from a patient with cone‐rod dystrophy related to a mutation in the PROM1 gene

Purpose: PROM1 gene encodes the protein Prominin‐1 which plays a critical role in the morphogenesis of photoreceptors outer segments. The c.1354dupT mutation in PROM1 causes a premature stop codon and it has been related with different inherited retinal diseases (IRD) phenotypes. The aim of this study was to demonstrate the expression of key pluripotency genes by studying protein transcription factors and surface markers on the iPSC line [DCB]‐FiPSC1‐Ep5F‐2.Methods: Our group generated the iPSC line [DCB]‐FiPSC1‐Ep5F‐2 from a patient with Cone‐rod dystrophy (CRD) related to the mutation c.1354dupT in the PROM1 gene. iPSC was grown on matrigel coated 15 μ‐slide 8‐well culture plates and fixed with 10% formalin solution. Plates were washed with Tris Buffered Saline and blocked (0.3%Triton X‐100 and 3%Donkey serum) for 60 min. Then, different combinations of primary antibodies related to pluripotency (OCT4, SSEA3, SOX2, SSEA4, TRA1‐60, NANOG and TRA1‐81) were incubated at 4°C overnight. Afterwards, species‐specific secondary antibodies were conjugated and immunostaining with DAPI was used. Finally, the samples were evaluated by confocal microscopy.Results: Immunofluorescence analysis of the iPSC line [DCB]‐FiPSC1‐Ep5F‐2 revealed the expression of the common embryonic stem cell markers such as the transcription factors OCT4, NANOG and SOX2, and the surface markers SSEA3, TRA‐1‐81, SSEA4 and TRA‐1‐60. Transcriptional markers stain cell nuclei, while surface markers stain cell membranes showing that iPSCs have the potential for pluripotency and multilineage differentiation.Conclusions: Although molecular characterization is necessary to completely elucidate iPSC pluripotency and bank this line in an international depository, the [DCB]‐FiPSC1‐Ep5F‐2 patient derived iPSC line could be useful as a disease model for the development of personalized therapies.

Generation of human induced pluripotent stem cell lines derived from three Noonan syndrome patients from a single family carrying the heterozygous PTPN11 c.188 A > G (p.Y63C) mutation

We have established Noonan syndrome (NS)-derived induced pluripotent stem cell (iPSC) lines derived from peripheral blood mononuclear cells (PBMCs) of a family cohort carrying the heterozygous PTPN11 c.188 A > G (p.Y63C) mutation. The new iPSC lines were validated by confirming the normal karyotype and targeted mutation, the pluripotent gene expression, and the differentiation capacity into three germ layers.

Establishment of Capra hircus somatic cells and induction of pluripotent stem-like cells.

Capra hircus (goat) induced pluripotent stem cells (giPSCs) harbor enormous scientific value and contribute to cellular agriculture, animal cloning, etc. Conventional approaches to giPSC generation suffer from complexity and low preparation efficiency. In the present study, we introduced the episomal vectors carrying the human pluripotent genes in goat somatic cells to generate the giPSC-like colonies. Initially, a simple non-enzymatic method was used to isolate the goat dermal fibroblast cells and, further, a cell line was established. Later, goat fibroblast cells were transfected with commercially available episomal vectors carrying the human pluripotent genes and successfully generated the iPSC-like colonies which exhibited the expression of goat endogenous pluripotent genes and positive staining with alkaline phosphatase. Moreover, giPS-like cells formed embryoid bodies (EBs)-like aggregates and weekly expressed the marker genes of two germ layers. Reprogramming of goat fibroblast using episomal vectors carrying human pluripotent genes could lead to the development of an efficient and time- and cost-effective approach to giPSC generation.

Investigation on Electrospun and Solvent-Casted PCL-PLGA Blends Scaffolds Embedded with Induced Pluripotent Stem Cells for Tissue Engineering.

The design, production, and characterisation of tissue-engineered scaffolds made of polylactic-co-glycolic acid (PLGA), polycaprolactone (PCL) and their blends obtained through electrospinning (ES) or solvent casting/particulate leaching (SC) manufacturing techniques are presented here. The polymer blend composition was chosen to always obtain a prevalence of one of the two polymers, in order to investigate the contribution of the less concentrated polymer on the scaffolds' properties. Physical-chemical characterization of ES scaffolds demonstrated that tailoring of fibre diameter and Young modulus (YM) was possible by controlling PCL concentration in PLGA-based blends, increasing the fibre diameter from 0.6 to 1.0 µm and reducing the YM from about 22 to 9 MPa. SC scaffolds showed a "bubble-like" topography, caused by the porogen spherical particles, which is responsible for decreasing the contact angles from about 110° in ES scaffolds to about 74° in SC specimens. Nevertheless, due to phase separation within the blend, solvent-casted samples displayed less reproducible properties. Furthermore, ES samples were characterised by 10-fold higher water uptake than SC scaffolds. The scaffolds suitability as iPSCs culturing support was evaluated using XTT assay, and pluripotency and integrin gene expression were investigated using RT-PCR and RT-qPCR. Thanks to their higher wettability and appropriate YM, SC scaffolds seemed to be superior in ensuring high cell viability over 5 days, whereas the ability to maintain iPSCs pluripotency status was found to be similar for ES and SC scaffolds.

The thyroid hormone enhances mouse embryonic fibroblasts reprogramming to pluripotent stem cells: role of the nuclear receptor corepressor 1.

Pluripotent stem cells can be generated from somatic cells by the Yamanaka factors Oct4, Sox2, Klf4 and c-Myc. Mouse embryonic fibroblasts (MEFs) were transduced with the Yamanaka factors and generation of induced pluripotent stem cells (iPSCs) was assessed by formation of alkaline phosphatase positive colonies, pluripotency gene expression and embryod bodies formation. The thyroid hormone triiodothyronine (T3) enhances MEFs reprogramming. T3-induced iPSCs resemble embryonic stem cells in terms of the expression profile and DNA methylation pattern of pluripotency genes, and of their potential for embryod body formation and differentiation into the three major germ layers. T3 induces reprogramming even though it increases expression of the cyclin kinase inhibitors p21 and p27, which are known to oppose acquisition of pluripotency. The actions of T3 on reprogramming are mainly mediated by the thyroid hormone receptor beta and T3 can enhance iPSC generation in the absence of c-Myc. The hormone cannot replace Oct4 on reprogramming, but in the presence of T3 is possible to obtain iPSCs, although with low efficiency, without exogenous Klf4. Furthermore, depletion of the corepressor NCoR (or Nuclear Receptor Corepressor 1) reduces MEFs reprogramming in the absence of the hormone and strongly decreases iPSC generation by T3 and also by 9cis-retinoic acid, a well-known inducer of reprogramming. NCoR depletion also markedly antagonizes induction of pluripotency gene expression by both ligands. Inclusion of T3 on reprogramming strategies has a potential use in enhancing the generation of functional iPSCs for studies of cell plasticity, disease and regenerative medicine.

Divergent Roles of KLF4 During Primordial Germ Cell Fate Induction from Human Embryonic Stem Cells.

As a core transcriptional factor regulating pluripotency, Krüppel-like factor 4 (KLF4) has gained much attention in the field of stem cells during the past decades. However, few research have focused on the function of KLF4 during human primordial germ cell (PGC) specification. Here, we induced human PGC-like cells (hPGCLCs) from human embryonic stem cells (hESCs) and the derived hPGCLCs upregulated PGC-related genes, like SOX17, BLIMP1, TFAP2C, NANOS3, and the naïve pluripotency gene KLF4. The KLF4-knockout hESCs formed typical multicellular colonies with clear borders, expressed pluripotency genes, such as NANOG, OCT4, and SOX2, and exhibited no differences in proliferation capacity compared with wild type hESCs. Notably, KLF4 deletion in hESCs did not influence the induction of PGCLCs in vitro. In contrast, overexpression of KLF4 during PGC induction process inhibited the efficiency of PGCLC formation from hESCs in vitro. Overexpression of KLF4 may regenerate the naïve ground state in hESCs and results in repression for PGC specification. Thus, KLF4 could be a downstream target of human PGC program and the upregulation of KLF4 is prepared for late stage of germline development.

BRD9-mediated control of the TGF-β/Activin/Nodal pathway regulates self-renewal and differentiation of human embryonic stem cells and progression of cancer cells.

Bromodomain-containing protein 9 (BRD9) is a specific subunit of the non-canonical SWI/SNF (ncBAF) chromatin-remodeling complex, whose function in human embryonic stem cells (hESCs) remains unclear. Here, we demonstrate that impaired BRD9 function reduces the self-renewal capacity of hESCs and alters their differentiation potential. Specifically, BRD9 depletion inhibits meso-endoderm differentiation while promoting neural ectoderm differentiation. Notably, supplementation of NODAL, TGF-β, Activin A or WNT3A rescues the differentiation defects caused by BRD9 loss. Mechanistically, BRD9 forms a complex with BRD4, SMAD2/3, β-CATENIN and P300, which regulates the expression of pluripotency genes and the activity of TGF-β/Nodal/Activin and Wnt signaling pathways. This is achieved by regulating the deposition of H3K27ac on associated genes, thus maintaining and directing hESC differentiation. BRD9-mediated regulation of the TGF-β/Activin/Nodal pathway is also demonstrated in the development of pancreatic and breast cancer cells. In summary, our study highlights the crucial role of BRD9 in the regulation of hESC self-renewal and differentiation, as well as its participation in the progression of pancreatic and breast cancers.

Effect of Hyperbaric Oxygen and Inflammation on Human Gingival Mesenchymal Stem/Progenitor Cells.

The present study explores for the first time the effect of hyperbaric oxygen (HBO) on gingival mesenchymal stem cells' (G-MSCs) gene expression profile, intracellular pathway activation, pluripotency, and differentiation potential under an experimental inflammatory setup. G-MSCs were isolated from five healthy individuals (n = 5) and characterized. Single (24 h) or double (72 h) HBO stimulation (100% O2, 3 bar, 90 min) was performed under experimental inflammatory [IL-1β (1 ng/mL)/TNF-α (10 ng/mL)/IFN-γ (100 ng/mL)] and non-inflammatory micro-environment. Next Generation Sequencing and KEGG pathway enrichment analysis, G-MSCs' pluripotency gene expression, Wnt-/β-catenin pathway activation, proliferation, colony formation, and differentiation were investigated. G-MSCs demonstrated all mesenchymal stem/progenitor cells' characteristics. The beneficial effect of a single HBO stimulation was evident, with anti-inflammatory effects and induction of differentiation (TLL1, ID3, BHLHE40), proliferation/cell survival (BMF, ID3, TXNIP, PDK4, ABL2), migration (ABL2) and osteogenic differentiation (p < 0.05). A second HBO stimulation at 72 h had a detrimental effect, significantly increasing the inflammation-induced cellular stress and ROS accumulation through HMOX1, BHLHE40, and ARL4C amplification and pathway enrichment (p < 0.05). Results outline a positive short-term single HBO anti-inflammatory, regenerative, and differentiation stimulatory effect on G-MSCs. A second (72 h) stimulation is detrimental to the same properties. The current results could open new perspectives in the clinical application of short-termed HBO induction in G-MSCs-mediated periodontal reparative/regenerative mechanisms.

Maternal exposure to hyperbaric oxygen at the preimplantation stages increases apoptosis and ectopic Cdx2 expression and decreases Oct4 expression in mouse blastocysts via Nrf2-Notch1 upregulation and Nf2 downregulation.

The environmental oxygen tension has been reported to impact the blastocyst quality and cell numbers in the inner cell mass (ICM) during human and murine embryogenesis. While the molecular mechanisms leading to increased ICM cell numbers and pluripotency gene expression under hypoxia have been deciphered, it remains unknown which regulatory pathways caused the underweight fetal body and overweight placenta after maternal exposure to hyperbaric oxygen (HBO). The blastocysts from the HBO-exposed pregnant mice revealed significantly increased signals of reactive oxygen species (ROS) and nuclear Nrf2 staining, decreased Nf2 and Oct4 expression, increased nuclear Tp53bp1 and active caspase-3 staining, and ectopic nuclear signals of Cdx2, Yap, and the Notch1 intracellular domain (N1ICD) in the ICM. In the ICM of the HBO-exposed blastocysts, both Nf2 cDNA microinjection and Nrf2 shRNA microinjection significantly decreased the ectopic nuclear expression of Cdx2, Tp53bp1, and Yap whereas increased Oct4 expression, while Nrf2 shRNA microinjection also significantly decreased Notch1 mRNA levels and nuclear expression of N1ICD and active caspase-3. We show for the first time that maternal exposure to HBO at the preimplantation stage induces apoptosis and impairs ICM cell specification via upregulating Nrf2-Notch1-Cdx2 expression and downregulating Nf2-Oct4 expression.

Generation of human induced pluripotent stem cell line (MUi033-A) from a male with homozygous for Hemoglobin E

Hemoglobin E (HbE), a common variant in Southeast Asian populations, results from a G to A substitution at codon 26 of the HBB gene, causing abnormal Hb and mild β-thalassemia-like symptoms. Here, we derived an induced pluripotent stem cell (iPSC) line, named MUi033-A, from a male homozygous for HbE. The iPSC line demonstrates a normal karyotype and embryonic stem cell-like properties including pluripotency gene expression, and tri-lineage differentiation potential. This iPSC resource holds the potential for investigating gene therapy targeting HbE mutation.

Signalling pathway crosstalk stimulated by L-proline drives mouse embryonic stem cells to primitive-ectoderm-like cells.

The amino acid L-proline exhibits growth factor-like properties during development - from improving blastocyst development to driving neurogenesis in vitro. Addition of 400 μM L-proline to self-renewal medium drives naïve mouse embryonic stem cells (ESCs) to early primitive ectoderm-like (EPL) cells - a transcriptionally distinct primed or partially primed pluripotent state. EPL cells retain expression of pluripotency genes, upregulate primitive ectoderm markers, undergo a morphological change and have increased cell number. These changes are facilitated by a complex signalling network hinging on the Mapk, Fgfr, Pi3k and mTor pathways. Here, we use a factorial experimental design coupled with statistical modelling to understand which signalling pathways are involved in the transition between ESCs and EPL cells, and how they underpin changes in morphology, cell number, apoptosis, proliferation and gene expression. This approach reveals pathways which work antagonistically or synergistically. Most properties were affected by more than one inhibitor, and each inhibitor blocked specific aspects of the naïve-to-primed transition. These mechanisms underpin progression of stem cells across the in vitro pluripotency continuum and serve as a model for pre-, peri- and post-implantation embryogenesis.