scholarly journals Transient Downregulation of Nanog and Oct4 Induced by DETA/NO Exposure in Mouse Embryonic Stem Cells Leads to Mesodermal/Endodermal Lineage Differentiation

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Sergio Mora-Castilla ◽  
Juan R. Tejedo ◽  
Rafael Tapia-Limonchi ◽  
Irene Díaz ◽  
Ana B. Hitos ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Histone H3 ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Directed Differentiation ◽  
Lineage Differentiation ◽  
Induction Of Differentiation ◽  
Differentiating Agent ◽  
Pluripotency Genes

The function of pluripotency genes in differentiation is a matter of investigation. We report here that Nanog and Oct4 are reexpressed in two mouse embryonic stem cell (mESC) lines following exposure to the differentiating agent DETA/NO. Both cell lines express a battery of both endoderm and mesoderm markers following induction of differentiation with DETA/NO-based protocols. Confocal analysis of cells undergoing directed differentiation shows that the majority of cells expressing Nanog express also endoderm genes such as Gata4 and FoxA2 (75.4% and 96.2%, resp.). Simultaneously, mRNA of mesodermal markers Flk1 and Mef2c are also regulated by the treatment. Acetylated histone H3 occupancy at the promoter of Nanog is involved in the process of reexpression. Furthermore, Nanog binding to the promoter of Brachyury leads to repression of this gene, thus disrupting mesendoderm transition.

scholarly journals Mof-associated complexes have overlapping and unique roles in regulating pluripotency in embryonic stem cells and during differentiation

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Sarina Ravens ◽  
Marjorie Fournier ◽  
Tao Ye ◽  
Matthieu Stierle ◽  
Doulaye Dembele ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Transcription Regulation ◽  
Histone Acetyltransferase ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Individual Contribution ◽  
Genome Wide Analysis ◽  
Genome Wide ◽  
The Individual

The histone acetyltransferase (HAT) Mof is essential for mouse embryonic stem cell (mESC) pluripotency and early development. Mof is the enzymatic subunit of two different HAT complexes, MSL and NSL. The individual contribution of MSL and NSL to transcription regulation in mESCs is not well understood. Our genome-wide analysis show that i) MSL and NSL bind to specific and common sets of expressed genes, ii) NSL binds exclusively at promoters, iii) while MSL binds in gene bodies. Nsl1 regulates proliferation and cellular homeostasis of mESCs. MSL is the main HAT acetylating H4K16 in mESCs, is enriched at many mESC-specific and bivalent genes. MSL is important to keep a subset of bivalent genes silent in mESCs, while developmental genes require MSL for expression during differentiation. Thus, NSL and MSL HAT complexes differentially regulate specific sets of expressed genes in mESCs and during differentiation.

scholarly journals Epsins Regulate Mouse Embryonic Stem Cell Exit from Pluripotency and Neural Commitment by Controlling Notch Activation

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Marina Cardano ◽  
Jacopo Zasso ◽  
Luca Ruggiero ◽  
Giuseppina Di Giacomo ◽  
Matteo Marcatili ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Embryonic Stem Cells ◽  
Notch Signaling ◽  
Neural Differentiation ◽  
Radial Glia ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Neural Progenitors ◽  
Notch Activation

Epsins are part of the internalization machinery pivotal to control clathrin-mediated endocytosis. Here, we report that epsin family members are expressed in mouse embryonic stem cells (mESCs) and that epsin1/2 knockdown alters both mESC exits from pluripotency and their differentiation. Furthermore, we show that epsin1/2 knockdown compromises the correct polarization and division of mESC-derived neural progenitors and their conversion into expandable radial glia-like neural stem cells. Finally, we provide evidence that Notch signaling is impaired following epsin1/2 knockdown and that experimental restoration of Notch signaling rescues the epsin-mediated phenotypes. We conclude that epsins contribute to control mESC exit from pluripotency and allow their neural differentiation by appropriate modulation of Notch signaling.

scholarly journals Asymptomatic neurotoxicity of amyloid β-peptides (Aβ1-42 and Aβ25-35) on mouse embryonic stem cell-derived neural cells

2020 ◽  
Author(s):  
Nur Izzati Mansor ◽  
Carolindah Makena Ntimi ◽  
Noraishah Mydin Abdul-Aziz ◽  
King-Hwa Ling ◽  
Aishah Adam ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Stem Cells ◽  
Stem Cell ◽  
Embryonic Stem Cell ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Neural Cells ◽  
Aβ Peptides ◽  
Intracellular Ros

One of the strategies in the establishment of in vitro oxidative stress models for neurodegenerative diseases, such as Alzheimer’s disease (AD), is to induce neurotoxicity by amyloid beta (Aβ) peptides in suitable neural cells. Presently, data on the neurotoxicity of Aβ in neural cells differentiated from stem cells are limited. In this study, we attempted to induce oxidative stress in transgenic 46C mouse embryonic stem cell-derived neurons via treatment with Ab peptides (Aβ1-42 and Aβ25-35). 46C neural cells were generated by promoting the formation of multicellular aggregates, embryoid bodies (EBs) in the absence of leukemia inhibitory factor (LIF), followed by the addition of all-trans retinoic acid (ATRA) as the neural inducer. Mature neuronal cells were exposed to different concentrations of Aβ1-42 and Aβ25-35 for 24 h. Morphological changes, cell viability, and intracellular ROS production were assessed. We found that 100 µM Aβ1-42 and 50 µM Aβ25-35 only promoted 40% and 10%, respectively, of cell injury and death in the 46C-derived neuronal cells. Interestingly, treatment with each of the Aβ peptides resulted in a significant increase of intracellular ROS activity, as compared to untreated neurons. These findings indicate the potential of using neurons derived from stem cells and Aβ peptides in generating oxidative stress for the establishment of an in vitro AD model that could be useful for drug screening and natural product studies.

scholarly journals Non-canonical TAF complexes regulate active promoters in human embryonic stem cells

eLife ◽  
2012 ◽  
Vol 1 ◽  
Author(s):  
Glenn A Maston ◽  
Lihua Julie Zhu ◽  
Lynn Chamberlain ◽  
Ling Lin ◽  
Minggang Fang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Human Embryonic Stem Cells ◽  
Embryonic Stem ◽  
General Transcription Factor ◽  
Promoter Occupancy ◽  
Induction Of Differentiation ◽  
Tata Box Binding Protein ◽  
Pluripotency Genes ◽  
Active Genes

The general transcription factor TFIID comprises the TATA-box-binding protein (TBP) and approximately 14 TBP-associated factors (TAFs). Here we find, unexpectedly, that undifferentiated human embryonic stem cells (hESCs) contain only six TAFs (TAFs 2, 3, 5, 6, 7 and 11), whereas following differentiation all TAFs are expressed. Directed and global chromatin immunoprecipitation analyses reveal an unprecedented promoter occupancy pattern: most active genes are bound by only TAFs 3 and 5 along with TBP, whereas the remaining active genes are bound by TBP and all six hESC TAFs. Consistent with these results, hESCs contain a previously undescribed complex comprising TAFs 2, 6, 7, 11 and TBP. Altering the composition of hESC TAFs, either by depleting TAFs that are present or ectopically expressing TAFs that are absent, results in misregulated expression of pluripotency genes and induction of differentiation. Thus, the selective expression and use of TAFs underlies the ability of hESCs to self-renew.

Abstract T P89: Curcumin Encapsulated Stem Cell Exosomes Attenuate Ischemic Brain Injury in Type 1 Diabetic Akita Mice

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Anuradha Kalani ◽  
Pradip K Kamat ◽  
Neetu Tyagi
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cognitive Functions ◽  
Infarct Volume ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Auditory Brainstem ◽  
Brainstem Response ◽  
Akita Mice

Background and Purpose: Stroke in type-1 diabetes mellitus (T1DM) is severe in terms of exacerbated brain damage and severe functional decline as compared to non-diabetic stroke. Curcumin possesses remarkable medicinal properties and stem cells exosomes (nano-vesicles; 40-100 nm) have paracrine effects with neovascularization properties. The therapy available for stroke (tissue plasminogen activator) is not effective in diabetic stroke and leads to excessive vasodilation and hemorrhagic transformations. Therefore, we tested the hypothesis that encapsulating curcumin to mouse embryonic stem cell exosomes mitigates type-1 diabetic stroke injury. Methods: We employed 8-10 weeks old male genetic T1DM Ins2+/- Akita mice. Ischemia was performed for 40 min and reperfusion for 7 days in the following mice groups: 1) Sham Akita , 2) Sham Akita + cur-exo , 3) IR Akita , 4) IR Akita + cur-exo . Exosomes were isolated from mouse embryonic stem cells culture conditioned media and encapsulated with curcumin ( cur-exo ). Therapeutic exo-cur units were used for mice treatment intranasally for 7 days. Brain cryo-sections were analyzed for vascular (VCAM, VE-cadherin), glial (GFAP), neuronal (Tuj1, nNOS) coupling in ipsilateral area. Neuronal loss, neurodegeneration was analyzed with NeuN, fluorojade-C staining. White matter damage was examined with luxol fast blue. Intra-carotid FITC-BSA infusion was used to assess venular leakage. Passive avoidance and auditory brainstem response tests were used to determine cognitive functions. Results: Treatment with cur-exo alleviated Infarct volume, edema, and vascular damage in IR Akita + cur-exo mice as compared to IR Akita mice. The axonal-glia damage and venular permeability were exacerbated in IR Akita mice, as compared to sham Akita , which were mitigated after cur-exo treatment. Cur-exo also ameliorated neurodegeneration and promoted neuronal survival as determined through immunolocalization studies. Further, cur-exo remarkably restored cognitive functions (p<0.001, n=6). Conclusion: Our results suggested that combining the therapeutic efficacy of curcumin and stem cells exosomes represent a novel treatment for stroke during T1DM. Acknowledgement: This work was supported by NIH grant HL107640.

HMGA1, a Factor Enriched in Hematopoietic Stem Cells, Embryonic Stem Cells, and Hematologic Malignancy, Enhances Cellular Reprogramming to a Pluripotent Stem-Like Cell.

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2323-2323
Author(s):  
Linda Resar ◽  
Sandeep N Shah ◽  
Candace Kerr ◽  
Leslie Cope ◽  
Elias Zambidis ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cancer Cells ◽  
Embryonic Stem ◽  
Cellular Reprogramming ◽  
Transcriptional Networks ◽  
Hematopoietic Stem ◽  
Stem Cell State ◽  
Pluripotency Genes

Abstract Abstract 2323 Although recent studies have identified genes important in hematopoietic stem cells (HSCs), human embryonic stem cells (hESCs), and induced pluripotent stem cells (iPSCs), the molecular underpinnings of normal stem cell function are unclear. A better understanding of key stem cell pathways will be essential for the safe use of stem cells in regenerative medicine and should also uncover novel therapeutic targets in aggressive hematologic malignancies and other stem-like cancer cells. To elucidate the molecular underpinnings of “stemness”, we investigated transcriptional networks in pluripotent stem cells. Our focus is the high mobility group A1 (HMGA1) gene, which encodes the HMGA1a and HMGA1b chromatin remodeling proteins. These proteins bind to AT-rich regions of DNA and orchestrate the assembly of transcription factor complexes to alter chromatin structure and modulate gene expression. HMGA1 is highly expressed during embryogenesis with low or undetectable levels in adult, differentiated tissues. HMGA1 is also enriched in HSCs, hESCs, iPSCs, refractory leukemia, and poorly differentiated solid tumors. Our group discovered that HMGA1 functions as a potent oncogene in cultured cells and causes aggressive leukemia in transgenic mice. We also found that high levels of HMGA1 expression correlate with relapse in acute lymphoblastic leukemia. Together, these findings suggest that HMGA1 drives a stem cell phenotype during normal development, hematopoiesis, and malignant transformation. To further investigate the role of HMGA1 in a stem cell state, we compared its expression in iPSCs, hESCs, HSCs, and cancer cells. HMGA1 is highly expressed in fully reprogrammed iPSCs and hESCs, with intermediate levels in HSCs and cancer cells, and low levels in fibroblasts. When hESCs are induced to differentiate, HMGA1 decreases and parallels that of other pluripotency factors. Conversely, forced expression of HMGA1 blocks differentiation in hESCs. We also discovered that HMGA1 enhances cellular reprogramming of somatic cells (mesenchymal stem cells, HSCs, and fetal lung fibroblasts) to an iPSC together with the Yamanaka factors (OCT4, SOX2, KLF4, cMYC or OSKM). HMGA1 results in an increase in the number and size of iPSC colonies compared to OSKM controls. Surprisingly, there was normal differentiation in vitro and benign, teratoma formation in vivo of the HMGA1-derived iPSCs. During the reprogramming process, HMGA1 induces the expression of pluripotency genes, including SOX2, LIN28, and cMYC, while knockdown of HMGA1 in hESCs results in the repression of these genes. Chromatin immunoprecipitation shows that HMGA1 binds to the promoters of these pluripotency genes in vivo. In summary, our findings uncover a key role for HMGA1 as a regulator of the stem cell state through transcriptional networks that induce pluripotency and an undifferentiated state. Further studies are needed to determine if HMGA1 pathways could be targeted in hematologic and other malignancies or exploited in regenerative medicine. Disclosures: No relevant conflicts of interest to declare.

Effects of mitogens on proliferation of mouse embryonic stem cell-derived neural stem cells

2010 ◽  
Vol 68 ◽  
pp. e244
Author(s):  
Takuya Yoshie ◽  
Masahiro Otsu ◽  
Hiroyuki Omori ◽  
Masayoshi Shibata ◽  
Risa Ueda ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Neural Stem Cells ◽  
Embryonic Stem Cell ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell

scholarly journals Nicotinamide restricts neural precursor proliferation to enhance catecholaminergic neuronal subtype differentiation from mouse embryonic stem cells

2020 ◽  
Author(s):  
Síle M. Griffin ◽  
Mark R. Pickard ◽  
Clive P. Hawkins ◽  
Adrian C. Williams ◽  
Rosemary A. Fricker
Keyword(s):  
Stem Cells ◽  
Cell Proliferation ◽  
Stem Cell ◽  
Tyrosine Hydroxylase ◽  
Cell Cultures ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Neural Progenitors ◽  
Neuronal Populations ◽  
Regenerative Therapies

AbstractEmerging evidence indicates that a strong relationship exists between brain regenerative therapies and nutrition. Early life nutrition plays an important role during embryonic brain development, and there are clear consequences to an imbalance in nutritional factors on both the production and survival of mature neuronal populations and the infant’s risk of diseases in later life. Our research and that of others suggest that vitamins play a fundamental role in the formation of neurons and their survival. There is a growing body of evidence that nicotinamide, the water-soluble amide form of vitamin B3, is implicated in the conversion of pluripotent stem cells to clinically relevant cells for regenerative therapies. This study investigated the ability of nicotinamide to promote the development of mature catecholaminergic neuronal populations (associated with Parkinson’s disease) from mouse embryonic stem cells, as well as investigating the underlying mechanisms of nicotinamide’s action.Nicotinamide selectively enhanced the production of tyrosine hydroxylase-expressing neurons and serotonergic neurons from mouse embryonic stem cell cultures (Sox1GFP knock-in 46C cell line). A 5-Ethynyl-2’-deoxyuridine (EdU) assay ascertained that nicotinamide, when added in the initial phase, reduced cell proliferation. Nicotinamide drove tyrosine hydroxylase-expressing neuron differentiation as effectively as an established cocktail of signalling factors, reducing the proliferation of neural progenitors and accelerating neuronal maturation, neurite outgrowth and neurotransmitter expression.These novel findings show that nicotinamide enhanced and enriched catecholaminergic differentiation and inhibited cell proliferation by directing cell cycle arrest in mouse embryonic stem cell cultures, thus driving a critical neural proliferation-to-differentiation switch from neural progenitors to neurons. Further research into the role of vitamin metabolites in embryogenesis will significantly advance cell-based regenerative medicine, and help realize their role as crucial developmental signalling molecules in brain development.

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