Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 258
Filtrar
2.
Cell Stem Cell ; 29(3): 400-418.e13, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35143761

RESUMO

Totipotent cells have more robust developmental potency than any other cell types, giving rise to both embryonic and extraembryonic tissues. Stable totipotent cell cultures and deciphering the principles of totipotency regulation would be invaluable to understand cell plasticity and lineage segregation in early development. Our approach of remodeling the pericentromeric heterochromatin and re-establishing the totipotency-specific broad H3K4me3 domains promotes the pluri-to-totipotency transition. Our protocol establishes a closer match of mouse 2-cell (2C) embryos than any other 2C-like cells. These totipotent-like stem cells (TLSCs) are stable in culture and possess unique molecular features of the mouse 2C embryo. Functionally, TLSCs are competent for germline transmission and give rise to both embryonic and extraembryonic lineages at high frequency. Therefore, TLSCs represent a highly valuable cell type for studies of totipotency and embryology.


Assuntos
Montagem e Desmontagem da Cromatina , Células-Tronco Totipotentes , Animais , Diferenciação Celular , Plasticidade Celular , Cromatina/metabolismo , Embrião de Mamíferos , Camundongos
3.
Nat Commun ; 12(1): 4856, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381034

RESUMO

Totipotent cells have the ability to generate embryonic and extra-embryonic tissues. Interestingly, a rare population of cells with totipotent-like potential, known as 2 cell (2C)-like cells, has been identified within ESC cultures. They arise from ESC and display similar features to those found in the 2C embryo. However, the molecular determinants of 2C-like conversion have not been completely elucidated. Here, we show that the CCCTC-binding factor (CTCF) is a barrier for 2C-like reprogramming. Indeed, forced conversion to a 2C-like state by the transcription factor DUX is associated with DNA damage at a subset of CTCF binding sites. Depletion of CTCF in ESC efficiently promotes spontaneous and asynchronous conversion to a 2C-like state and is reversible upon restoration of CTCF levels. This phenotypic reprogramming is specific to pluripotent cells as neural progenitor cells do not show 2C-like conversion upon CTCF-depletion. Furthermore, we show that transcriptional activation of the ZSCAN4 cluster is necessary for successful 2C-like reprogramming. In summary, we reveal an unexpected relationship between CTCF and 2C-like reprogramming.


Assuntos
Fator de Ligação a CCCTC/metabolismo , Reprogramação Celular , Células-Tronco Totipotentes/citologia , Animais , Sítios de Ligação , Fator de Ligação a CCCTC/genética , Morte Celular , Dano ao DNA , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Camundongos , Células-Tronco Totipotentes/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Dev Cell ; 56(12): 1697-1699, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34157304

RESUMO

Totipotency refers to single cells' developmental capacity to form an entire organism. Understanding how totipotent stem cells form has implications for chimera generation. In a recent Cell study, Shen et al. (2021) report that inhibition of spliceosomes resets conventional pluripotent stem cells to a cellular state with totipotency features.


Assuntos
Células-Tronco Embrionárias , Células-Tronco Pluripotentes , Processamento Alternativo/genética , Diferenciação Celular , Células-Tronco Totipotentes
5.
Sci Rep ; 11(1): 11167, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045607

RESUMO

In multicellular organisms, oocytes and sperm undergo fusion during fertilization and the resulting zygote gives rise to a new individual. The ability of zygotes to produce a fully formed individual from a single cell when placed in a supportive environment is known as totipotency. Given that totipotent cells are the source of all multicellular organisms, a better understanding of totipotency may have a wide-ranging impact on biology. The precise delineation of totipotent cells in mammals has remained elusive, however, although zygotes and single blastomeres of embryos at the two-cell stage have been thought to be the only totipotent cells in mice. We now show that a single blastomere of two- or four-cell mouse embryos can give rise to a fertile adult when placed in a uterus, even though blastomere isolation disturbs the transcriptome of derived embryos. Single blastomeres isolated from embryos at the eight-cell or morula stages and cultured in vitro manifested pronounced defects in the formation of epiblast and primitive endoderm by the inner cell mass and in the development of blastocysts, respectively. Our results thus indicate that totipotency of mouse zygotes extends to single blastomeres of embryos at the four-cell stage.


Assuntos
Blastômeros/citologia , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário/fisiologia , Células-Tronco Totipotentes/citologia , Zigoto/citologia , Animais , Blastocisto/citologia , Técnicas de Cultura Embrionária , Camundongos
6.
Nat Struct Mol Biol ; 28(6): 521-532, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34045724

RESUMO

Totipotent cells hold enormous potential for regenerative medicine. Thus, the development of cellular models recapitulating totipotent-like features is of paramount importance. Cells resembling the totipotent cells of early embryos arise spontaneously in mouse embryonic stem (ES) cell cultures. Such '2-cell-like-cells' (2CLCs) recapitulate 2-cell-stage features and display expanded cell potential. Here, we used 2CLCs to perform a small-molecule screen to identify new pathways regulating the 2-cell-stage program. We identified retinoids as robust inducers of 2CLCs and the retinoic acid (RA)-signaling pathway as a key component of the regulatory circuitry of totipotent cells in embryos. Using single-cell RNA-seq, we reveal the transcriptional dynamics of 2CLC reprogramming and show that ES cells undergo distinct cellular trajectories in response to RA. Importantly, endogenous RA activity in early embryos is essential for zygotic genome activation and developmental progression. Overall, our data shed light on the gene regulatory networks controlling cellular plasticity and the totipotency program.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Totipotentes/citologia , Tretinoína/fisiologia , Acitretina/farmacologia , Animais , Massa Celular Interna do Blastocisto/citologia , Diferenciação Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Feminino , Redes Reguladoras de Genes/genética , Genes Reporter , Isotretinoína/farmacologia , Masculino , Camundongos/embriologia , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Piperazinas/farmacologia , Pirazóis/farmacologia , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/farmacologia , RNA-Seq , Receptores do Ácido Retinoico/antagonistas & inibidores , Receptores do Ácido Retinoico/fisiologia , Transdução de Sinais/efeitos dos fármacos , Células-Tronco Totipotentes/efeitos dos fármacos , Transcrição Genética , Tretinoína/antagonistas & inibidores , Tretinoína/farmacologia
7.
Nat Cell Biol ; 23(1): 49-60, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33420491

RESUMO

Totipotency is the ability of a single cell to give rise to all of the differentiated cell types that build the conceptus, yet how to capture this property in vitro remains incompletely understood. Defining totipotency relies on a variety of assays of variable stringency. Here, we describe criteria to define totipotency. We explain how distinct criteria of increasing stringency can be used to judge totipotency by evaluating candidate totipotent cell types in mice, including early blastomeres and expanded or extended pluripotent stem cells. Our data challenge the notion that expanded or extended pluripotent states harbour increased totipotent potential relative to conventional embryonic stem cells under in vitro and in vivo conditions.


Assuntos
Blastômeros/citologia , Diferenciação Celular , Linhagem da Célula/genética , Embrião de Mamíferos/citologia , Células-Tronco Embrionárias/citologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Totipotentes/citologia , Animais , Blastômeros/metabolismo , Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias/metabolismo , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Masculino , Camundongos , Células-Tronco Pluripotentes/metabolismo , Análise de Célula Única , Células-Tronco Totipotentes/metabolismo
8.
Nature ; 589(7840): 110-115, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33239785

RESUMO

In mammals, telomere protection is mediated by the essential protein TRF2, which binds chromosome ends and ensures genome integrity1,2. TRF2 depletion results in end-to-end chromosome fusions in all cell types that have been tested so far. Here we find that TRF2 is dispensable for the proliferation and survival of mouse embryonic stem (ES) cells. Trf2-/- (also known as Terf2) ES cells do not exhibit telomere fusions and can be expanded indefinitely. In response to the deletion of TRF2, ES cells exhibit a muted DNA damage response that is characterized by the recruitment of γH2AX-but not 53BP1-to telomeres. To define the mechanisms that control this unique DNA damage response in ES cells, we performed a CRISPR-Cas9-knockout screen. We found a strong dependency of TRF2-null ES cells on the telomere-associated protein POT1B and on the chromatin remodelling factor BRD2. Co-depletion of POT1B or BRD2 with TRF2 restores a canonical DNA damage response at telomeres, resulting in frequent telomere fusions. We found that TRF2 depletion in ES cells activates a totipotent-like two-cell-stage transcriptional program that includes high levels of ZSCAN4. We show that the upregulation of ZSCAN4 contributes to telomere protection in the absence of TRF2. Together, our results uncover a unique response to telomere deprotection during early development.


Assuntos
Células-Tronco Pluripotentes/metabolismo , Telômero/metabolismo , Proteína 2 de Ligação a Repetições Teloméricas/deficiência , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo , Animais , Proliferação de Células , Sobrevivência Celular , Dano ao DNA , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Pluripotentes/citologia , Proteína 2 de Ligação a Repetições Teloméricas/genética , Células-Tronco Totipotentes/citologia , Células-Tronco Totipotentes/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
9.
Development ; 147(16)2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32847824

RESUMO

Embryonic stem cells (ESCs) are derived from the pre-implantation mammalian blastocyst. At this point in time, the newly formed embryo is concerned with the generation and expansion of both the embryonic lineages required to build the embryo and the extra-embryonic lineages that support development. When used in grafting experiments, embryonic cells from early developmental stages can contribute to both embryonic and extra-embryonic lineages, but it is generally accepted that ESCs can give rise to only embryonic lineages. As a result, they are referred to as pluripotent, rather than totipotent. Here, we consider the experimental potential of various ESC populations and a number of recently identified in vitro culture systems producing states beyond pluripotency and reminiscent of those observed during pre-implantation development. We also consider the nature of totipotency and the extent to which cell populations in these culture systems exhibit this property.


Assuntos
Blastocisto/metabolismo , Linhagem da Célula , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Totipotentes/metabolismo , Animais , Blastocisto/citologia , Células-Tronco Embrionárias Humanas/citologia , Humanos , Células-Tronco Totipotentes/citologia
10.
Plant Reprod ; 33(3-4): 143-158, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32651727

RESUMO

KEY MESSAGE: In vitro embryo development is highly plastic; embryo cell fate can be re-established in tissue culture through different pathways. In most angiosperms, embryo development from the single-celled zygote follows a defined pattern of cell divisions in which apical (embryo proper) and basal (root and suspensor) cell fates are established within the first cell divisions. By contrast, embryos that are induced in vitro in the absence of fertilization show a less regular initial cell division pattern yet develop into histodifferentiated embryos that can be converted into seedlings. We used the Brassica napus microspore embryogenesis system, in which the male gametophyte is reprogrammed in vitro to form haploid embryos, to identify the developmental fates of the different types of embryogenic structures found in culture. Using time-lapse imaging of LEAFY COTYLEDON1-expressing cells, we show that embryogenic cell clusters with very different morphologies are able to form haploid embryos. The timing of surrounding pollen wall (exine) rupture is a major determinant of cell fate in these clusters, with early exine rupture leading to the formation of suspensor-bearing embryos and late rupture to suspensorless embryos. In addition, we show that embryogenic callus, which develops into suspensor-bearing embryos, initially expresses transcripts associated with both basal- and apical-embryo cell fates, suggesting that these two cell fates are fixed later in development. This study reveals the inherent plasticity of in vitro embryo development and identifies new pathways by which embryo cell fate can be established.


Assuntos
Brassica napus , Sementes , Brassica napus/anatomia & histologia , Brassica napus/embriologia , Brassica napus/genética , Plasticidade Celular , Haploidia , Pólen , Sementes/anatomia & histologia , Células-Tronco Totipotentes/citologia
11.
Int J Mol Sci ; 21(12)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545519

RESUMO

Plants are sessile organisms that have a remarkable developmental plasticity, which ensures their optimal adaptation to environmental stresses. Plant cell totipotency is an extreme example of such plasticity, whereby somatic cells have the potential to form plants via direct shoot organogenesis or somatic embryogenesis in response to various exogenous and/or endogenous signals. Protoplasts provide one of the most suitable systems for investigating molecular mechanisms of totipotency, because they are effectively single cell populations. In this review, we consider the current state of knowledge of the mechanisms that induce cell proliferation from individual, differentiated somatic plant cells. We highlight initial explant metabolic status, ploidy level and isolation procedure as determinants of successful cell reprogramming. We also discuss the importance of auxin signalling and its interaction with stress-regulated pathways in governing cell cycle induction and further stages of plant cell totipotency.


Assuntos
Células do Mesofilo/citologia , Protoplastos/citologia , Células-Tronco Totipotentes/citologia , Diferenciação Celular , Proliferação de Células , Reprogramação Celular , Fenômenos Fisiológicos Vegetais , Ploidias , Transdução de Sinais
12.
J Genet Genomics ; 47(3): 123-130, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32305172

RESUMO

Embryonic stem cells possess fascinating capacity of self-renewal and developmental potential, leading to significant progress in understanding the molecular basis of pluripotency, disease modeling, and reprogramming technology. Recently, 2-cell-like embryonic stem cells (ESCs) and expanded potential stem cells or extended pluripotent stem cells (EPSCs) generated from early-cleavage embryos display some features of totipotent embryos. These cell lines provide valuable in vitro models to study underlying principles of totipotency, cell plasticity, and lineage segregation. In this review, we summarize the current progress in this filed and highlight the application potentials of these cells in the future.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Células-Tronco Embrionárias/citologia , Células-Tronco Totipotentes/citologia , Linhagem da Célula/genética , Plasticidade Celular/genética , Autorrenovação Celular/genética , Humanos
13.
Philos Trans R Soc Lond B Biol Sci ; 375(1795): 20190339, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32075562

RESUMO

Our perception of the role of the previously considered 'selfish' or 'junk' DNA has been dramatically altered in the past 20 years or so. A large proportion of this non-coding part of mammalian genomes is repetitive in nature, classified as either satellites or transposons. While repetitive elements can be termed selfish in terms of their amplification, such events have surely been co-opted by the host, suggesting by itself a likely altruistic function for the organism at the subject of such natural selection. Indeed numerous examples of transposons regulating the functional output of the host genome have been documented. Transposons provide a powerful framework for large-scale relatively rapid concerted regulatory activities with the ability to drive evolution. Mammalian totipotency has emerged as one key stage of development in which transposon-mediated regulation of gene expression has taken centre stage in the past few years. During this period, large-scale (epigenetic) reprogramming must be accomplished in order to activate the host genome. In mice and men, one particular element murine endogenous retrovirus with leucine tRNA primer (MERVL) (and its counterpart human ERVL (HERVL)) appears to have acquired roles as a key driving force in this process. Here, I will discuss and interpret the current knowledge and its implications regarding the role of transposons, particularly of long interspersed nuclear elements (LINE-1s) and endogenous retroviruses (ERVs), in the regulation of totipotency. This article is part of a discussion meeting issue 'Crossroads between transposons and gene regulation'.


Assuntos
Elementos de DNA Transponíveis/genética , Mamíferos/genética , Células-Tronco Totipotentes/metabolismo , Animais , Mamíferos/metabolismo , Seleção Genética
14.
Cell Rep ; 30(1): 25-36.e6, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31914391

RESUMO

Known as a histone H3K9 methyltransferase, SETDB1 is essential for embryonic development and pluripotent inner cell mass (ICM) establishment. However, its function in pluripotency regulation remains elusive. In this study, we find that under the "ground state" of pluripotency with two inhibitors (2i) of the MEK and GSK3 pathways, Setdb1-knockout fails to induce trophectoderm (TE) differentiation as in serum/LIF (SL), indicating that TE fate restriction is not the direct target of SETDB1. In both conditions, Setdb1-knockout activates a group of genes targeted by SETDB1-mediated H3K9 methylation, including Dux. Notably, Dux is indispensable for the reactivation of 2C-like state genes upon Setdb1 deficiency, delineating the mechanistic role of SETDB1 in totipotency restriction. Furthermore, Setdb1-null ESCs maintain pluripotent marker (e.g., Nanog) expression in the 2i condition. This "ground state" Setdb1-null population undergoes rapid cell death by activating Ripk3 and, subsequently, RIPK1/RIPK3-dependent necroptosis. These results reveal the essential role of Setdb1 between totipotency and pluripotency transition.


Assuntos
Linhagem da Célula , Histona-Lisina N-Metiltransferase/metabolismo , Células-Tronco Pluripotentes/metabolismo , Trofoblastos/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Ectoderma/metabolismo , Técnicas de Inativação de Genes , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Proteína Homeobox Nanog/metabolismo , Necroptose , Células-Tronco Pluripotentes/citologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Células-Tronco Totipotentes/metabolismo
15.
Development ; 146(24)2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31767620

RESUMO

The murine developing epicardium heterogeneously expresses the transcription factors TCF21 and WT1. Here, we show that this cell heterogeneity is conserved in human epicardium, regulated by BNC1 and associated with cell fate and function. Single cell RNA sequencing of epicardium derived from human pluripotent stem cells (hPSC-epi) revealed that distinct epicardial subpopulations are defined by high levels of expression for the transcription factors BNC1 or TCF21. WT1+ cells are included in the BNC1+ population, which was confirmed in human foetal hearts. THY1 emerged as a membrane marker of the TCF21 population. We show that THY1+ cells can differentiate into cardiac fibroblasts (CFs) and smooth muscle cells (SMCs), whereas THY1- cells were predominantly restricted to SMCs. Knocking down BNC1 during the establishment of the epicardial populations resulted in a homogeneous, predominantly TCF21high population. Network inference methods using transcriptomic data from the different cell lineages derived from the hPSC-epi delivered a core transcriptional network organised around WT1, TCF21 and BNC1. This study unveils a list of epicardial regulators and is a step towards engineering subpopulations of epicardial cells with selective biological activities.


Assuntos
Linhagem da Célula/genética , Proteínas de Ligação a DNA/fisiologia , Pericárdio/citologia , Células-Tronco Pluripotentes/fisiologia , Fatores de Transcrição/fisiologia , Diferenciação Celular/genética , Células Cultivadas , Feminino , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/fisiologia , Pericárdio/metabolismo , Células-Tronco Pluripotentes/citologia , Gravidez , Cultura Primária de Células , Células-Tronco Totipotentes/citologia , Células-Tronco Totipotentes/fisiologia
16.
Nat Cell Biol ; 21(7): 835-844, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209294

RESUMO

Totipotency refers to the ability of a cell to generate all of the cell types of an organism. Unlike pluripotency, the establishment of totipotency is poorly understood. In mouse embryonic stem cells, Dux drives a small percentage of cells into a totipotent state by expressing 2-cell-embryo-specific transcripts. To understand how this transition takes place, we performed single-cell RNA-seq, which revealed a two-step transcriptional reprogramming process characterized by downregulation of pluripotent genes in the first step and upregulation of the 2-cell-embryo-specific elements in the second step. To identify factors controlling the transition, we performed a CRISPR-Cas9-mediated screen, which revealed Myc and Dnmt1 as two factors preventing the transition. Mechanistic studies demonstrate that Myc prevents downregulation of pluripotent genes in the first step, while Dnmt1 impedes 2-cell-embryo-specific gene activation in the second step. Collectively, the findings of our study reveal insights into the establishment and regulation of the totipotent state in mouse embryonic stem cells.


Assuntos
Reprogramação Celular/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , Células-Tronco Embrionárias/metabolismo , Genes myc/genética , Animais , Diferenciação Celular/genética , Epigênese Genética/genética , Camundongos , Células-Tronco Embrionárias Murinas , Células-Tronco Pluripotentes/citologia , Células-Tronco Totipotentes/citologia
17.
Nat Cell Biol ; 21(6): 671-673, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160707
18.
Bioethics ; 33(6): 644-652, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31135064

RESUMO

In contrast to embryo donation, the permissibility of 2PN cell donation is highly controversial in Germany. This article is based on there being a legal loophole with respect to 2PN cell donation, which results from an inconsistency within the Embryo Protection Act on the normative status of 2PN cells. Following that thesis, the article argues that, on the basis of the normative criterion totipotency (i.e. the capacity to develop into a born human being), 2PN cells should also be considered human embryos within the meaning of the Act and thereby be protected by that Act in the same way as embryos. However, the normative assumption that 2PN cells should already be endowed with human dignity and the right to life has absurd consequences. Moreover, the consistent continuation of the Embryo Protection Act, as well as of the underlying ethical position or argumentation (i.e. the potentiality argument), leads to the even more absurd consequence of having to place every human somatic cell under the protection of human dignity and the right to life. As totipotency or the developmental potential therefore cannot delimit entities considered worthy of protection (i.e. human embryos) from entities considered not worthy of protection (i.e. 2PN cells, gametes, hESC, hiPSC and human somatic cells), it is not a suitable normative criterion. As a paradigmatic case, 2PN cell donation demonstrates that by retaining this normative criterion the now obsolete German Embryo Protection (Act) ultimately undermines itself.


Assuntos
Destinação do Embrião/ética , Destinação do Embrião/legislação & jurisprudência , Células-Tronco Embrionárias Humanas , Células-Tronco Pluripotentes Induzidas , Células-Tronco Totipotentes , Zigoto/citologia , Alemanha , Humanos , Pessoalidade , Valor da Vida
19.
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1056832

RESUMO

Abstract Objective: To investigate the regeneration of rat's salivary gland diabetic defect after intraglandular transplantation of Human Dental Pulp Stem Cells (HDPSCs) on acinar cell vacuolization and Interleukin-10 (IL-10). Material and Methods: HDPSCs isolated from the dental pulp of first premolars #34. HDPSCs from the 3rd passage was characterized by immunocytochemistry of CD73, CD90, CD105 and CD45. Twenty-four male Wistar rats, 3-month-old, 250-300 grams induced with Streptozotocin 30 mg/kg body weight to create diabetes mellitus (DM) divided into 4 groups (n=6); positive control group on Day-7; positive control group on Day-14; treatment group Day-7 (DM+5.105HDPSCs); treatment group on Day-14. On Day-7 and Day-14, rats were sacrificed. Histopathological examination performed to analyze acinar cells vacuolization while Enzyme-linked Immunoabsorbent Assay to measure IL-10 serum level. Data obtained were analyzed statistically using multiple comparisons Bonferroni test, Kruskal Wallis, Shapiro-Wilk and Levene's test result Results: The highest acinar cell vacuolization found in control group Day 14 (0.239 ± 0.132), meanwhile the lowest acinar cell vacuolization found in treatment group Day 7 (0.019 ± 0.035) with significant difference (p=0.003). The highest IL-10 serum level found in treatment group Day 14 (175.583 ± 120.075) with significant difference (p=0.001) Conclusion: Transplantation of HDPSC was able to regenerate submandibular salivary gland defects in diabetic rats by decreasing acinar cell vacuolization and slightly increase IL-10 serum level.


Assuntos
Animais , Ratos , Interleucina-10 , Ratos Wistar , Células-Tronco Totipotentes , Diabetes Mellitus , Células Acinares , Glândulas Salivares , Células-Tronco , Imuno-Histoquímica/instrumentação , Estatísticas não Paramétricas , Polpa Dentária , Indonésia
20.
Bioessays ; 40(10): e1800107, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30151860

RESUMO

The acoel worm Symsagittifera roscoffensis, an early offshoot of the Bilateria and the only well-studied marine acoel that lives in a photosymbiotic relationship, exhibits a centralized nervous system, brain regeneration, and a wide repertoire of complex behaviors such as circatidal rhythmicity, photo/geotaxis, and social interactions. While this animal can be collected by the thousands and is studied historically, significant progress is made over the last decade to develop it as an emerging marine model. The authors here present the feasibility of culturing it in the laboratory and describe the progress made on different areas, including genomic and tissue architectures, highlighting the associated challenges. In light of these developments, and on the ability to access abundant synchronized embryos, the authors put forward S. roscoffensis as a marine system to revisit questions in the areas of photosymbiosis, regeneration, chronobiology, and the study of complex behaviors from a molecular and evolutionary perspective.


Assuntos
Encéfalo/fisiologia , Platelmintos/fisiologia , Regeneração/fisiologia , Animais , Organismos Aquáticos , Comportamento Animal , Encéfalo/citologia , Fenômenos Cronobiológicos , Ritmo Circadiano/genética , Microalgas/fisiologia , Microbiota/fisiologia , Compostos de Sulfônio/metabolismo , Simbiose , Células-Tronco Totipotentes/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...