Astroglia genesis in vitro: distinct effects of retinoic acid in different phases of neural stem cell differentiation.

Institute of Experimental Medicine of Hungarian Academy of Sciences, Budapest, Hungary.
International journal of developmental neuroscience: the official journal of the International Society for Developmental Neuroscience (Impact Factor: 2.92). 07/2009; 27(4):365-75. DOI: 10.1016/j.ijdevneu.2009.02.004
Source: PubMed

ABSTRACT In the developing CNS, the manifestation of the macro-glial phenotypes is delayed behind the formation of neurons. The "neurons first--glia second" principle seems to be valid for neural tissue differentiation throughout the neuraxis, but the reasons behind are far from clear. In the presented study, the mechanisms of this timing were investigated in vitro, in the course of the neural differentiation of one cell derived NE-4C neuroectodermal stem and P19 embryonic carcinoma cells. The data demonstrated that astrocyte formation coincided in time with the maturation of postmitotic neurons, but the close vicinity of neurons did not initiate astrocyte formation before schedule. All-trans retinoic acid, a well-known inducer of neuronal differentiation, on the other hand, blocked effectively the astroglia production if present in defined stages of the in vitro neuroectodermal cell differentiation. According to the data, retinoic acid plays at least a dual role in astrogliogenesis: while it is needed for committing neural progenitors for a future production of astrocytes, it prevents premature astrogliogenesis by inhibiting the differentiation of primed glial progenitors.


Available from: Zsu Környei, Jun 03, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Retinoic acid as one of the most important regulators for cell differentiation was examined in this study for differentiation of human umbilical mesenchymal cells (hUCM). After isolation, hUCM were evaluated for mesenchymal stem cell properties by flow cytometry and alkaline phosphatase assay. Also, doubling time of the cells and their differentiation potential into adipogenic and osteogenic cells were tested. hUCM were then cultured with different concentrations of retinoic acid, and on days 1, 7, and 12, the percentage of differentiated cells was determined by immunostaining for nestin, anti-microtubule associated protein 2 (MAP2), glutamic acid decarboxylase (GAD), and gamma-aminobutyric acid (GABA) markers. The isolated cells were negative for the hematopoietic markers and positive for the mesenchymal markers. They showed the population doubling time 60 ± 3 hours and differentiated into osteogenic and adipogenic cells. A descending trend in nestin and an ascending trend in MAP2, GAD, and GABA expression were observed from the first day until the last day between different concentrations of retinoic acid. hUCM cells may have the potential to differentiate into neural cells in the presence of different incubation period and concentration of retinoic acid.
    Iranian biomedical journal 04/2015; 19(2):82-90.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Many neural disorders are characterized by the loss of one or several types of neural cells. Human umbilical cord-derived mesenchymal cells (hUCMs) are capable of differentiating into neuron, astroglia-like and oligodendrocyte cell types. However, a reliable means of inducing the selective differentiation of hUCMs into neural cells in vitro has not yet been established. For induction of neural differentiation, hUCMs were seeded onto sterile glass slides and six various cocktails using a base medium (DMEM/LG) supplemented with 10 % FBS, retinoic acid (RA), dimethyl sulfoxide (DMSO), epidermal growth factor (EGF) and fibroblast growth factor (FGF) were used to compare their effect on neuronal, astrocyte and oligodandrocyte differentiation. The hUCMs were positive for mesenchymal markers, while they were negative for hematopoietic markers. Differentiation to adipogenic and osteogenic lineage was detected in these cells. Our data revealed that the cocktail consisting of DMEM/LG, FBS, RA, FGF, and EGF (DF/R/Fg/E group) induced hUCM cells to express the highest percentage of nestin, ß-tubulin III, neurofilament, and CNPase. The DF/Ds/Fg/E group led to the highest percentage of GFAP expression. While the expression levels of NF, GFAP, and CNPase were the lowest in the DF group. The least percentage of nestin and ß-tubulin III expression was observed in the DF/Ds group. We may conclude that FGF and EGF are important inducers for differentiation of hUCMs into neuron, astrocyte and oligodendrocyte. RA can induce hUCMs to differentiate into neuron and oligodendrocyte while for astrocyte differentiation DMSO had a pivotal role.
    Cytotechnology 10/2014; 67(3). DOI:10.1007/s10616-014-9703-6 · 1.45 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Multipotent neural stem cells (NSCs) are currently under investigation as a candidate treatment for central nervous system (CNS) injury because of their potential to compensate for neuronal damage and to reconstruct disrupted neuronal connections. To maximize the regenerative effect of the derived neurons and to minimize the side effects of the derived astrocytes, it is necessary to regulate the fate determination of NSCs to produce more neurons and fewer astrocytes. Both valproic acid (VPA) and all-trans-retinoic acid (ATRA), two clinically established drugs, induce neuronal differentiation and facilitate neurite outgrowth at the expense of astrocytic differentiation in NSCs. However, the time-dependent activities and the long-term treatment effects of these drugs have not been explored in NSCs. More importantly, the efficacies of VPA and ATRA in neuronal promotion and astrocytic suppression remain unclear. In this study, we compare the time-dependent characteristics of VPA and ATRA in NSC differentiation and neurite outgrowth in vitro and, for the first time, demonstrate the improved efficacy of their combined application in neuronal induction and astrocytic suppression. These significant effects are closely coupled to the altered expression of a neurogenic transcription factor, a Wnt signaling component, a cell cycle regulator and a neural growth factor, indicating an underlying cross-talk between the mechanisms of action of ATRA and VPA. These findings indicate that a novel strategy combining these two therapeutic drugs may improve the restorative effect of NSC transplantation by altering the expression of their interconnected targets for fate determination. Copyright © 2014. Published by Elsevier B.V.
    Brain Research 11/2014; DOI:10.1016/j.brainres.2014.11.029 · 2.83 Impact Factor