1
|
Everlien I, Yen TY, Liu YC, Di Marco B, Vázquez-Marín J, Centanin L, Alfonso J, Monyer H. Diazepam binding inhibitor governs neurogenesis of excitatory and inhibitory neurons during embryonic development via GABA signaling. Neuron 2022; 110:3139-3153.e6. [PMID: 35998632 DOI: 10.1016/j.neuron.2022.07.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 05/05/2022] [Accepted: 07/25/2022] [Indexed: 11/29/2022]
Abstract
Of the neurotransmitters that influence neurogenesis, gamma-aminobutyric acid (GABA) plays an outstanding role, and GABA receptors support non-synaptic signaling in progenitors and migrating neurons. Here, we report that expression levels of diazepam binding inhibitor (DBI), an endozepine that modulates GABA signaling, regulate embryonic neurogenesis, affecting the long-term outcome regarding the number of neurons in the postnatal mouse brain. We demonstrate that DBI is highly expressed in radial glia and intermediate progenitor cells in the germinal zones of the embryonic mouse brain that give rise to excitatory and inhibitory cells. The mechanism by which DBI controls neurogenesis involves its action as a negative allosteric modulator of GABA-induced currents on progenitor cells that express GABAA receptors containing γ2 subunits. DBI's modulatory effect parallels that of GABAA-receptor-mediating signaling in these cells in the proliferative areas, reflecting the tight control that DBI exerts on embryonic neurogenesis.
Collapse
Affiliation(s)
- Isabelle Everlien
- Department of Clinical Neurobiology at the German Cancer Research Center (DKFZ) and the Medical Faculty of the Heidelberg University, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Ting-Yun Yen
- Department of Clinical Neurobiology at the German Cancer Research Center (DKFZ) and the Medical Faculty of the Heidelberg University, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Taiwan International Graduate Program in Molecular Medicine, National Yang Ming Chiao Tung University and Academia Sinica, Taipei, Taiwan
| | - Yu-Chao Liu
- Department of Clinical Neurobiology at the German Cancer Research Center (DKFZ) and the Medical Faculty of the Heidelberg University, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Barbara Di Marco
- Department of Clinical Neurobiology at the German Cancer Research Center (DKFZ) and the Medical Faculty of the Heidelberg University, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Javier Vázquez-Marín
- Center for Organismal Studies, Heidelberg University, Im Neuenheimer Feld 230, Heidelberg 69120, Germany
| | - Lázaro Centanin
- Center for Organismal Studies, Heidelberg University, Im Neuenheimer Feld 230, Heidelberg 69120, Germany
| | - Julieta Alfonso
- Department of Clinical Neurobiology at the German Cancer Research Center (DKFZ) and the Medical Faculty of the Heidelberg University, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Hannah Monyer
- Department of Clinical Neurobiology at the German Cancer Research Center (DKFZ) and the Medical Faculty of the Heidelberg University, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
| |
Collapse
|
2
|
Effect of developmental lead exposure on neurogenesis and cortical neuronal morphology in Wistar rats. Toxicol Ind Health 2018; 34:665-678. [DOI: 10.1177/0748233718781283] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Lead (Pb) is a neurotoxic heavy metal that largely affects the developing nervous system. The present study examined the temporal effect of perinatal Pb exposure on neurogenesis and cortical neuronal morphology. Wistar pregnant rats were exposed to 0.5% lead acetate throughout pregnancy and to postnatal day (PD) 28. Offspring were grouped as gestational day (GD) 18 and 21 and PD 7, 14, 21, and 28 in both control and experimental groups. Brain sections were processed for immunohistological staining with anti-proliferating cell nuclear antigen (PCNA) or glial fibrillary acidic protein (GFAP). Brains from 14, 21, and 28 PDs pups were processed for Golgi–Cox stain. Pb exposure significantly increased PCNA-positive nuclei in the ventricular and subventricular zones of the lateral ventricle at 18 and 21 GDs. Postnatally, the Pb-treated groups showed a significant decrease in PCNA-positivity and neuron density compared to control. This reduction was associated with an increase in damaged or apoptotic cell profiles in the experimental groups. At PD 21, there was a significant increase in GFAP immunoreactivity in Pb-exposed groups compared with control. Furthermore, the total apical and basal dendritic length of pyramidal neurons in layer 2–3 of the Golgi–Cox stained sensorimotor cortex was comparable in both control and Pb-exposed groups. Spine density per 10 µm was significantly increased at PD 14 and 21 on the apical dendrites but not basal dendrites of Pb-treated groups. In conclusion, developmental Pb exposure in rats induces a toxic effect on neurogenesis and on cortical neurons, which may be related to cognitive disabilities observed in children exposed to lead.
Collapse
|
3
|
Levav-Rabkin T, Melamed O, Clarke G, Farber M, Cryan JF, Dinan TG, Grossman Y, Golan HM. A sensitive period of mice inhibitory system to neonatal GABA enhancement by vigabatrin is brain region dependent. Neuropsychopharmacology 2010; 35:1138-54. [PMID: 20043003 PMCID: PMC3055404 DOI: 10.1038/npp.2009.219] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 11/09/2009] [Accepted: 12/02/2009] [Indexed: 01/21/2023]
Abstract
Neurodevelopmental disorders, such as schizophrenia and autism, have been associated with disturbances of the GABAergic system in the brain. We examined immediate and long-lasting influences of exposure to the GABA-potentiating drug vigabatrin (GVG) on the GABAergic system in the hippocampus and cerebral cortex, before and during the developmental switch in GABA function (postnatal days P1-7 and P4-14). GVG induced a transient elevation of GABA levels. A feedback response to GABA enhancement was evident by a short-term decrease in glutamate decarboxylase (GAD) 65 and 67 levels. However, the number of GAD65/67-immunoreactive (IR) cells was greater in 2-week-old GVG-treated mice. A long-term increase in GAD65 and GAD67 levels was dependent on brain region and treatment period. Vesicular GABA transporter was insensitive to GVG. The overall effect of GVG on the Cl(-) co-transporters NKCC1 and KCC2 was an enhancement of their synthesis, which was dependent on the treatment period and brain region studied. In addition, a short-term increase was followed by a long-term decrease in KCC2 oligomerization in the cell membrane of P4-14 hippocampi and cerebral cortices. Analysis of the Ca(2+) binding proteins expressed in subpopulations of GABAergic cells, parvalbumin and calbindin, showed region-specific effects of GVG during P4-14 on parvalbumin-IR cell density. Moreover, calbindin levels were elevated in GVG mice compared to controls during this period. Cumulatively, these results suggest a particular susceptibility of the hippocampus to GVG when exposed during days P4-14. In conclusion, our studies have identified modifications of key components in the inhibitory system during a critical developmental period. These findings provide novel insights into the deleterious consequences observed in children following prenatal and neonatal exposure to GABA-potentiating drugs.
Collapse
Affiliation(s)
- Tamar Levav-Rabkin
- Faculty of Health Sciences, Department of Developmental Molecular Genetics, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Osnat Melamed
- Faculty of Health Sciences, Department of Developmental Molecular Genetics, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Gerard Clarke
- Department of Psychiatry, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Malca Farber
- Faculty of Health Sciences, Department of Developmental Molecular Genetics, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - John F Cryan
- Department of Pharmacology and Therapeutics, School of Pharmacy and Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- Department of Psychiatry, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Yoram Grossman
- Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Faculty of Health Sciences, Department of Physiology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Hava M Golan
- Faculty of Health Sciences, Department of Developmental Molecular Genetics, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| |
Collapse
|
4
|
Isayama RN, Leite PEC, Lima JPM, Uziel D, Yamasaki EN. Impact of ethanol on the developing GABAergic system. Anat Rec (Hoboken) 2010; 292:1922-39. [PMID: 19943346 DOI: 10.1002/ar.20966] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Alcohol intake during pregnancy has a tremendous impact on the developing brain. Embryonic and early postnatal alcohol exposures have been investigated experimentally to elucidate the fetal alcohol spectrum disorders' (FASD) milieu, and new data have emerged to support a devastating effect on the GABAergic system in the adult and developing nervous system. GABA is a predominantly inhibitory neurotransmitter that during development excites neurons and orchestrates several developmental processes such as proliferation, migration, differentiation, and synaptogenesis. This review summarizes and brings new data on neurodevelopmental aspects of the GABAergic system with FASD in experimental telencephalic models.
Collapse
Affiliation(s)
- Ricardo Noboro Isayama
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | | | | |
Collapse
|
5
|
Mellon SH. Neurosteroid regulation of central nervous system development. Pharmacol Ther 2007; 116:107-24. [PMID: 17651807 PMCID: PMC2386997 DOI: 10.1016/j.pharmthera.2007.04.011] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Accepted: 04/25/2007] [Indexed: 12/28/2022]
Abstract
Neurosteroids are a relatively new class of neuroactive compounds brought to prominence in the past 2 decades. Despite knowing of their presence in the nervous system of various species for over 20 years and knowing of their functions as GABA(A) and N-methyl-d-aspartate (NMDA) ligands, new and unexpected functions of these compounds are continuously being identified. Absence or reduced concentrations of neurosteroids during development and in adults may be associated with neurodevelopmental, psychiatric, or behavioral disorders. Treatment with physiologic or pharmacologic concentrations of these compounds may also promote neurogenesis, neuronal survival, myelination, increased memory, and reduced neurotoxicity. This review highlights what is currently known about the neurodevelopmental functions and mechanisms of action of 4 distinct neurosteroids: pregnenolone, progesterone, allopregnanolone, and dehydroepiandrosterone (DHEA).
Collapse
Affiliation(s)
- Synthia H Mellon
- Department of Obstetrics, Gynecology and Reproductive Sciences, Center for Reproductive Sciences, University of California San Francisco, Box 0556, San Francisco, CA 94143-0556, USA.
| |
Collapse
|
6
|
Gago N, El-Etr M, Sananès N, Cadepond F, Samuel D, Avellana-Adalid V, Baron-Van Evercooren A, Schumacher M. 3alpha,5alpha-Tetrahydroprogesterone (allopregnanolone) and gamma-aminobutyric acid: autocrine/paracrine interactions in the control of neonatal PSA-NCAM+ progenitor proliferation. J Neurosci Res 2005; 78:770-83. [PMID: 15523635 DOI: 10.1002/jnr.20348] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The earliest identified neonatal neural progenitors are cells that express the polysialylated form of the neural cell adhesion molecule (PSA-NCAM). One of these progenitors is the early PSA-NCAM+ progenitor (ePSA-NCAM+ progenitor; Gago et al. [2003] Mol Cell Neurosci 22:162-178), which corresponds to a multipotential cell with a default differentiation through glial lineages. The ePSA-NCAM+ progenitor can synthesize the neurosteroid progesterone (PROG) and its reduced metabolite 3alpha,5alpha-tetrahydroprogesterone (3alpha,5alpha-THP, or allopregnanolone; Gago et al. [ 2001] Glia 36:295-308). The latter is a potent positive allosteric modulator of gamma-aminobutyric acid type A (GABAA) receptors. In the present work, we demonstrate that PROG and 3alpha,5alpha-THP both stimulate ePSA-NCAM+ progenitor proliferation. PROG exerted its mitogenic effect indirectly, through its conversion to 3alpha,5alpha-THP, since it could be abolished by an inhibitor of the 5alpha-reductase (L685-273) and mimicked by 3alpha,5alpha-THP. A dose-response curve revealed a bell-shaped effect of 3alpha,5alpha-THP on ePSA-NCAM+ progenitor proliferation, with greatest stimulation at nanomolar concentrations. The mitogenic effect of 3 alpha,5 alpha-THP was mediated by GABAA receptors, insofar as it could be blocked by the selective antagonist bicuculline. ePSA-NCAM+ progenitors indeed expressed mRNAs for GABAA receptor subunits, and GABA enhanced cell proliferation, an effect that was also bicuculline sensitive. Moreover, these cells synthesized GABA, which was involved in a tonic stimulation of their proliferation. These results reveal complex autocrine/paracrine loops in the control of ePSA-NCAM+ progenitor proliferation, involving both neurosteroid and GABA signaling, and suggest a novel key role for 3alpha,5alpha-THP in the development of the nervous system.
Collapse
|
7
|
Rout UK. Alcohol, GABA receptors, and neurodevelopmental disorders. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2005; 71:217-37. [PMID: 16512353 DOI: 10.1016/s0074-7742(05)71010-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Ujjwal K Rout
- Department of Surgery, Division of Pediatric Surgery, Research Laboratories University of Mississippi Medical Center, Jackson 39216, USA
| |
Collapse
|
8
|
Marshall CAG, Suzuki SO, Goldman JE. Gliogenic and neurogenic progenitors of the subventricular zone: who are they, where did they come from, and where are they going? Glia 2003; 43:52-61. [PMID: 12761867 DOI: 10.1002/glia.10213] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The subventricular zone (SVZ) of the perinatal forebrain gives rise to both neurons and glia. The mechanisms governing the phenotypic specification of progenitors within this heterogeneous germinal zone are unclear. However, the characterization of subpopulations of SVZ cells has given us a better understanding of the basic architecture of the SVZ and presents us with the opportunity to ask more detailed questions regarding phenotype specification and cell fate. Recent work demonstrating the embryonic origins of SVZ cells is summarized, and a model describing the formation of the perinatal SVZ, noting contributions of cells from pallial as well as subpallial germinal zones, is presented. We further address differences among classes of SVZ cells based on molecular profile, phenotype, and migration behavior and present a model summarizing the organization of perinatal SVZ cells along coronal, sagittal, and horizontal axes. A detailed description of the SVZ in the adult, outlining classes of cells based on morphology, molecular profile, and proliferative behavior, was recently reported by Doetsch et al. (Proc Natl Acad Sci USA 93:14895-14900, 1997). Potential relationships among cells within the perinatal and adult SVZ will be discussed. GLIA 43:52-61, 2003.
Collapse
Affiliation(s)
- Christine A G Marshall
- Center for Neurobiology and Behavior, Division of Neuropathology, Department of Pathology, Columbia University, College of Physicians and Surgeons, New York, New York
| | - Satoshi O Suzuki
- Center for Neurobiology and Behavior, Division of Neuropathology, Department of Pathology, Columbia University, College of Physicians and Surgeons, New York, New York
| | - James E Goldman
- Center for Neurobiology and Behavior, Division of Neuropathology, Department of Pathology, Columbia University, College of Physicians and Surgeons, New York, New York
| |
Collapse
|
9
|
Autocrine/paracrine activation of the GABA(A) receptor inhibits the proliferation of neurogenic polysialylated neural cell adhesion molecule-positive (PSA-NCAM+) precursor cells from postnatal striatum. J Neurosci 2003. [PMID: 12716935 DOI: 10.1523/jneurosci.23-08-03278.2003] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
GABA and its type A receptor (GABA(A)R) are present in the immature CNS and may function as growth-regulatory signals during the development of embryonic neural precursor cells. In the present study, on the basis of their isopycnic properties in a buoyant density gradient, we developed an isolation procedure that allowed us to purify proliferative neural precursor cells from early postnatal rat striatum, which expressed the polysialylated form of the neural cell adhesion molecule (PSA-NCAM). These postnatal striatal PSA-NCAM+ cells were shown to proliferate in the presence of epidermal growth factor (EGF) and formed spheres that preferentially generated neurons in vitro. We demonstrated that PSA-NCAM+ neuronal precursors from postnatal striatum expressed GABA(A)R subunits in vitro and in situ. GABA elicited chloride currents in PSA-NCAM+ cells by activation of functional GABA(A)R that displayed a typical pharmacological profile. GABA(A)R activation in PSA-NCAM+ cells triggered a complex intracellular signaling combining a tonic inhibition of the mitogen-activated protein kinase cascade and an increase of intracellular calcium concentration by opening of voltage-gated calcium channels. We observed that the activation of GABA(A)R in PSA-NCAM+ neuronal precursors from postnatal striatum inhibited cell cycle progression both in neurospheres and in organotypic slices. Furthermore, postnatal PSA-NCAM+ striatal cells synthesized and released GABA, thus creating an autocrine/paracrine mechanism that controls their proliferation. We showed that EGF modulated this autocrine/paracrine loop by decreasing GABA production in PSA-NCAM+ cells. This demonstration of GABA synthesis and GABA(A)R function in striatal PSA-NCAM+ cells may shed new light on the understanding of key extrinsic cues that regulate the developmental potential of postnatal neuronal precursors in the CNS.
Collapse
|
10
|
Gulinello M, Gong QH, Smith SS. Progesterone withdrawal increases the alpha4 subunit of the GABA(A) receptor in male rats in association with anxiety and altered pharmacology - a comparison with female rats. Neuropharmacology 2002; 43:701-14. [PMID: 12367616 PMCID: PMC2887344 DOI: 10.1016/s0028-3908(02)00171-5] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Withdrawal from the neurosteroid 3alpha,5alpha-allopregnanolone after chronic administration of progesterone increases anxiety in female rats and up-regulates the alpha4 subunit of the GABA(A) receptor (GABA(A)-R) in the hippocampus. We investigated if these phenomena would also occur in male rats. Progesterone withdrawal (PWD) induced higher alpha4 subunit expression in the hippocampus of both male and female rats, in association with increased anxiety (assessed in the elevated plus maze) comparable to effects previously reported. Because alpha4-containing GABA(A)-R are insensitive to the benzodiazepine (BDZ) lorazepam (LZM), and are positively modulated by flumazenil (FLU, a BDZ antagonist), we therefore tested the effects of these compounds following PWD. Using whole-cell patch clamp techniques, LZM-potentiation of GABA ((EC20))-gated current was markedly reduced in CA1 pyramidal cells of male rats undergoing PWD compared to controls, whereas FLU had no effect on GABA-gated current in control animals but increased it in PWD animals. Behaviorally, both male and female rats were significantly less sensitive to the anxiolytic effects of LZM. In contrast, FLU demonstrated significant anxiolytic effects following PWD. These data suggest that neurosteroid regulation of the alpha4 GABA(A)-R subunit may be a relevant mechanism underlying anxiety disorders, and that this phenomenon is not sex-specific.
Collapse
Affiliation(s)
- M. Gulinello
- SUNY Downstate Medical Center, Dept. of Physiology and Pharmacology, 450 Clarkson Avenue, 11203-2098 Brooklyn, NY USA
| | - Q. H. Gong
- SUNY Downstate Medical Center, Dept. of Physiology and Pharmacology, 450 Clarkson Avenue, 11203-2098 Brooklyn, NY USA
| | - S. S. Smith
- SUNY Downstate Medical Center, Dept. of Physiology and Pharmacology, 450 Clarkson Avenue, 11203-2098 Brooklyn, NY USA
| |
Collapse
|
11
|
Gago N, Akwa Y, Sananès N, Guennoun R, Baulieu EE, El-Etr M, Schumacher M. Progesterone and the oligodendroglial lineage: stage-dependent biosynthesis and metabolism. Glia 2001; 36:295-308. [PMID: 11746767 DOI: 10.1002/glia.1117] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Evidence has been accumulated showing that neurosteroids, particularly progesterone (PROG) and its metabolites, may participate in myelination and remyelination in the peripheral nervous system, but very few studies have been undertaken in the central nervous system (CNS). The aim of this work was to investigate the capacities of synthesis and metabolism of PROG at three important stages of the oligodendroglial lineage: oligodendrocyte pre-progenitors (OPP), oligodendrocyte progenitors (OP), and fully differentiated oligodendrocytes (OL). Experiments have been conducted in vitro using highly purified primary cell cultures from rat brain. Cells were incubated with (3)H-pregnenolone ((3)H-PREG), the immediate precursor of PROG, or with (3)H-PROG, and steroids metabolites were then identified by thin layer chromatography and high-performance liquid chromatography (HPLC). mRNA expression of key steroidogenic enzymes was evaluated by reverse transcription-polymerase chain reaction (RT-PCR). The results showed that only OPP and OP, but not OL, expressed 3 beta-hydroxysteroid dehydrogenase/Delta 5-Delta 4 isomerase mRNA and were able to synthesize PROG from PREG. In the three cell types studied, PROG was metabolized by the type 1 isoform of 5 alpha-reductase into 5 alpha-dihydroprogesterone (5 alpha-DHPROG). This enzyme exhibited a 5-fold higher activity in OL than in OPP and OP. 5 alpha-DHPROG was further transformed either into 3 alpha,5 alpha-tetrahydroprogesterone (3 alpha,5 alpha-THPROG), known as a positive allosteric modulator of the GABA(A) receptor, or into the 3 beta-isomer. The 3 alpha,5 alpha-THPROG synthesis was 10 times higher in OPP than in the other cell studied, while the 3 beta,5 alpha-THPROG production did not change with cell differentiation. PROG synthesis and metabolism and the dramatic changes in neurosteroidogenesis observed during the oligodendroglial differentiation may contribute to oligodendrocyte development or the myelination process.
Collapse
Affiliation(s)
- N Gago
- INSERM U 488, Bicêtre, France.
| | | | | | | | | | | | | |
Collapse
|
12
|
Shaffer KM, Lin HJ, Maric D, Pancrazio JJ, Stenger DA, Barker JL, Ma W. The use of GABA(A) receptors expressed in neural precursor cells for cell-based assays. Biosens Bioelectron 2001; 16:481-9. [PMID: 11544042 DOI: 10.1016/s0956-5663(01)00162-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
GABA(A) receptors are known targets for certain classes of environmental neurotoxins and pharmaceutical compounds. Since few neural cell lines express functional GABA(A) receptors, the capacity to rapidly screen for compounds that affect GABA(A) receptor function is presently limited. Previous work has demonstrated that rat neural precursor cells express functional GABA(A) receptors that can be monitored via Ca(2+) imaging. This study examined GABA(A) receptor subunit expression to determine whether GABA(A) receptor function and its interactions with neurotoxins is preserved after passaging. Neural precursor cells isolated from embryonic day 13 rat brain were expanded in serum-free medium containing basic fibroblast growth factor and passaged three times. Reverse transcription-polymerase chain reaction analysis demonstrated early expression of abundant mRNAs encoding various GABA(A) receptor subunits. Ca(2+) imaging showed that the highly proliferating precursor cells in passaged cultures maintained expression of functional GABA(A) receptors. In addition, we showed that trimethylolpropane phosphate, a neurotoxin generated during partial pyrolysis of a synthetic ester turbine engine lubricant, potently inhibited muscimol (GABA(A) receptor agonist) but not depolarization-induced cytosolic Ca(2+) increase. The findings of this study suggest that neural precursor cells may be well suited for the evaluation of certain environmental neurotoxins with convulsant activity. The potential use of neural precursor cells in high-throughput screens for compounds acting on GABA(A) receptors is discussed.
Collapse
Affiliation(s)
- K M Shaffer
- Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, Washington, DC 20375, USA
| | | | | | | | | | | | | |
Collapse
|
13
|
Ma W, Pancrazio JJ, Andreadis JD, Shaffer KM, Stenger DA, Li BS, Zhang L, Barker JL, Maric D. Ethanol blocks cytosolic Ca2+ responses triggered by activation of GABA(A) receptor/Cl- channels in cultured proliferating rat neuroepithelial cells. Neuroscience 2001; 104:913-22. [PMID: 11440820 DOI: 10.1016/s0306-4522(01)00084-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
GABA(A) receptor/Cl- channels and voltage-gated Ca2+ channels are believed to be important sites of ethanol action in the CNS. Acute exposure of ethanol potentiates GABA(A) receptor/Cl- channel activity and inhibits voltage-gated Ca2+ channels in a number of preparations, mostly post-mitotic neurons. The effects of ethanol on these channels in primary cultures of undifferentiated neural precursor cells remain unknown. To address this issue, we examined the effects of ethanol on GABA(A) agonist-activated elevation of cytosolic Ca2+ in an in vitro model of the cortical neuroepithelium derived from rat basic fibroblast growth factor-expanded neural precursor cells. We found a potent inhibition of GABA(A)-activated elevation of cytosolic Ca2+ by ethanol in actively proliferating cells. Since we had recently demonstrated that GABA(A) receptor activation depolarizes these cells and elevates their cytosolic Ca2+, we tested whether the effects of ethanol involved both GABA(A) receptors and voltage-gated Ca2+ channels. Both extracellular K+- and muscimol-induced cytosolic Ca2+ elevations were abolished by nitrendipine, indicating that both depolarizing stimuli triggered Ca2+ influx through L-type voltage-gated Ca2+ channels. Exposure of proliferating cells to different concentrations of ethanol revealed that the drug was more potent in blocking muscimol-induced compared to K+-evoked cytosolic Ca2+ elevations. These results raise the possibility that ethanol blocks GABAergic stimulation of cytosolic Ca2+ levels in proliferating precursors primarily by interacting with GABA(A) receptor/Cl- channels and secondarily with voltage-gated Ca2+ channels.
Collapse
Affiliation(s)
- W Ma
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC 20375, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
14
|
GABA expression dominates neuronal lineage progression in the embryonic rat neocortex and facilitates neurite outgrowth via GABA(A) autoreceptor/Cl- channels. J Neurosci 2001. [PMID: 11264309 DOI: 10.1523/jneurosci.21-07-02343.2001] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
GABA emerges as a trophic signal during rat neocortical development in which it modulates proliferation of neuronal progenitors in the ventricular/subventricular zone (VZ/SVZ) and mediates radial migration of neurons from the VZ/SVZ to the cortical plate/subplate (CP/SP) region. In this study we investigated the role of GABA in the earliest phases of neuronal differentiation in the CP/SP. GABAergic-signaling components emerging during neuronal lineage progression were comprehensively characterized using flow cytometry and immunophenotyping together with physiological indicator dyes. During migration from the VZ/SVZ to the CP/SP, differentiating cortical neurons became predominantly GABAergic, and their dominant GABA(A) receptor subunit expression pattern changed from alpha4beta1gamma1 to alpha3beta3gamma2gamma3 coincident with an increasing potency of GABA on GABA(A) receptor-mediated depolarization. GABA(A) autoreceptor/Cl(-) channel activity in cultured CP/SP neurons dominated their baseline potential and indirectly their cytosolic Ca(2+) (Ca(2+)c) levels via Ca(2+) entry through L-type Ca(2+) channels. Block of this autocrine circuit at the level of GABA synthesis, GABA(A) receptor activation, intracellular Cl(-) ion homeostasis, or L-type Ca(2+) channels attenuated neurite outgrowth in most GABAergic CP/SP neurons. In the absence of autocrine GABAergic signaling, neuritogenesis could be preserved by depolarizing cells and elevating Ca(2+)c. These results reveal a morphogenic role for GABA during embryonic neocortical neuron development that involves GABA(A) autoreceptors and L-type Ca(2+) channels.
Collapse
|
15
|
Maric D, Liu QY, Grant GM, Andreadis JD, Hu Q, Chang YH, Barker JL, Joseph J, Stenger DA, Ma W. Functional ionotropic glutamate receptors emerge during terminal cell division and early neuronal differentiation of rat neuroepithelial cells. J Neurosci Res 2000; 61:652-62. [PMID: 10972962 DOI: 10.1002/1097-4547(20000915)61:6<652::aid-jnr9>3.0.co;2-j] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Ionotropic glutamate receptors mediate fast forms of excitatory synaptic transmission in mature neurons and may play critical roles in neuronal development. However, the developmental stage at which neuronal cells begin to express functional receptors and their roles in lineage progression remain unclear. In the present study, neural precursor cells were isolated from the cortical neuroepithelium of embryonic day 13 rats, and rapidly expanded in serum-free medium in response to basic fibroblast growth factor. RT-PCR revealed the presence of mRNAs encoding AMPA(A), AMPA(C), KA(1), KA(2), NMDA(1), and NMDA(2D) subunits after 3 days in culture. The functional expression of AMPA/kainate and NMDA receptors was investigated using Ca(2+) imaging and whole-cell patch-clamp recording techniques in cells pulse-labeled with bromodeoxyuridine (BrdU) for 1-4 hr. The recorded cells were then double-immunostained for BrdU incorporation and neuron-specific beta-tubulin (TuJ1). The results show that AMPA/kainate and NMDA induced increases in cytosolic Ca(2+) and inward currents only in differentiating neurons. In contrast, proliferating (BrdU(+)TuJ1(-)) cells failed to respond to any ionotropic glutamate receptor agonists. Interestingly, Ca(2+) imaging revealed that a subpopulation of BrdU(+)TuJ1(+) cells also responded to AMPA, indicating the emergence of functional ionotropic AMPA/kainate receptors during terminal cell division and the earliest commitment to neuronal cell lineage. These in vitro results were supported by flow cytometric sorting of AMPA-responsive cells pulse-labeled with BrdU for 1 hr in vivo, which revealed that functional AMPA receptors appear in BrdU(+)TuJ1(+) cells under physiological conditions and may play a role in terminal cell division.
Collapse
MESH Headings
- Animals
- Bromodeoxyuridine/analysis
- Calcium/analysis
- Cell Differentiation/physiology
- Cells, Cultured
- DNA Primers
- Epithelial Cells/chemistry
- Epithelial Cells/cytology
- Epitopes/analysis
- Excitatory Amino Acid Agonists/pharmacology
- Female
- Flow Cytometry
- Gene Expression Regulation, Developmental
- Kainic Acid/pharmacology
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Mitosis/physiology
- N-Methylaspartate/pharmacology
- Neurons/chemistry
- Neurons/cytology
- Patch-Clamp Techniques
- Polymerase Chain Reaction
- Pregnancy
- Rats
- Rats, Sprague-Dawley
- Receptors, AMPA/analysis
- Receptors, AMPA/genetics
- Receptors, Glutamate/analysis
- Receptors, Glutamate/genetics
- Receptors, Kainic Acid/analysis
- Receptors, Kainic Acid/genetics
- Receptors, N-Methyl-D-Aspartate/analysis
- Receptors, N-Methyl-D-Aspartate/genetics
- Stem Cells/chemistry
- Stem Cells/cytology
- Telencephalon/cytology
- Telencephalon/embryology
- Transcription, Genetic/physiology
- alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/pharmacology
Collapse
Affiliation(s)
- D Maric
- Laboratory of Neurophysiology, NINDS, National Institutes of Health, Bethesda, Maryland, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Ma W, Maric D, Li BS, Hu Q, Andreadis JD, Grant GM, Liu QY, Shaffer KM, Chang YH, Zhang L, Pancrazio JJ, Pant HC, Stenger DA, Barker JL. Acetylcholine stimulates cortical precursor cell proliferation in vitro via muscarinic receptor activation and MAP kinase phosphorylation. Eur J Neurosci 2000; 12:1227-40. [PMID: 10762352 DOI: 10.1046/j.1460-9568.2000.00010.x] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Increasing evidence has shown that some neurotransmitters act as growth-regulatory signals during brain development. Here we report a role for the classical neurotransmitter acetylcholine (ACh) to stimulate proliferation of neural stem cells and stem cell-derived progenitor cells during neural cell lineage progression in vitro. Neuroepithelial cells in the ventricular zone of the embryonic rat cortex were found to express the m2 subtype of the muscarinic receptor. Neural precursor cells dissociated from the embryonic rat cortical neuroepithelium were expanded in culture with basic fibroblast growth factor (bFGF). reverse transcriptase-polymerase chain reaction (RT-PCR) revealed the presence of m2, m3 and m4 muscarinic receptor subtype transcripts, while immunocytochemistry demonstrated m2 protein. ACh and carbachol induced an increase in cytosolic Ca2+ and membrane currents in proliferating (BrdU+) cells, both of which were abolished by atropine. Exposure of bFGF-deprived precursor cells to muscarinic agonists not only increased both cell number and DNA synthesis, but also enhanced differentiation of neurons. These effects were blocked by atropine, indicating the involvement of muscarinic ACh receptors. The growth-stimulating effects were also antagonized by a panel of inhibitors of second messengers, including 1,2-bis-(O-aminophenoxy)-ethane-N,N,N', N'-tetraacetic acid (BAPTA-AM) to chelate cytosolic Ca2+, EGTA to complex extracellular Ca2+, pertussis toxin, which uncouples certain G-proteins, the protein kinase C inhibitor H7 and the mitogen-activated protein kinase (MAPK) inhibitor PD98059. Muscarinic agonists activated MAPK, which was significantly inhibited by atropine and the same panel of inhibitors. Thus, muscarinic receptors expressed by neural precursors transduce a growth-regulatory signal during neurogenesis via pathways involving pertussis toxin-sensitive G-proteins, Ca2+ signalling, protein kinase C activation, MAPK phosphorylation and DNA synthesis.
Collapse
Affiliation(s)
- W Ma
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington DC 20375, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Intermediate zone cells express calcium-permeable AMPA receptors and establish close contact with growing axons. J Neurosci 2000. [PMID: 10632599 DOI: 10.1523/jneurosci.20-02-00696.2000] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Recent studies have shown that cells in the intermediate zone (IZ) of the embryonic neocortex originate in the basal telencephalon and migrate tangentially in the cortical wall (;; ). We had previously observed growing cortical axons closely apposed to calbindin-positive, tangentially oriented cells in the IZ (), and it has been shown that neurites in the IZ express a glutamate transporter (). To test if glutamate released by corticofugal growth cones could influence the tangential IZ cells, we characterized the glutamate receptors expressed by IZ cells using patch-clamp techniques, histochemical labeling, and immunostaining on slices of embryonic mice forebrain. We show that tangential IZ cells express inwardly rectifying kainate responses, but not NMDA responses, and accumulate cobalt after AMPA receptor activation. We conclude that IZ cells express calcium-permeable AMPA receptors. This property correlates with our observation that the GluR2 subunit is not expressed in the IZ. AMPA receptors are activated by a millimolar concentration of glutamate. To know whether this high level of glutamate could occur at the surface of IZ cells, we examined contacts made by corticofugal growth cones and calbindin-positive IZ cells using electron microscopy. We show vesicle-containing neurites tightly apposed to calbindin-positive IZ cells over remarkably long length. This suggests that glutamate released by growing corticofugal axons could reach high concentrations close to AMPA receptors of tangential IZ cells and efficiently activate them to control the intracellular calcium in embryonic IZ cells.
Collapse
|
18
|
Yew DT, Chan WY. Early appearance of acetylcholinergic, serotoninergic, and peptidergic neurons and fibers in the developing human central nervous system. Microsc Res Tech 1999; 45:389-400. [PMID: 10402266 DOI: 10.1002/(sici)1097-0029(19990615)45:6<389::aid-jemt6>3.0.co;2-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Animal experiments have already shown that neurotransmitters and neuropeptides are not only important for normal functioning of the adult central nervous system (CNS) but are also crucial to its development. However, information on the spatio-temporal distribution of these endogenous substances in the developing human CNS is still scarce. With the use of immunocytochemical staining and a constant supply of properly fixed human abortuses from southern China, an early appearance of acetylcholinesterase, enkephalin, and substance P immunoreactivities was detected first in the spinal cord (weeks 5 to 7 of gestation), then in the brainstem nuclei (weeks 11 to 12). Their overlapping localizations in many regions of the CNS suggest possible interactions among neurons containing these substances, which are in turn important for the proper establishment of the neuronal circuitry. Immunoreactivity for neuropeptide Y appeared initially in the lateral region of upper segments of the spinal cord at week 12 of gestation, then spread latero-medially and cranio-caudally to the sacral region. In the hippocampus, neuropeptide Y neurons appeared from week 15 onwards. Serotoninergic neurons were found in the dorsal raphe nucleus at week 10 and then decreased in number as the fetus grew older. Somatostatin releasing inhibitory factor, vasopressin, and oxytocin were detected in the hypothalamus from weeks 12 to 14 onwards, and monoamine oxidase, succinic dehydrogenase, parvalbumin, calbindin D28K, and vasoactive intestinal peptide were found in the visual cortex at midgestation. The early appearance and the abundance of the neurotransmitters and neuropeptides in the developing CNS indicate that they may play a key role in neuronal differentiation.
Collapse
Affiliation(s)
- D T Yew
- Department of Anatomy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | | |
Collapse
|
19
|
Ma W, Liu QY, Jung D, Manos P, Pancrazio JJ, Schaffner AE, Barker JL, Stenger DA. Central neuronal synapse formation on micropatterned surfaces. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1998; 111:231-43. [PMID: 9838136 DOI: 10.1016/s0165-3806(98)00142-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Controlling synapse formation is a key to patterning of neurons into functional circuits and networks in vitro. However, the process of synapse formation among neurons grown on artificial surfaces is relatively unstudied. We cultured embryonic hippocampal cells on trimethoxysilylpropyl-diethylenetriamine (DETA) and tridecafluoro-1, 1,2,2-tetrahydrooctyl-1-dimethylchlorosilane (13F), and on patterns composed of DETA lines separated by 13F spaces. For comparison, neurons were concurrently plated on surfaces coated with uniform poly-d-lysine (PDL). Pre- and postsynaptic specializations were identified by immunostaining for synapsin I and microtubule-associated protein-2 (MAP-2). Spontaneous (SPCs) and evoked (EPCs) postsynaptic currents were recorded using dual patch-clamp techniques. We found that DETA promoted synapse formation, whereas evidence for synapse formation on 13F was barely detected. MAP-2+ neuronal soma and rapidly growing dendrites were co-localized with synapsin I puncta faithfully along DETA lines. The expression of synapsin I puncta, and MAP-2+ soma and dendrites correlated well with the appearance of SPCs. Synapsin I, MAP-2 and SPCs emerged together at days 3-4 and increased at day 7, when EPCs appeared. Synaptic signals occurring during 4-7 days in culture were all GABAergic. These results indicate that fully functional synapses are formed on silane surfaces, demonstrating the suitability of patterned silane surfaces for organizing synapse formation in vitro.
Collapse
Affiliation(s)
- W Ma
- Center for Bio/Molecular Science and Engineering, Code 9600, Naval Research Laboratory, 4555 Overlook Ave. S.W., Washington, DC 20375, USA
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Ma W, Liu QY, Maric D, Sathanoori R, Chang YH, Barker JL. Basic FGF-responsive telencephalic precursor cells express functional GABA(A) receptor/Cl-channels in vitro. JOURNAL OF NEUROBIOLOGY 1998; 35:277-86. [PMID: 9622011 DOI: 10.1002/(sici)1097-4695(19980605)35:3<277::aid-neu5>3.0.co;2-w] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have previously described the expression of specific gamma-aminobutyric acid (GABA)A receptor subunits and their transcripts in the cortical neuroepithelium (Ma and Barker, 1995, 1998). However, it is not clear whether neural precursor cells exposed to basic fibroblast growth factor (bFGF) in vitro reproduce the biological properties of neuroepithelial cells in vivo within the embryonic ventricular zone. In the present study, neural precursor cells were isolated from the telencephalic neuroepithelium of embryonic day 13-13.5 rats and exposed to bFGF in serum-free medium. Basic FGF-responsive cells were capable of dividing and differentiating into neurons and astrocytes. The rapidly dividing cells formed multicellular spheres and then a rosette-like formation in which a majority of cells expressed GABA(A) receptor alpha4, beta1, or gamma1 subunit proteins. We found in perforated patch-clamp recordings that GABA depolarized bromodeoxyundine (BrdU)+ precursor cells, and under voltage-clamp induced a bicuculline-sensitive current that reversed at the Cl- equilibrium potential. GABA also increased cytoplasmic Ca2+ in a significant number of BrdU+ cells that was blocked by bicuculline. The bicuculline sensitivity of these pharmacological effects implicates GABA(A) receptor/Cl- channels, since bicuculline is a competitive GABA(A) antagonist at these channels in well-differentiated cells. It is possible that the three GABA(A) receptor subunits (alpha4, beta1, and gamma1) found in precursor cells form the Cl- channels detected electrophysiologically. The functional GABA(A) receptor/Cl- channels and associated regulation of their cytoplasmic Ca2+ levels via bicuculline-sensitive mechanisms may play significant roles in the regulation of neural cell proliferation in this model neuroepithelium.
Collapse
Affiliation(s)
- W Ma
- Biotechnology Research and Applications Division, Science Applications International Corporation, Rockville, Maryland 20850, USA
| | | | | | | | | | | |
Collapse
|