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Teng L, Qin Q, Zhou Z, Zhou F, Cao C, Yang J, Ding J. Glutamate secretion by embryonic stem cells as an autocrine signal to promote proliferation. Sci Rep 2023; 13:19069. [PMID: 37925518 PMCID: PMC10625544 DOI: 10.1038/s41598-023-46477-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 11/01/2023] [Indexed: 11/06/2023] Open
Abstract
Glutamate, the major excitatory neurotransmitter in the central nervous system, has also been found to play a role in embryonic stem (ES) cells. However, the exact mechanism and function of glutamatergic signaling in ES cells remain poorly understood. In this study, we identified a glutamatergic transmission circuit in ES cells that operates through an autocrine mechanism and regulates cell proliferation. We performed biological analyses to identify the key components involved in glutamate biosynthesis, packaging for secretion, reaction, and reuptake in ES cells, including glutaminase, vesicular glutamate transporter, glutamate N-methyl-D-aspartate (NMDA) receptor, and cell membrane excitatory amino-acid transporter (EAAT). We directly quantified the released glutamate signal using microdialysis-high performance liquid chromatography-tandem mass spectrometry (MD-HPLC-MS-MS). Pharmacological inhibition of endogenous glutamate release and the resulting tonic activation of NMDA receptors significantly affected ES cell proliferation, suggesting that ES cells establish a glutamatergic autocrine niche via releasing and responding to the transmitter for their own regulation.
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Affiliation(s)
- Lin Teng
- Department of Cardiology, Yichang Central People's Hospital/The First College of Clinical Medical Sciences, China Three Gorges University, No. 183 Yiling Road, Yichang, 443003, Hubei, China
- Institute of Cardiovascular Disease, China Three Gorges University, Yichang, 443003, Hubei, China
- College of Basic Medical Sciences, Hubei Key Laboratory of Tumor Microencironment and Immunotherapy, China Three Gorges University, Yichang, 443000, Hubei, China
| | - Qin Qin
- Department of Cardiology, Yichang Central People's Hospital/The First College of Clinical Medical Sciences, China Three Gorges University, No. 183 Yiling Road, Yichang, 443003, Hubei, China
- Institute of Cardiovascular Disease, China Three Gorges University, Yichang, 443003, Hubei, China
| | - Ziyi Zhou
- Department of Cardiology, Yichang Central People's Hospital/The First College of Clinical Medical Sciences, China Three Gorges University, No. 183 Yiling Road, Yichang, 443003, Hubei, China
- Institute of Cardiovascular Disease, China Three Gorges University, Yichang, 443003, Hubei, China
| | - Fei Zhou
- Department of Cardiology, Yichang Central People's Hospital/The First College of Clinical Medical Sciences, China Three Gorges University, No. 183 Yiling Road, Yichang, 443003, Hubei, China
- Institute of Cardiovascular Disease, China Three Gorges University, Yichang, 443003, Hubei, China
| | - Chunyu Cao
- College of Basic Medical Sciences, Hubei Key Laboratory of Tumor Microencironment and Immunotherapy, China Three Gorges University, Yichang, 443000, Hubei, China
| | - Jian Yang
- Department of Cardiology, Yichang Central People's Hospital/The First College of Clinical Medical Sciences, China Three Gorges University, No. 183 Yiling Road, Yichang, 443003, Hubei, China
- Institute of Cardiovascular Disease, China Three Gorges University, Yichang, 443003, Hubei, China
| | - Jiawang Ding
- Department of Cardiology, Yichang Central People's Hospital/The First College of Clinical Medical Sciences, China Three Gorges University, No. 183 Yiling Road, Yichang, 443003, Hubei, China.
- Institute of Cardiovascular Disease, China Three Gorges University, Yichang, 443003, Hubei, China.
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Majumdar S. Role of glutamate in the development of visual pathways. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1147769. [PMID: 38983097 PMCID: PMC11182277 DOI: 10.3389/fopht.2023.1147769] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 02/20/2023] [Indexed: 07/11/2024]
Abstract
Glutamate is an important amino acid, metabolite and excitatory neurotransmitter, which is found in its free form in the extracellular spaces of the central nervous system (CNS). More than half of all synapses in CNS release glutamate. It is the main neurotransmitter driving the light responses in the retina. All types of photoreceptors, bipolar, ganglion and one type of glycinergic amacrine cells express specific subtypes of vesicular glutamate transporters and are the main source of endogenous glutamate in retina, besides Müller glia that are responsible for glutamate homeostasis, release and reuptake. Reduced or excessive extracellular glutamate was detected in the synaptic clefts of several naturally occurring or transgenic eye disease models, in which network rewiring and altered functions were observed. These led to the hypothesis that glutamate is one of the extrinsic signals for visual pathway development. This minireview examines experimental evidences supporting, or refuting, the influence of glutamate on prenatal and postnatal retinal development.
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Affiliation(s)
- Sriparna Majumdar
- Department of Psychology, Santa Clara University, Santa Clara, CA, United States
- Computer Science Department, City College of San Francisco, San Francisco, CA, United States
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3
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Liu J, Yin G, Hu K, Huang H, Xu F, Yang Y, Chen F. Parental uveitis causes elevated hair loss in offspring of C57BL/6J mice. Exp Eye Res 2022; 219:109056. [PMID: 35367248 DOI: 10.1016/j.exer.2022.109056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/17/2022] [Accepted: 03/24/2022] [Indexed: 01/10/2023]
Abstract
Our previous study demonstrated that parental uveitis in a susceptible population can cause hair loss and increase the susceptibility to experimental autoimmune uveitis (EAU) in offspring. However, it is unclear whether parental uveitis affects the development of offspring in an EAU-moderate-susceptible population. Herein, moderate-susceptible C57BL/6J mice were immunized with inter-photoreceptor retinoid binding protein (IRBP) 651-670 to develop EAU and were kept together for mating. Gross examination and histopathological changes of the offspring gestated with parental uveitis were observed to evaluate the impact of parental uveitis on the development of the offspring. Differentially expressed genes (DEGs) were screened by RNA sequencing in the affected skin and eyeball of the offspring on postnatal day 27. Adult offspring were injected 75 μg IRBP651-670 to evaluate their susceptibility to EAU. Gross examination in the offspring revealed hair loss on postnatal days 11-31. Histopathological observation showed increased melanin granules and hair follicles of skin in the affected offspring with hair loss. Gene Ontology (GO) analysis in the skin revealed differential expression of genes involved in the mitotic cell cycle, response to endogenous stimulus, hair follicle development, and hair cycle. The DEGs in the skin were predominately associated with the cell cycle and peroxisome proliferator-activated receptor (PPAR) signaling pathway. The GO enrichment analysis in the eyeball showed differential expression of genes involved in the nervous system development, camera-type eye photoreceptor cell differentiation, neuron projection morphogenesis, axon development, and calcium-induced calcium release activity; enriched pathways included the circadian entrainment and glutamatergic synapses. No increased susceptibility to EAU in offspring gestated from parental remitting EAU was observed at a low-dose 75 μg IRBP induction. These results suggested that parental uveitis in a moderate-susceptible population could affect the skin development and DEG profiles of skin and eyeball related to the response to endogenous stimulus, the PPAR signaling pathway, and glutamatergic synapse, which provides the molecular evidence to explain the influence of parental uveitis on offspring development.
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Affiliation(s)
- Jianping Liu
- Department of Pathology, Chongqing Medical University, Chongqing, PR China
| | - Guangnian Yin
- Laboratory Animal Center, Chongqing Medical University, Chongqing, PR China; The Second Affiliated Hospital of Army Military Medical University, Chongqing, PR China
| | - Kaijiao Hu
- Laboratory Animal Center, Chongqing Medical University, Chongqing, PR China; Chongqing Engineering Research Center for Rodent Laboratory Animals, Chongqing, PR China
| | - Hui Huang
- Laboratory Animal Center, Chongqing Medical University, Chongqing, PR China; Chongqing Engineering Research Center for Rodent Laboratory Animals, Chongqing, PR China
| | - Fei Xu
- Laboratory Animal Center, Chongqing Medical University, Chongqing, PR China; Chongqing Engineering Research Center for Rodent Laboratory Animals, Chongqing, PR China
| | - Yaying Yang
- Department of Pathology, Chongqing Medical University, Chongqing, PR China.
| | - Feilan Chen
- Laboratory Animal Center, Chongqing Medical University, Chongqing, PR China; Chongqing Engineering Research Center for Rodent Laboratory Animals, Chongqing, PR China.
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ATRIP protects progenitor cells against DNA damage in vivo. Cell Death Dis 2020; 11:923. [PMID: 33110058 PMCID: PMC7591577 DOI: 10.1038/s41419-020-03090-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 07/29/2020] [Accepted: 07/30/2020] [Indexed: 12/31/2022]
Abstract
The maintenance of genomic stability during the cell cycle of progenitor cells is essential for the faithful transmission of genetic information. Mutations in genes that ensure genome stability lead to human developmental syndromes. Mutations in Ataxia Telangiectasia and Rad3-related (ATR) or in ATR-interacting protein (ATRIP) lead to Seckel syndrome, which is characterized by developmental malformations and short life expectancy. While the roles of ATR in replicative stress response and chromosomal segregation are well established, it is unknown how ATRIP contributes to maintaining genomic stability in progenitor cells in vivo. Here, we generated the first mouse model to investigate ATRIP function. Conditional inactivation of Atrip in progenitor cells of the CNS and eye led to microcephaly, microphthalmia and postnatal lethality. To understand the mechanisms underlying these malformations, we used lens progenitor cells as a model and found that ATRIP loss promotes replicative stress and TP53-dependent cell death. Trp53 inactivation in Atrip-deficient progenitor cells rescued apoptosis, but increased mitotic DNA damage and mitotic defects. Our findings demonstrate an essential role of ATRIP in preventing DNA damage accumulation during unchallenged replication.
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Abo-Ahmed AI, Emam MA. Expression of vesicular glutamate transporter 2 and 3 and glutamate receptor 1 and 2 mRNAs in the retina of adult laughing doves (Streptopelia senegalensis): An in situ hybridization study. Acta Histochem 2020; 122:151597. [PMID: 32778249 DOI: 10.1016/j.acthis.2020.151597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 10/23/2022]
Abstract
The retina possesses few types of neurons so; it is considered an excellent model for understanding the neural mechanisms underlying basic neural information processing in the brain. Glutamate is the major excitatory neurotransmitter in the vertebrate central nervous system and retina. The present study was carried out to characterize the expression pattern of vesicular glutamate transporter 2 (Vglut2) and 3 (Vglut3) and glutamate receptor 1 (GluR1) and 2 (GluR2) mRNAs in the retina of adult laughing dove (Streptopelia senegalensis) by RT-PCR and in situ hybridization histochemistry. The cerebellum of adult laughing dove was used as a positive control in this study. Vglut2 mRNA was highly expressed only in the granular layer of the cerebellum while Vglut3 mRNA was weakly expressed only in the Purkinje cells layer. In the retina, Vglut2 mRNA was highly expressed in the ganglion cell layer and moderately expressed in the inner nuclear layer while Vglut3 mRNA was moderately expressed only in the inner nuclear layer. GluR1 mRNA was intensely expressed in the Purkinje cells layer while GluR2 mRNA signals were highly detectable in both granular and Purkinje cells layers of the cerebellum. In the retina, moderate expression of GluR1 and intense expression of GluR2 was found in both ganglion cell layer and the internal half of inner nuclear layer mostly amacrine cells. These results suggest that some retinal neuronal cells in the adult laughing dove are glutamatergic. Therefore, GluR1 and 2 are suggested as useful markers for glutamatergic retinal neuronal cells in the adult laughing doves.
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Shtaya A, Sadek AR, Zaben M, Seifert G, Pringle A, Steinhäuser C, Gray WP. AMPA receptors and seizures mediate hippocampal radial glia-like stem cell proliferation. Glia 2018; 66:2397-2413. [PMID: 30357924 DOI: 10.1002/glia.23479] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/03/2018] [Accepted: 06/04/2018] [Indexed: 12/25/2022]
Abstract
Neurogenesis is sustained throughout life in the mammalian brain, supporting hippocampus-dependent learning and memory. Its permanent alteration by status epilepticus (SE) is associated with learning and cognitive impairments. The mechanisms underlying the initiation of altered neurogenesis after SE are not understood. Glial fibrillary acidic protein-positive radial glia (RG)-like cells proliferate early after SE, but their proliferation dynamics and signaling are largely unclear. We have previously reported a polarized distribution of AMPA receptors (AMPARs) on RG-like cells in vivo and postulated that these may signal their proliferation. Here, we examined the acute effects of kainate on hippocampal precursor cells in vitro and in kainate-induced SE on proliferating and quiescent clones of 5-bromo-2-deoxyuridine prelabeled hippocampal precursors in vivo. In vitro, we found that 5 μM kainate shortened the cell cycle time of RG-like cells via AMPAR activation and accelerated cell cycle re-entry of their progeny. It also shifted their fate choice expanding the population of RG-like cells and reducing the population of downstream amplifying neural progenitors. Kainate enhanced the survival of all precursor cell subtypes. Pharmacologically, kainate's proliferative and survival effects were abolished by AMPAR blockade. Functional AMPAR expression was confirmed on RG-like cells in vitro. In agreement with these observations, kainate/seizures enhanced the proliferation and expansion predominantly of constitutively cycling RG-like cell clones in vivo. Our results identify AMPARs as key potential players in initiating the proliferation of dentate RG-like cells and unravel a possible receptor target for modifying the radial glia-like cell response to SE.
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Affiliation(s)
- Anan Shtaya
- Neurosciences Research Centre, Molecular and Clinical Sciences Research Institute, St George's, University of London, London, United Kingdom.,University of Southampton School of Medicine, Southampton, United Kingdom
| | | | - Malik Zaben
- University of Southampton School of Medicine, Southampton, United Kingdom.,Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom.,Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, United Kingdom.,B.R.A.I.N. Biomedical Research Unit, Cardiff University, Cardiff, United Kingdom
| | - Gerald Seifert
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Ashley Pringle
- University of Southampton School of Medicine, Southampton, United Kingdom
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - William Peter Gray
- University of Southampton School of Medicine, Southampton, United Kingdom.,Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom.,Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, United Kingdom.,B.R.A.I.N. Biomedical Research Unit, Cardiff University, Cardiff, United Kingdom
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Lahne M, Piekos SM, O'Neill J, Ackerman KM, Hyde DR. Photo-regulation of rod precursor cell proliferation. Exp Eye Res 2018; 178:148-159. [PMID: 30267656 DOI: 10.1016/j.exer.2018.09.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 09/18/2018] [Accepted: 09/26/2018] [Indexed: 11/29/2022]
Abstract
Teleosts are unique in their ability to undergo persistent neurogenesis and to regenerate damaged and lost retinal neurons in adults. This contrasts with the human retina, which is incapable of replacing lost retinal neurons causing vision loss/blindness in the affected individuals. Two cell populations within the adult teleost retina generate new retinal neurons throughout life. Stem cells within the ciliary marginal zone give rise to all retinal cell types except for rod photoreceptors, which are produced by the resident Müller glia that are located within the inner nuclear layer of the entire retina. Understanding the mechanisms that regulate the generation of photoreceptors in the adult teleost retina may ultimately aid developing strategies to overcome vision loss in diseases such as retinitis pigmentosa. Here, we investigated whether photic deprivation alters the proliferative capacity of rod precursor cells, which are generated from Müller glia. In dark-adapted retinas, rod precursor cell proliferation increased, while the number of proliferating Müller glia and their derived olig2:EGFP-positive neuronal progenitor cells was not significantly changed. Cell death of rod photoreceptors was excluded as the inducer of rod precursor cell proliferation, as the number of TUNEL-positive cells and l-plastin-positive microglia in both the outer (ONL) and inner nuclear layer (INL) remained at a similar level throughout the dark-adaptation timecourse. Rod precursor cell proliferation in response to dark-adaptation was characterized by an increased number of EdU-positive cells, i.e. cells that were undergoing DNA replication. These proliferating rod precursor cells in dark-adapted zebrafish differentiated into rod photoreceptors at a comparable percentage and in a similar time frame as those maintained under standard light conditions suggesting that the cell cycle did not stall in dark-adapted retinas. Inhibition of IGF1-receptor signaling reduced the dark-adaptation-mediated proliferation response; however, caloric restriction which has been suggested to be integrated by the IGF1/growth hormone signaling axis did not influence rod precursor cell proliferation in dark-adapted retinas, as similar numbers were observed in starved and normal fed zebrafish. In summary, photic deprivation induces cell cycle entry of rod precursor cells via IGF1-receptor signaling independent of Müller glia proliferation.
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Affiliation(s)
- Manuela Lahne
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Samantha M Piekos
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - John O'Neill
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Kristin M Ackerman
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - David R Hyde
- Department of Biological Sciences, The Center for Stem Cells and Regenerative Medicine and The Center for Zebrafish Research, Galvin Life Sciences Building, University of Notre Dame, Notre Dame, IN, 46556, USA.
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A Promising Antiprion Trimethoxychalcone Binds to the Globular Domain of the Cellular Prion Protein and Changes Its Cellular Location. Antimicrob Agents Chemother 2018; 62:AAC.01441-17. [PMID: 29133563 DOI: 10.1128/aac.01441-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 11/02/2017] [Indexed: 12/28/2022] Open
Abstract
The search for antiprion compounds has been encouraged by the fact that transmissible spongiform encephalopathies (TSEs) share molecular mechanisms with more prevalent neurodegenerative pathologies, such as Parkinson's and Alzheimer's diseases. Cellular prion protein (PrPC) conversion into protease-resistant forms (protease-resistant PrP [PrPRes] or the scrapie form of PrP [PrPSc]) is a critical step in the development of TSEs and is thus one of the main targets in the screening for antiprion compounds. In this work, three trimethoxychalcones (compounds J1, J8, and J20) and one oxadiazole (compound Y17), previously identified in vitro to be potential antiprion compounds, were evaluated through different approaches in order to gain inferences about their mechanisms of action. None of them changed PrPC mRNA levels in N2a cells, as shown by reverse transcription-quantitative real-time PCR. Among them, J8 and Y17 were effective in real-time quaking-induced conversion reactions using rodent recombinant PrP (rPrP) from residues 23 to 231 (rPrP23-231) as the substrate and PrPSc seeds from hamster and human brain. However, when rPrP from residues 90 to 231 (rPrP90-231), which lacks the N-terminal domain, was used as the substrate, only J8 remained effective, indicating that this region is important for Y17 activity, while J8 seems to interact with the PrPC globular domain. J8 also reduced the fibrillation of mouse rPrP23-231 seeded with in vitro-produced fibrils. Furthermore, most of the compounds decreased the amount of PrPC on the N2a cell surface by trapping this protein in the endoplasmic reticulum. On the basis of these results, we hypothesize that J8, a nontoxic compound previously shown to be a promising antiprion agent, may act by different mechanisms, since its efficacy is attributable not only to PrP conversion inhibition but also to a reduction of the PrPC content on the cell surface.
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AMPA glutamate receptors are required for sensory-organ formation and morphogenesis in the basal chordate. Proc Natl Acad Sci U S A 2017; 114:3939-3944. [PMID: 28348228 DOI: 10.1073/pnas.1612943114] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
AMPA-type glutamate receptors (GluAs) mediate fast excitatory transmission in the vertebrate central nervous system (CNS), and their function has been extensively studied in the mature mammalian brain. However, GluA expression begins very early in developing embryos, suggesting that they may also have unidentified developmental roles. Here, we identify developmental roles for GluAs in the ascidian Ciona intestinalis Mammals express Ca2+-permeable GluAs (Ca-P GluAs) and Ca2+-impermeable GluAs (Ca-I GluAs) by combining subunits derived from four genes. In contrast, ascidians have a single gluA gene. Taking advantage of the simple genomic GluA organization in ascidians, we knocked down (KD) GluAs in Ciona and observed severe impairments in formation of the ocellus, a photoreceptive organ used during the swimming stage, and in resorption of the tail and body axis rotation during metamorphosis to the adult stage. These defects could be rescued by injection of KD-resistant GluAs. GluA KD phenotypes could also be reproduced by expressing a GluA mutant that dominantly inhibits glutamate-evoked currents. These results suggest that, in addition to their role in synaptic communication in mature animals, GluAs also have critical developmental functions.
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Glutamate signalling: A multifaceted modulator of oligodendrocyte lineage cells in health and disease. Neuropharmacology 2016; 110:574-585. [PMID: 27346208 DOI: 10.1016/j.neuropharm.2016.06.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 05/27/2016] [Accepted: 06/16/2016] [Indexed: 01/10/2023]
Abstract
Myelin is essential for the mammalian brain to function efficiently. Whilst many factors have been associated with regulating the differentiation of oligodendroglia and myelination, glutamate signalling might be particularly important for learning-dependent myelination. The majority of myelinated projection neurons are glutamatergic. Oligodendrocyte precursor cells receive glutamatergic synaptic inputs from unmyelinated axons and oligodendrocyte lineage cells express glutamate receptors which enable them to monitor and respond to changes in neuronal activity. Yet, what role glutamate plays for oligodendroglia is not fully understood. Here, we review glutamate signalling and its effects on oligodendrocyte lineage cells, and myelination in health and disease. Furthermore, we discuss whether glutamate signalling between neurons and oligodendroglia might lay the foundation to activity-dependent white matter plasticity. This article is part of the Special Issue entitled 'Oligodendrocytes in Health and Disease'.
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Aldiri I, Ajioka I, Xu B, Zhang J, Chen X, Benavente C, Finkelstein D, Johnson D, Akiyama J, Pennacchio LA, Dyer MA. Brg1 coordinates multiple processes during retinogenesis and is a tumor suppressor in retinoblastoma. Development 2016; 142:4092-106. [PMID: 26628093 PMCID: PMC4712833 DOI: 10.1242/dev.124800] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Retinal development requires precise temporal and spatial coordination of cell cycle exit, cell fate specification, cell migration and differentiation. When this process is disrupted, retinoblastoma, a developmental tumor of the retina, can form. Epigenetic modulators are central to precisely coordinating developmental events, and many epigenetic processes have been implicated in cancer. Studying epigenetic mechanisms in development is challenging because they often regulate multiple cellular processes; therefore, elucidating the primary molecular mechanisms involved can be difficult. Here we explore the role of Brg1 (Smarca4) in retinal development and retinoblastoma in mice using molecular and cellular approaches. Brg1 was found to regulate retinal size by controlling cell cycle length, cell cycle exit and cell survival during development. Brg1 was not required for cell fate specification but was required for photoreceptor differentiation and cell adhesion/polarity programs that contribute to proper retinal lamination during development. The combination of defective cell differentiation and lamination led to retinal degeneration in Brg1-deficient retinae. Despite the hypocellularity, premature cell cycle exit, increased cell death and extended cell cycle length, retinal progenitor cells persisted in Brg1-deficient retinae, making them more susceptible to retinoblastoma. ChIP-Seq analysis suggests that Brg1 might regulate gene expression through multiple mechanisms. Summary: The SWI/SNF protein Brg1 controls cell cycle length, cell cycle exit and cell survival, and is required for cell differentiation and retinal lamination, in the developing mouse retina.
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Affiliation(s)
- Issam Aldiri
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Itsuki Ajioka
- Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
| | - Beisi Xu
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jiakun Zhang
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Xiang Chen
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Claudia Benavente
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - David Finkelstein
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Dianna Johnson
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jennifer Akiyama
- Lawrence Berkeley National Laboratory, Genomics Division, Berkeley, CA 94701, USA Department of Energy, Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Len A Pennacchio
- Lawrence Berkeley National Laboratory, Genomics Division, Berkeley, CA 94701, USA Department of Energy, Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Michael A Dyer
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN 38163, USA Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
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Bevilaqua MCDN, Andrade‐da‐Costa BL, Fleming RL, Dias GP, Silveirada Luz ACD, Nardi AE, Mello FG, Gardino PF, Calaza KC. Retinal development impairment and degenerative alterations in adult rats subjected to post‐natal malnutrition. Int J Dev Neurosci 2015; 47:172-82. [DOI: 10.1016/j.ijdevneu.2015.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 09/04/2015] [Accepted: 09/14/2015] [Indexed: 02/04/2023] Open
Affiliation(s)
- Mário Cesar do Nascimento Bevilaqua
- Instituto de Biofísica Carlos Chagas Filho (IBCCF)Universidade Federal do Rio de Janeiro (UFRJ) Brasil, Av. Carlos Chagas Filho, 373, Centro de Ciências da Saúde, Cidade UniversitáriaRio de JaneiroRJCEP 21941‐902Brazil
- Instituto de Psiquiatria, UFRJLaboratório de Pânico e Respiração. Avenida Venceslau Brás ‐ 71–fundos, Praia VermelhaUniversidade Federal do Rio de Janeiro (UFRJ)Rio de JaneiroRJCEP 22290‐140Brazil
| | - Belmira Lara Andrade‐da‐Costa
- Departamento de Fisiologia e Farmacologia, Centro de Ciências BiológicasUniversidade Federal de Pernambuco, Cidade UniversitáriaRecifePECEP 50670‐901Brazil
| | - Renata Lopez Fleming
- Instituto de Biofísica Carlos Chagas Filho (IBCCF)Universidade Federal do Rio de Janeiro (UFRJ) Brasil, Av. Carlos Chagas Filho, 373, Centro de Ciências da Saúde, Cidade UniversitáriaRio de JaneiroRJCEP 21941‐902Brazil
| | - Gisele Pereira Dias
- Instituto de Biofísica Carlos Chagas Filho (IBCCF)Universidade Federal do Rio de Janeiro (UFRJ) Brasil, Av. Carlos Chagas Filho, 373, Centro de Ciências da Saúde, Cidade UniversitáriaRio de JaneiroRJCEP 21941‐902Brazil
- Instituto de Psiquiatria, UFRJLaboratório de Pânico e Respiração. Avenida Venceslau Brás ‐ 71–fundos, Praia VermelhaUniversidade Federal do Rio de Janeiro (UFRJ)Rio de JaneiroRJCEP 22290‐140Brazil
| | - Anna Claudia Domingos Silveirada Luz
- Instituto de Psiquiatria, UFRJLaboratório de Pânico e Respiração. Avenida Venceslau Brás ‐ 71–fundos, Praia VermelhaUniversidade Federal do Rio de Janeiro (UFRJ)Rio de JaneiroRJCEP 22290‐140Brazil
| | - Antonio Egidio Nardi
- Instituto de Psiquiatria, UFRJLaboratório de Pânico e Respiração. Avenida Venceslau Brás ‐ 71–fundos, Praia VermelhaUniversidade Federal do Rio de Janeiro (UFRJ)Rio de JaneiroRJCEP 22290‐140Brazil
| | - Fernando Garcia Mello
- Instituto de Biofísica Carlos Chagas Filho (IBCCF)Universidade Federal do Rio de Janeiro (UFRJ) Brasil, Av. Carlos Chagas Filho, 373, Centro de Ciências da Saúde, Cidade UniversitáriaRio de JaneiroRJCEP 21941‐902Brazil
| | - Patricia Franca Gardino
- Instituto de Biofísica Carlos Chagas Filho (IBCCF)Universidade Federal do Rio de Janeiro (UFRJ) Brasil, Av. Carlos Chagas Filho, 373, Centro de Ciências da Saúde, Cidade UniversitáriaRio de JaneiroRJCEP 21941‐902Brazil
| | - Karin C. Calaza
- Instituto de Biofísica Carlos Chagas Filho (IBCCF)Universidade Federal do Rio de Janeiro (UFRJ) Brasil, Av. Carlos Chagas Filho, 373, Centro de Ciências da Saúde, Cidade UniversitáriaRio de JaneiroRJCEP 21941‐902Brazil
- Departamento de Neurobiologia, Programa de Pós‐graduação em NeurociênciasInstituto de BiologiaUniversidade Federal Fluminense, Brasil – Laboratório de Neurobiologia da Retina. Outeiro de São João Batista, s/n, Campus do Valonguinho, CentroNiteróiRJCEP 24020‐140Brazil
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13
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Abstract
This review compares the biological and physiological function of Sigma receptors [σRs] and their potential therapeutic roles. Sigma receptors are widespread in the central nervous system and across multiple peripheral tissues. σRs consist of sigma receptor one (σ1R) and sigma receptor two (σ2R) and are expressed in numerous regions of the brain. The sigma receptor was originally proposed as a subtype of opioid receptors and was suggested to contribute to the delusions and psychoses induced by benzomorphans such as SKF-10047 and pentazocine. Later studies confirmed that σRs are non-opioid receptors (not an µ opioid receptor) and play a more diverse role in intracellular signaling, apoptosis and metabolic regulation. σ1Rs are intracellular receptors acting as chaperone proteins that modulate Ca2+ signaling through the IP3 receptor. They dynamically translocate inside cells, hence are transmembrane proteins. The σ1R receptor, at the mitochondrial-associated endoplasmic reticulum membrane, is responsible for mitochondrial metabolic regulation and promotes mitochondrial energy depletion and apoptosis. Studies have demonstrated that they play a role as a modulator of ion channels (K+ channels; N-methyl-d-aspartate receptors [NMDAR]; inositol 1,3,5 triphosphate receptors) and regulate lipid transport and metabolism, neuritogenesis, cellular differentiation and myelination in the brain. σ1R modulation of Ca2+ release, modulation of cardiac myocyte contractility and may have links to G-proteins. It has been proposed that σ1Rs are intracellular signal transduction amplifiers. This review of the literature examines the mechanism of action of the σRs, their interaction with neurotransmitters, pharmacology, location and adverse effects mediated through them.
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Affiliation(s)
- Colin G Rousseaux
- a Department of Pathology and Laboratory Medicine , University of Ottawa , Ottawa , ON , Canada and
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14
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Njaine B, Rocha-Martins M, Vieira-Vieira CH, De-Melo LDB, Linden R, Braas K, May V, Martins RAP, Silveira MS. Pleiotropic functions of pituitary adenylyl cyclase-activating polypeptide on retinal ontogenesis: involvement of KLF4 in the control of progenitor cell proliferation. J Mol Neurosci 2014; 54:430-42. [PMID: 24715357 DOI: 10.1007/s12031-014-0299-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 03/27/2014] [Indexed: 12/11/2022]
Abstract
We showed previously that the neuropeptide pituitary adenylyl cyclase-activating polypeptide (PACAP) negatively regulates proliferation of postnatal rat retinal progenitor cells through the downregulation of cyclin D1 in a cAMP/protein kinase A dependent manner. In the present study, we describe by microarray analysis several putative PACAP targets regulated by different transcription factor families. One of these families is the Sp/Klf family of transcriptional factors capable of regulating cyclin D1, and among members, we demonstrate by immunocytochemistry that KLF4 is expressed throughout rat retinal development by retinal progenitor cells and in most differentiated cell types. Using retinal explants preparations, PACAP treatment can transiently increase Klf4 mRNA levels; from electrophoretic mobility shift assays, PACAP is also able to increase the nuclear KLF4 content. From these results, we suggest that KLF4 may be involved in the anti-proliferative effects of PACAP as one mechanism regulating progenitor cell transition from proliferation to differentiation throughout retinal development.
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Affiliation(s)
- Brian Njaine
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Edifício do Centro de Ciencias da Saude, Bloco G, Cidade Universitaria, Ilha do Fundão, 21941-902, Rio de Janeiro, Brazil
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15
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Cavalheiro GR, Matos-Rodrigues GE, Gomes AL, Rodrigues PMG, Martins RAP. c-Myc regulates cell proliferation during lens development. PLoS One 2014; 9:e87182. [PMID: 24503550 PMCID: PMC3913586 DOI: 10.1371/journal.pone.0087182] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 12/20/2013] [Indexed: 12/20/2022] Open
Abstract
Myc protooncogenes play important roles in the regulation of cell proliferation, growth, differentiation and survival during development. In various developing organs, c-myc has been shown to control the expression of cell cycle regulators and its misregulated expression is detected in many human tumors. Here, we show that c-myc gene (Myc) is highly expressed in developing mouse lens. Targeted deletion of c-myc gene from head surface ectoderm dramatically impaired ocular organogenesis, resulting in severe microphtalmia, defective anterior segment development, formation of a lens stalk and/or aphakia. In particular, lenses lacking c-myc presented thinner epithelial cell layer and growth impairment that was detectable soon after its inactivation. Defective development of c-myc-null lens was not caused by increased cell death of lens progenitor cells. Instead, c-myc loss reduced cell proliferation, what was associated with an ectopic expression of Prox1 and p27Kip1 proteins within epithelial cells. Interestingly, a sharp decrease in the expression of the forkhead box transcription factor Foxe3 was also observed following c-myc inactivation. These data represent the first description of the physiological roles played by a Myc family member in mouse lens development. Our findings support the conclusion that c-myc regulates the proliferation of lens epithelial cells in vivo and may, directly or indirectly, modulate the expression of classical cell cycle regulators in developing mouse lens.
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Affiliation(s)
- Gabriel R. Cavalheiro
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gabriel E. Matos-Rodrigues
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Anielle L. Gomes
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo M. G. Rodrigues
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo A. P. Martins
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
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16
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Mariante RM, Nóbrega A, Martins RAP, Areal RB, Bellio M, Linden R. Neuroimmunoendocrine regulation of the prion protein in neutrophils. J Biol Chem 2012; 287:35506-35515. [PMID: 22910907 DOI: 10.1074/jbc.m112.394924] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The prion protein (PrP(C)) is a cell surface protein expressed mainly in the nervous system. In addition to the role of its abnormal conformer in transmissible spongiform encephalopathies, normal PrP(C) may be implicated in other degenerative conditions often associated with inflammation. PrP(C) is also present in cells of hematopoietic origin, including T cells, dendritic cells, and macrophages, and it has been shown to modulate their functions. Here, we investigated the impact of inflammation and stress on the expression and function of PrP(C) in neutrophils, a cell type critically involved in both acute and chronic inflammation. We found that systemic injection of LPS induced transcription and translation of PrP(C) in mouse neutrophils. Up-regulation of PrP(C) was dependent on the serum content of TGF-β and glucocorticoids (GC), which, in turn, are contingent on the activation of the hypothalamic-pituitary-adrenal axis in response to systemic inflammation. GC and TGF-β, either alone or in combination, directly up-regulated PrP(C) in neutrophils, and accordingly, the blockade of GC receptors in vivo curtailed the LPS-induced increase in the content of PrP(C). Moreover, GC also mediated up-regulation of PrP(C) in neutrophils following noninflammatory restraint stress. Finally, neutrophils with up-regulated PrP(C) presented enhanced peroxide-dependent cytotoxicity to endothelial cells. The data demonstrate a novel interplay of the nervous, endocrine, and immune systems upon both the expression and function of PrP(C) in neutrophils, which may have a broad impact upon the physiology and pathology of various organs and systems.
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Affiliation(s)
- Rafael M Mariante
- Institutes of Biophysics, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
| | - Alberto Nóbrega
- Institutes of Microbiology, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Rodrigo A P Martins
- Institutes of Biomedical Sciences, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Rômulo B Areal
- Institutes of Microbiology, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Maria Bellio
- Institutes of Microbiology, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Rafael Linden
- Institutes of Biophysics, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
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17
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Ghosh F, Taylor L, Arnér K. Exogenous Glutamate Modulates Porcine Retinal Development in vitro. Dev Neurosci 2012; 34:428-39. [DOI: 10.1159/000343721] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 09/27/2012] [Indexed: 12/27/2022] Open
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18
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Bedolla DE, Torre V. A component of retinal light adaptation mediated by the thyroid hormone cascade. PLoS One 2011; 6:e26334. [PMID: 22039463 PMCID: PMC3200322 DOI: 10.1371/journal.pone.0026334] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 09/25/2011] [Indexed: 11/18/2022] Open
Abstract
Analysis with DNA-microrrays and real time PCR show that several genes involved in the thyroid hormone cascade, such as deiodinase 2 and 3 (Dio2 and Dio3) are differentially regulated by the circadian clock and by changes of the ambient light. The expression level of Dio2 in adult rats (2-3 months of age) kept continuously in darkness is modulated by the circadian clock and is up-regulated by 2 fold at midday. When the diurnal ambient light was on, the expression level of Dio2 increased by 4-8 fold and a consequent increase of the related protein was detected around the nuclei of retinal photoreceptors and of neurons in inner and outer nuclear layers. The expression level of Dio3 had a different temporal pattern and was down-regulated by diurnal light. Our results suggest that DIO2 and DIO3 have a role not only in the developing retina but also in the adult retina and are powerfully regulated by light. As the thyroid hormone is a ligand-inducible transcription factor controlling the expression of several target genes, the transcriptional activation of Dio2 could be a novel genomic component of light adaptation.
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Affiliation(s)
- Diana E. Bedolla
- Neurobiology Sector, International School for Advanced Studies (SISSA), Trieste, Italy
| | - Vincent Torre
- Neurobiology Sector, International School for Advanced Studies (SISSA), Trieste, Italy
- Italian Institute of Technology (IIT), SISSA-Unit, Trieste, Italy
- * E-mail:
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19
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Njaine B, Martins RAP, Santiago MF, Linden R, Silveira MS. Pituitary adenylyl cyclase-activating polypeptide controls the proliferation of retinal progenitor cells through downregulation of cyclin D1. Eur J Neurosci 2010; 32:311-21. [PMID: 20646049 DOI: 10.1111/j.1460-9568.2010.07286.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
During retinal development, cell proliferation and exit from the cell cycle must be precisely regulated to ensure the generation of the appropriate numbers and proportions of the various retinal cell types. Previously, we showed that pituitary adenylyl cyclase-activating polypeptide (PACAP) exerts a neuroprotective effect in the developing retina of rats, through the cAMP-cAMP-dependent protein kinase (protein kinase A) (PKA) pathway. Here, we show that PACAP also regulates the proliferation of retinal progenitor cells. PACAP, PACAP-specific receptor (PAC1), and the receptors activated by both PACAP and vasoactive intestinal peptide (VIP), VPAC1 and VPAC2, are expressed during embryonic and postnatal development of the rat retina. Treatment of retinal explants with PACAP38 reduced the incorporation of [(3)H]thymidine as well as the number of 5-bromo-2'-deoxyuridine-positive and cyclin D1-positive cells. Pharmacological experiments indicated that PACAP triggers this antiproliferative effect through the activation of both PAC1 and VPACs, and the cAMP-PKA pathway. In addition, PACAP receptor activation decreased both cyclin D1 mRNA and protein content. Altogether, the data support the hypothesis that PACAP is a cell-extrinsic regulator with multiple roles during retinal development, including the regulation of proliferation in a subpopulation of retinal progenitor cells.
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Affiliation(s)
- Brian Njaine
- Instituto de Biofisica Carlos Chagas Filho-UFRJ, Edifício do Centro de Ciencias da Saude, Ilha do Fundão, Rio de Janeiro, Brazil
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20
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Rial D, Takahashi RN, Morato GS. Aniracetam and DNQX affect the acquisition of rapid tolerance to ethanol in mice. Pharmacol Biochem Behav 2008; 92:32-8. [PMID: 18992274 DOI: 10.1016/j.pbb.2008.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 09/17/2008] [Accepted: 10/13/2008] [Indexed: 12/28/2022]
Abstract
Several studies have emphasized the role of learning in the development of rapid tolerance and have shown that glutamate-mediated neurotransmission plays an important role in this phenomenon. Since the AMPA/kainate receptor system is directly involved in plasticity mechanisms, the influence of this receptor system on rapid tolerance induced by ethanol was studied using the rotarod. In the first experiment, mice were pretreated with aniracetam, an agonist of AMPA/kainate receptors, 30 min before ethanol (2.75 g/kg; IP) treatment, and tested on the rotarod. After 24 h, the groups were tested on the rotarod under ethanol treatment. Aniracetam facilitated the acquisition of rapid tolerance to ethanol. In the second experiment, mice received DNQX, a competitive antagonist of the AMPA receptor, 30 min before ethanol treatment (3 g/kg) and submitted to the rotarod. This dose of ethanol produced tolerance per se. Groups were tested under ethanol treatment (1.75 g/kg) after 24 h. DNQX blocked rapid tolerance to ethanol. Using a similar protocol, the third experiment showed that DNQX blocked the aniracetam-induced facilitation of rapid tolerance to ethanol. Our results show that aniracetam facilitates whereas DNQX blocks ethanol tolerance, suggesting that the non-NMDA receptors are involved in this phenomenon.
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Affiliation(s)
- Daniel Rial
- Dept Farmacologia, Universidade Federal de Santa Catarina, 88049-900, Florianópolis, SC, Brazil
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21
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Hoppmann V, Wu JJ, Søviknes AM, Helvik JV, Becker TS. Expression of the eight AMPA receptor subunit genes in the developing central nervous system and sensory organs of zebrafish. Dev Dyn 2008; 237:788-99. [PMID: 18224707 DOI: 10.1002/dvdy.21447] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The AMPA type glutamate receptors mediate the majority of fast synaptic transmission in the vertebrate nervous system. Whereas mammals have four subunit genes, Gria1-4, zebrafish has retained a duplicated set of eight genes named gria1-4a and b. We give here a detailed overview of the expression patterns of all eight zebrafish subunits within the developing central nervous system and sensory organs at 24, 48, and 72 hr after fertilization. Expression domains include distinct neuronal subsets in the developing forebrain, midbrain, hindbrain, and spinal cord, as well as in the ganglion- and inner nuclear layers of the retina. As a general rule, each pair of duplicated gria genes is differentially expressed, indicating subfunctionalization of AMPA receptor subunit expression in the teleost lineage. Our findings suggest that zebrafish can serve as a useful model system to investigate the role of AMPA receptors and their differential expression in the vertebrate nervous system.
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Affiliation(s)
- Verena Hoppmann
- Sars International Centre for Molecular Marine Biology, University Bergen, Thormøhlensgate, Bergen, Norway
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22
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Martins RAP, Zindy F, Donovan S, Zhang J, Pounds S, Wey A, Knoepfler PS, Eisenman RN, Roussel MF, Dyer MA. N-myc coordinates retinal growth with eye size during mouse development. Genes Dev 2008; 22:179-93. [PMID: 18198336 DOI: 10.1101/gad.1608008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Myc family members play crucial roles in regulating cell proliferation, size, differentiation, and survival during development. We found that N-myc is expressed in retinal progenitor cells, where it regulates proliferation in a cell-autonomous manner. In addition, N-myc coordinates the growth of the retina and eye. Specifically, the retinas of N-myc-deficient mice are hypocellular but are precisely proportioned to the size of the eye. N-myc represses the expression of the cyclin-dependent kinase inhibitor p27Kip1 but acts independently of cyclin D1, the major D-type cyclin in the developing mouse retina. Acute inactivation of N-myc leads to increased expression of p27Kip1, and simultaneous inactivation of p27Kip1 and N-myc rescues the hypocellular phenotype in N-myc-deficient retinas. N-myc is not required for retinal cell fate specification, differentiation, or survival. These data represent the first example of a role for a Myc family member in retinal development and the first characterization of a mouse model in which the hypocellular retina is properly proportioned to the other ocular structures. We propose that N-myc lies upstream of the cell cycle machinery in the developing mouse retina and thus coordinates the growth of both the retina and eye through extrinsic cues.
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Affiliation(s)
- Rodrigo A P Martins
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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23
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Trimarchi JM, Stadler MB, Cepko CL. Individual retinal progenitor cells display extensive heterogeneity of gene expression. PLoS One 2008; 3:e1588. [PMID: 18270576 PMCID: PMC2220035 DOI: 10.1371/journal.pone.0001588] [Citation(s) in RCA: 135] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Accepted: 01/15/2008] [Indexed: 12/28/2022] Open
Abstract
The development of complex tissues requires that mitotic progenitor cells integrate information from the environment. The highly varied outcomes of such integration processes undoubtedly depend at least in part upon variations among the gene expression programs of individual progenitor cells. To date, there has not been a comprehensive examination of these differences among progenitor cells of a particular tissue. Here, we used comprehensive gene expression profiling to define these differences among individual progenitor cells of the vertebrate retina. Retinal progenitor cells (RPCs) have been shown by lineage analysis to be multipotent throughout development and to produce distinct types of daughter cells in a temporal, conserved order. A total of 42 single RPCs were profiled on Affymetrix arrays. In situ hybridizations performed on both retinal sections and dissociated retinal cells were used to validate the results of the microarrays. An extensive amount of heterogeneity in gene expression among RPCs, even among cells isolated from the same developmental time point, was observed. While many classes of genes displayed heterogeneity of gene expression, the expression of transcription factors constituted a significant amount of the observed heterogeneity. In contrast to previous findings, individual RPCs were found to express multiple bHLH transcription factors, suggesting alternative models to those previously developed concerning how these factors may be coordinated. Additionally, the expression of cell cycle related transcripts showed differences among those associated with G2 and M, versus G1 and S phase, suggesting different levels of regulation for these genes. These data provide insights into the types of processes and genes that are fundamental to cell fate choices, proliferation decisions, and, for cells of the central nervous system, the underpinnings of the formation of complex circuitry.
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Affiliation(s)
- Jeffrey M. Trimarchi
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Michael B. Stadler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Constance L. Cepko
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
- Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- *E-mail:
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24
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Rousseaux CG. A Review of Glutamate Receptors II: Pathophysiology and Pathology. J Toxicol Pathol 2008. [DOI: 10.1293/tox.21.133] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Colin G. Rousseaux
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa
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25
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Abstract
This protocol details organotypic cultures of developing mouse, monkey and human retinas, which can be maintained for up to 2 weeks. Intact retinas are placed on polycarbonate filters floating on explant culture medium and fed every day with previously prepared retinal conditioned medium. Developing mouse retinas from E12.5 to P12 have been successfully cultured using this protocol as well as retinas from the equivalent stages of human and monkey development. Although this protocol does not require any special equipment, it provides a relatively high throughput. Retinal explant cultures lend themselves to complex pharmacological and genetic manipulations that are currently not feasible in vivo. A detailed procedure for square wave electroporation of retinal explants is also included to provide a high-throughput means to alter gene expression in the developing retina. This protocol for the preparation of retinal conditioned explant medium requires 4 d. Other steps of this protocol can be completed in 2 h.
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Affiliation(s)
- Stacy L Donovan
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
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26
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Martins RAP, Pearson RA. Control of cell proliferation by neurotransmitters in the developing vertebrate retina. Brain Res 2007; 1192:37-60. [PMID: 17597590 DOI: 10.1016/j.brainres.2007.04.076] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 04/04/2007] [Accepted: 04/20/2007] [Indexed: 01/24/2023]
Abstract
In the developing vertebrate retina, precise coordination of retinal progenitor cell proliferation and cell-cycle exit is essential for the formation of a functionally mature retina. Unregulated or disrupted cell proliferation may lead to dysplasia, retinal degeneration or retinoblastoma. Both cell-intrinsic and -extrinsic factors regulate the proliferation of progenitor cells during CNS development. There is now growing evidence that in the developing vertebrate retina, both slow and fast neurotransmitter systems modulate the proliferation of retinal progenitor cells. Classic neurotransmitters, such as GABA (gamma-amino butyric acid), glycine, glutamate, ACh (acetylcholine) and ATP (adenosine triphosphate) are released, via vesicular or non-vesicular mechanisms, into the immature retinal environment. Furthermore, these neurotransmitters signal through functional receptors even before synapses are formed. Recent evidence indicates that the activation of purinergic and muscarinic receptors may regulate the cell-cycle machinery and consequently the expansion of the retinal progenitor pool. Interestingly, GABA and glutamate appear to have opposing roles, inducing retinal progenitor cell-cycle exit. In this review, we present recent findings that begin to elucidate the roles of neurotransmitters as regulators of progenitor cell proliferation at early stages of retinal development. These studies also raise several new questions, including how these neurotransmitters regulate specific cell-cycle pathways and the mechanisms by which retinal progenitor cells integrate the signals from neurotransmitters and other exogenous factors during vertebrate retina development.
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Affiliation(s)
- Rodrigo A P Martins
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, MS323, Memphis, TN 38105, USA.
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