Expression of Ambra1 in mouse brain during physiological and Alzheimer type aging.

PubMed

Sepe, Sara; Nardacci, Roberta; Fanelli, Francesca; Rosso, Pamela; Bernardi, Cinzia; Cecconi, Francesco; Mastroberardino, Pier G; Piacentini, Mauro; Moreno, Sandra

2014-01-01

Autophagy is a major protein degradation pathway, essential for stress-induced and constitutive protein turnover. In nervous tissue, autophagy is constitutively active and crucial to neuronal survival. The efficiency of the autophagic pathway reportedly undergoes age-related decline, and autophagy defects are observed in neurodegenerative diseases. Since Ambra1 plays a fundamental role in regulating the autophagic process in developing nervous tissue, we investigated the expression of this protein in mature mouse brain and during physiological and Alzheimer type aging. The present study accomplished the first complete map of Ambra1 protein distribution in the various brain areas, and highlights differential expression in neuronal/glial cell populations. Differences in Ambra1 content are possibly related to specific neuronal features and properties, particularly concerning susceptibility to neurodegeneration. Furthermore, the analysis of Ambra1 expression in physiological and pathological brain aging supports important, though conflicting, functions of autophagy in neurodegenerative processes. Thus, novel therapeutic approaches, based on autophagy modulation, should also take into account the age-dependent roles of this mechanism in establishing, promoting, or counteracting neurodegeneration. Copyright © 2014 Elsevier Inc. All rights reserved.

Molecular Imaging Provides Novel Insights on Estrogen Receptor Activity in Mouse Brain

PubMed Central

Stell, Alessia; Belcredito, Silvia; Ciana, Paolo; Maggi, Adriana

2009-01-01

Estrogen receptors have long been known to be expressed in several brain areas in addition to those directly involved in the control of reproductive functions. Investigations in humans and in animal models suggest a strong influence of estrogens on limbic and motor functions, yet the complexity and heterogeneity of neural tissue have limited our approaches to the full understanding of estrogen activity in the central nervous system. The aim of this study was to examine the transcriptional activity of estrogen receptors in the brain of male and female mice. Exploiting the ERE-Luc reporter mouse, we set up a novel, bioluminescence-based technique to study brain estrogen receptor transcriptional activity. Here we show, for the first time, that estrogen receptors are similarly active in male and female brains and that the estrous cycle affects estrogen receptor activity in regions of the central nervous system not known to be associated with reproductive functions. Because of its reproducibility and sensitivity, this novel bioluminescence application candidates as an innovative methodology for the study and development of drugs targeting brain estrogen receptors. PMID:19123998

Molecular imaging provides novel insights on estrogen receptor activity in mouse brain.

PubMed

Stell, Alessia; Belcredito, Silvia; Ciana, Paolo; Maggi, Adriana

2008-01-01

Estrogen receptors have long been known to be expressed in several brain areas in addition to those directly involved in the control of reproductive functions. Investigations in humans and in animal models suggest a strong influence of estrogens on limbic and motor functions, yet the complexity and heterogeneity of neural tissue have limited our approaches to the full understanding of estrogen activity in the central nervous system. The aim of this study was to examine the transcriptional activity of estrogen receptors in the brain of male and female mice. Exploiting the ERE-Luc reporter mouse, we set up a novel, bioluminescence-based technique to study brain estrogen receptor transcriptional activity. Here we show, for the first time, that estrogen receptors are similarly active in male and female brains and that the estrous cycle affects estrogen receptor activity in regions of the central nervous system not known to be associated with reproductive functions. Because of its reproducibility and sensitivity, this novel bioluminescence application stands as a candidate as an innovative methodology for the study and development of drugs targeting brain estrogen receptors.

Effects of Space Flight-Associated Stimuli on Development of Murine and Medaka Sensory-Motor Systems

NASA Technical Reports Server (NTRS)

Wolgemuth, Debra J.

1999-01-01

The major goal of these studies was to continue investigations into the influence of altered gravitational fields on the development and function of the vertebrate brain and nervous system. Of major focus during the 18-month finding period of this award was the maintenance of the animals used in the experimental mouse and medaka model paradigms. The experiments focused on characterization of stress-sensitive periods in neural development and immediate or delayed effects on gene expression, physiology and behavior. The hypothesis under investigation was that the environment of space will have biologically significant effects on the development and function of the vertebrate nervous system. We have postulated that these effects will be more significant on certain neural compartments, such as the vestibular-motor system, and that these effects will have greater impact at particular stages of embryonic and post-natal development of the animal. Development of the central nervous system is well known for its vulnerability and sensitivity to environmental stimuli, although the effects of gravitational influences are poorly understood. The long-term goals of this research effort, initiated previously and continued in limited capacity during this interim period, were to provide important new information on the effects of altered environments during these critical periods.

Neuroscience. Stout guards of the central nervous system.

PubMed

Mechoulam, R; Lichtman, A H

2003-10-03

Endocannabinoids have paradoxical effects on the mammalian nervous system: Sometimes they block neuronal excitability and other times they augment it. In their Perspective, Mechoulam and Lichtman discuss new work (Marsicano et al.) showing that activation of the cannabinoid receptor CB1 by the endocannabinoid anandamide protects against excitotoxic damage in a mouse model of kainic acid-induced epilepsy.

The Orphan Nuclear Receptor TLX/NR2E1 in Neural Stem Cells and Diseases.

PubMed

Wang, Tao; Xiong, Jian-Qiong

2016-02-01

The human TLX gene encodes an orphan nuclear receptor predominantly expressed in the central nervous system. Tailess and Tlx, the TLX homologues in Drosophila and mouse, play essential roles in body-pattern formation and neurogenesis during early embryogenesis and perform crucial functions in maintaining stemness and controlling the differentiation of adult neural stem cells in the central nervous system, especially the visual system. Multiple target genes and signaling pathways are regulated by TLX and its homologues in specific tissues during various developmental stages. This review aims to summarize previous studies including many recent updates from different aspects concerning TLX and its homologues in Drosophila and mouse.

Comparison of intravital thinned skull and cranial window approaches to study CNS immunobiology in the mouse cortex

PubMed Central

Dorand, R Dixon; Barkauskas, Deborah S; Evans, Teresa A; Petrosiute, Agne; Huang, Alex Y

2014-01-01

Fluorescent imaging coupled with high-resolution femtosecond pulsed infrared lasers allows for interrogation of cellular interactions deeper in living tissues than ever imagined. Intravital imaging of the central nervous system (CNS) has provided insights into neuronal development, synaptic transmission, and even immune interactions. In this review we will discuss the two most common intravital approaches for studying the cerebral cortex in the live mouse brain for pre-clinical studies, the thinned skull and cranial window techniques, and focus on the advantages and drawbacks of each approach. In addition, we will discuss the use of neuronal physiologic parameters as determinants of successful surgical and imaging preparation. PMID:25568834

Zika virus-induced hyper excitation precedes death of mouse primary neuron.

PubMed

Gaburro, Julie; Bhatti, Asim; Sundaramoorthy, Vinod; Dearnley, Megan; Green, Diane; Nahavandi, Saeid; Paradkar, Prasad N; Duchemin, Jean-Bernard

2018-04-27

Zika virus infection in new born is linked to congenital syndromes, especially microcephaly. Studies have shown that these neuropathies are the result of significant death of neuronal progenitor cells in the central nervous system of the embryo, targeted by the virus. Although cell death via apoptosis is well acknowledged, little is known about possible pathogenic cellular mechanisms triggering cell death in neurons. We used in vitro embryonic mouse primary neuron cultures to study possible upstream cellular mechanisms of cell death. Neuronal networks were grown on microelectrode array and electrical activity was recorded at different times post Zika virus infection. In addition to this method, we used confocal microscopy and Q-PCR techniques to observe morphological and molecular changes after infection. Zika virus infection of mouse primary neurons triggers an early spiking excitation of neuron cultures, followed by dramatic loss of this activity. Using NMDA receptor antagonist, we show that this excitotoxicity mechanism, likely via glutamate, could also contribute to the observed nervous system defects in human embryos and could open new perspective regarding the causes of adult neuropathies. This model of excitotoxicity, in the context of neurotropic virus infection, highlights the significance of neuronal activity recording with microelectrode array and possibility of more than one lethal mechanism after Zika virus infection in the nervous system.

AAV-PHP.B-Mediated Global-Scale Expression in the Mouse Nervous System Enables GBA1 Gene Therapy for Wide Protection from Synucleinopathy.

PubMed

Morabito, Giuseppe; Giannelli, Serena G; Ordazzo, Gabriele; Bido, Simone; Castoldi, Valerio; Indrigo, Marzia; Cabassi, Tommaso; Cattaneo, Stefano; Luoni, Mirko; Cancellieri, Cinzia; Sessa, Alessandro; Bacigaluppi, Marco; Taverna, Stefano; Leocani, Letizia; Lanciego, José L; Broccoli, Vania

2017-12-06

The lack of technology for direct global-scale targeting of the adult mouse nervous system has hindered research on brain processing and dysfunctions. Currently, gene transfer is normally achieved by intraparenchymal viral injections, but these injections target a restricted brain area. Herein, we demonstrated that intravenous delivery of adeno-associated virus (AAV)-PHP.B viral particles permeated and diffused throughout the neural parenchyma, targeting both the central and the peripheral nervous system in a global pattern. We then established multiple procedures of viral transduction to control gene expression or inactivate gene function exclusively in the adult nervous system and assessed the underlying behavioral effects. Building on these results, we established an effective gene therapy strategy to counteract the widespread accumulation of α-synuclein deposits throughout the forebrain in a mouse model of synucleinopathy. Transduction of A53T-SCNA transgenic mice with AAV-PHP.B-GBA1 restored physiological levels of the enzyme, reduced α-synuclein pathology, and produced significant behavioral recovery. Finally, we provided evidence that AAV-PHP.B brain penetration does not lead to evident dysfunctions in blood-brain barrier integrity or permeability. Altogether, the AAV-PHP.B viral platform enables non-invasive, widespread, and long-lasting global neural expression of therapeutic genes, such as GBA1, providing an invaluable approach to treat neurodegenerative diseases with diffuse brain pathology such as synucleinopathies. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

Visualizing the enteric nervous system using genetically engineered double reporter mice: Comparison with immunofluorescence.

PubMed

Jiang, Yanfen; Dong, Hui; Eckmann, Lars; Hanson, Elaine M; Ihn, Katherine C; Mittal, Ravinder K

2017-01-01

The enteric nervous system (ENS) plays a crucial role in the control of gastrointestinal motility, secretion and absorption functions. Immunohistochemistry has been widely used to visualize neurons of the ENS for more than two decades. Genetically engineered mice that report specific proteins can also be used to visualize neurons of the ENS. The goal of our study was to develop a mouse that expresses fluorescent neuronal nitric oxide synthase (nNOS) and choline acetyltransferase (ChAT), the two proteins expressed in 95% of the ENS neurons. We compared ENS neurons visualized in the reporter mouse with the wild type mouse stained using classical immunostaining techniques. Mice hemizygous for ChAT-ChR2-YFP BAC transgene with expression of the mhChR2:YFP fusion protein directed by ChAT promoter/enhancer regions on the BAC transgene were purchased commercially. The Cre/LoxP technique of somatic recombination was used to construct mice with nNOS positive neurons. The two mice were crossbred and tissues were harvested and examined using fluorescent microscopy. Immunostaining was performed in the wild type mice, using antibodies to nNOS, ChAT, Hu and PGP 9.5. Greater than 95% of the ENS neurons were positive for either nNOS or ChAT or both. The nNOS and ChAT neurons and their processes in the ENS were well visualized in all the regions of the GI tract, i.e., esophagus, small intestine and colon. The number of nNOS and ChAT neurons was approximately same in the reporter mouse and immunostaining method in the wild type mouse. The nNOS fluorescence in the reporter mouse was seen in both cytoplasm as well as nucleus but in the immunostained specimens it was seen only in the cytoplasm. We propose that the genetically engineered double reporter mouse for ChAT and nNOS proteins is a powerful tool to study of the effects of various diseases on the ENS without the need for immunostaining.

The In Vivo PDGF Response During Remyelination in Mouse Spinal Cord Following Murine Hepatitis Virus Strain AS9-Induced Transient Demyelination

DTIC Science & Technology

1998-09-14

repopulation. These and other growth factors interacting with cell adhesion molecules andlor matrix molecules would be expected to mediate oligodendrocyte...oligodendrocyte lineage, along with a closely related CCHC zinc finger, is expressed in developing neurons in the mammalian central nervous system. J...repopulate and remyelinate demyelinated lesions. In vitro studies have shown that platelet- derived growth factor (PDGF) induces proliferation

Lack of Tryptophan Hydroxylase-1 in Mice Results in Gait Abnormalities

PubMed Central

Suidan, Georgette L.; Vanderhorst, Veronique; Hampton, Thomas G.; Wong, Siu Ling; Voorhees, Jaymie R.; Wagner, Denisa D.

2013-01-01

The role of peripheral serotonin in nervous system development is poorly understood. Tryptophan hydroxylase-1 (TPH1) is expressed by non-neuronal cells including enterochromaffin cells of the gut, mast cells and the pineal gland and is the rate-limiting enzyme involved in the biosynthesis of peripheral serotonin. Serotonin released into circulation is taken up by platelets via the serotonin transporter and stored in dense granules. It has been previously reported that mouse embryos removed from Tph1-deficient mothers present abnormal nervous system morphology. The goal of this study was to assess whether Tph1-deficiency results in behavioral abnormalities. We did not find any differences between Tph1-deficient and wild-type mice in general motor behavior as tested by rotarod, grip-strength test, open field and beam walk. However, here we report that Tph1 (−/−) mice display altered gait dynamics and deficits in rearing behavior compared to wild-type (WT) suggesting that tryptophan hydroxylase-1 expression has an impact on the nervous system. PMID:23516593

Lack of tryptophan hydroxylase-1 in mice results in gait abnormalities.

PubMed

Suidan, Georgette L; Duerschmied, Daniel; Dillon, Gregory M; Vanderhorst, Veronique; Hampton, Thomas G; Wong, Siu Ling; Voorhees, Jaymie R; Wagner, Denisa D

2013-01-01

The role of peripheral serotonin in nervous system development is poorly understood. Tryptophan hydroxylase-1 (TPH1) is expressed by non-neuronal cells including enterochromaffin cells of the gut, mast cells and the pineal gland and is the rate-limiting enzyme involved in the biosynthesis of peripheral serotonin. Serotonin released into circulation is taken up by platelets via the serotonin transporter and stored in dense granules. It has been previously reported that mouse embryos removed from Tph1-deficient mothers present abnormal nervous system morphology. The goal of this study was to assess whether Tph1-deficiency results in behavioral abnormalities. We did not find any differences between Tph1-deficient and wild-type mice in general motor behavior as tested by rotarod, grip-strength test, open field and beam walk. However, here we report that Tph1 (-/-) mice display altered gait dynamics and deficits in rearing behavior compared to wild-type (WT) suggesting that tryptophan hydroxylase-1 expression has an impact on the nervous system.

Towards Optogenetic Sensory Replacement

PubMed Central

Doroudchi, M. Mehdi; Greenberg, Kenneth P.; Zorzos, Anthony N.; Hauswirth, William W.; Fonstad, Clifton G.; Horsager, Alan; Boyden, Edward S.

2013-01-01

Over the last several years we have developed a rapidly-expanding suite of genetically-encoded reagents (e.g., ChR2, Halo, Arch, Mac, and others) that, when expressed in specific neuron types in the nervous system, enable their activities to be powerfully and precisely activated and silenced in response to light. If the genes that encode for these reagents can be delivered to cells in the body using gene therapy methods, and if the resultant protein payloads operate safely and effectively over therapeutically important periods of time, these molecules could subserve a set of precise prosthetics that use light as the trigger of information entry into the nervous system, e.g. for sensory replacement. Here we discuss the use of ChR2 to make the photoreceptor-deprived retina, as found in diseases such as retinitis pigmentosa, sensitive to light, enabling restoration of functional vision in a mouse model of blindness. We also discuss arrays of light sources that could be useful for delivering patterned sensory information into the nervous system. PMID:22255005

rAAV Gene Therapy in a Canavan's Disease Mouse Model Reveals Immune Impairments and an Extended Pathology Beyond the Central Nervous System.

PubMed

Ahmed, Seemin Seher; Schattgen, Stefan A; Frakes, Ashley E; Sikoglu, Elif M; Su, Qin; Li, Jia; Hampton, Thomas G; Denninger, Andrew R; Kirschner, Daniel A; Kaspar, Brian; Matalon, Reuben; Gao, Guangping

2016-06-01

Aspartoacylase (AspA) gene mutations cause the pediatric lethal neurodegenerative Canavan disease (CD). There is emerging promise of successful gene therapy for CD using recombinant adeno-associated viruses (rAAVs). Here, we report an intracerebroventricularly delivered AspA gene therapy regime using three serotypes of rAAVs at a 20-fold reduced dose than previously described in AspA(-/-) mice, a bona-fide mouse model of CD. Interestingly, central nervous system (CNS)-restricted therapy prolonged survival over systemic therapy in CD mice but failed to sustain motor functions seen in systemically treated mice. Importantly, we reveal through histological and functional examination of untreated CD mice that AspA deficiency in peripheral tissues causes morphological and functional abnormalities in this heretofore CNS-defined disorder. We demonstrate for the first time that AspA deficiency, possibly through excessive N-acetyl aspartic acid accumulation, elicits both a peripheral and CNS immune response in CD mice. Our data establish a role for peripheral tissues in CD pathology and serve to aid the development of more efficacious and sustained gene therapy for this disease.

Identification of a set of genes showing regionally enriched expression in the mouse brain

PubMed Central

D'Souza, Cletus A; Chopra, Vikramjit; Varhol, Richard; Xie, Yuan-Yun; Bohacec, Slavita; Zhao, Yongjun; Lee, Lisa LC; Bilenky, Mikhail; Portales-Casamar, Elodie; He, An; Wasserman, Wyeth W; Goldowitz, Daniel; Marra, Marco A; Holt, Robert A; Simpson, Elizabeth M; Jones, Steven JM

2008-01-01

Background The Pleiades Promoter Project aims to improve gene therapy by designing human mini-promoters (< 4 kb) that drive gene expression in specific brain regions or cell-types of therapeutic interest. Our goal was to first identify genes displaying regionally enriched expression in the mouse brain so that promoters designed from orthologous human genes can then be tested to drive reporter expression in a similar pattern in the mouse brain. Results We have utilized LongSAGE to identify regionally enriched transcripts in the adult mouse brain. As supplemental strategies, we also performed a meta-analysis of published literature and inspected the Allen Brain Atlas in situ hybridization data. From a set of approximately 30,000 mouse genes, 237 were identified as showing specific or enriched expression in 30 target regions of the mouse brain. GO term over-representation among these genes revealed co-involvement in various aspects of central nervous system development and physiology. Conclusion Using a multi-faceted expression validation approach, we have identified mouse genes whose human orthologs are good candidates for design of mini-promoters. These mouse genes represent molecular markers in several discrete brain regions/cell-types, which could potentially provide a mechanistic explanation of unique functions performed by each region. This set of markers may also serve as a resource for further studies of gene regulatory elements influencing brain expression. PMID:18625066

Identification of a set of genes showing regionally enriched expression in the mouse brain.

PubMed

D'Souza, Cletus A; Chopra, Vikramjit; Varhol, Richard; Xie, Yuan-Yun; Bohacec, Slavita; Zhao, Yongjun; Lee, Lisa L C; Bilenky, Mikhail; Portales-Casamar, Elodie; He, An; Wasserman, Wyeth W; Goldowitz, Daniel; Marra, Marco A; Holt, Robert A; Simpson, Elizabeth M; Jones, Steven J M

2008-07-14

The Pleiades Promoter Project aims to improve gene therapy by designing human mini-promoters (< 4 kb) that drive gene expression in specific brain regions or cell-types of therapeutic interest. Our goal was to first identify genes displaying regionally enriched expression in the mouse brain so that promoters designed from orthologous human genes can then be tested to drive reporter expression in a similar pattern in the mouse brain. We have utilized LongSAGE to identify regionally enriched transcripts in the adult mouse brain. As supplemental strategies, we also performed a meta-analysis of published literature and inspected the Allen Brain Atlas in situ hybridization data. From a set of approximately 30,000 mouse genes, 237 were identified as showing specific or enriched expression in 30 target regions of the mouse brain. GO term over-representation among these genes revealed co-involvement in various aspects of central nervous system development and physiology. Using a multi-faceted expression validation approach, we have identified mouse genes whose human orthologs are good candidates for design of mini-promoters. These mouse genes represent molecular markers in several discrete brain regions/cell-types, which could potentially provide a mechanistic explanation of unique functions performed by each region. This set of markers may also serve as a resource for further studies of gene regulatory elements influencing brain expression.

Astrocytes mediate synapse elimination through MEGF10 and MERTK pathways

NASA Astrophysics Data System (ADS)

Chung, Won-Suk; Clarke, Laura E.; Wang, Gordon X.; Stafford, Benjamin K.; Sher, Alexander; Chakraborty, Chandrani; Joung, Julia; Foo, Lynette C.; Thompson, Andrew; Chen, Chinfei; Smith, Stephen J.; Barres, Ben A.

2013-12-01

To achieve its precise neural connectivity, the developing mammalian nervous system undergoes extensive activity-dependent synapse remodelling. Recently, microglial cells have been shown to be responsible for a portion of synaptic pruning, but the remaining mechanisms remain unknown. Here we report a new role for astrocytes in actively engulfing central nervous system synapses. This process helps to mediate synapse elimination, requires the MEGF10 and MERTK phagocytic pathways, and is strongly dependent on neuronal activity. Developing mice deficient in both astrocyte pathways fail to refine their retinogeniculate connections normally and retain excess functional synapses. Finally, we show that in the adult mouse brain, astrocytes continuously engulf both excitatory and inhibitory synapses. These studies reveal a novel role for astrocytes in mediating synapse elimination in the developing and adult brain, identify MEGF10 and MERTK as critical proteins in the synapse remodelling underlying neural circuit refinement, and have important implications for understanding learning and memory as well as neurological disease processes.

Engineering Biomaterial Properties for Central Nervous System Applications

NASA Astrophysics Data System (ADS)

Rivet, Christopher John

Biomaterials offer unique properties that are intrinsic to the chemistry of the material itself or occur as a result of the fabrication process; iron oxide nanoparticles are superparamagnetic, which enables controlled heating in the presence of an alternating magnetic field, and a hydrogel and electrospun fiber hybrid material provides minimally invasive placement of a fibrous, artificial extracellular matrix for tissue regeneration. Utilization of these unique properties towards central nervous system disease and dysfunction requires a thorough definition of the properties in concert with full biological assessment. This enables development of material-specific features to elicit unique cellular responses. Iron oxide nanoparticles are first investigated for material-dependent, cortical neuron cytotoxicity in vitro and subsequently evaluated for alternating magnetic field stimulation induced hyperthermia, emulating the clinical application for enhanced chemotherapy efficacy in glioblastoma treatment. A hydrogel and electrospun fiber hybrid material is first applied to a rat brain to evaluate biomaterial interface astrocyte accumulation as a function of hybrid material composition. The hybrid material is then utilized towards increasing functional engraftment of dopaminergic progenitor neural stem cells in a mouse model of Parkinson's disease. Taken together, these two scenarios display the role of material property characterization in development of biomaterial strategies for central nervous system repair and regeneration.

New Functions of APC/C Ubiquitin Ligase in the Nervous System and Its Role in Alzheimer's Disease.

PubMed

Fuchsberger, Tanja; Lloret, Ana; Viña, Jose

2017-05-14

The E3 ubiquitin ligase Anaphase Promoting Complex/Cyclosome (APC/C) regulates important processes in cells, such as the cell cycle, by targeting a set of substrates for degradation. In the last decade, APC/C has been related to several major functions in the nervous system, including axon guidance, synaptic plasticity, neurogenesis, and neuronal survival. Interestingly, some of the identified APC/C substrates have been related to neurodegenerative diseases. There is an accumulation of some degradation targets of APC/C in Alzheimer's disease (AD) brains, which suggests a dysregulation of the protein complex in the disorder. Moreover, recently evidence has been provided for an inactivation of APC/C in AD. It has been shown that oligomers of the AD-related peptide, Aβ, induce degradation of the APC/C activator subunit cdh1, in vitro in neurons in culture and in vivo in the mouse hippocampus. Furthermore, in the AD mouse model APP/PS1, lower cdh1 levels were observed in pyramidal neurons in CA1 when compared to age-matched wildtype mice. In this review, we provide a complete list of APC/C substrates that are involved in the nervous system and we discuss their functions. We also summarize recent studies that show neurobiological effects in cdh1 knockout mouse models. Finally, we discuss the role of APC/C in the pathophysiology of AD.

Comparative Genomic Analysis of slc39a12/ZIP12: Insight into a Zinc Transporter Required for Vertebrate Nervous System Development

PubMed Central

Chowanadisai, Winyoo

2014-01-01

The zinc transporter ZIP12, which is encoded by the gene slc39a12, has previously been shown to be important for neuronal differentiation in mouse Neuro-2a neuroblastoma cells and primary mouse neurons and necessary for neurulation during Xenopus tropicalis embryogenesis. However, relatively little is known about the biochemical properties, cellular regulation, or the physiological role of this gene. The hypothesis that ZIP12 is a zinc transporter important for nervous system function and development guided a comparative genetics approach to uncover the presence of ZIP12 in various genomes and identify conserved sequences and expression patterns associated with ZIP12. Ortholog detection of slc39a12 was conducted with reciprocal BLAST hits with the amino acid sequence of human ZIP12 in comparison to the human paralog ZIP4 and conserved local synteny between genomes. ZIP12 is present in the genomes of almost all vertebrates examined, from humans and other mammals to most teleost fish. However, ZIP12 appears to be absent from the zebrafish genome. The discrimination of ZIP12 compared to ZIP4 was unsuccessful or inconclusive in other invertebrate chordates and deuterostomes. Splice variation, due to the inclusion or exclusion of a conserved exon, is present in humans, rats, and cows and likely has biological significance. ZIP12 also possesses many putative di-leucine and tyrosine motifs often associated with intracellular trafficking, which may control cellular zinc uptake activity through the localization of ZIP12 within the cell. These findings highlight multiple aspects of ZIP12 at the biochemical, cellular, and physiological levels with likely biological significance. ZIP12 appears to have conserved function as a zinc uptake transporter in vertebrate nervous system development. Consequently, the role of ZIP12 may be an important link to reported congenital malformations in numerous animal models and humans that are caused by zinc deficiency. PMID:25375179

MicroRNA analysis in mouse neuro-2a cells after pseudorabies virus infection.

PubMed

Li, Yongtao; Zheng, Guanmin; Zhang, Yujuan; Yang, Xia; Liu, Hongying; Chang, Hongtao; Wang, Xinwei; Zhao, Jun; Wang, Chuanqing; Chen, Lu

2017-06-01

Pseudorabies virus (PRV), an alpha herpesvirus can enter the mammalian nervous system, causing Aujezsky's disease. Previous studies have reported an alteration of microRNA (miRNA) expression levels during PRV infections. However, knowledge regarding miRNA response in nervous cells to PRV infection is still unknown. To address this issue, small RNA libraries from infected and uninfected mouse neuroblastoma cells were assessed after Illumina deep sequencing. A total of eight viral miRNA were identified, and ten host miRNAs showed significantly different expression upon PRV infection. Among these, five were analyzed by stem-loop RT-qPCR, which confirmed the above data. Interestingly, these viral miRNAs were mainly found in the large latency transcript region of PRV, and predicted to target a variety of genes, forming a complicated regulatory network. Moreover, ten cellular miRNAs were expressed differently upon PRV infection, including nine upregulated and one downregulated miRNAs. Host targets of these miRNAs obtained by bioinformatics analysis belonged to large signaling networks, mainly encompassing calcium signaling pathway, cAMP signaling pathway, MAPK signaling pathway, and other nervous-associated pathways. These findings further highlighted miRNA features in nervous cells after PRV infection and contributed to unveil the underlying mechanisms of neurotropism as well as the neuropathogenesis of PRV.

Cardiomyocyte-released factors stimulate oligodendrocyte precursor cells proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuroda, Mariko; Muramatsu, Rieko; Precursory Research for Embryonic Science and Technology

The heart produces multiple diffusible factors that are involved in a number of physiological processes, but the action of these factors on the central nervous system is not well understood. In this study, we found that one or more factors released by cardiomyocytes promote oligodendrocyte precursor cell (OPC) proliferation in vitro. Mouse OPCs co-cultured with mouse cardiomyocytes showed higher proliferative ability than OPCs cultured alone. In addition, cardiomyocyte-conditioned media was sufficient to promote OPC proliferation. The phosphorylation of phosphatidylinositol (PI) 3-kinase and extracellular signal-regulated kinase (ERK) in OPCs is necessary for the enhancement of OPC proliferation by cardiomyocyte-conditioned media. These datamore » indicate that heart-derived factors have the ability to directly regulate the function of central nervous system (CNS) cells.« less

Conditional depletion of intellectual disability and Parkinsonism candidate gene ATP6AP2 in fly and mouse induces cognitive impairment and neurodegeneration

PubMed Central

Dubos, Aline; Castells-Nobau, Anna; Meziane, Hamid; Oortveld, Merel A.W.; Houbaert, Xander; Iacono, Giovanni; Martin, Christelle; Mittelhaeuser, Christophe; Lalanne, Valérie; Kramer, Jamie M.; Bhukel, Anuradha; Quentin, Christine; Slabbert, Jan; Verstreken, Patrik; Sigrist, Stefan J.; Messaddeq, Nadia; Birling, Marie-Christine; Selloum, Mohammed; Stunnenberg, Henk G.; Humeau, Yann; Schenck, Annette; Herault, Yann

2015-01-01

ATP6AP2, an essential accessory component of the vacuolar H+ ATPase (V-ATPase), has been associated with intellectual disability (ID) and Parkinsonism. ATP6AP2 has been implicated in several signalling pathways; however, little is known regarding its role in the nervous system. To decipher its function in behaviour and cognition, we generated and characterized conditional knockdowns of ATP6AP2 in the nervous system of Drosophila and mouse models. In Drosophila, ATP6AP2 knockdown induced defective phototaxis and vacuolated photoreceptor neurons and pigment cells when depleted in eyes and altered short- and long-term memory when depleted in the mushroom body. In mouse, conditional Atp6ap2 deletion in glutamatergic neurons (Atp6ap2Camk2aCre/0 mice) caused increased spontaneous locomotor activity and altered fear memory. Both Drosophila ATP6AP2 knockdown and Atp6ap2Camk2aCre/0 mice presented with presynaptic transmission defects, and with an abnormal number and morphology of synapses. In addition, Atp6ap2Camk2aCre/0 mice showed autophagy defects that led to axonal and neuronal degeneration in the cortex and hippocampus. Surprisingly, axon myelination was affected in our mutant mice, and axonal transport alterations were observed in Drosophila. In accordance with the identified phenotypes across species, genome-wide transcriptome profiling of Atp6ap2Camk2aCre/0 mouse hippocampi revealed dysregulation of genes involved in myelination, action potential, membrane-bound vesicles and motor behaviour. In summary, ATP6AP2 disruption in mouse and fly leads to cognitive impairment and neurodegeneration, mimicking aspects of the neuropathology associated with ATP6AP2 mutations in humans. Our results identify ATP6AP2 as an essential gene for the nervous system. PMID:26376863

Conditional depletion of intellectual disability and Parkinsonism candidate gene ATP6AP2 in fly and mouse induces cognitive impairment and neurodegeneration.

PubMed

Dubos, Aline; Castells-Nobau, Anna; Meziane, Hamid; Oortveld, Merel A W; Houbaert, Xander; Iacono, Giovanni; Martin, Christelle; Mittelhaeuser, Christophe; Lalanne, Valérie; Kramer, Jamie M; Bhukel, Anuradha; Quentin, Christine; Slabbert, Jan; Verstreken, Patrik; Sigrist, Stefan J; Messaddeq, Nadia; Birling, Marie-Christine; Selloum, Mohammed; Stunnenberg, Henk G; Humeau, Yann; Schenck, Annette; Herault, Yann

2015-12-01

ATP6AP2, an essential accessory component of the vacuolar H+ ATPase (V-ATPase), has been associated with intellectual disability (ID) and Parkinsonism. ATP6AP2 has been implicated in several signalling pathways; however, little is known regarding its role in the nervous system. To decipher its function in behaviour and cognition, we generated and characterized conditional knockdowns of ATP6AP2 in the nervous system of Drosophila and mouse models. In Drosophila, ATP6AP2 knockdown induced defective phototaxis and vacuolated photoreceptor neurons and pigment cells when depleted in eyes and altered short- and long-term memory when depleted in the mushroom body. In mouse, conditional Atp6ap2 deletion in glutamatergic neurons (Atp6ap2(Camk2aCre/0) mice) caused increased spontaneous locomotor activity and altered fear memory. Both Drosophila ATP6AP2 knockdown and Atp6ap2(Camk2aCre/0) mice presented with presynaptic transmission defects, and with an abnormal number and morphology of synapses. In addition, Atp6ap2(Camk2aCre/0) mice showed autophagy defects that led to axonal and neuronal degeneration in the cortex and hippocampus. Surprisingly, axon myelination was affected in our mutant mice, and axonal transport alterations were observed in Drosophila. In accordance with the identified phenotypes across species, genome-wide transcriptome profiling of Atp6ap2(Camk2aCre/0) mouse hippocampi revealed dysregulation of genes involved in myelination, action potential, membrane-bound vesicles and motor behaviour. In summary, ATP6AP2 disruption in mouse and fly leads to cognitive impairment and neurodegeneration, mimicking aspects of the neuropathology associated with ATP6AP2 mutations in humans. Our results identify ATP6AP2 as an essential gene for the nervous system. © The Author 2015. Published by Oxford University Press.

Japanese encephalitis

PubMed Central

Yun, Sang-Im; Lee, Young-Min

2014-01-01

Japanese encephalitis (JE) is an infectious disease of the central nervous system caused by Japanese encephalitis virus (JEV), a zoonotic mosquito-borne flavivirus. JEV is prevalent in much of Asia and the Western Pacific, with over 4 billion people living at risk of infection. In the absence of antiviral intervention, vaccination is the only strategy to develop long-term sustainable protection against JEV infection. Over the past half-century, a mouse brain-derived inactivated vaccine has been used internationally for active immunization. To date, however, JEV is still a clinically important, emerging, and re-emerging human pathogen of global significance. In recent years, production of the mouse brain-derived vaccine has been discontinued, but 3 new cell culture-derived vaccines are available in various parts of the world. Here we review current aspects of JEV biology, summarize the 4 types of JEV vaccine, and discuss the potential of an infectious JEV cDNA technology for future vaccine development. PMID:24161909

Hmx1 is required for the normal development of somatosensory neurons in the geniculate ganglion

PubMed Central

Quina, Lely A.; Tempest, Lynne; Hsu, Yun-Wei A.; Cox, Timothy C.; Turner, Eric E.

2012-01-01

Hmx1 is a variant homeodomain transcription factor expressed in the developing sensory nervous system, retina, and craniofacial mesenchyme. Recently, mutations at the Hmx1 locus have been linked to craniofacial defects in humans, rats, and mice, but its role in nervous system development is largely unknown. Here we show that Hmx1 is expressed in a subset of sensory neurons in the cranial and dorsal root ganglia which does not correspond to any specific sensory modality. Sensory neurons in the dorsal root and trigeminal ganglia of Hmx1dm/dm mouse embryos have no detectable Hmx1 protein, yet they undergo neurogenesis and express sensory subtype markers normally, demonstrating that Hmx1 is not globally required for the specification of sensory neurons from neural crest precursors. Loss of Hmx1 expression has no obvious effect on the early development of the trigeminal (V), superior (IX/X), or dorsal root ganglia neurons in which it is expressed, but results in marked defects in the geniculate (VII) ganglion. Hmx1dm/dm mouse embryos possess only a vestigial posterior auricular nerve, and general somatosensory neurons in the geniculate ganglion are greatly reduced by mid-gestation. Although Hmx1 is expressed in geniculate neurons prior to cell cycle exit, it does not appear to be required for neurogenesis, and the loss of geniculate neurons is likely to be the result of increased cell death. Fate mapping of neural crest-derived tissues indicates that Hmx1-expressing somatosensory neurons at different axial levels may be derived from either the neural crest or the neurogenic placodes. PMID:22586713

Expression of acid-sensing ion channels and selection of reference genes in mouse and naked mole rat.

PubMed

Schuhmacher, Laura-Nadine; Smith, Ewan St John

2016-12-13

Acid-sensing ion channels (ASICs) are a family of ion channels comprised of six subunits encoded by four genes and they are expressed throughout the peripheral and central nervous systems. ASICs have been implicated in a wide range of physiological and pathophysiological processes: pain, breathing, synaptic plasticity and excitotoxicity. Unlike mice and humans, naked mole-rats do not perceive acid as a noxious stimulus, even though their sensory neurons express functional ASICs, likely an adaptation to living in a hypercapnic subterranean environment. Previous studies of ASIC expression in the mammalian nervous system have often not examined all subunits, or have failed to adequately quantify expression between tissues; to date there has been no attempt to determine ASIC expression in the central nervous system of the naked mole-rat. Here we perform a geNorm study to identify reliable housekeeping genes in both mouse and naked mole-rat and then use quantitative real-time PCR to estimate the relative amounts of ASIC transcripts in different tissues of both species. We identify RPL13A (ribosomal protein L13A) and CANX (calnexin), and β-ACTIN and EIF4A (eukaryotic initiation factor 4a) as being the most stably expressed housekeeping genes in mouse and naked mole-rat, respectively. In both species, ASIC3 was most highly expressed in dorsal root ganglia (DRG), and ASIC1a, ASIC2b and ASIC3 were more highly expressed across all brain regions compared to the other subunits. We also show that ASIC4, a proton-insensitive subunit of relatively unknown function, was highly expressed in all mouse tissues apart from DRG and hippocampus, but was by contrast the lowliest expressed ASIC in all naked mole-rat tissues.

Genetically engineered mouse models shed new light on the pathogenesis of neurofibromatosis type I-related neoplasms of the peripheral nervous system.

PubMed

Brossier, Nicole M; Carroll, Steven L

2012-05-01

Neurofibromatosis type 1 (NF1), the most common genetic disorder affecting the human nervous system, is characterized by the development of multiple benign Schwann cell tumors in skin and large peripheral nerves. These neoplasms, which are termed dermal and plexiform neurofibromas respectively, have distinct clinical courses; of particular note, plexiform, but not dermal, neurofibromas often undergo malignant progression to form malignant peripheral nerve sheath tumors (MPNSTs), the most common malignancy occurring in NF1 patients. In recent years, a number of genetically engineered mouse models have been created to investigate the molecular mechanisms driving the pathogenesis of these tumors. These models have been designed to address key questions including: (1) whether NF1 loss in the Schwann cell lineage is essential for tumorigenesis; (2) what cell type(s) in the Schwann cell lineage gives rise to dermal neurofibromas, plexiform neurofibromas and MPNSTs; (3) how the tumor microenvironment contributes to neoplasia; (4) what additional mutations contribute to neurofibroma-MPNST progression; (5) what role different neurofibromin-regulated Ras proteins play in this process and (6) how dysregulated growth factor signaling facilitates PNS tumorigenesis. In this review, we summarize the major findings from each of these models and their limitations as well as how discrepancies between these models may be reconciled. We also discuss how information gleaned from these models can be synthesized to into a comprehensive model of tumor formation in peripheral nervous system and consider several of the major questions that remain unanswered about this process. Copyright © 2011 Elsevier Inc. All rights reserved.

Model of pediatric pituitary hormone deficiency separates the endocrine and neural functions of the LHX3 transcription factor in vivo.

PubMed

Colvin, Stephanie C; Malik, Raleigh E; Showalter, Aaron D; Sloop, Kyle W; Rhodes, Simon J

2011-01-04

The etiology of most pediatric hormone deficiency diseases is poorly understood. Children with combined pituitary hormone deficiency (CPHD) have insufficient levels of multiple anterior pituitary hormones causing short stature, metabolic disease, pubertal failure, and often have associated nervous system symptoms. Mutations in developmental regulatory genes required for the specification of the hormone-secreting cell types of the pituitary gland underlie severe forms of CPHD. To better understand these diseases, we have created a unique mouse model of CPHD with a targeted knockin mutation (Lhx3 W227ter), which is a model for the human LHX3 W224ter disease. The LHX3 gene encodes a LIM-homeodomain transcription factor, which has essential roles in pituitary and nervous system development in mammals. The introduced premature termination codon results in deletion of the carboxyl terminal region of the LHX3 protein, which is critical for pituitary gene activation. Mice that lack all LHX3 function do not survive beyond birth. By contrast, the homozygous Lhx3 W227ter mice survive, but display marked dwarfism, thyroid disease, and female infertility. Importantly, the Lhx3 W227ter mice have no apparent nervous system deficits. The Lhx3 W227ter mouse model provides a unique array of hormone deficits and facilitates experimental approaches that are not feasible with human patients. These experiments demonstrate that the carboxyl terminus of the LHX3 transcription factor is not required for viability. More broadly, this study reveals that the in vivo actions of a transcription factor in different tissues are molecularly separable.

A distal modular enhancer complex acts to control pituitary- and nervous system-specific expression of the LHX3 regulatory gene.

PubMed

Mullen, Rachel D; Park, Soyoung; Rhodes, Simon J

2012-02-01

Lin-11, Isl-1, and Mec-3 (LIM)-homeodomain (HD)-class transcription factors are critical for many aspects of mammalian organogenesis. Of these, LHX3 is essential for pituitary gland and nervous system development. Pediatric patients with mutations in coding regions of the LHX3 gene have complex syndromes, including combined pituitary hormone deficiency and nervous system defects resulting in symptoms such as dwarfism, thyroid insufficiency, infertility, and developmental delay. The pathways underlying early pituitary development are poorly understood, and the mechanisms by which the LHX3 gene is regulated in vivo are not known. Using bioinformatic and transgenic mouse approaches, we show that multiple conserved enhancers downstream of the human LHX3 gene direct expression to the developing pituitary and spinal cord in a pattern consistent with endogenous LHX3 expression. Several transferable cis elements can individually guide nervous system expression. However, a single 180-bp minimal enhancer is sufficient to confer specific expression in the developing pituitary. Within this sequence, tandem binding sites recognized by the islet-1 (ISL1) LIM-HD protein are essential for enhancer activity in the pituitary and spine, and a pituitary homeobox 1 (PITX1) bicoid class HD element is required for spatial patterning in the developing pituitary. This study establishes ISL1 as a novel transcriptional regulator of LHX3 and describes a potential mechanism for regulation by PITX1. Moreover, these studies suggest models for analyses of the transcriptional pathways coordinating the expression of other LIM-HD genes and provide tools for the molecular analysis and genetic counseling of pediatric patients with combined pituitary hormone deficiency.

A Distal Modular Enhancer Complex Acts to Control Pituitary- and Nervous System-Specific Expression of the LHX3 Regulatory Gene

PubMed Central

Mullen, Rachel D.; Park, Soyoung

2012-01-01

Lin-11, Isl-1, and Mec-3 (LIM)-homeodomain (HD)-class transcription factors are critical for many aspects of mammalian organogenesis. Of these, LHX3 is essential for pituitary gland and nervous system development. Pediatric patients with mutations in coding regions of the LHX3 gene have complex syndromes, including combined pituitary hormone deficiency and nervous system defects resulting in symptoms such as dwarfism, thyroid insufficiency, infertility, and developmental delay. The pathways underlying early pituitary development are poorly understood, and the mechanisms by which the LHX3 gene is regulated in vivo are not known. Using bioinformatic and transgenic mouse approaches, we show that multiple conserved enhancers downstream of the human LHX3 gene direct expression to the developing pituitary and spinal cord in a pattern consistent with endogenous LHX3 expression. Several transferable cis elements can individually guide nervous system expression. However, a single 180-bp minimal enhancer is sufficient to confer specific expression in the developing pituitary. Within this sequence, tandem binding sites recognized by the islet-1 (ISL1) LIM-HD protein are essential for enhancer activity in the pituitary and spine, and a pituitary homeobox 1 (PITX1) bicoid class HD element is required for spatial patterning in the developing pituitary. This study establishes ISL1 as a novel transcriptional regulator of LHX3 and describes a potential mechanism for regulation by PITX1. Moreover, these studies suggest models for analyses of the transcriptional pathways coordinating the expression of other LIM-HD genes and provide tools for the molecular analysis and genetic counseling of pediatric patients with combined pituitary hormone deficiency. PMID:22194342

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2010-03-05

... symptoms of those of sympathetic nervous system hyperactivity. Up to 36% of patients worldwide with... efficiency of chemotherapy in animal (mouse) model system. In addition, we can identify possible...

Leptin sustains spontaneous remyelination in the adult central nervous system

PubMed Central

Matoba, Ken; Muramatsu, Rieko; Yamashita, Toshihide

2017-01-01

Demyelination is a common feature of many central nervous system (CNS) diseases and is associated with neurological impairment. Demyelinated axons are spontaneously remyelinated depending on oligodendrocyte development, which mainly involves molecules expressed in the CNS environment. In this study, we found that leptin, a peripheral hormone secreted from adipocytes, promoted the proliferation of oligodendrocyte precursor cells (OPCs). Leptin increased the OPC proliferation via in vitro phosphorylation of extracellular signal regulated kinase (ERK); whereas leptin neutralization inhibited OPC proliferation and remyelination in a mouse model of toxin-induced demyelination. The OPC-specific leptin receptor long isoform (LepRb) deletion in mice inhibited both OPC proliferation and remyelination in the response to demyelination. Intrathecal leptin administration increased OPC proliferation. These results demonstrated a novel molecular mechanism by which leptin sustained OPC proliferation and remyelination in a pathological CNS. PMID:28091609

Meninges-derived cues control axon guidance.

PubMed

Suter, Tracey A C S; DeLoughery, Zachary J; Jaworski, Alexander

2017-10-01

The axons of developing neurons travel long distances along stereotyped pathways under the direction of extracellular cues sensed by the axonal growth cone. Guidance cues are either secreted proteins that diffuse freely or bind the extracellular matrix, or membrane-anchored proteins. Different populations of axons express distinct sets of receptors for guidance cues, which results in differential responses to specific ligands. The full repertoire of axon guidance cues and receptors and the identity of the tissues producing these cues remain to be elucidated. The meninges are connective tissue layers enveloping the vertebrate brain and spinal cord that serve to protect the central nervous system (CNS). The meninges also instruct nervous system development by regulating the generation and migration of neural progenitors, but it has not been determined whether they help guide axons to their targets. Here, we investigate a possible role for the meninges in neuronal wiring. Using mouse neural tissue explants, we show that developing spinal cord meninges produce secreted attractive and repulsive cues that can guide multiple types of axons in vitro. We find that motor and sensory neurons, which project axons across the CNS-peripheral nervous system (PNS) boundary, are attracted by meninges. Conversely, axons of both ipsi- and contralaterally projecting dorsal spinal cord interneurons are repelled by meninges. The responses of these axonal populations to the meninges are consistent with their trajectories relative to meninges in vivo, suggesting that meningeal guidance factors contribute to nervous system wiring and control which axons are able to traverse the CNS-PNS boundary. Copyright © 2017 Elsevier Inc. All rights reserved.

Complementary Gli activity mediates early patterning of the mouse visual system.

PubMed

Furimsky, Marosh; Wallace, Valerie A

2006-03-01

The Sonic hedgehog (Shh) signaling pathway plays a key role in the development of the vertebrate central nervous system, including the eye. This pathway is mediated by the Gli transcription factors (Gli1, Gli2, and Gli3) that differentially activate and repress the expression of specific downstream target genes. In this study, we investigated the roles of the three vertebrate Glis in mediating midline Shh signaling in early ocular development. We examined the ocular phenotypes of Shh and Gli combination mutant mouse embryos and monitored proximodistal and dorsoventral patterning by the expression of specific eye development regulatory genes using in situ hybridization. We show that midline Shh signaling relieves the repressor activity of Gli3 adjacent to the midline and then promotes eye pattern formation through the nonredundant activities of all three Gli proteins. Gli3, in particular, is required to specify the dorsal optic stalk and to define the boundary between the optic stalk and the optic cup.

Establishing Mouse Models for Zika Virus-induced Neurological Disorders Using Intracerebral Injection Strategies: Embryonic, Neonatal, and Adult.

PubMed

Herrlinger, Stephanie A; Shao, Qiang; Ma, Li; Brindley, Melinda; Chen, Jian-Fu

2018-04-26

The Zika virus (ZIKV) is a flavivirus currently endemic in North, Central, and South America. It is now established that the ZIKV can cause microcephaly and additional brain abnormalities. However, the mechanism underlying the pathogenesis of ZIKV in the developing brain remains unclear. Intracerebral surgical methods are frequently used in neuroscience research to address questions about both normal and abnormal brain development and brain function. This protocol utilizes classical surgical techniques and describes methods that allow one to model ZIKV-associated human neurological disease in the mouse nervous system. While direct brain inoculation does not model the normal mode of virus transmission, the method allows investigators to ask targeted questions concerning the consequence after ZIKV infection of the developing brain. This protocol describes embryonic, neonatal, and adult stages of intraventricular inoculation of ZIKV. Once mastered, this method can become a straightforward and reproducible technique that only takes a few hours to perform.

Quantification of HSV-1-mediated expression of the ferritin MRI reporter in the mouse brain

PubMed Central

Iordanova, B; Goins, WF; Clawson, DS; Hitchens, TK; Ahrens, ET

2017-01-01

The development of effective strategies for gene therapy has been hampered by difficulties verifying transgene delivery in vivo and quantifying gene expression non-invasively. Magnetic resonance imaging (MRI) offers high spatial resolution and three-dimensional views, without tissue depth limitations. The iron-storage protein ferritin is a prototype MRI gene reporter. Ferritin forms a paramagnetic ferrihydrite core that can be detected by MRI via its effect on the local magnetic field experienced by water protons. In an effort to better characterize the ferritin reporter for central nervous system applications, we expressed ferritin in the mouse brain in vivo using a neurotropic herpes simplex virus type 1 (HSV-1). We computed three-dimensional maps of MRI transverse relaxation rates in the mouse brain with ascending doses of ferritin-expressing HSV-1. We established that the transverse relaxation rates correlate significantly to the number of inoculated infectious particles. Our results are potentially useful for quantitatively assessing limitations of ferritin reporters for gene therapy applications. PMID:22996196

Autonomic nervous system involvement in the giant axonal neuropathy (GAN) KO mouse: implications for human disease.

PubMed

Armao, Diane; Bailey, Rachel M; Bouldin, Thomas W; Kim, Yongbaek; Gray, Steven J

2016-08-01

Giant axonal neuropathy (GAN) is an inherited severe sensorimotor neuropathy. The aim of this research was to investigate the neuropathologic features and clinical autonomic nervous system (ANS) phenotype in two GAN knockout (KO) mouse models. Little is known about ANS involvement in GAN in humans, but autonomic signs and symptoms are commonly reported in early childhood. Routine histology and immunohistochemistry was performed on GAN KO mouse specimens taken at various ages. Enteric dysfunction was assessed by quantifying the frequency, weight, and water content of defecation in GAN KO mice. Histological examination of the enteric, parasympathetic and sympathetic ANS of GAN KO mice revealed pronounced and widespread neuronal perikaryal intermediate filament inclusions. These neuronal inclusions served as an easily identifiable, early marker of GAN in young GAN KO mice. Functional studies identified an age-dependent alteration in fecal weight and defecation frequency in GAN KO mice. For the first time in the GAN KO mouse model, we described the early, pronounced and widespread neuropathologic features involving the ANS. In addition, we provided evidence for a clinical autonomic phenotype in GAN KO mice, reflected in abnormal gastrointestinal function. These findings in GAN KO mice suggest that consideration should be given to ANS involvement in human GAN, especially when considering treatments and patient care.

Infectious Progression of Canine Distemper Virus from Circulating Cerebrospinal Fluid into the Central Nervous System.

PubMed

Takenaka, Akiko; Sato, Hiroki; Ikeda, Fusako; Yoneda, Misako; Kai, Chieko

2016-10-15

In the current study, we generated recombinant chimeric canine distemper viruses (CDVs) by replacing the hemagglutinin (H) and/or phosphoprotein (P) gene in an avirulent strain expressing enhanced green fluorescent protein (EGFP) with those of a mouse-adapted neurovirulent strain. An in vitro experimental infection indicated that the chimeric CDVs possessing the H gene derived from the mouse-adapted CDV acquired infectivity for neural cells. These cells lack the CDV receptors that have been identified to date (SLAM and nectin-4), indicating that the H protein defines infectivity in various cell lines. The recombinant viruses were administered intracerebrally to 1-week-old mice. Fatal neurological signs of disease were observed only with a recombinant CDV that possessed both the H and P genes of the mouse-adapted strain, similar to the parental mouse-adapted strain, suggesting that both genes are important to drive virulence of CDV in mice. Using this recombinant CDV, we traced the intracerebral propagation of CDV by detecting EGFP. Widespread infection was observed in the cerebral hemispheres and brainstems of the infected mice. In addition, EGFP fluorescence in the brain slices demonstrated a sequential infectious progression in the central nervous system: CDV primarily infected the neuroependymal cells lining the ventricular wall and the neurons of the hippocampus and cortex adjacent to the ventricle, and it then progressed to an extensive infection of the brain surface, followed by the parenchyma and cortex. In the hippocampal formation, CDV spread in a unidirectional retrograde pattern along neuronal processes in the hippocampal formation from the CA1 region to the CA3 region and the dentate gyrus. Our mouse model demonstrated that the main target cells of CDV are neurons in the acute phase and that the virus spreads via neuronal transmission pathways in the hippocampal formation. CDV is the etiological agent of distemper in dogs and other carnivores, and in many respects, the pathogenesis of CDV infection in animals resembles that of measles virus infection in humans. We successfully generated a recombinant CDV containing the H and P genes from a mouse-adapted neurovirulent strain and expressing EGFP. The recombinant CDV exhibited severe neurovirulence with high mortality, comparable to the parental mouse-adapted strain. The mouse-infectious model could become a useful tool for analyzing CDV infection of the central nervous system subsequent to passing through the blood-cerebrospinal fluid barrier and infectious progression in the target cells in acute disease. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Infectious Progression of Canine Distemper Virus from Circulating Cerebrospinal Fluid into the Central Nervous System

PubMed Central

Takenaka, Akiko; Sato, Hiroki; Ikeda, Fusako; Yoneda, Misako

2016-01-01

ABSTRACT In the current study, we generated recombinant chimeric canine distemper viruses (CDVs) by replacing the hemagglutinin (H) and/or phosphoprotein (P) gene in an avirulent strain expressing enhanced green fluorescent protein (EGFP) with those of a mouse-adapted neurovirulent strain. An in vitro experimental infection indicated that the chimeric CDVs possessing the H gene derived from the mouse-adapted CDV acquired infectivity for neural cells. These cells lack the CDV receptors that have been identified to date (SLAM and nectin-4), indicating that the H protein defines infectivity in various cell lines. The recombinant viruses were administered intracerebrally to 1-week-old mice. Fatal neurological signs of disease were observed only with a recombinant CDV that possessed both the H and P genes of the mouse-adapted strain, similar to the parental mouse-adapted strain, suggesting that both genes are important to drive virulence of CDV in mice. Using this recombinant CDV, we traced the intracerebral propagation of CDV by detecting EGFP. Widespread infection was observed in the cerebral hemispheres and brainstems of the infected mice. In addition, EGFP fluorescence in the brain slices demonstrated a sequential infectious progression in the central nervous system: CDV primarily infected the neuroependymal cells lining the ventricular wall and the neurons of the hippocampus and cortex adjacent to the ventricle, and it then progressed to an extensive infection of the brain surface, followed by the parenchyma and cortex. In the hippocampal formation, CDV spread in a unidirectional retrograde pattern along neuronal processes in the hippocampal formation from the CA1 region to the CA3 region and the dentate gyrus. Our mouse model demonstrated that the main target cells of CDV are neurons in the acute phase and that the virus spreads via neuronal transmission pathways in the hippocampal formation. IMPORTANCE CDV is the etiological agent of distemper in dogs and other carnivores, and in many respects, the pathogenesis of CDV infection in animals resembles that of measles virus infection in humans. We successfully generated a recombinant CDV containing the H and P genes from a mouse-adapted neurovirulent strain and expressing EGFP. The recombinant CDV exhibited severe neurovirulence with high mortality, comparable to the parental mouse-adapted strain. The mouse-infectious model could become a useful tool for analyzing CDV infection of the central nervous system subsequent to passing through the blood-cerebrospinal fluid barrier and infectious progression in the target cells in acute disease. PMID:27489268

Schwann cells use TAM receptor-mediated phagocytosis in addition to autophagy to clear myelin in a mouse model of nerve injury.

PubMed

Brosius Lutz, Amanda; Chung, Won-Suk; Sloan, Steven A; Carson, Glenn A; Zhou, Lu; Lovelett, Emilie; Posada, Sean; Zuchero, J Bradley; Barres, Ben A

2017-09-19

Ineffective myelin debris clearance is a major factor contributing to the poor regenerative ability of the central nervous system. In stark contrast, rapid clearance of myelin debris from the injured peripheral nervous system (PNS) is one of the keys to this system's remarkable regenerative capacity, but the molecular mechanisms driving PNS myelin clearance are incompletely understood. We set out to discover new pathways of PNS myelin clearance to identify novel strategies for activating myelin clearance in the injured central nervous system, where myelin debris is not cleared efficiently. Here we show that Schwann cells, the myelinating glia of the PNS, collaborate with hematogenous macrophages to clear myelin debris using TAM (Tyro3, Axl, Mer) receptor-mediated phagocytosis as well as autophagy. In a mouse model of PNS nerve crush injury, Schwann cells up-regulate TAM phagocytic receptors Axl and Mertk following PNS injury, and Schwann cells lacking both of these phagocytic receptors exhibit significantly impaired myelin phagocytosis both in vitro and in vivo. Autophagy-deficient Schwann cells also display reductions in myelin clearance after mouse nerve crush injury, as has been recently shown following nerve transection. These findings add a mechanism, Axl/Mertk-mediated myelin clearance, to the repertoire of cellular machinery used to clear myelin in the injured PNS. Given recent evidence that astrocytes express Axl and Mertk and have previously unrecognized phagocytic potential, this pathway may be a promising avenue for activating myelin clearance after CNS injury.

Expression and imprinting of MAGEL2 suggest a role in Prader-willi syndrome and the homologous murine imprinting phenotype.

PubMed

Lee, S; Kozlov, S; Hernandez, L; Chamberlain, S J; Brannan, C I; Stewart, C L; Wevrick, R

2000-07-22

Prader-Willi syndrome (PWS) is caused by the loss of expression of imprinted genes in chromosome 15q11-q13. Affected individuals exhibit neonatal hypotonia, developmental delay and childhood-onset obesity. Necdin, a protein implicated in the terminal differentiation of neurons, is the only PWS candidate gene to reduce viability when disrupted in a mouse model. In this study, we have characterized MAGEL2 (also known as NDNL1), a gene with 51% amino acid sequence similarity to necdin and located 41 kb distal to NDN in the PWS deletion region. MAGEL2 is expressed predominantly in brain, the primary tissue affected in PWS and in several fetal tissues as shown by northern blot analysis. MAGEL2 is imprinted with monoallelic expression in control brain, and paternal-only expression in the central nervous system as demonstrated by its lack of expression in brain from a PWS-affected individual. The orthologous mouse gene (Magel2) is located within 150 kb of NDN:, is imprinted with paternal-only expression and is expressed predominantly in late developmental stages and adult brain as shown by northern blotting, RT-PCR and whole-mount RNA in situ hybridization. Magel2 distribution partially overlaps that of NDN:, with strong expression being detected in the central nervous system in mid-gestation mouse embryos by in situ hybridization. We hypothesize that, although loss of necdin expression may be important in the neonatal presentation of PWS, loss of MAGEL2 may be critical to abnormalities in brain development and dysmorphic features in individuals with PWS.

The zinc finger transcription factor Gfi1, implicated in lymphomagenesis, is required for inner ear hair cell differentiation and survival

NASA Technical Reports Server (NTRS)

Wallis, Deeann; Hamblen, Melanie; Zhou, Yi; Venken, Koen J T.; Schumacher, Armin; Grimes, H. Leighton; Zoghbi, Huda Y.; Orkin, Stuart H.; Bellen, Hugo J.

2003-01-01

Gfi1 was first identified as causing interleukin 2-independent growth in T cells and lymphomagenesis in mice. Much work has shown that Gfi1 and Gfi1b, a second mouse homolog, play pivotal roles in blood cell lineage differentiation. However, neither Gfi1 nor Gfi1b has been implicated in nervous system development, even though their invertebrate homologues, senseless in Drosophila and pag-3 in C. elegans are expressed and required in the nervous system. We show that Gfi1 mRNA is expressed in many areas that give rise to neuronal cells during embryonic development in mouse, and that Gfi1 protein has a more restricted expression pattern. By E12.5 Gfi1 mRNA is expressed in both the CNS and PNS as well as in many sensory epithelia including the developing inner ear epithelia. At later developmental stages, Gfi1 expression in the ear is refined to the hair cells and neurons throughout the inner ear. Gfi1 protein is expressed in a more restricted pattern in specialized sensory cells of the PNS, including the eye, presumptive Merkel cells, the lung and hair cells of the inner ear. Gfi1 mutant mice display behavioral defects that are consistent with inner ear anomalies, as they are ataxic, circle, display head tilting behavior and do not respond to noise. They have a unique inner ear phenotype in that the vestibular and cochlear hair cells are differentially affected. Although Gfi1-deficient mice initially specify inner ear hair cells, these hair cells are disorganized in both the vestibule and cochlea. The outer hair cells of the cochlea are improperly innervated and express neuronal markers that are not normally expressed in these cells. Furthermore, Gfi1 mutant mice lose all cochlear hair cells just prior to and soon after birth through apoptosis. Finally, by five months of age there is also a dramatic reduction in the number of cochlear neurons. Hence, Gfi1 is expressed in the developing nervous system, is required for inner ear hair cell differentiation, and its loss causes programmed cell death.

Altered development of the brain after focal herpesvirus infection of the central nervous system.

PubMed

Koontz, Thad; Bralic, Marina; Tomac, Jelena; Pernjak-Pugel, Ester; Bantug, Glen; Jonjic, Stipan; Britt, William J

2008-02-18

Human cytomegalovirus infection of the developing central nervous system (CNS) is a major cause of neurological damage in newborn infants and children. To investigate the pathogenesis of this human infection, we developed a mouse model of infection in the developing CNS. Intraperitoneal inoculation of newborn animals with murine cytomegalovirus resulted in virus replication in the liver followed by virus spread to the brain. Virus infection of the CNS was associated with the induction of inflammatory responses, including the induction of a large number of interferon-stimulated genes and histological evidence of focal encephalitis with recruitment of mononuclear cells to foci containing virus-infected cells. The morphogenesis of the cerebellum was delayed in infected animals. The defects in cerebellar development in infected animals were generalized and, although correlated temporally with virus replication and CNS inflammation, spatially unrelated to foci of virus-infected cells. Specific defects included decreased granular neuron proliferation and migration, expression of differentiation markers, and activation of neurotrophin receptors. These findings suggested that in the developing CNS, focal virus infection and induction of inflammatory responses in resident and infiltrating mononuclear cells resulted in delayed cerebellar morphogenesis.

Altered development of the brain after focal herpesvirus infection of the central nervous system

PubMed Central

Koontz, Thad; Bralic, Marina; Tomac, Jelena; Pernjak-Pugel, Ester; Bantug, Glen; Jonjic, Stipan; Britt, William J.

2008-01-01

Human cytomegalovirus infection of the developing central nervous system (CNS) is a major cause of neurological damage in newborn infants and children. To investigate the pathogenesis of this human infection, we developed a mouse model of infection in the developing CNS. Intraperitoneal inoculation of newborn animals with murine cytomegalovirus resulted in virus replication in the liver followed by virus spread to the brain. Virus infection of the CNS was associated with the induction of inflammatory responses, including the induction of a large number of interferon-stimulated genes and histological evidence of focal encephalitis with recruitment of mononuclear cells to foci containing virus-infected cells. The morphogenesis of the cerebellum was delayed in infected animals. The defects in cerebellar development in infected animals were generalized and, although correlated temporally with virus replication and CNS inflammation, spatially unrelated to foci of virus-infected cells. Specific defects included decreased granular neuron proliferation and migration, expression of differentiation markers, and activation of neurotrophin receptors. These findings suggested that in the developing CNS, focal virus infection and induction of inflammatory responses in resident and infiltrating mononuclear cells resulted in delayed cerebellar morphogenesis. PMID:18268036

Chronic unpredictable stress decreases expression of brain-derived neurotrophic factor (BDNF) in mouse ovaries: relationship to oocytes developmental potential.

PubMed

Wu, Li-Min; Hu, Mei-Hong; Tong, Xian-Hong; Han, Hui; Shen, Ni; Jin, Ren-Tao; Wang, Wei; Zhou, Gui-Xiang; He, Guo-Ping; Liu, Yu-Sheng

2012-01-01

Brain-derived neurotropic factor (BDNF) was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary. Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA) axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated. Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn't affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment. BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress.

Chronic Unpredictable Stress Decreases Expression of Brain-Derived Neurotrophic Factor (BDNF) in Mouse Ovaries: Relationship to Oocytes Developmental Potential

PubMed Central

Tong, Xian-Hong; Han, Hui; Shen, Ni; Jin, Ren-Tao; Wang, Wei; Zhou, Gui-Xiang; He, Guo-Ping; Liu, Yu-Sheng

2012-01-01

Background Brain-derived neurotropic factor (BDNF) was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary. Methods Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA) axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated. Results Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn’t affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment. Conclusion BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress. PMID:23284991

SOX2 expression levels distinguish between neural progenitor populations of the developing dorsal telencephalon.

PubMed

Hutton, Scott R; Pevny, Larysa H

2011-04-01

The HMG-Box transcription factor SOX2 is expressed in neural progenitor populations throughout the developing and adult central nervous system and is necessary to maintain their progenitor identity. However, it is unclear whether SOX2 levels are uniformly expressed across all neural progenitor populations. In the developing dorsal telencephalon, two distinct populations of neural progenitors, radial glia and intermediate progenitor cells, are responsible for generating a majority of excitatory neurons found in the adult neocortex. Here we demonstrate, using both cellular and molecular analyses, that SOX2 is differentially expressed between radial glial and intermediate progenitor populations. Moreover, utilizing a SOX2(EGFP) mouse line, we show that this differential expression can be used to prospectively isolate distinct, viable populations of radial glia and intermediate cells for in vitro analysis. Given the limited repertoire of cell-surface markers currently available for neural progenitor cells, this provides an invaluable tool for prospectively identifying and isolating distinct classes of neural progenitor cells from the central nervous system. Copyright © 2011 Elsevier Inc. All rights reserved.

Central nervous system remyelination in culture--a tool for multiple sclerosis research.

PubMed

Zhang, Hui; Jarjour, Andrew A; Boyd, Amanda; Williams, Anna

2011-07-01

Multiple sclerosis is a demyelinating disease of the central nervous system which only affects humans. This makes it difficult to study at a molecular level, and to develop and test potential therapies that may change the course of the disease. The development of therapies to promote remyelination in multiple sclerosis is a key research aim, to both aid restoration of electrical impulse conduction in nerves and provide neuroprotection, reducing disability in patients. Testing a remyelination therapy in the many and various in vivo models of multiple sclerosis is expensive in terms of time, animals and money. We report the development and characterisation of an ex vivo slice culture system using mouse brain and spinal cord, allowing investigation of myelination, demyelination and remyelination, which can be used as an initial reliable screen to select the most promising remyelination strategies. We have automated the quantification of myelin to provide a high content and moderately-high-throughput screen for testing therapies for remyelination both by endogenous and exogenous means and as an invaluable way of studying the biology of remyelination. Copyright © 2011 Elsevier Inc. All rights reserved.

Central nervous system remyelination in culture — A tool for multiple sclerosis research

PubMed Central

Zhang, Hui; Jarjour, Andrew A.; Boyd, Amanda; Williams, Anna

2011-01-01

Multiple sclerosis is a demyelinating disease of the central nervous system which only affects humans. This makes it difficult to study at a molecular level, and to develop and test potential therapies that may change the course of the disease. The development of therapies to promote remyelination in multiple sclerosis is a key research aim, to both aid restoration of electrical impulse conduction in nerves and provide neuroprotection, reducing disability in patients. Testing a remyelination therapy in the many and various in vivo models of multiple sclerosis is expensive in terms of time, animals and money. We report the development and characterisation of an ex vivo slice culture system using mouse brain and spinal cord, allowing investigation of myelination, demyelination and remyelination, which can be used as an initial reliable screen to select the most promising remyelination strategies. We have automated the quantification of myelin to provide a high content and moderately-high-throughput screen for testing therapies for remyelination both by endogenous and exogenous means and as an invaluable way of studying the biology of remyelination. PMID:21515259

Function and regulation of heat shock factor 2 during mouse embryogenesis

PubMed Central

Rallu, M.; Loones, Mt.; Lallemand, Y.; Morimoto, R.; Morange, M.; Mezger, V.

1997-01-01

The spontaneous expression of heat shock genes during development is well documented in many animal species, but the mechanisms responsible for this developmental regulation are only poorly understood. In vertebrates, additional heat shock transcription factors, distinct from the heat shock factor 1 (HSF1) involved in the stress response, were suggested to be involved in this developmental control. In particular, the mouse HSF2 has been found to be active in testis and during preimplantation development. However, the role of HSF2 and its mechanism of activation have remained elusive due to the paucity of data on its expression during development. In this study, we have examined HSF2 expression during the postimplantation phase of mouse development. Our data show a developmental regulation of HSF2, which is expressed at least until 15.5 days of embryogenesis. It becomes restricted to the central nervous system during the second half of gestation. It is expressed in the ventricular layer of the neural tube which contains mitotically active cells but not in postmitotic neurons. Parallel results were obtained for mRNA, protein, and activity levels, demonstrating that the main level of control was transcriptional. The detailed analysis of the activity of a luciferase reporter gene under the control of the hsp70.1 promoter, as well as the description of the protein expression patterns of the major heat shock proteins in the central nervous system, show that HSF2 and heat shock protein expression domains do not coincide. This result suggests that HFS2 might be involved in other regulatory developmental pathways and paves the way to new functional approaches. PMID:9122205

Pleiotropy in microdeletion syndromes: Neurologic and spermatogenic abnormalities in mice homozygous for the p{sup 6H} deletion are likely due to dysfunction of a single gene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rinchik, E.M.; Carpenter, D.A.; Handel, M.A.

1995-07-03

Variability and complexity of phenotypes observed in microdeletion syndromes can be due to deletion of a single gene whose product participates in several aspects of development or can be due to the deletion of a number of tightly linked genes, each adding its own effect to the syndrome. The p{sup 6H} deletion in mouse chromosome 7 presents a good model with which to address this question of multigene vs. single-gene pleiotropy. Mice homozygous for the p{sup 6H} deletion are diluted in pigmentation, are smaller than their littermates, and manifest a nervous jerky-gait phenotype. Male homozygotes are sterile and exhibit profoundmore » abnormalities in spermiogenesis. By using N-ethyl-N-nitrosourea (EtNU) mutagenesis and a breeding protocol designed to recover recessive mutations expressed hemizygously opposite a large p-locus deletion, we have generated three noncomplementing mutations that map to the p{sup 6H} deletion. Each of these EtNU-induced mutations has adverse effects on the size, nervous behavior, and progression of spermiogenesis that characterize p{sup 6H} deletion homozygotes. Because etNU is thought to induce primarily intragenic (point) mutations in mouse stem-cell spermatogonia, we propose that the trio of phenotypes (runtiness, nervous jerky gait, and male sterility) expressed in p{sup 6H} deletion homozygotes is the result of deletion of a single highly pleiotropic gene. We also predict that a homologous single locus, quite possibly tightly linked and distal to the D15S12 (P) locus in human chromosome 15q11-q13, may be associated with similar developmental abnormalities in humans. 29 refs., 3 figs., 1 tab.« less

Model of pediatric pituitary hormone deficiency separates the endocrine and neural functions of the LHX3 transcription factor in vivo

PubMed Central

Colvin, Stephanie C.; Malik, Raleigh E.; Showalter, Aaron D.; Sloop, Kyle W.; Rhodes, Simon J.

2011-01-01

The etiology of most pediatric hormone deficiency diseases is poorly understood. Children with combined pituitary hormone deficiency (CPHD) have insufficient levels of multiple anterior pituitary hormones causing short stature, metabolic disease, pubertal failure, and often have associated nervous system symptoms. Mutations in developmental regulatory genes required for the specification of the hormone-secreting cell types of the pituitary gland underlie severe forms of CPHD. To better understand these diseases, we have created a unique mouse model of CPHD with a targeted knockin mutation (Lhx3 W227ter), which is a model for the human LHX3 W224ter disease. The LHX3 gene encodes a LIM-homeodomain transcription factor, which has essential roles in pituitary and nervous system development in mammals. The introduced premature termination codon results in deletion of the carboxyl terminal region of the LHX3 protein, which is critical for pituitary gene activation. Mice that lack all LHX3 function do not survive beyond birth. By contrast, the homozygous Lhx3 W227ter mice survive, but display marked dwarfism, thyroid disease, and female infertility. Importantly, the Lhx3 W227ter mice have no apparent nervous system deficits. The Lhx3 W227ter mouse model provides a unique array of hormone deficits and facilitates experimental approaches that are not feasible with human patients. These experiments demonstrate that the carboxyl terminus of the LHX3 transcription factor is not required for viability. More broadly, this study reveals that the in vivo actions of a transcription factor in different tissues are molecularly separable. PMID:21149718

Feasibility of a Short-Arm Centrifuge for Mouse Hypergravity Experiments.

PubMed

Morita, Hironobu; Obata, Koji; Abe, Chikara; Shiba, Dai; Shirakawa, Masaki; Kudo, Takashi; Takahashi, Satoru

2015-01-01

To elucidate the pure impact of microgravity on small mammals despite uncontrolled factors that exist in the International Space Station, it is necessary to construct a 1 g environment in space. The Japan Aerospace Exploration Agency has developed a novel mouse habitat cage unit that can be installed in the Cell Biology Experiment Facility in the Kibo module of the International Space Station. The Cell Biology Experiment Facility has a short-arm centrifuge to produce artificial 1 g gravity in space for mouse experiments. However, the gravitational gradient formed inside the rearing cage is larger when the radius of gyration is shorter; this may have some impact on mice. Accordingly, biological responses to hypergravity induced by a short-arm centrifuge were examined and compared with those induced by a long-arm centrifuge. Hypergravity induced a significant Fos expression in the central nervous system, a suppression of body mass growth, an acute and transient reduction in food intake, and impaired vestibulomotor coordination. There was no difference in these responses between mice raised in a short-arm centrifuge and those in a long-arm centrifuge. These results demonstrate the feasibility of using a short-arm centrifuge for mouse experiments.

Feasibility of a Short-Arm Centrifuge for Mouse Hypergravity Experiments

PubMed Central

Morita, Hironobu; Obata, Koji; Abe, Chikara; Shiba, Dai; Shirakawa, Masaki; Kudo, Takashi; Takahashi, Satoru

2015-01-01

To elucidate the pure impact of microgravity on small mammals despite uncontrolled factors that exist in the International Space Station, it is necessary to construct a 1 g environment in space. The Japan Aerospace Exploration Agency has developed a novel mouse habitat cage unit that can be installed in the Cell Biology Experiment Facility in the Kibo module of the International Space Station. The Cell Biology Experiment Facility has a short-arm centrifuge to produce artificial 1 g gravity in space for mouse experiments. However, the gravitational gradient formed inside the rearing cage is larger when the radius of gyration is shorter; this may have some impact on mice. Accordingly, biological responses to hypergravity induced by a short-arm centrifuge were examined and compared with those induced by a long-arm centrifuge. Hypergravity induced a significant Fos expression in the central nervous system, a suppression of body mass growth, an acute and transient reduction in food intake, and impaired vestibulomotor coordination. There was no difference in these responses between mice raised in a short-arm centrifuge and those in a long-arm centrifuge. These results demonstrate the feasibility of using a short-arm centrifuge for mouse experiments. PMID:26221724

Collagen 18 and agrin are secreted by neural crest cells to remodel their microenvironment and regulate their migration during enteric nervous system development.

PubMed

Nagy, Nandor; Barad, Csilla; Hotta, Ryo; Bhave, Sukhada; Arciero, Emily; Dora, David; Goldstein, Allan M

2018-05-08

The enteric nervous system (ENS) arises from neural crest cells that migrate, proliferate, and differentiate into enteric neurons and glia within the intestinal wall. Many extracellular matrix (ECM) components are present in the embryonic gut, but their role in regulating ENS development is largely unknown. Here, we identify heparan sulfate proteoglycan proteins, including collagen XVIII (Col18) and agrin, as important regulators of enteric neural crest-derived cell (ENCDC) development. In developing avian hindgut, Col18 is expressed at the ENCDC wavefront, while agrin expression occurs later. Both proteins are normally present around enteric ganglia, but are absent in aganglionic gut. Using chick-mouse intestinal chimeras and enteric neurospheres, we show that vagal- and sacral-derived ENCDCs from both species secrete Col18 and agrin. Whereas glia express Col18 and agrin, enteric neurons only express the latter. Functional studies demonstrate that Col18 is permissive whereas agrin is strongly inhibitory to ENCDC migration, consistent with the timing of their expression during ENS development. We conclude that ENCDCs govern their own migration by actively remodeling their microenvironment through secretion of ECM proteins. © 2018. Published by The Company of Biologists Ltd.

Elevated prostacyclin biosynthesis in mice impacts memory and anxiety-like behavior.

PubMed

Vollert, Craig; Ohia, Odochi; Akasaka, Hironari; Berridge, Casey; Ruan, Ke-He; Eriksen, Jason L

2014-01-01

Prostacyclin is an endogenous lipid metabolite with properties of vasodilation and anti-platelet aggregation. While the effects of prostacyclin on the vascular protection have been well-documented, the role of this eicosanoid in the central nervous system has not been extensively studied. Recently, a transgenic mouse containing a hybrid enzyme, of cyclooxygenase-1 linked to prostacyclin synthase, was developed that produces elevated levels of prostacyclin in vivo. The goal of this study was to investigate whether increased prostacyclin biosynthesis could affect behavioral phenotypes in mice. Our results uncovered that elevated levels of prostacyclin broadly affect both cognitive and non-cognitive behaviors, including decreased anxiety-like behavior and improved learning in the fear-conditioning memory test. This study demonstrates that prostacyclin plays an important, but previously unrecognized, role in central nervous system function and behavior. Copyright © 2013 Elsevier B.V. All rights reserved.

Effective components of Chinese herbs reduce central nervous system function decline induced by iron overload

PubMed Central

Dong, Xian-hui; Bai, Jiang-tao; Kong, Wei-na; He, Xiao-ping; Yan, Peng; Shao, Tie-mei; Yu, Wen-guo; Chai, Xi-qing; Wu, Yan-hua; Liu, Cong

2015-01-01

Abnormally increased levels of iron in the brain trigger cascade amplification in Alzheimer’s disease patients, resulting in neuronal death. This study investigated whether components extracted from the Chinese herbs epimedium herb, milkvetch root and kudzuvine root could relieve the abnormal expression of iron metabolism-related protein in Alzheimer’s disease patients. An APPswe/PS1ΔE9 double transgenic mouse model of Alzheimer’s disease was used. The intragastric administration of compounds from epimedium herb, milkvetch root and kudzuvine root improved pathological alterations such as neuronal edema, increased the number of neurons, downregulated divalent metal transporter 1 expression, upregulated ferroportin 1 expression, and inhibited iron overload in the cerebral cortex of mice with Alzheimer’s disease. These compounds reduced iron overload-induced impairment of the central nervous system, indicating a new strategy for developing novel drugs for the treatment of Alzheimer’s disease. PMID:26109953

Rare-earth Nanoparticle-induced Cytotoxicity on Spatial Cognition Memory of Mouse Brain.

PubMed

Lin, Cai-Hou; Liu, Gui-Fen; Chen, Jing; Chen, Yan; Lin, Ru-Hui; He, Hong-Xing; Chen, Jian-Ping

2017-11-20

Luminescent rare-earth-based nanoparticles have been increasingly used in nanomedicine due to their excellent physicochemical properties, such as biomedical imaging agents, drug carriers, and biomarkers. However, biological safety of the rare-earth-based nanomedicine is of great significance for future development in practical applications. In particular, biological effects of rare-earth nanoparticles on human's central nervous system are still unclear. This study aimed to investigate the potential toxicity of rare-earth nanoparticles in nervous system function in the case of continuous exposure. Adult ICR mice were randomly divided into seven groups, including control group (receiving 0.9% normal saline) and six experimental groups (10 mice in each group). Luminescent rare-earth-based nanoparticles were synthesized by a reported co-precipitation method. Two different sizes of the nanoparticles were obtained, and then exposed to ICR mice through caudal vein injection at 0.5, 1.0, and 1.5 mg/kg body weight in each day for 7 days. Next, a Morris water maze test was employed to evaluate impaired behaviors of their spatial recognition memory. Finally, histopathological examination was implemented to study how the nanoparticles can affect the brain tissue of the ICR mice. Two different sizes of rare-earth nanoparticles have been successfully obtained, and their physical properties including luminescence spectra and nanoparticle sizes have been characterized. In these experiments, the rare-earth nanoparticles were taken up in the mouse liver using the magnetic resonance imaging characterization. Most importantly, the experimental results of the Morris water maze tests and histopathological analysis clearly showed that rare-earth nanoparticles could induce toxicity on mouse brain and impair the behaviors of spatial recognition memory. Finally, the mechanism of adenosine triphosphate quenching by the rare-earth nanoparticles was provided to illustrate the toxicity on the mouse brain. This study suggested that long-term exposure of high-dose bare rare-earth nanoparticles caused an obvious damage on the spatial recognition memory in the mice.

Robo1/2 regulate follicle atresia through manipulating granulosa cell apoptosis in mice

PubMed Central

Li, Jiangchao; Ye, Yuxiang; Zhang, Renli; Zhang, Lili; Hu, Xiwen; Han, Dong; Chen, Jiayuan; He, Xiaodong; Wang, Guang; Yang, Xuesong; Wang, Lijing

2015-01-01

Secreted Slit proteins and their Roundabout (Robo) receptors act as a repulsive cue to preventaxons from migrating to inappropriate locations during the development of the nervous system. Slit/Robo has also been implicated in reproductive system development, but the molecular mechanism of the Slit/Robo pathway in the reproductive system remains poorly understood. Using a transgenic mouse model, we investigated the function of the Slit/Robo pathway on ovarian follicle development and atresia. We first demonstrated that more offspring were born to mice with a partial knockout of the Robo1/2 genes in mice. We next showed that Robo1 and Robo2 are strongly expressed in ovarian granulosacells. Apoptosis in granulosa cells was reduced when Robo1/2 were partially knocked out, and this observation was further verified by in vitro Robo1/2 knockout experiments in mouse and human granulosa cells. We also found that ovarian angiogenesis wasenhanced by a partial lack of Robo1/2 genes. In summary, our data suggest that the Slit/Robo pathway can impact follicle development and atresia by influencinggranulosa cell apoptosis. PMID:25988316

Characterization of individual mouse cerebrospinal fluid proteomes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Jeffrey S.; Angel, Thomas E.; Chavkin, Charles

2014-03-20

Analysis of cerebrospinal fluid (CSF) offers key insight into the status of the central nervous system. Characterization of murine CSF proteomes can provide a valuable resource for studying central nervous system injury and disease in animal models. However, the small volume of CSF in mice has thus far limited individual mouse proteome characterization. Through non-terminal CSF extractions in C57Bl/6 mice and high-resolution liquid chromatography-mass spectrometry analysis of individual murine samples, we report the most comprehensive proteome characterization of individual murine CSF to date. Utilizing stringent protein inclusion criteria that required the identification of at least two unique peptides (1% falsemore » discovery rate at the peptide level) we identified a total of 566 unique proteins, including 128 proteins from three individual CSF samples that have been previously identified in brain tissue. Our methods and analysis provide a mechanism for individual murine CSF proteome analysis.« less

Neurological disease in man following administration of suckling mouse brain antirabies vaccine.

PubMed

Held, J R; Adaros, H L

1972-01-01

In Latin America, suckling mouse brain (SMB) vaccine has become the most commonly used vaccine for immunization of both man and animals against rabies. This vaccine is highly immunogenic, is relatively economical and easy to produce, and is believed to be free of the immunoencephalitogenic factor. From 1964 to the end of 1969, there were 40 reported cases of neurological disease following administration of SMB vaccine, 32 of which met the criteria for inclusion in this report. These 32 cases occurred in 8 different countries. In contrast to neurological disease following the administration of other types of nervous tissue vaccine, the majority of the cases following vaccination with SMB vaccine had a Guillain-Barré-type syndrome with peripheral nervous system involvement and a higher case-fatality rate. The causative agent has not been demonstrated. Modifications in the production and handling of the vaccine may be producing changes that are responsible.

BDNF and its pro-peptide are stored in presynaptic dense core vesicles in brain neurons

PubMed Central

Dieni, Sandra; Matsumoto, Tomoya; Dekkers, Martijn; Rauskolb, Stefanie; Ionescu, Mihai S.; Deogracias, Ruben; Gundelfinger, Eckart D.; Kojima, Masami; Nestel, Sigrun; Frotscher, Michael

2012-01-01

Although brain-derived neurotrophic factor (BDNF) regulates numerous and complex biological processes including memory retention, its extremely low levels in the mature central nervous system have greatly complicated attempts to reliably localize it. Using rigorous specificity controls, we found that antibodies reacting either with BDNF or its pro-peptide both stained large dense core vesicles in excitatory presynaptic terminals of the adult mouse hippocampus. Both moieties were ∼10-fold more abundant than pro-BDNF. The lack of postsynaptic localization was confirmed in Bassoon mutants, a seizure-prone mouse line exhibiting markedly elevated levels of BDNF. These findings challenge previous conclusions based on work with cultured neurons, which suggested activity-dependent dendritic synthesis and release of BDNF. They instead provide an ultrastructural basis for an anterograde mode of action of BDNF, contrasting with the long-established retrograde model derived from experiments with nerve growth factor in the peripheral nervous system. PMID:22412021

Transcriptomic profile analysis of mouse neural tube development by RNA-Seq.

PubMed

Yu, Juan; Mu, Jianbing; Guo, Qian; Yang, Lihong; Zhang, Juan; Liu, Zhizhen; Yu, Baofeng; Zhang, Ting; Xie, Jun

2017-09-01

The neural tube is the primordium of the central nervous system (CNS) in which its development is not entirely clear. Understanding the cellular and molecular basis of neural tube development could, therefore, provide vital clues to the mechanism of neural tube defects (NTDs). Here, we investigated the gene expression profiles of three different time points (embryonic day (E) 8.5, 9.5 and 10.5) of mouse neural tube by using RNA-seq approach. About 391 differentially expressed genes (DEGs) were screened during mouse neural tube development, including 45 DEGs involved in CNS development, among which Bmp2, Ascl1, Olig2, Lhx1, Wnt7b and Eomes might play the important roles. Of 45 DEGs, Foxp2, Eomes, Hoxb3, Gpr56, Hap1, Nkx2-1, Sez6l2, Wnt7b, Tbx20, Nfib, Cntn1 and Dcx had different isoforms, and the opposite expression pattern of different isoforms was observed for Gpr56, Nkx2-1 and Sez6l2. In addition, alternative splicing, such as mutually exclusive exon, retained intron, skipped exon and alternative 3' splice site was identified in 10 neural related differentially splicing genes, including Ngrn, Ddr1, Dctn1, Dnmt3b, Ect2, Map2, Mbnl1, Meis2, Vcan and App. Moreover, seven neural splicing factors, such as Nova1/2, nSR100/Srrm4, Elavl3/4, Celf3 and Rbfox1 were differentially expressed during mouse neural tube development. Interestingly, nine DEGs identified above were dysregulated in retinoic acid-induced NTDs model, indicating the possible important role of these genes in NTDs. Taken together, our study provides more comprehensive information on mouse neural tube development, which might provide new insights on NTDs occurrence. © 2017 IUBMB Life, 69(9):706-719, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

A potential inhibitory function of draxin in regulating mouse trunk neural crest migration.

PubMed

Zhang, Sanbing; Su, Yuhong; Gao, Jinbao; Zhang, Chenbing; Tanaka, Hideaki

2017-01-01

Draxin is a repulsive axon guidance protein that plays important roles in the formation of three commissures in the central nervous system and dorsal interneuron 3 (dI3) in the chick spinal cord. In the present study, we report the expression pattern of mouse draxin in the embryonic mouse trunk spinal cord. In the presence of draxin, the longest net migration length of a migrating mouse trunk neural crest cell was significantly reduced. In addition, the relative number of apolar neural crest cells increased as the draxin treatment time increased. Draxin caused actin cytoskeleton rearrangement in the migrating trunk neural crest cells. Our data suggest that draxin may regulate mouse trunk neural crest cell migration by the rearrangement of cell actin cytoskeleton and by reducing the polarization activity of these cells subsequently.

A versatile clearing agent for multi-modal brain imaging

PubMed Central

Costantini, Irene; Ghobril, Jean-Pierre; Di Giovanna, Antonino Paolo; Mascaro, Anna Letizia Allegra; Silvestri, Ludovico; Müllenbroich, Marie Caroline; Onofri, Leonardo; Conti, Valerio; Vanzi, Francesco; Sacconi, Leonardo; Guerrini, Renzo; Markram, Henry; Iannello, Giulio; Pavone, Francesco Saverio

2015-01-01

Extensive mapping of neuronal connections in the central nervous system requires high-throughput µm-scale imaging of large volumes. In recent years, different approaches have been developed to overcome the limitations due to tissue light scattering. These methods are generally developed to improve the performance of a specific imaging modality, thus limiting comprehensive neuroanatomical exploration by multi-modal optical techniques. Here, we introduce a versatile brain clearing agent (2,2′-thiodiethanol; TDE) suitable for various applications and imaging techniques. TDE is cost-efficient, water-soluble and low-viscous and, more importantly, it preserves fluorescence, is compatible with immunostaining and does not cause deformations at sub-cellular level. We demonstrate the effectiveness of this method in different applications: in fixed samples by imaging a whole mouse hippocampus with serial two-photon tomography; in combination with CLARITY by reconstructing an entire mouse brain with light sheet microscopy and in translational research by imaging immunostained human dysplastic brain tissue. PMID:25950610

CD44-positive cells are candidates for astrocyte precursor cells in developing mouse cerebellum.

PubMed

Cai, Na; Kurachi, Masashi; Shibasaki, Koji; Okano-Uchida, Takayuki; Ishizaki, Yasuki

2012-03-01

Neural stem cells are generally considered to be committed to becoming precursor cells before terminally differentiating into either neurons or glial cells during neural development. Neuronal and oligodendrocyte precursor cells have been identified in several areas in the murine central nervous system. The presence of astrocyte precursor cells (APCs) is not so well understood. The present study provides several lines of evidence that CD44-positive cells are APCs in the early postnatal mouse cerebellum. In developing mouse cerebellum, CD44-positive cells, mostly located in the white matter, were positive for the markers of the astrocyte lineage, but negative for the markers of mature astrocytes. CD44-positive cells were purified from postnatal cerebellum by fluorescence-activated cell sorting and characterized in vitro. In the absence of any signaling molecule, many cells died by apoptosis. The surviving cells gradually expressed glial fibrillary acidic protein, a marker for mature astrocytes, indicating that differentiation into mature astrocytes is the default program for these cells. The cells produced no neurospheres nor neurons nor oligodendrocytes under any condition examined, indicating these cells are not neural stem cells. Leukemia inhibitory factor greatly promoted astrocytic differentiation of CD44-positive cells, whereas bone morphogenetic protein 4 (BMP4) did not. Fibroblast growth factor-2 was a potent mitogen for these cells, but was insufficient for survival. BMP4 inhibited activation of caspase-3 and greatly promoted survival, suggesting a novel role for BMP4 in the control of development of astrocytes in cerebellum. We isolated and characterized only CD44 strongly positive large cells and discarded small and/or CD44 weakly positive cells in this study. Further studies are necessary to characterize these cells to help determine whether CD44 is a selective and specific marker for APCs in the developing mouse cerebellum. In conclusion, we succeeded in preparing APC candidates from developing mouse cerebellum, characterized them in vitro, and found that BMPs are survival factors for these cells.

Improvement of Learning and Memory Induced by Cordyceps Polypeptide Treatment and the Underlying Mechanism

PubMed Central

2018-01-01

Our previous research revealed that Cordyceps militaris can improve the learning and memory, and although the main active ingredient should be its polypeptide complexes, the underlying mechanism of its activity remains poorly understood. In this study, we explored the mechanisms by which Cordyceps militaris improves learning and memory in a mouse model. Mice were given scopolamine hydrobromide intraperitoneally to establish a mouse model of learning and memory impairment. The effects of Cordyceps polypeptide in this model were tested using the Morris water maze test; serum superoxide dismutase activity; serum malondialdehyde levels; activities of acetyl cholinesterase, Na+-k+-ATPase, and nitric oxide synthase; and gamma aminobutyric acid and glutamate contents in brain tissue. Moreover, differentially expressed genes and the related cellular signaling pathways were screened using an mRNA expression profile chip. The results showed that the genes Pik3r5, Il-1β, and Slc18a2 were involved in the effects of Cordyceps polypeptide on the nervous system of these mice. Our findings suggest that Cordyceps polypeptide may improve learning and memory in the scopolamine-induced mouse model of learning and memory impairment by scavenging oxygen free radicals, preventing oxidative damage, and protecting the nervous system. PMID:29736181

Application of Targeted Mass Spectrometry for the Quantification of Sirtuins in the Central Nervous System

NASA Astrophysics Data System (ADS)

Jayasena, T.; Poljak, A.; Braidy, N.; Zhong, L.; Rowlands, B.; Muenchhoff, J.; Grant, R.; Smythe, G.; Teo, C.; Raftery, M.; Sachdev, P.

2016-10-01

Sirtuin proteins have a variety of intracellular targets, thereby regulating multiple biological pathways including neurodegeneration. However, relatively little is currently known about the role or expression of the 7 mammalian sirtuins in the central nervous system. Western blotting, PCR and ELISA are the main techniques currently used to measure sirtuin levels. To achieve sufficient sensitivity and selectivity in a multiplex-format, a targeted mass spectrometric assay was developed and validated for the quantification of all seven mammalian sirtuins (SIRT1-7). Quantification of all peptides was by multiple reaction monitoring (MRM) using three mass transitions per protein-specific peptide, two specific peptides for each sirtuin and a stable isotope labelled internal standard. The assay was applied to a variety of samples including cultured brain cells, mammalian brain tissue, CSF and plasma. All sirtuin peptides were detected in the human brain, with SIRT2 being the most abundant. Sirtuins were also detected in human CSF and plasma, and guinea pig and mouse tissues. In conclusion, we have successfully applied MRM mass spectrometry for the detection and quantification of sirtuin proteins in the central nervous system, paving the way for more quantitative and functional studies.

The extracellular Leucine-Rich Repeat superfamily; a comparative survey and analysis of evolutionary relationships and expression patterns

PubMed Central

Dolan, Jackie; Walshe, Karen; Alsbury, Samantha; Hokamp, Karsten; O'Keeffe, Sean; Okafuji, Tatsuya; Miller, Suzanne FC; Tear, Guy; Mitchell, Kevin J

2007-01-01

Background Leucine-rich repeats (LRRs) are highly versatile and evolvable protein-ligand interaction motifs found in a large number of proteins with diverse functions, including innate immunity and nervous system development. Here we catalogue all of the extracellular LRR (eLRR) proteins in worms, flies, mice and humans. We use convergent evidence from several transmembrane-prediction and motif-detection programs, including a customised algorithm, LRRscan, to identify eLRR proteins, and a hierarchical clustering method based on TribeMCL to establish their evolutionary relationships. Results This yields a total of 369 proteins (29 in worm, 66 in fly, 135 in mouse and 139 in human), many of them of unknown function. We group eLRR proteins into several classes: those with only LRRs, those that cluster with Toll-like receptors (Tlrs), those with immunoglobulin or fibronectin-type 3 (FN3) domains and those with some other domain. These groups show differential patterns of expansion and diversification across species. Our analyses reveal several clusters of novel genes, including two Elfn genes, encoding transmembrane proteins with eLRRs and an FN3 domain, and six genes encoding transmembrane proteins with eLRRs only (the Elron cluster). Many of these are expressed in discrete patterns in the developing mouse brain, notably in the thalamus and cortex. We have also identified a number of novel fly eLRR proteins with discrete expression in the embryonic nervous system. Conclusion This study provides the necessary foundation for a systematic analysis of the functions of this class of genes, which are likely to include prominently innate immunity, inflammation and neural development, especially the specification of neuronal connectivity. PMID:17868438

Angubindin-1 opens the blood-brain barrier in vivo for delivery of antisense oligonucleotide to the central nervous system.

PubMed

Zeniya, Satoshi; Kuwahara, Hiroya; Daizo, Kaiichi; Watari, Akihiro; Kondoh, Masuo; Yoshida-Tanaka, Kie; Kaburagi, Hidetoshi; Asada, Ken; Nagata, Tetsuya; Nagahama, Masahiro; Yagi, Kiyohito; Yokota, Takanori

2018-05-17

Within the field of RNA therapeutics, antisense oligonucleotide-based therapeutics are a potentially powerful means of treating intractable diseases. However, if these therapeutics are used for the treatment of neurological disorders, safe yet efficient methods of delivering antisense oligonucleotides across the blood-brain barrier to the central nervous system must be developed. Here, we examined the use of angubindin-1, a binder to the tricellular tight junction, to modulate paracellular transport between brain microvascular endothelial cells in the blood-brain barrier for the delivery of antisense oligonucleotides to the central nervous system. This proof-of-concept study demonstrated that intravenously injected angubindin-1 increased the permeability of the blood-brain barrier and enabled transient delivery of subsequently administered antisense oligonucleotides into the mouse brain and spinal cord, leading to silencing of a target RNA without any overt adverse effects. We also found that two bicellular tight junction modulators did not produce such a silencing effect, suggesting that the tricellular tight junction is likely a better target for the delivery of antisense oligonucleotides than the bicellular tight junction. Our delivery strategy of modulating the tricellular tight junction in the blood-brain barrier via angubindin-1 provides a novel avenue of research for the development of antisense oligonucleotide-based therapeutics for the treatment of neurological disorders. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

IRS-PCR-based genetic mapping of the huntingtin interacting protein gene (HIP1) on mouse chromosome 5.

PubMed

Himmelbauer, H; Wedemeyer, N; Haaf, T; Wanker, E E; Schalkwyk, L C; Lehrach, H

1998-01-01

Huntington's disease (HD) is a devastating central nervous system disorder. Even though the gene responsible has been positionally cloned recently, its etiology has remained largely unclear. To investigate potential disease mechanisms, we conducted a search for binding partners of the HD-protein huntingtin. With the yeast two-hybrid system, one such interacting factor, the huntingtin interacting protein-1 (HIP-1), was identified (Wanker et al. 1997; Kalchman et al. 1997) and the human gene mapped to 7q11.2. In this paper we demonstrate the localization of the HIP1 mouse homologue (Hip1) into a previously identified region of human-mouse synteny on distal mouse Chromosome (Chr) 5, both employing an IRS-PCR-based mapping strategy and traditional fluorescent in situ hybridization (FISH) mapping.

Adult mouse brain gene expression patterns bear an embryologic imprint

PubMed Central

Zapala, Matthew A.; Hovatta, Iiris; Ellison, Julie A.; Wodicka, Lisa; Del Rio, Jo A.; Tennant, Richard; Tynan, Wendy; Broide, Ron S.; Helton, Rob; Stoveken, Barbara S.; Winrow, Christopher; Lockhart, Daniel J.; Reilly, John F.; Young, Warren G.; Bloom, Floyd E.; Lockhart, David J.; Barlow, Carrolee

2005-01-01

The current model to explain the organization of the mammalian nervous system is based on studies of anatomy, embryology, and evolution. To further investigate the molecular organization of the adult mammalian brain, we have built a gene expression-based brain map. We measured gene expression patterns for 24 neural tissues covering the mouse central nervous system and found, surprisingly, that the adult brain bears a transcriptional “imprint” consistent with both embryological origins and classic evolutionary relationships. Embryonic cellular position along the anterior–posterior axis of the neural tube was shown to be closely associated with, and possibly a determinant of, the gene expression patterns in adult structures. We also observed a significant number of embryonic patterning and homeobox genes with region-specific expression in the adult nervous system. The relationships between global expression patterns for different anatomical regions and the nature of the observed region-specific genes suggest that the adult brain retains a degree of overall gene expression established during embryogenesis that is important for regional specificity and the functional relationships between regions in the adult. The complete collection of extensively annotated gene expression data along with data mining and visualization tools have been made available on a publicly accessible web site (www.barlow-lockhart-brainmapnimhgrant.org). PMID:16002470

The human natural killer-1 (HNK-1) glycan mimetic ursolic acid promotes functional recovery after spinal cord injury in mouse.

PubMed

Sahu, Sudhanshu; Li, Rong; Kadeyala, Praveen Kumar; Liu, Shisong; Schachner, Melitta

2018-05-01

Human natural killer-1 (HNK-1) cell antigen is a glycan epitope involved in several neural events, such as neuritogenesis, myelination, synaptic plasticity and regeneration of the nervous system after injury. We have recently identified the small organic compound ursolic acid (UA) as a HNK-1 mimetic with the aim to test its therapeutic potential in the central nervous system. UA, a plant-derived pentacyclic triterpenoid, is well known for its multiple biological functions, including neuroprotective, antioxidant and anti-inflammatory activities. In the present study, we evaluated its functions in a mouse model of spinal cord injury (SCI) and explored the molecular mechanisms underlying its positive effects. Oral administration of UA to mice 1 h after SCI and thereafter once daily for 6 weeks enhanced the regaining of motor functions and axonal regrowth, and decreased astrogliosis. UA administration decreased levels of proinflammatory markers, including interleukin-6 and tumor necrosis factor-α, in the injured spinal cord at the acute phase of inflammation and activated the mitogen-activated protein kinase and phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathways in the injured spinal cord. Taken together, these results suggest that UA may be a candidate for treatment of nervous system injuries. Copyright © 2017. Published by Elsevier Inc.

Angiogenesis within the developing mouse neural tube is dependent on sonic hedgehog signaling: possible roles of motor neurons.

PubMed

Nagase, Takashi; Nagase, Miki; Yoshimura, Kotaro; Fujita, Toshiro; Koshima, Isao

2005-06-01

Embryonic morphogenesis of vascular and nervous systems is tightly coordinated, and recent studies revealed that some neurogenetic factors such as Sonic hedgehog (Shh) also exhibit angiogenetic potential. Vascularization within the developing mouse neural tube depends on vessel sprouting from the surrounding vascular plexus. Previous studies implicated possible roles of VEGF/Flk-1 and Angiopoietin-1(Ang-1)/Tie-2 signaling as candidate molecules functioning in this process. Examining gene expressions of these factors at embryonic day (E) 9.5 and 10.5, we unexpectedly found that both VEGF and Ang-1 were expressed in the motor neurons in the ventral neural tube. The motor neurons were indeed located in the close vicinity of the infiltrating vessels, suggesting involvement of motor neurons in the sprouting. To substantiate this possibility, we inhibited induction of the motor neurons in the cultured mouse embryos by cyclopamine, a Shh signaling blocker. The vessel sprouting was dramatically impaired by inhibition of Shh signaling, together with nearly complete loss of the motor neurons. Expression of Ang-1, but not VEGF, within the neural tube was remarkably reduced in the cyclopamine treated embryos. These results suggest that the neural tube angiogenesis is dependent on Shh signaling, and mediated, at least in part, by the Ang-1 positive motor neurons.

Molecular cloning, structure, and chromosomal localization of the mouse LIM/homeobox gene Lhx5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bertuzzi, S.; Sheng, Hui Z.; Westphal, H.

1996-09-01

Lhx5, the mouse ortholog of the Xenopus Xlim-5, is a LIM/homeobox gene expressed in the central nervous system during both embryonic development and adulthood. During development its domain of expression is mainly localized at the most anterior portion of the neural tube, and it precedes the morphological differentiation of the forebrain; for this reason we believe that Lhx5 could play an important role in forebrain patterning. Here we present the structural organization and the chromosomal localization of the Lhx5 gene. The gene is composed of five exons spanning more than 10 kb of genomic sequence. The first and second LIMmore » domains are encoded by the first and second exon, while the codons of the homeobox are split between the third and the fourth exons. The structure of Lhx5 is similar to that of other LIM/homeodomain proteins, Lxh1/lim1 and Lhx3/lim3, but differs from that of other LIM genes, such as mec3 and LMO1/Rbtn1, in which the codons for the LIM domains are interrupted by introns. We have mapped Lhx5 to the central region of mouse chromosome 5. 38 refs., 4 figs.« less

Stimulated single fiber electromyography in the mouse: techniques and normative data

NASA Technical Reports Server (NTRS)

Gooch, C. L.; Mosier, D. R.

2001-01-01

As the number of new transgenic mouse models of human neuromuscular disease continues to increase, the development of sophisticated electrophysiologic techniques for assessing the peripheral nervous system in these models has become important. Neuromuscular junction (NMJ) dysfunction, in particular, is often not detectable by morphologic or other techniques. To enable sensitive testing of murine NMJ function, we developed and tested a method for stimulated single fiber electromyography (S-SFEMG) in the gastrocnemius muscles of anesthetized mice. Jitter was assessed by measuring the mean consecutive latency difference (MCD) of single fiber responses to sciatic nerve stimulation at 2 HZ. Mean MCD values in normothermic mice were in the range of 6-8 micros for different strains, with no MCD values exceeding 25 micros. Reduced core temperature (to 29 degrees--30 degrees C) resulted in increased jitter, whereas intubation and mechanical ventilation of mice did not alter these values. Intraperitoneal and intravenous injection of vecuronium, however, resulted in progressively increased jitter followed by blocking in continuously monitored fibers. These observations validate the utility of S-SFEMG in mice as an index of NMJ function under a variety of physiologic conditions, and suggest that a high safety factor for neuromuscular transmission exists at mouse NMJs. Copyright 2001 John Wiley & Sons, Inc.

In Silico Prediction and Validation of Gfap as an miR-3099 Target in Mouse Brain.

PubMed

Abidin, Shahidee Zainal; Leong, Jia-Wen; Mahmoudi, Marzieh; Nordin, Norshariza; Abdullah, Syahril; Cheah, Pike-See; Ling, King-Hwa

2017-08-01

MicroRNAs are small non-coding RNAs that play crucial roles in the regulation of gene expression and protein synthesis during brain development. MiR-3099 is highly expressed throughout embryogenesis, especially in the developing central nervous system. Moreover, miR-3099 is also expressed at a higher level in differentiating neurons in vitro, suggesting that it is a potential regulator during neuronal cell development. This study aimed to predict the target genes of miR-3099 via in-silico analysis using four independent prediction algorithms (miRDB, miRanda, TargetScan, and DIANA-micro-T-CDS) with emphasis on target genes related to brain development and function. Based on the analysis, a total of 3,174 miR-3099 target genes were predicted. Those predicted by at least three algorithms (324 genes) were subjected to DAVID bioinformatics analysis to understand their overall functional themes and representation. The analysis revealed that nearly 70% of the target genes were expressed in the nervous system and a significant proportion were associated with transcriptional regulation and protein ubiquitination mechanisms. Comparison of in situ hybridization (ISH) expression patterns of miR-3099 in both published and in-house-generated ISH sections with the ISH sections of target genes from the Allen Brain Atlas identified 7 target genes (Dnmt3a, Gabpa, Gfap, Itga4, Lxn, Smad7, and Tbx18) having expression patterns complementary to miR-3099 in the developing and adult mouse brain samples. Of these, we validated Gfap as a direct downstream target of miR-3099 using the luciferase reporter gene system. In conclusion, we report the successful prediction and validation of Gfap as an miR-3099 target gene using a combination of bioinformatics resources with enrichment of annotations based on functional ontologies and a spatio-temporal expression dataset.

The role of the immune system in neurofibromatosis type 1-associated nervous system tumors.

PubMed

Karmakar, Souvik; Reilly, Karlyne M

2017-01-01

With the recent development of new anticancer therapies targeting the immune system, it is important to understand which immune cell types and cytokines play critical roles in suppressing or promoting tumorigenesis. The role of mast cells in promoting neurofibroma growth in neurofibromatosis type 1 (NF1) patients was hypothesized decades ago. More recent experiments in mouse models have demonstrated the causal role of mast cells in neurofibroma development and of microglia in optic pathway glioma development. We review here what is known about the role of NF1 mutation in immune cell function and the role of immune cells in promoting tumorigenesis in NF1. We also review the therapies targeting immune cell pathways and their promise in NF1 tumors.

Expression profiling of peroxisome proliferator-activated receptor-delta (PPAR-delta) in mouse tissues using tissue microarray.

PubMed

Higashiyama, Hiroyuki; Billin, Andrew N; Okamoto, Yuji; Kinoshita, Mine; Asano, Satoshi

2007-05-01

Peroxisome proliferator-activated receptor-delta (PPAR-delta) is known as a transcription factor involved in the regulation of fatty acid oxidation and mitochondrial biogenesis in several tissues, such as skeletal muscle, liver and adipose tissues. In this study, to elucidate systemic physiological functions of PPAR-delta, we examined the tissue distribution and localization of PPAR-delta in adult mouse tissues using tissue microarray (TMA)-based immunohistochemistry. PPAR-delta positive signals were observed on variety of tissues/cells in multiple systems including cardiovascular, urinary, respiratory, digestive, endocrine, nervous, hematopoietic, immune, musculoskeletal, sensory and reproductive organ systems. In these organs, PPAR-delta immunoreactivity was generally localized on the nucleus, although cytoplasmic localization was observed on several cell types including neurons in the nervous system and cells of the islet of Langerhans. These expression profiling data implicate various physiological roles of PPAR-delta in multiple organ systems. TMA-based immunohistochemistry enables to profile comprehensive protein localization and distribution in a high-throughput manner.

A comparative study of the effects of sparteine, lupanine and lupin extract on the central nervous system of the mouse.

PubMed

Pothier, J; Cheav, S L; Galand, N; Dormeau, C; Viel, C

1998-08-01

Lupin is toxic because of its alkaloid content, sparteine and lupanine in particular. Although the pharmacological properties of sparteine are well known those of lupanine have not been much studied. This paper reports procedures for extraction, purification and crystallization of lupanine, and methods for the preparation of an extract for injection of Lupinus mutabilis Sweet, and for the determination of the acute toxicity and maximum non-lethal dose (DL0) of lupanine, sparteine and lupin extract in the mouse. The three substances were tested on the central nervous system (CNS) for locomotor activity, for interaction with specific drugs used for treatment of the CNS (the stimulant drugs amphetamine and pentetrazol and the depressant drugs pentobarbital and chlorpromazine) and for analgesic activity. The results indicate that lupanine and lupin extract are less toxic than sparteine and that at the doses studied the three products have a weak sedative effect on the CNS.

Distribution of serine/threonine kinase SAD-B in mouse peripheral nerve synapse.

PubMed

Hagiwara, Akari; Harada, Kenu; Hida, Yamato; Kitajima, Isao; Ohtsuka, Toshihisa

2011-05-11

The serine/threonine kinase SAD regulates neural functions such as axon/dendrite polarization and neurotransmitter release. In the vertebrate central nervous system, SAD-B, a homolog of Caenorhabditis elegans SAD-1, is associated with synaptic vesicles and the active zone cytomatrix in nerve terminals. However, the distribution of SAD-B in the peripheral nervous system remains elusive. Here, we show that SAD-B is specifically localized to neuromuscular junctions. Although the active zone protein bassoon showed a punctated signal indicating its localization to motor end plates, SAD-B shows relatively diffuse localization indicating its association with both the active zone and synaptic vesicles. Therefore, SAD kinase may regulate neurotransmitter release from motor end plates in a similar manner to its regulation of neurotransmitter release in the central nervous system.

Myelin-oligodendrocyte glycoprotein is a member of a subset of the immunoglobulin superfamily encoded within the major histocompatibility complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pham-Dinh, D.; Dautigny, A.; Mattei, M.G.

1993-09-01

Myelin/oligodendrocyte glycoprotein (MOG) is found on the surface of myelinating oligodendrocytes and external lamellae of myelin sheaths in the central nervous system, and it is target antigen in experimental autoimmune encephalomyelitis and multiple sclerosis. The authors have isolated bovine, mouse, and rat MOG cDNA clones and shown that the developmental pattern of MOG expression in the rat central nervous system coincides with the late stages of myelination. The amino-terminal, extracellular domain of MOG has characteristics of an immunoglobulin variable domain and is 46% and 41% identical with the amino terminus of bovine butyrophilin (expressed in the lactating mammary gland) andmore » B-G antigens of the chicken major histocompatibility complex (MHC), respectively; these proteins thus form a subset of the immunoglobulin superfamily. The homology between MOG and B-G extends beyond their structure and genetic mapping to their ability to induce strong antibody responses and has implications for the role of MOG in pathological, autoimmune conditions. The authors colocalized the MOG and BT genes to the human MHC on chromosome 6p21.3-p22. The mouse MOG gene was mapped to the homologous band C of chromosome 17, within the M region of the mouse MHC. 38 refs., 6 figs.« less

SPED light sheet microscopy: fast mapping of biological system structure and function

PubMed Central

Tomer, Raju; Lovett-Barron, Matthew; Kauvar, Isaac; Andalman, Aaron; Burns, Vanessa M.; Sankaran, Sethuraman; Grosenick, Logan; Broxton, Michael; Yang, Samuel; Deisseroth, Karl

2016-01-01

The goal of understanding living nervous systems has driven interest in high-speed and large field-of-view volumetric imaging at cellular resolution. Light-sheet microscopy approaches have emerged for cellular-resolution functional brain imaging in small organisms such as larval zebrafish, but remain fundamentally limited in speed. Here we have developed SPED light sheet microscopy, which combines large volumetric field-of-view via an extended depth of field with the optical sectioning of light sheet microscopy, thereby eliminating the need to physically scan detection objectives for volumetric imaging. SPED enables scanning of thousands of volumes-per-second, limited only by camera acquisition rate, through the harnessing of optical mechanisms that normally result in unwanted spherical aberrations. We demonstrate capabilities of SPED microscopy by performing fast sub-cellular resolution imaging of CLARITY mouse brains and cellular-resolution volumetric Ca2+ imaging of entire zebrafish nervous systems. Together, SPED light sheet methods enable high-speed cellular-resolution volumetric mapping of biological system structure and function. PMID:26687363

Dysregulation of the Cytokine GM-CSF Induces Spontaneous Phagocyte Invasion and Immunopathology in the Central Nervous System.

PubMed

Spath, Sabine; Komuczki, Juliana; Hermann, Mario; Pelczar, Pawel; Mair, Florian; Schreiner, Bettina; Becher, Burkhard

2017-02-21

Chronic inflammatory diseases are influenced by dysregulation of cytokines. Among them, granulocyte macrophage colony stimulating factor (GM-CSF) is crucial for the pathogenic function of T cells in preclinical models of autoimmunity. To study the impact of dysregulated GM-CSF expression in vivo, we generated a transgenic mouse line allowing the induction of GM-CSF expression in mature, peripheral helper T (Th) cells. Antigen-independent GM-CSF release led to the invasion of inflammatory myeloid cells into the central nervous system (CNS), which was accompanied by the spontaneous development of severe neurological deficits. CNS-invading phagocytes produced reactive oxygen species and exhibited a distinct genetic signature compared to myeloid cells invading other organs. We propose that the CNS is particularly vulnerable to the attack of monocyte-derived phagocytes and that the effector functions of GM-CSF-expanded myeloid cells are in turn guided by the tissue microenvironment. Copyright © 2017 Elsevier Inc. All rights reserved.

The autonomic nervous system and cardiac GLP-1 receptors control heart rate in mice.

PubMed

Baggio, Laurie L; Ussher, John R; McLean, Brent A; Cao, Xiemin; Kabir, M Golam; Mulvihill, Erin E; Mighiu, Alexandra S; Zhang, Hangjun; Ludwig, Andreas; Seeley, Randy J; Heximer, Scott P; Drucker, Daniel J

2017-11-01

Glucagon-like peptide-1 (GLP-1) is secreted from enteroendocrine cells and exerts a broad number of metabolic actions through activation of a single GLP-1 receptor (GLP-1R). The cardiovascular actions of GLP-1 have garnered increasing attention as GLP-1R agonists are used to treat human subjects with diabetes and obesity that may be at increased risk for development of heart disease. Here we studied mechanisms linking GLP-1R activation to control of heart rate (HR) in mice. The actions of GLP-1R agonists were examined on the control of HR in wild type mice (WT) and in mice with cardiomyocyte-selective disruption of the GLP-1R (Glp1r CM-/- ). Complimentary studies examined the effects of GLP-1R agonists in mice co-administered propranolol or atropine. The direct effects of GLP-1R agonism on HR and ventricular developed pressure were examined in isolated perfused mouse hearts ex vivo, and atrial depolarization was quantified in mouse hearts following direct application of liraglutide to perfused atrial preparations ex vivo. Doses of liraglutide and lixisenatide that were equipotent for acute glucose control rapidly increased HR in WT and Glp1r CM-/- mice in vivo. The actions of liraglutide to increase HR were more sustained relative to lixisenatide, and diminished in Glp1r CM-/- mice. The acute chronotropic actions of GLP-1R agonists were attenuated by propranolol but not atropine. Neither native GLP-1 nor lixisenatide increased HR or developed pressure in perfused hearts ex vivo. Moreover, liraglutide had no direct effect on sinoatrial node firing rate in mouse atrial preparations ex vivo. Despite co-localization of HCN4 and GLP-1R in primate hearts, HCN4-directed Cre expression did not attenuate levels of Glp1r mRNA transcripts, but did reduce atrial Gcgr expression in the mouse heart. GLP-1R agonists increase HR through multiple mechanisms, including regulation of autonomic nervous system function, and activation of the atrial GLP-1R. Surprisingly, the isolated atrial GLP-1R does not transduce a direct chronotropic effect following exposure to GLP-1R agonists in the intact heart, or isolated atrium, ex vivo. Hence, cardiac GLP-1R circuits controlling HR require neural inputs and do not function in a heart-autonomous manner. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

[Experimental infection of sheep with a rabies virus of canine origin: study of the pathogenicity for that species].

PubMed

Soria Baltazar, R; Artois, M; Blancou, J

1992-09-01

The effects of the inoculation of a canine strain of rabies virus in sheep were studied using ten animals which received different amounts of this virus. Two subjects, inoculated with 10(5.4) mouse intracerebral lethal doses 50% (MICLD50), died from rabies after 19 and 40 days of incubation. Clinical signs were anorexia, emaciation, nervous reactions and prostration before death. The virus was recovered from different parts of the central nervous system and salivary glands with high titres. Only three animals showed an antibody response, at very low levels.

Development and Function of the Mouse Vestibular System in the Absence of Gravity Perception

NASA Technical Reports Server (NTRS)

Wolgemuth, Debra J.

2005-01-01

The hypothesis that was tested in this research was that the absence of gravity perception, such as would occur in space, would affect the development and function of the vestibular and central nervous systems. Further, we postulated that these effects would be more significant at specific stages of post-natal development of the animal. We also proposed the use of molecular genetic approaches that would provide important information as to the hierarchy of gene function during the development and subsequent function of the vestibular system. The tilted (tlt) mutant mouse has been characterized as lacking the ability to provide sensory input to the gravity receptors. The tlt/tlt mutant mice were a particularly attractive model for the study of vestibular function since the primary defect was limited to the receptor part of the vestibular system, and there were no detectable abnormal phenotypes in other organ systems. The goal of the proposed studies was to assess immediate and delayed effects of the lack of gravity perception on the vestibular system. Particular attention was paid to characterizing primarily affected periods of vestibular morphogenesis, and to identifying downstream genetic pathways that are altered in the CNS of the tlt/tlt mutant mouse. The specific aims were: (1) to characterize the postnatal morphogenesis of the CNS in the tlt mutant mouse, using detailed morphometric analysis of isolated vestibular ganglia and brain tissue at different stages of postnatal development and assessment of apoptotic cell death; (2) to examine the expression of selected genes implicated by mutational analysis to be important in vestibular development or function by in situ hybridization or immunohistochemistry in the mutant mice; and (3) to identify other genes involved in vestibular development and function, using differential cloning strategies to isolate genes whose expression is changed in the mutant versus normal vestibular system.

Neonatal Ethanol Exposure Causes Behavioral Deficits in Young Mice.

PubMed

Xu, Wenhua; Hawkey, Andrew B; Li, Hui; Dai, Lu; Brim, Howard H; Frank, Jacqueline A; Luo, Jia; Barron, Susan; Chen, Gang

2018-04-01

Fetal ethanol (EtOH) exposure can damage the developing central nervous system and lead to cognitive and behavioral deficits, known as fetal alcohol spectrum disorders (FASD). EtOH exposure to mouse pups during early neonatal development was used as a model of EtOH exposure that overlaps the human third-trimester "brain growth spurt"-a model that has been widely used to study FASD in rats. C57BL/6 male and female mice were exposed to EtOH (4 g/kg/d) on postnatal days (PD) 4 to 10 by oral intubation. Intubated and nontreated controls were also included. Behavioral testing of the offspring, including open field, elevated plus maze, and Morris water maze, was performed on PD 20 to 45. EtOH exposure during PD 4 to 10 resulted in hyperactivity and deficits in learning and memory in young mice with no apparent sex differences. Based on these data, this neonatal intubation mouse model may be useful for future mechanistic and genetic studies of FASD and for screening of novel therapeutic agents. Copyright © 2018 by the Research Society on Alcoholism.

The novel KMO inhibitor CHDI-340246 leads to a restoration of electrophysiological alterations in mouse models of Huntington's disease.

PubMed

Beaumont, Vahri; Mrzljak, Ladislav; Dijkman, Ulrike; Freije, Robert; Heins, Mariette; Rassoulpour, Arash; Tombaugh, Geoffrey; Gelman, Simon; Bradaia, Amyaouch; Steidl, Esther; Gleyzes, Melanie; Heikkinen, Taneli; Lehtimäki, Kimmo; Puoliväli, Jukka; Kontkanen, Outi; Javier, Robyn M; Neagoe, Ioana; Deisemann, Heike; Winkler, Dirk; Ebneth, Andreas; Khetarpal, Vinod; Toledo-Sherman, Leticia; Dominguez, Celia; Park, Larry C; Munoz-Sanjuan, Ignacio

2016-08-01

Dysregulation of the kynurenine (Kyn) pathway has been associated with the progression of Huntington's disease (HD). In particular, elevated levels of the kynurenine metabolites 3-hydroxy kynurenine (3-OH-Kyn) and quinolinic acid (Quin), have been reported in the brains of HD patients as well as in rodent models of HD. The production of these metabolites is controlled by the activity of kynurenine mono-oxygenase (KMO), an enzyme which catalyzes the synthesis of 3-OH-Kyn from Kyn. In order to determine the role of KMO in the phenotype of mouse models of HD, we have developed a potent and selective KMO inhibitor termed CHDI-340246. We show that this compound, when administered orally to transgenic mouse models of HD, potently and dose-dependently modulates the Kyn pathway in peripheral tissues and in the central nervous system. The administration of CHDI-340246 leads to an inhibition of the formation of 3-OH-Kyn and Quin, and to an elevation of Kyn and Kynurenic acid (KynA) levels in brain tissues. We show that administration of CHDI-340246 or of Kyn and of KynA can restore several electrophysiological alterations in mouse models of HD, both acutely and after chronic administration. However, using a comprehensive panel of behavioral tests, we demonstrate that the chronic dosing of a selective KMO inhibitor does not significantly modify behavioral phenotypes or natural progression in mouse models of HD. Copyright © 2016. Published by Elsevier Inc.

Transgenic mice as an alternative to monkeys for neurovirulence testing of live oral poliovirus vaccine: validation by a WHO collaborative study.

PubMed Central

Dragunsky, Eugenia; Nomura, Tatsuji; Karpinski, Kazimir; Furesz, John; Wood, David J.; Pervikov, Yuri; Abe, Shinobu; Kurata, Takeshi; Vanloocke, Olivier; Karganova, Galina; Taffs, Rolf; Heath, Alan; Ivshina, Anna; Levenbook, Inessa

2003-01-01

OBJECTIVE: Extensive WHO collaborative studies were performed to evaluate the suitability of transgenic mice susceptible to poliovirus (TgPVR mice, strain 21, bred and provided by the Central Institute for Experimental Animals, Japan) as an alternative to monkeys in the neurovirulence test (NVT) of oral poliovirus vaccine (OPV). METHODS: Nine laboratories participated in the collaborative study on testing neurovirulence of 94 preparations of OPV and vaccine derivatives of all three serotypes in TgPVR21 mice. FINDINGS: Statistical analysis of the data demonstrated that the TgPVR21 mouse NVT was of comparable sensitivity and reproducibility to the conventional WHO NVT in simians. A statistical model for acceptance/rejection of OPV lots in the mouse test was developed, validated, and shown to be suitable for all three vaccine types. The assessment of the transgenic mouse NVT is based on clinical evaluation of paralysed mice. Unlike the monkey NVT, histological examination of central nervous system tissue of each mouse offered no advantage over careful and detailed clinical observation. CONCLUSIONS: Based on data from the collaborative studies the WHO Expert Committee for Biological Standardization approved the mouse NVT as an alternative to the monkey test for all three OPV types and defined a standard implementation process for laboratories that wish to use the test. This represents the first successful introduction of transgenic animals into control of biologicals. PMID:12764491

Functional Role of the Disulfide Isomerase ERp57 in Axonal Regeneration.

PubMed

Castillo, Valentina; Oñate, Maritza; Woehlbier, Ute; Rozas, Pablo; Andreu, Catherine; Medinas, Danilo; Valdés, Pamela; Osorio, Fabiola; Mercado, Gabriela; Vidal, René L; Kerr, Bredford; Court, Felipe A; Hetz, Claudio

2015-01-01

ERp57 (also known as grp58 and PDIA3) is a protein disulfide isomerase that catalyzes disulfide bonds formation of glycoproteins as part of the calnexin and calreticulin cycle. ERp57 is markedly upregulated in most common neurodegenerative diseases downstream of the endoplasmic reticulum (ER) stress response. Despite accumulating correlative evidence supporting a neuroprotective role of ERp57, the contribution of this foldase to the physiology of the nervous system remains unknown. Here we developed a transgenic mouse model that overexpresses ERp57 in the nervous system under the control of the prion promoter. We analyzed the susceptibility of ERp57 transgenic mice to undergo neurodegeneration. Unexpectedly, ERp57 overexpression did not affect dopaminergic neuron loss and striatal denervation after injection of a Parkinson's disease-inducing neurotoxin. In sharp contrast, ERp57 transgenic animals presented enhanced locomotor recovery after mechanical injury to the sciatic nerve. These protective effects were associated with enhanced myelin removal, macrophage infiltration and axonal regeneration. Our results suggest that ERp57 specifically contributes to peripheral nerve regeneration, whereas its activity is dispensable for the survival of a specific neuronal population of the central nervous system. These results demonstrate for the first time a functional role of a component of the ER proteostasis network in peripheral nerve regeneration.

Oculomotor Deficits in Aryl Hydrocarbon Receptor Null Mouse

PubMed Central

Chevallier, Aline; Mialot, Antoine; Petit, Jean-Maurice; Fernandez-Salguero, Pedro; Barouki, Robert

2013-01-01

The Aryl hydrocarbon Receptor or AhR, a ligand-activated transcription factor, is known to mediate the toxic and carcinogenic effects of various environmental pollutants such as 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD). Recent studies in Caenorhabditis elegans and Drosophila melanogaster show that the orthologs of the AhR are expressed exclusively in certain types of neurons and are implicated in the development and the homeostasis of the central nervous system. While physiological roles of the AhR were demonstrated in the mammalian heart, liver and gametogenesis, its ontogenic expression and putative neural functions remain elusive. Here, we report that the constitutive absence of the AhR in adult mice (AhR−/−) leads to abnormal eye movements in the form of a spontaneous pendular horizontal nystagmus. To determine if the nystagmus is of vestibular, visual, or cerebellar origin, gaze stabilizing reflexes, namely vestibulo-ocular and optokinetic reflexes (VOR and OKR), were investigated. The OKR is less effective in the AhR−/− mice suggesting a deficit in the visuo-motor circuitry, while the VOR is mildly affected. Furthermore, the AhR is expressedin the retinal ganglion cells during the development, however electroretinograms revealed no impairment of retinal cell function. The structure of the cerebellum of the AhR−/− mice is normal which is compatible with the preserved VOR adaptation, a plastic process dependent on cerebellar integrity. Finally, intoxication with TCDD of control adults did not lead to any abnormality of the oculomotor control. These results demonstrate that the absence of the AhR leads to acquired central nervous system deficits in the adults. Given the many common features between both AhR mouse and human infantile nystagmus syndromes, the AhR−/− mice might give insights into the developmental mechanisms which lead to congenital eye disorders. PMID:23301081

Hippocampal TNFα Signaling Contributes to Seizure Generation in an Infection-Induced Mouse Model of Limbic Epilepsy.

PubMed

Patel, Dipan C; Wallis, Glenna; Dahle, E Jill; McElroy, Pallavi B; Thomson, Kyle E; Tesi, Raymond J; Szymkowski, David E; West, Peter J; Smeal, Roy M; Patel, Manisha; Fujinami, Robert S; White, H Steve; Wilcox, Karen S

2017-01-01

Central nervous system infection can induce epilepsy that is often refractory to established antiseizure drugs. Previous studies in the Theiler's murine encephalomyelitis virus (TMEV)-induced mouse model of limbic epilepsy have demonstrated the importance of inflammation, especially that mediated by tumor necrosis factor-α (TNFα), in the development of acute seizures. TNFα modulates glutamate receptor trafficking via TNF receptor 1 (TNFR1) to cause increased excitatory synaptic transmission. Therefore, we hypothesized that an increase in TNFα signaling after TMEV infection might contribute to acute seizures. We found a significant increase in both mRNA and protein levels of TNFα and the protein expression ratio of TNF receptors (TNFR1:TNFR2) in the hippocampus, a brain region most likely involved in seizure initiation, after TMEV infection, which suggests that TNFα signaling, predominantly through TNFR1, may contribute to limbic hyperexcitability. An increase in hippocampal cell-surface glutamate receptor expression was also observed during acute seizures. Although pharmacological inhibition of TNFR1-mediated signaling had no effect on acute seizures, several lines of genetically modified animals deficient in either TNFα or TNFRs had robust changes in seizure incidence and severity after TMEV infection. TNFR2 -/- mice were highly susceptible to developing acute seizures, suggesting that TNFR2-mediated signaling may provide beneficial effects during the acute seizure period. Taken together, the present results suggest that inflammation in the hippocampus, caused predominantly by TNFα signaling, contributes to hyperexcitability and acute seizures after TMEV infection. Pharmacotherapies designed to suppress TNFR1-mediated or augment TNFR2-mediated effects of TNFα may provide antiseizure and disease-modifying effects after central nervous system infection.

Cis-regulatory underpinnings of human GLI3 expression in embryonic craniofacial structures and internal organs.

PubMed

Abbasi, Amir A; Minhas, Rashid; Schmidt, Ansgar; Koch, Sabine; Grzeschik, Karl-Heinz

2013-10-01

The zinc finger transcription factor Gli3 is an important mediator of Sonic hedgehog (Shh) signaling. During early embryonic development Gli3 participates in patterning and growth of the central nervous system, face, skeleton, limb, tooth and gut. Precise regulation of the temporal and spatial expression of Gli3 is crucial for the proper specification of these structures in mammals and other vertebrates. Previously we reported a set of human intronic cis-regulators controlling almost the entire known repertoire of endogenous Gli3 expression in mouse neural tube and limbs. However, the genetic underpinning of GLI3 expression in other embryonic domains such as craniofacial structures and internal organs remain elusive. Here we demonstrate in a transgenic mice assay the potential of a subset of human/fish conserved non-coding sequences (CNEs) residing within GLI3 intronic intervals to induce reporter gene expression at known regions of endogenous Gli3 transcription in embryonic domains other than central nervous system (CNS) and limbs. Highly specific reporter expression was observed in craniofacial structures, eye, gut, and genitourinary system. Moreover, the comparison of expression patterns directed by these intronic cis-acting regulatory elements in mouse and zebrafish embryos suggests that in accordance with sequence conservation, the target site specificity of a subset of these elements remains preserved among these two lineages. Taken together with our recent investigations, it is proposed here that during vertebrate evolution the Gli3 expression control acquired multiple, independently acting, intronic enhancers for spatiotemporal patterning of CNS, limbs, craniofacial structures and internal organs. © 2013 The Authors Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.

Hippocampal TNFα Signaling Contributes to Seizure Generation in an Infection-Induced Mouse Model of Limbic Epilepsy

PubMed Central

Patel, Dipan C.; Wallis, Glenna; Dahle, E. Jill; McElroy, Pallavi B.; Thomson, Kyle E.; West, Peter J.; Smeal, Roy M.; Patel, Manisha; Fujinami, Robert S.; White, H. Steve

2017-01-01

Abstract Central nervous system infection can induce epilepsy that is often refractory to established antiseizure drugs. Previous studies in the Theiler’s murine encephalomyelitis virus (TMEV)-induced mouse model of limbic epilepsy have demonstrated the importance of inflammation, especially that mediated by tumor necrosis factor-α (TNFα), in the development of acute seizures. TNFα modulates glutamate receptor trafficking via TNF receptor 1 (TNFR1) to cause increased excitatory synaptic transmission. Therefore, we hypothesized that an increase in TNFα signaling after TMEV infection might contribute to acute seizures. We found a significant increase in both mRNA and protein levels of TNFα and the protein expression ratio of TNF receptors (TNFR1:TNFR2) in the hippocampus, a brain region most likely involved in seizure initiation, after TMEV infection, which suggests that TNFα signaling, predominantly through TNFR1, may contribute to limbic hyperexcitability. An increase in hippocampal cell-surface glutamate receptor expression was also observed during acute seizures. Although pharmacological inhibition of TNFR1-mediated signaling had no effect on acute seizures, several lines of genetically modified animals deficient in either TNFα or TNFRs had robust changes in seizure incidence and severity after TMEV infection. TNFR2–/– mice were highly susceptible to developing acute seizures, suggesting that TNFR2-mediated signaling may provide beneficial effects during the acute seizure period. Taken together, the present results suggest that inflammation in the hippocampus, caused predominantly by TNFα signaling, contributes to hyperexcitability and acute seizures after TMEV infection. Pharmacotherapies designed to suppress TNFR1-mediated or augment TNFR2-mediated effects of TNFα may provide antiseizure and disease-modifying effects after central nervous system infection. PMID:28497109

HERC1 Ubiquitin Ligase Is Required for Normal Axonal Myelination in the Peripheral Nervous System.

PubMed

Bachiller, Sara; Roca-Ceballos, María Angustias; García-Domínguez, Irene; Pérez-Villegas, Eva María; Martos-Carmona, David; Pérez-Castro, Miguel Ángel; Real, Luis Miguel; Rosa, José Luis; Tabares, Lucía; Venero, José Luis; Armengol, José Ángel; Carrión, Ángel Manuel; Ruiz, Rocío

2018-03-30

A missense mutation in HERC1 provokes loss of cerebellar Purkinje cells, tremor, and unstable gait in tambaleante (tbl) mice. Recently, we have shown that before cerebellar degeneration takes place, the tbl mouse suffers from a reduction in the number of vesicles available for release at the neuromuscular junction (NMJ). The aim of the present work was to study to which extent the alteration in HERC1 may affect other cells in the nervous system and how this may influence the motor dysfunction observed in these mice. The functional analysis showed a consistent delay in the propagation of the action potential in mutant mice in comparison with control littermates. Morphological analyses of glial cells in motor axons revealed signs of compact myelin damage as tomacula and local hypermyelination foci. Moreover, we observed an alteration in non-myelinated terminal Schwann cells at the level of the NMJ. Additionally, we found a significant increment of phosphorylated Akt-2 in the sciatic nerve. Based on these findings, we propose a molecular model that could explain how mutated HERC1 in tbl mice affects the myelination process in the peripheral nervous system. Finally, since the myelin abnormalities found in tbl mice are histological hallmarks of neuropathic periphery diseases, tbl mutant mice could be considered as a new mouse model for this type of diseases.

Synaptic inhibition and γ-aminobutyric acid in the mammalian central nervous system

PubMed Central

OBATA, Kunihiko

2013-01-01

Signal transmission through synapses connecting two neurons is mediated by release of neurotransmitter from the presynaptic axon terminals and activation of its receptor at the postsynaptic neurons. γ-Aminobutyric acid (GABA), non-protein amino acid formed by decarboxylation of glutamic acid, is a principal neurotransmitter at inhibitory synapses of vertebrate and invertebrate nervous system. On one hand glutamic acid serves as a principal excitatory neurotransmitter. This article reviews GABA researches on; (1) synaptic inhibition by membrane hyperpolarization, (2) exclusive localization in inhibitory neurons, (3) release from inhibitory neurons, (4) excitatory action at developmental stage, (5) phenotype of GABA-deficient mouse produced by gene-targeting, (6) developmental adjustment of neural network and (7) neurological/psychiatric disorder. In the end, GABA functions in simple nervous system and plants, and non-amino acid neurotransmitters were supplemented. PMID:23574805

ANTIRABIES ANTIBODY RESPONSE IN MAN TO VACCINE MADE FROM INFECTED SUCKLING-MOUSE BRAINS.

PubMed

FUENZALIDA, E; PALACIOS, R; BORGONO, J M

1964-01-01

Antirabies vaccines produced from infected brains of adult mammals have always had the potentiality of causing post-vaccinal paralysis or allergic encephalitis in man. Attempts in recent years either to remove the paralytic factor from brain-tissue vaccines or to use as the virus source infected tissue other than nervous tissue (e.g., chick embryos) have usually resulted in a substantial reduction of the specific antirabies potency.The authors' laboratory had previously developed a vaccine made from infected suckling-mouse brains in which the virus was inactivated by ultraviolet irradiation. This vaccine was found highly potent in animal tests and low in organ-specific antigens. Others have found the brains of newborn mammals to be free of the allergic encephalitic factor. The studies reported in this paper show that the antirabies antibody responses to a 14-dose course of this suckling-mouse-brain vaccine in children are at a high level even when the vaccine is used at a 1% tissue concentration. There was no evidence of deleterious reactions to this treatment in 31 children.It is concluded that these results justify a long-term trial of this vaccine for antirabies prophylaxis in man.

Antirabies antibody response in man to vaccine made from infected suckling-mouse brains

PubMed Central

Fuenzalida, E.; Palacios, R.; Borgoño, J. M.

1964-01-01

Antirabies vaccines produced from infected brains of adult mammals have always had the potentiality of causing post-vaccinal paralysis or allergic encephalitis in man. Attempts in recent years either to remove the paralytic factor from brain-tissue vaccines or to use as the virus source infected tissue other than nervous tissue (e.g., chick embryos) have usually resulted in a substantial reduction of the specific antirabies potency. The authors' laboratory had previously developed a vaccine made from infected suckling-mouse brains in which the virus was inactivated by ultraviolet irradiation. This vaccine was found highly potent in animal tests and low in organ-specific antigens. Others have found the brains of newborn mammals to be free of the allergic encephalitic factor. The studies reported in this paper show that the antirabies antibody responses to a 14-dose course of this suckling-mouse-brain vaccine in children are at a high level even when the vaccine is used at a 1% tissue concentration. There was no evidence of deleterious reactions to this treatment in 31 children. It is concluded that these results justify a long-term trial of this vaccine for antirabies prophylaxis in man. PMID:14163964

Comprehensive optical and data management infrastructure for high-throughput light-sheet microscopy of whole mouse brains.

PubMed

Müllenbroich, M Caroline; Silvestri, Ludovico; Onofri, Leonardo; Costantini, Irene; Hoff, Marcel Van't; Sacconi, Leonardo; Iannello, Giulio; Pavone, Francesco S

2015-10-01

Comprehensive mapping and quantification of neuronal projections in the central nervous system requires high-throughput imaging of large volumes with microscopic resolution. To this end, we have developed a confocal light-sheet microscope that has been optimized for three-dimensional (3-D) imaging of structurally intact clarified whole-mount mouse brains. We describe the optical and electromechanical arrangement of the microscope and give details on the organization of the microscope management software. The software orchestrates all components of the microscope, coordinates critical timing and synchronization, and has been written in a versatile and modular structure using the LabVIEW language. It can easily be adapted and integrated to other microscope systems and has been made freely available to the light-sheet community. The tremendous amount of data routinely generated by light-sheet microscopy further requires novel strategies for data handling and storage. To complete the full imaging pipeline of our high-throughput microscope, we further elaborate on big data management from streaming of raw images up to stitching of 3-D datasets. The mesoscale neuroanatomy imaged at micron-scale resolution in those datasets allows characterization and quantification of neuronal projections in unsectioned mouse brains.

TRPA1 deficiency is protective in cuprizone-induced demyelination-A new target against oligodendrocyte apoptosis.

PubMed

Sághy, Éva; Sipos, Éva; Ács, Péter; Bölcskei, Kata; Pohóczky, Krisztina; Kemény, Ágnes; Sándor, Zoltán; Szőke, Éva; Sétáló, György; Komoly, Sámuel; Pintér, Erika

2016-12-01

Multiple sclerosis is a chronic inflammatory, demyelinating degenerative disease of the central nervous system. Current treatments target pathological immune responses to counteract the inflammatory processes. However, these drugs do not restrain the long-term progression of clinical disability. For this reason, new therapeutic approaches and identification of novel target molecules are needed to prevent demyelination or promote repair mechanisms. Transient Receptor Potential Ankyrin 1 (TRPA1) is a nonselective cation channel with relatively high Ca 2+ permeability. Its pathophysiological role in central nervous system disorders has not been elucidated yet. In the present study, we aimed to assess the distribution of TRPA1 in the mouse brain and reveal its regulatory role in the cuprizone-induced demyelination. This toxin-induced model, characterized by oligodendrocyte apoptosis and subsequent primary demyelination, allows us to investigate the nonimmune aspects of multiple sclerosis. We found that TRPA1 is expressed on astrocytes in the mouse central nervous system. Interestingly, TRPA1 deficiency significantly attenuated cuprizone-induced demyelination by reducing the apoptosis of mature oligodendrocytes. Our data suggest that TRPA1 regulates mitogen-activated protein kinase pathways, as well as transcription factor c-Jun and a proapoptotic Bcl-2 family member (Bak) expression resulting in enhanced oligodendrocyte apoptosis. In conclusion, we propose that TRPA1 receptors enhancing the intracellular Ca 2+ concentration modulate astrocyte functions, and influence the pro or anti-apoptotic pathways in oligodendrocytes. Inhibition of TRPA1 receptors might successfully diminish the degenerative pathology in multiple sclerosis and could be a promising therapeutic target to limit central nervous system damage in demyelinating diseases. GLIA 2016;64:2166-2180. © 2016 Wiley Periodicals, Inc.

NBQX, a highly selective competitive antagonist of AMPA and KA ionotropic glutamate receptors, increases seizures and mortality following picornavirus infection

PubMed Central

Libbey, Jane E.; Hanak, Tyler J.; Doty, Daniel J.; Wilcox, Karen S.; Fujinami, Robert S.

2016-01-01

Seizures occur due to an imbalance between excitation and inhibition, with the balance tipping towards excitation, and glutamate is the predominant excitatory neurotransmitter in the central nervous system of mammals. Since upregulation of expression and/or function of glutamate receptors can contribute to seizures we determined the effects of three antagonists, NBQX, GYKI-52466 and MK 801, of the various ionotropic glutamate receptors, AMPA, NMDA and KA, on acute seizure development in the Theiler’s murine encephalomyelitis virus (TMEV)-induced seizure model. We found that only NBQX had an effect on acute seizure development, resulting in a significantly higher number of mice experiencing seizures, an increase in the number of seizures per mouse, a greater cumulative seizure score per mouse and a significantly higher mortality rate among the mice. Although NBQX has previously been shown to be a potent anticonvulsant in animal seizure models, seizures induced by electrical stimulation, drug administration or as a result of genetic predisposition may differ greatly in terms of mechanism of seizure development from our virus-induced seizure model, which could explain the opposite, proconvulsant effect of NBQX observed in the TMEV-induced seizure model. PMID:27072529

Discovery of Transcription Factors Novel to Mouse Cerebellar Granule Cell Development Through Laser-Capture Microdissection.

PubMed

Zhang, Peter G Y; Yeung, Joanna; Gupta, Ishita; Ramirez, Miguel; Ha, Thomas; Swanson, Douglas J; Nagao-Sato, Sayaka; Itoh, Masayoshi; Kawaji, Hideya; Lassmann, Timo; Daub, Carsten O; Arner, Erik; de Hoon, Michiel; Carninci, Piero; Forrest, Alistair R R; Hayashizaki, Yoshihide; Goldowitz, Dan

2018-06-01

Laser-capture microdissection was used to isolate external germinal layer tissue from three developmental periods of mouse cerebellar development: embryonic days 13, 15, and 18. The cerebellar granule cell-enriched mRNA library was generated with next-generation sequencing using the Helicos technology. Our objective was to discover transcriptional regulators that could be important for the development of cerebellar granule cells-the most numerous neuron in the central nervous system. Through differential expression analysis, we have identified 82 differentially expressed transcription factors (TFs) from a total of 1311 differentially expressed genes. In addition, with TF-binding sequence analysis, we have identified 46 TF candidates that could be key regulators responsible for the variation in the granule cell transcriptome between developmental stages. Altogether, we identified 125 potential TFs (82 from differential expression analysis, 46 from motif analysis with 3 overlaps in the two sets). From this gene set, 37 TFs are considered novel due to the lack of previous knowledge about their roles in cerebellar development. The results from transcriptome-wide analyses were validated with existing online databases, qRT-PCR, and in situ hybridization. This study provides an initial insight into the TFs of cerebellar granule cells that might be important for development and provide valuable information for further functional studies on these transcriptional regulators.

A New Model for Hendra Virus Encephalitis in the Mouse

PubMed Central

Dups, Johanna; Middleton, Deborah; Yamada, Manabu; Monaghan, Paul; Long, Fenella; Robinson, Rachel; Marsh, Glenn A.; Wang, Lin-Fa

2012-01-01

Hendra virus (HeV) infection in humans is characterized by an influenza like illness, which may progress to pneumonia or encephalitis and lead to death. The pathogenesis of HeV infection is poorly understood, and the lack of a mouse model has limited the opportunities for pathogenetic research. In this project we reassessed the role of mice as an animal model for HeV infection and found that mice are susceptible to HeV infection after intranasal exposure, with aged mice reliably developing encephalitic disease. We propose an anterograde route of neuroinvasion to the brain, possibly along olfactory nerves. This is supported by evidence for the development of encephalitis in the absence of viremia and the sequential distribution of viral antigen along pathways of olfaction in the brain of intranasally challenged animals. In our studies mice developed transient lower respiratory tract infection without progressing to viremia and systemic vasculitis that is common to other animal models. These studies report a new animal model of HeV encephalitis that will allow more detailed studies of the neuropathogenesis of HeV infection, particularly the mode of viral spread and possible sequestration within the central nervous system; investigation of mechanisms that moderate the development of viremia and systemic disease; and inform the development of improved treatment options for human patients. PMID:22808132

Correlation of Versican Expression, Accumulation, and Degradation during Embryonic Development by Quantitative Immunohistochemistry

PubMed Central

Snyder, Jessica M.; Washington, Ida M.; Birkland, Timothy; Chang, Mary Y.; Frevert, Charles W.

2015-01-01

Versican, a chondroitin sulfate proteoglycan, is important in embryonic development, and disruption of the versican gene is embryonically lethal in the mouse. Although several studies show that versican is increased in various organs during development, a focused quantitative study on versican expression and distribution during lung and central nervous system development in the mouse has not previously been performed. We tracked changes in versican (Vcan) gene expression and in the accumulation and degradation of versican. Vcan expression and quantitative immunohistochemistry performed from embryonic day (E) 11.5 to E15.5 showed peak Vcan expression at E13.5 in the lungs and brain. Quantitative mRNA analysis and versican immunohistochemistry showed differences in the expression of the versican isoforms in the embryonic lung and head. The expression of Vcan mRNA and accumulation of versican in tissues was complementary. Immunohistochemistry demonstrated co-localization of versican accumulation and degradation, suggesting distinct roles of versican deposition and degradation in embryogenesis. Very little versican mRNA or protein was found in the lungs of 12- to 16-week-old mice but versican accumulation was significantly increased in mice with Pseudomonas aeruginosa lung infection. These data suggest that versican plays an important role in fundamental, overlapping cellular processes in lung development and infection. PMID:26385570

Development and validation of LC-MS/MS method for quantitative determination of (-)-securinine in mouse plasma.

PubMed

Wabuyele, Simuli L; Wald, David; Xu, Yan

2014-06-01

(-)-Securinine (SE) is a major alkaloid found in plant Securinega suffruticosa, which has a wide range of pharmacological activities including anticancer, anti-parasitic and central nervous system stimulating effects, etc. To aid the pharmacological study of SE, we developed an LC-MS/MS method for quantitative determination of SE in mouse plasma. In this method, plasma samples were first prepared with salting-out assisted liquid-liquid extraction using cold acetonitrile (-20°C) and 2.00 M ammonium acetate. Separation of SE and the internal standard (IS) from sample matrix was achieved on a Gemini Nx C18 column using 40% acetonitrile and 60% 10.0mM ammonium acetate at a flow rate of 0.200 mL min(-1). Quantification of SE was accomplished with positive electrospray ionization tandem mass spectrometry using mass transitions m/z 218.1→84.1 for SE, and m/z 204.1→70.2 for the IS. This method has a lower limit of quantitation (LLOQ) of 0.600 ng mL(-1) and a linear calibration range up to 600 ng mL(-1) in mouse plasma. The intra- and inter-run accuracy (%RE) and precision (%CV) were ≤ ± 6% and 6%, respectively. The IS normalized matrix factors from six lots of plasma matrices ranged 0.92-1.07, and the recoveries of plasma SE were 99-109%. The validated method has been applied to the measurement of SE in plasma samples of a mouse study. Copyright © 2014 Elsevier B.V. All rights reserved.

Glucosylceramide Administration as a Vaccination Strategy in Mouse Models of Cryptococcosis.

PubMed

Mor, Visesato; Farnoud, Amir M; Singh, Ashutosh; Rella, Antonella; Tanno, Hiromasa; Ishii, Keiko; Kawakami, Kazuyoshi; Sato, Toshiya; Del Poeta, Maurizio

2016-01-01

Cryptococcus neoformans is an opportunistic fungal pathogen and the causative agent of the disease cryptococcosis. Cryptococcosis is initiated as a pulmonary infection and in conditions of immune deficiency disseminates to the blood stream and central nervous system, resulting in life-threatening meningoencephalitis. A number of studies have focused on the development of a vaccine against Cryptococcus, primarily utilizing protein-conjugated components of the Cryptococcus polysaccharide capsule as antigen. However, there is currently no vaccine against Cryptococcus in the clinic. Previous studies have shown that the glycosphingolipid, glucosylceramide (GlcCer), is a virulence factor in C. neoformans and antibodies against this lipid inhibit fungal growth and cell division. In the present study, we have investigated the possibility of using GlcCer as a therapeutic agent against C. neoformans infections in mouse models of cryptococcosis. GlcCer purified from a non-pathogenic fungus, Candida utilis, was administered intraperitoneally, prior to infecting mice with a lethal dose of C. neoformans. GlcCer administration prevented the dissemination of C. neoformans from the lungs to the brain and led to 60% mouse survival. GlcCer administration did not cause hepatic injury and elicited an anti-GlcCer antibody response, which was observed independent of the route of administration and the strains of mouse. Taken together, our results suggest that fungal GlcCer can protect mice against lethal doses of C. neoformans infection and can provide a viable vaccination strategy against Cryptococcus.

Characterization of pancreatic glucagon-producing tumors and pituitary gland tumors in transgenic mice overexpressing MYCN in hGFAP-positive cells.

PubMed

Fielitz, Kathrin; Althoff, Kristina; De Preter, Katleen; Nonnekens, Julie; Ohli, Jasmin; Elges, Sandra; Hartmann, Wolfgang; Klöppel, Günter; Knösel, Thomas; Schulte, Marc; Klein-Hitpass, Ludger; Beisser, Daniela; Reis, Henning; Eyking, Annette; Cario, Elke; Schulte, Johannes H; Schramm, Alexander; Schüller, Ulrich

2016-11-15

Amplification or overexpression of MYCN is involved in development and maintenance of multiple malignancies. A subset of these tumors originates from neural precursors, including the most aggressive forms of the childhood tumors, neuroblastoma and medulloblastoma. In order to model the spectrum of MYCN-driven neoplasms in mice, we transgenically overexpressed MYCN under the control of the human GFAP-promoter that, among other targets, drives expression in neural progenitor cells. However, LSL-MYCN;hGFAP-Cre double transgenic mice did neither develop neural crest tumors nor tumors of the central nervous system, but presented with neuroendocrine tumors of the pancreas and, less frequently, the pituitary gland. Pituitary tumors expressed chromogranin A and closely resembled human pituitary adenomas. Pancreatic tumors strongly produced and secreted glucagon, suggesting that they derived from glucagon- and GFAP-positive islet cells. Interestingly, 3 out of 9 human pancreatic neuroendocrine tumors expressed MYCN, supporting the similarity of the mouse tumors to the human system. Serial transplantations of mouse tumor cells into immunocompromised mice confirmed their fully transformed phenotype. MYCN-directed treatment by AuroraA- or Brd4-inhibitors resulted in significantly decreased cell proliferation in vitro and reduced tumor growth in vivo. In summary, we provide a novel mouse model for neuroendocrine tumors of the pancreas and pituitary gland that is dependent on MYCN expression and that may help to evaluate MYCN-directed therapies.

Loss of aPKCλ in Differentiated Neurons Disrupts the Polarity Complex but Does Not Induce Obvious Neuronal Loss or Disorientation in Mouse Brains

PubMed Central

Yamanaka, Tomoyuki; Tosaki, Asako; Kurosawa, Masaru; Akimoto, Kazunori; Hirose, Tomonori; Ohno, Shigeo; Hattori, Nobutaka; Nukina, Nobuyuki

2013-01-01

Cell polarity plays a critical role in neuronal differentiation during development of the central nervous system (CNS). Recent studies have established the significance of atypical protein kinase C (aPKC) and its interacting partners, which include PAR-3, PAR-6 and Lgl, in regulating cell polarization during neuronal differentiation. However, their roles in neuronal maintenance after CNS development remain unclear. Here we performed conditional deletion of aPKCλ, a major aPKC isoform in the brain, in differentiated neurons of mice by camk2a-cre or synapsinI-cre mediated gene targeting. We found significant reduction of aPKCλ and total aPKCs in the adult mouse brains. The aPKCλ deletion also reduced PAR-6β, possibly by its destabilization, whereas expression of other related proteins such as PAR-3 and Lgl-1 was unaffected. Biochemical analyses suggested that a significant fraction of aPKCλ formed a protein complex with PAR-6β and Lgl-1 in the brain lysates, which was disrupted by the aPKCλ deletion. Notably, the aPKCλ deletion mice did not show apparent cell loss/degeneration in the brain. In addition, neuronal orientation/distribution seemed to be unaffected. Thus, despite the polarity complex disruption, neuronal deletion of aPKCλ does not induce obvious cell loss or disorientation in mouse brains after cell differentiation. PMID:24391875

Quantitative assessment of the blood-brain barrier opening caused by Streptococcus agalactiae hyaluronidase in a BALB/c mouse model.

PubMed

Luo, Su; Cao, Qing; Ma, Ke; Wang, Zhaofei; Liu, Guangjin; Lu, Chengping; Liu, Yongjie

2017-10-19

Streptococcus agalactiae is a pathogen causing meningitis in animals and humans. However, little is known about the entry of S. agalactiae into brain tissue. In this study, we developed a BALB/c mouse model based on the intravenous injection of β-galactosidase-positive Escherichia coli M5 as an indicator of blood-brain barrier (BBB) opening. Under physiological conditions, the BBB is impermeable to E. coli M5. In pathological conditions caused by S. agalactiae, E. coli M5 is capable of penetrating the brain through a disrupted BBB. The level of BBB opening can be assessed by quantitative measurement of E. coli M5 loads per gram of brain tissue. Further, we used the model to evaluate the role of S. agalactiae hyaluronidase in BBB opening. The inactivation of hylB gene encoding a hyaluronidase, HylB, resulted in significantly decreased E. coli M5 colonization, and the intravenous injection of purified HylB protein induced BBB opening in a dose-dependent manner. This finding verified the direct role of HylB in BBB invasion and traversal, and further demonstrated the practicability of the in vivo mouse model established in this study. This model will help to understand the S. agalactiae-host interactions that are involved in this bacterial traversal of the BBB and to develop efficacious strategies to prevent central nervous system infections.

The cytokine macrophage migration inhibitory factor (MIF) acts as a neurotrophin in the developing inner ear of the zebrafish, Danio rerio

PubMed Central

Shen, Yu-chi; Thompson, Deborah L.; Kuah, Meng-Kiat; Wong, Kah-Loon; Wu, Karen L.; Linn, Stephanie A.; Jewett, Ethan M.; Shu-Chien, Alexander Chong; Barald, Kate F.

2012-01-01

Macrophage migration inhibitory factor (MIF) plays versatile roles in the immune system. MIF is also widely expressed during embryonic development, particularly in the nervous system, although its roles in neural development are only beginning to be understood. Evidence from frogs, mice and zebrafish suggests that MIF has a major role as a neurotrophin in the early development of sensory systems, including the auditory system. Here we show that the zebrafish mif pathway is required for both sensory hair cell (HC) and sensory neuronal cell survival in the ear, for HC differentiation, semicircular canal formation, statoacoustic ganglion (SAG) development, and lateral line HC differentiation. This is consistent with our findings that MIF is expressed in the developing mammalian and avian auditory systems and promotes mouse and chick SAG neurite outgrowth and neuronal survival, demonstrating key instructional roles for MIF in vertebrate otic development. PMID:22210003

Peripheral denervation participates in heterotopic ossification in a spinal cord injury model

PubMed Central

Salga, Marjorie; Begot, Laurent; Holy, Xavier; Chedik, Malha; de l’Escalopier, Nicolas; Torossian, Fréderic; Levesque, Jean-Pierre; Lataillade, Jean-Jacques; Le Bousse-Kerdilès, Marie-Caroline; Genêt, François

2017-01-01

We previously reported the development of a new acquired neurogenic HO (NHO) mouse model, combining spinal cord transection (SCI) and chemical muscle injury. Pathological mechanisms responsible for ectopic osteogenesis after central neurological damage are still to be elucidated. In this study, we first hypothesized that peripheral nervous system (PNS) might convey pathological signals from injured spinal cord to muscles in NHO mouse model. Secondly, we sought to determine whether SCI could lead to intramuscular modifications of BMP2 signaling pathways. Twenty one C57Bl6 mice were included in this protocol. Bilateral cardiotoxin (CTX) injection in hamstring muscles was associated with a two-stage surgical procedure, combining thoracic SCI with unilateral peripheral denervation. Volumes of HO (Bone Volume, BV) were measured 28 days after surgery using micro-computed tomography imaging techniques and histological analyses were made to confirm intramuscular osteogenesis. Volume comparisons were conducted between right and left hind limb of each animal, using a Wilcoxon signed rank test. Quantitative polymerase chain reaction (qPCR) was performed to explore intra muscular expression of BMP2, Alk3 and Id1. Nineteen mice survive the complete SCI and peripheral denervation procedure. When CTX injections were done right after surgery (n = 7), bilateral HO were detected in all animals after 28 days. Micro-CT measurements showed significantly increased BV in denervated paws (1.47 mm3 +/- 0.5) compared to contralateral sides (0.56 mm3 +/-0.4), p = 0.03. When peripheral denervation and CTX injections were performed after sham SCI surgery (n = 6), bilateral HO were present in three mice at day 28. Quantitative PCR analyses showed no changes in intra muscular BMP2 expression after SCI as compared to control mice (shamSCI). Peripheral denervation can be reliably added to spinal cord transection in NHO mouse model. This new experimental design confirms that neuro inflammatory mechanisms induced by central or peripheral nervous system injury plays a key role in triggering ectopic osteogenesis. PMID:28854256

Lithium treatment elongates primary cilia in the mouse brain and in cultured cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyoshi, Ko, E-mail: miyoshi@cc.okayama-u.ac.jp; Kasahara, Kyosuke; Miyazaki, Ikuko

2009-10-30

The molecular mechanisms underlying the therapeutic effects of lithium, a first-line antimanic mood stabilizer, have not yet been fully elucidated. Treatment of the algae Chlamydomonas reinhardtii with lithium has been shown to induce elongation of their flagella, which are analogous structures to vertebrate cilia. In the mouse brain, adenylyl cyclase 3 (AC3) and certain neuropeptide receptors colocalize to the primary cilium of neuronal cells, suggesting a chemosensory function for the primary cilium in the nervous system. Here we show that lithium treatment elongates primary cilia in the mouse brain and in cultured cells. Brain sections from mice chronically fed withmore » Li{sub 2}CO{sub 3} were subjected to immunofluorescence study. Primary cilia carrying both AC3 and the receptor for melanin-concentrating hormone (MCH) were elongated in the dorsal striatum and nucleus accumbens of lithium-fed mice, as compared to those of control animals. Moreover, lithium-treated NIH3T3 cells and cultured striatal neurons exhibited elongation of the primary cilia. The present results provide initial evidence that a psychotropic agent can affect ciliary length in the central nervous system, and furthermore suggest that lithium exerts its therapeutic effects via the upregulation of cilia-mediated MCH sensing. These findings thus contribute novel insights into the pathophysiology of bipolar mood disorder and other psychiatric diseases.« less

Applications of Gene Targeting Technology to Mental Retardation and Developmental Disability Research

ERIC Educational Resources Information Center

Pimenta, Aurea F.; Levitt, Pat

2005-01-01

The human and mouse genome projects elucidated the sequence and position map of innumerous genes expressed in the central nervous system (CNS), advancing our ability to manipulate these sequences and create models to investigate regulation of gene expression and function. In this article, we reviewed gene targeting methodologies with emphasis on…

76 FR 72713 - Government-Owned Inventions; Availability for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-25

... pitfall to avermectins is central nervous system (CNS) toxicities in herding dogs. As a result, all new... containing the canine wild-type gene (Yancy 2 line). The paired mouse system can be utilized to assess the... xerostomia (dry mouth) that is caused by immune system attack on moisture producing salivary glands...

Gpr124 is essential for blood-brain barrier integrity in central nervous system disease.

PubMed

Chang, Junlei; Mancuso, Michael R; Maier, Carolina; Liang, Xibin; Yuki, Kanako; Yang, Lu; Kwong, Jeffrey W; Wang, Jing; Rao, Varsha; Vallon, Mario; Kosinski, Cynthia; Zhang, J J Haijing; Mah, Amanda T; Xu, Lijun; Li, Le; Gholamin, Sharareh; Reyes, Teresa F; Li, Rui; Kuhnert, Frank; Han, Xiaoyuan; Yuan, Jenny; Chiou, Shin-Heng; Brettman, Ari D; Daly, Lauren; Corney, David C; Cheshier, Samuel H; Shortliffe, Linda D; Wu, Xiwei; Snyder, Michael; Chan, Pak; Giffard, Rona G; Chang, Howard Y; Andreasson, Katrin; Kuo, Calvin J

2017-04-01

Although blood-brain barrier (BBB) compromise is central to the etiology of diverse central nervous system (CNS) disorders, endothelial receptor proteins that control BBB function are poorly defined. The endothelial G-protein-coupled receptor (GPCR) Gpr124 has been reported to be required for normal forebrain angiogenesis and BBB function in mouse embryos, but the role of this receptor in adult animals is unknown. Here Gpr124 conditional knockout (CKO) in the endothelia of adult mice did not affect homeostatic BBB integrity, but resulted in BBB disruption and microvascular hemorrhage in mouse models of both ischemic stroke and glioblastoma, accompanied by reduced cerebrovascular canonical Wnt-β-catenin signaling. Constitutive activation of Wnt-β-catenin signaling fully corrected the BBB disruption and hemorrhage defects of Gpr124-CKO mice, with rescue of the endothelial gene tight junction, pericyte coverage and extracellular-matrix deficits. We thus identify Gpr124 as an endothelial GPCR specifically required for endothelial Wnt signaling and BBB integrity under pathological conditions in adult mice. This finding implicates Gpr124 as a potential therapeutic target for human CNS disorders characterized by BBB disruption.

Lipid metabolism in myelinating glial cells: lessons from human inherited disorders and mouse models.

PubMed

Chrast, Roman; Saher, Gesine; Nave, Klaus-Armin; Verheijen, Mark H G

2011-03-01

The integrity of central and peripheral nervous system myelin is affected in numerous lipid metabolism disorders. This vulnerability was so far mostly attributed to the extraordinarily high level of lipid synthesis that is required for the formation of myelin, and to the relative autonomy in lipid synthesis of myelinating glial cells because of blood barriers shielding the nervous system from circulating lipids. Recent insights from analysis of inherited lipid disorders, especially those with prevailing lipid depletion and from mouse models with glia-specific disruption of lipid metabolism, shed new light on this issue. The particular lipid composition of myelin, the transport of lipid-associated myelin proteins, and the necessity for timely assembly of the myelin sheath all contribute to the observed vulnerability of myelin to perturbed lipid metabolism. Furthermore, the uptake of external lipids may also play a role in the formation of myelin membranes. In addition to an improved understanding of basic myelin biology, these data provide a foundation for future therapeutic interventions aiming at preserving glial cell integrity in metabolic disorders.

Lipid metabolism in myelinating glial cells: lessons from human inherited disorders and mouse models

PubMed Central

Chrast, Roman; Saher, Gesine; Nave, Klaus-Armin; Verheijen, Mark H. G.

2011-01-01

The integrity of central and peripheral nervous system myelin is affected in numerous lipid metabolism disorders. This vulnerability was so far mostly attributed to the extraordinarily high level of lipid synthesis that is required for the formation of myelin, and to the relative autonomy in lipid synthesis of myelinating glial cells because of blood barriers shielding the nervous system from circulating lipids. Recent insights from analysis of inherited lipid disorders, especially those with prevailing lipid depletion and from mouse models with glia-specific disruption of lipid metabolism, shed new light on this issue. The particular lipid composition of myelin, the transport of lipid-associated myelin proteins, and the necessity for timely assembly of the myelin sheath all contribute to the observed vulnerability of myelin to perturbed lipid metabolism. Furthermore, the uptake of external lipids may also play a role in the formation of myelin membranes. In addition to an improved understanding of basic myelin biology, these data provide a foundation for future therapeutic interventions aiming at preserving glial cell integrity in metabolic disorders. PMID:21062955

Expression of LIM-homeodomain transcription factors in the developing and mature mouse retina

PubMed Central

Balasubramanian, Revathi; Bui, Andrew; Ding, Qian; Gan, Lin

2014-01-01

LIM-homeodomain (LIM-HD) transcription factors have been extensively studied for their role in the development of the central nervous system. Their function is key to several developmental events like cell proliferation, differentiation and subtype specification. However, their roles in retinal neurogenesis remain largely unknown. Here we report a detailed expression study of LIM-HD transcription factors LHX9 and LHX2, LHX3 and LHX4, and LHX6 in the developing and mature mouse retina using immunohistochemistry and in situ hybridization techniques. We show that LHX9 is expressed during the early stages of development in the retinal ganglion cell layer and the inner nuclear layer. We also show that LHX9 is expressed in a subset of amacrine cells in the adult retina. LHX2 is known to be expressed in retinal progenitor cells during development and in Müller glial cells and a subset of amacrine cells in the adult retina. We found that the LHX2 subset of amacrine cells is not cholinergic and that a very few of LHX2 amacrine cells express calretinin. LHX3 and LHX4 are expressed in a subset of bipolar cells in the adult retina. LHX6 is expressed in cells in the ganglion cell layer and the neuroblast layer starting at embryonic stage 13.5 (E13.5) and continues to be expressed in cells in the ganglion cell layer and inner nuclear layer, postnatally, suggesting its likely expression in amacrine cells or a subset thereof. Taken together, our comprehensive assay of expression patterns of LIM-HD transcription factors during mouse retinal development will help further studies elucidating their biological functions in the differentiation of retinal cell subtypes. PMID:24333658

A brain-specific gene cluster isolated from the region of the mouse obesity locus is expressed in the adult hypothalamus and during mouse development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laig-Webster, M.; Lim, M.E.; Chehab, F.F.

1994-09-01

The molecular defect underlying an autosomal recessive form of genetic obesity in a classical mouse model C57 BL/6J-ob/ob has not yet been elucidated. Whereas metabolic and physiological disturbances such as diabetes and hypertension are associated with obesity, the site of expression and the nature of the primary lesion responsible for this cascade of events remains elusive. Our efforts aimed at the positional cloning of the ob gene by YAC contig mapping and gene identification have resulted in the cloning of a brain-specific gene cluster from the ob critical region. The expression of this gene cluster is remarkably complex owing tomore » the multitude of brain-specific mRNA transcripts detected on Northern blots. cDNA cloning of these transcripts suggests that they are expressed from different genes as well as by alternate splicing mechanisms. Furthermore, the genomic organization of the cluster appears to consist of at least two identical promoters displaying CpG islands characteristic of housekeeping genes, yet clearly involving tissue-specific expression. Sense and anti-sense synthetic RNA probes were derived from a common DNA sequence on 3 cDNA clones and hybridized to 8-16 days mouse embryonic stages and mouse adult brain sections. Expression in development was noticeable as of the 11th day of gestation and confined to the central nervous system mainly in the telencephalon and spinal cord. Coronal and sagittal sections of the adult mouse brain showed expression only in 3 different regions of the brain stem. In situ hybridization to mouse hypothalamus sections revealed the presence of a localized and specialized group of cells expressing high levels of mRNA, suggesting that this gene cluster may also be involved in the regulation of hypothalamic activities. The hypothalamus has long been hypothesized as a primary candidate tissue for the expression of the obesity gene mainly because of its well-established role in the regulation of energy metabolism and food intake.« less

The Role of Oxidative Stress in Nervous System Aging

PubMed Central

Sims-Robinson, Catrina; Hur, Junguk; Hayes, John M.; Dauch, Jacqueline R.; Keller, Peter J.; Brooks, Susan V.; Feldman, Eva L.

2013-01-01

While oxidative stress is implicated in aging, the impact of oxidative stress on aging in the peripheral nervous system is not well understood. To determine a potential mechanism for age-related deficits in the peripheral nervous system, we examined both functional and morphological changes and utilized microarray technology to compare normal aging in wild-type mice to effects in copper/zinc superoxide dismutase-deficient (Sod1−/−) mice, a mouse model of increased oxidative stress. Sod1−/− mice exhibit a peripheral neuropathy phenotype with normal sensory nerve function and deficits in motor nerve function. Our data indicate that a decrease in the synthesis of cholesterol, which is vital to myelin formation, correlates with the structural deficits in axons, myelin, and the cell body of motor neurons in the Sod1+/+ mice at 30 months and the Sod1−/− mice at 20 months compared with mice at 2 months. Collectively, we have demonstrated that the functional and morphological changes within the peripheral nervous system in our model of increased oxidative stress are manifested earlier and resemble the deficits observed during normal aging. PMID:23844146

The role of oxidative stress in nervous system aging.

PubMed

Sims-Robinson, Catrina; Hur, Junguk; Hayes, John M; Dauch, Jacqueline R; Keller, Peter J; Brooks, Susan V; Feldman, Eva L

2013-01-01

While oxidative stress is implicated in aging, the impact of oxidative stress on aging in the peripheral nervous system is not well understood. To determine a potential mechanism for age-related deficits in the peripheral nervous system, we examined both functional and morphological changes and utilized microarray technology to compare normal aging in wild-type mice to effects in copper/zinc superoxide dismutase-deficient (Sod1(-/-)) mice, a mouse model of increased oxidative stress. Sod1(-/-) mice exhibit a peripheral neuropathy phenotype with normal sensory nerve function and deficits in motor nerve function. Our data indicate that a decrease in the synthesis of cholesterol, which is vital to myelin formation, correlates with the structural deficits in axons, myelin, and the cell body of motor neurons in the Sod1(+/+) mice at 30 months and the Sod1(-/-) mice at 20 months compared with mice at 2 months. Collectively, we have demonstrated that the functional and morphological changes within the peripheral nervous system in our model of increased oxidative stress are manifested earlier and resemble the deficits observed during normal aging.

Engineered AAVs for efficient noninvasive gene delivery to the central and peripheral nervous systems

PubMed Central

Chan, Ken Y; Jang, Min J; Yoo, Bryan B; Greenbaum, Alon; Ravi, Namita; Wu, Wei-Li; Sánchez-Guardado, Luis; Lois, Carlos; Mazmanian, Sarkis K; Deverman, Benjamin E; Gradinaru, Viviana

2017-01-01

Adeno-associated viruses (AAVs) are commonly used for in vivo gene transfer. Nevertheless, AAVs that provide efficient transduction across specific organs or cell populations are needed. Here, we describe AAV-PHP.eB and AAV-PHP.S, capsids that efficiently transduce the central and peripheral nervous systems, respectively. In the adult mouse, intravenous administration of 1×1011 vector genomes (vg) of AAV-PHP.eB transduced 69% of cortical and 55% of striatal neurons, while 1×1012 vg AAV-PHP.S transduced 82% of dorsal root ganglion neurons, as well as cardiac and enteric neurons. The efficiency of these vectors facilitates robust co-transduction and stochastic, multicolor labeling for individual cell morphology studies. To support such efforts, we provide methods for labeling a tunable fraction of cells without compromising color diversity. Furthermore, when used with cell type-specific promoters, these AAVs provide targeted gene expression across the nervous system and enable efficient and versatile gene manipulation throughout the nervous system of transgenic and non-transgenic animals. PMID:28671695

High-Affinity Binding of Remyelinating Natural Autoantibodies to Myelin-Mimicking Lipid Bilayers Revealed by Nanohole Surface Plasmon Resonance

PubMed Central

Wittenberg, Nathan J.; Im, Hyungsoon; Xu, Xiaohua; Wootla, Bharath; Watzlawik, Jens; Warrington, Arthur E.; Rodriguez, Moses; Oh, Sang-Hyun

2012-01-01

Multiple sclerosis is a progressive neurological disorder that results in the degradation of myelin sheaths that insulate axons in the central nervous system. Therefore promotion of myelin repair is a major thrust of multiple sclerosis treatment research. Two mouse monoclonal natural autoantibodies, O1 and O4, promote myelin repair in several mouse models of multiple sclerosis. Natural autoantibodies are generally polyreactive and predominantly of the IgM isotype. The prevailing paradigm is that because they are polyreactive, these antibodies bind antigens with low affinities. Despite their wide use in neuroscience and glial cell research, however, the affinities and kinetic constants of O1 and O4 antibodies have not been measured to date. In this work, we developed a membrane biosensing platform based on surface plasmon resonance in gold nanohole arrays with a series of surface modification techniques to form myelin-mimicking lipid bilayer membranes to measure both the association and dissociation rate constants for O1 and O4 antibodies binding to their myelin lipid antigens. The ratio of rate constants shows that O1 and O4 bind to galactocerebroside and sulfated galactocerebroside, respectively, with unusually small apparent dissociation constants (KD ~0.9 nM) for natural autoantibodies. This is approximately one to two orders of magnitude lower than typically observed for the highest affinity natural autoantibodies. We propose that the unusually high affinity of O1 and O4 to their targets in myelin contributes to the mechanism by which they signal oligodendrocytes and induce central nervous system repair. PMID:22762372

Increase in peripheral oxidative stress during hypercholesterolemia is not reflected in the central nervous system: evidence from two mouse models.

PubMed

Ding, Tao; Yao, Yeumang; Praticò, Domenico

2005-05-01

In recent years oxidative stress has been widely implicated as a pathogenetic mechanism of several diseases, and a variety of indices and assays have been developed to assess this phenomenon in complex biological systems. Most of these biomarkers can be measured virtually in every biological fluid and tissue, providing us with the opportunity to assess their formation at local site of oxidative injury. However, despite their widespread use, it is still not completely clear how their peripheral formation correlates with the levels measured in the central nervous system. For this reason, we utilized two well-characterized animal models of chronic peripheral oxidative stress, low-density lipoprotein receptor (LDLR)-deficient and C57BL/6 mice on a high fat diet. After 8 weeks on the diet, we assessed isoprostane, marker of lipid peroxidation, and carbonyls, marker of protein oxidation, in several organs of these animals. Compared with animals on chow, mice on the high fat diet showed a significant increase in both biomarkers in plasma, heart, aorta and liver but not in brain tissues. This observation was confirmed by the selective accumulation of radioactivity in the peripheral organs but not in the brains of mice injected with tritiated isoprostane. Our findings indicate that in hypercholesterolemia the peripheral formation of oxidative products does not contribute to their levels found in the central nervous system.

Direct visualization of membrane architecture of myelinating cells in transgenic mice expressing membrane-anchored EGFP.

PubMed

Deng, Yaqi; Kim, BongWoo; He, Xuelian; Kim, Sunja; Lu, Changqing; Wang, Haibo; Cho, Ssang-Goo; Hou, Yiping; Li, Jianrong; Zhao, Xianghui; Lu, Q Richard

2014-04-01

Myelinogenesis is a complex process that involves substantial and dynamic changes in plasma membrane architecture and myelin interaction with axons. Highly ramified processes of oligodendrocytes in the central nervous system (CNS) make axonal contact and then extrapolate to wrap around axons and form multilayer compact myelin sheathes. Currently, the mechanisms governing myelin sheath assembly and axon selection by myelinating cells are not fully understood. Here, we generated a transgenic mouse line expressing the membrane-anchored green fluorescent protein (mEGFP) in myelinating cells, which allow live imaging of details of myelinogenesis and cellular behaviors in the nervous systems. mEGFP expression is driven by the promoter of 2'-3'-cyclic nucleotide 3'-phosphodiesterase (CNP) that is expressed in the myelinating cell lineage. Robust mEGFP signals appear in the membrane processes of oligodendrocytes in the CNS and Schwann cells in the peripheral nervous system (PNS), wherein mEGFP expression defines the inner layers of myelin sheaths and Schmidt-Lanterman incisures in adult sciatic nerves. In addition, mEGFP expression can be used to track the extent of remyelination after demyelinating injury in a toxin-induced demyelination animal model. Taken together, the membrane-anchored mEGFP expression in the new transgenic line would facilitate direct visualization of dynamic myelin membrane formation and assembly during development and process remodeling during remyelination after various demyelinating injuries.

Protein arginine Methyltransferase 8 gene is expressed in pluripotent stem cells and its expression is modulated by the transcription factor Sox2.

PubMed

Solari, Claudia; Echegaray, Camila Vázquez; Luzzani, Carlos; Cosentino, María Soledad; Waisman, Ariel; Petrone, María Victoria; Francia, Marcos; Sassone, Alina; Canizo, Jésica; Sevlever, Gustavo; Barañao, Lino; Miriuka, Santiago; Guberman, Alejandra

2016-04-22

Addition of methyl groups to arginine residues is catalyzed by a group of enzymes called Protein Arginine Methyltransferases (Prmt). Although Prmt1 is essential in development, its paralogue Prmt8 has been poorly studied. This gene was reported to be expressed in nervous system and involved in neurogenesis. In this work, we found that Prmt8 is expressed in mouse embryonic stem cells (ESC) and in induced pluripotent stem cells, and modulated along differentiation to neural precursor cells. We found that Prmt8 promoter activity is induced by the pluripotency transcription factors Oct4, Sox2 and Nanog. Moreover, endogenous Prmt8 mRNA levels were reduced in ESC transfected with Sox2 shRNA vector. As a whole, our results indicate that Prmt8 is expressed in pluripotent stem cells and its transcription is modulated by pluripotency transcription factors. These findings suggest that besides its known function in nervous system, Prmt8 could play a role in pluripotent stem cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Quantification of mesembrine and mesembrenone in mouse plasma using UHPLC-QToF-MS: Application to a pharmacokinetic study

USDA-ARS?s Scientific Manuscript database

Sceletium tortuosum, commonly named as Kanna, or Channa, is an indigenous herb of South Africa. Traditionally, the plant is consumed in the form of a tincture, chewing dried leaves or smoking and is widely used in the treatment of central nervous system (CNS) related disorders such as anxiety, depre...

Raman spectroscopy reveals spectroscopic changes in histologically normal retinas in a mouse model of alpha-synucleinopathy

USDA-ARS?s Scientific Manuscript database

The retina is an extension of the nervous system and is accessible for in vivo assessments. We have previously demonstrated changes in retinal function and pathology associated with scrapie, TME and BSE. The purpose of this work was to determine the utility of the retina to identify early CNS change...

Optimizing biologically targeted clinical trials for neurofibromatosis

PubMed Central

Gutmann, David H; Blakeley, Jaishri O; Korf, Bruce R; Packer, Roger J

2014-01-01

Introduction The neurofibromatoses (neurofibromatosis type 1, NF1 and neurofibromatosis type 2, NF2) comprise the most common inherited conditions in which affected children and adults develop tumors of the central and peripheral nervous system. In this review, the authors discuss how the establishment of the Neurofibromatosis Clinical Trials Consortium (NFCTC) has positively impacted on the design and execution of treatment studies for individuals with NF1 and NF2. Areas covered Using an extensive PUBMED search in collaboration with select NFCTC members expert in distinct NF topics, the authors discuss the clinical features of NF1 and NF2, the molecular biology of the NF1 and NF2 genes, the development and application of clinically relevant Nf1 and Nf2 genetically engineered mouse models and the formation of the NFCTC to enable efficient clinical trial design and execution. Expert opinion The NFCTC has resulted in a more seamless integration of mouse preclinical and human clinical trials efforts. Leveraging emerging enabling resources, current research is focused on identifying subtypes of tumors in NF1 and NF2 to deliver the most active compounds to the patients most likely to respond to the targeted therapy. PMID:23425047

Regulation of Microglia Identity from an Epigenetic and Transcriptomic Point of View.

PubMed

Eggen, Bart J L; Boddeke, Erik W G M; Kooistra, Susanne M

2017-12-14

Microglia have long been recognized as the endogenous innate immune elements in the central nervous system (CNS) parenchyma. Besides fulfilling local immune-related functions, they provide cross-talk between the CNS and the immune system at large. In the adult CNS, microglia are involved in maintaining brain homeostasis, modulating synaptic transmission and clearance of apoptotic cells. During embryonic development, microglia are responsible for the removal of supernumerary synapses and neurons, and neuronal network formation. The full scale of their potential abilities has been highlighted by improvements in microglia isolation methods, the development of genetically tagged mouse models, advanced imaging technologies and the application of next-generation sequencing in recent years. Genome-wide expression analysis of relatively pure microglia populations from both mouse and human CNS tissues has thereby greatly contributed to our knowledge of their biology; what defines them under homeostatic conditions and how microglia respond to processes like aging and CNS disease? How and to what degree beneficial functions of microglia can be restored in the aged or diseased brain will be the key issue to be addressed in future research. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Neuropathology and functional deficits in a model of birth asphyxia in the precocial spiny mouse (Acomys cahirinus).

PubMed

Hutton, Lisa C; Ratnayake, Udani; Shields, Amy; Walker, David W

2009-01-01

Birth asphyxia can result in sensory impairment, learning and memory deficits without gross brain injury and severe motor deficits. We developed a model of birth asphyxia resulting in mild neurological injury and cognitive impairment using a long-gestation species with precocial fetal development. Spiny mice (Acomys cahirinus) underwent caesarean-section delivery or 7.5 min of asphyxia at 37 days gestational age (term is 39 days). Brain histology was examined at 1 and 7 days of age, and behaviour was evaluated to 28 days of age. Asphyxiated offspring showed significant impairment in non-spatial memory and learning tasks, accompanied by central nervous system inflammation and increased apoptotic cell death but without the presence of large necrotic or cystic lesions. Copyright 2009 S. Karger AG, Basel.

Multiple protocadherins are expressed in brain microvascular endothelial cells and might play a role in tight junction protein regulation.

PubMed

Dilling, Christina; Roewer, Norbert; Förster, Carola Y; Burek, Malgorzata

2017-10-01

Protocadherins (Pcdhs) are a large family of cadherin-related molecules. They play a role in cell adhesion, cellular interactions, and development of the central nervous system. However, their expression and role in endothelial cells has not yet been characterized. Here, we examined the expression of selected clustered Pcdhs in endothelial cells from several vascular beds. We analyzed human and mouse brain microvascular endothelial cell (BMEC) lines and primary cells, mouse myocardial microvascular endothelial cell line, and human umbilical vein endothelial cells. We examined the mRNA and protein expression of selected Pcdhs using RT-PCR, Western blot, and immunostaining. A strong mRNA expression of Pcdhs was observed in all endothelial cells tested. At the protein level, Pcdhs-gamma were detected using an antibody against the conserved C-terminal domain of Pcdhs-gamma or an antibody against PcdhgC3. Deletion of highly expressed PcdhgC3 led to differences in the tight junction protein expression and mRNA expression of Wnt/mTOR (mechanistic target of rapamycin) pathway genes as well as lower transendothelial electrical resistance. Staining of PcdhgC3 showed diffused cytoplasmic localization in mouse BMEC. Our results suggest that Pcdhs may play a critical role in the barrier-stabilizing pathways at the blood-brain barrier.

Reprogrammed mouse astrocytes retain a "memory" of tissue origin and possess more tendencies for neuronal differentiation than reprogrammed mouse embryonic fibroblasts.

PubMed

Tian, Changhai; Wang, Yongxiang; Sun, Lijun; Ma, Kangmu; Zheng, Jialin C

2011-02-01

Direct reprogramming of a variety of somatic cells with the transcription factors Oct4 (also called Pou5f1), Sox2 with either Klf4 and Myc or Lin28 and Nanog generates the induced pluripotent stem cells (iPSCs) with marker similarity to embryonic stem cells. However, the difference between iPSCs derived from different origins is unclear. In this study, we hypothesized that reprogrammed cells retain a "memory" of their origins and possess additional potential of related tissue differentiation. We reprogrammed primary mouse astrocytes via ectopic retroviral expression of OCT3/4, Sox2, Klf4 and Myc and found the iPSCs from mouse astrocytes expressed stem cell markers and formed teratomas in SCID mice containing derivatives of all three germ layers similar to mouse embryonic stem cells besides semblable morphologies. To test our hypothesis, we compared embryonic bodies (EBs) formation and neuronal differentiation between iPSCs from mouse embryonic fibroblasts (MEFsiPSCs) and iPSCs from mouse astrocytes (mAsiPSCs). We found that mAsiPSCs grew slower and possessed more potential for neuronal differentiation compared to MEFsiPSCs. Our results suggest that mAsiPSCs retain a "memory" of the central nervous system, which confers additional potential upon neuronal differentiation.

Minimal Phenotype of Mice Homozygous for a Null Mutation in the Forkhead/Winged Helix Gene, Mf2

PubMed Central

Kume, Tsutomu; Deng, Keyu; Hogan, Brigid L. M.

2000-01-01

Mf2 (mesoderm/mesenchyme forkhead 2) encodes a forkhead/winged helix transcription factor expressed in numerous tissues of the mouse embryo, including paraxial mesoderm, somites, branchial arches, vibrissae, developing central nervous system, and developing kidney. We have generated mice homozygous for a null mutation in the Mf2 gene (Mf2lacZ) to examine its role during embryonic development. The lacZ allele also allows monitoring of Mf2 gene expression. Homozygous null mutants are viable and fertile and have no major developmental defects. Some mutants show renal abnormalities, including kidney hypoplasia and hydroureter, but the penetrance of this phenotype is only 40% or lower, depending on the genetic background. These data suggest that Mf2 can play a unique role in kidney development, but there is functional redundancy in this organ and other tissues with other forkhead/winged helix genes. PMID:10648626

Minimal phenotype of mice homozygous for a null mutation in the forkhead/winged helix gene, Mf2.

PubMed

Kume, T; Deng, K; Hogan, B L

2000-02-01

Mf2 (mesoderm/mesenchyme forkhead 2) encodes a forkhead/winged helix transcription factor expressed in numerous tissues of the mouse embryo, including paraxial mesoderm, somites, branchial arches, vibrissae, developing central nervous system, and developing kidney. We have generated mice homozygous for a null mutation in the Mf2 gene (Mf2(lacZ)) to examine its role during embryonic development. The lacZ allele also allows monitoring of Mf2 gene expression. Homozygous null mutants are viable and fertile and have no major developmental defects. Some mutants show renal abnormalities, including kidney hypoplasia and hydroureter, but the penetrance of this phenotype is only 40% or lower, depending on the genetic background. These data suggest that Mf2 can play a unique role in kidney development, but there is functional redundancy in this organ and other tissues with other forkhead/winged helix genes.

The mouse cerebellar cortex in organotypic slice cultures: an in vitro model to analyze the consequences of mutations and pathologies on neuronal survival, development, and function.

PubMed

Lonchamp, Etienne; Dupont, Jean-Luc; Beekenkamp, Huguette; Poulain, Bernard; Bossu, Jean-Louis

2006-01-01

Thin acute slices and dissociated cell cultures taken from different parts of the brain have been widely used to examine the function of the nervous system, neuron-specific interactions, and neuronal development (specifically, neurobiology, neuropharmacology, and neurotoxicology studies). Here, we focus on an alternative in vitro model: brain-slice cultures in roller tubes, initially introduced by Beat Gähwiler for studies with rats, that we have recently adapted for studies of mouse cerebellum. Cultured cerebellar slices afford many of the advantages of dissociated cultures of neurons and thin acute slices. Organotypic slice cultures were established from newborn or 10-15-day-old mice. After 3-4 weeks in culture, the slices flattened to form a cell monolayer. The main types of cerebellar neurons could be identified with immunostaining techniques, while their electrophysiological properties could be easily characterized with the patch-clamp recording technique. When slices were taken from newborn mice and cultured for 3 weeks, aspects of the cerebellar development were displayed. A functional neuronal network was established despite the absence of mossy and climbing fibers, which are the two excitatory afferent projections to the cerebellum. When slices were made from 10-15-day-old mice, which are at a developmental stage when cerebellum organization is almost established, the structure and neuronal pathways were intact after 3-4 weeks in culture. These unique characteristics make organotypic slice cultures of mouse cerebellar cortex a valuable model for analyzing the consequences of gene mutations that profoundly alter neuronal function and compromise postnatal survival.

Sema4D/CD100 deficiency leads to superior performance in mouse motor behavior.

PubMed

Yukawa, Kazunori; Tanaka, Tetsuji; Takeuchi, Noriko; Iso, Hiroyuki; Li, Li; Kohsaka, Akira; Waki, Hidefumi; Miyajima, Masayasu; Maeda, Masanobu; Kikutani, Hitoshi; Kumanogoh, Atsushi

2009-05-01

Sema4D/CD100 is a type of class 4 semaphorin, exhibiting crucial roles in growth cone guidance in developing neurons. Sema4D is widely expressed throughout the central nervous system in embryonic mouse brain, and is selectively localized to oligodendrocytes and myelin in the postnatal brain. However, direct evidence of the actual involvement of Sema4D in the neuronal network development crucial for neurobehavioral performance is still lacking. The present study therefore examined whether Sema4D deficiency leads to abnormal behavioral development. Both wild-type and Sema4D-deficient mice were subjected to behavioral analyses including open-field, adhesive tape removal, rotarod tests and a water maze task. Open-field tests revealed increased locomotor activity in Sema4D-deficient mice with less percentage of time spent in the center of the field. In both the adhesive tape removal and rotarod tests, which examine motor coordination and balance, Sema4D-deficient mice showed significantly superior performance, suggesting facilitated motor behavior. Both Sema4D-deficient and wild-type mice successfully learnt the water maze task, locating a hidden escape platform, and also showed precise memory for the platform position in probe tests. However, the swimming speed of Sema4D-deficient mice was significantly faster than that of wild-type mice, providing further evidence of their accelerated motor behavior. Our mouse behavioral analyses revealed enhanced motor activity in Sema4D-deficient mice, suggesting the crucial involvement of Sema4D in the neurodevelopmental processes of the central structures mediating motor behavior in mice.

Glucosylceramide Administration as a Vaccination Strategy in Mouse Models of Cryptococcosis

PubMed Central

Mor, Visesato; Farnoud, Amir M.; Singh, Ashutosh; Rella, Antonella; Tanno, Hiromasa; Ishii, Keiko; Kawakami, Kazuyoshi; Sato, Toshiya; Del Poeta, Maurizio

2016-01-01

Cryptococcus neoformans is an opportunistic fungal pathogen and the causative agent of the disease cryptococcosis. Cryptococcosis is initiated as a pulmonary infection and in conditions of immune deficiency disseminates to the blood stream and central nervous system, resulting in life-threatening meningoencephalitis. A number of studies have focused on the development of a vaccine against Cryptococcus, primarily utilizing protein-conjugated components of the Cryptococcus polysaccharide capsule as antigen. However, there is currently no vaccine against Cryptococcus in the clinic. Previous studies have shown that the glycosphingolipid, glucosylceramide (GlcCer), is a virulence factor in C. neoformans and antibodies against this lipid inhibit fungal growth and cell division. In the present study, we have investigated the possibility of using GlcCer as a therapeutic agent against C. neoformans infections in mouse models of cryptococcosis. GlcCer purified from a non-pathogenic fungus, Candida utilis, was administered intraperitoneally, prior to infecting mice with a lethal dose of C. neoformans. GlcCer administration prevented the dissemination of C. neoformans from the lungs to the brain and led to 60% mouse survival. GlcCer administration did not cause hepatic injury and elicited an anti-GlcCer antibody response, which was observed independent of the route of administration and the strains of mouse. Taken together, our results suggest that fungal GlcCer can protect mice against lethal doses of C. neoformans infection and can provide a viable vaccination strategy against Cryptococcus. PMID:27082428

NBQX, a highly selective competitive antagonist of AMPA and KA ionotropic glutamate receptors, increases seizures and mortality following picornavirus infection.

PubMed

Libbey, Jane E; Hanak, Tyler J; Doty, Daniel J; Wilcox, Karen S; Fujinami, Robert S

2016-06-01

Seizures occur due to an imbalance between excitation and inhibition, with the balance tipping towards excitation, and glutamate is the predominant excitatory neurotransmitter in the central nervous system of mammals. Since upregulation of expression and/or function of glutamate receptors can contribute to seizures we determined the effects of three antagonists, NBQX, GYKI-52466 and MK 801, of the various ionotropic glutamate receptors, AMPA, NMDA and KA, on acute seizure development in the Theiler's murine encephalomyelitis virus (TMEV)-induced seizure model. We found that only NBQX had an effect on acute seizure development, resulting in a significantly higher number of mice experiencing seizures, an increase in the number of seizures per mouse, a greater cumulative seizure score per mouse and a significantly higher mortality rate among the mice. Although NBQX has previously been shown to be a potent anticonvulsant in animal seizure models, seizures induced by electrical stimulation, drug administration or as a result of genetic predisposition may differ greatly in terms of mechanism of seizure development from our virus-induced seizure model, which could explain the opposite, proconvulsant effect of NBQX observed in the TMEV-induced seizure model. Copyright © 2016 Elsevier Inc. All rights reserved.

The development of colon innervation in trisomy 16 mice and Hirschsprungs disease

PubMed Central

Li, Ji Cheng; Mi, Kai Hong; Zhou, Ji Lin; Busch, LC; Kuhnel, W

2001-01-01

AIM: To study the colon innervation of trisomy 16 mouse, an animal model for Down’s syndrome, and the expression of protein gene product 9.5 (PGP 9.5) in the stenosed segment of colon in Hirschsprungs disease (HD). METHODS: Trisomy 16 mouse breeding; cytogenetic analysis of trisomy 16 mice; and PGP 9.5 immunohistochemistry of colons of trisomy 16 mice and HD were carried out. RESULTS: Compared with their normal littermates, the nervous system of colon in trisomy 16 mice was abnormally developed. There existed developmental delay of muscular plexuses of colon, no submucosal plexus was found in the colon, and there was 5 mm aganglionic bowel aparting from the anus in trisomy 16 mice. The mesentery nerve fibers were as well developed as shown in their normal littermates. Abundant proliferation of PGP 9.5 positive nerve fibers was evealed in the stenosed segment of HD colon. CONCLUSION: Trisomy 16 mice could serve as an animal model for Hirschsprung’s disease for aganglionic bowel in the distal part of colon. Abundant proliferation of PGP 9.5 positive fibers resulted from extrinsic nerve compensation, since no ganglionic cells were observed in the stenosed segment of the colon in HD. HD has a genetic tendency. PMID:11819726

Reduced endothelin converting enzyme-1 and endothelin-3 mRNA in the developing bowel of male mice may increase expressivity and penetrance of Hirschsprung disease-like distal intestinal aganglionosis.

PubMed

Vohra, Bhupinder P S; Planer, William; Armon, Jennifer; Fu, Ming; Jain, Sanjay; Heuckeroth, Robert O

2007-01-01

Hirschsprung disease (distal intestinal aganglionosis, HSCR) is a multigenic disorder with incomplete penetrance, variable expressivity, and a strong male gender bias. Recent studies demonstrated that these genetic patterns arise because gene interactions determine whether enteric nervous system (ENS) precursors successfully proliferate and migrate into the distal bowel. We now demonstrate that male gender bias in the extent of distal intestinal aganglionosis occurs in mice with Ret dominant-negative mutations (RetDN) that mimic human HSCR. We hypothesized that male gender bias could result from reduced expression of a gene already known to be essential for ENS development. Using quantitative real-time polymerase chain reaction (PCR) we demonstrated reduced levels of endothelin converting enzyme-1 and endothelin-3 mRNA in the male mouse bowel at the time that ENS precursors migrate into the colon. Other HSCR-associated genes are expressed at comparable levels in male and female mice. Testosterone and Mullerian inhibiting substance had no deleterious effect on ENS precursor development, but adding EDN3 peptide to E11.5 male RetDN heterozygous mouse gut explants in organ culture significantly increased the rate of ENS precursor migration through the bowel.

Whole-brain ex-vivo quantitative MRI of the cuprizone mouse model

PubMed Central

Hurley, Samuel A.; Vernon, Anthony C.; Torres, Joel; Dell’Acqua, Flavio; Williams, Steve C.R.; Cash, Diana

2016-01-01

Myelin is a critical component of the nervous system and a major contributor to contrast in Magnetic Resonance (MR) images. However, the precise contribution of myelination to multiple MR modalities is still under debate. The cuprizone mouse is a well-established model of demyelination that has been used in several MR studies, but these have often imaged only a single slice and analysed a small region of interest in the corpus callosum. We imaged and analyzed the whole brain of the cuprizone mouse ex-vivo using high-resolution quantitative MR methods (multi-component relaxometry, Diffusion Tensor Imaging (DTI) and morphometry) and found changes in multiple regions, including the corpus callosum, cerebellum, thalamus and hippocampus. The presence of inflammation, confirmed with histology, presents difficulties in isolating the sensitivity and specificity of these MR methods to demyelination using this model. PMID:27833805

Structural features of a close homologue of L1 (CHL1) in the mouse: a new member of the L1 family of neural recognition molecules.

PubMed

Holm, J; Hillenbrand, R; Steuber, V; Bartsch, U; Moos, M; Lübbert, H; Montag, D; Schachner, M

1996-08-01

We have identified a close homologue of L1 (CHL1) in the mouse. CHL1 comprises an N-terminal signal sequence, six immunoglobulin (Ig)-like domains, 4.5 fibronectin type III (FN)-like repeats, a transmembrane domain and a C-terminal, most likely intracellular domain of approximately 100 amino acids. CHL1 is most similar in its extracellular domain to chicken Ng-CAM (approximately 40% amino acid identity), followed by mouse L1, chicken neurofascin, chicken Nr-CAM, Drosophila neuroglian and zebrafish L1.1 (37-28% amino acid identity), and mouse F3, rat TAG-1 and rat BIG-1 (approximately 27% amino acid identity). The similarity with other members of the Ig superfamily [e.g. neural cell adhesion molecule (N-CAM), DCC, HLAR, rse] is 16-11%. The intracellular domain is most similar to mouse and chicken Nr-CAM, mouse and rat neurofascin (approximately 60% amino acid identity) followed by chicken neurofascin and Ng-CAM, Drosophila neuroglian and zebrafish L1.1 and L1.2 (approximately 40% amino acid identity). Besides the high overall homology and conserved modular structure among previously recognized members of the L1 family (mouse/human L1/rat NILE; chicken Ng-CAM; chicken/mouse Nr-CAM; Drosophila neuroglian; zebrafish L1.1 and L1.2; chicken/mouse neurofascin/rat ankyrin-binding glycoprotein), criteria characteristic of L1 were identified with regard to the number of amino acids between positions of conserved amino acid residues defining distances within and between two adjacent Ig-like domains and FN-like repeats. These show a collinearity in the six Ig-like domains and four adjacent FN-like repeats that is remarkably conserved between L1 and molecules containing these modules (designated the L1 family cassette), including the GPI-linked forms of the F3 subgroup (mouse F3/chicken F11/human CNTN1; rat BIG-1/mouse PANG; rat TAG-1/mouse TAX-1/chicken axonin-1). The colorectal cancer molecule (DCC), previously introduced as an N-CAM-like molecule, conforms to the L1 family cassette. Other structural features of CHL 1 shared between members of the L1 family are a high degree of N-glycosidically linked carbohydrates (approximately 20% of its molecular mass), which include the HNK-1 carbohydrate structure, and a pattern of protein fragments comprising a major 185 kDa band and smaller fragments of 165 and 125 kDa. As for the other L1 family members, predominant expression of CHL1 is observed in the nervous system and at later developmental stages. In the central nervous system CHL1 is expressed by neurons, but, in contrast to L1, also by glial cells. Our findings suggest a common ancestral L1-like molecule which evolved via gene duplication to generate a diversity of structurally and functionally distinct yet similar molecules.

The mouse neuronal cell surface protein F3: a phosphatidylinositol- anchored member of the immunoglobulin superfamily related to chicken contactin

PubMed Central

1989-01-01

Several members of the Ig superfamily are expressed on neural cells where they participate in surface interactions between cell bodies and processes. Their Ig domains are more closely related to each other than to Ig variable and constant domains and have been grouped into the C2 set. Here, we report the cloning and characterization of another member of this group, the mouse neuronal cell surface antigen F3. The F3 cDNA sequence contains an open reading frame that could encode a 1,020-amino acid protein consisting of a signal sequence, six Ig-like domains of the C2 type, a long premembrane region containing two segments that exhibit sequence similarity to fibronectin type III repeats and a moderately hydrophobic COOH-terminal sequence. The protein does not contain a typical transmembrane segment but appears to be attached to the membrane by a phosphatidylinositol anchor. Antibodies against the F3 protein recognize a prominent 135-kD protein in mouse brain. In fetal brain cultures, they stain the neuronal cell surface and, in cultures maintained in chemically defined medium, most prominently neurites and neurite bundles. The mouse f3 gene maps to band F of chromosome 15. The gene transcripts detected in the brain by F3 cDNA probes are developmentally regulated, the highest amounts being expressed between 1 and 2 wk after birth. The F3 nucleotide and deduced amino acid sequence show striking similarity to the recently published sequence of the chicken neuronal cell surface protein contactin. However, there are important differences between the two molecules. In contrast to F3, contactin has a transmembrane and a cytoplasmic domain. Whereas contactin is insoluble in nonionic detergent and is tightly associated with the cytoskeleton, about equal amounts of F3 distribute between buffer-soluble, nonionic detergent-soluble, and detergent- insoluble fractions. Among other neural cell surface proteins, F3 most resembles the neuronal cell adhesion protein L1, with 25% amino acid identity between their extracellular domains. Based on its structural similarity with known cell adhesion proteins of nervous tissue and with L1 in particular, we propose that F3 mediates cell surface interactions during nervous system development. PMID:2474555

Video Imaging and Spatiotemporal Maps to Analyze Gastrointestinal Motility in Mice.

PubMed

Swaminathan, Mathusi; Hill-Yardin, Elisa; Ellis, Melina; Zygorodimos, Matthew; Johnston, Leigh A; Gwynne, Rachel M; Bornstein, Joel C

2016-02-03

The enteric nervous system (ENS) plays an important role in regulating gastrointestinal (GI) motility and can function independently of the central nervous system. Changes in ENS function are a major cause of GI symptoms and disease and may contribute to GI symptoms reported in neuropsychiatric disorders including autism. It is well established that isolated colon segments generate spontaneous, rhythmic contractions known as Colonic Migrating Motor Complexes (CMMCs). A procedure to analyze the enteric neural regulation of CMMCs in ex vivo preparations of mouse colon is described. The colon is dissected from the animal and flushed to remove fecal content prior to being cannulated in an organ bath. Data is acquired via a video camera positioned above the organ bath and converted to high-resolution spatiotemporal maps via an in-house software package. Using this technique, baseline contractile patterns and pharmacological effects on ENS function in colon segments can be compared over 3-4 hr. In addition, propagation length and speed of CMMCs can be recorded as well as changes in gut diameter and contraction frequency. This technique is useful for characterizing gastrointestinal motility patterns in transgenic mouse models (and in other species including rat and guinea pig). In this way, pharmacologically induced changes in CMMCs are recorded in wild type mice and in the Neuroligin-3(R451C) mouse model of autism. Furthermore, this technique can be applied to other regions of the GI tract including the duodenum, jejunum and ileum and at different developmental ages in mice.

Cellular Specificity of the Blood–CSF Barrier for Albumin Transfer across the Choroid Plexus Epithelium

PubMed Central

Liddelow, Shane A.; Dzięgielewska, Katarzyna M.; Møllgård, Kjeld; Whish, Sophie C.; Noor, Natassya M.; Wheaton, Benjamin J.; Gehwolf, Renate; Wagner, Andrea; Traweger, Andreas; Bauer, Hannelore; Bauer, Hans-Christian; Saunders, Norman R.

2014-01-01

To maintain the precise internal milieu of the mammalian central nervous system, well-controlled transfer of molecules from periphery into brain is required. Recently the soluble and cell-surface albumin-binding glycoprotein SPARC (secreted protein acidic and rich in cysteine) has been implicated in albumin transport into developing brain, however the exact mechanism remains unknown. We postulate that SPARC is a docking site for albumin, mediating its uptake and transfer by choroid plexus epithelial cells from blood into cerebrospinal fluid (CSF). We used in vivo physiological measurements of transfer of endogenous (mouse) and exogenous (human) albumins, in situ Proximity Ligation Assay (in situ PLA), and qRT-PCR experiments to examine the cellular mechanism mediating protein transfer across the blood–CSF interface. We report that at all developmental stages mouse albumin and SPARC gave positive signals with in situ PLAs in plasma, CSF and within individual plexus cells suggesting a possible molecular interaction. In contrast, in situ PLA experiments in brain sections from mice injected with human albumin showed positive signals for human albumin in the vascular compartment that were only rarely identifiable within choroid plexus cells and only at older ages. Concentrations of both endogenous mouse albumin and exogenous (intraperitoneally injected) human albumin were estimated in plasma and CSF and expressed as CSF/plasma concentration ratios. Human albumin was not transferred through the mouse blood–CSF barrier to the same extent as endogenous mouse albumin, confirming results from in situ PLA. During postnatal development Sparc gene expression was higher in early postnatal ages than in the adult and changed in response to altered levels of albumin in blood plasma in a differential and developmentally regulated manner. Here we propose a possible cellular route and mechanism by which albumin is transferred from blood into CSF across a sub-population of specialised choroid plexus epithelial cells. PMID:25211495

αII Spectrin Forms a Periodic Cytoskeleton at the Axon Initial Segment and Is Required for Nervous System Function.

PubMed

Huang, Claire Yu-Mei; Zhang, Chuansheng; Ho, Tammy Szu-Yu; Oses-Prieto, Juan; Burlingame, Alma L; Lalonde, Joshua; Noebels, Jeffrey L; Leterrier, Christophe; Rasband, Matthew N

2017-11-22

Spectrins form a submembranous cytoskeleton proposed to confer strength and flexibility to neurons and to participate in ion channel clustering at axon initial segments (AIS) and nodes of Ranvier. Neuronal spectrin cytoskeletons consist of diverse β subunits and αII spectrin. Although αII spectrin is found in neurons in both axonal and somatodendritic domains, using proteomics, biochemistry, and superresolution microscopy, we show that αII and βIV spectrin interact and form a periodic AIS cytoskeleton. To determine the role of spectrins in the nervous system, we generated Sptan1 f/f mice for deletion of CNS αII spectrin. We analyzed αII spectrin-deficient mice of both sexes and found that loss of αII spectrin causes profound reductions in all β spectrins. αII spectrin-deficient mice die before 1 month of age and have disrupted AIS and many other neurological impairments including seizures, disrupted cortical lamination, and widespread neurodegeneration. These results demonstrate the importance of the spectrin cytoskeleton both at the AIS and throughout the nervous system. SIGNIFICANCE STATEMENT Spectrin cytoskeletons play diverse roles in neurons, including assembly of excitable domains such as the axon initial segment (AIS) and nodes of Ranvier. However, the molecular composition and structure of these cytoskeletons remain poorly understood. Here, we show that αII spectrin partners with βIV spectrin to form a periodic cytoskeleton at the AIS. Using a new αII spectrin conditional knock-out mouse, we show that αII spectrin is required for AIS assembly, neuronal excitability, cortical lamination, and to protect against neurodegeneration. These results demonstrate the broad importance of spectrin cytoskeletons for nervous system function and development and have important implications for nervous system injuries and diseases because disruption of the spectrin cytoskeleton is a common molecular pathology. Copyright © 2017 the authors 0270-6474/17/3711311-12$15.00/0.

FGF/FGFR Signaling Coordinates Skull Development by Modulating Magnitude of Morphological Integration: Evidence from Apert Syndrome Mouse Models

PubMed Central

Martínez-Abadías, Neus; Heuzé, Yann; Wang, Yingli; Jabs, Ethylin Wang; Aldridge, Kristina; Richtsmeier, Joan T.

2011-01-01

The fibroblast growth factor and receptor system (FGF/FGFR) mediates cell communication and pattern formation in many tissue types (e.g., osseous, nervous, vascular). In those craniosynostosis syndromes caused by FGFR1-3 mutations, alteration of signaling in the FGF/FGFR system leads to dysmorphology of the skull, brain and limbs, among other organs. Since this molecular pathway is widely expressed throughout head development, we explore whether and how two specific mutations on Fgfr2 causing Apert syndrome in humans affect the pattern and level of integration between the facial skeleton and the neurocranium using inbred Apert syndrome mouse models Fgfr2+/S252W and Fgfr2+/P253R and their non-mutant littermates at P0. Skull morphological integration (MI), which can reflect developmental interactions among traits by measuring the intensity of statistical associations among them, was assessed using data from microCT images of the skull of Apert syndrome mouse models and 3D geometric morphometric methods. Our results show that mutant Apert syndrome mice share the general pattern of MI with their non-mutant littermates, but the magnitude of integration between and within the facial skeleton and the neurocranium is increased, especially in Fgfr2+/S252W mice. This indicates that although Fgfr2 mutations do not disrupt skull MI, FGF/FGFR signaling is a covariance-generating process in skull development that acts as a global factor modulating the intensity of MI. As this pathway evolved early in vertebrate evolution, it may have played a significant role in establishing the patterns of skull MI and coordinating proper skull development. PMID:22053191

Hepatocyte Growth Factor and MET Support Mouse Enteric Nervous System Development, the Peristaltic Response, and Intestinal Epithelial Proliferation in Response to Injury

PubMed Central

Avetisyan, Marina; Wang, Hongtao; Schill, Ellen Merrick; Bery, Saya; Grider, John R.; Hassell, John A.; Stappenbeck, Thaddeus

2015-01-01

Factors providing trophic support to diverse enteric neuron subtypes remain poorly understood. We tested the hypothesis that hepatocyte growth factor (HGF) and the HGF receptor MET might support some types of enteric neurons. HGF and MET are expressed in fetal and adult enteric nervous system. In vitro, HGF increased enteric neuron differentiation and neurite length, but only if vanishingly small amounts (1 pg/ml) of glial cell line-derived neurotrophic factor were included in culture media. HGF effects were blocked by phosphatidylinositol-3 kinase inhibitor and by MET-blocking antibody. Both of these inhibitors and MEK inhibition reduced neurite length. In adult mice, MET was restricted to a subset of calcitonin gene-related peptide-immunoreactive (IR) myenteric plexus neurons thought to be intrinsic primary afferent neurons (IPANs). Conditional MET kinase domain inactivation (Metfl/fl; Wnt1Cre+) caused a dramatic loss of myenteric plexus MET-IR neurites and 1–1′-dioctodecyl-3,3,3′,3′-tetramethylindocarbocyamine perchlorate (DiI) labeling suggested reduced MET-IR neurite length. In vitro, Metfl/fl; Wnt1Cre+ mouse bowel had markedly reduced peristalsis in response to mucosal deformation, but normal response to radial muscle stretch. However, whole-bowel transit, small-bowel transit, and colonic-bead expulsion were normal in Metfl/fl; Wnt1Cre+ mice. Finally, Metfl/fl; Wnt1Cre+ mice had more bowel injury and reduced epithelial cell proliferation compared with WT animals after dextran sodium sulfate treatment. These results suggest that HGF/MET signaling is important for development and function of a subset IPANs and that these cells regulate intestinal motility and epithelial cell proliferation in response to bowel injury. SIGNIFICANCE STATEMENT The enteric nervous system has many neuronal subtypes that coordinate and control intestinal activity. Trophic factors that support these neuron types and enhance neurite growth after fetal development are not well understood. We show that a subset of adult calcitonin gene-related peptide (CGRP)-expressing myenteric neurons produce MET, the receptor for hepatocyte growth factor, and that loss of MET activity affects peristalsis in response to mucosal stroking, reduces MET-immunoreactive neurites, and increases susceptibility to dextran sodium sulfate-induced bowel injury. These observations may be relevant for understanding and treating intestinal motility disorders and also suggest that enhancing the activity of MET-expressing CGRP neurons might be a useful strategy to reduce bowel inflammation. PMID:26290232

Molecular and Physiological Characterization of Two Novel Multirepeat β-Thymosins from Silkworm, Bombyx mori

PubMed Central

Lü, Peng; Yang, Yanhua; Yao, Qin; Xia, Hengchuan; Chen, Keping

2015-01-01

β-thymosin plays important roles in the development of the lymphatic system and the central nervous system in vertebrates. However, its role and function in invertebrates remain much less explored. Here, we firstly isolated a gene encoding β-thymosin in silkworm (Bombyx mori L.). Interestingly, this gene encodes two polypeptides, named as BmTHY1 and BmTHY2, via two different modes of RNA splicing. The recombinant proteins fused with an N-term GST tag were over-expressed in Escherichia coli (E. coli) and further purified to near homogenity to prepare mouse antibodies. The Western blot analysis showed that these proteins were expressed in various tissues and organs, as well as in different developmental stages. Amazingly, the expression of BmTHY2 was hugely increased during the pupae stage, indicating a specialized role in this period. The expression of these proteins was gradually decreased in BmN cells infected by BmNPV, suggesting they may play different roles in the virus infection. In addition, both BmTHY1 and BmTHY2 can interact with 14-3-3 of silkworm and Ubiquitin of BmNPV as shown by GST pull down and Co-IP assays, consistent with their roles in the regulation of the development of nervous system. PMID:26474303

Generation and Nuclear Translocation of Sumoylated Transmembrane Fragment of Cell Adhesion Molecule L1

PubMed Central

Lutz, David; Wolters-Eisfeld, Gerrit; Joshi, Gunjan; Djogo, Nevena; Jakovcevski, Igor; Schachner, Melitta; Kleene, Ralf

2012-01-01

The functions of the cell adhesion molecule L1 in the developing and adult nervous system are triggered by homophilic and heterophilic interactions that stimulate signal transductions that activate cellular responses. Here, we show that stimulation of signaling by function-triggering L1 antibodies or L1-Fc leads to serine protease-dependent cleavage of full-length L1 at the plasma membrane and generation of a sumoylated transmembrane 70-kDa fragment comprising the intracellular and transmembrane domains and part of the extracellular domain. The 70-kDa transmembrane fragment is transported from the plasma membrane to a late endosomal compartment, released from endosomal membranes into the cytoplasm, and transferred from there into the nucleus by a pathway that depends on importin and chromatin-modifying protein 1. Mutation of the sumoylation site at Lys1172 or of the nuclear localization signal at Lys1147 abolished L1-stimulated generation or nuclear import of the 70-kDa fragment, respectively. Nuclear import of the 70-kDa fragment may activate cellular responses in parallel or in association with phosphorylation-dependent signaling pathways. Alterations in the levels of the 70-kDa fragment during development and in the adult after spinal cord injury or in a mouse model of Alzheimer disease suggest that this fragment is functionally implicated in development, regeneration, neurodegeneration, tumorigenesis, and possibly synaptic plasticity in the mature nervous system. PMID:22431726

Loss of visceral pain following colorectal distension in an endothelin-3 deficient mouse model of Hirschsprung's disease

PubMed Central

Zagorodnyuk, Vladimir P; Kyloh, Melinda; Nicholas, Sarah; Peiris, Heshan; Brookes, Simon J; Chen, Bao Nan; Spencer, Nick J

2011-01-01

Abstract Endothelin peptides and their endogenous receptors play a major role in nociception in a variety of different organs. They also play an essential role in the development of the enteric nervous system. Mice with deletions of the endothelin-3 gene (lethal spotted mice, ls/ls) develop congenital aganglionosis. However, little is known about how nociception might be affected in the aganglionic rectum of mice deficient in endothelin-3. In this study we investigated changes in spinal afferent innervation and visceral pain transmission from the aganglionic rectum in ls/ls mice. Electromyogram recordings from anaesthetized ls/ls mice revealed a deficit in visceromotor responses arising from the aganglionic colorectum in response to noxious colorectal distension. Loss of visceromotor responses (VMRs) in ls/ls mice was selective, as no reduction in VMRs was detected after stimulation of the bladder or somatic organs. Calcitonin gene related peptide (CGRP) immunoreactivity, retrograde neuronal tracing and extracellular afferent recordings from the aganglionic rectum revealed decreased colorectal spinal innervation, combined with a reduction in mechanosensitivity of rectal afferents. The sensory defect in ls/ls mice is primarily associated with changes in low threshold wide dynamic range rectal afferents. In conclusion, disruption of endothelin 3 gene expression not only affects development and function of the enteric nervous system, but also specific classes of spinal rectal mechanoreceptors, which are required for visceral nociception from the colorectum. PMID:21320883

Kalrn plays key roles within and outside of the nervous system.

PubMed

Mandela, Prashant; Yankova, Maya; Conti, Lisa H; Ma, Xin-Ming; Grady, James; Eipper, Betty A; Mains, Richard E

2012-11-01

The human KALRN gene, which encodes a complex, multifunctional Rho GDP/GTP exchange factor, has been linked to cardiovascular disease, psychiatric disorders and neurodegeneration. Examination of existing Kalrn knockout mouse models has focused only on neuronal phenotypes. However, Kalirin was first identified through its interaction with an enzyme involved in the synthesis and secretion of multiple bioactive peptides, and studies in C.elegans revealed roles for its orthologue in neurosecretion. We used a broad array of tests to evaluate the effects of ablating a single exon in the spectrin repeat region of Kalrn (KalSR(KO/KO)); transcripts encoding Kalrn isoforms containing only the second GEF domain can still be produced from the single remaining functional Kalrn promoter. As expected, KalSR(KO/KO) mice showed a decrease in anxiety-like behavior and a passive avoidance deficit. No changes were observed in prepulse inhibition of acoustic startle or tests of depression-like behavior. Growth rate, parturition and pituitary secretion of growth hormone and prolactin were deficient in the KalSR(KO/KO) mice. Based on the fact that a subset of Kalrn isoforms is expressed in mouse skeletal muscle and the observation that muscle function in C.elegans requires its Kalrn orthologue, KalSR(KO/KO) mice were evaluated in the rotarod and wire hang tests. KalSR(KO/KO) mice showed a profound decrease in neuromuscular function, with deficits apparent in KalSR(+/KO) mice; these deficits were not as marked when loss of Kalrn expression was restricted to the nervous system. Pre- and postsynaptic deficits in the neuromuscular junction were observed, along with alterations in sarcomere length. Many of the widespread and diverse deficits observed both within and outside of the nervous system when expression of Kalrn is eliminated may reflect its role in secretory granule function and its expression outside of the nervous system.

Kalrn plays key roles within and outside of the nervous system

PubMed Central

2012-01-01

Background The human KALRN gene, which encodes a complex, multifunctional Rho GDP/GTP exchange factor, has been linked to cardiovascular disease, psychiatric disorders and neurodegeneration. Examination of existing Kalrn knockout mouse models has focused only on neuronal phenotypes. However, Kalirin was first identified through its interaction with an enzyme involved in the synthesis and secretion of multiple bioactive peptides, and studies in C.elegans revealed roles for its orthologue in neurosecretion. Results We used a broad array of tests to evaluate the effects of ablating a single exon in the spectrin repeat region of Kalrn (KalSRKO/KO); transcripts encoding Kalrn isoforms containing only the second GEF domain can still be produced from the single remaining functional Kalrn promoter. As expected, KalSRKO/KO mice showed a decrease in anxiety-like behavior and a passive avoidance deficit. No changes were observed in prepulse inhibition of acoustic startle or tests of depression-like behavior. Growth rate, parturition and pituitary secretion of growth hormone and prolactin were deficient in the KalSRKO/KO mice. Based on the fact that a subset of Kalrn isoforms is expressed in mouse skeletal muscle and the observation that muscle function in C.elegans requires its Kalrn orthologue, KalSRKO/KO mice were evaluated in the rotarod and wire hang tests. KalSRKO/KO mice showed a profound decrease in neuromuscular function, with deficits apparent in KalSR+/KO mice; these deficits were not as marked when loss of Kalrn expression was restricted to the nervous system. Pre- and postsynaptic deficits in the neuromuscular junction were observed, along with alterations in sarcomere length. Conclusions Many of the widespread and diverse deficits observed both within and outside of the nervous system when expression of Kalrn is eliminated may reflect its role in secretory granule function and its expression outside of the nervous system. PMID:23116210

Spinal Cord Repair with Engineered Nervous Tissue

DTIC Science & Technology

2014-04-01

anti-SMI31 (1:1000, Covance ), mouse anti-SMI32 (1:1000, Covance ), chicken anti-Glial Fibrillary Acidic Protein (GFAP; 1:250, Millipore), rabbit anti...PRINCIPAL INVESTIGATOR: Douglas H. Smith, M.D. CONTRACTING ORGANIZATION : University of Pennsylvania Philadelphia PA 19104...PROJECT NUMBER 5e. TASK NUMBER Email: smithdou@mail.med.upenn.edu 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND

Effects of realgar on GSH synthesis in the mouse hippocampus: Involvement of system XAG(-), system XC(-), MRP-1 and Nrf2.

PubMed

Wang, Yanlei; Chen, Mo; Zhang, Yinghua; Huo, Taoguang; Fang, Ying; Jiao, Xuexin; Yuan, Mingmei; Jiang, Hong

2016-10-01

Realgar is a type of mineral drug that contains arsenic and has neurotoxicity. Glutathione (GSH), which is the main antioxidant in the central nervous system, plays a key role in antioxidant defenses and the detoxification of arsenic. However, whether realgar interferes with the synthesis of GSH in the brain and the molecular mechanisms underlying its effects are largely unknown. Here, we used mouse models of exposure to realgar to show that realgar affects the synthesis of GSH in the hippocampus, leading to ultrastructural changes in hippocampal neurons and synapses and deficiencies in cognitive abilities, and that the mechanisms that cause this effect may be associated with alterations in the expression of system XAG(-), system XC(-), multidrug resistance-associated protein 1(MRP-1), nuclear factor E2-related factor 2 (Nrf2), γ-glutamylcysteine synthetase (γ-GCS), and the levels of glutamate (Glu) and cysteine (Cys) in the extracellular fluid. These findings provide a theoretical basis for preventing the drug-induced chronic arsenic poisoning in the nervous system that is triggered by realgar. Copyright © 2016 Elsevier Inc. All rights reserved.

Role of connexin43 and ATP in long-range bystander radiation damage and oncogenesis in vivo.

PubMed

Mancuso, M; Pasquali, E; Leonardi, S; Rebessi, S; Tanori, M; Giardullo, P; Borra, F; Pazzaglia, S; Naus, C C; Di Majo, V; Saran, A

2011-11-10

Ionizing radiation is a genotoxic agent and human carcinogen. Recent work has questioned long-held dogmas by showing that cancer-associated genetic alterations occur in cells and tissues not directly exposed to radiation, questioning the robustness of the current system of radiation risk assessment. In vitro, diverse mechanisms involving secreted soluble factors, gap junction intercellular communication (GJIC) and oxidative metabolism are proposed to mediate these indirect effects. In vivo, the mechanisms behind long-range 'bystander' responses remain largely unknown. Here, we investigate the role of GJIC in propagating radiation stress signals in vivo, and in mediating radiation-associated bystander tumorigenesis in mouse central nervous system using a mouse model in which intercellular communication is downregulated by targeted deletion of the connexin43 (Cx43) gene. We show that GJIC is critical for transmission of oncogenic radiation damage to the non-targeted cerebellum, and that a mechanism involving adenosine triphosphate release and upregulation of Cx43, the major GJIC constituent, regulates transduction of oncogenic damage to unirradiated tissues in vivo. Our data provide a novel hypothesis for transduction of distant bystander effects and suggest that the highly branched nervous system, similar to the vascular network, has an important role.

Disturbed Processing of Contextual Information in HCN3 Channel Deficient Mice

PubMed Central

Stieglitz, Marc S.; Fenske, Stefanie; Hammelmann, Verena; Becirovic, Elvir; Schöttle, Verena; Delorme, James E.; Schöll-Weidinger, Martha; Mader, Robert; Deussing, Jan; Wolfer, David P.; Seeliger, Mathias W.; Albrecht, Urs; Wotjak, Carsten T.; Biel, Martin; Michalakis, Stylianos; Wahl-Schott, Christian

2018-01-01

Hyperpolarization-activated cyclic nucleotide-gated channels (HCNs) in the nervous system are implicated in a variety of neuronal functions including learning and memory, regulation of vigilance states and pain. Dysfunctions or genetic loss of these channels have been shown to cause human diseases such as epilepsy, depression, schizophrenia, and Parkinson's disease. The physiological functions of HCN1 and HCN2 channels in the nervous system have been analyzed using genetic knockout mouse models. By contrast, there are no such genetic studies for HCN3 channels so far. Here, we use a HCN3-deficient (HCN3−/−) mouse line, which has been previously generated in our group to examine the expression and function of this channel in the CNS. Specifically, we investigate the role of HCN3 channels for the regulation of circadian rhythm and for the determination of behavior. Contrary to previous suggestions we find that HCN3−/− mice show normal visual, photic, and non-photic circadian function. In addition, HCN3−/− mice are impaired in processing contextual information, which is characterized by attenuated long-term extinction of contextual fear and increased fear to a neutral context upon repeated exposure. PMID:29375299

A physiologically based pharmacokinetic model for atrazine and its main metabolites in the adult male C57BL/6 mouse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin Zhoumeng; Interdisciplinary Toxicology Program, University of Georgia, Athens, GA 30602; Fisher, Jeffrey W.

Atrazine (ATR) is a chlorotriazine herbicide that is widely used and relatively persistent in the environment. In laboratory rodents, excessive exposure to ATR is detrimental to the reproductive, immune, and nervous systems. To better understand the toxicokinetics of ATR and to fill the need for a mouse model, a physiologically based pharmacokinetic (PBPK) model for ATR and its main chlorotriazine metabolites (Cl-TRIs) desethyl atrazine (DE), desisopropyl atrazine (DIP), and didealkyl atrazine (DACT) was developed for the adult male C57BL/6 mouse. Taking advantage of all relevant and recently made available mouse-specific data, a flow-limited PBPK model was constructed. The ATR andmore » DACT sub-models included blood, brain, liver, kidney, richly and slowly perfused tissue compartments, as well as plasma protein binding and red blood cell binding, whereas the DE and DIP sub-models were constructed as simple five-compartment models. The model adequately simulated plasma levels of ATR and Cl-TRIs and urinary dosimetry of Cl-TRIs at four single oral dose levels (250, 125, 25, and 5 mg/kg). Additionally, the model adequately described the dose dependency of brain and liver ATR and DACT concentrations. Cumulative urinary DACT amounts were accurately predicted across a wide dose range, suggesting the model's potential use for extrapolation to human exposures by performing reverse dosimetry. The model was validated using previously reported data for plasma ATR and DACT in mice and rats. Overall, besides being the first mouse PBPK model for ATR and its Cl-TRIs, this model, by analogy, provides insights into tissue dosimetry for rats. The model could be used in tissue dosimetry prediction and as an aid in the exposure assessment to this widely used herbicide.« less

Gene Editing Vectors for Studying Nicotinic Acetylcholine Receptors in Cholinergic Transmission.

PubMed

Peng, Can; Yan, Yijin; Kim, Veronica J; Engle, Staci E; Berry, Jennifer N; McIntosh, J Michael; Neve, Rachael L; Drenan, Ryan M

2018-05-19

Nicotinic acetylcholine receptors (nAChRs), prototype members of the cys-loop ligand gated ion channel family, are key mediators of cholinergic transmission in the central nervous system. Despite their importance, technical gaps exist in our ability to dissect the function of individual subunits in the brain. To overcome these barriers, we designed CRISPR/Cas9 small guide RNA sequences (sgRNAs) for production of loss-of-function alleles in mouse nAChR genes. These sgRNAs were validated in vitro via deep sequencing. We subsequently targeted candidate nAChR genes in vivo by creating herpes simplex virus (HSV) vectors delivering sgRNAs and Cas9 expression to mouse brain. Production of loss-of-function insertions or deletions (indels) by these "all-in-one" HSV vectors was confirmed using brain slice patch clamp electrophysiology coupled with pharmacological analysis. Next, we developed a scheme for cell type-specific gene editing in mouse brain. Knockin mice expressing Cas9 in a Cre-dependent manner were validated using viral microinjections and genetic crosses to common Cre-driver mouse lines. We subsequently confirmed functional Cas9 activity by targeting the ubiquitous neuronal protein, NeuN, using adeno associated virus (AAV) delivery of sgRNAs. Finally, the mouse β2 nAChR gene was successfully targeted in dopamine transporter (DAT) positive neurons via CRISPR/Cas9. The sgRNA sequences and viral vectors, including our scheme for Cre-dependent gene editing, should be generally useful to the scientific research community. These tools could lead to new discoveries related to the function of nAChRs in neurotransmission and behavioral processes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Mitochondrial carbonic anhydrase in the nervous system: expression in neuronal and glial cells.

PubMed

Ghandour, M S; Parkkila, A K; Parkkila, S; Waheed, A; Sly, W S

2000-11-01

Carbonic anhydrase (CA) V is a mitochondrial enzyme that has been reported in several tissues of the gastrointestinal tract. In liver, it participates in ureagenesis and gluconeogenesis by providing bicarbonate ions for two other mitochondrial enzymes: carbamyl phosphate synthetase I and pyruvate carboxylase. This study presents evidence of immunohistochemical localization of CA V in the rodent nervous tissue. Polyclonal rabbit antisera against a polypeptide of 17 C-terminal amino acids of rat CA V and against purified recombinant mouse isozyme were used in western blotting and immunoperoxidase stainings. Immunohistochemistry showed that CA V is expressed in astrocytes and neurons but not in oligodendrocytes, which are rich in CA II, or capillary endothelial cells, which express CA IV on their plasma face. The specificity of the immunohistochemical results was confirmed by western blotting, which identified a major 30-kDa polypeptide band of CA V in mouse cerebral cortex, hippocampus, cerebellum, spinal cord, and sciatic nerve. The expression of CA V in astrocytes and neurons suggests that this isozyme has a cell-specific, physiological role in the nervous system. In astrocytes, CA V may play an important role in gluconeogenesis by providing bicarbonate ions for the pyruvate carboxylase. The neuronal CA V could be involved in the regulation of the intramitochondrial calcium level, thus contributing to the stability of the intracellular calcium concentration. CA V may also participate in bicarbonate ion-induced GABA responses by regulating the bicarbonate homeostasis in neurons, and its inhibition could be the basis of some neurotropic effects of carbonic anhydrase inhibitors.

Control of the collective migration of enteric neural crest cells by the Complement anaphylatoxin C3a and N-cadherin

PubMed Central

Broders-Bondon, Florence; Paul-Gilloteaux, Perrine; Gazquez, Elodie; Heysch, Julie; Piel, Matthieu; Mayor, Roberto; Lambris, John D.; Dufour, Sylvie

2016-01-01

We analyzed the cellular and molecular mechanisms governing the adhesive and migratory behavior of enteric neural crest cells (ENCCs) during their collective migration within the developing mouse gut. We aimed to decipher the role of the complement anaphylatoxin C3a during this process, because this well-known immune system attractant has been implicated in cephalic NCC co-attraction, a process controlling directional migration. We used the conditional Ht-PA-cre transgenic mouse model allowing a specific ablation of the N-cadherin gene and the expression of a fluorescent reporter in migratory ENCCs without affecting the central nervous system. We performed time-lapse videomicroscopy of ENCCs from control and N-cad-herin mutant gut explants cultured on fibronectin (FN) and micropatterned FN-stripes with C3a or C3aR antagonist, and studied cell migration behavior with the use of triangulation analysis to quantify cell dispersion. We performed ex vivo gut cultures with or without C3aR antagonist to determine the effect on ENCC behavior. Confocal microscopy was used to analyze the cell-matrix adhesion properties. We provide the first demonstration of the localization of the complement anaphylatoxin C3a and its receptor on ENCCs during their migration in the embryonic gut. C3aR receptor inhibition alters ENCC adhesion and migration, perturbing directionality and increasing cell dispersion both in vitro and ex vivo. N-cad-herin-null ENCCs do not respond to C3a co-attraction. These findings indicate that C3a regulates cell migration in a N-cadherin-dependent process. Our results shed light on the role of C3a in regulating collective and directional cell migration, and in ganglia network organization during enteric nervous system ontogenesis. The detection of an immune system chemokine in ENCCs during ENS development may also shed light on new mechanisms for gastrointestinal disorders. PMID:27041467

A novel histochemical method for the visualization of thrombin activity in the nervous system.

PubMed

Bushi, D; Gera, O; Kostenich, G; Shavit-Stein, E; Weiss, R; Chapman, J; Tanne, D

2016-04-21

Although thrombin has an important role in both central and peripheral nerve diseases, characterization of the anatomical distribution of its proteolytic activity has been limited by available methods. This study presents the development, challenges, validation and implementation of a novel histochemical method for visualization of thrombin activity in the nervous system. The method is based on the cleavage of the substrate, Boc-Asp(OBzl)-Pro-Arg-4MβNA by thrombin to liberate free 4-methoxy-2-naphthylamine (4MβNA). In the presence of 5-nitrosalicylaldehyde, free 4MβNA is captured, yielding an insoluble yellow fluorescent precipitate which marks the site of thrombin activity. The sensitivity of the method was determined in vitro using known concentrations of thrombin while the specificity was verified using a highly specific thrombin inhibitor. Using this method we determined the spatial distribution of thrombin activity in mouse brain following transient middle cerebral artery occlusion (tMCAo) and in mouse sciatic nerve following crush injury. Fluorescence microscopy revealed well-defined thrombin activity localized to the right ischemic hemisphere in cortical areas and in the striatum compared to negligible thrombin activity contralaterally. The histochemical localization of thrombin activity following tMCAo was in good correlation with the infarct areas per triphenyltetrazolium chloride staining and to thrombin activity measured biochemically in tissue punches (85 ± 35 and 20 ± 3 mU/ml, in the cortical and striatum areas respectively, compared to 7 ± 2 and 13 ± 2 mU/ml, in the corresponding contralateral areas; mean ± SEM; p<0.05). In addition, 24 h following crush injury, focal areas of highly elevated thrombin activity were detected in teased sciatic fibers. This observation was supported by the biochemical assay and western blot technique. The histochemical method developed in this study can serve as an important tool for studying the role of thrombin in physiological and pathological conditions. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Death receptors DR6 and TROY regulate brain vascular development.

PubMed

Tam, Stephen J; Richmond, David L; Kaminker, Joshua S; Modrusan, Zora; Martin-McNulty, Baby; Cao, Tim C; Weimer, Robby M; Carano, Richard A D; van Bruggen, Nick; Watts, Ryan J

2012-02-14

Signaling events that regulate central nervous system (CNS) angiogenesis and blood-brain barrier (BBB) formation are only beginning to be elucidated. By evaluating the gene expression profile of mouse vasculature, we identified DR6/TNFRSF21 and TROY/TNFRSF19 as regulators of CNS-specific angiogenesis in both zebrafish and mice. Furthermore, these two death receptors interact both genetically and physically and are required for vascular endothelial growth factor (VEGF)-mediated JNK activation and subsequent human brain endothelial sprouting in vitro. Increasing beta-catenin levels in brain endothelium upregulate DR6 and TROY, indicating that these death receptors are downstream target genes of Wnt/beta-catenin signaling, which has been shown to be required for BBB development. These findings define a role for death receptors DR6 and TROY in CNS-specific vascular development. Copyright © 2012 Elsevier Inc. All rights reserved.

Role of the Cellular Prion Protein in Oligodendrocyte Precursor Cell Proliferation and Differentiation in the Developing and Adult Mouse CNS

PubMed Central

Bribián, Ana; Gavín, Rosalina; Reina, Manuel; García-Verdugo, José Manuel; Torres, Juan María; de Castro, Fernando; del Río, José Antonio

2012-01-01

There are numerous studies describing the signaling mechanisms that mediate oligodendrocyte precursor cell (OPC) proliferation and differentiation, although the contribution of the cellular prion protein (PrPc) to this process remains unclear. PrPc is a glycosyl-phosphatidylinositol (GPI)-anchored glycoprotein involved in diverse cellular processes during the development and maturation of the mammalian central nervous system (CNS). Here we describe how PrPc influences oligodendrocyte proliferation in the developing and adult CNS. OPCs that lack PrPc proliferate more vigorously at the expense of a delay in differentiation, which correlates with changes in the expression of oligodendrocyte lineage markers. In addition, numerous NG2-positive cells were observed in cortical regions of adult PrPc knockout mice, although no significant changes in myelination can be seen, probably due to the death of surplus cells. PMID:22529900

FGF2 deficit during development leads to specific neuronal cell loss in the enteric nervous system.

PubMed

Hagl, Cornelia Irene; Wink, Elvira; Scherf, Sabrina; Heumüller-Klug, Sabine; Hausott, Barbara; Schäfer, Karl-Herbert

2013-01-01

The largest part of the peripheral nervous system is the enteric nervous system (ENS). It consists of an intricate network of several enteric neuronal subclasses with distinct phenotypes and functions within the gut wall. The generation of these enteric phenotypes is dependent upon appropriate neurotrophic support during development. Glial cell line-derived neurotrophic factor (GDNF) and fibroblast growth factor-2 (FGF2) play an important role in the differentiation and function of the ENS. A lack of GDNF or its receptor (Ret) causes intestinal aganglionosis in mice, while fibroblast growth factor receptor signaling antagonist is identified as regulating proteins in the GDNF/Ret signaling in the developing ENS. Primary myenteric plexus cultures and wholemount preparations of wild type (WT) and FGF2-knockout mice were used to analyze distinct enteric subpopulations. Fractal dimension (D) as a measure of self-similarity is an excellent tool to analyze complex geometric shape and was applied to classify the subclasses of enteric neurons concerning their individual morphology. As a consequence of a detailed analysis of subpopulation variations, wholemount preparations were stained for the calcium binding proteins calbindin and calretinin. The fractal analysis showed a reliable consistence of subgroups with different fractal dimensions (D) in each culture investigated. Seven different neuronal subtypes could be differentiated according to a rising D. Within the same D, the neurite length revealed significant differences between wild type and FGF2-knockout cultures, while the subclass distribution was also altered. Depending on the morphological characteristics, the reduced subgroup was supposed to be a secretomotor neuronal type, which could be confirmed by calbindin and calretinin staining of the wholemount preparations. These revealed a reduction up to 40 % of calbindin-positive neurons in the FGF2-knockout mouse. We therefore consider FGF2 playing a more important role in the fine-tuning of the ENS during development as previously assumed.

Differential expression of growth factors at the cellular level in virus-infected brain

PubMed Central

Prosniak, Mikhail; Zborek, Anna; Scott, Gwen S.; Roy, Anirban; Phares, Timothy W.; Koprowski, Hilary; Hooper, D. Craig

2003-01-01

The contribution of host factors to rabies virus (RV) transcription/replication and axonal/transsynaptic spread is largely unknown. We previously identified several host genes that are up-regulated in the mouse brain during RV infection, including neuroleukin, which is involved in neuronal growth and survival, cell motility, and differentiation, and fibroblast growth factor homologous factor 4 (FHF4), which has been implicated in limb and nervous system development. In this study, we used real-time quantitative RT-PCR to assess the expression of mRNAs specific for neuroleukin, the two isoforms of FHF4 (FHF4-1a and -1b) encoded by the FHF4 gene, and N protein of RV in neurons and astrocytes isolated by laser capture microdissection from mouse brains infected with the laboratory-adapted RV strain CVS-N2c or with a street RV of silver-haired bat origin. Differences in the gene expression patterns suggest that the capacity of RV strains to infect nonneuronal cells and differentially modulate host gene expression may be important in virus replication and spread in the CNS. PMID:12736376

Mouse Mesenchyme forkhead 2 (Mf2): expression, DNA binding and induction by sonic hedgehog during somitogenesis.

PubMed

Wu, S C; Grindley, J; Winnier, G E; Hargett, L; Hogan, B L

1998-01-01

Cloning and sequencing of mouse Mf2 (mesoderm/mesenchyme forkhead 2) cDNAs revealed an open reading frame encoding a putative protein of 492 amino acids which, after in vitro translation, binds to a DNA consensus sequence. Mf2 is expressed at high levels in the ventral region of newly formed somites, in sclerotomal derivatives, in lateral plate and cephalic mesoderm and in the first and second branchial arches. Other regions of mesodermal expression include the developing tongue, meninges, nose, whiskers, kidney, genital tubercule and limb joints. In the nervous system Mf2 is transcribed in restricted regions of the mid- and forebrain. In several tissues, including the early somite, Mf2 is expressed in cell populations adjacent to regions expressing sonic hedgehog (Shh) and in explant cultures of presomitic mesoderm Mf2 is induced by Shh secreted by COS cells. These results suggest that Mf2, like other murine forkhead genes, has multiple roles in embryogenesis, possibly mediating the response of cells to signaling molecules such as SHH.

Convection Enhanced Delivery of Recombinant Adeno-associated Virus into the Mouse Brain.

PubMed

Nash, Kevin R; Gordon, Marcia N

2016-01-01

Recombinant adeno-associated virus (rAAV) has become an extremely useful tool for the study of gene over expression or knockdown in the central nervous system of experimental animals. One disadvantage of intracranial injections of rAAV vectors into the brain parenchyma has been restricted distribution to relatively small volumes of the brain. Convection enhanced delivery (CED) is a method for delivery of clinically relevant amounts of therapeutic agents to large areas of the brain in a direct intracranial injection procedure. CED uses bulk flow to increase the hydrostatic pressure and thus improve volume distribution. The CED method has shown robust gene transfer and increased distribution within the CNS and can be successfully used for different serotypes of rAAV for increased transduction of the mouse CNS. This chapter details the surgical injection of rAAV by CED into a mouse brain.

Developmental abnormalities and age-related neurodegeneration in a mouse model of Down syndrome

PubMed Central

Holtzman, David M.; Santucci, Daniela; Kilbridge, Joshua; Chua-Couzens, Jane; Fontana, David J.; Daniels, Scott E.; Johnson, Randolph M.; Chen, Karen; Sun, Yuling; Carlson, Elaine; Alleva, Enrico; Epstein, Charles J.; Mobley, William C.

1996-01-01

To study the pathogenesis of central nervous system abnormalities in Down syndrome (DS), we have analyzed a new genetic model of DS, the partial trisomy 16 (Ts65Dn) mouse. Ts65Dn mice have an extra copy of the distal aspect of mouse chromosome 16, a segment homologous to human chromosome 21 that contains much of the genetic material responsible for the DS phenotype. Ts65Dn mice show developmental delay during the postnatal period as well as abnormal behaviors in both young and adult animals that may be analogous to mental retardation. Though the Ts65Dn brain is normal on gross examination, there is age-related degeneration of septohippocampal cholinergic neurons and astrocytic hypertrophy, markers of the Alzheimer disease pathology that is present in elderly DS individuals. These findings suggest that Ts65Dn mice may be used to study certain developmental and degenerative abnormalities in the DS brain. PMID:8917591

Detection of herpes simplex virus-specific DNA sequences in latently infected mice and in humans.

PubMed

Efstathiou, S; Minson, A C; Field, H J; Anderson, J R; Wildy, P

1986-02-01

Herpes simplex virus-specific DNA sequences have been detected by Southern hybridization analysis in both central and peripheral nervous system tissues of latently infected mice. We have detected virus-specific sequences corresponding to the junction fragment but not the genomic termini, an observation first made by Rock and Fraser (Nature [London] 302:523-525, 1983). This "endless" herpes simplex virus DNA is both qualitatively and quantitatively stable in mouse neural tissue analyzed over a 4-month period. In addition, examination of DNA extracted from human trigeminal ganglia has shown herpes simplex virus DNA to be present in an "endless" form similar to that found in the mouse model system. Further restriction enzyme analysis of latently infected mouse brainstem and human trigeminal DNA has shown that this "endless" herpes simplex virus DNA is present in all four isomeric configurations.

Detection of herpes simplex virus-specific DNA sequences in latently infected mice and in humans.

PubMed Central

Efstathiou, S; Minson, A C; Field, H J; Anderson, J R; Wildy, P

1986-01-01

Herpes simplex virus-specific DNA sequences have been detected by Southern hybridization analysis in both central and peripheral nervous system tissues of latently infected mice. We have detected virus-specific sequences corresponding to the junction fragment but not the genomic termini, an observation first made by Rock and Fraser (Nature [London] 302:523-525, 1983). This "endless" herpes simplex virus DNA is both qualitatively and quantitatively stable in mouse neural tissue analyzed over a 4-month period. In addition, examination of DNA extracted from human trigeminal ganglia has shown herpes simplex virus DNA to be present in an "endless" form similar to that found in the mouse model system. Further restriction enzyme analysis of latently infected mouse brainstem and human trigeminal DNA has shown that this "endless" herpes simplex virus DNA is present in all four isomeric configurations. Images PMID:3003377

From Cloning Neural Development Genes to Functional Studies in Mice, 30 Years of Advancements.

PubMed

Joyner, Alexandra L

2016-01-01

The invention of new mouse molecular genetics techniques, initiated in the 1980s, has repeatedly expanded our ability to tackle exciting developmental biology problems. The brain is the most complex organ, and as such the more sophisticated the molecular genetics technique, the more impact they have on uncovering new insights into how our brain functions. I provide a general time line for the introduction of new techniques over the past 30 years and give examples of new discoveries in the neural development field that emanated from them. I include a look to what the future holds and argue that we are at the dawn of a very exciting age for young scientists interested in studying how the nervous system is constructed and functions with such precision. © 2016 Elsevier Inc. All rights reserved.

Localization of PPAR isotypes in the adult mouse and human brain

PubMed Central

Warden, Anna; Truitt, Jay; Merriman, Morgan; Ponomareva, Olga; Jameson, Kelly; Ferguson, Laura B.; Mayfield, R. Dayne; Harris, R. Adron

2016-01-01

Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that act as ligand-activated transcription factors. PPAR agonists have well-documented anti-inflammatory and neuroprotective roles in the central nervous system. Recent evidence suggests that PPAR agonists are attractive therapeutic agents for treating neurodegenerative diseases as well as addiction. However, the distribution of PPAR mRNA and protein in brain regions associated with these conditions (i.e. prefrontal cortex, nucleus accumbens, amygdala, ventral tegmental area) is not well defined. Moreover, the cell type specificity of PPARs in mouse and human brain tissue has yet to be investigated. We utilized quantitative PCR and double immunofluorescence microscopy to determine that both PPAR mRNA and protein are expressed ubiquitously throughout the adult mouse brain. We found that PPARs have unique cell type specificities that are consistent between species. PPARα was the only isotype to colocalize with all cell types in both adult mouse and adult human brain tissue. Overall, we observed a strong neuronal signature, which raises the possibility that PPAR agonists may be targeting neurons rather than glia to produce neuroprotection. Our results fill critical gaps in PPAR distribution and define novel cell type specificity profiles in the adult mouse and human brain. PMID:27283430

Localization of PPAR isotypes in the adult mouse and human brain.

PubMed

Warden, Anna; Truitt, Jay; Merriman, Morgan; Ponomareva, Olga; Jameson, Kelly; Ferguson, Laura B; Mayfield, R Dayne; Harris, R Adron

2016-06-10

Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that act as ligand-activated transcription factors. PPAR agonists have well-documented anti-inflammatory and neuroprotective roles in the central nervous system. Recent evidence suggests that PPAR agonists are attractive therapeutic agents for treating neurodegenerative diseases as well as addiction. However, the distribution of PPAR mRNA and protein in brain regions associated with these conditions (i.e. prefrontal cortex, nucleus accumbens, amygdala, ventral tegmental area) is not well defined. Moreover, the cell type specificity of PPARs in mouse and human brain tissue has yet to be investigated. We utilized quantitative PCR and double immunofluorescence microscopy to determine that both PPAR mRNA and protein are expressed ubiquitously throughout the adult mouse brain. We found that PPARs have unique cell type specificities that are consistent between species. PPARα was the only isotype to colocalize with all cell types in both adult mouse and adult human brain tissue. Overall, we observed a strong neuronal signature, which raises the possibility that PPAR agonists may be targeting neurons rather than glia to produce neuroprotection. Our results fill critical gaps in PPAR distribution and define novel cell type specificity profiles in the adult mouse and human brain.

CCL11 promotes migration and proliferation of mouse neural progenitor cells.

PubMed

Wang, Feifei; Baba, Nobuyasu; Shen, Yuan; Yamashita, Tatsuyuki; Tsuru, Emi; Tsuda, Masayuki; Maeda, Nagamasa; Sagara, Yusuke

2017-02-07

Neonatal hypoxia-ischemia induces massive brain damage during the perinatal period, resulting in long-term consequences to central nervous system structural and functional maturation. Although neural progenitor cells (NPCs) migrate through the parenchyma and home in to injury sites in the rodent brain, the molecular mechanisms are unknown. We examined the role of chemokines in mediating NPC migration after neonatal hypoxic-ischemic brain injury. Nine-day-old mice were exposed to a 120-minute hypoxia following unilateral carotid occlusion. Chemokine levels were quantified in mouse brain extract. Migration and proliferation assays were performed using embryonic and infant mouse NPCs. The neonatal hypoxic-ischemic brain injury resulted in an ipsilateral lesion, which was extended to the cortical and striatal areas. NPCs migrated toward an injured area, where a marked increase of CC chemokines was detected. In vitro studies showed that incubation of NPCs with recombinant mouse CCL11 promoted migration and proliferation. These effects were partly inhibited by a CCR3 antagonist, SB297006. Our data implicate an important effect of CCL11 for mouse NPCs. The effective activation of NPCs may offer a promising strategy for neuroregeneration in neonatal hypoxic-ischemic brain injury.

The RNA-binding protein Musashi-1 is produced in the developing and adult mouse eye.

PubMed

Raji, B; Dansault, A; Leemput, J; de la Houssaye, G; Vieira, V; Kobetz, A; Arbogast, L; Masson, C; Menasche, M; Abitbol, M

2007-08-10

Musashi-1 (Msi1) is an RNA-binding protein produced in various types of stem cells including neural stem/progenitor cells and astroglial progenitor cells in the vertebrate central nervous system. Other RNA-binding proteins such as Pumilio-1, Pumilio-2, Staufen-1, and Staufen-2 have been characterized as potential markers of several types of stem or progenitor cells. We investigated the involvement of Msi1 in mouse eye development and adult mouse eye functions by analyzing the profile of Msi1 production in all ocular structures during development and adulthood. We studied Msi1 production by in situ hybridization and immunohistochemistry of ocular tissue sections and by semi-quantitative RT-PCR and western blot analysis from the embryonic stage of 12.5 days post coitum (E12.5 dpc) when the first retinal ganglion cells (RGCs) begin to appear to the adult stage when all retinal cell types are present. Msi1 mRNA was present at all studied stages of eye development. Msi1 protein was detected in the primitive neuroblastic layer (NbL), the ganglion cell layer (GCL), and in all major differentiated neurons of postnatal developing and adult retinae. During postnatal developing stages, faint diffuse Msi1 protein staining is converted to a more specific distribution once mouse retina is fully differentiated. The most striking result of our study concerns the large amounts of Msi1 protein and mRNA in several unexpected sites of adult mouse eyes including the corneal epithelium and endothelium, stromal keratocytes, progenitor cells of the limbus, equatorial lens stem cells, differentiated lens epithelial cells, and differentiating lens fibers. Msi1 was also found in the pigmented and nonpigmented cells of the ciliary processes, the melanocytes of the ciliary body, the retinal pigment epithelium, differentiated retinal neurons, and most probably in the retinal glial cells such as Müller glial cells, astrocytes, and the oligodendocytes surrounding the axons of the optic nerve. Msi1 expression was detected in the outer plexiform layer, the inner plexiform layer, and the nerve fiber layer of fully differentiated adult retina. We provide here the first demonstration that the RNA-binding protein, Msi1, is produced in mouse eyes from embryonic stages until adulthood. The relationship between the presence of Msi1 in developing ocular compartments and the possible stem/progenitor cell characteristics of these compartments remains unclear. Finally, the expression of Msi1 in several different cell types in the adult eye is extremely intriguing and should lead to further attempts to unravel the role of Msi1 in cellular and subcellular RNA metabolism and in the control of translational processes in adult eye cells particularly in adult neuronal dendrites, axons, and synapses.

RNA content in motor and sensory neurons and surrounding neuroglia of mouse spinal cord under conditions of hypodynamia and following normalization

NASA Technical Reports Server (NTRS)

Brumberg, V. A.; Pevzner, L. A.

1980-01-01

The differences in the dynamics of reparative processes in RNA metabolism within the neuron-neuroglia unit after the cessation of hyper- and hypodynamia is dicussed. The role of neuroglia is stressed in compensatory, reparative and trophic processes in the nervous system as well as the possibility in an adaptation at the cellular level.

Expression of the mouse Macf2 gene during inner ear development.

PubMed

Leonova, Elena V; Lomax, Margaret I

2002-09-30

Plakins, a family of linker proteins that connect cytoskeletal elements to cellular junctions and the extracellular matrix, are primarily responsible for the mechanical properties of cells and tissues. They include desmoplakin, envoplakin, plectin, dystonin/BPAG1, and Kakapo. Mutations in plakins cause several skin, muscular and neurological disorders. Macrophins are a recently discovered subfamily of plakins with binding domains for actin, intermediate filaments and microtubules. Characteristic features of macrophins include variable actin binding domains, a central rod domain containing both plectin and spectrin repeats, and a C-terminus containing EF hands and GAS2/GAR22 domain. We have examined expression of mouse Macf2, encoding macrophin-2, in adult tissues and in the developing, neonatal, and mature inner ear by in situ hybridization. Northern blot analysis identified three large tissue-specific Macf2 transcripts: a 16-kb mRNA in skeletal muscle and heart, a 15-kb mRNA in brain, and a 9-kb mRNA in RNA from ovary plus uterus. In situ hybridization of the developing mouse inner ear indicated that Macf2 is expressed in the otocyst at day 12.5, in the sensory epithelium by embryonic day 16.5, and in both inner and outer hair cells by day 16.5. Macf2 is expressed in the bodies of both sensory and motor neurons in the central and peripheral nervous system, including the auditory pathway. The Macf2 protein could be involved in the regulation of cytoskeletal connections to cellular junctions and play an important structural role in organs, such as the inner ear, that are subjected to strong mechanical forces. Copyright 2002 Elsevier Science B.V.

Transcriptional profiling reveals that C5a alters microRNA in brain endothelial cells

PubMed Central

Eadon, Michael T; Jacob, Alexander; Cunningham, Patrick N; Quigg, Richard J; Garcia, Joe G N; Alexander, Jessy J

2014-01-01

Blood–brain barrier (BBB) disturbance is a crucial occurrence in many neurological diseases, including systemic lupus erythematosus (SLE). Our previous studies showed that experimental lupus serum altered the integrity of the mouse brain endothelial layer, an important constituent of the BBB. Complement activation occurs in lupus with increased circulating complement components. Using a genomics approach, we identified the microRNA (miRNA) altered in mouse brain endothelial cells (bEnd3) by lupus serum and the complement protein, C5a. Of the 318 miRNA evaluated, 23 miRNAs were altered by lupus serum and 32 were altered by C5a alone compared with controls. Seven miRNAs (P < 0·05) were differentially expressed by both treatments: mmu-miR-133a*, mmu-miR-193*, mmu-miR-26b, mmu-miR-28*, mmu-miR-320a, mmu-miR-423-3p and mmu-miR-509-5p. The microarray results were validated by quantitative RT-PCR. In line with the in vitro results, expression of miR-26b and miR-28* were also significantly up-regulated in lupus mouse brain which was reduced by C5a receptor inhibition. Target prediction analysis revealed miR gene targets encoding components involved in inflammation, matrix arrangement, and apoptosis, pathways known to play important roles in central nervous system lupus. Our findings suggest that the miRNAs reported in this study may represent novel therapeutic targets in central nervous system lupus and other similar neuroinflammatory settings. PMID:24801999

Transcriptional profiling reveals that C5a alters microRNA in brain endothelial cells.

PubMed

Eadon, Michael T; Jacob, Alexander; Cunningham, Patrick N; Quigg, Richard J; Garcia, Joe G N; Alexander, Jessy J

2014-11-01

Blood-brain barrier (BBB) disturbance is a crucial occurrence in many neurological diseases, including systemic lupus erythematosus (SLE). Our previous studies showed that experimental lupus serum altered the integrity of the mouse brain endothelial layer, an important constituent of the BBB. Complement activation occurs in lupus with increased circulating complement components. Using a genomics approach, we identified the microRNA (miRNA) altered in mouse brain endothelial cells (bEnd3) by lupus serum and the complement protein, C5a. Of the 318 miRNA evaluated, 23 miRNAs were altered by lupus serum and 32 were altered by C5a alone compared with controls. Seven miRNAs (P < 0 · 05) were differentially expressed by both treatments: mmu-miR-133a*, mmu-miR-193*, mmu-miR-26b, mmu-miR-28*, mmu-miR-320a, mmu-miR-423-3p and mmu-miR-509-5p. The microarray results were validated by quantitative RT-PCR. In line with the in vitro results, expression of miR-26b and miR-28* were also significantly up-regulated in lupus mouse brain which was reduced by C5a receptor inhibition. Target prediction analysis revealed miR gene targets encoding components involved in inflammation, matrix arrangement, and apoptosis, pathways known to play important roles in central nervous system lupus. Our findings suggest that the miRNAs reported in this study may represent novel therapeutic targets in central nervous system lupus and other similar neuroinflammatory settings. © 2014 John Wiley & Sons Ltd.

A role for myelin-associated peroxisomes in maintaining paranodal loops and axonal integrity.

PubMed

Kassmann, Celia M; Quintes, Susanne; Rietdorf, Jens; Möbius, Wiebke; Sereda, Michael Werner; Nientiedt, Tobias; Saher, Gesine; Baes, Myriam; Nave, Klaus-Armin

2011-07-21

Demyelinating diseases of the nervous system cause axon loss but the underlying mechanisms are not well understood. Here we show by confocal and electron microscopy that in myelin-forming glia peroxisomes are associated with myelin membranes. When peroxisome biogenesis is experimentally perturbed in Pex5 conditional mouse mutants, myelination by Schwann cells appears initially normal. However, in nerves of older mice paranodal loops become physically unstable and develop swellings filled with vesicles and electron-dense material. This novel model of a demyelinating neuropathy demonstrates that peroxisomes serve an important function in the peripheral myelin compartment, required for long-term axonal integrity. Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

A Mouse Model for Conditional Secretion of Specific Single-Chain Antibodies Provides Genetic Evidence for Regulation of Cortical Plasticity by a Non-cell Autonomous Homeoprotein Transcription Factor.

PubMed

Bernard, Clémence; Vincent, Clémentine; Testa, Damien; Bertini, Eva; Ribot, Jérôme; Di Nardo, Ariel A; Volovitch, Michel; Prochiantz, Alain

2016-05-01

During postnatal life the cerebral cortex passes through critical periods of plasticity allowing its physiological adaptation to the environment. In the visual cortex, critical period onset and closure are influenced by the non-cell autonomous activity of the Otx2 homeoprotein transcription factor, which regulates the maturation of parvalbumin-expressing inhibitory interneurons (PV cells). In adult mice, the maintenance of a non-plastic adult state requires continuous Otx2 import by PV cells. An important source of extra-cortical Otx2 is the choroid plexus, which secretes Otx2 into the cerebrospinal fluid. Otx2 secretion and internalization requires two small peptidic domains that are part of the DNA-binding domain. Thus, mutating these "transfer" sequences also modifies cell autonomous transcription, precluding this approach to obtain a cell autonomous-only mouse. Here, we develop a mouse model with inducible secretion of an anti-Otx2 single-chain antibody to trap Otx2 in the extracellular milieu. Postnatal secretion of this single-chain antibody by PV cells delays PV maturation and reduces plasticity gene expression. Induced adult expression of this single-chain antibody in cerebrospinal fluid decreases Otx2 internalization by PV cells, strongly induces plasticity gene expression and reopens physiological plasticity. We provide the first mammalian genetic evidence for a signaling mechanism involving intercellular transfer of a homeoprotein transcription factor. Our single-chain antibody mouse model is a valid strategy for extracellular neutralization that could be applied to other homeoproteins and signaling molecules within and beyond the nervous system.

Mutation of the Diamond-Blackfan Anemia Gene Rps7 in Mouse Results in Morphological and Neuroanatomical Phenotypes

PubMed Central

Watkins-Chow, Dawn E.; Cooke, Joanna; Pidsley, Ruth; Edwards, Andrew; Slotkin, Rebecca; Leeds, Karen E.; Mullen, Raymond; Baxter, Laura L.; Campbell, Thomas G.; Salzer, Marion C.; Biondini, Laura; Gibney, Gretchen; Phan Dinh Tuy, Françoise; Chelly, Jamel; Morris, H. Douglas; Riegler, Johannes; Lythgoe, Mark F.; Arkell, Ruth M.; Loreni, Fabrizio; Flint, Jonathan

2013-01-01

The ribosome is an evolutionarily conserved organelle essential for cellular function. Ribosome construction requires assembly of approximately 80 different ribosomal proteins (RPs) and four different species of rRNA. As RPs co-assemble into one multi-subunit complex, mutation of the genes that encode RPs might be expected to give rise to phenocopies, in which the same phenotype is associated with loss-of-function of each individual gene. However, a more complex picture is emerging in which, in addition to a group of shared phenotypes, diverse RP gene-specific phenotypes are observed. Here we report the first two mouse mutations (Rps7Mtu and Rps7Zma) of ribosomal protein S7 (Rps7), a gene that has been implicated in Diamond-Blackfan anemia. Rps7 disruption results in decreased body size, abnormal skeletal morphology, mid-ventral white spotting, and eye malformations. These phenotypes are reported in other murine RP mutants and, as demonstrated for some other RP mutations, are ameliorated by Trp53 deficiency. Interestingly, Rps7 mutants have additional overt malformations of the developing central nervous system and deficits in working memory, phenotypes that are not reported in murine or human RP gene mutants. Conversely, Rps7 mouse mutants show no anemia or hyperpigmentation, phenotypes associated with mutation of human RPS7 and other murine RPs, respectively. We provide two novel RP mouse models and expand the repertoire of potential phenotypes that should be examined in RP mutants to further explore the concept of RP gene-specific phenotypes. PMID:23382688

The transgenic expression of LARGE exacerbates the muscle phenotype of dystroglycanopathy mice.

PubMed

Whitmore, Charlotte; Fernandez-Fuente, Marta; Booler, Helen; Parr, Callum; Kavishwar, Manoli; Ashraf, Attia; Lacey, Erica; Kim, Jihee; Terry, Rebecca; Ackroyd, Mark R; Wells, Kim E; Muntoni, Francesco; Wells, Dominic J; Brown, Susan C

2014-04-01

Mutations in fukutin-related protein (FKRP) underlie a group of muscular dystrophies associated with the hypoglycosylation of α-dystroglycan (α-DG), a proportion of which show central nervous system involvement. Our original FKRP knock-down mouse (FKRP(KD)) replicated many of the characteristics seen in patients at the severe end of the dystroglycanopathy spectrum but died perinatally precluding its full phenotyping and use in testing potential therapies. We have now overcome this by crossing FKRP(KD) mice with those expressing Cre recombinase under the Sox1 promoter. Owing to our original targeting strategy, this has resulted in the restoration of Fkrp levels in the central nervous system but not the muscle, thereby generating a new model (FKRP(MD)) which develops a progressive muscular dystrophy resembling what is observed in limb girdle muscular dystrophy. Like-acetylglucosaminyltransferase (LARGE) is a bifunctional glycosyltransferase previously shown to hyperglycosylate α-DG. To investigate the therapeutic potential of LARGE up-regulation, we have now crossed the FKRP(MD) line with one overexpressing LARGE and show that, contrary to expectation, this results in a worsening of the muscle pathology implying that any future strategies based upon LARGE up-regulation require careful management.

Pantethine treatment is effective in recovering the disease phenotype induced by ketogenic diet in a pantothenate kinase-associated neurodegeneration mouse model

PubMed Central

Brunetti, Dario; Dusi, Sabrina; Giordano, Carla; Lamperti, Costanza; Morbin, Michela; Fugnanesi, Valeria; Marchet, Silvia; Fagiolari, Gigliola; Sibon, Ody; Moggio, Maurizio; d’Amati, Giulia

2014-01-01

Pantothenate kinase-associated neurodegeneration, caused by mutations in the PANK2 gene, is an autosomal recessive disorder characterized by dystonia, dysarthria, rigidity, pigmentary retinal degeneration and brain iron accumulation. PANK2 encodes the mitochondrial enzyme pantothenate kinase type 2, responsible for the phosphorylation of pantothenate or vitamin B5 in the biosynthesis of co-enzyme A. A Pank2 knockout (Pank2−/−) mouse model did not recapitulate the human disease but showed azoospermia and mitochondrial dysfunctions. We challenged this mouse model with a low glucose and high lipid content diet (ketogenic diet) to stimulate lipid use by mitochondrial beta-oxidation. In the presence of a shortage of co-enzyme A, this diet could evoke a general impairment of bioenergetic metabolism. Only Pank2−/− mice fed with a ketogenic diet developed a pantothenate kinase-associated neurodegeneration-like syndrome characterized by severe motor dysfunction, neurodegeneration and severely altered mitochondria in the central and peripheral nervous systems. These mice also showed structural alteration of muscle morphology, which was comparable with that observed in a patient with pantothenate kinase-associated neurodegeneration. We here demonstrate that pantethine administration can prevent the onset of the neuromuscular phenotype in mice suggesting the possibility of experimental treatment in patients with pantothenate kinase-associated neurodegeneration. PMID:24316510

New treatment option for second-stage African sleeping sickness: in vitro and in vivo efficacy of aza analogs of DB289.

PubMed

Wenzler, Tanja; Boykin, David W; Ismail, Mohamed A; Hall, James Edwin; Tidwell, Richard R; Brun, Reto

2009-10-01

African sleeping sickness is a fatal parasitic disease, and all drugs currently in use for treatment have strong liabilities. It is essential to find new, effective, and less toxic drugs, ideally with oral application, to control the disease. In this study, the aromatic diamidine DB75 (furamidine) and two aza analogs, DB820 and DB829 (CPD-0801), as well as their methoxyamidine prodrugs and amidoxime metabolites, were evaluated against African trypanosomes. The active parent diamidines showed similar in vitro profiles against different Trypanosoma brucei strains, melarsoprol- and pentamidine-resistant lines, and a P2 transporter knockout strain (AT1KO), with DB75 as the most trypanocidal molecule. In the T. b. rhodesiense strain STIB900 acute mouse model, the aza analogs DB820 and DB829 demonstrated activities superior to that of DB75. The aza prodrugs DB844 and DB868, as well as two metabolites of DB844, were orally more potent in the T. b. brucei strain GVR35 mouse central nervous system (CNS) model than DB289 (pafuramidine maleate). Unexpectedly, the parent diamidine DB829 showed high activity in the mouse CNS model by the intraperitoneal route. In conclusion, DB868 with oral and DB829 with parenteral application are potential candidates for further development of a second-stage African sleeping sickness drug.

Foxp2 Regulates Gene Networks Implicated in Neurite Outgrowth in the Developing Brain

PubMed Central

Vernes, Sonja C.; Oliver, Peter L.; Spiteri, Elizabeth; Lockstone, Helen E.; Puliyadi, Rathi; Taylor, Jennifer M.; Ho, Joses; Mombereau, Cedric; Brewer, Ariel; Lowy, Ernesto; Nicod, Jérôme; Groszer, Matthias; Baban, Dilair; Sahgal, Natasha; Cazier, Jean-Baptiste; Ragoussis, Jiannis; Davies, Kay E.; Geschwind, Daniel H.; Fisher, Simon E.

2011-01-01

Forkhead-box protein P2 is a transcription factor that has been associated with intriguing aspects of cognitive function in humans, non-human mammals, and song-learning birds. Heterozygous mutations of the human FOXP2 gene cause a monogenic speech and language disorder. Reduced functional dosage of the mouse version (Foxp2) causes deficient cortico-striatal synaptic plasticity and impairs motor-skill learning. Moreover, the songbird orthologue appears critically important for vocal learning. Across diverse vertebrate species, this well-conserved transcription factor is highly expressed in the developing and adult central nervous system. Very little is known about the mechanisms regulated by Foxp2 during brain development. We used an integrated functional genomics strategy to robustly define Foxp2-dependent pathways, both direct and indirect targets, in the embryonic brain. Specifically, we performed genome-wide in vivo ChIP–chip screens for Foxp2-binding and thereby identified a set of 264 high-confidence neural targets under strict, empirically derived significance thresholds. The findings, coupled to expression profiling and in situ hybridization of brain tissue from wild-type and mutant mouse embryos, strongly highlighted gene networks linked to neurite development. We followed up our genomics data with functional experiments, showing that Foxp2 impacts on neurite outgrowth in primary neurons and in neuronal cell models. Our data indicate that Foxp2 modulates neuronal network formation, by directly and indirectly regulating mRNAs involved in the development and plasticity of neuronal connections. PMID:21765815

Foxp2 regulates gene networks implicated in neurite outgrowth in the developing brain.

PubMed

Vernes, Sonja C; Oliver, Peter L; Spiteri, Elizabeth; Lockstone, Helen E; Puliyadi, Rathi; Taylor, Jennifer M; Ho, Joses; Mombereau, Cedric; Brewer, Ariel; Lowy, Ernesto; Nicod, Jérôme; Groszer, Matthias; Baban, Dilair; Sahgal, Natasha; Cazier, Jean-Baptiste; Ragoussis, Jiannis; Davies, Kay E; Geschwind, Daniel H; Fisher, Simon E

2011-07-01

Forkhead-box protein P2 is a transcription factor that has been associated with intriguing aspects of cognitive function in humans, non-human mammals, and song-learning birds. Heterozygous mutations of the human FOXP2 gene cause a monogenic speech and language disorder. Reduced functional dosage of the mouse version (Foxp2) causes deficient cortico-striatal synaptic plasticity and impairs motor-skill learning. Moreover, the songbird orthologue appears critically important for vocal learning. Across diverse vertebrate species, this well-conserved transcription factor is highly expressed in the developing and adult central nervous system. Very little is known about the mechanisms regulated by Foxp2 during brain development. We used an integrated functional genomics strategy to robustly define Foxp2-dependent pathways, both direct and indirect targets, in the embryonic brain. Specifically, we performed genome-wide in vivo ChIP-chip screens for Foxp2-binding and thereby identified a set of 264 high-confidence neural targets under strict, empirically derived significance thresholds. The findings, coupled to expression profiling and in situ hybridization of brain tissue from wild-type and mutant mouse embryos, strongly highlighted gene networks linked to neurite development. We followed up our genomics data with functional experiments, showing that Foxp2 impacts on neurite outgrowth in primary neurons and in neuronal cell models. Our data indicate that Foxp2 modulates neuronal network formation, by directly and indirectly regulating mRNAs involved in the development and plasticity of neuronal connections.

Targeted Lipidomic Analysis of Oxysterols in the Embryonic Central Nervous System

PubMed Central

Wang, Yuqin; Sousa, Kyle M.; Bodin, Karl; Theofilopoulos, Spyridon; Sacchetti, Paola; Hornshaw, Martin; Woffendin, Gary; Karu, Kersti; Sjövall, Jan; Arenas, Ernest; Griffiths, William J.

2009-01-01

Summary In this study two regions of embryonic (E11) mouse central nervous system (CNS) have been profiled for their unesterified sterol content. Using high-performance liquid chromatography (HPLC) – mass spectrometry (MS) and tandem mass spectrometry (MSn) low levels of oxysterols (estimated 2 – 165 ng/g wet weight) were identified in cortex (Ctx) and spinal cord (Sc). The identified oxysterols include 7α-, 7β-, 22R-, 24S-, 25- and 27-hydroxycholesterol; 24,25- and 24,27-dihydroxycholesterol; and 24S,25-epoxycholesterol. Of these, 24S-hydroxycholesterol is biosynthesised exclusively in brain. In comparison to adult mouse where the 24S-hydroxycholesterol level is about 40 μg/g in brain the level of 24S-hydroxycholesterol reported here (estimated 26 ng/g in Ctx and 13 ng/g in Sc) is extremely low. Interestingly, the level of 24S,25-epoxycholesterol in both CNS regions (estimated 165 ng/g in Ctx and 91 ng/g in Sc) is somewhat higher than the levels of the hydroxycholesterols. This oxysterol is formed in parallel to cholesterol via a shunt of the mevalonate pathway and its comparatively high abundance may be a reflection of a high rate of cholesterol synthesis at this stage of development. Levels of cholesterol (estimated 1.25 mg/g in Ctx and 1.15 mg/g in Sc) and its precursors were determined by gas chromatography – mass spectrometry (GC-MS). In both CNS regions cholesterol levels were found to be lower than those reported in the adult, but in relation to cholesterol the levels of cholesterol precursors were higher than found in adult indicating a high rate of cholesterol synthesis. In summary, our data provide evidence for the presence of endogenous oxysterols in two brain regions of the developing CNS. Moreover, while most of the enzymes involved in hydroxysterol synthesis are minimally active at E11, our results suggest that the mevalonate pathway is significantly active, opening up the possibility for a function of 24S,25-epoxycholesterol during brain development. PMID:19381367

Inhibitor(s) of the classical complement pathway in mouse serum limit the utility of mice as experimental models of neuromyelitis optica.

PubMed

Ratelade, Julien; Verkman, A S

2014-11-01

Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system in which anti-aquaporin-4 (AQP4) autoantibodies (AQP4-IgG) cause damage to astrocytes by complement-dependent cytotoxicity (CDC). Various approaches have been attempted to produce NMO lesions in rodents, some involving genetically modified mice with altered immune cell function. Here, we found that mouse serum strongly inhibits complement from multiple species, preventing AQP4-IgG-dependent CDC. Effects of mouse serum on complement activation were tested in CDC assays in which AQP4-expressing cells were incubated with AQP4-IgG and complement from different species. Biochemical assays and mass spectrometry were used to characterize complement inhibitor(s) in mouse serum. Sera from different strains of mice produced almost no AQP4-IgG-dependent CDC compared with human, rat and guinea pig sera. Remarkably, addition of mouse serum prevented AQP4-IgG-dependent CDC caused by human, rat or guinea pig serum, with 50% inhibition at <5% mouse serum. Hemolysis assays indicated that the inhibitor(s) in mouse serum target the classical and not the alternative complement pathway. We found that the complement inhibitor(s) in mouse serum were contained in a serum fraction purified with protein-A resin; however, the inhibitor was not IgG as determined using serum from IgG-deficient mice. Mass spectrometry on the protein A-purified fraction produced several inhibitor candidates. The low intrinsic complement activity of mouse serum and the presence of complement inhibitor(s) limit the utility of mouse models to study disorders, such as NMO, involving the classical complement pathway. Copyright © 2014 Elsevier Ltd. All rights reserved.

Diverse pathogenicity of equine herpesvirus 1 (EHV-1) isolates in CBA mouse model.

PubMed

Yu, Mi Htay Htay; Kasem, Samy Gomaa Ahmed; Tsujimura, Koji; Matsumura, Tomio; Yanai, Tokuma; Yamaguchi, Tsuyoshi; Ohya, Kenji; Fukushi, Hideto

2010-03-01

The pathogenicity of equine herpesvirus 1 (EHV-1) isolates of Japan were evaluated by using the CBA mouse model. CBA mice were inoculated with eight Japanese EHV-1 strains (89c1, 90c16, 90c18, 97c11, 98c12, 00c19, 01c1 and HH-1) and one British strain (Ab4p). 89c1 caused slight body weight loss and nervous signs in mice at 8 days post infection (dpi). Severe weight loss and nervous signs were observed in mice inoculated with Ab4p at 6 dpi. The other strains did not cause apparent clinical signs. Infectious viruses were recovered from the lungs of all groups at 2 dpi. Histopathological analysis revealed interstitial pneumonia in the lungs of all mice inoculated with EHV-1. Encephalitis or meningoencephalitis was observed in the brains of mice inoculated with 89c1, 90c18, 97c11, 98c12, 01c1 and Ab4p. Japanese EHV-1 strains showed low pathogenicity in CBA mice, whereas the sequential affects of infection are similar to those of the highly pathogenic strain Ab4p. These results suggest that field isolates of EHV-1 have varying degrees of pathogenicity in CBA mice.

Leptin regulation of bone resorption by the sympathetic nervous system and CART.

PubMed

Elefteriou, Florent; Ahn, Jong Deok; Takeda, Shu; Starbuck, Michael; Yang, Xiangli; Liu, Xiuyun; Kondo, Hisataka; Richards, William G; Bannon, Tony W; Noda, Masaki; Clement, Karine; Vaisse, Christian; Karsenty, Gerard

2005-03-24

Bone remodelling, the mechanism by which vertebrates regulate bone mass, comprises two phases, namely resorption by osteoclasts and formation by osteoblasts; osteoblasts are multifunctional cells also controlling osteoclast differentiation. Sympathetic signalling via beta2-adrenergic receptors (Adrb2) present on osteoblasts controls bone formation downstream of leptin. Here we show, by analysing Adrb2-deficient mice, that the sympathetic nervous system favours bone resorption by increasing expression in osteoblast progenitor cells of the osteoclast differentiation factor Rankl. This sympathetic function requires phosphorylation (by protein kinase A) of ATF4, a cell-specific CREB-related transcription factor essential for osteoblast differentiation and function. That bone resorption cannot increase in gonadectomized Adrb2-deficient mice highlights the biological importance of this regulation, but also contrasts sharply with the increase in bone resorption characterizing another hypogonadic mouse with low sympathetic tone, the ob/ob mouse. This discrepancy is explained, in part, by the fact that CART ('cocaine amphetamine regulated transcript'), a neuropeptide whose expression is controlled by leptin and nearly abolished in ob/ob mice, inhibits bone resorption by modulating Rankl expression. Our study establishes that leptin-regulated neural pathways control both aspects of bone remodelling, and demonstrates that integrity of sympathetic signalling is necessary for the increase in bone resorption caused by gonadal failure.

Serial transmission in rodents of neurodegeneration from transgenic mice expressing mutant prion protein.

PubMed Central

Hsiao, K K; Groth, D; Scott, M; Yang, S L; Serban, H; Rapp, D; Foster, D; Torchia, M; Dearmond, S J; Prusiner, S B

1994-01-01

Two lines of transgenic (Tg) mice expressing high (H) levels of the mutant P101L prion protein (PrP) developed a neurologic illness and central nervous system pathology indistinguishable from experimental murine scrapie; these mice were designated Tg(MoPrP-P101L)H. Brain homogenates from Tg(MoPrP-P101L)H mice were inoculated intracerebrally into CD-1 Swiss mice, Syrian hamsters, and Tg196 mice, Tg mice expressing the MoPrP-P101L transgene at low levels. None of the CD-1 mice developed central nervous system dysfunction, whereas approximately 10% of hamsters and approximately 40% of the Tg196 mice manifested neurologic signs between 117 and 639 days after inoculation. Serial transmission of neurodegeneration in Tg196 mice and Syrian hamsters was initiated with brain extracts, producing incubation times of approximately 400 and approximately 75 days, respectively. Although the Tg(MoPrP-P101L)H mice appear to accumulate only low levels of infections prions in their brains, the serial transmission of disease to inoculated recipients argues that prion formation occurs de novo in the brains of these uninoculated animals. These Tg mouse studies, taken together with similar findings in humans dying of inherited prion diseases, provide additional evidence that prions lack a foreign nucleic acid. Images PMID:7916462

Selective Constraints on Coding Sequences of Nervous System Genes Are a Major Determinant of Duplicate Gene Retention in Vertebrates

PubMed Central

Roux, Julien; Liu, Jialin; Robinson-Rechavi, Marc

2017-01-01

Abstract The evolutionary history of vertebrates is marked by three ancient whole-genome duplications: two successive rounds in the ancestor of vertebrates, and a third one specific to teleost fishes. Biased loss of most duplicates enriched the genome for specific genes, such as slow evolving genes, but this selective retention process is not well understood. To understand what drives the long-term preservation of duplicate genes, we characterized duplicated genes in terms of their expression patterns. We used a new method of expression enrichment analysis, TopAnat, applied to in situ hybridization data from thousands of genes from zebrafish and mouse. We showed that the presence of expression in the nervous system is a good predictor of a higher rate of retention of duplicate genes after whole-genome duplication. Further analyses suggest that purifying selection against the toxic effects of misfolded or misinteracting proteins, which is particularly strong in nonrenewing neural tissues, likely constrains the evolution of coding sequences of nervous system genes, leading indirectly to the preservation of duplicate genes after whole-genome duplication. Whole-genome duplications thus greatly contributed to the expansion of the toolkit of genes available for the evolution of profound novelties of the nervous system at the base of the vertebrate radiation. PMID:28981708

Development of cardiac parasympathetic neurons, glial cells, and regional cholinergic innervation of the mouse heart.

PubMed

Fregoso, S P; Hoover, D B

2012-09-27

Very little is known about the development of cardiac parasympathetic ganglia and cholinergic innervation of the mouse heart. Accordingly, we evaluated the growth of cholinergic neurons and nerve fibers in mouse hearts from embryonic day 18.5 (E18.5) through postnatal day 21(P21). Cholinergic perikarya and varicose nerve fibers were identified in paraffin sections immunostained for the vesicular acetylcholine transporter (VAChT). Satellite cells and Schwann cells in adjacent sections were identified by immunostaining for S100β calcium binding protein (S100) and brain-fatty acid binding protein (B-FABP). We found that cardiac ganglia had formed in close association to the atria and cholinergic innervation of the atrioventricular junction had already begun by E18.5. However, most cholinergic innervation of the heart, including the sinoatrial node, developed postnatally (P0.5-P21) along with a doubling of the cross-sectional area of cholinergic perikarya. Satellite cells were present throughout neonatal cardiac ganglia and expressed primarily B-FABP. As they became more mature at P21, satellite cells stained strongly for both B-FABP and S100. Satellite cells appeared to surround most cardiac parasympathetic neurons, even in neonatal hearts. Mature Schwann cells, identified by morphology and strong staining for S100, were already present at E18.5 in atrial regions that receive cholinergic innervation at later developmental times. The abundance and distribution of S100-positive Schwann cells increased postnatally along with nerve density. While S100 staining of cardiac Schwann cells was maintained in P21 and older mice, Schwann cells did not show B-FABP staining at these times. Parallel development of satellite cells and cholinergic perikarya in the cardiac ganglia and the increase in abundance of Schwann cells and varicose cholinergic nerve fibers in the atria suggest that neuronal-glial interactions could be important for development of the parasympathetic nervous system in the heart. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Cerebellar microfolia and other abnormalities of neuronal growth, migration, and lamination in the Pit1dw-J homozygote mutant mouse

NASA Technical Reports Server (NTRS)

Sekiguchi, M.; Abe, H.; Moriya, M.; Tanaka, O.; Nowakowski, R. S.

1998-01-01

The Snell dwarf mouse (Pit1dw-J homozygote) has a mutation in the Pit1 gene that prevents the normal formation of the anterior pituitary. In neonates and adults there is almost complete absence of growth hormone (GH), prolactin (PRL), thyroxin (T4), and thyroid-stimulating hormone (TSH). Since these hormones have been suggested to play a role in normal development of the central nervous system (CNS), we have investigated the effects of the Pit1dw-J mutation on the cerebellum and hippocampal formation. In the cerebellum, there were abnormalities of both foliation and lamination. The major foliation anomalies were 1) changes in the relative size of specific folia and also the proportional sizes of the anterior vs posterior cerebellum; and 2) the presence of between one and three microfolia per half cerebellum. The microfolia were all in the medial portion of the hemisphere in the caudal part of the cerebellum. Each microfolium was just rostral to a normal fissure and interposed between the fissure and a normal gyrus. Lamination abnormalities included an increase in the number of single ectopic granule cells in the molecular layer in both cerebellar vermis (86%) and hemisphere (40%) in comparison with the wild-type mouse. In the hippocampus of the Pit1dw-J homozygote mouse, the number of pyramidal cells was decreased, although the width of the pyramidal cell layer throughout areas CA1-CA3 appeared to be normal, but less densely populated than in the wild-type mouse. Moreover, the number of granule cells that form the granule cell layer was decreased from the wild-type mouse and some ectopic granule cells (occurring both as single cells and as small clusters) were observed in the innermost portion of the molecular layer. The abnormalities observed in the Pit1dw-J homozygote mouse seem to be caused by both direct and indirect effects of the deficiency of TSH (or T4), PRL, or GH rather than by a direct effect of the deletion of Pit1.

Exacerbation of experimental autoimmune encephalomyelitis by passive transfer of IgG antibodies from a multiple sclerosis patient responsive to immunoadsorption.

PubMed

Pedotti, Rosetta; Musio, Silvia; Scabeni, Stefano; Farina, Cinthia; Poliani, Pietro Luigi; Colombo, Emanuela; Costanza, Massimo; Berzi, Angela; Castellucci, Fabrizio; Ciusani, Emilio; Confalonieri, Paolo; Hemmer, Bernhard; Mantegazza, Renato; Antozzi, Carlo

2013-09-15

The pathogenic role of antibodies in multiple sclerosis (MS) is still controversial. We transferred to mice with experimental autoimmune encephalomyelitis (EAE), animal model of MS, IgG antibodies purified from a MS patient presenting a dramatic clinical improvement during relapse after selective IgG removal with immunoadsorption. Passive transfer of patient's IgG exacerbated motor paralysis and increased mouse central nervous system (CNS) inflammation and demyelination. Binding of patient's IgG was demonstrated in mouse CNS, with a diffuse staining of white matter oligodendrocytes. These data support a growing body of evidence that antibodies can play an important role in the pathobiology of MS. Copyright © 2013 Elsevier B.V. All rights reserved.

Generation of a neuro-specific microarray reveals novel differentially expressed noncoding RNAs in mouse models for neurodegenerative diseases.

PubMed

Gstir, Ronald; Schafferer, Simon; Scheideler, Marcel; Misslinger, Matthias; Griehl, Matthias; Daschil, Nina; Humpel, Christian; Obermair, Gerald J; Schmuckermair, Claudia; Striessnig, Joerg; Flucher, Bernhard E; Hüttenhofer, Alexander

2014-12-01

We have generated a novel, neuro-specific ncRNA microarray, covering 1472 ncRNA species, to investigate their expression in different mouse models for central nervous system diseases. Thereby, we analyzed ncRNA expression in two mouse models with impaired calcium channel activity, implicated in Epilepsy or Parkinson's disease, respectively, as well as in a mouse model mimicking pathophysiological aspects of Alzheimer's disease. We identified well over a hundred differentially expressed ncRNAs, either from known classes of ncRNAs, such as miRNAs or snoRNAs or which represented entirely novel ncRNA species. Several differentially expressed ncRNAs in the calcium channel mouse models were assigned as miRNAs and target genes involved in calcium signaling, thus suggesting feedback regulation of miRNAs by calcium signaling. In the Alzheimer mouse model, we identified two snoRNAs, whose expression was deregulated prior to amyloid plaque formation. Interestingly, the presence of snoRNAs could be detected in cerebral spine fluid samples in humans, thus potentially serving as early diagnostic markers for Alzheimer's disease. In addition to known ncRNAs species, we also identified 63 differentially expressed, entirely novel ncRNA candidates, located in intronic or intergenic regions of the mouse genome, genomic locations, which previously have been shown to harbor the majority of functional ncRNAs. © 2014 Gstir et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Mouse models of neurodegenerative diseases: criteria and general methodology.

PubMed

Janus, Christopher; Welzl, Hans

2010-01-01

The major symptom of Alzheimer's disease is rapidly progressing dementia, coinciding with the formation of amyloid and tau deposits in the central nervous system, and neuronal death. At present familial cases of dementias provide the most promising foundation for modelling neurodegeneration. We describe the mnemonic and other major behavioral symptoms of tauopathies, briefly outline the genetics underlying familiar cases and discuss the arising implications for modelling the disease in mostly transgenic mouse lines. We then depict to what degree the most recent mouse models replicate pathological and cognitive characteristics observed in patients.There is no universally valid behavioral test battery to evaluate mouse models. The selection of individual tests depends on the behavioral and/or memory system in focus, the type of a model and how well it replicates the pathology of a disease and the amount of control over the genetic background of the mouse model. However it is possible to provide guidelines and criteria for modelling the neurodegeneration, setting up the experiments and choosing relevant tests. One should not adopt a "one (trans)gene, one disease" interpretation, but should try to understand how the mouse genome copes with the protein expression of the transgene in question. Further, it is not possible to recommend some mouse models over others since each model is valuable within its own constraints, and the way experiments are performed often reflects the idiosyncratic reality of specific laboratories. Our purpose is to improve bridging molecular and behavioural approaches in translational research.

Distribution of vesicular glutamate transporter 1 (VGLUT1) in the mouse esophagus.

PubMed

Kraus, T; Neuhuber, W L; Raab, M

2007-08-01

In rat and mouse esophagus, vesicular glutamate transporter 2 (VGLUT2) has been demonstrated to identify vagal intraganglionic laminar endings (IGLEs); this has recently also been shown for VGLUT1 in rat esophagus. In this study, we have investigated the distribution of VGLUT1 in the mouse esophagus and compared these results with the recently published data from the rat esophagus. Unexpectedly, we have discovered that VGLUT1 mostly fails to identify IGLEs in the mouse esophagus. This is surprising, since the distribution of VGLUT2 shows comparable results in both species. Confocal imaging has revealed substantial colocalization of VGLUT1 immunoreactivity (-ir) with cholinergic and nitrergic/peptidergic markers within the myenteric neuropil and in both cholinergic and nitrergic myenteric neuronal cell bodies. VGLUT1 and cholinergic markers have also been colocalized in fibers of the muscularis mucosae, whereas VGLUT1 and nitrergic markers have never been colocalized in fibers of the muscularis mucosae, although this does occur in fibers of the muscularis running to motor endplates. Thus, VGLUT1 is contained in the nitrergic innervation of mouse esophageal motor endplates, another difference from the rat esophagus. VGLUT1-ir is therefore present in extrinsic and intrinsic innervation of the mouse esophagus, but the significant differences from the rat indicate species variations concerning the distribution of VGLUTs in the peripheral nervous system.

Central nervous system gene expression changes in a transgenic mouse model for bovine spongiform encephalopathy

PubMed Central

2011-01-01

Gene expression analysis has proven to be a very useful tool to gain knowledge of the factors involved in the pathogenesis of diseases, particularly in the initial or preclinical stages. With the aim of finding new data on the events occurring in the Central Nervous System in animals affected with Bovine Spongiform Encephalopathy, a comprehensive genome wide gene expression study was conducted at different time points of the disease on mice genetically modified to model the bovine species brain in terms of cellular prion protein. An accurate analysis of the information generated by microarray technique was the key point to assess the biological relevance of the data obtained in terms of Transmissible Spongiform Encephalopathy pathogenesis. Validation of the microarray technique was achieved by RT-PCR confirming the RNA change and immunohistochemistry techniques that verified that expression changes were translated into variable levels of protein for selected genes. Our study reveals changes in the expression of genes, some of them not previously associated with prion diseases, at early stages of the disease previous to the detection of the pathological prion protein, that might have a role in neuronal degeneration and several transcriptional changes showing an important imbalance in the Central Nervous System homeostasis in advanced stages of the disease. Genes whose expression is altered at early stages of the disease should be considered as possible therapeutic targets and potential disease markers in preclinical diagnostic tool development. Genes non-previously related to prion diseases should be taken into consideration for further investigations. PMID:22035425

Motor neuron cell-nonautonomous rescue of spinal muscular atrophy phenotypes in mild and severe transgenic mouse models

PubMed Central

Liu, Ying Hsiu; Sahashi, Kentaro; Rigo, Frank; Bennett, C. Frank

2015-01-01

Survival of motor neuron (SMN) deficiency causes spinal muscular atrophy (SMA), but the pathogenesis mechanisms remain elusive. Restoring SMN in motor neurons only partially rescues SMA in mouse models, although it is thought to be therapeutically essential. Here, we address the relative importance of SMN restoration in the central nervous system (CNS) versus peripheral tissues in mouse models using a therapeutic splice-switching antisense oligonucleotide to restore SMN and a complementary decoy oligonucleotide to neutralize its effects in the CNS. Increasing SMN exclusively in peripheral tissues completely rescued necrosis in mild SMA mice and robustly extended survival in severe SMA mice, with significant improvements in vulnerable tissues and motor function. Our data demonstrate a critical role of peripheral pathology in the mortality of SMA mice and indicate that peripheral SMN restoration compensates for its deficiency in the CNS and preserves motor neurons. Thus, SMA is not a cell-autonomous defect of motor neurons in SMA mice. PMID:25583329

Omics analysis of mouse brain models of human diseases.

PubMed

Paban, Véronique; Loriod, Béatrice; Villard, Claude; Buee, Luc; Blum, David; Pietropaolo, Susanna; Cho, Yoon H; Gory-Faure, Sylvie; Mansour, Elodie; Gharbi, Ali; Alescio-Lautier, Béatrice

2017-02-05

The identification of common gene/protein profiles related to brain alterations, if they exist, may indicate the convergence of the pathogenic mechanisms driving brain disorders. Six genetically engineered mouse lines modelling neurodegenerative diseases and neuropsychiatric disorders were considered. Omics approaches, including transcriptomic and proteomic methods, were used. The gene/protein lists were used for inter-disease comparisons and further functional and network investigations. When the inter-disease comparison was performed using the gene symbol identifiers, the number of genes/proteins involved in multiple diseases decreased rapidly. Thus, no genes/proteins were shared by all 6 mouse models. Only one gene/protein (Gfap) was shared among 4 disorders, providing strong evidence that a common molecular signature does not exist among brain diseases. The inter-disease comparison of functional processes showed the involvement of a few major biological processes indicating that brain diseases of diverse aetiologies might utilize common biological pathways in the nervous system, without necessarily involving similar molecules. Copyright © 2016 Elsevier B.V. All rights reserved.

Topical treatment of herpes simplex virus infection with enzymatically created siRNA swarm.

PubMed

Paavilainen, Henrik; Lehtinen, Jenni; Romanovskaya, Alesia; Nygårdas, Michaela; Bamford, Dennis H; Poranen, Minna M; Hukkanen, Veijo

2017-01-01

Herpes simplex virus (HSV) is a common human pathogen. Despite current antivirals, it causes a significant medical burden. Drug resistant strains exist and they are especially prevalent in immunocompromised patients and in HSV eye infections. New treatment modalities are needed. BALB/c mice were corneally infected with HSV and subsequently treated with a swarm of enzymatically created, Dicer-substrate small interfering RNA (siRNA) molecules that targeted the HSV gene UL29. Two infection models were used, one in which the infection was predominantly peripheral and another in which it spread to the central nervous system. Mouse survival, as well as viral spread, load, latency and peripheral shedding, was studied. The anti-HSV-UL29 siRNA swarm alleviated HSV infection symptoms, inhibited viral shedding and replication and had a favourable effect on mouse survival. Treatment with anti-HSV-UL29 siRNA swarm reduced symptoms and viral spread in HSV infection of mice and also inhibited local viral replication in mouse corneas.

All-fiber femtosecond laser providing 9 nJ, 50 MHz pulses at 1650 nm for three-photon microscopy

NASA Astrophysics Data System (ADS)

Cadroas, P.; Abdeladim, L.; Kotov, L.; Likhachev, M.; Lipatov, D.; Gaponov, D.; Hideur, A.; Tang, M.; Livet, J.; Supatto, W.; Beaurepaire, E.; Février, S.

2017-06-01

The spectral window lying between 1.6 and 1.7 μm is interesting for in-depth multiphoton microscopy of intact tissues due to reduced scattering and absorption in this wavelength range. However, wide adoption of this excitation range will rely on the availability of robust and cost-effective high peak power pulsed lasers operating at these wavelengths. In this communication, we report on a monolithically integrated high repetition rate (50 MHz) all-fiber femtosecond laser based on a soliton self-frequency shift providing 9 nJ, 75 fs pulses at 1650 nm. We illustrate its potential for biological microscopy by recording three-photon-excited fluorescence and third-harmonic generation images of mouse nervous tissue and developing Drosophila embryos labeled with a red fluorescent protein.

Aversive and non-aversive memory impairment in the mucopolysaccharidosis II mouse model.

PubMed

Azambuja, Amanda Stapenhorst; Correa, Lilian; Gabiatti, Bernardo Pappi; Martins, Giselle Renata; de Oliveira Franco, Álvaro; Ribeiro, Maria Flávia Marques; Baldo, Guilherme

2018-02-01

Hunter syndrome (MPS II, OMIM 309900) is a lysosomal storage disorder due to deficient iduronate sulphatase activity. Patients present multiple cognitive alterations, and the aim of this work was to verify if MPS II mice also present some progressive cognitive alterations. For that, MPS II mice from 2 to 6 months of age were submitted to repeated open field and inhibitory avoidance tests to evaluate memory parameters. MPS II mice presented impaired memory at 6 months evaluated by open field test. They also performed poorly in the inhibitory avoidance test from 4 months. We conclude that MPS II mice develop cognitive alterations as the disease progresses. These tests can be used in the future to study the efficacy of therapeutic approaches in the central nervous system.

Neuronal expression of fibroblast growth factor receptors in zebrafish.

PubMed

Rohs, Patricia; Ebert, Alicia M; Zuba, Ania; McFarlane, Sarah

2013-12-01

Fibroblast growth factor (FGF) signaling is important for a host of developmental processes such as proliferation, differentiation, tissue patterning, and morphogenesis. In vertebrates, FGFs signal through a family of four fibroblast growth factor receptors (FGFR 1-4), one of which is duplicated in zebrafish (FGFR1). Here we report the mRNA expression of the five known zebrafish fibroblast growth factor receptors at five developmental time points (24, 36, 48, 60, and 72h postfertilization), focusing on expression within the central nervous system. We show that the receptors have distinct and dynamic expression in the developing zebrafish brain, eye, inner ear, lateral line, and pharynx. In many cases, the expression patterns are similar to those of homologous FGFRs in mouse, chicken, amphibians, and other teleosts. Copyright © 2013 Elsevier B.V. All rights reserved.

Ketone esters increase brown fat in mice and overcome insulin resistance in other tissues in the rat.

PubMed

Veech, Richard L

2013-10-01

Brown adipose tissue (BAT) is classically activated by sympathetic nervous stimulation resulting from exposure to cold. Feeding a high-fat diet also induces development of brown fat, but is decreased by caloric restriction. Blood ketone bodies, which function as alternative energy substrates to glucose, are increased during caloric restriction. Here we discuss the unexpected observation that feeding an ester of ketone bodies to the mouse, which increases blood ketone body concentrations, results in an activation of brown fat. The mechanism of this activation of brown fat is similar to that occurring from cold exposure in that cyclic adenosine monophosphate (AMP) levels are increased as are levels of the transcription factor cyclic AMP-responsive element-binding protein, which is also increased by ketone ester feeding. Other effects of feeding ketone esters, in addition to their ability to induce brown fat, are discussed such as their ability to overcome certain aspects of insulin resistance and to ameliorate the accumulation of amyloid and phosphorylated tau protein in brain, and improve cognitive function, in a triple transgenic mouse model of Alzheimer's disease. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Central nervous system activity of the ethanol leaf extract of Sida acuta in rats.

PubMed

Ibironke, G F; Umukoro, A S; Ajonijebu, D C

2014-03-01

The study investigated the pharmacological effects of ethanol extract of Sida acuta leaves on central nervous system activities in mice. Adult male mice (18 - 25g) were used for the study. The extract was administered orally in male mice and evaluated in the following tests: forced swimming, tail suspension, formalin-induced paw licking, acetic acid--induced mouse writhing and apomorphine-induced stereotypy. The results revealed a reduction in the frequency of abdominal constrictions induced by acetic acid, decreased licking times in both phases of the formalin test, reduction in immobility times in forced swimming and tail suspension tests. However, the extract produced no effect on apomorphine-induced stereotyped behaviour. These results suggest that the ethanol extract of Sida acuta contains psychoactive substances with analgesic and antidepressant-like properties which may be beneficial in the management of pain.

Nicotinic acetylcholine receptor alpha5 subunits modulate oxotremorine-induced salivation and tremor.

PubMed

Wang, Ningshan; Orr-Urtreger, Avi; Chapman, Joab; Rabinowitz, Ruth; Korczyn, Amos D

2004-07-15

Neuronal nicotinic acetylcholine receptors (nAChRs) are composed of 12 subunits (alpha2-alpha10 and beta2-beta4). alpha5 Subunits, expressed throughout the central nervous system (CNS) and the autonomic nervous system (ANS), possess unique pharmacological properties. The effects of oxotremorine (OXO) on autonomic functions and tremor were examined in mice lacking alpha5 nAChR subunits (alpha5-/-) and compared with those in wild-type (WT) control mice. The alpha5-/- mice showed significantly increased salivation and tremor responses to OXO. The hypothermia, bradycardia and defecation induced by OXO were of similar magnitudes in the two mouse strains. The enhanced OXO effects in alpha5-/- mice indicate inhibitory effects of alpha5 subunits in autonomic ganglia, and support the participation of these subunits in cholinergic transmission in autonomic ganglia.

Dimethyl Sulfoxide (DMSO) Produces Widespread Apoptosis in the Developing Central Nervous System

PubMed Central

Hanslick, Jennifer L.; Lau, Karen; Noguchi, Kevin K.; Olney, John W.; Zorumski, Charles F.; Mennerick, Steven; Farber, Nuri B.

2009-01-01

Dimethyl sulfoxide (DMSO) is a solvent that is routinely used as a cryopreservative in allogous bone marrow and organ transplantion. We exposed C57Bl/6 mice of varying postnatal ages (P0–P30) to DMSO in order to study whether DMSO could produce apoptotic degeneration in the developing CNS. DMSO produced widespread apoptosis in the developing mouse brain at all ages tested. Damage was greatest at P7. Significant elevations above the background rate of apoptosis occurred at the lowest dose tested, 0.3 ml/kg. In an in vitro rat hippocampal culture preparation, DMSO produced neuronal loss at concentrations of 0.5% and 1.0%. The ability of DMSO to damage neurons in dissociated cultures indicates that the toxicity likely results from a direct cellular effect. Because children, who undergo bone marrow transplantation, are routinely exposed to DMSO at doses higher than 0.3 ml/kg, there is concern that DMSO might be producing similar damage in human children. PMID:19100327

Mice Lacking the Giant Protocadherin mFAT1 Exhibit Renal Slit Junction Abnormalities and a Partially Penetrant Cyclopia and Anophthalmia Phenotype

PubMed Central

Ciani, Lorenza; Patel, Anjla; Allen, Nicholas D.; ffrench-Constant, Charles

2003-01-01

While roles in adhesion and morphogenesis have been documented for classical cadherins, the nonclassical cadherins are much less well understood. Here we have examined the functions of the giant protocadherin FAT by generating a transgenic mouse lacking mFAT1. These mice exhibit perinatal lethality, most probably caused by loss of the renal glomerular slit junctions and fusion of glomerular epithelial cell processes (podocytes). In addition, some mFAT1−/− mice show defects in forebrain development (holoprosencephaly) and failure of eye development (anophthalmia). In contrast to Drosophila, where FAT acts as a tumor suppressor gene, we found no evidence for abnormalities of proliferation in two tissues (skin and central nervous system [CNS]) containing stem and precursor cell populations and in which FAT is expressed strongly. Our results confirm a necessary role for FAT1 in the modified adhesion junctions of the renal glomerular epithelial cell and reveal hitherto unsuspected roles for FAT1 in CNS development. PMID:12724416

Adrenergic Signaling: A Targetable Checkpoint Limiting Development of the Antitumor Immune Response.

PubMed

Qiao, Guanxi; Chen, Minhui; Bucsek, Mark J; Repasky, Elizabeth A; Hylander, Bonnie L

2018-01-01

An immune response must be tightly controlled so that it will be commensurate with the level of response needed to protect the organism without damaging normal tissue. The roles of cytokines and chemokines in orchestrating these processes are well known, but although stress has long been thought to also affect immune responses, the underlying mechanisms were not as well understood. Recently, the role of nerves and, specifically, the sympathetic nervous system, in regulating immune responses is being revealed. Generally, an acute stress response is beneficial but chronic stress is detrimental because it suppresses the activities of effector immune cells while increasing the activities of immunosuppressive cells. In this review, we first discuss the underlying biology of adrenergic signaling in cells of both the innate and adaptive immune system. We then focus on the effects of chronic adrenergic stress in promoting tumor growth, giving examples of effects on tumor cells and immune cells, explaining the methods commonly used to induce stress in preclinical mouse models. We highlight how this relates to our observations that mandated housing conditions impose baseline chronic stress on mouse models, which is sufficient to cause chronic immunosuppression. This problem is not commonly recognized, but it has been shown to impact conclusions of several studies of mouse physiology and mouse models of disease. Moreover, the fact that preclinical mouse models are chronically immunosuppressed has critical ramifications for analysis of any experiments with an immune component. Our group has found that reducing adrenergic stress by housing mice at thermoneutrality or treating mice housed at cooler temperatures with β-blockers reverses immunosuppression and significantly improves responses to checkpoint inhibitor immunotherapy. These observations are clinically relevant because there are numerous retrospective epidemiological studies concluding that cancer patients who were taking β-blockers have better outcomes. Clinical trials testing whether β-blockers can be repurposed to improve the efficacy of traditional and immunotherapies in patients are on the horizon.

Adrenergic Signaling: A Targetable Checkpoint Limiting Development of the Antitumor Immune Response

PubMed Central

Qiao, Guanxi; Chen, Minhui; Bucsek, Mark J.; Repasky, Elizabeth A.; Hylander, Bonnie L.

2018-01-01

An immune response must be tightly controlled so that it will be commensurate with the level of response needed to protect the organism without damaging normal tissue. The roles of cytokines and chemokines in orchestrating these processes are well known, but although stress has long been thought to also affect immune responses, the underlying mechanisms were not as well understood. Recently, the role of nerves and, specifically, the sympathetic nervous system, in regulating immune responses is being revealed. Generally, an acute stress response is beneficial but chronic stress is detrimental because it suppresses the activities of effector immune cells while increasing the activities of immunosuppressive cells. In this review, we first discuss the underlying biology of adrenergic signaling in cells of both the innate and adaptive immune system. We then focus on the effects of chronic adrenergic stress in promoting tumor growth, giving examples of effects on tumor cells and immune cells, explaining the methods commonly used to induce stress in preclinical mouse models. We highlight how this relates to our observations that mandated housing conditions impose baseline chronic stress on mouse models, which is sufficient to cause chronic immunosuppression. This problem is not commonly recognized, but it has been shown to impact conclusions of several studies of mouse physiology and mouse models of disease. Moreover, the fact that preclinical mouse models are chronically immunosuppressed has critical ramifications for analysis of any experiments with an immune component. Our group has found that reducing adrenergic stress by housing mice at thermoneutrality or treating mice housed at cooler temperatures with β-blockers reverses immunosuppression and significantly improves responses to checkpoint inhibitor immunotherapy. These observations are clinically relevant because there are numerous retrospective epidemiological studies concluding that cancer patients who were taking β-blockers have better outcomes. Clinical trials testing whether β-blockers can be repurposed to improve the efficacy of traditional and immunotherapies in patients are on the horizon. PMID:29479349

Protein phosphatase 2ACα gene knock-out results in cortical atrophy through activating hippo cascade in neuronal progenitor cells.

PubMed

Liu, Bo; Sun, Li-Hua; Huang, Yan-Fei; Guo, Li-Jun; Luo, Li-Shu

2018-02-01

Protein phosphatase 2ACα (PP2ACα), a vital member of the protein phosphatase family, has been studied primarily as a regulator for the development, growth and protein synthesis of a lot of cell types. Dysfunction of PP2ACα protein results in neurodegenerative disease; however, this finding has not been directly confirmed in the mouse model with PP2ACα gene knock-out. Therefore, in this study presented here, we generated the PP2ACα gene knock-out mouse model by the Cre-loxP targeting gene system, with the purpose to directly observe the regulatory role of PP2ACα gene in the development of mouse's cerebral cortex. We observe that knocking-out PP2ACα gene in the central nervous system (CNS) results in cortical neuronal shrinkage, synaptic plasticity impairments, and learning/memory deficits. Further study reveals that PP2ACα gene knock-out initiates Hippo cascade in cortical neuroprogenitor cells (NPCs), which blocks YAP translocation into the nuclei of NPCs. Notably, p73, directly targeted by Hippo cascade, can bind to the promoter of glutaminase2 (GLS2) that plays a dominant role in the enzymatic regulation of glutamate/glutamine cycle. Finally, we find that PP2ACα gene knock-out inhibits the glutamine synthesis through up-regulating the activity of phosphorylated-p73 in cortical NPCs. Taken together, it concludes that PP2ACα critically supports cortical neuronal growth and cognitive function via regulating the signaling transduction of Hippo-p73 cascade. And PP2ACα indirectly modulates the glutamine synthesis of cortical NPCs through targeting p73 that plays a direct transcriptional regulatory role in the gene expression of GLS2. Copyright © 2017 Elsevier Ltd. All rights reserved.

Complete or partial reduction of the Met receptor tyrosine kinase in distinct circuits differentially impacts mouse behavior.

PubMed

Thompson, Barbara L; Levitt, Pat

2015-01-01

Our laboratory discovered that the gene encoding the receptor tyrosine kinase, MET, contributes to autism risk. Expression of MET is reduced in human postmortem temporal lobe in autism and Rett Syndrome. Subsequent studies revealed a role for MET in human and mouse functional and structural cortical connectivity. To further understand the contribution of Met to brain development and its impact on behavior, we generated two conditional mouse lines in which Met is deleted from select populations of central nervous system neurons. Mice were then tested to determine the consequences of disrupting Met expression. Mating of Emx1 (cre) and Met (fx/fx) mice eliminates receptor signaling from all cells arising from the dorsal pallium. Met (fx/fx) and Nestin (cre) crosses result in receptor signaling elimination from all neural cells. Behavioral tests were performed to assess cognitive, emotional, and social impairments that are observed in multiple neurodevelopmental disorders and that are in part subserved by circuits that express Met. Met (fx/fx) /Emx1 (cre) null mice displayed significant hypoactivity in the activity chamber and in the T-maze despite superior performance on the rotarod. Additionally, these animals showed a deficit in spontaneous alternation. Surprisingly, Met (fx/fx; fx/+) /Nestin (cre) null and heterozygous mice exhibited deficits in contextual fear conditioning, and Met (fx/+) /Nestin (cre) heterozygous mice spent less time in the closed arms of the elevated plus maze. These data suggest a complex contribution of Met in the development of circuits mediating social, emotional, and cognitive behavior. The impact of disrupting developmental Met expression is dependent upon circuit-specific deletion patterns and levels of receptor activity.

A mesoscale connectome of the mouse brain

PubMed Central

Oh, Seung Wook; Harris, Julie A.; Ng, Lydia; Winslow, Brent; Cain, Nicholas; Mihalas, Stefan; Wang, Quanxin; Lau, Chris; Kuan, Leonard; Henry, Alex M.; Mortrud, Marty T.; Ouellette, Benjamin; Nguyen, Thuc Nghi; Sorensen, Staci A.; Slaughterbeck, Clifford R.; Wakeman, Wayne; Li, Yang; Feng, David; Ho, Anh; Nicholas, Eric; Hirokawa, Karla E.; Bohn, Phillip; Joines, Kevin M.; Peng, Hanchuan; Hawrylycz, Michael J.; Phillips, John W.; Hohmann, John G.; Wohnoutka, Paul; Gerfen, Charles R.; Koch, Christof; Bernard, Amy; Dang, Chinh; Jones, Allan R.; Zeng, Hongkui

2016-01-01

Comprehensive knowledge of the brain’s wiring diagram is fundamental for understanding how the nervous system processes information at both local and global scales. However, with the singular exception of the C. elegans microscale connectome, there are no complete connectivity data sets in other species. Here we report a brain-wide, cellular-level, mesoscale connectome for the mouse. The Allen Mouse Brain Connectivity Atlas uses enhanced green fluorescent protein (EGFP)-expressing adeno-associated viral vectors to trace axonal projections from defined regions and cell types, and high-throughput serial two-photon tomography to image the EGFP-labelled axons throughout the brain. This systematic and standardized approach allows spatial registration of individual experiments into a common three dimensional (3D) reference space, resulting in a whole-brain connectivity matrix. A computational model yields insights into connectional strength distribution, symmetry and other network properties. Virtual tractography illustrates 3D topography among interconnected regions. Cortico-thalamic pathway analysis demonstrates segregation and integration of parallel pathways. The Allen Mouse Brain Connectivity Atlas is a freely available, foundational resource for structural and functional investigations into the neural circuits that support behavioural and cognitive processes in health and disease. PMID:24695228

Silencing neuronal mutant androgen receptor in a mouse model of spinal and bulbar muscular atrophy.

PubMed

Sahashi, Kentaro; Katsuno, Masahisa; Hung, Gene; Adachi, Hiroaki; Kondo, Naohide; Nakatsuji, Hideaki; Tohnai, Genki; Iida, Madoka; Bennett, C Frank; Sobue, Gen

2015-11-01

Spinal and bulbar muscular atrophy (SBMA), an adult-onset neurodegenerative disease that affects males, results from a CAG triplet repeat/polyglutamine expansions in the androgen receptor (AR) gene. Patients develop progressive muscular weakness and atrophy, and no effective therapy is currently available. The tissue-specific pathogenesis, especially relative pathological contributions between degenerative motor neurons and muscles, remains inconclusive. Though peripheral pathology in skeletal muscle caused by toxic AR protein has been recently reported to play a pivotal role in the pathogenesis of SBMA using mouse models, the role of motor neuron degeneration in SBMA has not been rigorously investigated. Here, we exploited synthetic antisense oligonucleotides to inhibit the RNA levels of mutant AR in the central nervous system (CNS) and explore its therapeutic effects in our SBMA mouse model that harbors a mutant AR gene with 97 CAG expansions and characteristic SBMA-like neurogenic phenotypes. A single intracerebroventricular administration of the antisense oligonucleotides in the presymptomatic phase efficiently suppressed the mutant gene expression in the CNS, and delayed the onset and progression of motor dysfunction, improved body weight gain and survival with the amelioration of neuronal histopathology in motor units such as spinal motor neurons, neuromuscular junctions and skeletal muscle. These findings highlight the importance of the neurotoxicity of mutant AR protein in motor neurons as a therapeutic target. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Rescue of Pompe disease in mice by AAV-mediated liver delivery of secretable acid α-glucosidase

PubMed Central

Puzzo, Francesco; Colella, Pasqualina; Biferi, Maria G.; Bali, Deeksha; Paulk, Nicole K.; Vidal, Patrice; Collaud, Fanny; Simon-Sola, Marcelo; Charles, Severine; Hardet, Romain; Leborgne, Christian; Meliani, Amine; Cohen-Tannoudji, Mathilde; Astord, Stephanie; Gjata, Bernard; Sellier, Pauline; van Wittenberghe, Laetitia; Vignaud, Alban; Boisgerault, Florence; Barkats, Martine; Laforet, Pascal; Kay, Mark A.; Koeberl, Dwight D.; Ronzitti, Giuseppe; Mingozzi, Federico

2018-01-01

Glycogen storage disease type II or Pompe disease is a severe neuromuscular disorder caused by mutations in the lysosomal enzyme, acid α-glucosidase (GAA), which result in pathological accumulation of glycogen throughout the body. Enzyme replacement therapy is available for Pompe disease; however, it has limited efficacy, has high immunogenicity, and fails to correct pathological glycogen accumulation in nervous tissue and skeletal muscle. Using bioinformatics analysis and protein engineering, we developed transgenes encoding GAA that could be expressed and secreted by hepatocytes. Then, we used adeno-associated virus (AAV) vectors optimized for hepatic expression to deliver the GAA transgenes to Gaa knockout (Gaa−/−) mice, a model of Pompe disease. Therapeutic gene transfer to the liver rescued glycogen accumulation in muscle and the central nervous system, and ameliorated cardiac hypertrophy as well as muscle and respiratory dysfunction in the Gaa−/− mice; mouse survival was also increased. Secretable GAA showed improved therapeutic efficacy and lower immunogenicity compared to nonengineered GAA. Scale-up to nonhuman primates, and modeling of GAA expression in primary human hepatocytes using hepatotropic AAV vectors, demonstrated the therapeutic potential of AAV vector–mediated liver expression of secretable GAA for treating pathological glycogen accumulation in multiple tissues in Pompe disease. PMID:29187643

Pharmacology of a Central Nervous System Delivered 2′-O-Methoxyethyl–Modified Survival of Motor Neuron Splicing Oligonucleotide in Mice and Nonhuman Primates

PubMed Central

Chun, Seung J.; Norris, Daniel A.; Hung, Gene; Lee, Sam; Matson, John; Fey, Robert A.; Gaus, Hans; Hua, Yimin; Grundy, John S.; Krainer, Adrian R.; Henry, Scott P.; Bennett, C. Frank

2014-01-01

Spinal muscular atrophy (SMA) is a debilitating neuromuscular disease caused by the loss of survival of motor neuron (SMN) protein. Previously, we demonstrated that ISIS 396443, an antisense oligonucleotide (ASO) targeted to the SMN2 pre-mRNA, is a potent inducer of SMN2 exon 7 inclusion and SMN protein expression, and improves function and survival of mild and severe SMA mouse models. Here, we demonstrate that ISIS 396443 is the most potent ASO in central nervous system (CNS) tissues of adult mice, compared with several other chemically modified ASOs. We evaluated methods of ISIS 396443 delivery to the CNS and characterized its pharmacokinetics and pharmacodynamics in rodents and nonhuman primates (NHPs). Intracerebroventricular bolus injection is a more efficient method of delivering ISIS 396443 to the CNS of rodents, compared with i.c.v. infusion. For both methods of delivery, the duration of ISIS 396443–mediated SMN2 splicing correction is long lasting, with maximal effects still observed 6 months after treatment discontinuation. Administration of ISIS 396443 to the CNS of NHPs by a single intrathecal bolus injection results in widespread distribution throughout the spinal cord. Based upon these preclinical studies, we have advanced ISIS 396443 into clinical development. PMID:24784568

Orbitrap mass spectrometry characterization of hybrid chondroitin/dermatan sulfate hexasaccharide domains expressed in brain.

PubMed

Robu, Adrian C; Popescu, Laurentiu; Munteanu, Cristian V A; Seidler, Daniela G; Zamfir, Alina D

2015-09-15

In the central nervous system, chondroitin/dermatan sulfate (CS/DS) glycosaminoglycans (GAGs) modulate neurotrophic effects and glial cell maturation during brain development. Previous reports revealed that GAG composition could be responsible for CS/DS activities in brain. In this work, for the structural characterization of DS- and CS-rich domains in hybrid GAG chains extracted from neural tissue, we have developed an advanced approach based on high-resolution mass spectrometry (MS) using nanoelectrospray ionization Orbitrap in the negative ion mode. Our high-resolution MS and multistage MS approach was developed and applied to hexasaccharides obtained from 4- and 14-week-old mouse brains by GAG digestion with chondroitin B and in parallel with AC I lyase. The expression of DS- and CS-rich domains in the two tissues was assessed comparatively. The analyses indicated an age-related structural variability of the CS/DS motifs. The older brain was found to contain more structures and a higher sulfation of DS-rich regions, whereas the younger brain was found to be characterized by a higher sulfation of CS-rich regions. By multistage MS using collision-induced dissociation, we also demonstrated the incidence in mouse brain of an atypical [4,5-Δ-GlcAGalNAc(IdoAGalNAc)2], presenting a bisulfated CS disaccharide formed by 3-O-sulfate-4,5-Δ-GlcA and 6-O-sulfate-GalNAc moieties. Copyright © 2015 Elsevier Inc. All rights reserved.

BAG3 is involved in neuronal differentiation and migration.

PubMed

Santoro, Antonietta; Nicolin, Vanessa; Florenzano, Fulvio; Rosati, Alessandra; Capunzo, Mario; Nori, Stefania L

2017-05-01

Bcl2-associated athanogene 3 (BAG3) protein belongs to the family of co-chaperones interacting with several heat shock proteins. It plays a key role in protein quality control and mediates the clearance of misfolded proteins. Little is known about the expression and cellular localization of BAG3 during nervous system development and differentiation. Therefore, we analyze the subcellular distribution and expression of BAG3 in nerve-growth-factor-induced neurite outgrowth in PC12 cells and in developing and adult cortex of mouse brain. In differentiated PC12 cells, BAG3 was localized mainly in the neuritic domain rather than the cell body, whereas in control cells, it appeared to be confined to the cytoplasm near the nuclear membrane. Interestingly, the change of BAG3 localization during neuronal differentiation was associated only with a slight increase in total BAG3 expression. These data were coroborated by transmission electron microscopy showing that BAG3 was confined mainly within large dense-core vesicles of the axon in differentiated PC12 cells. In mouse developing cortex, BAG3 appeared to be intensely expressed in cellular processes of migrating cells, whereas in adult brain, a diffuse expression of low to medium intensity was detected in neuronal cell bodies. These findings suggest that BAG3 expression is required for neuronal differentiation and migration and that its role is linked to a change in its distribution pattern rather than to an increase in its protein expression levels.

Mouse d-Amino-Acid Oxidase: Distribution and Physiological Substrates

PubMed Central

Koga, Reiko; Miyoshi, Yurika; Sakaue, Hiroaki; Hamase, Kenji; Konno, Ryuichi

2017-01-01

d-Amino-acid oxidase (DAO) catalyzes the oxidative deamination of d-amino acids. DAO is present in a wide variety of organisms and has important roles. Here, we review the distribution and physiological substrates of mouse DAO. Mouse DAO is present in the kidney, brain, and spinal cord, like DAOs in other mammals. However, in contrast to other animals, it is not present in the mouse liver. Recently, DAO has been detected in the neutrophils, retina, and small intestine in mice. To determine the physiological substrates of mouse DAO, mutant mice lacking DAO activity are helpful. As DAO has wide substrate specificity and degrades various d-amino acids, many d-amino acids accumulate in the tissues and body fluids of the mutant mice. These amino acids are d-methionine, d-alanine, d-serine, d-leucine, d-proline, d-phenylalanine, d-tyrosine, and d-citrulline. Even in wild-type mice, administration of DAO inhibitors elevates D-serine levels in the plasma and brain. Among the above d-amino acids, the main physiological substrates of mouse DAO are d-alanine and d-serine. These two d-amino acids are most abundant in the tissues and body fluids of mice. d-Alanine derives from bacteria and produces bactericidal reactive oxygen species by the action of DAO. d-Serine is synthesized by serine racemase and is present especially in the central nervous system, where it serves as a neuromodulator. DAO is responsible for the metabolism of d-serine. Since DAO has been implicated in the etiology of neuropsychiatric diseases, mouse DAO has been used as a representative model. Recent reports, however, suggest that mouse DAO is different from human DAO with respect to important properties. PMID:29255714

TOX3 regulates neural progenitor identity.

PubMed

Sahu, Sanjeeb Kumar; Fritz, Alina; Tiwari, Neha; Kovacs, Zsuzsa; Pouya, Alireza; Wüllner, Verena; Bora, Pablo; Schacht, Teresa; Baumgart, Jan; Peron, Sophie; Berninger, Benedikt; Tiwari, Vijay K; Methner, Axel

2016-07-01

The human genomic locus for the transcription factor TOX3 has been implicated in susceptibility to restless legs syndrome and breast cancer in genome-wide association studies, but the physiological role of TOX3 remains largely unknown. We found Tox3 to be predominantly expressed in the developing mouse brain with a peak at embryonic day E14 where it co-localizes with the neural stem and progenitor markers Nestin and Sox2 in radial glia of the ventricular zone and intermediate progenitors of the subventricular zone. Tox3 is also expressed in neural progenitor cells obtained from the ganglionic eminence of E15 mice that express Nestin, and it specifically binds the Nestin promoter in chromatin immunoprecipitation assays. In line with this, over-expression of Tox3 increased Nestin promoter activity, which was cooperatively enhanced by treatment with the stem cell self-renewal promoting Notch ligand Jagged and repressed by pharmacological inhibition of Notch signaling. Knockdown of Tox3 in the subventricular zone of E12.5 mouse embryos by in utero electroporation of Tox3 shRNA revealed a reduced Nestin expression and decreased proliferation at E14 and a reduced migration to the cortical plate in E16 embryos in electroporated cells. Together, these results argue for a role of Tox3 in the development of the nervous system. Copyright © 2016 Elsevier B.V. All rights reserved.

Neurogenin3 restricts serotonergic neuron differentiation to the hindbrain.

PubMed

Carcagno, Abel L; Di Bella, Daniela J; Goulding, Martyn; Guillemot, Francois; Lanuza, Guillermo M

2014-11-12

The development of the nervous system is critically dependent on the production of functionally diverse neuronal cell types at their correct locations. In the embryonic neural tube, dorsoventral signaling has emerged as a fundamental mechanism for generating neuronal diversity. In contrast, far less is known about how different neuronal cell types are organized along the rostrocaudal axis. In the developing mouse and chick neural tube, hindbrain serotonergic neurons and spinal glutamatergic V3 interneurons are produced from ventral p3 progenitors, which possess a common transcriptional identity but are confined to distinct anterior-posterior territories. In this study, we show that the expression of the transcription factor Neurogenin3 (Neurog3) in the spinal cord controls the correct specification of p3-derived neurons. Gain- and loss-of-function manipulations in the chick and mouse embryo show that Neurog3 switches ventral progenitors from a serotonergic to V3 differentiation program by repressing Ascl1 in spinal p3 progenitors through a mechanism dependent on Hes proteins. In this way, Neurog3 establishes the posterior boundary of the serotonergic system by actively suppressing serotonergic specification in the spinal cord. These results explain how equivalent p3 progenitors within the hindbrain and the spinal cord produce functionally distinct neuron cell types. Copyright © 2014 the authors 0270-6474/14/3415223-11$15.00/0.

Selective Constraints on Coding Sequences of Nervous System Genes Are a Major Determinant of Duplicate Gene Retention in Vertebrates.

PubMed

Roux, Julien; Liu, Jialin; Robinson-Rechavi, Marc

2017-11-01

The evolutionary history of vertebrates is marked by three ancient whole-genome duplications: two successive rounds in the ancestor of vertebrates, and a third one specific to teleost fishes. Biased loss of most duplicates enriched the genome for specific genes, such as slow evolving genes, but this selective retention process is not well understood. To understand what drives the long-term preservation of duplicate genes, we characterized duplicated genes in terms of their expression patterns. We used a new method of expression enrichment analysis, TopAnat, applied to in situ hybridization data from thousands of genes from zebrafish and mouse. We showed that the presence of expression in the nervous system is a good predictor of a higher rate of retention of duplicate genes after whole-genome duplication. Further analyses suggest that purifying selection against the toxic effects of misfolded or misinteracting proteins, which is particularly strong in nonrenewing neural tissues, likely constrains the evolution of coding sequences of nervous system genes, leading indirectly to the preservation of duplicate genes after whole-genome duplication. Whole-genome duplications thus greatly contributed to the expansion of the toolkit of genes available for the evolution of profound novelties of the nervous system at the base of the vertebrate radiation. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Neuron-specific membrane glycoproteins promoting neurite fasciculation in Aplysia californica

PubMed Central

1990-01-01

We have generated a library of mouse monoclonal antibodies against membrane proteins of the nervous system of the marine snail Aplysia californica. Two of these antibodies, 4E8 and 3D9, recognize a group of membrane glycoproteins with molecular masses of 100-150 kD. We have called these proteins ap100, from the molecular mass of the most abundant species. Based on Western blots, these proteins appear to be specific for the nervous system. They are enriched in the neuropil of central nervous system ganglia, and are present on the surface of neurites and growth cones of neurons in culture. They are not expressed on the surface of nonneuronal cells. Staining of living cells with fluorescently labeled mAb demonstrates that the epitope(s) are on the outside of the cell. The antibodies against the proteins defasciculate growing axons and alter the morphology of growth cones, but affect much less adhesion between neuritic shafts. In addition, the level of expression of these molecules appears to correlate with the degree of fasciculation of neurites. These observations suggest that the ap100 proteins are cell adhesion molecules that play a role in axon growth in the nervous system of Aplysia. The fact that they are enriched in the neuropil and possibly in varicosities suggest that they may also be relevant for the structure of mature synapses. PMID:2277077

Expression profile of Lgi1 gene in mouse brain during development.

PubMed

Ribeiro, Patrícia A O; Sbragia, Lourenço; Gilioli, Rovilson; Langone, Francesco; Conte, Fábio F; Lopes-Cendes, Iscia

2008-07-01

Mutations in LGI1 were described in patients with autosomal dominant partial epilepsy with auditory features (ADPEAF), and recent clinical findings have implicated LGI1 in human brain development. However, the precise role of LGI1 in epileptogenesis remains largely unknown. The objective of this study was to determine the expression pattern of Lgi1 in mice brain during development and in adult animals. Real-time polymerase chain reaction (PCR) quantification and Western blot experiments showed a relative low expression during intrauterine stages, increasing until adulthood. In addition, we did not find significant differences between left and right hemispheres. The hippocampus presented higher levels of Lgi1 expression when compared to the neocortex and the cerebellum of adult animals; however, these results did not reach statistical significance. This study was the first to determine a specific profile of Lgi1 gene expression during central nervous system development, which suggests a possible inhibitory function in latter stages of development. In addition, we did not find differences in hemispheric expression that could explain the predominance of left-sided abnormalities in patients with ADPEAF.

Anxiety and Depression: Mouse Genetics and Pharmacological Approaches to the Role of GABAA Receptor Subtypes

PubMed Central

Smith, Kiersten S.; Rudolph, Uwe

2012-01-01

GABAA receptors mediate fast synaptic inhibitory neurotransmission throughout the central nervous system. Recent work indicates a role for GABAA receptors in physiologically modulating anxiety and depression levels. In this review, we summarize research that led to the identification of the essential role of GABAA receptors in counteracting trait anxiety and depression-related behaviors, and research aimed at identifying individual GABAA receptor subtypes involved in physiological and pharmacological modulation of emotions. PMID:21810433

Will PEDF Therapy Reverse Chronic Demyelination and Prevent Axon Loss in a Murine Model of Progressive Multiple Sclerosis

DTIC Science & Technology

2015-12-01

Multiple Sclerosis ? PRINCIPAL INVESTIGATOR: David Pleasure MD CONTRACTING ORGANIZATION: University of California Davis, CA 95618 REPORT DATE...Murine Model of Progressive Multiple Sclerosis ? 5b. GRANT NUMBER W81XWH-12-1-0566 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) David Pleasure MD 5d...enhance central nervous system (CNS) remyelination and preserve CNS axons in mouse models of multiple sclerosis models. After determining the dosage of

Expression of Histone Deacetylases in Cellular Compartments of the Mouse Brain and the Effects of Ischemia

PubMed Central

Bachleda, Amelia; Morrison, Richard S.; Murphy, Sean P.

2011-01-01

Drugs that inhibit specific histone deacetylase (HDAC) activities have enormous potential in preventing the consequences of acute injury to the nervous system and in allaying neurodegeneration. However, very little is known about the expression pattern of the HDACs in the central nervous system (CNS). Identifying the cell types that express HDACs in the CNS is important for determining therapeutic targets for HDAC inhibitors and evaluating potential side effects. We characterized the cellular expression of HDACs 1–3, and HDACs 4 and 6, in the adult mouse brain in the cingulate cortex, parietal cortex, dentate gyrus, and CA1 regions of the hippocampus and subcortical white matter. Expression of class I HDACs showed a cell-and region-specific pattern. Transient focal ischemia induced by temporary middle cerebral artery occlusion, or global ischemia induced by in vitro oxygen–glucose deprivation, altered the extent of HDAC expression in a region- and cell-specific manner. The pan-HDAC inhibitor, SAHA, reduced ischemia-induced alterations in HDACs. The results suggest that in addition to promoting epigenetic changes in transcriptional activity in the nucleus of neurons and glia, HDACs may also have non-transcriptional actions in axons and the distant processes of glial cells and may significantly modulate the response to injury in a cell- and region-specific manner. PMID:21966324

Nonlinear optical techniques for imaging and manipulating the mouse central nervous system

NASA Astrophysics Data System (ADS)

Farrar, Matthew John

The spinal cord of vertebrates serves as the conduit for somatosensory information and motor control, as well as being the locus of neural circuits that govern fast reflexes and patterned behaviors, such as walking in mammals or swimming in fish. Consequently, pathologies of the spinal cord -such as spinal cord injury (SCI)- lead to loss of motor control and sensory perception, with accompanying decline in life expectancy and quality of life. Despite the devastating effects of these diseases, few therapies exist to substantially ameliorate patient outcome. In part, studies of spinal cord pathology have been limited by the inability to perform in vivo imaging at the level of cellular processes. The focus of this thesis is to present the underlying theory for and demonstration of novel multi-photon microscopy (MPM) and optical manipulation techniques as they apply to studies the mouse central nervous system (CNS), with an emphasis on the spinal cord. The scientific findings which have resulted from the implementation of these techniques are also presented. In particular, we have demonstrated that third harmonic generation is a dye-free method of imaging CNS myelin, a fundamental constituent of the spinal cord that is difficult to label using exogenous dyes and/or transgenic constructs. Since gaining optical access to the spinal cord is a prerequisite for spinal cord imaging, we review our development of a novel spinal cord imaging chamber and surgical procedure which allowed us to image for multiple weeks following implantation without the need for repeated surgeries. We also have used MPM to characterize spinal venous blood flow before and after point occlusions. We review a novel nonlinear microscopy technique that may serve to show optical interfaces in three dimensions inside scattering tissue. Finally, we discuss a model and show results of optoporation, a means of transfecting cells with genetic constructs. Brief reviews of MPM and SCI are also presented.

Quantitative Analyses of Synergistic Responses between Cannabidiol and DNA-Damaging Agents on the Proliferation and Viability of Glioblastoma and Neural Progenitor Cells in Culture

PubMed Central

Deng, Liting; Ng, Lindsay; Ozawa, Tatsuya

2017-01-01

Evidence suggests that the nonpsychotropic cannabis-derived compound, cannabidiol (CBD), has antineoplastic activity in multiple types of cancers, including glioblastoma multiforme (GBM). DNA-damaging agents remain the main standard of care treatment available for patients diagnosed with GBM. Here we studied the antiproliferative and cell-killing activity of CBD alone and in combination with DNA-damaging agents (temozolomide, carmustine, or cisplatin) in several human GBM cell lines and in mouse primary GBM cells in cultures. This activity was also studied in mouse neural progenitor cells (NPCs) in culture to assess for potential central nervous system toxicity. We found that CBD induced a dose-dependent reduction of both proliferation and viability of all cells with similar potencies, suggesting no preferential activity for cancer cells. Hill plot analysis indicates an allosteric mechanism of action triggered by CBD in all cells. Cotreatment regimens combining CBD and DNA-damaging agents produced synergistic antiproliferating and cell-killing responses over a limited range of concentrations in all human GBM cell lines and mouse GBM cells as well as in mouse NPCs. Remarkably, antagonistic responses occurred at low concentrations in select human GBM cell lines and in mouse GBM cells. Our study suggests limited synergistic activity when combining CBD and DNA-damaging agents in treating GBM cells, along with little to no therapeutic window when considering NPCs. PMID:27821713

Development of electrocardiogram intervals during growth of FVB/N neonate mice

PubMed Central

2010-01-01

Background Electrocardiography remains the best diagnostic tool and therapeutic biomarker for a spectrum of pediatric diseases involving cardiac or autonomic nervous system defects. As genetic links to these disorders are established and transgenic mouse models produced in efforts to understand and treat them, there is a surprising lack of information on electrocardiograms (ECGs) and ECG abnormalities in neonate mice. This is likely due to the trauma and anaesthesia required of many legacy approaches to ECG recording in mice, exacerbated by the fragility of many mutant neonates. Here, we use a non-invasive system to characterize development of the heart rate and electrocardiogram throughout the growth of conscious neonate FVB/N mice. Results We examine ECG waveforms as early as two days after birth. At this point males and females demonstrate comparable heart rates that are 50% lower than adult mice. Neonatal mice exhibit very low heart rate variability. Within 12 days of birth PR, QRS and QTc interval durations are near adult values while heart rate continues to increase until weaning. Upon weaning FVB/N females quickly develop slower heart rates than males, though PR intervals are comparable between sexes until a later age. This suggests separate developmental events may contribute to these gender differences in electrocardiography. Conclusions We provide insight with a new level of detail to the natural course of heart rate establishment in neonate mice. ECG can now be conveniently and repeatedly used in neonatal mice. This should serve to be of broad utility, facilitating further investigations into development of a diverse group of diseases and therapeutics in preclinical mouse studies. PMID:20735846

Localization of laminin B1 mRNA in retinal ganglion cells by in situ hybridization

PubMed Central

1990-01-01

In the nervous system, neuronal migration and axonal growth are dependent on specific interactions with extracellular matrix proteins. During development of the vertebrate retina, ganglion cell axons extend along the internal limiting (basement) membrane and form the optic nerve. Laminin, a major component of basement membranes, is known to be present in the internal limiting membrane, and might be involved in the growth of ganglion cell axons. The identity of the cells that produce retinal laminin, however, has not been established. In the present study, we have used in situ hybridization to localize the sites of laminin B1 mRNA synthesis in the developing mouse retina. Our results show that there are at least two principal sites of laminin B1 mRNA synthesis: (a) the hyaloid vessels and the lens during the period of major axonal outgrowth, and (b) the retinal ganglion cells at later development stages. Muller (glial) cells, the major class of nonneuronal cells in the retina, do not appear to express laminin B1 mRNA either during development or in the adult retina. In Northern blots, we found a single transcript of approximately 6-kb size that encodes the laminin B1 chain in the retina. Moreover, laminin B1 mRNA level was four- to fivefold higher in the postnatal retina compared to that in the adult. Our results show that in addition to nonneuronal cells, retinal ganglion cells also synthesize laminin. The function of laminin in postnatal retinas, however, remains to be elucidated. Nevertheless, our findings raise the possibility that neurons in other parts of the nervous system might also synthesize extracellular matrix proteins. PMID:2351694

Mosaic expression of Atrx in the mouse central nervous system causes memory deficits

PubMed Central

Tamming, Renee J.; Siu, Jennifer R.; Jiang, Yan; Prado, Marco A. M.; Beier, Frank

2017-01-01

ABSTRACT The rapid modulation of chromatin organization is thought to play a crucial role in cognitive processes such as memory consolidation. This is supported in part by the dysregulation of many chromatin-remodelling proteins in neurodevelopmental and psychiatric disorders. A key example is ATRX, an X-linked gene commonly mutated in individuals with syndromic and nonsyndromic intellectual disability. The consequences of Atrx inactivation for learning and memory have been difficult to evaluate because of the early lethality of hemizygous-null animals. In this study, we evaluated the outcome of brain-specific Atrx deletion in heterozygous female mice. These mice exhibit a mosaic pattern of ATRX protein expression in the central nervous system attributable to the location of the gene on the X chromosome. Although the hemizygous male mice die soon after birth, heterozygous females survive to adulthood. Body growth is stunted in these animals, and they have low circulating concentrations of insulin growth factor 1. In addition, they are impaired in spatial, contextual fear and novel object recognition memory. Our findings demonstrate that mosaic loss of ATRX expression in the central nervous system leads to endocrine defects and decreased body size and has a negative impact on learning and memory. PMID:28093507

Identification of Genes from the Fungal Pathogen Cryptococcus neoformans Related to Transmigration into the Central Nervous System

PubMed Central

Tseng, Hsiang-Kuang; Liu, Chang-Pan; Price, Michael S.; Jong, Ambrose Y.; Chang, Jui-Chih; Toffaletti, Dena L.; Betancourt-Quiroz, Marisol; Frazzitta, Aubrey E.; Cho, Wen-Long; Perfect, John R.

2012-01-01

Background A mouse brain transmigration assessment (MBTA) was created to investigate the central nervous system (CNS) pathogenesis of cryptococcal meningoencephalitis. Methodology/Principal Findings Two cryptococcal mutants were identified from a pool of 109 pre-selected mutants that were signature-tagged with the nourseothricin acetyltransferase (NAT) resistance cassette. These two mutants displayed abnormal transmigration into the central nervous system. One mutant displaying decreased transmigration contains a null mutation in the putative FNX1 gene, whereas the other mutant possessing a null mutation in the putative RUB1 gene exhibited increased transmigration into the brain. Two macrophage adhesion-defective mutants in the pool, 12F1 and 3C9, showed reduced phagocytosis by macrophages, but displayed no defects in CNS entry suggesting that transit within macrophages (the “Trojan horse” model of CNS entry) is not the primary mechanism for C. neoformans migration into the CNS in this MBTA. Conclusions/Significance This research design provides a new strategy for genetic impact studies on how Cryptococcus passes through the blood-brain barrier (BBB), and the specific isolated mutants in this assay support a transcellular mechanism of CNS entry. PMID:23028773

Functional lacrimal gland regeneration by transplantation of a bioengineered organ germ

PubMed Central

Hirayama, Masatoshi; Ogawa, Miho; Oshima, Masamitsu; Sekine, Yurie; Ishida, Kentaro; Yamashita, Kentaro; Ikeda, Kazutaka; Shimmura, Shigeto; Kawakita, Tetsuya; Tsubota, Kazuo; Tsuji, Takashi

2013-01-01

The lacrimal gland has a multifaceted role in maintaining a homeostatic microenvironment for a healthy ocular surface via tear secretion. Dry-eye disease, which is caused by lacrimal gland dysfunction, is one of the most prevalent eye diseases that cause corneal epithelial damage and results in significant loss of vision and a reduction in the quality of life. Here we demonstrate orthotopic transplantation of bioengineered lacrimal gland germs into adult mice with an extra-orbital lacrimal gland defect, a mouse model that mimics the corneal epithelial damage caused by lacrimal gland dysfunction. The bioengineered lacrimal gland germs and harderian gland germs both develop in vivo and achieve sufficient physiological functionality, including tear production in response to nervous stimulation and ocular surface protection. This study demonstrates the potential for bioengineered organ replacement to functionally restore the lacrimal gland. PMID:24084941

EMBRYOLOGY OF THE LITTLE AND BAGG X-RAYED MOUSE STOCK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, T.C.

1959-12-01

The morphology and development of the many defects in mice of the Little and Bagg x-rayed stock have been reinvestigated in an attempt to resolve the conflicts in the findings of earlier investigators. The observation that blebs occur on pseudencephalic embryos is incompatible with Bonnevie's hypothesis that they originate as cerebrospinal fluid in the myelencephalon; other observations support Plagens' hypothesis that the blebs originate as mesenchymal intercellular fluid. No unitary gene action was found. Four pedigrees of causes were constructed covering, respectively, defects of the central nervous system, bleb- induced lesions and defects of the body wall, morphological defects ofmore » the hind limbs, and defects of the urogenital system; there were cross-correlations between defects in the first three pedigrees, but the underlying mechanisms were not identified. (auth)« less

In-depth phenotyping of lymphoblastoid cells suggests selective cellular vulnerability in Marinesco-Sjögren syndrome

PubMed Central

Kollipara, Laxmikanth; Buchkremer, Stephan; Coraspe, José Andrés González; Hathazi, Denisa; Senderek, Jan; Weis, Joachim; Zahedi, René P.; Roos, Andreas

2017-01-01

SIL1 is a ubiquitous protein of the Endoplasmic Reticulum (ER) acting as a co-chaperone for the ER-resident chaperone, BiP. Recessive mutations of the corresponding gene lead to vulnerability of skeletal muscle and central nervous system in man (Marinesco-Sjögren syndrome; MSS) and mouse. However, it is still unclear how loss of ubiquitous SIL1 leads to selective vulnerability of the nervous system and skeletal muscle whereas other cells and organs are protected from clinical manifestations. In this study we aimed to disentangle proteins participating in selective vulnerability of SIL1-deficient cells and tissues: morphological examination of MSS patient-derived lymphoblastoid cells revealed altered organelle structures (ER, nucleus and mitochondria) thus showing subclinical vulnerability. To correlate structural perturbations with biochemical changes and to identify proteins potentially preventing phenotypical manifestation, proteomic studies have been carried out. Results of proteomic profiling are in line with the morphological findings and show affection of nuclear, mitochondrial and cytoskeletal proteins as well as of such responsible for cellular viability. Moreover, expression patterns of proteins known to be involved in neuromuscular disorders or in development and function of the nervous system were altered. Paradigmatic findings were confirmed by immunohistochemistry of splenic lymphocytes and the cerebellum of SIL1-deficient mice. Ataxin-10, identified with increased abundance in our proteome profile, is necessary for the neuronal survival but also controls muscle fiber apoptosis, thus declaring this protein as a plausible candidate for selective tissue vulnerability. Our combined results provide first insights into the molecular causes of selective cell and tissue vulnerability defining the MSS phenotype. PMID:28978133

Brain Ischemia Induces Diversified Neuroantigen-Specific T-Cell Responses That Exacerbate Brain Injury.

PubMed

Jin, Wei-Na; Gonzales, Rayna; Feng, Yan; Wood, Kristofer; Chai, Zhi; Dong, Jing-Fei; La Cava, Antonio; Shi, Fu-Dong; Liu, Qiang

2018-06-01

Autoimmune responses can occur when antigens from the central nervous system are presented to lymphocytes in the periphery or central nervous system in several neurological diseases. However, whether autoimmune responses emerge after brain ischemia and their impact on clinical outcomes remains controversial. We hypothesized that brain ischemia facilitates the genesis of autoimmunity and aggravates ischemic brain injury. Using a mouse strain that harbors a transgenic T-cell receptor to a central nervous system antigen, MOG 35-55 (myelin oligodendrocyte glycoprotein) epitope (2D2), we determined the anatomic location and involvement of antigen-presenting cells in the development of T-cell reactivity after brain ischemia and how T-cell reactivity impacts stroke outcome. Transient middle cerebral artery occlusion and photothrombotic stroke models were used in this study. We also quantified the presence and status of T cells from brain slices of ischemic patients. By coupling transfer of labeled MOG 35-55 -specific (2D2) T cells with tetramer tracking, we show an expansion in reactivity of 2D2 T cells to MOG 91-108 and MOG 103-125 in transient middle cerebral artery occlusion and photothrombotic stroke models. This reactivity and T-cell activation first occur locally in the brain after ischemia. Also, microglia act as antigen-presenting cells that effectively present MOG antigens, and depletion of microglia ablates expansion of 2D2 reactive T cells. Notably, the adoptive transfer of neuroantigen-experienced 2D2 T cells exacerbates Th1/Th17 responses and brain injury. Finally, T-cell activation and MOG-specific T cells are present in the brain of patients with ischemic stroke. Our findings suggest that brain ischemia activates and diversifies T-cell responses locally, which exacerbates ischemic brain injury. © 2018 The Authors.

Enteric glia.

PubMed

Rühl, A; Nasser, Y; Sharkey, K A

2004-04-01

The enteric nervous system is composed of both enteric neurones and enteric glia. Enteric glial cells were first described by Dogiel and are now known to outnumber neurones approximately 4 : 1. In the past, these cells were assumed to subserve a largely supportive role; however, recent evidence indicates that enteric glial cells may play a more active role in the control of gut function. In transgenic mouse models, where enteric glial cells are selectively ablated, the loss of glia results in intestinal inflammation and disruption of the epithelial barrier. Enteric glia are activated specifically by inflammatory insults and may contribute actively to inflammatory pathology via antigen presentation and cytokine synthesis. Enteric glia also express receptors for neurotransmitters and so may serve as intermediaries in enteric neurotransmission. Thus, enteric glia may serve as a link between the nervous and immune systems of the gut and may also have an important role in maintaining the integrity of the mucosal barrier and in other aspects of intestinal homeostasis.

Lifespan analysis of brain development, gene expression and behavioral phenotypes in the Ts1Cje, Ts65Dn and Dp(16)1/Yey mouse models of Down syndrome.

PubMed

Aziz, Nadine M; Guedj, Faycal; Pennings, Jeroen L A; Olmos-Serrano, Jose Luis; Siegel, Ashley; Haydar, Tarik F; Bianchi, Diana W

2018-06-12

Down syndrome (DS) results from triplication of human chromosome 21. Neuropathological hallmarks of DS include atypical central nervous system development that manifests prenatally and extends throughout life. As a result, individuals with DS exhibit cognitive and motor deficits, and have delays in achieving developmental milestones. To determine whether different mouse models of DS recapitulate the human prenatal and postnatal phenotypes, here, we directly compared brain histogenesis, gene expression and behavior over the lifespan of three cytogenetically distinct mouse models of DS: Ts1Cje, Ts65Dn and Dp(16)1/Yey. Histological data indicated that Ts65Dn mice were the most consistently affected with respect to somatic growth, neurogenesis and brain morphogenesis. Embryonic and adult gene expression results showed that Ts1Cje and Ts65Dn brains had considerably more differentially expressed (DEX) genes compared with Dp(16)1/Yey mice, despite the larger number of triplicated genes in the latter model. In addition, DEX genes showed little overlap in identity and chromosomal distribution in the three models, leading to dissimilarities in affected functional pathways. Perinatal and adult behavioral testing also highlighted differences among the models in their abilities to achieve various developmental milestones and perform hippocampal- and motor-based tasks. Interestingly, Dp(16)1/Yey mice showed no abnormalities in prenatal brain phenotypes, yet they manifested behavioral deficits starting at postnatal day 15 that continued through adulthood. In contrast, Ts1Cje mice showed mildly abnormal embryonic brain phenotypes, but only select behavioral deficits as neonates and adults. Altogether, our data showed widespread and unexpected fundamental differences in behavioral, gene expression and brain development phenotypes between these three mouse models. Our findings illustrate unique limitations of each model when studying aspects of brain development and function in DS. This work helps to inform model selection in future studies investigating how observed neurodevelopmental abnormalities arise, how they contribute to cognitive impairment, and when testing therapeutic molecules to ameliorate the intellectual disability associated with DS.This article has an associated First Person interview with the first author of the paper. © 2018. Published by The Company of Biologists Ltd.

A family of splice variants of CstF-64 expressed in vertebrate nervous systems

PubMed Central

Shankarling, Ganesh S; Coates, Penelope W; Dass, Brinda; MacDonald, Clinton C

2009-01-01

Background Alternative splicing and polyadenylation are important mechanisms for creating the proteomic diversity necessary for the nervous system to fulfill its specialized functions. The contribution of alternative splicing to proteomic diversity in the nervous system has been well documented, whereas the role of alternative polyadenylation in this process is less well understood. Since the CstF-64 polyadenylation protein is known to be an important regulator of tissue-specific polyadenylation, we examined its expression in brain and other organs. Results We discovered several closely related splice variants of CstF-64 – collectively called βCstF-64 – that could potentially contribute to proteomic diversity in the nervous system. The βCstF-64 splice variants are found predominantly in the brains of several vertebrate species including mice and humans. The major βCstF-64 variant mRNA is generated by inclusion of two alternate exons (that we call exons 8.1 and 8.2) found between exons 8 and 9 of the CstF-64 gene, and contains an additional 147 nucleotides, encoding 49 additional amino acids. Some variants of βCstF-64 contain only the first alternate exon (exon 8.1) while other variants contain both alternate exons (8.1 and 8.2). In mice, the predominant form of βCstF-64 also contains a deletion of 78 nucleotides from exon 9, although that variant is not seen in any other species examined, including rats. Immunoblot and 2D-PAGE analyses of mouse nuclear extracts indicate that a protein corresponding to βCstF-64 is expressed in brain at approximately equal levels to CstF-64. Since βCstF-64 splice variant family members were found in the brains of all vertebrate species examined (including turtles and fish), this suggests that βCstF-64 has an evolutionarily conserved function in these animals. βCstF-64 was present in both pre- and post-natal mice and in different regions of the nervous system, suggesting an important role for βCstF-64 in neural gene expression throughout development. Finally, experiments in representative cell lines suggest that βCstF-64 is expressed in neurons but not glia. Conclusion This is the first report of a family of splice variants encoding a key polyadenylation protein that is expressed in a nervous system-specific manner. We propose that βCstF-64 contributes to proteomic diversity by regulating alternative polyadenylation of neural mRNAs. PMID:19284619

Inhibition of N-type Ca2+ channels ameliorates an imbalance in cardiac autonomic nerve activity and prevents lethal arrhythmias in mice with heart failure.

PubMed

Yamada, Yuko; Kinoshita, Hideyuki; Kuwahara, Koichiro; Nakagawa, Yasuaki; Kuwabara, Yoshihiro; Minami, Takeya; Yamada, Chinatsu; Shibata, Junko; Nakao, Kazuhiro; Cho, Kosai; Arai, Yuji; Yasuno, Shinji; Nishikimi, Toshio; Ueshima, Kenji; Kamakura, Shiro; Nishida, Motohiro; Kiyonaka, Shigeki; Mori, Yasuo; Kimura, Takeshi; Kangawa, Kenji; Nakao, Kazuwa

2014-10-01

Dysregulation of autonomic nervous system activity can trigger ventricular arrhythmias and sudden death in patients with heart failure. N-type Ca(2+) channels (NCCs) play an important role in sympathetic nervous system activation by regulating the calcium entry that triggers release of neurotransmitters from peripheral sympathetic nerve terminals. We have investigated the ability of NCC blockade to prevent lethal arrhythmias associated with heart failure. We compared the effects of cilnidipine, a dual N- and L-type Ca(2+) channel blocker, with those of nitrendipine, a selective L-type Ca(2+) channel blocker, in transgenic mice expressing a cardiac-specific, dominant-negative form of neuron-restrictive silencer factor (dnNRSF-Tg). In this mouse model of dilated cardiomyopathy leading to sudden arrhythmic death, cardiac structure and function did not significantly differ among the control, cilnidipine, and nitrendipine groups. However, cilnidipine dramatically reduced arrhythmias in dnNRSF-Tg mice, significantly improving their survival rate and correcting the imbalance between cardiac sympathetic and parasympathetic nervous system activity. A β-blocker, bisoprolol, showed similar effects in these mice. Genetic titration of NCCs, achieved by crossing dnNRSF-Tg mice with mice lacking CACNA1B, which encodes the α1 subunit of NCCs, improved the survival rate. With restoration of cardiac autonomic balance, dnNRSF-Tg;CACNA1B(+/-) mice showed fewer malignant arrhythmias than dnNRSF-Tg;CACNA1B(+/+) mice. Both pharmacological blockade of NCCs and their genetic titration improved cardiac autonomic balance and prevented lethal arrhythmias in a mouse model of dilated cardiomyopathy and sudden arrhythmic death. Our findings suggest that NCC blockade is a potentially useful approach to preventing sudden death in patients with heart failure. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Functional genomics reveals an essential and specific role for Stat1 in protection of the central nervous system following herpes simplex virus corneal infection.

PubMed

Pasieka, Tracy Jo; Cilloniz, Cristian; Carter, Victoria S; Rosato, Pamela; Katze, Michael G; Leib, David A

2011-12-01

Innate immune deficiencies result in a spectrum of severe clinical outcomes following infection. In particular, there is a strong association between loss of the signal transducer and activator of transcription (Stat) pathway, breach of the blood-brain barrier (BBB), and virus-induced neuropathology. The gene signatures that characterize resistance, disease, and mortality in the virus-infected nervous system have not been defined. Herpes simplex virus type 1 (HSV-1) is commonly associated with encephalitis in humans, and humans and mice lacking Stat1 display increased susceptibility to HSV central nervous system (CNS) infections. In this study, two HSV-1 strains were used, KOS (wild type [WT]), and Δvhs, an avirulent recombinant lacking the virion host shutoff (vhs) function. In addition, two mouse strains were used: strain 129 (control) and a Stat1-deficient (Stat1(-/-)) strain. Using combinations of these virus and mouse strains, we established a model of infection resulting in three different outcomes: viral clearance without neurological disease (Δvhs infection of control mice), neurological disease followed by viral clearance (Δvhs infection of Stat1(-/-) mice and WT infection of control mice), or neurological disease followed by death (WT infection of Stat1(-/-) mice). Through the use of functional genomics on the infected brain stems, we determined gene signatures that were representative of the three infection outcomes. We demonstrated a pathological signature in the brain stem of Stat1-deficient mice characterized by upregulation of transcripts encoding chemokine receptors, inflammatory markers, neutrophil chemoattractants, leukocyte adhesion proteins, and matrix metalloproteases. Additionally, there was a greater than 100-fold increase in the inflammatory markers interleukin 1β (IL-1β) and IL-6. Consistent with this gene signature, we demonstrated profound CNS inflammation with a concomitant lethal breach of the BBB. Taken together, our results indicated an essential role for normal Stat1-dependent signaling in mediating a nonpathological immune response to viral CNS infection.

Travelling within the fetal gut: simple rules for an arduous journey

PubMed Central

2014-01-01

The complex physiology of the gastrointestinal tract is regulated by intricate neural networks embedded within the gut wall. How neural crest cells colonize the intestine to form the enteric nervous system is of great interest to developmental biologists, but also highly relevant for understanding gastrointestinal disorders. A recent paper in BMC Biology addresses this issue with live imaging of gut explants from mouse embryos. See research article: http://www.biomedcentral.com/1741-7007/12/23. PMID:25184534

Towards bridging the gap between acid-base transporters and neuronal excitability modulation

PubMed Central

Liu, Ying; Chen, Li-Ming

2014-01-01

pH homeostasis is a fundamental regulator of the function of the central nervous system. Dysfunction of acid-base transporters often results in disturbance of neuronal excitability. In a latest issue of Journal of Neuroscience, Jones et al. report that increasing intracellular bicarbonate concentration substantially stimulates the excitability of pyramidal neurons from mouse hippocampus by inhibiting KCNQ potassium channel. The finding shed important new light in understanding the molecular mechanism underlying the regulation of neuronal excitability by acid-base transporters. PMID:25755844

Experimentally induced otitis and audiogenic seizure in the mouse.

PubMed

Niaussat, M M

1977-04-15

Audiogenic seizures can be induced in genetically non-susceptible 17-day-old mice (Rb/3 strain) with various results. Priming only induces 9% of seizures, auditory insulation 3,8%, while experimental otitis leads to 79%. The hypothesis concerning disuse supersensitivity subsequent to acoustic deprivation was not confirmed by the experiment. However, modification of acoustic transmission at middle ear level induced by otitis or ear physical damage during the maturation period, exposes the upper nervous centers to intense stimulation to which the reaction is a recruiting response.

Identification of Novel Myelin-Associated CD4+ T cell Autoantigens Targeted in MS Using a High-Throughput Gene Synthesis Technology

DTIC Science & Technology

2013-10-01

epitopes from Epstein - Barr virus (EBV), Cytomegalovirus, influenza and tetanus toxoid linked to the LC3 tag were constructed and in vitro transcribed...of these proteins in the CNS, their ability to elicit MS-like disease in the mouse experimental autoimmune encephalitis model, and the presence of T...Goverman, J. 2009. Autoimmune T cell responses in the central nervous system . Nat. Rev. Immunol. 9: 393-407. 3. Jahn, O., S. Tenzer, and H. B

Antibody-based PET imaging of amyloid beta in mouse models of Alzheimer's disease

PubMed Central

Sehlin, Dag; Fang, Xiaotian T.; Cato, Linda; Antoni, Gunnar; Lannfelt, Lars; Syvänen, Stina

2016-01-01

Owing to their specificity and high-affinity binding, monoclonal antibodies have potential as positron emission tomography (PET) radioligands and are currently used to image various targets in peripheral organs. However, in the central nervous system, antibody uptake is limited by the blood–brain barrier (BBB). Here we present a PET ligand to be used for diagnosis and evaluation of treatment effects in Alzheimer's disease. The amyloid β (Aβ) antibody mAb158 is radiolabelled and conjugated to a transferrin receptor antibody to enable receptor-mediated transcytosis across the BBB. PET imaging of two different mouse models with Aβ pathology clearly visualize Aβ in the brain. The PET signal increases with age and correlates closely with brain Aβ levels. Thus, we demonstrate that antibody-based PET ligands can be successfully used for brain imaging. PMID:26892305

The HIV-1 viral protein Tat increases glutamate and decreases GABA exocytosis from human and mouse neocortical nerve endings.

PubMed

Musante, Veronica; Summa, Maria; Neri, Elisa; Puliti, Aldamaria; Godowicz, Tomasz T; Severi, Paolo; Battaglia, Giuseppe; Raiteri, Maurizio; Pittaluga, Anna

2010-08-01

Human immunodeficiency virus-1 (HIV-1)-encoded transactivator of transcription (Tat) potentiated the depolarization-evoked exocytosis of [(3)H]D-aspartate ([(3)H]D-ASP) from human neocortical terminals. The metabotropic glutamate (mGlu) 1 receptor antagonist 7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxylate ethyl ester (CPCCOEt) prevented this effect, whereas the mGlu5 receptor antagonist 2-methyl-6-(phenylethynyl) pyridine hydrochloride (MPEP) was ineffective. Western blot analysis showed that human neocortex synaptosomes possess mGlu1 and mGlu5 receptors. Tat potentiated the K(+)-evoked release of [(3)H]D-ASP or of endogenous glutamate from mouse neocortical synaptosomes in a CPCCOEt-sensitive and MPEP-insensitive manner. Deletion of mGlu1 receptors (crv4/crv4 mice) or mGlu5 receptors (mGlu5(-/-)mouse) silenced Tat effects. Tat enhanced inositol 1,4,5-trisphosphate production in human and mouse neocortical synaptosomes, consistent with the involvement of group I mGlu receptors. Tat inhibited the K(+)-evoked release of [(3)H]gamma-aminobutyric acid ([(3)H]GABA) from human synaptosomes and that of endogenous GABA or [(3)H]GABA from mouse nerve terminals; the inhibition was insensitive to CPCCOEt or MPEP. Tat-induced effects were retained by Tat(37-72) but not by Tat(48-85). In mouse neocortical slices, Tat facilitated the K(+)- and the veratridine-induced release of [(3)H]D-ASP in a CPCCOEt-sensitive manner and was ineffective in crv4/crv4 mouse slices. These observations are relevant to the comprehension of the pathophysiological effects of Tat in central nervous system and may suggest new potential therapeutic approaches to the cure of HIV-1-associated dementia.

Early Microglia Activation Precedes Photoreceptor Degeneration in a Mouse Model of CNGB1-Linked Retinitis Pigmentosa.

PubMed

Blank, Thomas; Goldmann, Tobias; Koch, Mirja; Amann, Lukas; Schön, Christian; Bonin, Michael; Pang, Shengru; Prinz, Marco; Burnet, Michael; Wagner, Johanna E; Biel, Martin; Michalakis, Stylianos

2017-01-01

Retinitis pigmentosa (RP) denotes a family of inherited blinding eye diseases characterized by progressive degeneration of rod and cone photoreceptors in the retina. In most cases, a rod-specific genetic defect results in early functional loss and degeneration of rods, which is followed by degeneration of cones and loss of daylight vision at later stages. Microglial cells, the immune cells of the central nervous system, are activated in retinas of RP patients and in several RP mouse models. However, it is still a matter of debate whether activated microglial cells may be responsible for the amplification of the typical degenerative processes. Here, we used Cngb1 -/- mice, which represent a slow degenerative mouse model of RP, to investigate the extent of microglia activation in retinal degeneration. With a combination of FACS analysis, immunohistochemistry and gene expression analysis we established that microglia in the Cngb1 -/- retina were already activated in an early, predegenerative stage of the disease. The evidence available so far suggests that early retinal microglia activation represents a first step in RP, which might initiate or accelerate photoreceptor degeneration.

Spina Bifida: Pathogenesis, Mechanisms, and Genes in Mice and Humans

PubMed Central

Abou Chaar, Mohamad K.; Ahmad-Annuar, Azlina

2017-01-01

Spina bifida is among the phenotypes of the larger condition known as neural tube defects (NTDs). It is the most common central nervous system malformation compatible with life and the second leading cause of birth defects after congenital heart defects. In this review paper, we define spina bifida and discuss the phenotypes seen in humans as described by both surgeons and embryologists in order to compare and ultimately contrast it to the leading animal model, the mouse. Our understanding of spina bifida is currently limited to the observations we make in mouse models, which reflect complete or targeted knockouts of genes, which perturb the whole gene(s) without taking into account the issue of haploinsufficiency, which is most prominent in the human spina bifida condition. We thus conclude that the need to study spina bifida in all its forms, both aperta and occulta, is more indicative of the spina bifida in surviving humans and that the measure of deterioration arising from caudal neural tube defects, more commonly known as spina bifida, must be determined by the level of the lesion both in mouse and in man. PMID:28286691

Binding of epsilon-toxin from Clostridium perfringens in the nervous system.

PubMed

Dorca-Arévalo, Jonatan; Soler-Jover, Alex; Gibert, Maryse; Popoff, Michel R; Martín-Satué, Mireia; Blasi, Juan

2008-09-18

Epsilon-toxin (epsilon-toxin), produced by Clostridium perfringens type D, is the main agent responsible for enterotoxaemia in livestock. Neurological disorders are a characteristic of the onset of toxin poisoning. Epsilon-Toxin accumulates specifically in the central nervous system, where it produces a glutamatergic-mediated excitotoxic effect. However, no detailed study of putative binding structures in the nervous tissue has been carried out to date. Here we attempt to identify specific acceptor moieties and cell targets for epsilon-toxin, not only in the mouse nervous system but also in the brains of sheep and cattle. An epsilon-toxin-GFP fusion protein was produced and used to incubate brain sections, which were then analyzed by confocal microscopy. The results clearly show specific binding of epsilon-toxin to myelin structures. epsilon-Prototoxin-GFP and epsilon-toxin-GFP, the inactive and active forms of the toxin, respectively, showed identical results. By means of pronase E treatment, we found that the binding was mainly associated to a protein component of the myelin. Myelinated peripheral nerve fibres were also stained by epsilon-toxin. Moreover, the binding to myelin was not only restricted to rodents, but was also found in humans, sheep and cattle. Curiously, in the brains of both sheep and cattle, the toxin strongly stained the vascular endothelium, a result that may explain the differences in potency and effect between species. Although the binding of epsilon-toxin to myelin does not directly explain its neurotoxic effect, this feature opens up a new line of enquiry into its mechanism of toxicity and establishes the usefulness of this toxin for the study of the mammalian nervous system.

Oligodendrocyte- and Neuron-Specific Nogo-A Restrict Dendritic Branching and Spine Density in the Adult Mouse Motor Cortex.

PubMed

Zemmar, Ajmal; Chen, Chia-Chien; Weinmann, Oliver; Kast, Brigitt; Vajda, Flora; Bozeman, James; Isaad, Noel; Zuo, Yi; Schwab, Martin E

2018-06-01

Nogo-A has been well described as a myelin-associated inhibitor of neurite outgrowth and functional neuroregeneration after central nervous system (CNS) injury. Recently, a new role of Nogo-A has been identified as a negative regulator of synaptic plasticity in the uninjured adult CNS. Nogo-A is present in neurons and oligodendrocytes. However, it is yet unclear which of these two pools regulate synaptic plasticity. To address this question we used newly generated mouse lines in which Nogo-A is specifically knocked out in (1) oligodendrocytes (oligoNogo-A KO) or (2) neurons (neuroNogo-A KO). We show that both oligodendrocyte- and neuron-specific Nogo-A KO mice have enhanced dendritic branching and spine densities in layer 2/3 cortical pyramidal neurons. These effects are compartmentalized: neuronal Nogo-A affects proximal dendrites whereas oligodendrocytic Nogo-A affects distal regions. Finally, we used two-photon laser scanning microscopy to measure the spine turnover rate of adult mouse motor cortex layer 5 cells and find that both Nogo-A KO mouse lines show enhanced spine remodeling after 4 days. Our results suggest relevant control functions of glial as well as neuronal Nogo-A for synaptic plasticity and open new possibilities for more selective and targeted plasticity enhancing strategies.

Transplanted human glial-restricted progenitors can rescue the survival of dysmyelinated mice independent of the production of mature, compact myelin.

PubMed

Lyczek, Agatha; Arnold, Antje; Zhang, Jiangyang; Campanelli, James T; Janowski, Miroslaw; Bulte, Jeff W M; Walczak, Piotr

2017-05-01

The therapeutic effect of glial progenitor transplantation in diseases of dysmyelination is currently attributed to the formation of new myelin. Using magnetic resonance imaging (MRI), we show that the therapeutic outcome in dysmyelinated shiverer mice is dependent on the extent of cell migration but not the presence of mature and compact myelin. Human or mouse glial restricted progenitors (GRPs) were transplanted into rag2 -/ - shiverer mouse neonates and followed for over one year. Mouse GRPs produced mature myelin as detected with multi-parametric MRI, but showed limited migration without extended animal lifespan. In sharp contrast, human GRPs migrated extensively and significantly increased animal survival, but production of mature myelin did not occur until 46weeks post-grafting. We conclude that human GRPs can extend the survival of transplanted shiverer mice prior to production of mature myelin, while mouse GRPs fail to extend animal survival despite the early presence of mature myelin. This paradox suggests that transplanted GRPs provide therapeutic benefits through biological processes other than the formation of mature myelin capable to foster rapid nerve conduction, challenging the current dogma of the primary role of myelination in regaining function of the central nervous system. Copyright © 2017 Elsevier Inc. All rights reserved.

Use of “MGE Enhancers” for Labeling and Selection of Embryonic Stem Cell-Derived Medial Ganglionic Eminence (MGE) Progenitors and Neurons

PubMed Central

Chen, Ying-Jiun J.; Vogt, Daniel; Wang, Yanling; Visel, Axel; Silberberg, Shanni N.; Nicholas, Cory R.; Danjo, Teruko; Pollack, Joshua L.; Pennacchio, Len A.; Anderson, Stewart; Sasai, Yoshiki; Baraban, Scott C.; Kriegstein, Arnold R.; Alvarez-Buylla, Arturo; Rubenstein, John L. R.

2013-01-01

The medial ganglionic eminence (MGE) is an embryonic forebrain structure that generates the majority of cortical interneurons. MGE transplantation into specific regions of the postnatal central nervous system modifies circuit function and improves deficits in mouse models of epilepsy, Parkinson's disease, pain, and phencyclidine-induced cognitive deficits. Herein, we describe approaches to generate MGE-like progenitor cells from mouse embryonic stem (ES) cells. Using a modified embryoid body method, we provided gene expression evidence that mouse ES-derived Lhx6+ cells closely resemble immature interneurons generated from authentic MGE-derived Lhx6+ cells. We hypothesized that enhancers that are active in the mouse MGE would be useful tools in detecting when ES cells differentiate into MGE cells. Here we demonstrate the utility of enhancer elements [422 (DlxI12b), Lhx6, 692, 1056, and 1538] as tools to mark MGE-like cells in ES cell differentiation experiments. We found that enhancers DlxI12b, 692, and 1538 are active in Lhx6-GFP+ cells, while enhancer 1056 is active in Olig2+ cells. These data demonstrate unique techniques to follow and purify MGE-like derivatives from ES cells, including GABAergic cortical interneurons and oligodendrocytes, for use in stem cell-based therapeutic assays and treatments. PMID:23658702

A perspective on high-frequency ultrasound for medical applications

NASA Astrophysics Data System (ADS)

Mamou, Jonathan; Aristizába, Orlando; Silverman, Ronald H.; Ketterling, Jeffrey A.

2010-01-01

High-frequency ultrasound (HFU, >15 MHz) is a rapidly developing field. HFU is currently used and investigated for ophthalmologic, dermatologic, intravascular, and small-animal imaging. HFU offers a non-invasive means to investigate tissue at the microscopic level with resolutions often better than 100 μm. However, fine resolution is only obtained over the limited depth-of-field (˜1 mm) of single-element spherically-focused transducers typically used for HFU applications. Another limitation is penetration depth because most biological tissues have large attenuation at high frequencies. In this study, two 5-element annular arrays with center frequencies of 17 and 34 MHz were fabricated and methods were developed to obtain images with increased penetration depth and depth-of-field. These methods were used in ophthalmologic and small-animal imaging studies. Improved blood sensitivity was obtained when a phantom mimicking a vitreous hemorrhage was imaged. Central-nervous systems of 12.5-day-old mouse embryos were imaged in utero and in three dimensions for the first time.

Evolution of Osteocrin as an activity-regulated factor in the primate brain

PubMed Central

Ataman, Bulent; Boulting, Gabriella L.; Harmin, David A.; Yang, Marty G.; Baker-Salisbury, Mollie; Yap, Ee-Lynn; Malik, Athar N.; Mei, Kevin; Rubin, Alex A.; Spiegel, Ivo; Durresi, Ershela; Sharma, Nikhil; Hu, Linda S.; Pletikos, Mihovil; Griffith, Eric C.; Partlow, Jennifer N.; Stevens, Christine R.; Adli, Mazhar; Chahrour, Maria; Sestan, Nenad; Walsh, Christopher A.; Berezovskii, Vladimir K.; Livingstone, Margaret S.; Greenberg, Michael E.

2017-01-01

Sensory stimuli drive the maturation and function of the mammalian nervous system in part through the activation of gene expression networks that regulate synapse development and plasticity. These networks have primarily been studied in mice, and it is not known whether there are species- or clade-specific activity-regulated genes that control features of brain development and function. Here we use transcriptional profiling of human fetal brain cultures to identify an activity-dependent secreted factor, Osteocrin (OSTN), that is induced by membrane depolarization of human but not mouse neurons. We find that OSTN has been repurposed in primates through the evolutionary acquisition of DNA regulatory elements that bind the activity-regulated transcription factor MEF2. In addition, we demonstrate that OSTN is expressed in primate neocortex and restricts activity-dependent dendritic growth in human neurons. These findings suggest that, in response to sensory input, OSTN regulates features of neuronal structure and function that are unique to primates. PMID:27830782

Brain metastases of breast cancer.

PubMed

Palmieri, Diane; Smith, Quentin R; Lockman, Paul R; Bronder, Julie; Gril, Brunilde; Chambers, Ann F; Weil, Robert J; Steeg, Patricia S

Central nervous system or brain metastases traditionally occur in 10-16% of metastatic breast cancer patients and are associated with a dismal prognosis. The development of brain metastases has been associated with young age, and tumors that are estrogen receptor negative, Her-2+ or of the basal phenotype. Treatment typically includes whole brain irradiation, or either stereotactic radiosurgery or surgery with whole brain radiation, resulting in an approximately 20% one year survival. The blood-brain barrier is a formidable obstacle to the delivery of chemotherapeutics to the brain. Mouse experimental metastasis model systems have been developed for brain metastasis using selected sublines of human MDA-MB-231 breast carcinoma cells. Using micron sized iron particles and MRI imaging, the fate of MDA-MB-231BR cells has been mapped: Approximately 2% of injected cells form larger macroscopic metastases, while 5% of cells remain as dormant cells in the brain. New therapies with permeability for the blood-brain barrier are needed to counteract both types of tumor cells.

The Trace Amine 1 receptor knockout mouse: an animal model with relevance to schizophrenia.

PubMed

Wolinsky, T D; Swanson, C J; Smith, K E; Zhong, H; Borowsky, B; Seeman, P; Branchek, T; Gerald, C P

2007-10-01

Trace amines have been implicated in a number of neuropsychiatric disorders including depression and schizophrenia. Although long known to modulate neurotransmission indirectly through the release of catecholamines, the identification of the Trace Amine 1 receptor (TA1) offers a mechanism by which trace amines can influence synaptic activity directly. TA1 binds and is activated by trace amines such as beta-phenylethylamine and tyramine. Our pharmacological characterization of mouse TA1 showed that, as in rat and primate, amphetamine is an agonist at this receptor but with surprisingly high potency. Without selective ligands for TA1 that do not also possess catecholamine-releasing properties, however, it has not been possible to study its physiological role in the central nervous system. To that end, a line of mice lacking the TA1 receptor was generated to characterize its contribution to the regulation of behavior. Compared with wild-type littermates, TA1 knockout (KO) mice displayed a deficit in prepulse inhibition. Knockout animals, in which the TA1-agonist influence of amphetamine was absent, showed enhanced sensitivity to the psychomotor-stimulating effect of this drug, which was temporally correlated with significantly larger increases in the release of both dopamine and norepinephrine in the dorsal striatum and associated with a 262% increase in the proportion of striatal high-affinity D2 receptors. TA1 therefore appears to play a modulatory role in catecholaminergic function and represents a potentially novel mechanism for the treatment of neuropsychiatric disorders. Furthermore, the TA1 KO mouse may provide a useful model for the development of treatments for some positive symptoms of schizophrenia.

Persistent hyperplastic primary vitreous in transgenic mice expressing IE180 of the pseudorabies virus.

PubMed

Taharaguchi, Satoshi; Yoshida, Kazuhiko; Tomioka, Yukiko; Yoshino, Saori; Uede, Toshimitsu; Ono, Etsuro

2005-05-01

Pseudorabies virus (PRV), a representative member of the alpha-herpesvirus family, causes nervous symptoms and ocular lesions, such as keratoconjunctivitis and retinal degeneration in piglets. The immediate-early protein IE180 of the PRV is known to be essential, not only in viral gene expression, but also in the cellular gene expression in host cells. The purpose of this study was to examine the effect of IE180 on the development of the mouse eye, by using transgenic technology. Transgenic mice expressing IE180 were generated and their eyes analyzed by histology, immunocytochemistry, and the bromodeoxyuridine cell proliferation assay. A fibrovascular retrolental tissue analogous to persistent hyperplastic primary vitreous (PHPV) in humans was observed in a transgenic mouse line expressing IE180. The gross anatomy of the eye showed white pupils. Analysis of hematoxylin and eosin-stained sections revealed that the retrolental tissue adhered to the neuroretina, the inner nuclear and ganglion cell layers were disorganized, and rosettelike arrangements of dysplastic photoreceptor cells were present. Bromodeoxyuridine-positive cells were detected in the retrolental tissues of postnatal day (P)1, P7, and P14 mice. The retrolental mass in the P7 transgenic mouse was composed of melanocytes and endothelial cells, which were detected by a cocktail of antibodies against endoglin, CD31, and VEGF receptor-2. The observation that the eye disease in transgenic mice is similar to that in PHPV in humans raises the possibility that expression of the immediate-early gene of alpha-herpesviruses may contribute to PHPV.

Neurobehavioral Mutants Identified in an ENU Mutagenesis Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cook, Melloni N.; Dunning, Jonathan P; Wiley, Ronald G

2007-01-01

We report on a behavioral screening test battery that successfully identified several neurobehavioral mutants among a large-scale ENU-mutagenized mouse population. Large numbers of ENU mutagenized mice were screened for abnormalities in central nervous system function based on abnormal performance in a series of behavior tasks. We developed and employed a high-throughput screen of behavioral tasks to detect behavioral outliers. Twelve mutant pedigrees, representing a broad range of behavioral phenotypes, have been identified. Specifically, we have identified two open field mutants (one displaying hyper-locomotion, the other hypo-locomotion), four tail suspension mutants (all displaying increased immobility), one nociception mutant (displaying abnormal responsivenessmore » to thermal pain), two prepulse inhibition mutants (displaying poor inhibition of the startle response), one anxiety-related mutant (displaying decreased anxiety in the light/dark test), and one learning and memory mutant (displaying reduced response to the conditioned stimulus) These findings highlight the utility of a set of behavioral tasks used in a high throughput screen to identify neurobehavioral mutants. Further analysis (i.e., behavioral and genetic mapping studies) of mutants is in progress with the ultimate goal of identification of novel genes and mouse models relevant to human disorders as well as the identification of novel therapeutic targets.« less

An optimized method for neurotransmitters and their metabolites analysis in mouse hypothalamus by high performance liquid chromatography-Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry.

PubMed

Yang, Zong-Lin; Li, Hui; Wang, Bing; Liu, Shu-Ying

2016-02-15

Neurotransmitters (NTs) and their metabolites are known to play an essential role in maintaining various physiological functions in nervous system. However, there are many difficulties in the detection of NTs together with their metabolites in biological samples. A new method for NTs and their metabolites detection by high performance liquid chromatography coupled with Q Exactive hybrid quadruple-orbitrap high-resolution accurate mass spectrometry (HPLC-HRMS) was established in this paper. This method was a great development of the applying of Q Exactive MS in the quantitative analysis. This method enabled a rapid quantification of ten compounds within 18min. Good linearity was obtained with a correlation coefficient above 0.99. The concentration range of the limit of detection (LOD) and the limit of quantitation (LOQ) level were 0.0008-0.05nmol/mL and 0.002-25.0nmol/mL respectively. Precisions (relative standard deviation, RSD) of this method were at 0.36-12.70%. Recovery ranges were between 81.83% and 118.04%. Concentrations of these compounds in mouse hypothalamus were detected by Q Exactive LC-MS technology with this method. Copyright © 2016 Elsevier B.V. All rights reserved.

Expansion and differentiation of neural progenitors derived from the human adult enteric nervous system.

PubMed

Metzger, Marco; Bareiss, Petra M; Danker, Timm; Wagner, Silvia; Hennenlotter, Joerg; Guenther, Elke; Obermayr, Florian; Stenzl, Arnulf; Koenigsrainer, Alfred; Skutella, Thomas; Just, Lothar

2009-12-01

Neural stem and progenitor cells from the enteric nervous system have been proposed for use in cell-based therapies against specific neurogastrointestinal disorders. Recently, enteric neural progenitors were generated from human neonatal and early postnatal (until 5 years after birth) gastrointestinal tract tissues. We investigated the proliferation and differentiation of enteric nervous system progenitors isolated from human adult gastrointestinal tract. Human enteric spheroids were generated from adult small and large intestine tissues and then expanded and differentiated, depending on the applied cell culture conditions. For implantation studies, spheres were grafted into fetal slice cultures and embryonic aganglionic hindgut explants from mice. Differentiating enteric neural progenitors were characterized by 5-bromo-2-deoxyuridine labeling, in situ hybridization, immunocytochemistry, quantitative real-time polymerase chain reaction, and electrophysiological studies. The yield of human neurosphere-like bodies was increased by culture in conditional medium derived from fetal mouse enteric progenitors. We were able to generate proliferating enterospheres from adult human small or large intestine tissues; these enterospheres could be subcultured and maintained for several weeks in vitro. Spheroid-derived cells could be differentiated into a variety of neuronal subtypes and glial cells with characteristics of the enteric nervous system. Experiments involving implantation into organotypic intestinal cultures showed the differentiation capacity of neural progenitors in a 3-dimensional environment. It is feasible to isolate and expand enteric progenitor cells from human adult tissue. These findings offer new strategies for enteric stem cell research and future cell-based therapies.

Evolution of eumetazoan nervous systems: insights from cnidarians.

PubMed

Kelava, Iva; Rentzsch, Fabian; Technau, Ulrich

2015-12-19

Cnidarians, the sister group to bilaterians, have a simple diffuse nervous system. This morphological simplicity and their phylogenetic position make them a crucial group in the study of the evolution of the nervous system. The development of their nervous systems is of particular interest, as by uncovering the genetic programme that underlies it, and comparing it with the bilaterian developmental programme, it is possible to make assumptions about the genes and processes involved in the development of ancestral nervous systems. Recent advances in sequencing methods, genetic interference techniques and transgenic technology have enabled us to get a first glimpse into the molecular network underlying the development of a cnidarian nervous system-in particular the nervous system of the anthozoan Nematostella vectensis. It appears that much of the genetic network of the nervous system development is partly conserved between cnidarians and bilaterians, with Wnt and bone morphogenetic protein (BMP) signalling, and Sox genes playing a crucial part in the differentiation of neurons. However, cnidarians possess some specific characteristics, and further studies are necessary to elucidate the full regulatory network. The work on cnidarian neurogenesis further accentuates the need to study non-model organisms in order to gain insights into processes that shaped present-day lineages during the course of evolution. © 2015 The Authors.

Sox2 is required for embryonic development of the ventral telencephalon through the activation of the ventral determinants Nkx2.1 and Shh.

PubMed

Ferri, Anna; Favaro, Rebecca; Beccari, Leonardo; Bertolini, Jessica; Mercurio, Sara; Nieto-Lopez, Francisco; Verzeroli, Cristina; La Regina, Federico; De Pietri Tonelli, Davide; Ottolenghi, Sergio; Bovolenta, Paola; Nicolis, Silvia K

2013-03-01

The Sox2 transcription factor is active in stem/progenitor cells throughout the developing vertebrate central nervous system. However, its conditional deletion at E12.5 in mouse causes few brain developmental problems, with the exception of the postnatal loss of the hippocampal radial glia stem cells and the dentate gyrus. We deleted Sox2 at E9.5 in the telencephalon, using a Bf1-Cre transgene. We observed embryonic brain defects that were particularly severe in the ventral, as opposed to the dorsal, telencephalon. Important tissue loss, including the medial ganglionic eminence (MGE), was detected at E12.5, causing the subsequent impairment of MGE-derived neurons. The defect was preceded by loss of expression of the essential ventral determinants Nkx2.1 and Shh, and accompanied by ventral spread of dorsal markers. This phenotype is reminiscent of that of mice mutant for the transcription factor Nkx2.1 or for the Shh receptor Smo. Nkx2.1 is known to mediate the initial activation of ventral telencephalic Shh expression. A partial rescue of the normal phenotype at E14.5 was obtained by administration of a Shh agonist. Experiments in Medaka fish indicate that expression of Nkx2.1 is regulated by Sox2 in this species also. We propose that Sox2 contributes to Nkx2.1 expression in early mouse development, thus participating in the region-specific activation of Shh, thereby mediating ventral telencephalic patterning induction.

Regulation of neural macroRNAs by the transcriptional repressor REST

PubMed Central

Johnson, Rory; Teh, Christina Hui-Leng; Jia, Hui; Vanisri, Ravi Raj; Pandey, Tridansh; Lu, Zhong-Hao; Buckley, Noel J.; Stanton, Lawrence W.; Lipovich, Leonard

2009-01-01

The essential transcriptional repressor REST (repressor element 1-silencing transcription factor) plays central roles in development and human disease by regulating a large cohort of neural genes. These have conventionally fallen into the class of known, protein-coding genes; recently, however, several noncoding microRNA genes were identified as REST targets. Given the widespread transcription of messenger RNA-like, noncoding RNAs (“macroRNAs”), some of which are functional and implicated in disease in mammalian genomes, we sought to determine whether this class of noncoding RNAs can also be regulated by REST. By applying a new, unbiased target gene annotation pipeline to computationally discovered REST binding sites, we find that 23% of mammalian REST genomic binding sites are within 10 kb of a macroRNA gene. These putative target genes were overlooked by previous studies. Focusing on a set of 18 candidate macroRNA targets from mouse, we experimentally demonstrate that two are regulated by REST in neural stem cells. Flanking protein-coding genes are, at most, weakly repressed, suggesting specific targeting of the macroRNAs by REST. Similar to the majority of known REST target genes, both of these macroRNAs are induced during nervous system development and have neurally restricted expression profiles in adult mouse. We observe a similar phenomenon in human: the DiGeorge syndrome-associated noncoding RNA, DGCR5, is repressed by REST through a proximal upstream binding site. Therefore neural macroRNAs represent an additional component of the REST regulatory network. These macroRNAs are new candidates for understanding the role of REST in neuronal development, neurodegeneration, and cancer. PMID:19050060

Regulation of neural macroRNAs by the transcriptional repressor REST.

PubMed

Johnson, Rory; Teh, Christina Hui-Leng; Jia, Hui; Vanisri, Ravi Raj; Pandey, Tridansh; Lu, Zhong-Hao; Buckley, Noel J; Stanton, Lawrence W; Lipovich, Leonard

2009-01-01

The essential transcriptional repressor REST (repressor element 1-silencing transcription factor) plays central roles in development and human disease by regulating a large cohort of neural genes. These have conventionally fallen into the class of known, protein-coding genes; recently, however, several noncoding microRNA genes were identified as REST targets. Given the widespread transcription of messenger RNA-like, noncoding RNAs ("macroRNAs"), some of which are functional and implicated in disease in mammalian genomes, we sought to determine whether this class of noncoding RNAs can also be regulated by REST. By applying a new, unbiased target gene annotation pipeline to computationally discovered REST binding sites, we find that 23% of mammalian REST genomic binding sites are within 10 kb of a macroRNA gene. These putative target genes were overlooked by previous studies. Focusing on a set of 18 candidate macroRNA targets from mouse, we experimentally demonstrate that two are regulated by REST in neural stem cells. Flanking protein-coding genes are, at most, weakly repressed, suggesting specific targeting of the macroRNAs by REST. Similar to the majority of known REST target genes, both of these macroRNAs are induced during nervous system development and have neurally restricted expression profiles in adult mouse. We observe a similar phenomenon in human: the DiGeorge syndrome-associated noncoding RNA, DGCR5, is repressed by REST through a proximal upstream binding site. Therefore neural macroRNAs represent an additional component of the REST regulatory network. These macroRNAs are new candidates for understanding the role of REST in neuronal development, neurodegeneration, and cancer.

Systemic Central Nervous System (CNS)-targeted Delivery of Neuropeptide Y (NPY) Reduces Neurodegeneration and Increases Neural Precursor Cell Proliferation in a Mouse Model of Alzheimer Disease.

PubMed

Spencer, Brian; Potkar, Rewati; Metcalf, Jeff; Thrin, Ivy; Adame, Anthony; Rockenstein, Edward; Masliah, Eliezer

2016-01-22

Neuropeptide Y (NPY) is one of the most abundant protein transmitters in the central nervous system with roles in a variety of biological functions including: food intake, cardiovascular regulation, cognition, seizure activity, circadian rhythms, and neurogenesis. Reduced NPY and NPY receptor expression is associated with numerous neurodegenerative disorders including Alzheimer disease (AD). To determine whether replacement of NPY could ameliorate some of the neurodegenerative and behavioral pathology associated with AD, we generated a lentiviral vector expressing NPY fused to a brain transport peptide (apoB) for widespread CNS delivery in an APP-transgenic (tg) mouse model of AD. The recombinant NPY-apoB effectively reversed neurodegenerative pathology and behavioral deficits although it had no effect on accumulation of Aβ. The subgranular zone of the hippocampus showed a significant increase in proliferation of neural precursor cells without further differentiation into neurons. The neuroprotective and neurogenic effects of NPY-apoB appeared to involve signaling via ERK and Akt through the NPY R1 and NPY R2 receptors. Thus, widespread CNS-targeted delivery of NPY appears to be effective at reversing the neuronal and glial pathology associated with Aβ accumulation while also increasing NPC proliferation. Overall, increased delivery of NPY to the CNS for AD might be an effective therapy especially if combined with an anti-Aβ therapeutic. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Effects of realgar on GSH synthesis in the mouse hippocampus: Involvement of system X{sub AG}{sup −}, system X{sub C}{sup −}, MRP-1 and Nrf2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yanlei

Realgar is a type of mineral drug that contains arsenic and has neurotoxicity. Glutathione (GSH), which is the main antioxidant in the central nervous system, plays a key role in antioxidant defenses and the detoxification of arsenic. However, whether realgar interferes with the synthesis of GSH in the brain and the molecular mechanisms underlying its effects are largely unknown. Here, we used mouse models of exposure to realgar to show that realgar affects the synthesis of GSH in the hippocampus, leading to ultrastructural changes in hippocampal neurons and synapses and deficiencies in cognitive abilities, and that the mechanisms that causemore » this effect may be associated with alterations in the expression of system X{sub AG}{sup −}, system X{sub C}{sup −}, multidrug resistance-associated protein 1(MRP-1), nuclear factor E2-related factor 2 (Nrf2), γ-glutamylcysteine synthetase (γ-GCS), and the levels of glutamate (Glu) and cysteine (Cys) in the extracellular fluid. These findings provide a theoretical basis for preventing the drug-induced chronic arsenic poisoning in the nervous system that is triggered by realgar. - Highlights: • Realgar can induce neurotoxicity. • Realgar can modulate GSH levels in the hippocampus. • The mechanisms rely on expression changes of system X{sub AG}{sup −}, system X{sub C}{sup −}, MRP-1, Nrf2.« less

Full Tensor Diffusion Imaging Is Not Required To Assess the White-Matter Integrity in Mouse Contusion Spinal Cord Injury

PubMed Central

Tu, Tsang-Wei; Kim, Joong H.; Wang, Jian

2010-01-01

Abstract In vivo diffusion tensor imaging (DTI) derived indices have been demonstrated to quantify accurately white-matter injury after contusion spinal cord injury (SCI) in rodents. In general, a full diffusion tensor analysis requires the acquisition of diffusion-weighted images (DWI) along at least six independent directions of diffusion-sensitizing gradients. Thus, DTI measurements of the rodent central nervous system are time consuming. In this study, diffusion indices derived using the two-direction DWI (parallel and perpendicular to axonal tracts) were compared with those obtained using six-direction DTI in a mouse model of SCI. It was hypothesized that the mouse spinal cord ventral-lateral white-matter (VLWM) tracts, T8–T10 in this study, aligned with the main magnet axis (z) allowing the apparent diffusion coefficient parallel and perpendicular to the axis of the spine to be derived with diffusion-weighting gradients in the z and y axes of the magnet coordinate respectively. Compared with six-direction full tensor DTI, two-direction DWI provided comparable diffusion indices in mouse spinal cords. The measured extent of spared white matter after injury, estimated by anisotropy indices, using both six-direction DTI and two-direction DWI were in close agreement and correlated well with histological staining and behavioral assessment. The results suggest that the two-direction DWI derived indices may be used, with significantly reduced imaging time, to estimate accurately spared white matter in mouse SCI. PMID:19715399

Naked mole-rat cortical neurons are resistant to acid-induced cell death.

PubMed

Husson, Zoé; Smith, Ewan St John

2018-05-09

Regulation of brain pH is a critical homeostatic process and changes in brain pH modulate various ion channels and receptors and thus neuronal excitability. Tissue acidosis, resulting from hypoxia or hypercapnia, can activate various proteins and ion channels, among which acid-sensing ion channels (ASICs) a family of primarily Na + permeable ion channels, which alongside classical excitotoxicity causes neuronal death. Naked mole-rats (NMRs, Heterocephalus glaber) are long-lived, fossorial, eusocial rodents that display remarkable behavioral/cellular hypoxia and hypercapnia resistance. In the central nervous system, ASIC subunit expression is similar between mouse and NMR with the exception of much lower expression of ASIC4 throughout the NMR brain. However, ASIC function and neuronal sensitivity to sustained acidosis has not been examined in the NMR brain. Here, we show with whole-cell patch-clamp electrophysiology of cultured NMR and mouse cortical and hippocampal neurons that NMR neurons have smaller voltage-gated Na + channel currents and more hyperpolarized resting membrane potentials. We further demonstrate that acid-mediated currents in NMR neurons are of smaller magnitude than in mouse, and that all currents in both species are reversibly blocked by the ASIC antagonist benzamil. We further demonstrate that NMR neurons show greater resistance to acid-induced cell death than mouse neurons. In summary, NMR neurons show significant cellular resistance to acidotoxicity compared to mouse neurons, contributing factors likely to be smaller ASIC-mediated currents and reduced NaV activity.

Quantitative Analyses of Synergistic Responses between Cannabidiol and DNA-Damaging Agents on the Proliferation and Viability of Glioblastoma and Neural Progenitor Cells in Culture.

PubMed

Deng, Liting; Ng, Lindsay; Ozawa, Tatsuya; Stella, Nephi

2017-01-01

Evidence suggests that the nonpsychotropic cannabis-derived compound, cannabidiol (CBD), has antineoplastic activity in multiple types of cancers, including glioblastoma multiforme (GBM). DNA-damaging agents remain the main standard of care treatment available for patients diagnosed with GBM. Here we studied the antiproliferative and cell-killing activity of CBD alone and in combination with DNA-damaging agents (temozolomide, carmustine, or cisplatin) in several human GBM cell lines and in mouse primary GBM cells in cultures. This activity was also studied in mouse neural progenitor cells (NPCs) in culture to assess for potential central nervous system toxicity. We found that CBD induced a dose-dependent reduction of both proliferation and viability of all cells with similar potencies, suggesting no preferential activity for cancer cells. Hill plot analysis indicates an allosteric mechanism of action triggered by CBD in all cells. Cotreatment regimens combining CBD and DNA-damaging agents produced synergistic antiproliferating and cell-killing responses over a limited range of concentrations in all human GBM cell lines and mouse GBM cells as well as in mouse NPCs. Remarkably, antagonistic responses occurred at low concentrations in select human GBM cell lines and in mouse GBM cells. Our study suggests limited synergistic activity when combining CBD and DNA-damaging agents in treating GBM cells, along with little to no therapeutic window when considering NPCs. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Neuroprotection in a Novel Mouse Model of Multiple Sclerosis

PubMed Central

Lidster, Katie; Jackson, Samuel J.; Ahmed, Zubair; Munro, Peter; Coffey, Pete; Giovannoni, Gavin; Baker, Mark D.; Baker, David

2013-01-01

Multiple sclerosis is an immune-mediated, demyelinating and neurodegenerative disease that currently lacks any neuroprotective treatments. Innovative neuroprotective trial designs are required to hasten the translational process of drug development. An ideal target to monitor the efficacy of strategies aimed at treating multiple sclerosis is the visual system, which is the most accessible part of the human central nervous system. A novel C57BL/6 mouse line was generated that expressed transgenes for a myelin oligodendrocyte glycoprotein-specific T cell receptor and a retinal ganglion cell restricted-Thy1 promoter-controlled cyan fluorescent protein. This model develops spontaneous or induced optic neuritis, in the absence of paralytic disease normally associated with most rodent autoimmune models of multiple sclerosis. Demyelination and neurodegeneration could be monitored longitudinally in the living animal using electrophysiology, visual sensitivity, confocal scanning laser ophthalmoscopy and optical coherence tomography all of which are relevant to human trials. This model offers many advantages, from a 3Rs, economic and scientific perspective, over classical experimental autoimmune encephalomyelitis models that are associated with substantial suffering of animals. Optic neuritis in this model led to inflammatory damage of axons in the optic nerve and subsequent loss of retinal ganglion cells in the retina. This was inhibited by the systemic administration of a sodium channel blocker (oxcarbazepine) or intraocular treatment with siRNA targeting caspase-2. These novel approaches have relevance to the future treatment of neurodegeneration of MS, which has so far evaded treatment. PMID:24223903

Optimizing promoters for recombinant adeno-associated virus-mediated gene expression in the peripheral and central nervous system using self-complementary vectors.

PubMed

Gray, Steven J; Foti, Stacey B; Schwartz, Joel W; Bachaboina, Lavanya; Taylor-Blake, Bonnie; Coleman, Jennifer; Ehlers, Michael D; Zylka, Mark J; McCown, Thomas J; Samulski, R Jude

2011-09-01

With the increased use of small self-complementary adeno-associated viral (AAV) vectors, the design of compact promoters becomes critical for packaging and expressing larger transgenes under ubiquitous or cell-specific control. In a comparative study of commonly used 800-bp cytomegalovirus (CMV) and chicken β-actin (CBA) promoters, we report significant differences in the patterns of cell-specific gene expression in the central and peripheral nervous systems. The CMV promoter provides high initial neural expression that diminishes over time. The CBA promoter displayed mostly ubiquitous and high neural expression, but substantially lower expression in motor neurons (MNs). We report the creation of a novel hybrid form of the CBA promoter (CBh) that provides robust long-term expression in all cells observed with CMV or CBA, including MNs. To develop a short neuronal promoter to package larger transgenes into AAV vectors, we also found that a 229-bp fragment of the mouse methyl-CpG-binding protein-2 (MeCP2) promoter was able to drive neuron-specific expression within the CNS. Thus the 800-bp CBh promoter provides strong, long-term, and ubiquitous CNS expression whereas the MeCP2 promoter allows an extra 570-bp packaging capacity, with low and mostly neuronal expression within the CNS, similar to the MeCP2 transcription factor.

Upregulation of the Nr2f1-A830082K12Rik gene pair in murine neural crest cells results in a complex phenotype reminiscent of Waardenburg syndrome type 4

PubMed Central

Bergeron, Karl-F.; Nguyen, Chloé M. A.; Cardinal, Tatiana; Charrier, Baptiste; Silversides, David W.

2016-01-01

ABSTRACT Waardenburg syndrome is a neurocristopathy characterized by a combination of skin and hair depigmentation, and inner ear defects. In the type 4 form, these defects show comorbidity with Hirschsprung disease, a disorder marked by an absence of neural ganglia in the distal colon, triggering functional intestinal obstruction. Here, we report that the Spot mouse line – obtained through an insertional mutagenesis screen for genes involved in neural crest cell (NCC) development – is a model for Waardenburg syndrome type 4. We found that the Spot insertional mutation causes overexpression of an overlapping gene pair composed of the transcription-factor-encoding Nr2f1 and the antisense long non-coding RNA A830082K12Rik in NCCs through a mechanism involving relief of repression of these genes. Consistent with the previously described role of Nr2f1 in promoting gliogenesis in the central nervous system, we further found that NCC-derived progenitors of the enteric nervous system fail to fully colonize Spot embryonic guts owing to their premature differentiation in glial cells. Taken together, our data thus identify silencer elements of the Nr2f1-A830082K12Rik gene pair as new candidate loci for Waardenburg syndrome type 4. PMID:27585883

Upregulation of the Nr2f1-A830082K12Rik gene pair in murine neural crest cells results in a complex phenotype reminiscent of Waardenburg syndrome type 4.

PubMed

Bergeron, Karl-F; Nguyen, Chloé M A; Cardinal, Tatiana; Charrier, Baptiste; Silversides, David W; Pilon, Nicolas

2016-11-01

Waardenburg syndrome is a neurocristopathy characterized by a combination of skin and hair depigmentation, and inner ear defects. In the type 4 form, these defects show comorbidity with Hirschsprung disease, a disorder marked by an absence of neural ganglia in the distal colon, triggering functional intestinal obstruction. Here, we report that the Spot mouse line - obtained through an insertional mutagenesis screen for genes involved in neural crest cell (NCC) development - is a model for Waardenburg syndrome type 4. We found that the Spot insertional mutation causes overexpression of an overlapping gene pair composed of the transcription-factor-encoding Nr2f1 and the antisense long non-coding RNA A830082K12Rik in NCCs through a mechanism involving relief of repression of these genes. Consistent with the previously described role of Nr2f1 in promoting gliogenesis in the central nervous system, we further found that NCC-derived progenitors of the enteric nervous system fail to fully colonize Spot embryonic guts owing to their premature differentiation in glial cells. Taken together, our data thus identify silencer elements of the Nr2f1-A830082K12Rik gene pair as new candidate loci for Waardenburg syndrome type 4. © 2016. Published by The Company of Biologists Ltd.

Enhanced taurine release in cell-damaging conditions in the developing and ageing mouse hippocampus.

PubMed

Saransaari, P; Oja, S S

1997-08-01

Taurine has been shown to be essential for neuronal development and survival in the central nervous system. The release of preloaded [3H]taurine was studied in hippocampal slices from seven-day-, three-month- and 18-22-month-old mice in cell-damaging conditions. The slices were superfused in hypoxic, hypoglycemic and ischemic conditions and exposed to free radicals and oxidative stress. The release of taurine was greatly enhanced in the above conditions in all age groups, except in oxidative stress. The release was large in ischemia, particularly in the hippocampus of aged mice. Potassium stimulation was still able to release taurine in cell-damaging conditions in immature mice, whereas in adult and aged animals the release was so substantial that this additional stimulus failed to work. Taurine release was partially Ca2+-dependent in all cases. The massive release of the inhibitory amino acid taurine in ischemic conditions could act neuroprotectively, counteracting in several ways the effects of simultaneous release of excitatory amino acids. This protection could be of great importance in developing brain tissue, while also having an effect in aged brains.

Chronic estrogen deficiency leads to molecular aberrations related to neurodegenerative changes in follitropin receptor knockout female mice.

PubMed

Tam, J; Danilovich, N; Nilsson, K; Sairam, M R; Maysinger, D

2002-01-01

The follitropin receptor knockout (FORKO) mouse undergoes ovarian failure, thereby providing an animal model to investigate the consequences of the depletion of circulating estrogen in females. The estrogen deficiency causes marked defects in the female reproductive system, obesity, and skeletal abnormalities. In light of estrogen's known pleiotropic effects in the nervous system, our study examined the effects of genetically induced estrogen-testosterone imbalance on this system in female FORKO mice. Circulating concentrations of 17-beta-estradiol (E2) in FORKO mice are significantly decreased (FORKO -/-: 1.13+/-0.34 pg/ml; wild-type +/+: 17.6+/-3.5 pg/ml, P<0.0001, n=32-41); in contrast, testosterone levels are increased (-/-: 37.7+/-2.3 pg/ml; wild-type +/+: 3.9+/-1.7 pg/ml, P<0.005, n=25-33). The focus was on the activities of key enzymes in the central cholinergic and peripheral nervous systems, on dorsal root ganglia (DRGs) capacity for neurite outgrowth, and on the phosphorylation state of structural neurofilament (NF) proteins. Choline acetyltransferase activity was decreased in several central cholinergic structures (striatum 50+/-3%, hippocampus 24+/-2%, cortex 12+/-3%) and in DRGs (11+/-6%). Moreover, we observed aberrations in the enzymatic activities of mitogen-activated protein kinases (extracellular-regulated kinase and c-Jun N-terminal kinase) in the hippocampus, DRGs, and sciatic nerves. Hippocampal and sensory ganglia samples from FORKO mice contained hyper-phosphorylated NFs. Finally, explanted ganglia of FORKO mice displayed decreased neurite outgrowth (20-50%) under non-treated conditions and when treated with E2 (10 nM). Our results demonstrate that genetic depletion of circulating estrogen leads to biochemical and morphological changes in central and peripheral neurons, and underlie the importance of estrogen in the normal development and functioning of the nervous system. In particular, the findings suggest that an early and persisting absence of the steroid leads to neurodegenerative changes and identify several key enzymes that may contribute to the process. This model provides a system to explore the consequences of circulating estrogen deprivation and other hormonal imbalances in the nervous system.

Nuclear factor I-A represses expression of the cell adhesion molecule L1

PubMed Central

2009-01-01

Background The neural cell adhesion molecule L1 plays a crucial role in development and plasticity of the nervous system. Neural cells thus require precise control of L1 expression. Results We identified a full binding site for nuclear factor I (NFI) transcription factors in the regulatory region of the mouse L1 gene. Electrophoretic mobility shift assay (EMSA) showed binding of nuclear factor I-A (NFI-A) to this site. Moreover, for a brain-specific isoform of NFI-A (NFI-A bs), we confirmed the interaction in vivo using chromatin immunoprecipitation (ChIP). Reporter gene assays showed that in neuroblastoma cells, overexpression of NFI-A bs repressed L1 expression threefold. Conclusion Our findings suggest that NFI-A, in particular its brain-specific isoform, represses L1 gene expression, and might act as a second silencer of L1 in addition to the neural restrictive silencer factor (NRSF). PMID:20003413

Survival of adult neurons lacking cholesterol synthesis in vivo.

PubMed

Fünfschilling, Ursula; Saher, Gesine; Xiao, Le; Möbius, Wiebke; Nave, Klaus-Armin

2007-01-02

Cholesterol, an essential component of all mammalian plasma membranes, is highly enriched in the brain. Both during development and in the adult, brain cholesterol is derived from local cholesterol synthesis and not taken up from the circulation. However, the contribution of neurons and glial cells to total brain cholesterol metabolism is unknown. Using conditional gene inactivation in the mouse, we disrupted the squalene synthase gene (fdft1), which is critical for cholesterol synthesis, in cerebellar granule cells and some precerebellar nuclei. Mutant mice showed no histological signs of neuronal degeneration, displayed ultrastructurally normal synapses, and exhibited normal motor coordination. This revealed that these adult neurons do not require cell-autonomous cholesterol synthesis for survival or function. We conclude that at least some adult neurons no longer require endogenous cholesterol synthesis and can fully meet their cholesterol needs by uptake from their surrounding. Glia are a likely source of cholesterol in the central nervous system.

Non-equivalent antigen presenting capabilities of dendritic cells and macrophages in generating brain-infiltrating CD8 + T cell responses.

PubMed

Malo, Courtney S; Huggins, Matthew A; Goddery, Emma N; Tolcher, Heather M A; Renner, Danielle N; Jin, Fang; Hansen, Michael J; Pease, Larry R; Pavelko, Kevin D; Johnson, Aaron J

2018-02-12

The contribution of antigen-presenting cell (APC) types in generating CD8 + T cell responses in the central nervous system (CNS) is not fully defined, limiting the development of vaccines and understanding of immune-mediated neuropathology. Here, we generate a transgenic mouse that enables cell-specific deletion of the H-2Kb MHC class I molecule. By deleting H-2K b on dendritic cells and macrophages, we compare the effect of each APC in three distinct models of neuroinflammation: picornavirus infection, experimental cerebral malaria, and a syngeneic glioma. Dendritic cells and macrophages both activate CD8 + T cell responses in response to these CNS immunological challenges. However, the extent to which each of these APCs contributes to CD8 + T cell priming varies. These findings reveal distinct functions for dendritic cells and macrophages in generating CD8 + T cell responses to neurological disease.

S-adenosylmethionine levels regulate the Schwann cell DNA methylome

PubMed Central

Varela-Rey, Marta; Iruarrizaga-Lejarreta, Marta; Lozano, Juan José; Aransay, Ana María; Fernandez, Agustín F.; Lavin, José Luis; Mósen-Ansorena, David; Berdasco, María; Turmaine, Marc; Luka, Zigmund; Wagner, Conrad; Lu, Shelly C.; Esteller, Manel; Mirsky, Rhona; Jessen, Kristján R.; Fraga, Mario F.; Martínez-Chantar, María L.; Mato, José M.; Woodhoo, Ashwin

2014-01-01

SUMMARY Axonal myelination is essential for rapid saltatory impulse conduction in the nervous system, and malformation or destruction of myelin sheaths leads to motor and sensory disabilities. DNA methylation is an essential epigenetic modification during mammalian development, yet its role in myelination remains obscure. Here, using high-resolution methylome maps, we show that DNA methylation could play a key gene regulatory role in peripheral nerve myelination and that S-adenosylmethionine (SAMe), the principal methyl donor in cytosine methylation, regulates the methylome dynamics during this process. Our studies also point to a possible role of SAMe in establishing the aberrant DNA methylation patterns in a mouse model of diabetic neuropathy, implicating SAMe in the pathogenesis of this disease. These critical observations establish a link between SAMe and DNA methylation status in a defined biological system, and provides a novel mechanism that could direct methylation changes during cellular differentiation and in diverse pathological situations. PMID:24607226

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manglik, Aashish; Kruse, Andrew C.; Kobilka, Tong Sun

Opium is one of the world's oldest drugs, and its derivatives morphine and codeine are among the most used clinical drugs to relieve severe pain. These prototypical opioids produce analgesia as well as many undesirable side effects (sedation, apnoea and dependence) by binding to and activating the G-protein-coupled {mu}-opioid receptor ({mu}-OR) in the central nervous system. Here we describe the 2.8 {angstrom} crystal structure of the mouse {mu}-OR in complex with an irreversible morphinan antagonist. Compared to the buried binding pocket observed in most G-protein-coupled receptors published so far, the morphinan ligand binds deeply within a large solvent-exposed pocket. Ofmore » particular interest, the {mu}-OR crystallizes as a two-fold symmetrical dimer through a four-helix bundle motif formed by transmembrane segments 5 and 6. These high-resolution insights into opioid receptor structure will enable the application of structure-based approaches to develop better drugs for the management of pain and addiction.« less

What have we learned about GPER function in physiology and disease from knockout mice?

PubMed Central

Prossnitz, Eric R.; Hathaway, Helen J.

2015-01-01

Estrogens, predominantly 17β-estradiol, exert diverse effects throughout the body in both normal and patho-physiology, during development and in reproductive, metabolic, endocrine, cardiovascular, nervous, musculoskeletal and immune systems. Estrogen and its receptors also play important roles in carcinogenesis and therapy, particularly for breast cancer. In addition to the classical nuclear estrogen receptors (ERα and ERβ) that traditionally mediate predominantly genomic signaling, the G protein-coupled estrogen receptor GPER has become recognized as a critical mediator of rapid signaling in response to estrogen. Mouse models, and in particular knockout (KO) mice, represent an important approach to understand the functions of receptors in normal physiology and disease. Whereas ERα KO mice display multiple significant defects in reproduction and mammary gland development, ERβ KO phenotypes are more limited, and GPER KO exhibit no reproductive deficits. However, the study of GPER KO mice over the last six years has revealed that GPER deficiency results in multiple physiological alterations including obesity, cardiovascular dysfunction, insulin resistance and glucose intolerance. In addition, the lack of estrogen-mediated effects in numerous tissues of GPER KO mice, studied in vivo or ex vivo, including those of the cardiovascular, endocrine, nervous and immune systems, reveals GPER as a genuine mediator of estrogen action. Importantly, GPER KO mice have also revealed roles for GPER in breast carcinogenesis and metastasis. In combination with the supporting effects of GPER-selective ligands and GPER knockdown approaches, GPER KO mice demonstrate the therapeutic potential of targeting GPER activity in diseases as diverse as obesity, diabetes, multiple sclerosis, hypertension, atherosclerosis, myocardial infarction, stroke and cancer. PMID:26189910

Neuron-specific (pro)renin receptor knockout prevents the development of salt-sensitive hypertension

PubMed Central

Li, Wencheng; Peng, Hua; Mehaffey, Eamonn P.; Kimball, Christie D.; Grobe, Justin L.; van Gool, Jeanette M.G.; Sullivan, Michelle N.; Earley, Scott; Danser, A.H. Jan; Ichihara, Atsuhiro; Feng, Yumei

2013-01-01

The (pro)renin receptor, which binds both renin and prorenin, is a newly discovered component of the renin angiotensin system that is highly expressed in the central nervous system. The significance of brain PRRs in mediating local angiotensin II formation and regulating blood pressure remains unclear. The current study was performed to test the hypothesis that PRR-mediated, non-proteolytic activation of prorenin is the main source of angiotensin II in the brain. Thus, PRR knockout in the brain is expected to prevent angiotensin II formation and development of deoxycorticosterone acetate salt induced hypertension. A neuron-specific PRR (ATP6AP2) knockout mouse model was generated using the Cre-LoxP system. Physiological parameters were recorded by telemetry. (Pro)renin receptor expression, detected by immunostaining and RT-PCR, was significantly decreased in the brains of knockout compared with wide-type mice. Intracerebroventricular infusion of mouse prorenin increased blood pressure and angiotensin II formation in wild type mice. This hypertensive response was abolished in (pro)renin receptor knockout mice in association with a reduction in angiotensin II levels. Deoxycorticosterone acetate salt increased (pro)renin receptor expression and angiotensin II formation in the brains of wild-type mice, an effect that was attenuated in (pro)renin receptor knockout mice. (Pro)renin receptor knockout in neurons prevented the development of Deoxycorticosterone acetate salt-induced hypertension as well as activation of cardiac and vasomotor sympathetic tone. In conclusion, non-proteolytic activation of prorenin through binding to the PRR mediates angiotensin II formation in the brain. Neuron-specific PRR knockout prevents the development of deoxycorticosterone acetate salt-induced hypertension, possibly through diminished angiotensin II formation. PMID:24246383

The mouse Gtl2 gene is differentially expressed during embryonic development, encodes multiple alternatively spliced transcripts, and may act as an RNA.

PubMed

Schuster-Gossler, K; Bilinski, P; Sado, T; Ferguson-Smith, A; Gossler, A

1998-06-01

We have isolated a novel mouse gene (Gtl2) from the site of a gene trap integration (Gtl2lacZ) that gave rise to developmentally regulated lacZ expression, and a dominant parental-origin-dependent phenotype. Heterozygous Gtl2lacZ mice that inherited the transgene from the father showed a proportionate dwarfism phenotype, whereas the penetrance and expressivity of the phenotype was strongly reduced in Gtl2lacZ mice that inherited the transgene from the mother. Gtl2 expression is highly similar to the beta-galactosidase staining pattern, and is down-regulated but not abolished in mice carrying the Gtl2lacZ insertion. In early postimplantation embryos, Gtl2 is expressed in the visceral yolk sac and embryonic ectoderm. During subsequent development and organogenesis, Gtl2 transcripts are abundant in the paraxial mesoderm closely correlated with myogenic differentiation, in parts of the central nervous system, and in the epithelial ducts of developing excretory organs. The Gtl2 gene gives rise to various differentially spliced transcripts, which contain multiple small open reading frames (ORF). However, none of the ATG codons of these ORFs is in the context of a strong Kozak consensus sequence for initiation of translation, suggesting that Gtl2 might function as an RNA. Nuclear Gtl2 RNA was detected in a temporally and spatially regulated manner, and partially processed Gtl2 transcripts were readily detected in Northern blot hybridizations of polyadenylated RNA, suggesting that primary Gtl2 transcripts are differently processed in various cell types during development. Gtl2 transcript levels are present in parthenogenic embryos but may be reduced, consistent with the pattern of inheritance of the Gtl2lacZ phenotype.

Serotonin Receptor 6 Mediates Defective Brain Development in Monoamine Oxidase A-deficient Mouse Embryos

PubMed Central

Wang, Chi Chiu; Man, Gene Chi Wai; Chu, Ching Yan; Borchert, Astrid; Ugun-Klusek, Aslihan; Billett, E. Ellen; Kühn, Hartmut; Ufer, Christoph

2014-01-01

Monoamine oxidases A and B (MAO-A and MAO-B) are enzymes of the outer mitochondrial membrane that metabolize biogenic amines. In the adult central nervous system, MAOs have important functions for neurotransmitter homeostasis. Expression of MAO isoforms has been detected in the developing embryo. However, suppression of MAO-B does not induce developmental alterations. In contrast, targeted inhibition and knockdown of MAO-A expression (E7.5–E10.5) caused structural abnormalities in the brain. Here we explored the molecular mechanisms underlying defective brain development induced by MAO-A knockdown during in vitro embryogenesis. The developmental alterations were paralleled by diminished apoptotic activity in the affected neuronal structures. Moreover, dysfunctional MAO-A expression led to elevated levels of embryonic serotonin (5-hydroxytryptamine (5-HT)), and we found that knockdown of serotonin receptor-6 (5-Htr6) expression or pharmacologic inhibition of 5-Htr6 activity rescued the MAO-A knockdown phenotype and restored apoptotic activity in the developing brain. Our data suggest that excessive 5-Htr6 activation reduces activation of caspase-3 and -9 of the intrinsic apoptotic pathway and enhances expression of antiapoptotic proteins Bcl-2 and Bcl-XL. Moreover, we found that elevated 5-HT levels in MAO-A knockdown embryos coincided with an enhanced activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and a reduction of proliferating cell numbers. In summary, our findings suggest that excessive 5-HT in MAO-A-deficient mouse embryos triggers cellular signaling cascades via 5-Htr6, which suppresses developmental apoptosis in the brain and thus induces developmental retardations. PMID:24497636

Acid-sensing ion channels in mouse olfactory bulb M/T neurons

PubMed Central

Li, Ming-Hua; Liu, Selina Qiuying; Inoue, Koichi; Lan, Jinquan; Simon, Roger P.

2014-01-01

The olfactory bulb contains the first synaptic relay in the olfactory pathway, the sensory system in which odorants are detected enabling these chemical stimuli to be transformed into electrical signals and, ultimately, the perception of odor. Acid-sensing ion channels (ASICs), a family of proton-gated cation channels, are widely expressed in neurons of the central nervous system. However, no direct electrophysiological and pharmacological characterizations of ASICs in olfactory bulb neurons have been described. Using a combination of whole-cell patch-clamp recordings and biochemical and molecular biological analyses, we demonstrated that functional ASICs exist in mouse olfactory bulb mitral/tufted (M/T) neurons and mainly consist of homomeric ASIC1a and heteromeric ASIC1a/2a channels. ASIC activation depolarized cultured M/T neurons and increased their intracellular calcium concentration. Thus, ASIC activation may play an important role in normal olfactory function. PMID:24821964

Effects of intracerebroventricular injections of free fatty acids, lysophospholipids, or platelet activating factor in a mouse model of orofacial pain.

PubMed

Vahidy, Wajiha H; Ong, Wei-Yi; Farooqui, Akhlaq A; Yeo, Jin-Fei

2006-10-01

The present study was carried out to determine the effects of central nervous free fatty acids, lysophospholipids, or platelet activating factor (PAF), in a mouse facial carrageenan injection model of orofacial pain. Mice that received intracerebroventricular (I.C.V.) injection of arachidonic acid or oleic acid showed significantly reduced allodynia and behavioral responses to von Frey hair stimulation of a carrageenan-injected area of the face, at 8 h post-injection, compared to controls that received I.C.V. injection of vehicle. In contrast to free fatty acids, increased responses were observed in mice at 72 h after I.C.V. lysophosphatidic acid or lysophosphatidylcholine injection, and at 8 and 24 h after PAF injection, compared vehicle injected controls. Information regarding pro-nociceptive effect of specific brain lipids may be a useful basis for further studies to explore mechanism.

Cell of Origin and Cancer Stem Cells in Tumor Suppressor Mouse Models of Glioblastoma.

PubMed

Alcantara Llaguno, Sheila R; Xie, Xuanhua; Parada, Luis F

2016-01-01

The cellular origins and the mechanisms of progression, maintenance of tumorigenicity, and therapeutic resistance are central questions in the glioblastoma multiforme (GBM) field. Using tumor suppressor mouse models, our group recently reported two independent populations of adult GBM-initiating central nervous system progenitors. We found different functional and molecular subtypes depending on the tumor-initiating cell lineage, indicating that the cell of origin is a driver of GBM subtype diversity. Using an in vivo model, we also showed that GBM cancer stem cells (CSCs) or glioma stem cells (GSCs) contribute to resistance to chemotherapeutic agents and that genetic ablation of GSCs leads to a delay in tumor progression. These studies are consistent with the cell of origin and CSCs as critical regulators of the pathogenesis of GBM. © 2016 Alcantara Llaguno et al; Published by Cold Spring Harbor Laboratory Press.

Establishment of neurovascular congruency in the mouse whisker system by an independent patterning mechanism.

PubMed

Oh, Won-Jong; Gu, Chenghua

2013-10-16

Nerves and vessels often run parallel to one another, a phenomenon that reflects their functional interdependency. Previous studies have suggested that neurovascular congruency in planar tissues such as skin is established through a "one-patterns-the-other" model, in which either the nervous system or the vascular system precedes developmentally and then instructs the other system to form using its established architecture as a template. Here, we find that, in tissues with complex three-dimensional structures such as the mouse whisker system, neurovascular congruency does not follow the previous model but rather is established via a mechanism in which nerves and vessels are patterned independently. Given the diversity of neurovascular structures in different tissues, guidance signals emanating from a central organizer in the specific target tissue may act as an important mechanism to establish neurovascular congruency patterns that facilitate unique target tissue function. Copyright © 2013 Elsevier Inc. All rights reserved.

Myc inhibition is effective against glioma and reveals a role for Myc in proficient mitosis.

PubMed

Annibali, Daniela; Whitfield, Jonathan R; Favuzzi, Emilia; Jauset, Toni; Serrano, Erika; Cuartas, Isabel; Redondo-Campos, Sara; Folch, Gerard; Gonzàlez-Juncà, Alba; Sodir, Nicole M; Massó-Vallés, Daniel; Beaulieu, Marie-Eve; Swigart, Lamorna B; Mc Gee, Margaret M; Somma, Maria Patrizia; Nasi, Sergio; Seoane, Joan; Evan, Gerard I; Soucek, Laura

2014-08-18

Gliomas are the most common primary tumours affecting the adult central nervous system and respond poorly to standard therapy. Myc is causally implicated in most human tumours and the majority of glioblastomas have elevated Myc levels. Using the Myc dominant negative Omomyc, we previously showed that Myc inhibition is a promising strategy for cancer therapy. Here, we preclinically validate Myc inhibition as a therapeutic strategy in mouse and human glioma, using a mouse model of spontaneous multifocal invasive astrocytoma and its derived neuroprogenitors, human glioblastoma cell lines, and patient-derived tumours both in vitro and in orthotopic xenografts. Across all these experimental models we find that Myc inhibition reduces proliferation, increases apoptosis and remarkably, elicits the formation of multinucleated cells that then arrest or die by mitotic catastrophe, revealing a new role for Myc in the proficient division of glioma cells.

Experience-dependent development of perineuronal nets and chondroitin sulfate proteoglycan receptors in mouse visual cortex.

PubMed

Ye, Qian; Miao, Qing-Long

2013-08-08

Perineuronal nets (PNNs) are extracellular matrix structures consisting of chondroitin sulfate proteoglycans (CSPGs), hyaluronan, link proteins and tenascin-R (Tn-R). They enwrap a subset of GABAergic inhibitory interneurons in the cerebral cortex and restrict experience-dependent cortical plasticity. While the expression profile of PNN components has been widely studied in many areas of the central nervous system of various animal species, it remains unclear how these components are expressed during the postnatal development of mouse primary visual cortex (V1). In the present study, we characterized the developmental time course of the formation of PNNs in the mouse primary visual cortex, using the specific antibodies against the two PNN component proteins aggrecan and tenascin-R, or the lectin Wisteria floribunda agglutinin (WFA) that directly binds to glycosaminoglycan chains of chondroitin sulfate proteoglycans (CSPGs). We found that the fluorescence staining signals of both the WFA staining and the antibody against aggrecan rapidly increased in cortical neurons across layers 2-6 during postnatal days (PD) 10-28 and reached a plateau around PD42, suggesting a full construction of PNNs by the end of the critical period. Co-staining with antibodies to Ca(2+) binding protein parvalbumin (PV) demonstrated that the majority of PNN-surrounding cortical neurons are immunoreactive to PV. Similar expression profile of another PNN component tenascin-R was observed in the development of V1. Dark rearing of mice from birth significantly reduced the density of PNN-surrounding neurons. In addition, the expression of two recently identified CSPG receptors - Nogo receptor (NgR) and leukocyte common antigen-related phosphatase (LAR), showed significant increases from PD14 to PD70 in layer 2-6 of cortical PV-positive interneurons in normal reared mice, but decreased significantly in dark-reared ones. Taken together, these results suggest that PNNs form preferentially in cortical PV-positive interneurons in an experience-dependent manner, and reach full maturation around the end of the critical period of V1 development. © Elsevier B.V. All rights reserved.

A neonatal mouse model for the evaluation of antibodies and vaccines against coxsackievirus A6.

PubMed

Yang, Lisheng; Mao, Qunying; Li, Shuxuan; Gao, Fan; Zhao, Huan; Liu, Yajing; Wan, Junkai; Ye, Xiangzhong; Xia, Ningshao; Cheng, Tong; Liang, Zhenglun

2016-10-01

Coxsackievirus A6 (CA6) can induce atypical hand, foot, and mouth disease, which is characterized by severe rash, onychomadesis and a higher rate of infection in adults. Increasing epidemiological data indicated that outbreaks of CA6-associated hand, foot, and mouth disease have markedly increased worldwide in recent years. However, the current body of knowledge on the infection, pathogenic mechanism, and immunogenicity of CA6 is still very limited. In this study, we established the first neonatal mouse model for the evaluation of antibodies and vaccines against CA6. The CA6 strain CA6/141 could infect a one-day-old BALB/c mouse through intraperitoneal and intracerebral routes. The infected mice developed clinical symptoms, such as inactivity, wasting, hind-limb paralysis and even death. Pathological examination indicated that CA6 showed special tropism to skeletal muscles and skin, but not to nervous system or cardiac muscles. Infections with CA6 could induce vesicles in the dermis without a rash in mice, and the CA6 antigen was mainly localized in hair follicles. The strong tropism of CA6 to the skin may be related to its severe clinical features in infants. This mouse model was further applied to evaluate the efficacy of a therapeutic antibody and an experimental vaccine against CA6. A potential mAb 1D5 could fully protect mice from a lethal CA6 infection and also showed good therapeutic effects in the CA6-infected mice. In addition, an inactivated CA6 vaccine was evaluated through maternal immunization and showed 100% protection of neonatal mice from lethal CA6 challenge. Collectively, these results indicate that this infection model will be a useful tool in future studies on vaccines and antiviral reagents against CA6. Copyright © 2016 Elsevier B.V. All rights reserved.

Three-dimensional distribution of tyrosine hydroxylase, vasopressin and oxytocin neurones in the transparent postnatal mouse brain.

PubMed

Godefroy, D; Dominici, C; Hardin-Pouzet, H; Anouar, Y; Melik-Parsadaniantz, S; Rostène, W; Reaux-Le Goazigo, A

2017-12-01

Over the years, advances in immunohistochemistry techniques have been a critical step in detecting and mapping neuromodulatory substances in the central nervous system. The better quality and specificity of primary antibodies, new staining procedures and the spectacular development of imaging technologies have allowed such progress. Very recently, new methods permitting tissue transparency have been successfully used on brain tissues. In the present study, we combined whole-mount immunostaining for tyrosine hydroxylase (TH), oxytocin (OXT) and arginine vasopressin (AVP), with the iDISCO+ clearing method, light-sheet microscopy and semi-automated counting of three-dimensionally-labelled neurones to obtain a (3D) distribution of these neuronal populations in a 5-day postnatal (P5) mouse brain. Segmentation procedure and 3D reconstruction allowed us, with high resolution, to map TH staining of the various catecholaminergic cell groups and their ascending and descending fibre pathways. We show that TH pathways are present in the whole P5 mouse brain, similar to that observed in the adult rat brain. We also provide new information on the postnatal distribution of OXT and AVP immunoreactive cells in the mouse hypothalamus, and show that, compared to AVP neurones, OXT neurones in the supraoptic (SON) and paraventricular (PVN) nuclei are not yet mature in the early postnatal period. 3D semi-automatic quantitative analysis of the PVN reveals that OXT cell bodies are more numerous than AVP neurones, although their immunoreactive soma have a volume half smaller. More AVP nerve fibres compared to OXT were observed in the PVN and the retrochiasmatic area. In conclusion, the results of the present study demonstrate the utility and the potency of imaging large brain tissues with clearing procedures coupled to novel 3D imaging technologies to study, localise and quantify neurotransmitter substances involved in brain and neuroendocrine functions. © 2017 British Society for Neuroendocrinology.

The olfactory nerve: a shortcut for influenza and other viral diseases into the central nervous system.

PubMed

van Riel, Debby; Verdijk, Rob; Kuiken, Thijs

2015-01-01

The olfactory nerve consists mainly of olfactory receptor neurons and directly connects the nasal cavity with the central nervous system (CNS). Each olfactory receptor neuron projects a dendrite into the nasal cavity on the apical side, and on the basal side extends its axon through the cribriform plate into the olfactory bulb of the brain. Viruses that can use the olfactory nerve as a shortcut into the CNS include influenza A virus, herpesviruses, poliovirus, paramyxoviruses, vesicular stomatitis virus, rabies virus, parainfluenza virus, adenoviruses, Japanese encephalitis virus, West Nile virus, chikungunya virus, La Crosse virus, mouse hepatitis virus, and bunyaviruses. However, mechanisms of transport via the olfactory nerve and subsequent spread through the CNS are poorly understood. Proposed mechanisms are either infection of olfactory receptor neurons themselves or diffusion through channels formed by olfactory ensheathing cells. Subsequent virus spread through the CNS could occur by multiple mechanisms, including trans-synaptic transport and microfusion. Viral infection of the CNS can lead to damage from infection of nerve cells per se, from the immune response, or from a combination of both. Clinical consequences range from nervous dysfunction in the absence of histopathological changes to severe meningoencephalitis and neurodegenerative disease. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Mosaic expression of Atrx in the mouse central nervous system causes memory deficits.

PubMed

Tamming, Renee J; Siu, Jennifer R; Jiang, Yan; Prado, Marco A M; Beier, Frank; Bérubé, Nathalie G

2017-02-01

The rapid modulation of chromatin organization is thought to play a crucial role in cognitive processes such as memory consolidation. This is supported in part by the dysregulation of many chromatin-remodelling proteins in neurodevelopmental and psychiatric disorders. A key example is ATRX, an X-linked gene commonly mutated in individuals with syndromic and nonsyndromic intellectual disability. The consequences of Atrx inactivation for learning and memory have been difficult to evaluate because of the early lethality of hemizygous-null animals. In this study, we evaluated the outcome of brain-specific Atrx deletion in heterozygous female mice. These mice exhibit a mosaic pattern of ATRX protein expression in the central nervous system attributable to the location of the gene on the X chromosome. Although the hemizygous male mice die soon after birth, heterozygous females survive to adulthood. Body growth is stunted in these animals, and they have low circulating concentrations of insulin growth factor 1. In addition, they are impaired in spatial, contextual fear and novel object recognition memory. Our findings demonstrate that mosaic loss of ATRX expression in the central nervous system leads to endocrine defects and decreased body size and has a negative impact on learning and memory. © 2017. Published by The Company of Biologists Ltd.

Nop2 is expressed during proliferation of neural stem cells and in adult mouse and human brain.

PubMed

Kosi, Nina; Alić, Ivan; Kolačević, Matea; Vrsaljko, Nina; Jovanov Milošević, Nataša; Sobol, Margarita; Philimonenko, Anatoly; Hozák, Pavel; Gajović, Srećko; Pochet, Roland; Mitrečić, Dinko

2015-02-09

The nucleolar protein 2 gene encodes a protein specific for the nucleolus. It is assumed that it plays a role in the synthesis of ribosomes and regulation of the cell cycle. Due to its link to cell proliferation, higher expression of Nop2 indicates a worse tumor prognosis. In this work we used Nop2(gt1gaj) gene trap mouse strain. While lethality of homozygous animals suggested a vital role of this gene, heterozygous animals allowed the detection of expression of Nop2 in various tissues, including mouse brain. Histochemistry, immunohistochemistry and immunoelectron microscopy techniques, applied to a mature mouse brain, human brain and on mouse neural stem cells revealed expression of Nop2 in differentiating cells, including astrocytes, as well as in mature neurons. Nop2 was detected in various regions of mouse and human brain, mostly in large pyramidal neurons. In the human, Nop2 was strongly expressed in supragranular and infragranular layers of the somatosensory cortex and in layer III of the cingulate cortex. Also, Nop2 was detected in CA1 and the subiculum of the hippocampus. Subcellular analyses revealed predominant location of Nop2 within the dense fibrillar component of the nucleolus. To test if Nop2 expression correlates to cell proliferation occurring during tissue regeneration, we induced strokes in mice by middle cerebral artery occlusion. Two weeks after stroke, the number of Nop2/nestin double positive cells in the region affected by ischemia and the periventricular zone substantially increased. Our findings suggest a newly discovered role of Nop2 in both mature neurons and in cells possibly involved in the regeneration of nervous tissue. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Calmodulin-regulated adenylyl cyclases and neuromodulation.

PubMed

Xia, Z; Storm, D R

1997-06-01

Coincidence detection and crosstalk between signal transduction systems play very important regulatory roles in the nervous system, particularly in the regulation of transcription. Coupling of the Ca2+ and cAMP regulatory systems by calmodulin-regulated adenylyl cyclases is hypothesized to be important for some forms of synaptic plasticity, neuroendocrine function, and olfactory detection. Recent studies of a mutant mouse deficient in type I calmodulin-sensitive adenylyl cyclase have provided the first evidence that adenylyl cyclases are important for synaptic plasticity, as well as for learning and memory in vertebrates.

Distribution of histaminergic neuronal cluster in the rat and mouse hypothalamus.

PubMed

Moriwaki, Chinatsu; Chiba, Seiichi; Wei, Huixing; Aosa, Taishi; Kitamura, Hirokazu; Ina, Keisuke; Shibata, Hirotaka; Fujikura, Yoshihisa

2015-10-01

Histidine decarboxylase (HDC) catalyzes the biosynthesis of histamine from L-histidine and is expressed throughout the mammalian nervous system by histaminergic neurons. Histaminergic neurons arise in the posterior mesencephalon during the early embryonic period and gradually develop into two histaminergic substreams around the lateral area of the posterior hypothalamus and the more anterior peri-cerebral aqueduct area before finally forming an adult-like pattern comprising five neuronal clusters, E1, E2, E3, E4, and E5, at the postnatal stage. This distribution of histaminergic neuronal clusters in the rat hypothalamus appears to be a consequence of neuronal development and reflects the functional differentiation within each neuronal cluster. However, the close linkage between the locations of histaminergic neuronal clusters and their physiological functions has yet to be fully elucidated because of the sparse information regarding the location and orientation of each histaminergic neuronal clusters in the hypothalamus of rats and mice. To clarify the distribution of the five-histaminergic neuronal clusters more clearly, we performed an immunohistochemical study using the anti-HDC antibody on serial sections of the rat hypothalamus according to the brain maps of rat and mouse. Our results confirmed that the HDC-immunoreactive (HDCi) neuronal clusters in the hypothalamus of rats and mice are observed in the ventrolateral part of the most posterior hypothalamus (E1), ventrolateral part of the posterior hypothalamus (E2), ventromedial part from the medial to the posterior hypothalamus (E3), periventricular part from the anterior to the medial hypothalamus (E4), and diffusely extended part of the more dorsal and almost entire hypothalamus (E5). The stereological estimation of the total number of HDCi neurons of each clusters revealed the larger amount of the rat than the mouse. The characterization of histaminergic neuronal clusters in the hypothalamus of rats and mice may provide useful information for further investigations. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

78 FR 19499 - Request for Information: The National Toxicology Program Requests Information On Assays and...

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2013-04-01

... means adverse outcomes to the nervous system resulting from exposure during any life stage. Special... critical to the development and/or function of the nervous system. The NTP is also interested in receiving... to act as toxicants to the developing or adult nervous systems. Request for Information 1...

Generation of a Tph2 Conditional Knockout Mouse Line for Time- and Tissue-Specific Depletion of Brain Serotonin

PubMed Central

Migliarini, Sara; Pacini, Giulia; Pasqualetti, Massimo

2015-01-01

Serotonin has been gaining increasing attention during the last two decades due to the dual function of this monoamine as key regulator during critical developmental events and as neurotransmitter. Importantly, unbalanced serotonergic levels during critical temporal phases might contribute to the onset of neuropsychiatric disorders, such as schizophrenia and autism. Despite increasing evidences from both animal models and human genetic studies have underpinned the importance of serotonin homeostasis maintenance during central nervous system development and adulthood, the precise role of this molecule in time-specific activities is only beginning to be elucidated. Serotonin synthesis is a 2-step process, the first step of which is mediated by the rate-limiting activity of Tph enzymes, belonging to the family of aromatic amino acid hydroxylases and existing in two isoforms, Tph1 and Tph2, responsible for the production of peripheral and brain serotonin, respectively. In the present study, we generated and validated a conditional knockout mouse line, Tph2 flox/flox, in which brain serotonin can be effectively ablated with time specificity. We demonstrated that the Cre-mediated excision of the third exon of Tph2 gene results in the production of a Tph2 null allele in which we observed the near-complete loss of brain serotonin, as well as the growth defects and perinatal lethality observed in serotonin conventional knockouts. We also revealed that in mice harbouring the Tph2 null allele, but not in wild-types, two distinct Tph2 mRNA isoforms are present, namely Tph2Δ3 and Tph2Δ3Δ4, with the latter showing an in-frame deletion of amino acids 84–178 and coding a protein that could potentially retain non-negligible enzymatic activity. As we could not detect Tph1 expression in the raphe, we made the hypothesis that the Tph2Δ3Δ4 isoform can be at the origin of the residual, sub-threshold amount of serotonin detected in the brain of Tph2 null/null mice. Finally, we set up a tamoxifen administration protocol that allows an efficient, time-specific inactivation of brain serotonin synthesis. On the whole, we generated a suitable genetic tool to investigate how serotonin depletion impacts on time-specific events during central nervous system development and adulthood life. PMID:26291320

Cloning and characterization of mouse ACF7, a novel member of the dystonin subfamily of actin binding proteins.

PubMed

Bernier, G; Mathieu, M; De Repentigny, Y; Vidal, S M; Kothary, R

1996-11-15

We have recently cloned the gene responsible for the mouse neurological disorder dystonia musculorum. The predicted product of this gene, dystonin (Dst), is a neural isoform of bullous pemphigoid antigen 1 (Bpag1) with an N-terminal actin binding domain. Here we report on the cloning and characterization of mouse ACF7. Sequence analysis revealed extended homology of mACF7 with both the actin binding domain (ABD) and the Bpag1 portions of dystonin. Moreover, mACF7 and Dst display similar isoform diversity and encode similar sized transcripts in the nervous system. Phylogenetic analysis of mACF7 and dystonin ABD sequences suggests a recent evolutionary origin and that these proteins form a separate novel subfamily within the beta-spectrin superfamily of actin binding proteins. Given the implication of several actin binding proteins in genetic disorders, it is important to know the pattern of mACF7 expression. mACF7 transcripts are detected principally in lung, brain, spinal cord, skeletal and cardiac muscle, and skin. Intriguingly, mACF7 expression in lung is strongly induced just before birth and is restricted to type II alveolar cells. To determine whether spontaneous mutants that may be defective in mACF7 exist, we have mapped the mACF7 gene to mouse chromosome 4.

Identification of Naegleria fowleri proteins linked to primary amoebic meningoencephalitis.

PubMed

Jamerson, Melissa; Schmoyer, Jacqueline A; Park, Jay; Marciano-Cabral, Francine; Cabral, Guy A

2017-03-01

Naegleria fowleri (N. fowleri) causes primary amoebic meningoencephalitis, a rapidly fatal disease of the central nervous system. N. fowleri can exist in cyst, flagellate or amoebic forms, depending on environmental conditions. The amoebic form can invade the brain following introduction into the nasal passages. When applied intranasally to a mouse model, cultured N. fowleri amoebae exhibit low virulence. However, upon serial passage in mouse brain, the amoebae acquire a highly virulent state. In the present study, a proteomics approach was applied to the identification of N. fowleri amoeba proteins whose expression was associated with the highly virulent state in mice. Mice were inoculated intranasally with axenically cultured amoebae or with mouse-passaged amoebae. Examination by light and electron microscopy revealed no morphological differences. However, mouse-passaged amoebae were more virulent in mice as indicated by exhibiting a two log10 titre decrease in median infective dose 50 (ID50). Scatter plot analysis of amoebic lysates revealed a subset of proteins, the expression of which was associated with highly virulent amoebae. MS-MS indicated that this subset contained proteins that shared homology with those linked to cytoskeletal rearrangement and the invasion process. Invasion assays were performed in the presence of a select inhibitor to expand on the findings. The collective results suggest that N. fowleri gene products linked to cytoskeletal rearrangement and invasion may be candidate targets in the management of primary amoebic meningoencephalitis.

Vasopressin Innervation of the Mouse (Mus musculus) Brain and Spinal Cord

PubMed Central

Rood, Benjamin D.; De Vries, Geert J.

2014-01-01

The neuropeptide vasopressin (AVP) has been implicated in the regulation of numerous physiological and behavioral processes. Although mice have become an important model for studying this regulation, there is no comprehensive description of AVP distribution in the mouse brain and spinal cord. With C57BL/6 mice, we used immunohistochemistry to corroborate the location of AVP-containing cells and to define the location of AVP-containing fibers throughout the mouse central nervous system. We describe AVP-immunoreactive (-ir) fibers in midbrain, hindbrain, and spinal cord areas, which have not previously been reported in mice, including innervation of the ventral tegmental area, dorsal and median raphe, lateral and medial parabrachial, solitary, ventrolateral periaqueductal gray, and interfascicular nuclei. We also provide a detailed description of AVP-ir innervation in heterogenous regions such as the amygdala, bed nucleus of the stria terminalis, and ventral forebrain. In general, our results suggest that, compared with other species, the mouse has a particularly robust and widespread distribution of AVP-ir fibers, which, as in other species, originates from a number of different cell groups in the telencephalon and diencephalon. Our data also highlight the robust nature of AVP innervation in specific regulatory nuclei, such as the ventral tegmental area and dorsal raphe nucleus among others, that are implicated in the regulation of many behaviors. PMID:21456024

[Thyroid hormones and the development of the nervous system].

PubMed

Mussa, G C; Zaffaroni, M; Mussa, F

1990-09-01

The growth and differentiation of the central nervous system are closely related to the presence of iodine and thyroid hormones. During the first trimester of human pregnancy the development of the nervous system depends entirely on the availability of iodine; after 12 week of pregnancy it depends on the initial secretion of iodothyronine by the fetal thyroid gland. During the early stages of the development of the nervous system a thyroid hormone deficit may provoke alterations in the maturation of both noble nervous cells (cortical pyramidal cells, Purkinje cells) and glial cells. Hypothyroidism may lead to cellular hypoplasia and reduced dendritic ramification, gemmules and interneuronal connections. Experimental studies in hypothyroid rats have also shown alterations in the content and organization of neuronal intracytoplasmatic microtubules, the biochemical maturation of synaptosomes and the maturation of nuclear and cytoplasmatic T3 receptors. Excess thyroid hormones during the early stages of development may also cause permanent damage to the central nervous system. Hyperthyroidism may initially induce an acceleration of the maturation processes, including the migration and differentiation of cells, the extension of the dendritic processes and synaptogenesis. An excess of thyroid hormones therefore causes neuronal proliferation to end precociously leading to a reduction of the total number of gemmules. Experimental research and clinical studies have partially clarified the correlation between the maturation of the nervous system and thyroid function during the early stages of development; both a deficit and excess of thyroid hormones may lead to permanent anatomo-functional damage to the central nervous system.(ABSTRACT TRUNCATED AT 250 WORDS)

Mitochondria in the nervous system: From health to disease, Part I.

PubMed

Polster, Brian M; Carrì, Maria Teresa; Beart, Philip M

2017-10-01

In Part I of this Special Issue on "Mitochondria in the Nervous System: From Health to Disease", the editors bring together contributions from experts in brain mitochondrial research to provide an up-to-date overview of mitochondrial functioning in physiology and pathology. The issue provides cutting edge reviews on classical areas of mitochondrial biology that include energy substrate utilization, calcium handling, mitochondria-endoplasmic reticulum communication, and cell death regulation. Additional reviews and original research articles touch upon key mitochondrial defects seen across multiple neurodegenerative conditions, including fragmentation, loss of respiratory capacity, calcium overload, elevated reactive oxygen species generation, perturbed NAD + metabolism, altered protein acetylation, and compromised mitophagy. Emerging links between the genetics of neurodegenerative disorders and disruption in mitochondrial function are discussed, and a new mouse model of Complex I deficiency is described. Finally, novel ways to rescue mitochondrial structure and function in acute and chronic brain injury are explored. Copyright © 2017. Published by Elsevier Ltd.

Polo-like Kinase 2 (PLK2) Phosphorylates α-Synuclein at Serine 129 in Central Nervous System*S⃞

PubMed Central

Inglis, Kelly J.; Chereau, David; Brigham, Elizabeth F.; Chiou, San-San; Schöbel, Susanne; Frigon, Normand L.; Yu, Mei; Caccavello, Russell J.; Nelson, Seth; Motter, Ruth; Wright, Sarah; Chian, David; Santiago, Pamela; Soriano, Ferdie; Ramos, Carla; Powell, Kyle; Goldstein, Jason M.; Babcock, Michael; Yednock, Ted; Bard, Frederique; Basi, Guriqbal S.; Sham, Hing; Chilcote, Tamie J.; McConlogue, Lisa; Griswold-Prenner, Irene; Anderson, John P.

2009-01-01

Several neurological diseases, including Parkinson disease and dementia with Lewy bodies, are characterized by the accumulation of α-synuclein phosphorylated at Ser-129 (p-Ser-129). The kinase or kinases responsible for this phosphorylation have been the subject of intense investigation. Here we submit evidence that polo-like kinase 2 (PLK2, also known as serum-inducible kinase or SNK) is a principle contributor to α-synuclein phosphorylation at Ser-129 in neurons. PLK2 directly phosphorylates α-synuclein at Ser-129 in an in vitro biochemical assay. Inhibitors of PLK kinases inhibited α-synuclein phosphorylation both in primary cortical cell cultures and in mouse brain in vivo. Finally, specific knockdown of PLK2 expression by transduction with short hairpin RNA constructs or by knock-out of the plk2 gene reduced p-Ser-129 levels. These results indicate that PLK2 plays a critical role in α-synuclein phosphorylation in central nervous system. PMID:19004816

Pathogenesis of herpes simplex virus in B cell-suppressed mice: the relative roles of cell-mediated and humoral immunity.

PubMed

Kapoor, A K; Nash, A A; Wildy, P

1982-07-01

B cell responses of Balb/c mice were suppressed using sheep anti-mouse IgM serum. At 4 weeks, both B cell-suppressed and normal littermates were infected in the ear pinna with herpes simplex virus type 1 (HSV-1). The B cell-suppressed mice failed to produce neutralizing herpes antibodies in their sera but had a normal cell-mediated immunity (CMI) response as measured by a delayed hypersensitivity skin test. Although the infection was eliminated from the ear in both B cell-suppressed and normal mice by day 10 after infection, there was an indication that B cell-suppressed mice had a more florid primary infection of the peripheral and central nervous system and also a higher incidence of a latent infection. These results support the hypothesis that antibody is important in restricting the spread of virus to the central nervous system, whereas CMI is important in clearing the primary infection in the ear pinna.

Melanocortin-1 receptor activation is neuroprotective in mouse models of neuroinflammatory disease.

PubMed

Mykicki, Nadine; Herrmann, Alexander M; Schwab, Nicholas; Deenen, René; Sparwasser, Tim; Limmer, Andreas; Wachsmuth, Lydia; Klotz, Luisa; Köhrer, Karl; Faber, Cornelius; Wiendl, Heinz; Luger, Thomas A; Meuth, Sven G; Loser, Karin

2016-10-26

In inflammation-associated progressive neuroinflammatory disorders, such as multiple sclerosis (MS), inflammatory infiltrates containing T helper 1 (T H 1) and T H 17 cells cause demyelination and neuronal degeneration. Regulatory T cells (T reg ) control the activation and infiltration of autoreactive T cells into the central nervous system (CNS). In MS and experimental autoimmune encephalomyelitis (EAE) in mice, T reg function is impaired. We show that a recently approved drug, Nle 4 -d-Phe 7 -α-melanocyte-stimulating hormone (NDP-MSH), induced functional T reg , resulting in amelioration of EAE progression in mice. NDP-MSH also prevented immune cell infiltration into the CNS by restoring the integrity of the blood-brain barrier. NDP-MSH exerted long-lasting neuroprotective effects in mice with EAE and prevented excitotoxic death and reestablished action potential firing in mouse and human neurons in vitro. Neuroprotection by NDP-MSH was mediated via signaling through the melanocortin-1 and orphan nuclear 4 receptors in mouse and human neurons. NDP-MSH may be of benefit in treating neuroinflammatory diseases such as relapsing-remitting MS and related disorders. Copyright © 2016, American Association for the Advancement of Science.

Clonidine transport at the mouse blood-brain barrier by a new H+ antiporter that interacts with addictive drugs.

PubMed

André, Pascal; Debray, Marcel; Scherrmann, Jean-Michel; Cisternino, Salvatore

2009-07-01

Identifying drug transporters and their in vivo significance will help to explain why some central nervous system (CNS) drugs cross the blood-brain barrier (BBB) and reach the brain parenchyma. We characterized the transport of the drug clonidine at the luminal BBB by in situ mouse brain perfusion. Clonidine influx was saturable, followed by Michaelis-Menten kinetics (K(m)=0.62 mmol/L, V(max)=1.76 nmol/sec per g at pH 7.40), and was insensitive to both sodium and trans-membrane potential. In vivo manipulation of intracellular and/or extracellular pH and trans-stimulation showed that clonidine was transported by an H+-coupled antiporter regulated by both proton and clonidine gradients, and that diphenhydramine was also a substrate. Organic cation transporters (Oct1-3), P-gp, and Bcrp did not alter clonidine transport at the BBB in knockout mice. Secondary or tertiary amine CNS compounds such as oxycodone, morphine, diacetylmorphine, methylenedioxyamphetamine (MDMA), cocaine, and nicotine inhibited clonidine transport. However, cationic compounds that interact with choline, Mate, Octn, and Pmat transporters did not. This suggests that clonidine is transported at the luminal mouse BBB by a new H+-coupled reversible antiporter.

A GSK-3β Inhibitor Protects Against Radiation Necrosis in Mouse Brain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Xiaoyu; Perez-Torres, Carlos J.; Thotala, Dinesh

Purpose: To quantify the effectiveness of SB415286, a specific inhibitor of GSK-3β, as a neuroprotectant against radiation-induced central nervous system (brain) necrosis in a mouse model. Methods and Materials: Cohorts of mice were treated with SB415286 or dimethyl sulfoxide (DMSO) prior to irradiation with a single 45-Gy fraction targeted to the left hemisphere (brain) using a gamma knife machine. The onset and progression of radiation necrosis (RN) were monitored longitudinally by noninvasive in vivo small-animal magnetic resonance imaging (MRI) beginning 13 weeks postirradiation. MRI-derived necrotic volumes for SB415286- and DMSO-treated mice were compared. MRI results were supported by correlative histology. Results: Micemore » treated with SB415286 showed significant protection from radiation-induced necrosis, as determined by in vivo MRI with histologic validation. MRI-derived necrotic volumes were significantly smaller at all postirradiation time points in SB415286-treated animals. Although the irradiated hemispheres of the DMSO-treated mice demonstrated many of the classic histologic features of RN, including fibrinoid vascular necrosis, vascular telangiectasia, hemorrhage, and tissue loss, the irradiated hemispheres of the SB415286-treated mice consistently showed only minimal tissue damage. These studies confirmed that treatment with a GSK-3β inhibitor dramatically reduced delayed time-to-onset necrosis in irradiated brain. Conclusions: The unilateral cerebral hemispheric stereotactic radiation surgery mouse model in concert with longitudinal MRI monitoring provided a powerful platform for studying the onset and progression of RN and for developing and testing new neuroprotectants. Effectiveness of SB415286 as a neuroprotectant against necrosis motivates potential clinical trials of it or other GSK-3β inhibitors.« less

Protective effect of enterovirus‑71 (EV71) virus‑like particle vaccine against lethal EV71 infection in a neonatal mouse model.

PubMed

Cao, Lei; Mao, Fengfeng; Pang, Zheng; Yi, Yao; Qiu, Feng; Tian, Ruiguang; Meng, Qingling; Jia, Zhiyuan; Bi, Shengli

2015-08-01

Enterovirus-71 (EV71) is a viral pathogen that causes severe cases of hand, foot and mouth disease (HFMD) among young children, with significant mortality. Effective vaccines against HFMD are urgently required. Several EV71 virus-like particle (VLP) vaccine candidates were found to be protective in the neonatal mouse EV71 challenge model. However, to what extent the VLP vaccine protects susceptible organs against EV71 infection in vivo has remained elusive. In the present study, the comprehensive immunogenicity of a potential EV71 vaccine candidate based on VLPs was evaluated in a neonatal mouse model. Despite lower levels of neutralizing antibodies to EV71 in the sera of VLP-immunized mice compared with those in mice vaccinated with inactivated EV71, the VLP-based vaccine was shown to be able to induce immunoglobulin (Ig)G and IgA memory-associated cellular immune responses to EV71. Of note, the EV71 VLP vaccine candidate was capable of inhibiting viral proliferation in cardiac muscle, skeletal muscle, lung and intestine of immunized mice and provided effective protection against the pathological damage caused by viral attack. In particular, the VLP vaccine was able to inhibit the transportation of EV71 from the central nervous system to the muscle tissue and greatly protected muscle tissue from infection, along with recovery from the viral infection. This led to nearly 100% immunoprotective efficacy, enabling neonatal mice delivered by VLP-immunized female adult mice to survive and grow with good health. The present study provided valuable additional knowledge of the specific protective efficacy of the EV71 VLP vaccine in vivo, which also indicated that it is a promising potential candidate for being developed into an EV71 vaccine.

Different 2-Aminothiazole Therapeutics Produce Distinct Patterns of Scrapie Prion Neuropathology in Mouse Brains.

PubMed

Giles, Kurt; Berry, David B; Condello, Carlo; Hawley, Ronald C; Gallardo-Godoy, Alejandra; Bryant, Clifford; Oehler, Abby; Elepano, Manuel; Bhardwaj, Sumita; Patel, Smita; Silber, B Michael; Guan, Shenheng; DeArmond, Stephen J; Renslo, Adam R; Prusiner, Stanley B

2015-10-01

Because no drug exists that halts or even slows any neurodegenerative disease, developing effective therapeutics for any prion disorder is urgent. We recently reported two compounds (IND24 and IND81) with the 2-aminothiazole (2-AMT) chemical scaffold that almost doubled the incubation times in scrapie prion-infected, wild-type (wt) FVB mice when given in a liquid diet. Remarkably, oral prophylactic treatment with IND24 beginning 14 days prior to intracerebral prion inoculation extended survival from ∼120 days to over 450 days. In addition to IND24, we evaluated the pharmacokinetics and efficacy of five additional 2-AMTs; one was not followed further because its brain penetration was poor. Of the remaining four new 2-AMTs, IND114338 doubled and IND125 tripled the incubation times of RML-inoculated wt and Tg4053 mice overexpressing wt mouse prion protein (PrP), respectively. Neuropathological examination of the brains from untreated controls showed a widespread deposition of self-propagating, β-sheet-rich "scrapie" isoform (PrP(Sc)) prions accompanied by a profound astrocytic gliosis. In contrast, mice treated with 2-AMTs had lower levels of PrP(Sc) and associated astrocytic gliosis, with each compound resulting in a distinct pattern of deposition. Notably, IND125 prevented both PrP(Sc) accumulation and astrocytic gliosis in the cerebrum. Progressive central nervous system dysfunction in the IND125-treated mice was presumably due to the PrP(Sc) that accumulated in their brainstems. Disappointingly, none of the four new 2-AMTs prolonged the lives of mice expressing a chimeric human/mouse PrP transgene inoculated with Creutzfeldt-Jakob disease prions. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Combined therapy with m-TOR-dependent and -independent autophagy inducers causes neurotoxicity in a mouse model of Machado-Joseph disease.

PubMed

Duarte-Silva, S; Silva-Fernandes, A; Neves-Carvalho, A; Soares-Cunha, C; Teixeira-Castro, A; Maciel, P

2016-01-28

A major pathological hallmark in several neurodegenerative disorders, like polyglutamine disorders (polyQ), including Machado-Joseph disease (MJD), is the formation of protein aggregates. MJD is caused by a CAG repeat expansion in the ATXN3 gene, resulting in an abnormal protein, which is prone to misfolding and forms cytoplasmic and nuclear aggregates within neurons, ultimately inducing neurodegeneration. Treatment of proteinopathies with drugs that up-regulate autophagy has shown promising results in models of polyQ diseases. Temsirolimus (CCI-779) inhibits the mammalian target of rapamycin (m-TOR), while lithium chloride (LiCl) acts by inhibiting inositol monophosphatase, both being able to induce autophagy. We have previously shown that chronic treatment with LiCl (10.4 mg/kg) had limited effects in a transgenic MJD mouse model. Also, others have shown that CCI-779 had mild positive effects in a different mouse model of the disease. It has been suggested that the combination of mTOR-dependent and -independent autophagy inducers could be a more effective therapeutic approach. To further explore this avenue toward therapy, we treated CMVMJD135 transgenic mice with a conjugation of CCI-779 and LiCl, both at concentrations known to induce autophagy and not to be toxic. Surprisingly, this combined treatment proved to be deleterious to both wild-type (wt) and transgenic animals, failing to rescue their neurological symptoms and actually exerting neurotoxic effects. These results highlight the possible dangers of manipulating autophagy in the nervous system and suggest that a better understanding of the potential disruption in the autophagy pathway in MJD is required before successful long-term autophagy modulating therapies can be developed. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

'Prion-like' propagation of the synucleinopathy of M83 transgenic mice depends on the mouse genotype and type of inoculum.

PubMed

Sargent, Dorian; Verchère, Jérémy; Lazizzera, Corinne; Gaillard, Damien; Lakhdar, Latifa; Streichenberger, Nathalie; Morignat, Eric; Bétemps, Dominique; Baron, Thierry

2017-10-01

The M83 transgenic mouse is a model of human synucleinopathies that develops severe motor impairment correlated with accumulation of the pathological Ser129-phosphorylated α-synuclein (α-syn P ) in the brain and spinal cord. M83 disease can be accelerated by intracerebral inoculation of brain extracts from sick M83 mice. This has also recently been described using peripheral routes, injecting recombinant preformed α-syn fibrils into the muscle or the peritoneum. Here, we inoculated homozygous and/or hemizygous M83 neonates via the intraperitoneal and/or intracerebral routes with two different brain extracts: one from sick M83 mice inoculated with brain extract from other sick M83 mice, and the other derived from a human multiple system atrophy source passaged in M83 mice. Detection of α-syn P using ELISA and western blot confirmed the disease in mice. The distribution of α-syn P in the central nervous system was similar, independently of the inoculum or inoculation route, consistent with previous studies describing M83 disease. ELISA tests revealed higher levels of α-syn P in homozygous than in hemizygous sick M83 mice, at least after IC inoculation. Interestingly, the immunoreactivity of α-syn P detected by ELISA was significantly lower in M83 mice inoculated with the multiple system atrophy inoculum than in M83 mice inoculated with the M83 inoculum, at the first two passages. 'Prion-like' propagation of the synucleinopathy up to the clinical disease was accelerated by both intracerebral and intraperitoneal inoculations of brain extracts from sick mice. This acceleration, however, depends on the levels of α-syn expression by the mouse and the type of inoculum. © 2017 International Society for Neurochemistry.

Title: Comparative transcriptome profiling of the human and mouse dorsal root ganglia: an RNA-seq-based resource for pain and sensory neuroscience research.

PubMed

Ray, Pradipta; Torck, Andrew; Quigley, Lilyana; Wangzhou, Andi; Neiman, Matthew; Rao, Chandranshu; Lam, Tiffany; Kim, Ji-Young; Kim, Tae Hoon; Zhang, Michael Q; Dussor, Gregory; Price, Theodore J

2018-03-20

Molecular neurobiological insight into human nervous tissues is needed to generate next generation therapeutics for neurological disorders like chronic pain. We obtained human Dorsal Root Ganglia (DRG) samples from organ donors and performed RNA-sequencing (RNA-seq) to study the human DRG (hDRG) transcriptional landscape, systematically comparing it with publicly available data from a variety of human and orthologous mouse tissues, including mouse DRG (mDRG). We characterized the hDRG transcriptional profile in terms of tissue-restricted gene co-expression patterns and putative transcriptional regulators, and formulated an information-theoretic framework to quantify DRG enrichment. Relevant gene families and pathways were also analyzed, including transcription factors (TFs), g-protein coupled receptors (GCPRs) and ion channels. Our analyses reveal a hDRG-enriched protein-coding gene set (∼140), some of which have not been described in the context of DRG or pain signaling. A majority of these show conserved enrichment in mDRG, and were mined for known drug - gene product interactions. Conserved enrichment of the vast majority of TFs suggest that the mDRG is a faithful model system for studying hDRGs, due to evolutionarily conserved regulatory programs. Comparison of hDRG and tibial nerve transcriptomes suggest trafficking of neuronal mRNA to axons in adult hDRG, and are consistent with studies of axonal transport in rodent sensory neurons. We present our work as an online, searchable repository (https://www.utdallas.edu/bbs/painneurosciencelab/sensoryomics/drgtxome), creating a resource for the community. Our analyses provide insight into DRG biology for guiding development of novel therapeutics, and a blueprint for cross-species transcriptomic analyses.

Abnormal Brain Iron Metabolism in Irp2 Deficient Mice Is Associated with Mild Neurological and Behavioral Impairments

PubMed Central

Zumbrennen-Bullough, Kimberly B.; Becker, Lore; Garrett, Lillian; Hölter, Sabine M.; Calzada-Wack, Julia; Mossbrugger, Ilona; Quintanilla-Fend, Leticia; Racz, Ildiko; Rathkolb, Birgit; Klopstock, Thomas; Wurst, Wolfgang; Zimmer, Andreas; Wolf, Eckhard; Fuchs, Helmut; Gailus-Durner, Valerie; de Angelis, Martin Hrabě; Romney, Steven J.; Leibold, Elizabeth A.

2014-01-01

Iron Regulatory Protein 2 (Irp2, Ireb2) is a central regulator of cellular iron homeostasis in vertebrates. Two global knockout mouse models have been generated to explore the role of Irp2 in regulating iron metabolism. While both mouse models show that loss of Irp2 results in microcytic anemia and altered body iron distribution, discrepant results have drawn into question the role of Irp2 in regulating brain iron metabolism. One model shows that aged Irp2 deficient mice develop adult-onset progressive neurodegeneration that is associated with axonal degeneration and loss of Purkinje cells in the central nervous system. These mice show iron deposition in white matter tracts and oligodendrocyte soma throughout the brain. A contrasting model of global Irp2 deficiency shows no overt or pathological signs of neurodegeneration or brain iron accumulation, and display only mild motor coordination and balance deficits when challenged by specific tests. Explanations for conflicting findings in the severity of the clinical phenotype, brain iron accumulation and neuronal degeneration remain unclear. Here, we describe an additional mouse model of global Irp2 deficiency. Our aged Irp2−/− mice show marked iron deposition in white matter and in oligodendrocytes while iron content is significantly reduced in neurons. Ferritin and transferrin receptor 1 (TfR1, Tfrc), expression are increased and decreased, respectively, in the brain from Irp2−/− mice. These mice show impairments in locomotion, exploration, motor coordination/balance and nociception when assessed by neurological and behavioral tests, but lack overt signs of neurodegenerative disease. Ultrastructural studies of specific brain regions show no evidence of neurodegeneration. Our data suggest that Irp2 deficiency dysregulates brain iron metabolism causing cellular dysfunction that ultimately leads to mild neurological, behavioral and nociceptive impairments. PMID:24896637

Ol-Prx 3, a member of an additional class of homeobox genes, is unimodally expressed in several domains of the developing and adult central nervous system of the medaka (Oryzias latipes)

PubMed Central

Joly, Jean-Stephane; Bourrat, Franck; Nguyen, Van; Chourrout, Daniel

1997-01-01

Large-scale genetic screens for mutations affecting early neurogenesis of vertebrates have recently been performed with an aquarium fish, the zebrafish. Later stages of neural morphogenesis have attracted less attention in small fish species, partly because of the lack of molecular markers of developing structures that may facilitate the detection of discrete structural alterations. In this context, we report the characterization of Ol-Prx 3 (Oryzias latipes-Prx 3). This gene was isolated in the course of a large-scale screen for brain cDNAs containing a highly conserved DNA binding region, the homeobox helix-three. Sequence analysis revealed that this gene belongs to another class of homeobox genes, together with a previously isolated mouse ortholog, called OG-12 [Rovescalli, A. C., Asoh, S. & Nirenberg, M. (1996) Proc. Natl. Acad. Sci. USA 93, 10691–10696] and with the human SHOX gene [Rao, E., Weiss, B., Fukami, M., Rump, A., Niesler, B., et al. (1997) Nat. Genet. 16, 54–62], thought to be involved in the short-stature phenotype of Turner syndrome patients. These three genes exhibit a moderate level of identity in the homeobox with the other genes of the paired-related (PRX) gene family. Ol-Prx 3, as well as the PRX genes, are expressed in various cartilaginous structures of head and limbs. These genes might thus be involved in common regulatory pathways during the morphogenesis of these structures. Moreover, this paper reports a complex and monophasic pattern of Ol-Prx 3 expression in the central nervous system, which differs markedly from the patterns reported for the PRX genes, Prx 3 excluded: this gene begins to be expressed in a variety of central nervous system territories at late neurula stage. Strikingly, it remains turned on in some of the derivatives of each territory during the entire life of the fish. We hope this work will thus help identify common features for the PRX 3 family of homeobox genes. PMID:9371787

Neuropeptide Y Negatively Influences Monocyte Recruitment to the Central Nervous System during Retrovirus Infection.

PubMed

Woods, Tyson A; Du, Min; Carmody, Aaron; Peterson, Karin E

2015-12-30

Monocyte infiltration into the CNS is a hallmark of several viral infections of the central nervous system (CNS), including retrovirus infection. Understanding the factors that mediate monocyte migration in the CNS is essential for the development of therapeutics that can alter the disease process. In the current study, we found that neuropeptide Y (NPY) suppressed monocyte recruitment to the CNS in a mouse model of polytropic retrovirus infection. NPY(-/-) mice had increased incidence and kinetics of retrovirus-induced neurological disease, which correlated with a significant increase in monocytes in the CNS compared to wild-type mice. Both Ly6C(hi) inflammatory and Ly6C(lo) alternatively activated monocytes were increased in the CNS of NPY(-/-) mice following virus infection, suggesting that NPY suppresses the infiltration of both cell types. Ex vivo analysis of myeloid cells from brain tissue demonstrated that infiltrating monocytes expressed high levels of the NPY receptor Y2R. Correlating with the expression of Y2R on monocytes, treatment of NPY(-/-) mice with a truncated, Y2R-specific NPY peptide suppressed the incidence of retrovirus-induced neurological disease. These data demonstrate a clear role for NPY as a negative regulator of monocyte recruitment into the CNS and provide a new mechanism for suppression of retrovirus-induced neurological disease. Monocyte recruitment to the brain is associated with multiple neurological diseases. However, the factors that influence the recruitment of these cells to the brain are still not well understood. In the current study, we found that neuropeptide Y, a protein produced by neurons, affected monocyte recruitment to the brain during retrovirus infection. We show that mice deficient in NPY have increased influx of monocytes into the brain and that this increase in monocytes correlates with neurological-disease development. These studies provide a mechanism by which the nervous system, through the production of NPY, can suppress monocyte trafficking to the brain and reduce retrovirus-induced neurological disease. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

The effects of aging on the BTBR mouse model of autism spectrum disorder

PubMed Central

Jasien, Joan M.; Daimon, Caitlin M.; Wang, Rui; Shapiro, Bruce K.; Martin, Bronwen; Maudsley, Stuart

2014-01-01

Autism spectrum disorder (ASD) is a complex heterogeneous neurodevelopmental disorder characterized by alterations in social functioning, communicative abilities, and engagement in repetitive or restrictive behaviors. The process of aging in individuals with autism and related neurodevelopmental disorders is not well understood, despite the fact that the number of individuals with ASD aged 65 and older is projected to increase by over half a million individuals in the next 20 years. To elucidate the effects of aging in the context of a modified central nervous system, we investigated the effects of age on the BTBR T + tf/j mouse, a well characterized and widely used mouse model that displays an ASD-like phenotype. We found that a reduction in social behavior persists into old age in male BTBR T + tf/j mice. We employed quantitative proteomics to discover potential alterations in signaling systems that could regulate aging in the BTBR mice. Unbiased proteomic analysis of hippocampal and cortical tissue of BTBR mice compared to age-matched wild-type controls revealed a significant decrease in brain derived neurotrophic factor and significant increases in multiple synaptic markers (spinophilin, Synapsin I, PSD 95, NeuN), as well as distinct changes in functional pathways related to these proteins, including “Neural synaptic plasticity regulation” and “Neurotransmitter secretion regulation.” Taken together, these results contribute to our understanding of the effects of aging on an ASD-like mouse model in regards to both behavior and protein alterations, though additional studies are needed to fully understand the complex interplay underlying aging in mouse models displaying an ASD-like phenotype. PMID:25225482

Improving and Accelerating Drug Development for Nervous System Disorders

PubMed Central

Pankevich, Diana E.; Altevogt, Bruce M.; Dunlop, John; Gage, Fred H.; Hyman, Steve E.

2014-01-01

Advances in the neurosciences have placed the field in the position where it is poised to significantly reduce the burden of nervous system disorders. However, drug discovery, development and translation for nervous system disorders still pose many unique challenges. The key scientific challenges can be summarized as follows: mechanisms of disease, target identification and validation, predictive models, biomarkers for patient stratification and as endpoints for clinical trials, clear regulatory pathways, reliability and reproducibility of published data, and data sharing and collaboration. To accelerate nervous system drug development the Institute of Medicine’s Forum on Neuroscience and Nervous System Disorders has hosted a series of public workshops that brought together representatives of industry, government (including both research funding and regulatory agencies), academia, and patient groups to discuss these challenges and offer potential strategies to improve the translational neuroscience. PMID:25442933

Compensatory molecular and functional mechanisms in nervous system of the Grm1(crv4) mouse lacking the mGlu1 receptor: a model for motor coordination deficits.

PubMed

Rossi, Pia Irene Anna; Musante, Ilaria; Summa, Maria; Pittaluga, Anna; Emionite, Laura; Ikehata, Masami; Rastaldi, Maria Pia; Ravazzolo, Roberto; Puliti, Aldamaria

2013-09-01

The metabotropic glutamate type 1 (mGlu1) and type 5 (mGlu5) receptors, the only members of group I mGlu receptors, are implicated in synaptic plasticity and mechanisms of feedback control of glutamate release. They exhibit nearly complementary distributions throughout the central nervous system, well evident in the cerebellum, where mGlu1 receptor is most intensely expressed while mGlu5 receptor is not. Despite their different distribution, they show a similar subcellular localization and use common transducing pathways. We recently described the Grm1(crv4) mouse with motor coordination deficits and renal anomalies caused by a spontaneous mutation inactivating the mGlu1 receptor. To define the neuropathological mechanisms in these mice, we evaluated expression and function of the mGlu5 receptor in cerebral and cerebellar cortices. Western blot and immunofluorescence analyses showed mGlu5 receptor overexpression. Quantitative reverse transcriptase-polymerase chain reaction results indicated that the up-regulation is already evident at RNA level. Functional studies confirmed an enhanced glutamate release from cortical cerebral and cerebellar synaptosomes when compared with wild-type that is abolished by the mGlu5 receptor-specific inhibitor, 2-methyl-6-(phenylethynyl) pyridine hydrochloride (MPEP). Finally, acute MPEP treatment of Grm1(crv4/crv4) mice induced an evident although incomplete improvement of motor coordination, suggesting that mGlu5 receptors enhanced activity worsens, instead of improving, the motor-coordination defects in the Grm1(crv4/crv4) mice.

Glycogen function in adult central and peripheral nerves.

PubMed

Evans, Richard D; Brown, Angus M; Ransom, Bruce R

2013-08-01

We studied the roles of glycogen in axonal pathways of the central nervous system (CNS) and peripheral nervous system (PNS). By using electrophysiological recordings, in combination with biochemical glycogen assay, it was possible to determine whether glycogen was crucial to axon function under different conditions. Glycogen was present both in mouse optic nerve (MON) and in mouse sciatic nerve (MSN). Aglycemia caused loss of the compound action potential (CAP) in both pathways after a latency of 15 min (MON) and 120 min for myelinated axons (A fibers) in the MSN. With the exception of unmyelinated axons (C fibers) in the MSN, CAP decline began when usable glycogen was exhausted. Glycogen was located in astrocytes in the MON and in myelinating Schwann cells in the MSN; it was absent from the Schwann cells surrounding unmyelinated C fibers. In MON, astrocytic glycogen is metabolized to lactate and "shuttled" to axons to support metabolism. The ability of lactate to support A fiber conduction in the absence of glucose suggests a common pathway in both the CNS and the PNS. Lactate is released from MON and MSN in substantial quantities. That lactate levels fall in MSN in the presence of diaminobenzidine, which inhibits glycogen phosphorylase, strongly suggests that glycogen metabolism contributes to lactate release under resting conditions. Glycogen is a "backup" energy substrate in both the CNS and the PNS and, beyond sustaining excitability during glucose deprivation, has the capacity to subsidize the axonal energy demands during times of intense activity in the presence of glucose. Copyright © 2013 Wiley Periodicals, Inc.

Acute Effect of Pore-Forming Clostridium perfringens ε-Toxin on Compound Action Potentials of Optic Nerve of Mouse.

PubMed

Cases, Mercè; Llobet, Artur; Terni, Beatrice; Gómez de Aranda, Inmaculada; Blanch, Marta; Doohan, Briain; Revill, Alexander; Brown, Angus M; Blasi, Juan; Solsona, Carles

2017-01-01

ε-Toxin is a pore forming toxin produced by Clostridium perfringens types B and D. It is synthesized as a less active prototoxin form that becomes fully active upon proteolytic activation. The toxin produces highly lethal enterotoxaemia in ruminants, has the ability to cross the blood-brain barrier (BBB) and specifically binds to myelinated fibers. We discovered that the toxin induced a release of ATP from isolated mice optic nerves, which are composed of myelinated fibers that are extended from the central nervous system. We also investigated the effect of the toxin on compound action potentials (CAPs) in isolated mice optic nerves. When nerves were stimulated at 100 Hz during 200 ms, the decrease of the amplitude and the area of the CAPs was attenuated in the presence of ε-toxin. The computational modelling of myelinated fibers of mouse optic nerve revealed that the experimental results can be mimicked by an increase of the conductance of myelin and agrees with the pore forming activity of the toxin which binds to myelin and could drill it by making pores. The intimate ultrastructure of myelin was not modified during the periods of time investigated. In summary, the acute action of the toxin produces a subtle functional impact on the propagation of the nerve action potential in myelinated fibers of the central nervous system with an eventual desynchronization of the information. These results may agree with the hypothesis that the toxin could be an environmental trigger of multiple sclerosis (MS).

Acute Effect of Pore-Forming Clostridium perfringens ε-Toxin on Compound Action Potentials of Optic Nerve of Mouse

PubMed Central

Terni, Beatrice; Gómez de Aranda, Inmaculada; Blanch, Marta; Brown, Angus M.

2017-01-01

ε-Toxin is a pore forming toxin produced by Clostridium perfringens types B and D. It is synthesized as a less active prototoxin form that becomes fully active upon proteolytic activation. The toxin produces highly lethal enterotoxaemia in ruminants, has the ability to cross the blood–brain barrier (BBB) and specifically binds to myelinated fibers. We discovered that the toxin induced a release of ATP from isolated mice optic nerves, which are composed of myelinated fibers that are extended from the central nervous system. We also investigated the effect of the toxin on compound action potentials (CAPs) in isolated mice optic nerves. When nerves were stimulated at 100 Hz during 200 ms, the decrease of the amplitude and the area of the CAPs was attenuated in the presence of ε-toxin. The computational modelling of myelinated fibers of mouse optic nerve revealed that the experimental results can be mimicked by an increase of the conductance of myelin and agrees with the pore forming activity of the toxin which binds to myelin and could drill it by making pores. The intimate ultrastructure of myelin was not modified during the periods of time investigated. In summary, the acute action of the toxin produces a subtle functional impact on the propagation of the nerve action potential in myelinated fibers of the central nervous system with an eventual desynchronization of the information. These results may agree with the hypothesis that the toxin could be an environmental trigger of multiple sclerosis (MS). PMID:28798954

The pathogenesis of poliomyelitis: what we don't know.

PubMed

Nathanson, Neal

2008-01-01

Poliomyelitis has long served as a model for studies of viral pathogenesis, but there remain many important gaps in our understanding of this disease. It is the intent of this review to highlight these residual but important questions, in light of a possible future moratorium on research with polioviruses. Salient questions include: (1) What cells in the gastrointestinal tract are initially infected and act as the source of excreted virus? (2) What is the receptor used by mouse-adapted strains of poliovirus and how can some polioviruses use both mouse and primate receptors? (3) What determines species differences in susceptibility of the gastrointestinal tract to polioviruses? Why cannot PVR transgenic mice be infected by the natural enteric route? (4) Why are neuroadapted polioviruses unable to infect nonneural cells? (5) What is the role of postentry blocks in replication as determinants of neurovirulence? (6) What route(s) does poliovirus take to enter the central nervous system and how does it cross the blood-brain barrier? (7) Why does poliovirus preferentially attack lower motor neurons in contrast to many other neuronal types within the central nervous system? (8) Does cellular immunity play any role in recovery from acute infection or in vaccine-induced protection? (9) In which cells does poliovirus persist in patients with gamma-globulin deficiencies? (10) Is there any evidence that poliovirus genomes can persist in immunocompetent hosts? (11) Why has type 2 poliovirus been eradicated while types 1 and 3 have not? (12) Can transmission of vaccine-derived polioviruses be prevented with inactivated poliovirus vaccine? (13) What is the best strategy to control and eliminate vaccine-derived polioviruses?

[ASSESSMENT OF PEFORMANCE IN STUDENTS WITH DIFFERENT TYPES OF THE NERVOUS SYSTEM WITH THE USE OF THE DEVELOPED SOFTWARE FOR PC "TAPPING-TEST"].

PubMed

Shumskikh, D S; Rakhmanov, R S; Orlov, A L

2015-01-01

There was developed the PC software, which demonstrates the type of nervous system, allows us to differentiate people according to the empirical coefficient within groups with the same type of nervous system, provides information on the severity of the asymmetry of the hemispheres of the brain and shows the results of performance of the work It does not require additional calculations. With its use there were examined 1 and 2 courses students of the institution. Ehpyky was performed the comparative analysis of the progress of students with different types of nervous system. The academic performance in the examinees with a strong type of nervous system was significantly higher than in those with a weak type. In order to improve professional training the assessment of the type of the nervous system can be used in the educational process for the identification and correction of students with a weak nervous system.

The proof-of-concept of ASS234: Peripherally administered ASS234 enters the central nervous system and reduces pathology in a male mouse model of Alzheimer disease.

PubMed

Serrano, Mari Paz; Herrero-Labrador, Raquel; Futch, Hunter S; Serrano, Julia; Romero, Alejandro; Fernandez, Ana Patricia; Samadi, Abdelouahid; Unzeta, Mercedes; Marco-Contelles, Jose; Martínez-Murillo, Ricardo

2017-01-01

The heterogeneity of Alzheimer disease requires the development of multitarget drugs for treating the symptoms of the disease and its progression. Both cholinergic and monoamine oxidase dysfunctions are involved in the pathological process. Thus, we hypothesized that the development of therapies focused on these targets might be effective. We have developed and assessed a new product, coded ASS234, a multipotent acetyl and butyrylcholinesterase/monoamine oxidase A-B inhibitor with a potent inhibitory effect on amyloid-β aggregation as well as antioxidant and antiapoptotic properties. But there is a need to reliably correlate in vitro and in vivo drug release data. We examined the effect of ASS234 on cognition in healthy adult C57BL/6J mice in a model of scopolamine-induced cognitive impairment that often accompanies normal and pathological aging. Also, in a characterized transgenic APPswe/PS1ΔE9 mouse model of Alzheimer disease, we examined the effects of short-term ASS234 treatment on plaque deposition and gliosis using immunohistochemistry. Toxicology of ASS234 was assessed using a quantitative high-throughput in vitro cytotoxicity screening assay following the MTT assay method in HepG2 liver cells. In vivo, ASS234 significantly decreased scopolamine-induced learning deficits in C57BL/6J mice. Also, reduction of amyloid plaque burden and gliosis in the cortex and hippocampus was assessed. In vitro, ASS234 exhibited lesser toxicity than donepezil and tacrine. The study was conducted in male mice only. Although the Alzheimer disease model does not recapitulate all features of the human disease, it exhibits progressive monoaminergic neurodegeneration. ASS234 is a promising alternative drug of choice to treat the cognitive decline and neurodegeneration underlying Alzheimer disease.

Specific Distribution of the Autophagic Protein GABARAPL1/GEC1 in the Developing and Adult Mouse Brain and Identification of Neuronal Populations Expressing GABARAPL1/GEC1

PubMed Central

Le Grand, Jaclyn Nicole; Bon, Karine; Fraichard, Annick; Zhang, Jianhua; Jouvenot, Michèle; Risold, Pierre-Yves; Boyer-Guittaut, Michaël; Delage-Mourroux, Régis

2013-01-01

Macroautophagy is a highly conserved cellular degradation process, regulated by autophagy-related (atg) factors, in which a double membrane autophagosome engulfs cytoplasmic components to target them for degradation. In yeast, the Atg8 protein is indispensable for autophagosome formation. In mammals, this is complicated by the presence of six Atg8 homologues grouped into the GABARAP and MAP1LC3 subfamilies. Although these proteins share a high similarity, their transcript expression, regulation and protein interactions differ, suggesting they may display individual properties and specific functions. GABARAPL1/GEC1 is a member of the GABARAP subfamily and its mRNA is the most highly expressed Atg8 homologue in the central nervous system. Consequently, we performed an in depth study of GABARAPL1 distribution in the developing and adult murine brain. Our results show that GABARAPL1 brain expression is visible as early as embryonic day 11 and progressively increases to a maximum level in the adult. Immunohistochemical staining was detected in both fibers and immature neurons in embryos but was restrained to neurons in adult tissue. By E17, intense punctate-like structures were visible and these accumulated in cortical primary neurons treated with the autophagosome/lysosome fusion inhibitor Bafilomycin A1 (Baf A1), suggesting that they represent autophagosomes. Finally, GABARAPL1 expression was particularly intense in motoneurons in the embryo and in neurons involved in somatomotor and neuroendocrine functions in the adult, particularly in the substantia nigra pars compacta, a region affected in Parkinson's disease. Our study of cerebral GABARAPL1 protein expression provides insight into its role in the development and homeostasis of the mouse brain. PMID:23690988

Cerebral protein kinase C and its mRNA level in apolipoprotein E-deficient mice.

PubMed

Hung, M C; Hayase, K; Yoshida, R; Sato, M; Imaizumi, K

2001-08-10

It is known that protein kinase C (PKC) activity may be one of the fundamental cellular changes associated with memory function. Apolipoprotein E (apoE) deficiency causes cholinergic deficits and memory impairment. ApoE-deficient mouse has been employed as a serviceable model for studying the relation between apoE and the memory deficit induced by cholinergic impairment. Brain-fatty acid binding protein (b-FABP) might be functional during development of the nervous system. Peroxisome proliferator-activated receptor (PPAR) is involved in the early change in lipid metabolism. We investigated the alterations not only in cerebral PKC activity, but also in the gene expressions of PKC-beta, brain-FABP and PPAR-alpha in apoE-deficient mice. The results showed that there was a lower cerebral membrane-bound PKC activity in the apoE-deficient mice than in its wild type strain (C57BL/6). But there were no significant differences in cytosolic PKC activity. PKC-beta, b-FABP and PPAR-alpha mRNA expressions in cerebrum were lowered in apoE-deficient mice. These findings may be involved in the dysfunction of the brain neurotransmission system in apoE-deficient mouse. Alternatively, these results also suggest that cerebral apoE plays an important role in brain PKC activation by maintaining an appropriate expression of b-FABP and PPAR-alpha mRNAs.

The spatiotemporal relationships between chondroitin sulfate proteoglycans and terminations of calcitonin gene related peptide and parvalbumin immunoreactive afferents in the spinal cord of mouse embryos.

PubMed

Wang, Liqing; Yu, Chao; Wang, Jun; Zhao, Hui; Chan, Sun-On

2017-08-10

Chondroitin sulfate (CS) proteoglycans (PGs) are a family of complex molecules in the extracellular matrix and cell surface that regulate axon growth and guidance during development of the central nervous system. In this study, the expression of CSPGs was investigated in the mouse spinal cord at late embryonic and neonatal stages using CS-56 antibody. CS immunoreactivity was observed abundantly in ventral regions of spinal cord of embryonic day (E) 15 embryos. At E16 to E18, CS expression spread dorsally, but never reached the superficial layers of the dorsal horn. This pattern was maintained until postnatal day 4, the latest stage examined. Antibodies against calcitonin gene related peptide (CGRP) and parvalbumin (PV) were employed to label primary afferents from nociceptors and proprioceptors, respectively. CGRP-immunoreactive fibers terminated in the superficial regions of the dorsal horn where CSPGs were weakly expressed, whereas PV-immunoreactive fibers were found in CSPG-rich regions in the ventral horn. Therefore, we conclude that CS expression is spatiotemporally regulated in the spinal cord, which correlates to the termination of sensory afferents. This pattern suggests a role of CSPGs on patterning afferents in the spinal cord, probably through a differential response of axons to these growth inhibitory molecules. Copyright © 2017 Elsevier B.V. All rights reserved.

A surrogate analyte method to determine D-serine in mouse brain using liquid chromatography-tandem mass spectrometry.

PubMed

Kinoshita, Kohnosuke; Jingu, Shigeji; Yamaguchi, Jun-ichi

2013-01-15

A bioanalytical method for determining endogenous d-serine levels in the mouse brain using a surrogate analyte and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. [2,3,3-(2)H]D-serine and [(15)N]D-serine were used as a surrogate analyte and an internal standard, respectively. The surrogate analyte was spiked into brain homogenate to yield calibration standards and quality control (QC) samples. Both endogenous and surrogate analytes were extracted using protein precipitation followed by solid phase extraction. Enantiomeric separation was achieved on a chiral crown ether column with an analysis time of only 6 min without any derivatization. The column eluent was introduced into an electrospray interface of a triple-quadrupole mass spectrometer. The calibration range was 1.00 to 300 nmol/g, and the method showed acceptable accuracy and precision at all QC concentration levels from a validation point of view. In addition, the brain d-serine levels of normal mice determined using this method were the same as those obtained by a standard addition method, which is time-consuming but is often used for the accurate measurement of endogenous substances. Thus, this surrogate analyte method should be applicable to the measurement of d-serine levels as a potential biomarker for monitoring certain effects of drug candidates on the central nervous system. Copyright © 2012 Elsevier Inc. All rights reserved.

On the morphology of the central nervous system in larval stages of Carcinus maenas L. (Decapoda, Brachyura)

NASA Astrophysics Data System (ADS)

Harzsch, S.; Dawirs, R. R.

1993-02-01

We investigated the morphology of the central nervous system throughout the larval development of Carcinus maenas. For that purpose single larvae were reared in the laboratory from hatching through metamorphosis. Complete series of whole mout semithin sections were obtained from individuals of all successive larval stages and analysed with a light microscope. Morphological feature and spatial arrangement of discernable neural cell clusters, fibre tracts and neuropile are described and compared with the adult pattern. We found that most of the morphological features characterizing the adult nervous system are already present in the zoea-1. Nevertheless, there are marked differences with respect to the arrangement of nerve cell bodies, organization of cerebral neuropile, and disposition of ganglia in the ventral nerve cord. It appears that complexity of the central nervous neuropile is selectively altered during postmetamorphotic development, probably reflecting adaptive changes of sensory-motor integration in response to behavioural maturation. In contrast, during larval development there was little change in the overall structural organization of the central nervous system despite some considerable growth. However, the transition from zoea-4 to megalopa brings about multiple fundamental changes in larval morphology and behavioural pattern. Since central nervous integration should properly adapt to the altered behavioural repertoire of the megalopa, it seems necessary to ask in which respect synaptic rearrangement might characterize development of the central nervous system.

Expression of the LIM-Homeodomain Protein Isl1 in the Developing and Mature Mouse Retina

PubMed Central

Elshatory, Yasser; Deng, Min; Xie, Xiaoling; Gan, Lin

2010-01-01

The mammalian retina is comprised of six major neuronal cell types and is subdivided into more morphological and physiological subtypes. The transcriptional machinery underlying these subtype fate choices is largely unknown. The LIM-homeodomain protein, Isl1, plays an essential role in central nervous system (CNS) differentiation but its relationship to retinal neurogenesis remains unknown. We report here its dynamic spatiotemporal expression in the mouse retina. Among bipolar interneurons, Isl1 expression commences at postnatal day (P)5 and is later restricted to ON-bipolar cells. The intensity of Isl1 expression is found to segregate the pool of ON-bipolar cells into rod and ON-cone bipolar cells with higher expression in rod bipolar cells. As bipolar cell development proceeds from P5–10 the colocalization of Isl1 and the pan-bipolar cell marker Chx10 reveals the organization of ON-center bipolar cell nuclei to the upper portion of the inner nuclear layer. Further, whereas Isl1 is predominantly a ganglion cell marker prior to embryonic day (E)15.5, at E15.5 and later its expression in nonganglion cells expands. We demonstrate that these Isl1-positive, nonganglion cells acquire the expression of amacrine cell markers embryonically, likely representing nascent cholinergic amacrine cells. Taken together, Isl1 is expressed during the maturation of and is later maintained in retinal ganglion cells and subtypes of amacrine and bipolar cells where it may function in the maintenance of these cells into adulthood. J. Comp. Neurol. 503: 182–197, 2007. PMID:17480014

Tissue tropisms, infection kinetics, histologic lesions, and antibody response of the MR766 strain of Zika virus in a murine model.

PubMed

Kawiecki, Anna B; Mayton, E Handly; Dutuze, M Fausta; Goupil, Brad A; Langohr, Ingeborg M; Del Piero, Fabio; Christofferson, Rebecca C

2017-04-18

The appearance of severe Zika virus (ZIKV) disease in the most recent outbreak has prompted researchers to respond through the development of tools to quickly characterize transmission and pathology. We describe here another such tool, a mouse model of ZIKV infection and pathogenesis using the MR766 strain of virus that adds to the growing body of knowledge regarding ZIKV kinetics in small animal models. We infected mice with the MR766 strain of ZIKV to determine infection kinetics via serum viremia. We further evaluated infection-induced lesions via histopathology and visualized viral antigen via immunohistochemical labeling. We also investigated the antibody response of recovered animals to both the MR766 and a strain from the current outbreak (PRVABC59). We demonstrate that the IRF3/7 DKO mouse is a susceptible, mostly non-lethal model well suited for the study of infection kinetics, pathological progression, and antibody response. Infected mice presented lesions in tissues that have been associated with ZIKV infection in the human population, such as the eyes, male gonads, and central nervous system. In addition, we demonstrate that infection with the MR766 strain produces cross-neutralizing antibodies to the PRVABC59 strain of the Asian lineage. This model provides an additional tool for future studies into the transmission routes of ZIKV, as well as for the development of antivirals and other therapeutics, and should be included in the growing list of available tools for investigations of ZIKV infection and pathogenesis.

New tools for the analysis of glial cell biology in Drosophila.

PubMed

Awasaki, Takeshi; Lee, Tzumin

2011-09-01

Because of its genetic, molecular, and behavioral tractability, Drosophila has emerged as a powerful model system for studying molecular and cellular mechanisms underlying the development and function of nervous systems. The Drosophila nervous system has fewer neurons and exhibits a lower glia:neuron ratio than is seen in vertebrate nervous systems. Despite the simplicity of the Drosophila nervous system, glial organization in flies is as sophisticated as it is in vertebrates. Furthermore, fly glial cells play vital roles in neural development and behavior. In addition, powerful genetic tools are continuously being created to explore cell function in vivo. In taking advantage of these features, the fly nervous system serves as an excellent model system to study general aspects of glial cell development and function in vivo. In this article, we review and discuss advanced genetic tools that are potentially useful for understanding glial cell biology in Drosophila. Copyright © 2011 Wiley-Liss, Inc.

Als2 mRNA splicing variants detected in KO mice rescue severe motor dysfunction phenotype in Als2 knock-down zebrafish.

PubMed

Gros-Louis, Francois; Kriz, Jasna; Kabashi, Edor; McDearmid, Jonathan; Millecamps, Stéphanie; Urushitani, Makoto; Lin, Li; Dion, Patrick; Zhu, Qinzhang; Drapeau, Pierre; Julien, Jean-Pierre; Rouleau, Guy A

2008-09-01

Recessive ALS2 mutations are linked to three related but slightly different neurodegenerative disorders: amyotrophic lateral sclerosis, hereditary spastic paraplegia and primary lateral sclerosis. To investigate the function of the ALS2 encoded protein, we generated Als2 knock-out (KO) mice and zAls2 knock-down zebrafish. The Als2(-/-) mice lacking exon 2 and part of exon 3 developed mild signs of neurodegeneration compatible with axonal transport deficiency. In contrast, zAls2 knock-down zebrafish had severe developmental abnormalities, swimming deficits and motor neuron perturbation. We identified, by RT-PCR, northern and western blotting novel Als2 transcripts in mouse central nervous system. These Als2 transcripts were present in Als2 null mice as well as in wild-type littermates and some rescued the zebrafish phenotype. Thus, we speculate that the newly identified Als2 mRNA species prevent the Als2 KO mice from developing severe neurodegenerative disease and might also regulate the severity of the motor neurons phenotype observed in ALS2 patients.

Akt1-Inhibitor of DNA binding2 is essential for growth cone formation and axon growth and promotes central nervous system axon regeneration

PubMed Central

Ko, Hyo Rim; Kwon, Il-Sun; Hwang, Inwoo; Jin, Eun-Ju; Shin, Joo-Ho; Brennan-Minnella, Angela M; Swanson, Raymond; Cho, Sung-Woo; Lee, Kyung-Hoon; Ahn, Jee-Yin

2016-01-01

Mechanistic studies of axon growth during development are beneficial to the search for neuron-intrinsic regulators of axon regeneration. Here, we discovered that, in the developing neuron from rat, Akt signaling regulates axon growth and growth cone formation through phosphorylation of serine 14 (S14) on Inhibitor of DNA binding 2 (Id2). This enhances Id2 protein stability by means of escape from proteasomal degradation, and steers its localization to the growth cone, where Id2 interacts with radixin that is critical for growth cone formation. Knockdown of Id2, or abrogation of Id2 phosphorylation at S14, greatly impairs axon growth and the architecture of growth cone. Intriguingly, reinstatement of Akt/Id2 signaling after injury in mouse hippocampal slices redeemed growth promoting ability, leading to obvious axon regeneration. Our results suggest that Akt/Id2 signaling is a key module for growth cone formation and axon growth, and its augmentation plays a potential role in CNS axonal regeneration. DOI: http://dx.doi.org/10.7554/eLife.20799.001 PMID:27938661

Growing up in a Bubble: Using Germ-Free Animals to Assess the Influence of the Gut Microbiota on Brain and Behavior

PubMed Central

Luczynski, Pauline; McVey Neufeld, Karen-Anne; Oriach, Clara Seira; Clarke, Gerard; Dinan, Timothy G.

2016-01-01

There is a growing recognition of the importance of the commensal intestinal microbiota in the development and later function of the central nervous system. Research using germ-free mice (mice raised without any exposure to microorganisms) has provided some of the most persuasive evidence for a role of these bacteria in gut-brain signalling. Key findings show that the microbiota is necessary for normal stress responsivity, anxiety-like behaviors, sociability, and cognition. Furthermore, the microbiota maintains central nervous system homeostasis by regulating immune function and blood brain barrier integrity. Studies have also found that the gut microbiota influences neurotransmitter, synaptic, and neurotrophic signalling systems and neurogenesis. The principle advantage of the germ-free mouse model is in proof-of-principle studies and that a complete microbiota or defined consortiums of bacteria can be introduced at various developmental time points. However, a germ-free upbringing can induce permanent neurodevelopmental deficits that may deem the model unsuitable for specific scientific queries that do not involve early-life microbial deficiency. As such, alternatives and complementary strategies to the germ-free model are warranted and include antibiotic treatment to create microbiota-deficient animals at distinct time points across the lifespan. Increasing our understanding of the impact of the gut microbiota on brain and behavior has the potential to inform novel management strategies for stress-related gastrointestinal and neuropsychiatric disorders. PMID:26912607

Identification of a Peripheral Nerve Neurite Growth-Promoting Activity by Development and Use of an in vitro Bioassay

NASA Astrophysics Data System (ADS)

Sandrock, Alfred W.; Matthew, William D.

1987-10-01

The effective regeneration of severed neuronal axons in the peripheral nerves of adult mammals may be explained by the presence of molecules in situ that promote the effective elongation of neurites. The absence of such molecules in the central nervous system of these animals may underlie the relative inability of axons to regenerate in this tissue after injury. In an effort to identify neurite growth-promoting molecules in tissues that support effective axonal regeneration, we have developed an in vitro bioassay that is sensitive to substrate-bound factors of peripheral nerve that influence the growth of neurites. In this assay, neonatal rat superior cervical ganglion explants are placed on longitudinal cryostat sections of fresh-frozen sciatic nerve, and the regrowing axons are visualized by catecholamine histofluorescence. Axons are found to regenerate effectively over sciatic nerve tissue sections. When ganglia are similarly explanted onto cryostat sections of adult rat central nervous system tissue, however, axonal regeneration is virtually absent. We have begun to identify the molecules in peripheral nerve that promote effective axonal regeneration by examining the effect of antibodies that interfere with the activity of previously described neurite growth-promoting factors. Axonal elongation over sciatic nerve tissue was found to be sensitive to the inhibitory effects of INO (for inhibitor of neurite outgrowth), a monoclonal antibody that recognizes and inhibits a neurite growth-promoting activity from PC-12 cell-conditioned medium. The INO antigen appears to be a molecular complex of laminin and heparan sulfate proteoglycan. In contrast, a rabbit antiserum that recognizes laminin purified from mouse Engelbreth-Holm-Swarm (EHS) sarcoma, stains the Schwann cell basal lamina of peripheral nerve, and inhibits neurite growth over purified laminin substrata has no detectable effect on the rate of axonal regeneration in our assay.

What have we learned about GPER function in physiology and disease from knockout mice?

PubMed

Prossnitz, Eric R; Hathaway, Helen J

2015-09-01

Estrogens, predominantly 17β-estradiol, exert diverse effects throughout the body in both normal and pathophysiology, during development and in reproductive, metabolic, endocrine, cardiovascular, nervous, musculoskeletal and immune systems. Estrogen and its receptors also play important roles in carcinogenesis and therapy, particularly for breast cancer. In addition to the classical nuclear estrogen receptors (ERα and ERβ) that traditionally mediate predominantly genomic signaling, the G protein-coupled estrogen receptor GPER has become recognized as a critical mediator of rapid signaling in response to estrogen. Mouse models, and in particular knockout (KO) mice, represent an important approach to understand the functions of receptors in normal physiology and disease. Whereas ERα KO mice display multiple significant defects in reproduction and mammary gland development, ERβ KO phenotypes are more limited, and GPER KO exhibit no reproductive deficits. However, the study of GPER KO mice over the last six years has revealed that GPER deficiency results in multiple physiological alterations including obesity, cardiovascular dysfunction, insulin resistance and glucose intolerance. In addition, the lack of estrogen-mediated effects in numerous tissues of GPER KO mice, studied in vivo or ex vivo, including those of the cardiovascular, endocrine, nervous and immune systems, reveals GPER as a genuine mediator of estrogen action. Importantly, GPER KO mice have also demonstrated roles for GPER in breast carcinogenesis and metastasis. In combination with the supporting effects of GPER-selective ligands and GPER knockdown approaches, GPER KO mice demonstrate the therapeutic potential of targeting GPER activity in diseases as diverse as obesity, diabetes, multiple sclerosis, hypertension, atherosclerosis, myocardial infarction, stroke and cancer. Copyright © 2015. Published by Elsevier Ltd.

Toxicogenomic profiling in maternal and fetal rodent brains following gestational exposure to chlorpyrifos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moreira, Estefania G.; Department of Physiological Sciences, State University of Londrina, Londrina, PR; Yu Xiaozhong

2010-06-15

Considering the wide variety of effects that have been reported to occur in the developmental neurotoxicity of chlorpyrifos (CP) and the lack of consensus on their dependence of brain acetylcholinesterase (AChE) activity inhibition, we applied microarray technology to explore dose-dependent alterations in transcriptional response in the fetal and maternal C57BL/6 mouse brain after daily gestational exposure (days 6 to 17) to CP (2, 4, 10, 12 or 15 mg/kg, sc). We identified significantly altered genes across doses and assessed for overrepresentation of Gene Ontology (GO) biological processes and KEGG pathways. We further clustered genes based on their expression profiles acrossmore » doses and repeated the GO/pathways analysis for each cluster. The dose-effect relationship of CP on gene expression, both at the gene and pathway levels was non-monotonic and not necessarily related to brain AChE inhibition. The largest impact was observed in the 10 mg/kg dose group which was also the LOAEL for brain AChE inhibition. In the maternal brain, lower doses (4 mg/kg) influenced GO categories and pathways such as cell adhesion, behavior, lipid metabolism, long-term potentiation, nervous system development, neurogenesis, synaptic transmission. In the fetal brain, lower doses (2 and/or 4 mg/kg) significantly altered cell division, translation, transmission of nerve impulse, chromatin modification, long-term potentiation. In addition, some genes involved in nervous system development and signaling were shown to be specifically influenced by these lower CP doses. Our approach was sensitive and reflected the diversity of responses known to be disrupted by CP and highlighted possible additional consequences of CP neurotoxicity, such as disturbance of the ubiquitin proteasome system.« less

NEURONAL ACTION ON THE DEVELOPING BLOOD VESSEL PATTERN

PubMed Central

James, Jennifer M.; Mukouyama, Yoh-suke

2011-01-01

The nervous system relies on a highly specialized network of blood vessels for development and neuronal survival. Recent evidence suggests that both the central and peripheral nervous systems (CNS and PNS) employ multiple mechanisms to shape the vascular tree to meet its specific metabolic demands, such as promoting nerve-artery alignment in the PNS or the development the blood brain barrier in the CNS. In this article we discuss how the nervous system directly influences blood vessel patterning resulting in neuro-vascular congruence that is maintained throughout development and in the adult. PMID:21978864

Nervous system development in lecithotrophic larval and juvenile stages of the annelid Capitella teleta.

PubMed

Meyer, Néva P; Carrillo-Baltodano, Allan; Moore, Richard E; Seaver, Elaine C

2015-01-01

Reconstructing the evolutionary history of nervous systems requires an understanding of their architecture and development across diverse taxa. The spiralians encompass diverse body plans and organ systems, and within the spiralians, annelids exhibit a variety of morphologies, life histories, feeding modes and associated nervous systems, making them an ideal group for studying evolution of nervous systems. We describe nervous system development in the annelid Capitella teleta (Blake JA, Grassle JP, Eckelbarger KJ. Capitella teleta, a new species designation for the opportunistic and experimental Capitella sp. I, with a review of the literature for confirmed records. Zoosymposia. 2009;2:25-53) using whole-mount in situ hybridization for a synaptotagmin 1 homolog, nuclear stains, and cross-reactive antibodies against acetylated α-tubulin, 5-HT and FMRFamide. Capitella teleta is member of the Sedentaria (Struck TH, Paul C, Hill N, Hartmann S, Hosel C, Kube M, et al. Phylogenomic analyses unravel annelid evolution. Nature. 2011;471:95-8) and has an indirectly-developing, lecithotrophic larva. The nervous system of C. teleta shares many features with other annelids, including a brain and a ladder-like ventral nerve cord with five connectives, reiterated commissures, and pairs of peripheral nerves. Development of the nervous system begins with the first neurons differentiating in the brain, and follows a temporal order from central to peripheral and from anterior to posterior. Similar to other annelids, neurons with serotonin-like-immunoreactivity (5HT-LIR) and FMRFamide-like-immunoreactivity (FMRF-LIR) are found throughout the brain and ventral nerve cord. A small number of larval-specific neurons and neurites are present, but are visible only after the central nervous system begins to form. These larval neurons are not visible after metamorphosis while the rest of the nervous system is largely unchanged in juveniles. Most of the nervous system that forms during larvogenesis in C. teleta persists into the juvenile stage. The first neurons differentiate in the brain, which contrasts with the early formation of peripheral, larval-specific neurons found in some spiralian taxa with planktotrophic larvae. Our study provides a clear indication that certain shared features among annelids - e.g., five connectives in the ventral nerve cord - are only visible during larval stages in particular species, emphasizing the need to include developmental data in ancestral character state reconstructions. The data provided in this paper will serve as an important comparative reference for understanding evolution of nervous systems, and as a framework for future molecular studies of development.

Effect of New Antiviral Agent Camphecin on Behavior of Mice.

PubMed

Babina, A V; Lavrinenko, V A; Yarovaya, O I; Salakhutdinov, N F

2017-01-01

We studied the effect of camphecin (1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene-aminoethanol) on mouse behavior in the open-field test. Camphecin possesses antiviral activity and inhibits viral replication, but its influence on the nervous system is poorly studied. Single camphecin injection produced no significant changes in behavioral patterns. Chronic camphecin administration (5 times over 2 weeks) to mice of different strains had no significant influence on open field behavior (motor, exploratory activity, anxiety, emotional state and vegetative functions). The findings are discussed in the context of neutral influence of camphecin on animal behavior.

Correlations Decrease with Propagation of Spiking Activity in the Mouse Barrel Cortex

PubMed Central

Ranganathan, Gayathri Nattar; Koester, Helmut Joachim

2011-01-01

Propagation of suprathreshold spiking activity through neuronal populations is important for the function of the central nervous system. Neural correlations have an impact on cortical function particularly on the signaling of information and propagation of spiking activity. Therefore we measured the change in correlations as suprathreshold spiking activity propagated between recurrent neuronal networks of the mammalian cerebral cortex. Using optical methods we recorded spiking activity from large samples of neurons from two neural populations simultaneously. The results indicate that correlations decreased as spiking activity propagated from layer 4 to layer 2/3 in the rodent barrel cortex. PMID:21629764

Intermittent hypoxia promotes recovery of respiratory motor function in spinal cord-injured mice depleted of serotonin in the central nervous system.

PubMed

Komnenov, Dragana; Solarewicz, Julia Z; Afzal, Fareeza; Nantwi, Kwaku D; Kuhn, Donald M; Mateika, Jason H

2016-08-01

We examined the effect of repeated daily exposure to intermittent hypoxia (IH) on the recovery of respiratory and limb motor function in mice genetically depleted of central nervous system serotonin. Electroencephalography, diaphragm activity, ventilation, core body temperature, and limb mobility were measured in spontaneously breathing wild-type (Tph2(+/+)) and tryptophan hydroxylase 2 knockout (Tph2(-/-)) mice. Following a C2 hemisection, the mice were exposed daily to IH (i.e., twelve 4-min episodes of 10% oxygen interspersed with 4-min normoxic periods followed by a 90-min end-recovery period) or normoxia (i.e., sham protocol, 21% oxygen) for 10 consecutive days. Diaphragm activity recovered to prehemisection levels in the Tph2(+/+) and Tph2(-/-) mice following exposure to IH but not normoxia [Tph2(+/+) 1.3 ± 0.2 (SE) vs. 0.3 ± 0.2; Tph2(-/-) 1.06 ± 0.1 vs. 0.3 ± 0.1, standardized to prehemisection values, P < 0.01]. Likewise, recovery of tidal volume and breathing frequency was evident, although breathing frequency values did not return to prehemisection levels within the time frame of the protocol. Partial recovery of limb motor function was also evident 2 wk after spinal cord hemisection. However, recovery was not dependent on IH or the presence of serotonin in the central nervous system. We conclude that IH promotes recovery of respiratory function but not basic motor tasks. Moreover, we conclude that spontaneous or treatment-induced recovery of respiratory and motor limb function is not dependent on serotonin in the central nervous system in a mouse model of spinal cord injury.

Real-time PCR quantification of gene expression in embryonic mouse tissue.

PubMed

Villalon, Eric; Schulz, David J; Waters, Samuel T

2014-01-01

The Gbx family of transcription factors consists of two closely related proteins GBX1 and GBX2. A defining feature of the GBX family is a highly conserved 60 amino acid DNA-binding domain, which differs by just two amino acids. Gbx1 and Gbx2 are co-expressed in several areas of the developing central nervous system including the forebrain, anterior hindbrain, and spinal cord, suggesting the potential for genetic redundancy. However, there is a spatiotemporal difference in expression of Gbx1 and Gbx2 in the forebrain and spinal cord. Gbx2 has been shown to play a critical role in positioning the midbrain/hindbrain boundary and developing anterior hindbrain, whereas gene-targeting experiments in mice have revealed an essential function for Gbx1 in the spinal cord for normal locomotion. To determine if Gbx2 could potentially compensate for a loss of Gbx1 in the developing spinal cord, we performed real-time PCR to examine levels of Gbx2 expression in Gbx1(-/-) spinal cord at embryonic day (E) 13.5, a developmental stage when Gbx2 is rapidly downregulated. We demonstrate that Gbx2 expression is elevated in the spinal cord of Gbx1(-/-) embryos.

Different modes of herpes simplex virus type 1 spread in brain and skin tissues.

PubMed

Tsalenchuck, Yael; Tzur, Tomer; Steiner, Israel; Panet, Amos

2014-02-01

Herpes simplex virus type 1 (HSV-1) initially infects the skin and subsequently spreads to the nervous system. To investigate and compare HSV-1 mode of propagation in the two clinically relevant tissues, we have established ex vivo infection models, using native tissues of mouse and human skin, as well as mouse brain, maintained in organ cultures. HSV-1, which is naturally restricted to the human, infects and spreads in the mouse and human skin tissues in a similar fashion, thus validating the mouse model. The spread of HSV-1 in the skin was concentric to form typical plaques of limited size, predominantly of cytopathic cells. By contrast, HSV-1 spread in the brain tissue was directed along specific neuronal networks with no apparent cytopathic effect. Two additional differences were noted following infection of the skin and brain tissues. First, only a negligible amount of extracellular progeny virus was produced of the infected brain tissues, while substantial quantity of infectious progeny virus was released to the media of the infected skin. Second, antibodies against HSV-1, added following the infection, effectively restricted viral spread in the skin but have no effect on viral spread in the brain tissue. Taken together, these results reveal that HSV-1 spread within the brain tissue mostly by direct transfer from cell to cell, while in the skin the progeny extracellular virus predominates, thus facilitating the infection to new individuals.

In-depth behavioral characterization of the corticosterone mouse model and the critical involvement of housing conditions.

PubMed

Demuyser, Thomas; Deneyer, Lauren; Bentea, Eduard; Albertini, Giulia; Van Liefferinge, Joeri; Merckx, Ellen; De Prins, An; De Bundel, Dimitri; Massie, Ann; Smolders, Ilse

2016-03-15

Depression and anxiety are disabling and highly prevalent psychiatric disorders. To better understand the neurobiological basis of mood and anxiety disorders, relevant animal models are needed. The corticosterone mouse model is frequently used to study depression. Chronic stress and accompanying glucocorticoid elevation causes pathological changes in the central nervous system, which are related to psychiatric symptoms. Exogenous administration of corticosterone is therefore often used to induce depressive-like behavior in mice and in some cases also features of anxiety-like behavior are shown. However, a thorough characterization of this model has never been conducted and housing conditions of the used subjects often differ between the implemented protocols. We chronically administered a subcutaneous corticosterone bolus injection to single- and group-housed mice, and we subsequently evaluated the face validity of this model by performing a battery of behavioral tests (forced swim test, mouse-tail suspension test, saccharin intake test, novelty-suppressed feeding test, elevated plus maze, light/dark paradigm and open field test). Our results show that corticosterone treatment has a substantial overall effect on depressive-like behavior. Increases in anxiety-like behavior on the other hand are mainly seen in single housed animals, independent of treatment. The current study therefore does not only show a detailed behavioral characterization of the corticosterone mouse model, but furthermore also elucidates the critical influence of housing conditions on the behavioral outcome in this model. Copyright © 2015 Elsevier Inc. All rights reserved.

Regional differences in the expression of laminin isoforms during mouse neural tube development

PubMed Central

Copp, Andrew J.; Carvalho, Rita; Wallace, Adam; Sorokin, Lydia; Sasaki, Takako; Greene, Nicholas D.E.; Ybot-Gonzalez, Patricia

2013-01-01

Many significant human birth defects originate around the time of neural tube closure or early during post-closure nervous system development. For example, failure of the neural tube to close generates anencephaly and spina bifida, faulty cell cycle progression is implicated in primary microcephaly, while defective migration of neuroblasts can lead to neuronal migration disorders such as lissencephaly. At the stage of neural tube closure, basement membranes are becoming organised around the neuroepithelium, and beneath the adjacent non-neural surface ectoderm. While there is circumstantial evidence to implicate basement membrane dynamics in neural tube and surface ectodermal development, we have an incomplete understanding of the molecular composition of basement membranes at this stage. In the present study, we examined the developing basement membranes of the mouse embryo at mid-gestation (embryonic day 9.5), with particular reference to laminin composition. We performed in situ hybridization to detect the mRNAs of all eleven individual laminin chains, and immunohistochemistry to identify which laminin chains are present in the basement membranes. From this information, we inferred the likely laminin variants and their tissues of origin: that is, whether a given basement membrane laminin is contributed by epithelium, mesenchyme, or both. Our findings reveal major differences in basement composition along the body axis, with the rostral neural tube (at mandibular arch and heart levels) exhibiting many distinct laminin variants, while the lumbar level where the neural tube is just closing shows a much simpler laminin profile. Moreover, there appears to be a marked difference in the extent to which the mesenchyme contributes laminin variants to the basement membrane, with potential contribution of several laminins rostrally, but no contribution caudally. This information paves the way towards a mechanistic analysis of basement membrane laminin function during early neural tube development in mammals. PMID:21524702

Activity-Based Protein Profiling of Organophosphorus and Thiocarbamate Pesticides Reveals Multiple Serine Hydrolase Targets in Mouse Brain

PubMed Central

NOMURA, DANIEL K.; CASIDA, JOHN E.

2010-01-01

Organophosphorus (OP) and thiocarbamate (TC) agrochemicals are used worldwide as insecticides, herbicides, and fungicides, but their safety assessment in terms of potential off-targets remains incomplete. In this study, we used a chemoproteomic platform, termed activity-based protein profiling, to broadly define serine hydrolase targets in mouse brain of a panel of 29 OP and TC pesticides. Among the secondary targets identified, enzymes involved in degradation of endocannabinoid signaling lipids, monoacylglycerol lipase and fatty acid amide hydrolase, were inhibited by several OP and TC pesticides. Blockade of these two enzymes led to elevations in brain endocannabinoid levels and dysregulated brain arachidonate metabolism. Other secondary targets include enzymes thought to also play important roles in the nervous system and unannotated proteins. This study reveals a multitude of secondary targets for OP and TC pesticides and underscores the utility of chemoproteomic platforms in gaining insights into biochemical pathways that are perturbed by these toxicants. PMID:21341672

AUTONOMIC AXONS IN THE HUMAN ENDOCRINE PANCREAS SHOW UNIQUE INNERVATION PATTERNS

PubMed Central

Rodriguez-Diaz, Rayner; Abdulreda, Midhat H.; Formoso, Alexander L.; Gans, Itai; Ricordi, Camillo; Berggren, Per-Olof; Caicedo, Alejandro

2011-01-01

SUMMARY The autonomic nervous system regulates hormone secretion from the endocrine pancreas, the islets of Langerhans, and thus impacts glucose metabolism. The parasympathetic and sympathetic nerves innervate the pancreatic islet, but the precise innervation patterns are not known, particularly in human islets. Here we demonstrate that the innervation of human islets is different from that of mouse islets and that it does not conform to existing models of autonomic control of islet function. By visualizing axons in three dimensions and quantifying axonal densities and contacts within pancreatic islets, we found that, in contrast to mouse endocrine cells, human endocrine cells are sparsely contacted by autonomic axons. Few parasympathetic cholinergic axons penetrate the human islet and the invading sympathetic fibers preferentially innervate smooth muscle cells of blood vessels located within the islet. Thus, rather than modulating endocrine cell function directly, sympathetic nerves may regulate hormone secretion in human islets by controlling local blood flow or by acting on islet regions located downstream. PMID:21723503

Modular control of glutamatergic neuronal identity in C.elegans by distinct homeodomain proteins

PubMed Central

Serrano-Saiz, Esther; Poole, Richard J.; Felton, Terry; Zhang, Feifan; De La Cruz, Estanisla Daniel; Hobert, Oliver

2013-01-01

The choice of using one of many possible neurotransmitter systems is a critical step in defining the identity of an individual neuron type. We show here that the key defining feature of glutamatergic neurons, the vesicular glutamate transporter EAT-4/VGLUT is expressed in 38 of the 118 anatomically defined neuron classes of the C.elegans nervous system. We show that eat-4/VGLUT expression is controlled in a modular manner, with distinct cis-regulatory modules driving expression in distinct glutamatergic neuron classes. We identify 13 different transcription factors, 11 of them homeodomain proteins, that act in specific combinations in 25 different glutamatergic neuron classes to initiate and maintain eat-4/VGLUT expression. We show that the adoption of a glutamatergic phenotype is linked to the adoption of other terminal identity features of a neuron, including cotransmitter phenotypes. Examination of mouse orthologs of these homeodomain proteins resulted in the identification of mouse LHX1 as a regulator of glutamatergic neurons in the brainstem. PMID:24243022

The mouse F3/contactin glycoprotein

PubMed Central

Bizzoca, Antonella; Corsi, Patrizia

2009-01-01

F3/Contactin is an immunoglobulin superfamily component expressed in the nervous tissue of several species. Here we focus on the structural and functional properties of its mouse relative, on the mechanisms driving its regulated expression and on its developmental role. F3/Contactin is differentially expressed in distinct populations of central and peripheral neurons and in some non-neuronal cells. Accordingly, the regulatory region of the underlying gene includes promoter elements undergoing differential activation, associated with an intricate splicing profile, indicating that transcriptional and posttranscriptional mechanisms contribute to its expression. Transgenic models allowed to follow F3/Contactin promoter activation in vivo and to modify F3/Contactin gene expression under a heterologous promoter, which resulted in morphological and functional phenotypes. Besides axonal growth and pathfinding, these concerned earlier events, including precursor proliferation and commitment. This wide role in neural ontogenesis is consistent with the recognized interaction of F3/Contactin with developmental control genes belonging to the Notch pathway. PMID:19372728

Insulin-like growth factor I/somatomedin C: a potent inducer of oligodendrocyte development

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMorris, F.A.; Smith, T.M.; DeSalvo, S.

1986-02-01

Cell cultures established from cerebrum of 1-day-old rats were used to investigate hormonal regulation of the development of oligodendrocytes, which synthesize myelin in the central nervous system. The number of oligodendrocytes that developed was preferentially increased by insulin, or by insulin-like growth factor I (IGF-I), also known as somatomedin C. High concentrations of insulin were required for substantial induction of oligodendrocyte development, whereas only 3.3 ng of IGF-I per ml was needed for a 2-fold increase in oligodendrocyte numbers. At an IGF-I concentration of 100 ng/ml, oligodendrocyte numbers were increased 6-fold in cultures grown in the presence of 10% fetalmore » bovine serum, or up to 60-fold in cultures maintained in serum-free medium. IGF-I produced less than a 2-fold increase in the number of nonoligodendroglial cells in the same cultures. Type I IGF receptors were identified on oligodendrocytes and on a putative oligodendrocyte precursor cell population identified by using mouse monoclonal antibody A2B5. Radioligand binding assays were done. These results indicate that IGF-I is a potent inducer of oligodendrocyte development and suggest a possible mechanism based on IGF deficiency for the hypomyelination that results from early postnatal malnutrition.« less

Loss of the E3 ubiquitin ligase LRSAM1 sensitizes peripheral axons to degeneration in a mouse model of Charcot-Marie-Tooth disease.

PubMed

Bogdanik, Laurent P; Sleigh, James N; Tian, Cong; Samuels, Mark E; Bedard, Karen; Seburn, Kevin L; Burgess, Robert W

2013-05-01

Charcot-Marie-Tooth disease (CMT) is a clinically and genetically heterogeneous condition characterized by peripheral axon degeneration with subsequent motor and sensory deficits. Several CMT gene products function in endosomal sorting and trafficking to the lysosome, suggesting that defects in this cellular pathway might present a common pathogenic mechanism for these conditions. LRSAM1 is an E3 ubiquitin ligase that is implicated in this process, and mutations in LRSAM1 have recently been shown to cause CMT. We have generated mouse mutations in Lrsam1 to create an animal model of this form of CMT (CMT2P). Mouse Lrsam1 is abundantly expressed in the motor and sensory neurons of the peripheral nervous system. Both homozygous and heterozygous mice have largely normal neuromuscular performance and only a very mild neuropathy phenotype with age. However, Lrsam1 mutant mice are more sensitive to challenge with acrylamide, a neurotoxic agent that causes axon degeneration, indicating that the axons in the mutant mice are indeed compromised. In transfected cells, LRSAM1 primarily localizes in a perinuclear compartment immediately beyond the Golgi and shows little colocalization with components of the endosome to lysosome trafficking pathway, suggesting that other cellular mechanisms also merit consideration.

Targeting human Mas-related G protein-coupled receptor X1 to inhibit persistent pain

PubMed Central

Li, Zhe; Tseng, Pang-Yen; Tiwari, Vinod; Xu, Qian; He, Shao-Qiu; Wang, Yan; Zheng, Qin; Han, Liang; Wu, Zhiping; Blobaum, Anna L.; Cui, Yiyuan; Tiwari, Vineeta; Sun, Shuohao; Cheng, Yingying; Huang-Lionnet, Julie H. Y.; Geng, Yixun; Xiao, Bo; Peng, Junmin; Hopkins, Corey; Raja, Srinivasa N.; Guan, Yun; Dong, Xinzhong

2017-01-01

Human Mas-related G protein-coupled receptor X1 (MRGPRX1) is a promising target for pain inhibition, mainly because of its restricted expression in nociceptors within the peripheral nervous system. However, constrained by species differences across Mrgprs, drug candidates that activate MRGPRX1 do not activate rodent receptors, leaving no responsive animal model to test the effect on pain in vivo. Here, we generated a transgenic mouse line in which we replaced mouse Mrgprs with human MrgprX1. This humanized mouse allowed us to characterize an agonist [bovine adrenal medulla 8–22 (BAM8–22)] and a positive allosteric modulator (PAM), ML382, of MRGPRX1. Cellular studies suggested that ML382 enhances the ability of BAM8–22 to inhibit high-voltage-activated Ca2+ channels and attenuate spinal nociceptive transmission. Importantly, both BAM8–22 and ML382 effectively attenuated evoked, persistent, and spontaneous pain without causing obvious side effects. Notably, ML382 by itself attenuated both evoked pain hypersensitivity and spontaneous pain in MrgprX1 mice after nerve injury without acquiring coadministration of an exogenous agonist. Our findings suggest that humanized MrgprX1 mice provide a promising preclinical model and that activating MRGPRX1 is an effective way to treat persistent pain. PMID:28223516

The androgen receptor governs the execution, but not programming, of male sexual and territorial behaviors

PubMed Central

Juntti, Scott A; Tollkuhn, Jessica; Wu, Melody V; Fraser, Eleanor J; Soderborg, Taylor; Tan, Stella; Honda, Shin-Ichiro; Harada, Nobuhiro; Shah, Nirao M

2010-01-01

SUMMARY Testosterone and estrogen are essential for male behaviors in vertebrates. How these two signaling pathways interact to control masculinization of the brain and behavior remains to be established. Circulating testosterone activates the androgen receptor (AR) and also serves as the source of estrogen in the brain. We have used a genetic strategy to delete AR specifically in the mouse nervous system. This approach permits us to determine the function of AR in sexually dimorphic behaviors in males while maintaining circulating testosterone levels within the normal range. We find that AR mutant males exhibit masculine sexual and territorial displays, but they have striking deficits in specific components of these behaviors. Taken together with the surprisingly limited expression of AR in the developing brain, our findings indicate that testosterone acts as a precursor to estrogen to masculinize the brain and behavior, and signals via AR to control the levels of male behavioral displays. PMID:20435002

Validation of long-term primary neuronal cultures and network activity through the integration of reversibly bonded microbioreactors and MEA substrates.

PubMed

Biffi, Emilia; Menegon, Andrea; Piraino, Francesco; Pedrocchi, Alessandra; Fiore, Gianfranco B; Rasponi, Marco

2012-01-01

In vitro recording of neuronal electrical activity is a widely used technique to understand brain functions and to study the effect of drugs on the central nervous system. The integration of microfluidic devices with microelectrode arrays (MEAs) enables the recording of networks activity in a controlled microenvironment. In this work, an integrated microfluidic system for neuronal cultures was developed, reversibly coupling a PDMS microfluidic device with a commercial flat MEA through magnetic forces. Neurons from mouse embryos were cultured in a 100 µm channel and their activity was followed up to 18 days in vitro. The maturation of the networks and their morphological and functional characteristics were comparable with those of networks cultured in macro-environments and described in literature. In this work, we successfully demonstrated the ability of long-term culturing of primary neuronal cells in a reversible bonded microfluidic device (based on magnetism) that will be fundamental for neuropharmacological studies. Copyright © 2011 Wiley Periodicals, Inc.

Proliferative reactive gliosis is compatible with glial metabolic support and neuronal function

PubMed Central

2011-01-01

Background The response of mammalian glial cells to chronic degeneration and trauma is hypothesized to be incompatible with support of neuronal function in the central nervous system (CNS) and retina. To test this hypothesis, we developed an inducible model of proliferative reactive gliosis in the absence of degenerative stimuli by genetically inactivating the cyclin-dependent kinase inhibitor p27Kip1 (p27 or Cdkn1b) in the adult mouse and determined the outcome on retinal structure and function. Results p27-deficient Müller glia reentered the cell cycle, underwent aberrant migration, and enhanced their expression of intermediate filament proteins, all of which are characteristics of Müller glia in a reactive state. Surprisingly, neuroglial interactions, retinal electrophysiology, and visual acuity were normal. Conclusion The benign outcome of proliferative reactive Müller gliosis suggests that reactive glia display context-dependent, graded and dynamic phenotypes and that reactivity in itself is not necessarily detrimental to neuronal function. PMID:21985191

Inhibition of isoleucyl-tRNA synthetase as a potential treatment for human African Trypanosomiasis.

PubMed

Cestari, Igor; Stuart, Kenneth

2013-05-17

Trypanosoma brucei sp. causes human African trypanosomiasis (HAT; African sleeping sickness). The parasites initially proliferate in the hemolymphatic system and then invade the central nervous system, which is lethal if not treated. New drugs are needed for HAT because the approved drugs are few, toxic, and difficult to administer, and drug resistance is spreading. We showed by RNAi knockdown that T. brucei isoleucyl-tRNA synthetase is essential for the parasites in vitro and in vivo in a mouse model of infection. By structure prediction and experimental analysis, we also identified small molecules that inhibit recombinant isoleucyl-tRNA synthetase and that are lethal to the parasites in vitro and highly selective compared with mammalian cells. One of these molecules acts as a competitive inhibitor of the enzyme and cures mice of the infection. Because members of this class of molecules are known to cross the blood-brain barrier in humans and to be tolerated, they may be attractive as leading candidates for drug development for HAT.

Inhibition of Isoleucyl-tRNA Synthetase as a Potential Treatment for Human African Trypanosomiasis*

PubMed Central

Cestari, Igor; Stuart, Kenneth

2013-01-01

Trypanosoma brucei sp. causes human African trypanosomiasis (HAT; African sleeping sickness). The parasites initially proliferate in the hemolymphatic system and then invade the central nervous system, which is lethal if not treated. New drugs are needed for HAT because the approved drugs are few, toxic, and difficult to administer, and drug resistance is spreading. We showed by RNAi knockdown that T. brucei isoleucyl-tRNA synthetase is essential for the parasites in vitro and in vivo in a mouse model of infection. By structure prediction and experimental analysis, we also identified small molecules that inhibit recombinant isoleucyl-tRNA synthetase and that are lethal to the parasites in vitro and highly selective compared with mammalian cells. One of these molecules acts as a competitive inhibitor of the enzyme and cures mice of the infection. Because members of this class of molecules are known to cross the blood-brain barrier in humans and to be tolerated, they may be attractive as leading candidates for drug development for HAT. PMID:23548908

Survival of adult neurons lacking cholesterol synthesis in vivo

PubMed Central

Fünfschilling, Ursula; Saher, Gesine; Xiao, Le; Möbius, Wiebke; Nave, Klaus-Armin

2007-01-01

Background Cholesterol, an essential component of all mammalian plasma membranes, is highly enriched in the brain. Both during development and in the adult, brain cholesterol is derived from local cholesterol synthesis and not taken up from the circulation. However, the contribution of neurons and glial cells to total brain cholesterol metabolism is unknown. Results Using conditional gene inactivation in the mouse, we disrupted the squalene synthase gene (fdft1), which is critical for cholesterol synthesis, in cerebellar granule cells and some precerebellar nuclei. Mutant mice showed no histological signs of neuronal degeneration, displayed ultrastructurally normal synapses, and exhibited normal motor coordination. This revealed that these adult neurons do not require cell-autonomous cholesterol synthesis for survival or function. Conclusion We conclude that at least some adult neurons no longer require endogenous cholesterol synthesis and can fully meet their cholesterol needs by uptake from their surrounding. Glia are a likely source of cholesterol in the central nervous system. PMID:17199885

Sonic hedgehog signaling regulates actin cytoskeleton via Tiam1-Rac1 cascade during spine formation.

PubMed

Sasaki, Nobunari; Kurisu, Junko; Kengaku, Mineko

2010-12-01

The sonic hedgehog (Shh) pathway has essential roles in several processes during development of the vertebrate central nervous system (CNS). Here, we report that Shh regulates dendritic spine formation in hippocampal pyramidal neurons via a novel pathway that directly regulates the actin cytoskeleton. Shh signaling molecules Patched (Ptc) and Smoothened (Smo) are expressed in several types of postmitotic neurons, including cerebellar Purkinje cells and hippocampal pyramidal neurons. Knockdown of Smo induces dendritic spine formation in cultured hippocampal neurons independently of Gli-mediated transcriptional activity. Smo interacts with Tiam1, a guanine nucleotide exchange factor for Rac1, via its cytoplasmic C-terminal region. Inhibition of Tiam1 or Rac1 activity suppresses spine induction by Smo knockdown. Shh induces remodeling of the actin cytoskeleton independently of transcriptional activation in mouse embryonic fibroblasts. These findings demonstrate a novel Shh pathway that regulates the actin cytoskeleton via Tiam1-Rac1 activation. Copyright © 2010 Elsevier Inc. All rights reserved.

TAM receptors regulate multiple features of microglial physiology.

PubMed

Fourgeaud, Lawrence; Través, Paqui G; Tufail, Yusuf; Leal-Bailey, Humberto; Lew, Erin D; Burrola, Patrick G; Callaway, Perri; Zagórska, Anna; Rothlin, Carla V; Nimmerjahn, Axel; Lemke, Greg

2016-04-14

Microglia are damage sensors for the central nervous system (CNS), and the phagocytes responsible for routine non-inflammatory clearance of dead brain cells. Here we show that the TAM receptor tyrosine kinases Mer and Axl regulate these microglial functions. We find that adult mice deficient in microglial Mer and Axl exhibit a marked accumulation of apoptotic cells specifically in neurogenic regions of the CNS, and that microglial phagocytosis of the apoptotic cells generated during adult neurogenesis is normally driven by both TAM receptor ligands Gas6 and protein S. Using live two-photon imaging, we demonstrate that the microglial response to brain damage is also TAM-regulated, as TAM-deficient microglia display reduced process motility and delayed convergence to sites of injury. Finally, we show that microglial expression of Axl is prominently upregulated in the inflammatory environment that develops in a mouse model of Parkinson's disease. Together, these results establish TAM receptors as both controllers of microglial physiology and potential targets for therapeutic intervention in CNS disease.

Immunocytochemical methods to study the distribution of Orientia tsutsugamushi in Leptotrombidium (Acari: Trombiculidae) chiggers.

PubMed

Myint, K S; Linthicum, K J; Tanskul, P; Lerdthusnee, K; Vaughn, D W; Manomuth, C; Mongkolsirichaikul, D; Hansukjariya, P; Hastriter, M W

1998-07-01

Immunocytochemical methods were developed and tested for their ability to detect the distribution of Orientia tsutsugamushi in paraffin sections of adult chiggers (Leptotrombidium imphalum Vercammen-Grandjean & Langston). Rickettsial antigen was detected by application of a simple direct or amplified immunocytochemistry procedure and an indirect immunofluorescent procedure. In the direct procedure alkaline phosphatase conjugation to the mouse polyclonal antibody to the Karp strain was followed by the HistoMark Red test system to detect rickettsial antigen. The amplification procedure used a similar method but used an unlabeled primary antibody followed by secondary biotinylated antimouse IgG, streptavidin-alkaline phosphatase, and the HistoMark Red test system. The immunofluorescent procedure included a biotinylated secondary antibody followed by addition of a streptavidin-FITC conjugate. Specific tissue tropisms in infected chiggers were observed in the salivary glands, nervous tissue, and ovaries of adult female mites in all procedures; however, nonspecific fluorescence of the chigger limited definitive identification of tissue tropisms with the indirect immunofluorescent procedure.

Cre-dependent selection yields AAV variants for widespread gene transfer to the adult brain

PubMed Central

Deverman, Benjamin E.; Pravdo, Piers L.; Simpson, Bryan P.; Kumar, Sripriya Ravindra; Chan, Ken Y.; Banerjee, Abhik; Wu, Wei-Li; Yang, Bin; Huber, Nina; Pasca, Sergiu P.; Gradinaru, Viviana

2015-01-01

Recombinant adeno-associated viruses (rAAVs) are commonly used vehicles for in vivo gene transfer1-6. However, the tropism repertoire of naturally occurring AAVs is limited, prompting a search for novel AAV capsids with desired characteristics7-13. Here we describe a capsid selection method, called Cre-recombination-based AAV targeted evolution (CREATE), that enables the development of AAV capsids that more efficiently transduce defined Cre-expressing cell populations in vivo. We use CREATE to generate AAV variants that efficiently and widely transduce the adult mouse central nervous system (CNS) after intravenous injection. One variant, AAV-PHP.B, transfers genes throughout the CNS with an efficiency that is at least 40-fold greater than that of the current standard, AAV914-17, and transduces the majority of astrocytes and neurons across multiple CNS regions. In vitro, it transduces human neurons and astrocytes more efficiently than does AAV9, demonstrating the potential of CREATE to produce customized AAV vectors for biomedical applications. PMID:26829320

Interleukin 35 and Hepatocyte Growth Factor; as a novel combined immune gene therapy for Multiple Sclerosis disease.

PubMed

Moghadam, Samira; Erfanmanesh, Maryam; Esmaeilzadeh, Abdolreza

2017-11-01

An autoimmune demyelination disease of the Central Nervous System, Multiple Sclerosis, is a chronic inflammation which mostly involves young adults. Suffering people face functional loss with a severe pain. Most current MS treatments are focused on the immune response suppression. Approved drugs suppress the inflammatory process, but factually, there is no definite cure for Multiple Sclerosis. Recently developed knowledge has demonstrated that gene and cell therapy as a hopeful approach in tissue regeneration. The authors propose a novel combined immune gene therapy for Multiple Sclerosis treatment using anti-inflammatory and remyelination of Interleukine-35 and Hepatocyte Growth Factor properties, respectively. In this hypothesis Interleukine-35 and Hepatocyte Growth Factor introduce to Mesenchymal Stem Cells of EAE mouse model via an adenovirus based vector. It is expected that Interleukine-35 and Hepatocyte Growth Factor genes expressed from MSCs could effectively perform in immunotherapy of Multiple Sclerosis. Copyright © 2017. Published by Elsevier Ltd.

Repression by PRDM13 is critical for generating precision in neuronal identity

PubMed Central

Kollipara, Rahul K; Ma, Zhenzhong; Borromeo, Mark D; Chang, Joshua C

2017-01-01

The mechanisms that activate some genes while silencing others are critical to ensure precision in lineage specification as multipotent progenitors become restricted in cell fate. During neurodevelopment, these mechanisms are required to generate the diversity of neuronal subtypes found in the nervous system. Here we report interactions between basic helix-loop-helix (bHLH) transcriptional activators and the transcriptional repressor PRDM13 that are critical for specifying dorsal spinal cord neurons. PRDM13 inhibits gene expression programs for excitatory neuronal lineages in the dorsal neural tube. Strikingly, PRDM13 also ensures a battery of ventral neural tube specification genes such as Olig1, Olig2 and Prdm12 are excluded dorsally. PRDM13 does this via recruitment to chromatin by multiple neural bHLH factors to restrict gene expression in specific neuronal lineages. Together these findings highlight the function of PRDM13 in repressing the activity of bHLH transcriptional activators that together are required to achieve precise neuronal specification during mouse development. PMID:28850031

Drosophila neuroglian: a member of the immunoglobulin superfamily with extensive homology to the vertebrate neural adhesion molecule L1.

PubMed

Bieber, A J; Snow, P M; Hortsch, M; Patel, N H; Jacobs, J R; Traquina, Z R; Schilling, J; Goodman, C S

1989-11-03

Drosophila neuroglian is an integral membrane glycoprotein that is expressed on a variety of cell types in the Drosophila embryo, including expression on a large subset of glial and neuronal cell bodies in the central and peripheral nervous systems and on the fasciculating axons that extend along them. Neuroglian cDNA clones were isolated by expression cloning. cDNA sequence analysis reveals that neuroglian is a member of the immunoglobulin superfamily. The extracellular portion of the protein consists of six immunoglobulin C2-type domains followed by five fibronectin type III domains. Neuroglian is closely related to the immunoglobulin-like vertebrate neural adhesion molecules and, among them, shows most extensive homology to mouse L1. Its homology to L1 and its embryonic localization suggest that neuroglian may play a role in neural and glial cell adhesion in the developing Drosophila embryo. We report here on the identification of a lethal mutation in the neuroglian gene.

Programmed cell death acts at different stages of Drosophila neurodevelopment to shape the central nervous system

PubMed Central

Desplan, Claude

2016-01-01

Nervous system development is a process that integrates cell proliferation, differentiation and programmed cell death (PCD). PCD is an evolutionary conserved mechanism and a fundamental developmental process by which the final cell number in a nervous system is established. In vertebrates and invertebrates, PCD can be determined intrinsically by cell lineage and age, as well as extrinsically by nutritional, metabolic and hormonal states. Drosophila has been an instrumental model for understanding how this mechanism is regulated. We review the role of PCD in Drosophila central nervous system development from neural progenitors to neurons, its molecular mechanism and function, how it is regulated and implemented, and how it ultimately shapes the fly central nervous system from the embryo to the adult. Finally, we discuss ideas that emerge while integrating this information. PMID:27404003

Targeting Human Central Nervous System Protein Kinases: An Isoform Selective p38αMAPK Inhibitor That Attenuates Disease Progression in Alzheimer’s Disease Mouse Models

PubMed Central

2015-01-01

The first kinase inhibitor drug approval in 2001 initiated a remarkable decade of tyrosine kinase inhibitor drugs for oncology indications, but a void exists for serine/threonine protein kinase inhibitor drugs and central nervous system indications. Stress kinases are of special interest in neurological and neuropsychiatric disorders due to their involvement in synaptic dysfunction and complex disease susceptibility. Clinical and preclinical evidence implicates the stress related kinase p38αMAPK as a potential neurotherapeutic target, but isoform selective p38αMAPK inhibitor candidates are lacking and the mixed kinase inhibitor drugs that are promising in peripheral tissue disease indications have limitations for neurologic indications. Therefore, pursuit of the neurotherapeutic hypothesis requires kinase isoform selective inhibitors with appropriate neuropharmacology features. Synaptic dysfunction disorders offer a potential for enhanced pharmacological efficacy due to stress-induced activation of p38αMAPK in both neurons and glia, the interacting cellular components of the synaptic pathophysiological axis, to be modulated. We report a novel isoform selective p38αMAPK inhibitor, MW01-18-150SRM (=MW150), that is efficacious in suppression of hippocampal-dependent associative and spatial memory deficits in two distinct synaptic dysfunction mouse models. A synthetic scheme for biocompatible product and positive outcomes from pharmacological screens are presented. The high-resolution crystallographic structure of the p38αMAPK/MW150 complex documents active site binding, reveals a potential low energy conformation of the bound inhibitor, and suggests a structural explanation for MW150’s exquisite target selectivity. As far as we are aware, MW150 is without precedent as an isoform selective p38MAPK inhibitor or as a kinase inhibitor capable of modulating in vivo stress related behavior. PMID:25676389

Impairment of glutamate signaling in mouse central nervous system neurons in vitro by tri-ortho-cresyl phosphate at noncytotoxic concentrations.

PubMed

Hausherr, Vanessa; van Thriel, Christoph; Krug, Anne; Leist, Marcel; Schöbel, Nicole

2014-11-01

Occupational and environmental exposure to tri-cresyl phosphates (TCPs) may cause various types of neurotoxicity. Among the TCP isomers, tri-ortho-cresyl phosphate is a well-studied organophosphate (OP) known to cause OP-induced delayed neuropathy (OPIDN). Clinically, OPIDN is characterized by limb paralysis caused by the inhibition of neuropathy target esterase. Like other OPs, TOCP may also trigger acute toxicity by yet unknown mechanisms. Neurotoxic effects of TCPs, including TOCP, on central nervous system functions have not been studied in depth, and such non-OPIDN mechanisms might be related to the aerotoxic syndrome. To identify alternative mechanisms of TOCP neurotoxicity, we conducted an in vitro study using primary cortical neurons isolated from mouse embryos (E 16.5). After 24 h or 6 days in vitro (DIV), cell cultures were treated with different TOCP concentrations for 24 h. On DIV 2 and 7, we investigated three different endpoints--general cytotoxicity, neurite outgrowth, and glutamatergic signaling. At both time points, the EC50 for TOCP-induced cell death was 90 μM, however, neurite outgrowth was already significantly affected at TOCP concentrations of 10 μM. The number of cells responding to glutamate, as well as the corresponding mean response amplitudes were reduced with TOCP concentrations as low as 100 nM. For the first time, functional neurotoxicity is observed with very low TOCP concentrations, and in the absence of structural damages. Our proposed mechanism is that TOCP exposure may lead to cognitive deficits relevant in aerotoxic syndrome by inhibiting the signaling of glutamate, the most abundant excitatory neurotransmitter in the brain. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Autosomal Recessive Mental Retardation, Deafness, Ankylosis, and Mild Hypophosphatemia Associated with a Novel ANKH Mutation in a Consanguineous Family

PubMed Central

Morava, Eva; Kühnisch, Jirko; Drijvers, Jefte M.; Robben, Joris H.; Cremers, Cor; van Setten, Petra; Branten, Amanda; Stumpp, Sabine; de Jong, Alphons; Voesenek, Krysta; Vermeer, Sascha; Heister, Angelien; Claahsen-van der Grinten, Hedi L.; O'Neill, Charles W.; Willemsen, Michèl A.; Lefeber, Dirk; Deen, Peter M. T.; Kornak, Uwe; Kremer, Hannie; Wevers, Ron A.

2011-01-01

Context: Mutations in ANKH cause the highly divergent conditions familial chondrocalcinosis and craniometaphyseal dysplasia. The gene product ANK is supposed to regulate tissue mineralization by transporting pyrophosphate to the extracellular space. Objective: We evaluated several family members of a large consanguineous family with mental retardation, deafness, and ankylosis. We compared their skeletal, metabolic, and serological parameters to that of the autosomal recessive progressive ankylosis (ank) mouse mutant, caused by a loss-of-function mutation in the murine ortholog Ank. Participants: The studied patients had painful small joint soft-tissue calcifications, progressive spondylarthropathy, osteopenia, mild hypophosphatemia, mixed hearing loss, and mental retardation. Results: After mapping the disease gene to 5p15, we identified the novel homozygous ANK missense mutation L244S in all patients. Although L244 is a highly conserved amino acid, the mutated ANK protein was detected at normal levels at the plasma membrane in primary patient fibroblasts. The phenotype was highly congruent with the autosomal recessive progressive ankylosis (ank) mouse mutant. This indicates a loss-of-function effect of the L244S mutation despite normal ANK protein expression. Interestingly, our analyses revealed that the primary step of joint degeneration is fibrosis and mineralization of articular soft tissues. Moreover, heterozygous carriers of the L244S mutation showed mild osteoarthritis without metabolic alterations, pathological calcifications, or central nervous system involvement. Conclusion: Beyond the description of the first human progressive ankylosis phenotype, our results indicate that ANK influences articular soft tissues commonly involved in degenerative joint disorders. Furthermore, this human disorder provides the first direct evidence for a role of ANK in the central nervous system. PMID:20943778

Autosomal recessive mental retardation, deafness, ankylosis, and mild hypophosphatemia associated with a novel ANKH mutation in a consanguineous family.

PubMed

Morava, Eva; Kühnisch, Jirko; Drijvers, Jefte M; Robben, Joris H; Cremers, Cor; van Setten, Petra; Branten, Amanda; Stumpp, Sabine; de Jong, Alphons; Voesenek, Krysta; Vermeer, Sascha; Heister, Angelien; Claahsen-van der Grinten, Hedi L; O'Neill, Charles W; Willemsen, Michèl A; Lefeber, Dirk; Deen, Peter M T; Kornak, Uwe; Kremer, Hannie; Wevers, Ron A

2011-01-01

Mutations in ANKH cause the highly divergent conditions familial chondrocalcinosis and craniometaphyseal dysplasia. The gene product ANK is supposed to regulate tissue mineralization by transporting pyrophosphate to the extracellular space. We evaluated several family members of a large consanguineous family with mental retardation, deafness, and ankylosis. We compared their skeletal, metabolic, and serological parameters to that of the autosomal recessive progressive ankylosis (ank) mouse mutant, caused by a loss-of-function mutation in the murine ortholog Ank. The studied patients had painful small joint soft-tissue calcifications, progressive spondylarthropathy, osteopenia, mild hypophosphatemia, mixed hearing loss, and mental retardation. After mapping the disease gene to 5p15, we identified the novel homozygous ANK missense mutation L244S in all patients. Although L244 is a highly conserved amino acid, the mutated ANK protein was detected at normal levels at the plasma membrane in primary patient fibroblasts. The phenotype was highly congruent with the autosomal recessive progressive ankylosis (ank) mouse mutant. This indicates a loss-of-function effect of the L244S mutation despite normal ANK protein expression. Interestingly, our analyses revealed that the primary step of joint degeneration is fibrosis and mineralization of articular soft tissues. Moreover, heterozygous carriers of the L244S mutation showed mild osteoarthritis without metabolic alterations, pathological calcifications, or central nervous system involvement. Beyond the description of the first human progressive ankylosis phenotype, our results indicate that ANK influences articular soft tissues commonly involved in degenerative joint disorders. Furthermore, this human disorder provides the first direct evidence for a role of ANK in the central nervous system.

Genetic inactivation of the vesicular glutamate transporter 2 (VGLUT2) in the mouse: what have we learnt about functional glutamatergic neurotransmission?

PubMed

Wallén-Mackenzie, Asa; Wootz, Hanna; Englund, Hillevi

2010-02-01

During the past decade, three proteins that possess the capability of packaging glutamate into presynaptic vesicles have been identified and characterized. These three vesicular glutamate transporters, VGLUT1-3, are encoded by solute carrier genes Slc17a6-8. VGLUT1 (Slc17a7) and VGLUT2 (Slc17a6) are expressed in glutamatergic neurons, while VGLUT3 (Slc17a8) is expressed in neurons classically defined by their use of another transmitter, such as acetylcholine and serotonin. As glutamate is both a ubiquitous amino acid and the most abundant neurotransmitter in the adult central nervous system, the discovery of the VGLUTs made it possible for the first time to identify and specifically target glutamatergic neurons. By molecular cloning techniques, different VGLUT isoforms have been genetically targeted in mice, creating models with alterations in their glutamatergic signalling. Glutamate signalling is essential for life, and its excitatory function is involved in almost every neuronal circuit. The importance of glutamatergic signalling was very obvious when studying full knockout models of both VGLUT1 and VGLUT2, none of which were compatible with normal life. While VGLUT1 full knockout mice die after weaning, VGLUT2 full knockout mice die immediately after birth. Many neurological diseases have been associated with altered glutamatergic signalling in different brain regions, which is why conditional knockout mice with abolished VGLUT-mediated signalling only in specific circuits may prove helpful in understanding molecular mechanisms behind such pathologies. We review the recent studies in which mouse genetics have been used to characterize the functional role of VGLUT2 in the central nervous system.

Localization of organ-specific antigens in the nervous system of the rat.

PubMed

Weinrauder, H; Lach, B

1977-08-16

Localization of organ-specific brain antigens in the central nervous system of the rat has been studied by means of indirect immunofluorescence. Rabbit antiserum against homogenate of rat brain, previously absorbed with normal serum and homogenates of rat organs (kidney, liver, spleen), reacted with the water-soluble antigens of rat brain prepared by extraction with phosphate buffer (pH 7.3) and ultracentrifugation at 50 000 X g to give one band in the immunodiffusion test and 2--3 precipitation arcs in immunoelectrophoresis. There was also a positive reaction with peripheral nerve. The antigen was detectable in all regions of the CNS. Cells with distinct cytoplasmic immunofluorescence were most frequently observed in cerebellar white matter, pons, cerebellar pedunculi, longitudinal tracts of the brain stem. Positive immunofluorecence reaction has appeared in the outer plexiform layer and granular layer of the retina, satelite cells of the spinal root ganglia and Schwann cells. A similar reaction was observed in human, mouse and guinea pig brain slices. Both the morphological and immunochemical reactions are indicative of glial localization of this antigen.

Nitric oxide negatively regulates mammalian adult neurogenesis

NASA Astrophysics Data System (ADS)

Packer, Michael A.; Stasiv, Yuri; Benraiss, Abdellatif; Chmielnicki, Eva; Grinberg, Alexander; Westphal, Heiner; Goldman, Steven A.; Enikolopov, Grigori

2003-08-01

Neural progenitor cells are widespread throughout the adult central nervous system but only give rise to neurons in specific loci. Negative regulators of neurogenesis have therefore been postulated, but none have yet been identified as subserving a significant role in the adult brain. Here we report that nitric oxide (NO) acts as an important negative regulator of cell proliferation in the adult mammalian brain. We used two independent approaches to examine the function of NO in adult neurogenesis. In a pharmacological approach, we suppressed NO production in the rat brain by intraventricular infusion of an NO synthase inhibitor. In a genetic approach, we generated a null mutant neuronal NO synthase knockout mouse line by targeting the exon encoding active center of the enzyme. In both models, the number of new cells generated in neurogenic areas of the adult brain, the olfactory subependyma and the dentate gyrus, was strongly augmented, which indicates that division of neural stem cells in the adult brain is controlled by NO and suggests a strategy for enhancing neurogenesis in the adult central nervous system.

Regulation of axonal and dendritic growth by the extracellular calcium-sensing receptor (CaSR)

PubMed Central

Vizard, Thomas N.; O'Keeffe, Gerard W.; Gutierrez, Humberto; Kos, Claudine H.; Riccardi, Daniela; Davies, Alun M.

2009-01-01

The extracellular calcium-sensing receptor (CaSR) monitors the systemic extracellular free ionized calcium level ([Ca2+]o) in organs involved in systemic [Ca2+]o homeostasis. However, the CaSR is also expressed in the nervous system where its role is unknown. Here we find high levels of the CaSR in perinatal mouse sympathetic neurons when their axons are innervating and branching extensively in their targets. Manipulating CaSR function in these neurons by varying [Ca2+]o, using CaSR agonists and antagonists or expressing a dominant-negative CaSR markedly affects neurite growth in vitro Sympathetic neurons lacking the CaSR have smaller neurite arbors in vitro, and sympathetic innervation density is reduced in CaSR-deficient mice in vivo. Hippocampal pyramidal neurons, which also express the CaSR, have smaller dendrites when transfected with dominant-negative CaSR in postnatal organotypic cultures. Our findings reveal a crucial role for the CaSR in regulating the growth of neural processes in the peripheral and central nervous systems. PMID:18223649

Central Nervous System Delivery of Helper-Dependent Canine Adenovirus Corrects Neuropathology and Behavior in Mucopolysaccharidosis Type VII Mice

PubMed Central

Ariza, Lorena; Giménez-Llort, Lydia; Cubizolle, Aurélie; Pagès, Gemma; García-Lareu, Belén; Serratrice, Nicolas; Cots, Dan; Thwaite, Rosemary; Chillón, Miguel; Kremer, Eric J.

2014-01-01

Abstract Canine adenovirus type 2 vectors (CAV-2) are promising tools to treat global central nervous system (CNS) disorders because of their preferential transduction of neurons and efficient retrograde axonal transport. Here we tested the potential of a helper-dependent CAV-2 vector expressing β-glucuronidase (HD-RIGIE) in a mouse model of mucopolysaccharidosis type VII (MPS VII), a lysosomal storage disease caused by deficiency in β-glucuronidase activity. MPS VII leads to glycosaminoglycan accumulation into enlarged vesicles in peripheral tissues and the CNS, resulting in peripheral and neuronal dysfunction. After intracranial administration of HD-RIGIE, we show long-term expression of β-glucuronidase that led to correction of neuropathology around the injection site and in distal areas. This phenotypic correction correlated with a decrease in secondary-elevated lysosomal enzyme activity and glycosaminoglycan levels, consistent with global biochemical correction. Moreover, HD-RIGIE-treated mice show significant cognitive improvement. Thus, injections of HD-CAV-2 vectors in the brain allow a global and sustained expression and may have implications for brain therapy in patients with lysosomal storage disease. PMID:24299455

A human-specific mutation leads to the origin of a novel splice form of neuropsin (KLK8), a gene involved in learning and memory.

PubMed

Lu, Zhi-xiang; Peng, Jia; Su, Bing

2007-10-01

Neuropsin (kallikrein 8, KLK8) is a secreted-type serine protease preferentially expressed in the central nervous system and involved in learning and memory. Its splicing pattern is different in human and mouse, with the longer form (type II) only expressed in human. Sequence analysis suggested a recent origin of type II during primate evolution. Here we demonstrate that the type II form is absent in nonhuman primates, and is thus a human-specific splice form. With the use of an in vitro splicing assay, we show that a human-specific T to A mutation (c.71-127T>A) triggers the change of splicing pattern, leading to the origin of a novel splice form in the human brain. Using mutation assay, we prove that this mutation is not only necessary but also sufficient for type II expression. Our results demonstrate a molecular mechanism for the creation of novel proteins through alternative splicing in the central nervous system during human evolution. Copyright 2007 Wiley-Liss, Inc.

An option space for early neural evolution.

PubMed

Jékely, Gáspár; Keijzer, Fred; Godfrey-Smith, Peter

2015-12-19

The origin of nervous systems has traditionally been discussed within two conceptual frameworks. Input-output models stress the sensory-motor aspects of nervous systems, while internal coordination models emphasize the role of nervous systems in coordinating multicellular activity, especially muscle-based motility. Here we consider both frameworks and apply them to describe aspects of each of three main groups of phenomena that nervous systems control: behaviour, physiology and development. We argue that both frameworks and all three aspects of nervous system function need to be considered for a comprehensive discussion of nervous system origins. This broad mapping of the option space enables an overview of the many influences and constraints that may have played a role in the evolution of the first nervous systems. © 2015 The Author(s).

Differential expression of neuroligin genes in the nervous system of zebrafish.

PubMed

Davey, Crystal; Tallafuss, Alexandra; Washbourne, Philip

2010-02-01

The establishment and maturation of appropriate synaptic connections is crucial in the development of neuronal circuits. Cellular adhesion is believed to play a central role in this process. Neuroligins are neuronal cell adhesion molecules that are hypothesized to act in the initial formation and maturation of synaptic connections. In order to establish the zebrafish as a model to investigate the in vivo role of Neuroligin proteins in nervous system development, we identified the zebrafish orthologs of neuroligin family members and characterized their expression. Zebrafish possess seven neuroligin genes. Synteny analysis and sequence comparisons show that NLGN2, NLGN3, and NLGN4X are duplicated in zebrafish, but NLGN1 has a single zebrafish ortholog. All seven zebrafish neuroligins are expressed in complex patterns in the developing nervous system and in the adult brain. The spatial and temporal expression patterns of these genes suggest that they occupy a role in nervous system development and maintenance.

Sialic Acids in the Brain: Gangliosides and Polysialic Acid in Nervous System Development, Stability, Disease, and Regeneration

PubMed Central

Gerardy-Schahn, Rita; Hildebrandt, Herbert

2014-01-01

Every cell in nature carries a rich surface coat of glycans, its glycocalyx, which constitutes the cell's interface with its environment. In eukaryotes, the glycocalyx is composed of glycolipids, glycoproteins, and proteoglycans, the compositions of which vary among different tissues and cell types. Many of the linear and branched glycans on cell surface glycoproteins and glycolipids of vertebrates are terminated with sialic acids, nine-carbon sugars with a carboxylic acid, a glycerol side-chain, and an N-acyl group that, along with their display at the outmost end of cell surface glycans, provide for varied molecular interactions. Among their functions, sialic acids regulate cell-cell interactions, modulate the activities of their glycoprotein and glycolipid scaffolds as well as other cell surface molecules, and are receptors for pathogens and toxins. In the brain, two families of sialoglycans are of particular interest: gangliosides and polysialic acid. Gangliosides, sialylated glycosphingolipids, are the most abundant sialoglycans of nerve cells. Mouse genetic studies and human disorders of ganglioside metabolism implicate gangliosides in axon-myelin interactions, axon stability, axon regeneration, and the modulation of nerve cell excitability. Polysialic acid is a unique homopolymer that reaches >90 sialic acid residues attached to select glycoproteins, especially the neural cell adhesion molecule in the brain. Molecular, cellular, and genetic studies implicate polysialic acid in the control of cell-cell and cell-matrix interactions, intermolecular interactions at cell surfaces, and interactions with other molecules in the cellular environment. Polysialic acid is essential for appropriate brain development, and polymorphisms in the human genes responsible for polysialic acid biosynthesis are associated with psychiatric disorders including schizophrenia, autism, and bipolar disorder. Polysialic acid also appears to play a role in adult brain plasticity, including regeneration. Together, vertebrate brain sialoglycans are key regulatory components that contribute to proper development, maintenance, and health of the nervous system. PMID:24692354

A RET-ER81-NRG1 Signaling Pathway Drives the Development of Pacinian Corpuscles.

PubMed

Fleming, Michael S; Li, Jian J; Ramos, Daniel; Li, Tong; Talmage, David A; Abe, Shin-Ichi; Arber, Silvia; Luo, Wenqin

2016-10-05

Axon-Schwann cell interactions are crucial for the development, function, and repair of the peripheral nervous system, but mechanisms underlying communication between axons and nonmyelinating Schwann cells are unclear. Here, we show that ER81 is functionally required in a subset of mouse RET + mechanosensory neurons for formation of Pacinian corpuscles, which are composed of a single myelinated axon and multiple layers of nonmyelinating Schwann cells, and Ret is required for the maintenance of Er81 expression. Interestingly, Er81 mutants have normal myelination but exhibit deficient interactions between axons and corpuscle-forming nonmyelinating Schwann cells. Finally, ablating Neuregulin-1 (Nrg1) in mechanosensory neurons results in no Pacinian corpuscles, and an Nrg1 isoform not required for communication with myelinating Schwann cells is specifically decreased in Er81-null somatosensory neurons. Collectively, our results suggest that a RET-ER81-NRG1 signaling pathway promotes axon communication with nonmyelinating Schwann cells, and that neurons use distinct mechanisms to interact with different types of Schwann cells. Communication between neurons and Schwann cells is critical for development, normal function, and regeneration of the peripheral nervous system. Despite many studies about axonal communication with myelinating Schwann cells, mostly via a specific isoform of Neuregulin1, the molecular nature of axonal communication with nonmyelinating Schwann cells is poorly understood. Here, we described a RET-ER81-Neuregulin1 signaling pathway in neurons innervating Pacinian corpuscle somatosensory end organs, which is essential for communication between the innervating axon and the end organ nonmyelinating Schwann cells. We also showed that this signaling pathway uses isoforms of Neuregulin1 that are not involved in myelination, providing evidence that neurons use different isoforms of Neuregulin1 to interact with different types of Schwann cells. Copyright © 2016 the authors 0270-6474/16/3610337-19$15.00/0.

76 FR 18915 - Ethiprole; Pesticide Tolerances

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-06

... homeostasis and the developing nervous system in the young is not available. Based on a battery of... of the nervous system, the Agency is requiring a developmental thyroid toxicity study to assess for... nervous system, the Agency is requiring the developmental thyroid toxicity study in lieu of the DNT. iii...

77 FR 65582 - Pfizer Therapeutic Research, Pfizer Worldwide Reasearch & Development Division, Formerly Known as...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-29

..., Central Nervous System Research Unit (Currently Known as Neuroscience Research Unit), Global External... as Warner Lambert Company, Central Nervous System Research Unit, Global External Supply Department... Central Nervous System Research Unit was renamed the Neuroscience Research Unit. In order to ensure proper...

Retinoic acid influences anteroposterior positioning of epidermal sensory neurons and their gene expression in a developing chordate (amphioxus)

PubMed Central

Schubert, Michael; Holland, Nicholas D.; Escriva, Hector; Holland, Linda Z.; Laudet, Vincent

2004-01-01

In developing chordates, retinoic acid (RA) signaling patterns the rostrocaudal body axis globally and affects gene expression locally in some differentiating cell populations. Here we focus on development of epidermal sensory neurons in an invertebrate chordate (amphioxus) to determine how RA signaling influences their rostrocaudal distribution and gene expression (for AmphiCoe, a neural precursor gene; for amphioxus islet and AmphiERR, two neural differentiation genes; and for AmphiHox1, -3, -4, and -6). Treatments with RA or an RA antagonist (BMS009) shift the distribution of developing epidermal neurons anteriorly or posteriorly, respectively. These treatments also affect gene expression patterns in the epidermal neurons, suggesting that RA levels may influence specification of neuronal subtypes. Although colinear expression of Hox genes is well known for the amphioxus central nervous system, we find an unexpected comparable colinearity for AmphiHox1, -3, -4, and -6 in the developing epidermis; moreover, RA levels affect the anteroposterior extent of these Hox expression domains, suggesting that RA signaling controls a colinear Hox code for anteroposterior patterning of the amphioxus epidermis. Thus, in amphioxus, the developing peripheral nervous system appears to be structured by mechanisms parallel to those that structure the central nervous system. One can speculate that, during evolution, an ancestral deuterostome that structured its panepidermal nervous system with an RA-influenced Hox code gave rise to chordates in which this patterning mechanism persisted within the epidermal elements of the peripheral nervous system and was transferred to the neuroectoderm as the central nervous system condensed dorsally. PMID:15226493

New insight into the role of the β3 subunit of the GABAA-R in development, behavior, body weight regulation, and anesthesia revealed by conditional gene knockout

PubMed Central

Ferguson, Carolyn; Hardy, Steven L; Werner, David F; Hileman, Stanley M; DeLorey, Timothy M; Homanics, Gregg E

2007-01-01

Background The β3 subunit of the γ-aminobutyric acid type A receptor (GABAA-R) has been reported to be important for palate formation, anesthetic action, and normal nervous system function. This subunit has also been implicated in the pathogenesis of Angelman syndrome and autism spectrum disorder. To further investigate involvement of this subunit, we previously produced mice with a global knockout of β3. However, developmental abnormalities, compensation, reduced viability, and numerous behavioral abnormalities limited the usefulness of that murine model. To overcome many of these limitations, a mouse line with a conditionally inactivated β3 gene was engineered. Results Gene targeting and embryonic stem cell technologies were used to create mice in which exon 3 of the β3 subunit was flanked by loxP sites (i.e., floxed). Crossing the floxed β3 mice to a cre general deleter mouse line reproduced the phenotype of the previously described global knockout. Pan-neuronal knockout of β3 was achieved by crossing floxed β3 mice to Synapsin I-cre transgenic mice. Palate development was normal in pan-neuronal β3 knockouts but ~61% died as neonates. Survivors were overtly normal, fertile, and were less sensitive to etomidate. Forebrain selective knockout of β3 was achieved using α CamKII-cre transgenic mice. Palate development was normal in forebrain selective β3 knockout mice. These knockouts survived the neonatal period, but ~30% died between 15–25 days of age. Survivors had reduced reproductive fitness, reduced sensitivity to etomidate, were hyperactive, and some became obese. Conclusion Conditional inactivation of the β3 gene revealed novel insight into the function of this GABAA-R subunit. The floxed β3 knockout mice described here will be very useful for conditional knockout studies to further investigate the role of the β3 subunit in development, ethanol and anesthetic action, normal physiology, and pathophysiologic processes. PMID:17927825

[Molecular genetics of familial tumour syndromes of the central nervous system].

PubMed

Murnyák, Balázs; Szepesi, Rita; Hortobágyi, Tibor

2015-02-01

Although most of the central nervous system tumours are sporadic, rarely they are associated with familial tumour syndromes. These disorders usually present with an autosomal dominant inheritance and neoplasia develops at younger age than in sporadic cases. Most of these tumours are bilateral, multiplex or multifocal. The causative mutations occur in genes involved in cell cycle regulation, cell growth, differentiation and DNA repair. Studying these hereditary cancer predisposition syndromes associated with nervous system tumours can facilitate the deeper understanding of the molecular background of sporadic tumours and the development of novel therapeutic agents. This review is an update on hereditary tumour syndromes with nervous system involvement with emphasis on molecular genetic characteristics and their clinical implications.

Evidence for Altered Ca2+ Handling in Growth Associated Protein 43-Knockout Skeletal Muscle

PubMed Central

Caprara, Giusy A.; Morabito, Caterina; Perni, Stefano; Navarra, Riccardo; Guarnieri, Simone; Mariggiò, Maria A.

2016-01-01

Neuronal growth-associated protein 43 (GAP43) has crucial roles in the nervous system, and during development, regeneration after injury, and learning and memory. GAP43 is expressed in mouse skeletal muscle fibers and satellite cells, with suggested its involvement in intracellular Ca2+ handling. However, the physiological role of GAP43 in muscle remains unknown. Using a GAP43-knockout (GAP43−/−) mouse, we have defined the role of GAP43 in skeletal muscle. GAP43−/− mice showed low survival beyond weaning, reduced adult body weight, decreased muscle strength, and changed myofiber ultrastructure, with no significant differences in the expression of markers of satellite cell and myotube progression through the myogenic program. Thus, GAP43 expression is involved in timing of muscle maturation in-vivo. Intracellular Ca2+ measurements in-vitro in myotubes revealed GAP43 involvement in Ca2+ handling. In the absence of GAP43 expression, the spontaneous Ca2+ variations had greater amplitudes and higher frequency. In GAP43−/− myotubes, also the intracellular Ca2+ variations induced by the activation of dihydropyridine and ryanodine Ca2+ channels, resulted modified. These evidences suggested dysregulation of Ca2+ homeostasis. The emerging hypothesis indicates that GAP43 interacts with calmodulin to indirectly modulate the activities of dihydropyridine and ryanodine Ca2+ channels. This thus influences intracellular Ca2+ dynamics and its related intracellular patterns, from functional excitation-contraction coupling, to cell metabolism, and gene expression. PMID:27833566

Perinatal western-type diet and associated gestational weight gain alter postpartum maternal mood.

PubMed

Bolton, Jessica L; Wiley, Melanie G; Ryan, Bailey; Truong, Samantha; Strait, Melva; Baker, Dana Creighton; Yang, Nancy Y; Ilkayeva, Olga; O'Connell, Thomas M; Wroth, Shelley W; Sánchez, Cristina L; Swamy, Geeta; Newgard, Christopher; Kuhn, Cynthia; Bilbo, Staci D; Simmons, Leigh Ann

2017-10-01

The role of perinatal diet in postpartum maternal mood disorders, including depression and anxiety, remains unclear. We investigated whether perinatal consumption of a Western-type diet (high in fat and branched-chain amino acids [BCAA]) and associated gestational weight gain (GWG) cause serotonin dysregulation in the central nervous system (CNS), resulting in postpartum depression and anxiety (PPD/A). Mouse dams were fed one of four diets (high-fat/high BCAA, low-fat/high BCAA, high-fat, and low-fat) prior to mating and throughout gestation and lactation. Postpartum behavioral assessments were conducted, and plasma and brain tissues assayed. To evaluate potential clinical utility, we conducted preliminary human studies using data from an extant sample of 17 primiparous women with high GWG, comparing across self-reported postpartum mood symptoms using the Edinburgh Postnatal Depression Scale (EPDS) for percent GWG and plasma amino acid levels. Mouse dams fed the high-fat/high BCAA diet gained more weight per kcal consumed, and BCAA-supplemented dams lost weight more slowly postpartum. Dams on BCAA-supplemented diets exhibited increased PPD/A-like behavior, decreased dopaminergic function, and decreased plasma tyrosine and histidine levels when assessed on postnatal day (P)8. Preliminary human data showed that GWG accounted for 29% of the variance in EPDS scores. Histidine was also lower in women with higher EPDS scores. These findings highlight the role of perinatal diet and excess GWG in the development of postpartum mood disorders.

GAL3 receptor KO mice exhibit an anxiety-like phenotype

PubMed Central

Brunner, Susanne M.; Farzi, Aitak; Locker, Felix; Holub, Barbara S.; Drexel, Meinrad; Reichmann, Florian; Lang, Andreas A.; Mayr, Johannes A.; Vilches, Jorge J.; Navarro, Xavier; Lang, Roland; Sperk, Günther; Holzer, Peter; Kofler, Barbara

2014-01-01

The neuropeptide galanin (GAL) is widely distributed in the central and peripheral nervous systems. It is a modulator of various physiological and pathological processes, and it mediates its effects via three G protein-coupled receptors (GAL1–3 receptors). A role for GAL as a modulator of mood and anxiety was suggested, because GAL and its receptors are highly expressed in limbic brain structures of rodents. In recent years, numerous studies of animal models have suggested an involvement of GAL and GAL1 and GAL2 receptors in anxiety- and depression-related behavior. However, to date, there is sparse literature implicating GAL3 receptors in behavioral functions. Therefore, we studied the behavior of GAL3 receptor-deficient (GAL3-KO) mice to elucidate whether GAL3 receptors are involved in mediating behavior-associated actions of GAL. The GAL3-KO mouse line exhibited normal breeding and physical development. In addition to behavioral tests, phenotypic characterization included analysis of hematology, amino acid profiles, metabolism, and sudomotor function. In contrast to WT littermates, male GAL3-KO mice exhibited an anxiety-like phenotype in the elevated plus maze, open field, and light/dark box tests, and they were less socially affiliated than WT animals to a stranger mouse in a social interaction test. In conclusion, our data suggest involvement of GAL3 receptors in GAL-mediated effects on mood, anxiety, and behavior, making it a possible target for alternative treatment strategies for mood disorders. PMID:24782539

PhosphoregDB: The tissue and sub-cellular distribution of mammalian protein kinases and phosphatases

PubMed Central

Forrest, Alistair RR; Taylor, Darrin F; Fink, J Lynn; Gongora, M Milena; Flegg, Cameron; Teasdale, Rohan D; Suzuki, Harukazu; Kanamori, Mutsumi; Kai, Chikatoshi; Hayashizaki, Yoshihide; Grimmond, Sean M

2006-01-01

Background Protein kinases and protein phosphatases are the fundamental components of phosphorylation dependent protein regulatory systems. We have created a database for the protein kinase-like and phosphatase-like loci of mouse that integrates protein sequence, interaction, classification and pathway information with the results of a systematic screen of their sub-cellular localization and tissue specific expression data mined from the GNF tissue atlas of mouse. Results The database lets users query where a specific kinase or phosphatase is expressed at both the tissue and sub-cellular levels. Similarly the interface allows the user to query by tissue, pathway or sub-cellular localization, to reveal which components are co-expressed or co-localized. A review of their expression reveals 30% of these components are detected in all tissues tested while 70% show some level of tissue restriction. Hierarchical clustering of the expression data reveals that expression of these genes can be used to separate the samples into tissues of related lineage, including 3 larger clusters of nervous tissue, developing embryo and cells of the immune system. By overlaying the expression, sub-cellular localization and classification data we examine correlations between class, specificity and tissue restriction and show that tyrosine kinases are more generally expressed in fewer tissues than serine/threonine kinases. Conclusion Together these data demonstrate that cell type specific systems exist to regulate protein phosphorylation and that for accurate modelling and for determination of enzyme substrate relationships the co-location of components needs to be considered. PMID:16504016

Analysis of maternal-zygotic ugdh mutants reveals divergent roles for HSPGs in vertebrate embryogenesis and provides new insight into the initiation of left-right asymmetry.

PubMed

Superina, Simone; Borovina, Antonia; Ciruna, Brian

2014-03-15

Growth factors and morphogens regulate embryonic patterning, cell fate specification, cell migration, and morphogenesis. The activity and behavior of these signaling molecules are regulated in the extracellular space through interactions with proteoglycans (Bernfield et al., 1999; Perrimon and Bernfield 2000; Lander and Selleck 2000; Selleck 2000). Proteoglycans are high molecular-weight proteins consisting of a core protein with covalently linked glycosaminoglycan (GAG) side chains, which are thought to mediate ligand interaction. Drosophila mutant embryos deficient for UDP-glucose dehydrogenase activity (Ugdh, required for GAG synthesis) exhibit abnormal Fgf, Wnt and TGFß signaling and die during gastrulation, indicating a broad and critical role for proteoglycans during early embryonic development (Lin et al., 1999; Lin and Perrimon 2000) (Hacker et al., 1997). Mouse Ugdh mutants also die at gastrulation, however, only Fgf signaling appears disrupted (Garcia-Garcia and Anderson, 2003). These findings suggested a possible divergence in the requirement for proteoglycans during Drosophila and mouse embryogenesis, and that mammals may have evolved alternative means of regulating Wnt and TGFß activity. To further examine the function of proteoglycans in vertebrate development, we have characterized zebrafish mutants devoid of both maternal and zygotic Ugdh/Jekyll activity (MZjekyll). We demonstrate that MZjekyll mutant embryos display abnormal Fgf, Shh, and Wnt signaling activities, with concomitant defects in central nervous system patterning, cardiac ventricular fate specification and axial morphogenesis. Furthermore, we uncover a novel role for proteoglycans in left-right pattern formation. Our findings resolve longstanding questions into the evolutionary conservation of Ugdh function and provide new mechanistic insights into the initiation of left-right asymmetry. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

CDKL5 expression is modulated during neuronal development and its subcellular distribution is tightly regulated by the C-terminal tail.

PubMed

Rusconi, Laura; Salvatoni, Lisa; Giudici, Laura; Bertani, Ilaria; Kilstrup-Nielsen, Charlotte; Broccoli, Vania; Landsberger, Nicoletta

2008-10-31

Mutations in the human X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in patients with Rett syndrome (RTT), West syndrome, and X-linked infantile spasms, sharing the common feature of mental retardation and early seizures. CDKL5 is a rather uncharacterized kinase, but its involvement in RTT seems to be explained by the fact that it works upstream of MeCP2, the main cause of Rett syndrome. To understand the role of this kinase for nervous system functions and to address if molecular mechanisms are involved in regulating its distribution and activity, we studied the ontogeny of CDKL5 expression in developing mouse brains by immunostaining and Western blotting. The expression profile of CDKL5 was compared with that of MeCP2. The two proteins share a general expression profile in the adult mouse brain, but CDKL5 levels appear to be highly modulated at the regional level. Its expression is strongly induced in early postnatal stages, and in the adult brain CDKL5 is present in mature neurons, but not in astroglia. Interestingly, the presence of CDKL5 in the cell nucleus varies at the regional level of the adult brain and is developmentally regulated. CDKL5 shuttles between the cytoplasm and the nucleus and the C-terminal tail is involved in localizing the protein to the cytoplasm in a mechanism depending on active nuclear export. Accordingly, Rett derivatives containing disease-causing truncations of the C terminus are constitutively nuclear, suggesting that they might act as gain of function mutations in this cellular compartment.

Relationship between individual neuron and network spontaneous activity in developing mouse cortex.

PubMed

Barnett, Heather M; Gjorgjieva, Julijana; Weir, Keiko; Comfort, Cara; Fairhall, Adrienne L; Moody, William J

2014-12-15

Spontaneous synchronous activity (SSA) that propagates as electrical waves is found in numerous central nervous system structures and is critical for normal development, but the mechanisms of generation of such activity are not clear. In previous work, we showed that the ventrolateral piriform cortex is uniquely able to initiate SSA in contrast to the dorsal neocortex, which participates in, but does not initiate, SSA (Lischalk JW, Easton CR, Moody WJ. Dev Neurobiol 69: 407-414, 2009). In this study, we used Ca(2+) imaging of cultured embryonic day 18 to postnatal day 2 coronal slices (embryonic day 17 + 1-4 days in culture) of the mouse cortex to investigate the different activity patterns of individual neurons in these regions. In the piriform cortex where SSA is initiated, a higher proportion of neurons was active asynchronously between waves, and a larger number of groups of coactive cells was present compared with the dorsal cortex. When we applied GABA and glutamate synaptic antagonists, asynchronous activity and cellular clusters remained, while synchronous activity was eliminated, indicating that asynchronous activity is a result of cell-intrinsic properties that differ between these regions. To test the hypothesis that higher levels of cell-autonomous activity in the piriform cortex underlie its ability to initiate waves, we constructed a conductance-based network model in which three layers differed only in the proportion of neurons able to intrinsically generate bursting behavior. Simulations using this model demonstrated that a gradient of intrinsic excitability was sufficient to produce directionally propagating waves that replicated key experimental features, indicating that the higher level of cell-intrinsic activity in the piriform cortex may provide a substrate for SSA generation. Copyright © 2014 the American Physiological Society.

The Stimulus-Dependent Gradient of Cyp26B1+ Olfactory Sensory Neurons Is Necessary for the Functional Integrity of the Olfactory Sensory Map.

PubMed

Login, Hande; Håglin, Sofia; Berghard, Anna; Bohm, Staffan

2015-10-07

Stimulus-dependent expression of the retinoic acid-inactivating enzyme Cyp26B1 in olfactory sensory neurons (OSNs) forms a dorsomedial (DM)-ventrolateral (VL) gradient in the mouse olfactory epithelium. The gradient correlates spatially with different rates of OSN turnover, as well as the functional organization of the olfactory sensory map, into overlapping zones of OSNs that express different odorant receptors (ORs). Here, we analyze transgenic mice that, instead of a stimulus-dependent Cyp26B1 gradient, have constitutive Cyp26B1 levels in all OSNs. Starting postnatally, OSN differentiation is decreased and progenitor proliferation is increased. Initially, these effects are selective to the VL-most zone and correlate with reduced ATF5 expression and accumulation of OSNs that do not express ORs. Transcription factor ATF5 is known to stabilize OR gene choice via onset of the stimulus-transducing enzyme adenylyl cyclase type 3. During further postnatal development of Cyp26B1 mice, an anomalous DM(high)-VL(low) expression gradient of adenylyl cyclase type 3 appears, which coincides with altered OR frequencies and OR zones. All OR zones expand ventrolaterally except for the VL-most zone, which contracts. The expansion results in an increased zonal overlap that is also evident in the innervation pattern of OSN axon terminals in olfactory bulbs. These findings together identify a mechanism by which postnatal sensory-stimulated vitamin A metabolism modifies the generation of spatially specified neurons and their precise topographic connectivity. The distributed patterns of vitamin A-metabolizing enzymes in the nervous system suggest the possibility that the mechanism may also regulate neuroplasticity in circuits other than the olfactory sensory map. The mouse olfactory sensory map is functionally wired according to precise axonal projections of spatially organized classes of olfactory sensory neurons in the nose. The genetically controlled mechanisms that regulate the development of the olfactory sensory map are beginning to be elucidated. Little is known about mechanisms by which sensory stimuli shape the organization of the map after birth. We show that a stimulus-dependent gradient of a retinoic acid-inactivating enzyme Cyp26B1 modifies the composition, localization, and axonal projections of olfactory sensory neuron classes. The mechanism is novel and suggests the interesting possibility that local vitamin A metabolism could also be a mediator of stimulus-dependent modifications of precise spatial connectivity in other parts of the nervous system. Copyright © 2015 the authors 0270-6474/15/3513807-12$15.00/0.

A novel subset of enteric neurons revealed by ptf1a:GFP in the developing zebrafish enteric nervous system.

PubMed

Uribe, Rosa A; Gu, Tiffany; Bronner, Marianne E

2016-03-01

The enteric nervous system, the largest division of the peripheral nervous system, is derived from vagal neural crest cells that invade and populate the entire length of the gut to form diverse neuronal subtypes. Here, we identify a novel population of neurons within the enteric nervous system of zebrafish larvae that express the transgenic marker ptf1a:GFP within the midgut. Genetic lineage analysis reveals that enteric ptf1a:GFP(+) cells are derived from the neural crest and that most ptf1a:GFP(+) neurons express the neurotransmitter 5HT, demonstrating that they are serotonergic. This transgenic line, Tg(ptf1a:GFP), provides a novel neuronal marker for a subpopulation of neurons within the enteric nervous system, and highlights the possibility that Ptf1a may act as an important transcription factor for enteric neuron development. © 2016 Wiley Periodicals, Inc.

Evolution of the Human Nervous System Function, Structure, and Development.

PubMed

Sousa, André M M; Meyer, Kyle A; Santpere, Gabriel; Gulden, Forrest O; Sestan, Nenad

2017-07-13

The nervous system-in particular, the brain and its cognitive abilities-is among humans' most distinctive and impressive attributes. How the nervous system has changed in the human lineage and how it differs from that of closely related primates is not well understood. Here, we consider recent comparative analyses of extant species that are uncovering new evidence for evolutionary changes in the size and the number of neurons in the human nervous system, as well as the cellular and molecular reorganization of its neural circuits. We also discuss the developmental mechanisms and underlying genetic and molecular changes that generate these structural and functional differences. As relevant new information and tools materialize at an unprecedented pace, the field is now ripe for systematic and functionally relevant studies of the development and evolution of human nervous system specializations. Copyright © 2017 Elsevier Inc. All rights reserved.

Secondary parkinsonism

MedlinePlus

... developing. Alternative Names Parkinsonism - secondary; Atypical Parkinson disease Images Central nervous system and peripheral nervous system References Jankovic J. Parkinson disease and other movement disorders. In: Daroff ...

TESTING FOR DEVELOPMENTAL NEUROTOXICITY: CURRENT APPROACHES AND FUTURE NEEDS.

EPA Science Inventory

There are many adverse effects on the nervous system following exposure to environmental chemicals during development. In a number of cases (e.g., lead, methyl mercury) the developing nervous system is a highly susceptible. Developmental Neurotoxicity Testing (DNT) guidelines...

Developmental neurotoxicity testing: Past, present and future.

EPA Science Inventory

Adverse effects on the nervous system following exposure to environmental contaminants during development have been well documented. Indeed, in a number of cases (e.g., lead, methyl mercury) the developing human nervous system appears to be a highly susceptible target. There ar...

Dual labeling of neural crest cells and blood vessels within chicken embryos using Chick(GFP) neural tube grafting and carbocyanine dye DiI injection.

PubMed

Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J

2015-05-28

All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chick(GFP) embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. Chick(GFP)-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system.

Dual Labeling of Neural Crest Cells and Blood Vessels Within Chicken Embryos Using ChickGFP Neural Tube Grafting and Carbocyanine Dye DiI Injection

PubMed Central

Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J.

2015-01-01

All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chickGFP embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. ChickGFP-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system. PMID:26065540

CERTAIN SPECIFIC FEATURES OF THE HIGHER NERVOUS ACTIVITY OF FULLY GROWN ANIMALS IRRADIATED ANTENATALLY WITH IONIZING RADIATION. I. THE INFLUENCE OF IONIZING RADIATION ON THE OFFSPRING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piontkovskii, I.A.

1958-09-01

Irradiation of pregnant female aniamals and women with ionizing radiation may cause the appearance of a variety of congenital deformities in the offspring and may interfere with their postnatal development. L. Hicks points out the particular sensitivity of the nervous system of the embryo to ionizing radiation. Thus irradiation of rats on the 9th, 11th, 12th, and 13th days of prenatal development may cause, in addition to somatic deformities, anencephaly (on the 9th day), hydrocephaly (on the 11th day), microcephaly (on the 12th13th day), failure of development of the subcortical structures, the corpora callosa and so on. The influence ofmore » ionizing radiation on the nervous system during antenatal irradiation has been studied mainly morphologically. There are no indications in the literature of the state of the higher nervous activity of fully grown animals exposed at various periods of their antenatal development to the action of ionizing radiation. The effect of ionizing radiation, applied in various doses and at different stages of embryonic development, on the state of the higher nervous activity of animals was studied. (auth)« less

The Role of Abcb5 Alleles in Susceptibility to Haloperidol-Induced Toxicity in Mice and Humans

PubMed Central

Zheng, Ming; Zhang, Haili; Dill, David L.; Clark, J. David; Tu, Susan; Yablonovitch, Arielle L.; Tan, Meng How; Zhang, Rui; Rujescu, Dan; Wu, Manhong; Tessarollo, Lino; Vieira, Wilfred; Gottesman, Michael M.; Deng, Suhua; Eberlin, Livia S.; Zare, Richard N.; Billard, Jean-Martin; Gillet, Jean-Pierre; Li, Jin Billy; Peltz, Gary

2015-01-01

Background We know very little about the genetic factors affecting susceptibility to drug-induced central nervous system (CNS) toxicities, and this has limited our ability to optimally utilize existing drugs or to develop new drugs for CNS disorders. For example, haloperidol is a potent dopamine antagonist that is used to treat psychotic disorders, but 50% of treated patients develop characteristic extrapyramidal symptoms caused by haloperidol-induced toxicity (HIT), which limits its clinical utility. We do not have any information about the genetic factors affecting this drug-induced toxicity. HIT in humans is directly mirrored in a murine genetic model, where inbred mouse strains are differentially susceptible to HIT. Therefore, we genetically analyzed this murine model and performed a translational human genetic association study. Methods and Findings A whole genome SNP database and computational genetic mapping were used to analyze the murine genetic model of HIT. Guided by the mouse genetic analysis, we demonstrate that genetic variation within an ABC-drug efflux transporter (Abcb5) affected susceptibility to HIT. In situ hybridization results reveal that Abcb5 is expressed in brain capillaries, and by cerebellar Purkinje cells. We also analyzed chromosome substitution strains, imaged haloperidol abundance in brain tissue sections and directly measured haloperidol (and its metabolite) levels in brain, and characterized Abcb5 knockout mice. Our results demonstrate that Abcb5 is part of the blood-brain barrier; it affects susceptibility to HIT by altering the brain concentration of haloperidol. Moreover, a genetic association study in a haloperidol-treated human cohort indicates that human ABCB5 alleles had a time-dependent effect on susceptibility to individual and combined measures of HIT. Abcb5 alleles are pharmacogenetic factors that affect susceptibility to HIT, but it is likely that additional pharmacogenetic susceptibility factors will be discovered. Conclusions ABCB5 alleles alter susceptibility to HIT in mouse and humans. This discovery leads to a new model that (at least in part) explains inter-individual differences in susceptibility to a drug-induced CNS toxicity. PMID:25647612

Comprehensive Identification of Long Non-coding RNAs in Purified Cell Types from the Brain Reveals Functional LncRNA in OPC Fate Determination.

PubMed

Dong, Xiaomin; Chen, Kenian; Cuevas-Diaz Duran, Raquel; You, Yanan; Sloan, Steven A; Zhang, Ye; Zong, Shan; Cao, Qilin; Barres, Ben A; Wu, Jia Qian

2015-12-01

Long non-coding RNAs (lncRNAs) (> 200 bp) play crucial roles in transcriptional regulation during numerous biological processes. However, it is challenging to comprehensively identify lncRNAs, because they are often expressed at low levels and with more cell-type specificity than are protein-coding genes. In the present study, we performed ab initio transcriptome reconstruction using eight purified cell populations from mouse cortex and detected more than 5000 lncRNAs. Predicting the functions of lncRNAs using cell-type specific data revealed their potential functional roles in Central Nervous System (CNS) development. We performed motif searches in ENCODE DNase I digital footprint data and Mouse ENCODE promoters to infer transcription factor (TF) occupancy. By integrating TF binding and cell-type specific transcriptomic data, we constructed a novel framework that is useful for systematically identifying lncRNAs that are potentially essential for brain cell fate determination. Based on this integrative analysis, we identified lncRNAs that are regulated during Oligodendrocyte Precursor Cell (OPC) differentiation from Neural Stem Cells (NSCs) and that are likely to be involved in oligodendrogenesis. The top candidate, lnc-OPC, shows highly specific expression in OPCs and remarkable sequence conservation among placental mammals. Interestingly, lnc-OPC is significantly up-regulated in glial progenitors from experimental autoimmune encephalomyelitis (EAE) mouse models compared to wild-type mice. OLIG2-binding sites in the upstream regulatory region of lnc-OPC were identified by ChIP (chromatin immunoprecipitation)-Sequencing and validated by luciferase assays. Loss-of-function experiments confirmed that lnc-OPC plays a functional role in OPC genesis. Overall, our results substantiated the role of lncRNA in OPC fate determination and provided an unprecedented data source for future functional investigations in CNS cell types. We present our datasets and analysis results via the interactive genome browser at our laboratory website that is freely accessible to the research community. This is the first lncRNA expression database of collective populations of glia, vascular cells, and neurons. We anticipate that these studies will advance the knowledge of this major class of non-coding genes and their potential roles in neurological development and diseases.

GlcNAc6ST-1 regulates sulfation of N-glycans and myelination in the peripheral nervous system

PubMed Central

Yoshimura, Takeshi; Hayashi, Akiko; Handa-Narumi, Mai; Yagi, Hirokazu; Ohno, Nobuhiko; Koike, Takako; Yamaguchi, Yoshihide; Uchimura, Kenji; Kadomatsu, Kenji; Sedzik, Jan; Kitamura, Kunio; Kato, Koichi; Trapp, Bruce D.; Baba, Hiroko; Ikenaka, Kazuhiro

2017-01-01

Highly specialized glial cells wrap axons with a multilayered myelin membrane in vertebrates. Myelin serves essential roles in the functioning of the nervous system. Axonal degeneration is the major cause of permanent neurological disability in primary myelin diseases. Many glycoproteins have been identified in myelin, and a lack of one myelin glycoprotein results in abnormal myelin structures in many cases. However, the roles of glycans on myelin glycoproteins remain poorly understood. Here, we report that sulfated N-glycans are involved in peripheral nervous system (PNS) myelination. PNS myelin glycoproteins contain highly abundant sulfated N-glycans. Major sulfated N-glycans were identified in both porcine and mouse PNS myelin, demonstrating that the 6-O-sulfation of N-acetylglucosamine (GlcNAc-6-O-sulfation) is highly conserved in PNS myelin between these species. P0 protein, the most abundant glycoprotein in PNS myelin and mutations in which at the glycosylation site cause Charcot-Marie-Tooth neuropathy, has abundant GlcNAc-6-O-sulfated N-glycans. Mice deficient in N-acetylglucosamine-6-O-sulfotransferase-1 (GlcNAc6ST-1) failed to synthesize sulfated N-glycans and exhibited abnormal myelination and axonal degeneration in the PNS. Taken together, this study demonstrates that GlcNAc6ST-1 modulates PNS myelination and myelinated axonal survival through the GlcNAc-6-O-sulfation of N-glycans on glycoproteins. These findings may provide novel insights into the pathogenesis of peripheral neuropathy. PMID:28186137

GlcNAc6ST-1 regulates sulfation of N-glycans and myelination in the peripheral nervous system.

PubMed

Yoshimura, Takeshi; Hayashi, Akiko; Handa-Narumi, Mai; Yagi, Hirokazu; Ohno, Nobuhiko; Koike, Takako; Yamaguchi, Yoshihide; Uchimura, Kenji; Kadomatsu, Kenji; Sedzik, Jan; Kitamura, Kunio; Kato, Koichi; Trapp, Bruce D; Baba, Hiroko; Ikenaka, Kazuhiro

2017-02-10

Highly specialized glial cells wrap axons with a multilayered myelin membrane in vertebrates. Myelin serves essential roles in the functioning of the nervous system. Axonal degeneration is the major cause of permanent neurological disability in primary myelin diseases. Many glycoproteins have been identified in myelin, and a lack of one myelin glycoprotein results in abnormal myelin structures in many cases. However, the roles of glycans on myelin glycoproteins remain poorly understood. Here, we report that sulfated N-glycans are involved in peripheral nervous system (PNS) myelination. PNS myelin glycoproteins contain highly abundant sulfated N-glycans. Major sulfated N-glycans were identified in both porcine and mouse PNS myelin, demonstrating that the 6-O-sulfation of N-acetylglucosamine (GlcNAc-6-O-sulfation) is highly conserved in PNS myelin between these species. P 0 protein, the most abundant glycoprotein in PNS myelin and mutations in which at the glycosylation site cause Charcot-Marie-Tooth neuropathy, has abundant GlcNAc-6-O-sulfated N-glycans. Mice deficient in N-acetylglucosamine-6-O-sulfotransferase-1 (GlcNAc6ST-1) failed to synthesize sulfated N-glycans and exhibited abnormal myelination and axonal degeneration in the PNS. Taken together, this study demonstrates that GlcNAc6ST-1 modulates PNS myelination and myelinated axonal survival through the GlcNAc-6-O-sulfation of N-glycans on glycoproteins. These findings may provide novel insights into the pathogenesis of peripheral neuropathy.

Chromosomal localization of murine and human oligodendrocyte-specific protein genes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bronstein, J.M.; Wu, S.; Korenberg, J.R.

1996-06-01

Oligodendrocyte-specific protein (OSP) is a recently described protein present only in myelin of the central nervous system. Several inherited disorders of myelin are caused by mutations in myelin genes but the etiology of many remain unknown. We mapped the location of the mouse OSP gene to the proximal region of chromosome 3 using two sets of multilocus crosses and to human chromosome 3 using somatic cell hybrids. Fine mapping with fluorescence in situ hybridization placed the OSP gene at human chromosome 3q26.2-q26.3. To date, there are no known inherited neurological disorders that localize to these regions. 24 refs., 2 figs.

Teleost fish as a model system to study successful regeneration of the central nervous system.

PubMed

Zupanc, Günther K H; Sîrbulescu, Ruxandra F

2013-01-01

Traumatic brain injury and spinal cord injury are devastating conditions that may result in death or long-term disability. A promising strategy for the development of effective cell replacement therapies involves the study of regeneration-competent organisms. Among this group, teleost fish are distinguished by their excellent potential to regenerate nervous tissue and to regain function after injury to the central nervous system. In this chapter, we summarize our current understanding of the cellular processes that mediate this regenerative potential, and we show that several of these processes are shared with the normal development of the intact central nervous system; we describe how the spontaneous self-repair of the teleostean central nervous system leads to functional recovery, at physiological and behavioral levels; we discuss the possible function of molecular factors associated with the degenerative and regenerative processes after injury; and, finally, we speculate on evolutionary aspects of adult neurogenesis and neuronal regeneration, and on how a better understanding of these aspects could catalyze the development of therapeutic strategies to overcome the regenerative limits of the mammalian CNS.

A different regional response by mouse oligodendrocyte progenitor cells (OPCs) to high-dose X-irradiation has consequences for repopulating OPC-depleted normal tissue.

PubMed

Irvine, Karen-Amanda; Blakemore, William F

2007-01-01

This study was designed to investigate whether the residual, dysfunctional oligodendrocyte progenitor cells (OPCs) observed following X-irradiation of the mouse spinal cord [D. M. Chari et al. (2003) Exp. Neurol., 198, 145-153], the presence of which prevented the endogenous repopulation of these areas from normal tissue, reflects a general response of OPCs in the mouse central nervous system (CNS) to X-irradiation. The brains of adult mice were exposed to 40 Gy of X-irradiation and the effect of X-irradiation on the OPCs was assessed up to 4 weeks post-irradiation using anti-NG2 antibodies. X-irradiation resulted in almost complete depletion of OPCs within the telencephalon (cortex, corpus callosum and hippocampus) by 7 days post-irradiation, which was followed by progressive repopulation of OPCs from non-irradiated areas of the cortex. By contrast, within the lower brain centres (the diencephalon and mesencephalon) OPC loss occurred much more slowly so that 26% of the OPCs still remained 4 weeks after X-irradiation. The consequence of this heterogeneous response to X-irradiation was that whereas transplanted and endogenous OPCs rapidly established themselves in the OPC-depleted telencephalon this did not occur in the areas where there was incomplete depletion of endogenous OPCs. Our findings confirm not only the requirement for almost complete OPC depletion in order to establish transplanted OPCs in normal tissue but also highlight a heterogeneity of progenitor populations in different areas of the mouse CNS.

Non-coding-regulatory regions of human brain genes delineated by bacterial artificial chromosome knock-in mice.

PubMed

Schmouth, Jean-François; Castellarin, Mauro; Laprise, Stéphanie; Banks, Kathleen G; Bonaguro, Russell J; McInerny, Simone C; Borretta, Lisa; Amirabbasi, Mahsa; Korecki, Andrea J; Portales-Casamar, Elodie; Wilson, Gary; Dreolini, Lisa; Jones, Steven J M; Wasserman, Wyeth W; Goldowitz, Daniel; Holt, Robert A; Simpson, Elizabeth M

2013-10-14

The next big challenge in human genetics is understanding the 98% of the genome that comprises non-coding DNA. Hidden in this DNA are sequences critical for gene regulation, and new experimental strategies are needed to understand the functional role of gene-regulation sequences in health and disease. In this study, we build upon our HuGX ('high-throughput human genes on the X chromosome') strategy to expand our understanding of human gene regulation in vivo. In all, ten human genes known to express in therapeutically important brain regions were chosen for study. For eight of these genes, human bacterial artificial chromosome clones were identified, retrofitted with a reporter, knocked single-copy into the Hprt locus in mouse embryonic stem cells, and mouse strains derived. Five of these human genes expressed in mouse, and all expressed in the adult brain region for which they were chosen. This defined the boundaries of the genomic DNA sufficient for brain expression, and refined our knowledge regarding the complexity of gene regulation. We also characterized for the first time the expression of human MAOA and NR2F2, two genes for which the mouse homologs have been extensively studied in the central nervous system (CNS), and AMOTL1 and NOV, for which roles in CNS have been unclear. We have demonstrated the use of the HuGX strategy to functionally delineate non-coding-regulatory regions of therapeutically important human brain genes. Our results also show that a careful investigation, using publicly available resources and bioinformatics, can lead to accurate predictions of gene expression.

Wisp2/CCN5 up-regulated in the central nervous system of GM3-only mice facilitates neurite formation in Neuro2a cells via integrin-Akt signaling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohkawa, Yuki, E-mail: tomilbio@med.nagoya-u.ac.jp; Ohmi, Yuhsuke, E-mail: ooumi82@med.nagoya-u.ac.jp; Tajima, Orie, E-mail: oriet@isc.chubu.ac.jp

Highlights: {yields} Wisp2/CCN5 was up-regulated in nervous tissues of GM3-only mutant mice. {yields} Wisp2/CCN5 was found in neurons more strongly in the mutant mice. {yields} Wisp2/CCN5 induces Akt phosphorylation via integrins and facilitates neurite formation. {yields} Wisp2/CCN5 conferred resistance to H{sub 2}O{sub 2}-induced apoptosis. {yields} Up-regulation of Wisp2/CCN5 in GM3-only mice seemed for protection of brains from neurodegeneration. -- Abstract: Wisp2/CCN5 belongs to CCN family proteins which are involved in cell proliferation, angiogenesis, tumorigenesis and wound healing. Although a number of studies on the roles of Wisp2/CCN5 in cancers have been reported, no study on the expression and function ofmore » Wisp2/CCN5 in the central nervous system has been reported. In this study, we focused on Wisp2/CCN5 that was up-regulated in nervous tissues in GM3-only mice. Over-expression of Wisp2/CCN5 enhanced neurite outgrowth potently after serum withdrawal with increased phosphorylation levels of Akt and ERKs. When cells were cultured with recombinant Wisp2/CCN5 proteins, more and longer neurites were formed than in the controls. Thus, we demonstrated for the first time that Wisp2/CCN5 facilitates neurite formation in a mouse neuroblastoma cell line, Neuro2a. Akt phosphorylation induced by recombinant Wisp2/CCN5 was suppressed after knockdown of integrin {beta}1. Moreover, Wisp2/CCN5-over-expressing cells were resistant to apoptosis induced by H{sub 2}O{sub 2}. These results suggested that secreted Wisp2/CCN5 induces Akt and ERK phosphorylation via integrins, and consequently facilitates neurite formation and conferred resistance to apoptosis. Up-regulation of Wisp2/CCN5 in GM3-only mice should be, therefore, a reaction to protect nervous tissues from neurodegeneration caused by ganglioside deficiency.« less

Mutations in spalt cause a severe but reversible neurodegenerative phenotype in the embryonic central nervous system of Drosophila melanogaster.

PubMed

Cantera, Rafael; Lüer, Karin; Rusten, Tor Erik; Barrio, Rosa; Kafatos, Fotis C; Technau, Gerhard M

2002-12-01

The gene spalt is expressed in the embryonic central nervous system of Drosophila melanogaster but its function in this tissue is still unknown. To investigate this question, we used a combination of techniques to analyse spalt mutant embryos. Electron microscopy showed that in the absence of spalt, the central nervous system cells are separated by enlarged extracellular spaces populated by membranous material at 60% of embryonic development. Surprisingly, the central nervous system from slightly older embryos (80% of development) exhibited almost wild-type morphology. An extensive survey by laser confocal microscopy revealed that the spalt mutant central nervous system has abnormal levels of particular cell adhesion and cytoskeletal proteins. Time-lapse analysis of neuronal differentiation in vitro, lineage analysis and transplantation experiments confirmed that the mutation causes cytoskeletal and adhesion defects. The data indicate that in the central nervous system, spalt operates within a regulatory pathway which influences the expression of the beta-catenin Armadillo, its ligand N-Cadherin, Notch, and the cell adhesion molecules Neuroglian, Fasciclin 2 and Fasciclin 3. Effects on the expression of these genes are persistent but many morphological aspects of the phenotype are transient, leading to the concept of sequential redundancy for stable organisation of the central nervous system.

Maximizing functional axon repair in the injured central nervous system: Lessons from neuronal development.

PubMed

Kaplan, Andrew; Bueno, Mardja; Hua, Luyang; Fournier, Alyson E

2018-01-01

The failure of damaged axons to regrow underlies disability in central nervous system injury and disease. Therapies that stimulate axon repair will be critical to restore function. Extensive axon regeneration can be induced by manipulation of oncogenes and tumor suppressors; however, it has been difficult to translate this into functional recovery in models of spinal cord injury. The current challenge is to maximize the functional integration of regenerating axons to recover motor and sensory behaviors. Insights into axonal growth and wiring during nervous system development are helping guide new approaches to boost regeneration and functional connectivity after injury in the mature nervous system. Here we discuss our current understanding of axonal behavior after injury and prospects for the development of drugs to optimize axon regeneration and functional recovery after CNS injury. Developmental Dynamics 247:18-23, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Crumbs 2 prevents cortical abnormalities in mouse dorsal telencephalon.

PubMed

Dudok, Jacobus J; Murtaza, Mariyam; Henrique Alves, C; Rashbass, Pen; Wijnholds, Jan

2016-07-01

The formation of a functionally integrated nervous system is dependent on a highly organized sequence of events that includes timely division and differentiation of progenitors. Several apical polarity proteins have been shown to play crucial roles during neurogenesis, however, the role of Crumbs 2 (CRB2) in cortical development has not previously been reported. Here, we show that conditional ablation of Crb2 in the murine dorsal telencephalon leads to defects in the maintenance of the apical complex. Furthermore, within the mutant dorsal telencephalon there is premature expression of differentiation proteins. We examined the physiological function of Crb2 on wild type genetic background as well as on background lacking Crb1. Telencephalon lacking CRB2 resulted in reduced levels of PALS1 and CRB3 from the apical complex, an increased number of mitotic cells and expanded neuronal domain. These defects are transient and therefore only result in rather mild cortical abnormalities. We show that CRB2 is required for maintenance of the apical polarity complex during development of the cortex and regulation of cell division, and that loss of CRB2 results in cortical abnormalities. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Global and 3D Spatial Assessment of Neuroinflammation in Rodent Models of Multiple Sclerosis

PubMed Central

Gupta, Shashank; Utoft, Regine; Hasseldam, Henrik; Schmidt-Christensen, Anja; Hannibal, Tine Dahlbaek; Hansen, Lisbeth; Fransén-Pettersson, Nina; Agarwal-Gupta, Noopur; Rozell, Björn; Andersson, Åsa; Holmberg, Dan

2013-01-01

Multiple Sclerosis (MS) is a progressive autoimmune inflammatory and demyelinating disease of the central nervous system (CNS). T cells play a key role in the progression of neuroinflammation in MS and also in the experimental autoimmune encephalomyelitis (EAE) animal models for the disease. A technology for quantitative and 3 dimensional (3D) spatial assessment of inflammation in this and other CNS inflammatory conditions is much needed. Here we present a procedure for 3D spatial assessment and global quantification of the development of neuroinflammation based on Optical Projection Tomography (OPT). Applying this approach to the analysis of rodent models of MS, we provide global quantitative data of the major inflammatory component as a function of the clinical course. Our data demonstrates a strong correlation between the development and progression of neuroinflammation and clinical disease in several mouse and a rat model of MS refining the information regarding the spatial dynamics of the inflammatory component in EAE. This method provides a powerful tool to investigate the effect of environmental and genetic forces and for assessing the therapeutic effects of drug therapy in animal models of MS and other neuroinflammatory/neurodegenerative disorders. PMID:24124545

Structure, production and signaling of leptin

PubMed Central

Münzberg, Heike; Morrison, Christopher D.

2014-01-01

The cloning of leptin in 1994 was an important milestone in obesity research. In those days obesity was stigmatized as a condition caused by lack of character and self-control. Mutations in either leptin or its receptor were the first single gene mutations found to cause morbid obesity, and it is now appreciated that obesity is caused by a dysregulation of central neuronal circuits. From the first discovery of the leptin deficient obese mouse (ob/ob), to the cloning of leptin (ob aka lep) and leptin receptor (db aka lepr) genes, much has been learned about leptin and its action in the central nervous system. The initial high hopes that leptin would cure obesity were quickly dampened by the discovery that most obese humans have increased leptin levels and develop leptin resistance. Nevertheless, leptin target sites in the brain represent an excellent blueprint for distinct neuronal circuits that control energy homeostasis. A better understanding of the regulation and interconnection of these circuits will further guide and improve the development of safe and effective interventions to treat obesity. This review will highlight our current knowledge about the hormone leptin, its signaling pathways and its central actions to mediate distinct physiological functions. PMID:25305050

Viral Oncolytic Therapeutics for Neoplastic Meningitis

DTIC Science & Technology

2012-07-01

the central nervous system (CNS). While several novel molecular approaches are being developed, many of them require delivery of macromolecu- lar or...nonhuman primates. Keywords PET Imaging . Pharmacokinetics . Biopharmaceuticals . Macromolecules . Brain . Central nervous system . Drug delivery...Iodine-124 Introduction The leptomeningeal route to the central nervous system (CNS) starts from drug administration (injection or in- fusion) into the

Improved distribution of small molecules and viral vectors in the murine brain using a hollow fiber catheter

PubMed Central

Seunguk, Oh; Odland, Rick; Wilson, Scott R.; Kroeger, Kurt M.; Liu, Chunyan; Lowenstein, Pedro R.; Castro, Maria G.; Hall, Walter A.; Ohlfest, John R.

2008-01-01

Object A hollow fiber catheter was developed to improve the distribution of drugs administered via direct infusion into the central nervous system (CNS). It is a porous catheter that significantly increases the surface area of brain tissue into which a drug is infused. Methods Dye was infused into the mouse brain through convection-enhanced delivery (CED) using a 28-gauge needle compared with a 3-mm-long hollow fiber catheter. To determine whether a hollow fiber catheter could increase the distribution of gene therapy vectors, a recombinant adenovirus expressing the firefly luciferase reporter was injected into the mouse striatum. Gene expression was monitored using in vivo bioluminescent imaging. To assess the distribution of gene transfer, an adenovirus expressing green fluorescent protein was injected into the striatum using a hollow fiber catheter or a needle. Results Hollow fiber catheter—mediated infusion increased the volume of brain tissue labeled with dye by 2.7 times relative to needle-mediated infusion. In vivo imaging revealed that catheter-mediated infusion of adenovirus resulted in gene expression that was 10 times greater than that mediated by a needle. The catheter appreciably increased the area of brain transduced with adenovirus relative to a needle, affecting a significant portion of the injected hemisphere. Conclusions The miniature hollow fiber catheter used in this study significantly increased the distribution of dye and adenoviral-mediated gene transfer in the mouse brain compared with the levels reached using a 28-gauge needle. Compared with standard single-port clinical catheters, the hollow fiber catheter has the advantage of millions of nanoscale pores to increase surface area and bulk flow in the CNS. Extending the scale of the hollow fiber catheter for the large mammalian brain shows promise in increasing the distribution and efficacy of gene therapy and drug therapy using CED. PMID:17886557

Inoculation of α-synuclein preformed fibrils into the mouse gastrointestinal tract induces Lewy body-like aggregates in the brainstem via the vagus nerve.

PubMed

Uemura, Norihito; Yagi, Hisashi; Uemura, Maiko T; Hatanaka, Yusuke; Yamakado, Hodaka; Takahashi, Ryosuke

2018-05-11

Intraneuronal α-synuclein (α-Syn) aggregates known as Lewy bodies (LBs) and the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) are the pathological hallmarks of Parkinson's disease (PD). Braak's hypothesis based on autopsy studies suggests that Lewy pathology initially occurs in the enteric nervous system (ENS) and then travels retrogradely to the dorsal motor nucleus of the vagus nerve (dmX), proceeding from there in a caudo-rostral direction. Recent evidence that α-Syn aggregates propagate between interconnected neurons supports this hypothesis. However, there is no direct evidence demonstrating this transmission from the ENS to the dmX and then to the SNpc. We inoculated α-Syn preformed fibrils (PFFs) or phosphate-buffered saline (PBS) into the mouse gastric wall and analyzed the progression of the pathology. The mice inoculated with α-Syn PFFs, but not with PBS, developed phosphorylated α-Syn (p-α-Syn)-positive LB-like aggregates in the dmX at 45 days postinoculation. This aggregate formation was completely abolished when vagotomy was performed prior to inoculation of α-Syn PFFs, suggesting that the aggregates in the dmX were retrogradely induced via the vagus nerve. Unexpectedly, the number of neurons containing p-α-Syn-positive aggregates in the dmX decreased over time, and no further caudo-rostral propagation beyond the dmX was observed up to 12 months postinoculation. P-α-Syn-positive aggregates were also present in the myenteric plexus at 12 months postinoculation. However, unlike in patients with PD, there was no cell-type specificity in neurons containing those aggregates in this model. These results indicate that α-Syn PFF inoculation into the mouse gastrointestinal tract can induce α-Syn pathology resembling that of very early PD, but other factors are apparently required if further progression of PD pathology is to be replicated in this animal model.

A Novel mouse model of enhanced proteostasis: Full-length human heat shock factor 1 transgenic mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Anson, E-mail: piercea2@uthscsa.edu; Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229; The Department of Veteran's Affairs, South Texas Veterans Health Care System, San Antonio, Texas, 78284

2010-11-05

Research highlights: {yields} Development of mouse overexpressing native human HSF1 in all tissues including CNS. {yields} HSF1 overexpression enhances heat shock response at whole-animal and cellular level. {yields} HSF1 overexpression protects from polyglutamine toxicity and favors aggresomes. {yields} HSF1 overexpression enhances proteostasis at the whole-animal and cellular level. -- Abstract: The heat shock response (HSR) is controlled by the master transcriptional regulator heat shock factor 1 (HSF1). HSF1 maintains proteostasis and resistance to stress through production of heat shock proteins (HSPs). No transgenic model exists that overexpresses HSF1 in tissues of the central nervous system (CNS). We generated a transgenicmore » mouse overexpressing full-length non-mutant HSF1 and observed a 2-4-fold increase in HSF1 mRNA and protein expression in all tissues studied of HSF1 transgenic (HSF1{sup +/0}) mice compared to wild type (WT) littermates, including several regions of the CNS. Basal expression of HSP70 and 90 showed only mild tissue-specific changes; however, in response to forced exercise, the skeletal muscle HSR was more elevated in HSF1{sup +/0} mice compared to WT littermates and in fibroblasts following heat shock, as indicated by levels of inducible HSP70 mRNA and protein. HSF1{sup +/0} cells elicited a significantly more robust HSR in response to expression of the 82 repeat polyglutamine-YFP fusion construct (Q82YFP) and maintained proteasome-dependent processing of Q82YFP compared to WT fibroblasts. Overexpression of HSF1 was associated with fewer, but larger Q82YFP aggregates resembling aggresomes in HSF1{sup +/0} cells, and increased viability. Therefore, our data demonstrate that tissues and cells from mice overexpressing full-length non-mutant HSF1 exhibit enhanced proteostasis.« less

Impact of Pubertal Development and Physical Activity on Heart Rate Variability in Overweight and Obese Children in Taiwan

ERIC Educational Resources Information Center

Chen, Su-Ru; Chiu, Hung-Wen; Lee, Yann-Jinn; Sheen, Tzong-Chi; Jeng, Chii

2012-01-01

Child obesity is frequently associated with dysfunction of autonomic nervous system. Children in pubertal development were suggested to be vulnerable to autonomic nervous system problems such as decrease of heart rate variability from dysregulation of metabolic control. This study explored the influence of pubertal development on autonomic nervous…

DEVELOPMENT AND MATURATION OF THE NERVOUS SYSTEM: NEUROBIOLOGICAL BASIS OF VULNERABILITY TO ENVIRONMENTAL CONTAMINANTS.

EPA Science Inventory

The susceptibility of the developing nervous system to damage following exposure to environmental contaminants is believed to be based upon the critical nature of the organizational events that occur in both a regionally- and temporally-dependent manner. The age-related susceptib...

Gallus gallus orthologous to human alpha-dystroglycanopathies candidate genes: Gene expression and characterization during chicken embryogenesis.

PubMed

Izquierdo-Lahuerta, Adriana; de Luis, Oscar; Gómez-Esquer, Francisco; Cruces, Jesús; Coloma, Antonio

2016-09-23

Alpha-dystroglycanopathies are a heterogenic group of human rare diseases that have in common defects of α-dystroglycan O-glycosylation. These congenital disorders share common features as muscular dystrophy, malformations on central nervous system and more rarely altered ocular development, as well as mutations on a set of candidate genes involved on those syndromes. Severity of the syndromes is variable, appearing Walker-Warburg as the most severe where mutations at protein O-mannosyl transferases POMT1 and POMT2 genes are frequently described. When studying the lack of MmPomt1 in mouse embryonic development, as a murine model of Walker-Warburg syndrome, MmPomt1 null phenotype was lethal because Reitchert's membrane fails during embryonic development. Here, we report gene expression from Gallus gallus orthologous genes to human candidates on alpha-dystroglycanopathies POMT1, POMT2, POMGnT1, FKTN, FKRP and LARGE, making special emphasis in expression and localization of GgPomt1. Results obtained by quantitative RT-PCR, western-blot and immunochemistry revealed close gene expression patterns among human and chicken at key tissues affected during development when suffering an alpha-dystroglycanopathy, leading us to stand chicken as a useful animal model for molecular characterization of glycosyltransferases involved in the O-glycosylation of α-Dystroglycan and its role in embryonic development. Copyright © 2016 Elsevier Inc. All rights reserved.

Novel Roles for Immune Molecules in Neural Development: Implications for Neurodevelopmental Disorders

PubMed Central

Garay, Paula A.; McAllister, A. Kimberley

2010-01-01

Although the brain has classically been considered “immune-privileged”, current research suggests an extensive communication between the immune and nervous systems in both health and disease. Recent studies demonstrate that immune molecules are present at the right place and time to modulate the development and function of the healthy and diseased central nervous system (CNS). Indeed, immune molecules play integral roles in the CNS throughout neural development, including affecting neurogenesis, neuronal migration, axon guidance, synapse formation, activity-dependent refinement of circuits, and synaptic plasticity. Moreover, the roles of individual immune molecules in the nervous system may change over development. This review focuses on the effects of immune molecules on neuronal connections in the mammalian central nervous system – specifically the roles for MHCI and its receptors, complement, and cytokines on the function, refinement, and plasticity of geniculate, cortical and hippocampal synapses, and their relationship to neurodevelopmental disorders. These functions for immune molecules during neural development suggest that they could also mediate pathological responses to chronic elevations of cytokines in neurodevelopmental disorders, including autism spectrum disorders (ASD) and schizophrenia. PMID:21423522

Age-specific function of α5β1 integrin in microglial migration during early colonization of the developing mouse cortex.

PubMed

Smolders, Sophie Marie-Thérèse; Swinnen, Nina; Kessels, Sofie; Arnauts, Kaline; Smolders, Silke; Le Bras, Barbara; Rigo, Jean-Michel; Legendre, Pascal; Brône, Bert

2017-07-01

Microglia, the immune cells of the central nervous system, take part in brain development and homeostasis. They derive from primitive myeloid progenitors that originate in the yolk sac and colonize the brain mainly through intensive migration. During development, microglial migration speed declines which suggests that their interaction with the microenvironment changes. However, the matrix-cell interactions allowing dispersion within the parenchyma are unknown. Therefore, we aimed to better characterize the migration behavior and to assess the role of matrix-integrin interactions during microglial migration in the embryonic brain ex vivo. We focused on microglia-fibronectin interactions mediated through the fibronectin receptor α5β1 integrin because in vitro work indirectly suggested a role for this ligand-receptor pair. Using 2-photon time-lapse microscopy on acute ex vivo embryonic brain slices, we found that migration occurs in a saltatory pattern and is developmentally regulated. Most importantly, there is an age-specific function of the α5β1 integrin during microglial cortex colonization. At embryonic day (E) 13.5, α5β1 facilitates migration while from E15.5, it inhibits migration. These results indicate a developmentally regulated function of α5β1 integrin in microglial migration during colonization of the embryonic brain. © 2017 Wiley Periodicals, Inc.

Slit–Robo signalling in heart development

PubMed Central

Zhao, Juanjuan; Mommersteeg, Mathilda T M

2018-01-01

Abstract The Slit ligands and their Robo receptors are well-known for their roles during axon guidance in the central nervous system but are still relatively unknown in the cardiac field. However, data from different animal models suggest a broad involvement of the pathway in many aspects of heart development, from cardiac cell migration and alignment, lumen formation, chamber formation, to the formation of the ventricular septum, semilunar and atrioventricular valves, caval veins, and pericardium. Absence of one or more of the genes in the pathway results in defects ranging from bicuspid aortic valves to ventricular septal defects and abnormal venous connections to the heart. Congenital heart defects are the most common congenital malformations found in life new-born babies and progress in methods for large scale human genetic testing has significantly enhanced the identification of new causative genes involved in human congenital heart disease. Recently, loss of function variants in ROBO1 have also been linked to ventricular septal defects and tetralogy of Fallot in patients. Here, we will give an overview of the role of the Slit–Robo signalling pathway in Drosophila, zebrafish, and mouse heart development. The extent of these data warrant further attention on the SLIT–ROBO signalling pathway as a candidate for an array of human congenital heart defects. PMID:29538649

A mouse model for fucosidosis recapitulates storage pathology and neurological features of the milder form of the human disease

PubMed Central

Wolf, Heike; Stroobants, Stijn; D'Hooge, Rudi; Hermans-Borgmeyer, Irm; Lüllmann-Rauch, Renate; Dierks, Thomas; Lübke, Torben

2016-01-01

ABSTRACT Fucosidosis is a rare lysosomal storage disorder caused by the inherited deficiency of the lysosomal hydrolase α-L-fucosidase, which leads to an impaired degradation of fucosylated glycoconjugates. Here, we report the generation of a fucosidosis mouse model, in which the gene for lysosomal α-L-fucosidase (Fuca1) was disrupted by gene targeting. Homozygous knockout mice completely lack α-L-fucosidase activity in all tested organs leading to highly elevated amounts of the core-fucosylated glycoasparagine Fuc(α1,6)-GlcNAc(β1-N)-Asn and, to a lesser extent, other fucosylated glycoasparagines, which all were also partially excreted in urine. Lysosomal storage pathology was observed in many visceral organs, such as in the liver, kidney, spleen and bladder, as well as in the central nervous system (CNS). On the cellular level, storage was characterized by membrane-limited cytoplasmic vacuoles primarily containing water-soluble storage material. In the CNS, cellular alterations included enlargement of the lysosomal compartment in various cell types, accumulation of secondary storage material and neuroinflammation, as well as a progressive loss of Purkinje cells combined with astrogliosis leading to psychomotor and memory deficits. Our results demonstrate that this new fucosidosis mouse model resembles the human disease and thus will help to unravel underlying pathological processes. Moreover, this model could be utilized to establish diagnostic and therapeutic strategies for fucosidosis. PMID:27491075

17β-Estradiol Promotes Schwann Cell Proliferation and Differentiation, Accelerating Early Remyelination in a Mouse Peripheral Nerve Injury Model

PubMed Central

Chen, Yan; Guo, Wenjie; Li, Wenjuan; Cheng, Meng; Hu, Ying; Xu, Wenming

2016-01-01

Estrogen induces oligodendrocyte remyelination in response to demyelination in the central nervous system. Our objective was to determine the effects of 17β-estradiol (E2) on Schwann cell function and peripheral nerve remyelination after injury. Adult male C57BL/6J mice were used to prepare the sciatic nerve transection injury model and were randomly categorized into control and E2 groups. To study myelination in vitro, dorsal root ganglion (DRG) explant culture was prepared using 13.5-day-old mouse embryos. Primary Schwann cells were isolated from the sciatic nerves of 1- to 3-day-old Sprague–Dawley rats. Immunostaining for myelin basic protein (MBP) expression and toluidine blue staining for myelin sheaths demonstrated that E2 treatment accelerates early remyelination in the “nerve bridge” region between the proximal and distal stumps of the transection injury site in the mouse sciatic nerve. The 5-bromo-2′-deoxyuridine incorporation assay revealed that E2 promotes Schwann cell proliferation in the bridge region and in the primary culture, which is blocked using AKT inhibitor MK2206. The in vitro myelination in the DRG explant culture determined showed that the MBP expression in the E2-treated group is higher than that in the control group. These results show that E2 promotes Schwann cell proliferation and myelination depending on AKT activation. PMID:27872858

Fingolimod: A Disease-Modifier Drug in a Mouse Model of Amyotrophic Lateral Sclerosis.

PubMed

Potenza, Rosa Luisa; De Simone, Roberta; Armida, Monica; Mazziotti, Valentina; Pèzzola, Antonella; Popoli, Patrizia; Minghetti, Luisa

2016-10-01

Fingolimod phosphate (FTY720), the first approved oral therapy for multiple sclerosis, primarily acts as an immunomodulator. Its concomitant effects in the central nervous system, however, indicate a potentially broader spectrum of activity in neurodegenerative diseases. In the present study, we investigated the possible effects of fingolimod in a mouse model of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by a strong neuroinflammatory component. Fingolimod (0.1 and 1 mg/kg i.p.) was administered to mSOD1 G93A mice, a well-characterized mouse model of ALS, starting from the onset of motor symptoms to the end stage of the disease. The drug was able to improve the neurological phenotype (p < 0.05) and to extend the survival (p < 0.01) of ALS mice. The beneficial effect of fingolimod administration was associated with a significant modulation of neuroinflammatory and protective genes (CD11b, Foxp3, iNOS, Il1β, Il10, Arg1, and Bdnf) in motor cortex and spinal cord of animals. Our data show, for the first time, that fingolimod is protective in ALS mice and that its beneficial effects are accompanied by a modulation of microglial activation and innate immunity. Considering that the treatment was started in already symptomatic mice, our data strongly support fingolimod as a potential new therapeutic approach to ALS.

Intermittent fasting alleviates the neuropathic phenotype in a mouse model of Charcot-Marie-Tooth disease

PubMed Central

Madorsky, Irina; Opalach, Katherine; Waber, Amanda; Verrier, Jonathan D.; Solmo, Chelsea; Foster, Thomas; Dunn, William A; Notterpek, Lucia

2009-01-01

Charcot-Marie-Tooth type 1A (CMT1A) neuropathies linked to the misexpression of peripheral myelin protein 22 (PMP22) are progressive demyelinating disorders of the peripheral nervous system. In this study we asked whether dietary restriction by intermittent fasting (IF) could alleviate the neuropathic phenotype in the Trembler J (TrJ) mouse model of CMT1A. Our results show that neuropathic mice kept on a five month long IF regimen had improved locomotor performance compared to ad libitum (AL) fed littermates. The functional benefits of this dietary intervention are associated with an increased expression of myelin proteins combined with a thicker myelin sheath, less redundant basal lamina, and a reduction in aberrant Schwann cell proliferation. These morphological improvements are accompanied by a decrease in PMP22 protein aggregates, and enhanced expression of cytosolic chaperones and constituents of the autophagy-lysosomal pathway. These results indicate that dietary restriction is beneficial for peripheral nerve function in TrJ neuropathic mice, as it promotes the maintenance of locomotor performance. PMID:19320048

Proposal of a model of mammalian neural induction

PubMed Central

Levine, Ariel J.; Brivanlou, Ali H.

2009-01-01

How does the vertebrate embryo make a nervous system? This complex question has been at the center of developmental biology for many years. The earliest step in this process – the induction of neural tissue – is intimately linked to patterning of the entire early embryo, and the molecular and embryological basis these processes are beginning to emerge. Here, we analyze classic and cutting-edge findings on neural induction in the mouse. We find that data from genetics, tissue explants, tissue grafting, and molecular marker expression support a coherent framework for mammalian neural induction. In this model, the gastrula organizer of the mouse embryo inhibits BMP signaling to allow neural tissue to form as a default fate – in the absence of instructive signals. The first neural tissue induced is anterior and subsequent neural tissue is posteriorized to form the midbrain, hindbrain, and spinal cord. The anterior visceral endoderm protects the pre-specified anterior neural fate from similar posteriorization, allowing formation of forebrain. This model is very similar to the default model of neural induction in the frog, thus bridging the evolutionary gap between amphibians and mammals. PMID:17585896

Long term effects of low doses of Fe-56 ions on the brain and retina of the mouse - Ultrastructural and behavioral studies

NASA Technical Reports Server (NTRS)

Philpott, Delbert E.; Miquel, Jaime

1986-01-01

Eight-month-old male C57BL6 mice were exposed without anesthesia to whole-body irradiation in circular holders. The mice were tested for behavioral decrements after 0.5 and 50 rads of Fe particle irradiation at 6 and 12 months postirradiation to obtain long-term results. A standard maze was used, and the animals were timed for completion thereof. A string test also was administered to the mice, testing their ability to grasp and move along a string to safety. The results from animals exposed to 50 rads were significantly different from control results to p = less than 0.001 in both systems of testing. The hippocampus (believed to be the location of environmental interaction in the brain) and the retina were examined for ultrastructural changes. The ultrastructural changes were similar to those found in the Cosmos 782, 936, and Argon experiments. The mouse data indicate that iron particles were able to induce long-term changes in the central nervous system which led to behavioral impairment.

HSV-1 interaction to 3-O-sulfated heparan sulfate in mouse-derived DRG explant and profiles of inflammatory markers during virus infection.

PubMed

Sharthiya, Harsh; Seng, Chanmoly; Van Kuppevelt, T H; Tiwari, Vaibhav; Fornaro, Michele

2017-06-01

The molecular mechanism of herpes simplex virus (HSV) entry and the associated inflammatory response in the nervous system remain poorly understood. Using mouse-derived ex vivo dorsal root ganglia (DRG) explant model and single cell neurons (SCNs), in this study, we provided a visual evidence for the expression of heparan sulfate (HS) and 3-O-sulfated heparan sulfate (3-OS HS) followed by their interactions with HSV-1 glycoprotein B (gB) and glycoprotein D (gD) during cell entry. Upon heparanase treatment of DRG-derived SCN, a significant inhibition of HSV-1 entry was observed suggesting the involvement of HS role during viral entry. Finally, a cytokine array profile generated during HSV-1 infection in DRG explant indicated an enhanced expression of chemokines (LIX, TIMP-2, and M-CSF)-known regulators of HS. Taken together, these results highlight the significance of HS during HSV-1 entry in DRG explant. Further investigation is needed to understand which isoforms of 3-O-sulfotransferase (3-OST)-generated HS contributed during HSV-1 infection and associated cell damage.

Neuronal calcium sensor-1 deletion in the mouse decreases motivation and dopamine release in the nucleus accumbens.

PubMed

Ng, Enoch; Varaschin, Rafael K; Su, Ping; Browne, Caleb J; Hermainski, Joanna; Le Foll, Bernard; Pongs, Olaf; Liu, Fang; Trudeau, Louis-Eric; Roder, John C; Wong, Albert H C

2016-03-15

Calcium sensors detect intracellular calcium changes and interact with downstream targets to regulate many functions. Neuronal Calcium Sensor-1 (NCS-1) or Frequenin is widely expressed in the nervous system, and involved in neurotransmission, synaptic plasticity and learning. NCS-1 interacts with and regulates dopamine D2 receptor (D2R) internalization and is implicated in disorders like schizophrenia and substance abuse. However, the role of NCS-1 in behaviors dependent on dopamine signaling in the striatum, where D2R is most highly expressed, is unknown. We show that Ncs-1 deletion in the mouse decreases willingness to work for food. Moreover, Ncs-1 knockout mice have significantly lower activity-dependent dopamine release in the nucleus accumbens core in acute slice recordings. In contrast, food preference, responding for conditioned reinforcement, ability to represent changes in reward value, and locomotor response to amphetamine are not impaired. These studies identify novel roles for NCS-1 in regulating activity-dependent striatal dopamine release and aspects of motivated behavior. Copyright © 2015 Elsevier B.V. All rights reserved.

PW1 gene/paternally expressed gene 3 (PW1/Peg3) identifies multiple adult stem and progenitor cell populations

PubMed Central

Besson, Vanessa; Smeriglio, Piera; Wegener, Amélie; Relaix, Frédéric; Nait Oumesmar, Brahim; Sassoon, David A.; Marazzi, Giovanna

2011-01-01

A variety of markers are invaluable for identifying and purifying stem/progenitor cells. Here we report the generation of a murine reporter line driven by Pw1 that reveals cycling and quiescent progenitor/stem cells in all adult tissues thus far examined, including the intestine, blood, testis, central nervous system, bone, skeletal muscle, and skin. Neurospheres generated from the adult PW1-reporter mouse show near 100% reporter-gene expression following a single passage. Furthermore, epidermal stem cells can be purified solely on the basis of reporter-gene expression. These cells are clonogenic, repopulate the epidermal stem-cell niches, and give rise to new hair follicles. Finally, we demonstrate that only PW1 reporter-expressing epidermal cells give rise to follicles that are capable of self-renewal following injury. Our data demonstrate that PW1 serves as an invaluable marker for competent self-renewing stem cells in a wide array of adult tissues, and the PW1-reporter mouse serves as a tool for rapid stem cell isolation and characterization. PMID:21709251

Central insulin dysregulation and energy dyshomeostasis in two mouse models of Alzheimer's disease.

PubMed

Velazquez, Ramon; Tran, An; Ishimwe, Egide; Denner, Larry; Dave, Nikhil; Oddo, Salvatore; Dineley, Kelly T

2017-10-01

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder worldwide. While the causes of AD are not known, several risk factors have been identified. Among these, type two diabetes (T2D), a chronic metabolic disease, is one of the most prevalent risk factors for AD. Insulin resistance, which is associated with T2D, is defined as diminished or absent insulin signaling and is reflected by peripheral blood hyperglycemia and impaired glucose clearance. In this study, we used complementary approaches to probe for peripheral insulin resistance, central nervous system (CNS) insulin sensitivity and energy homeostasis in Tg2576 and 3xTg-AD mice, two widely used animal models of AD. We report that CNS insulin signaling abnormalities are evident months before peripheral insulin resistance. In addition, we find that brain energy metabolism is differentially altered in both mouse models, with 3xTg-AD mice showing more extensive changes. Collectively, our data suggest that early AD may reflect engagement of different signaling networks that influence CNS metabolism, which in turn may alter peripheral insulin signaling. Copyright © 2017 Elsevier Inc. All rights reserved.

CNS infiltration of peripheral immune cells: D-Day for neurodegenerative disease?

PubMed

Rezai-Zadeh, Kavon; Gate, David; Town, Terrence

2009-12-01

While the central nervous system (CNS) was once thought to be excluded from surveillance by immune cells, a concept known as "immune privilege," it is now clear that immune responses do occur in the CNS-giving rise to the field of neuroimmunology. These CNS immune responses can be driven by endogenous (glial) and/or exogenous (peripheral leukocyte) sources and can serve either productive or pathological roles. Recent evidence from mouse models supports the notion that infiltration of peripheral monocytes/macrophages limits progression of Alzheimer's disease pathology and militates against West Nile virus encephalitis. In addition, infiltrating T lymphocytes may help spare neuronal loss in models of amyotrophic lateral sclerosis. On the other hand, CNS leukocyte penetration drives experimental autoimmune encephalomyelitis (a mouse model for the human demyelinating disease multiple sclerosis) and may also be pathological in both Parkinson's disease and human immunodeficiency virus encephalitis. A critical understanding of the cellular and molecular mechanisms responsible for trafficking of immune cells from the periphery into the diseased CNS will be key to target these cells for therapeutic intervention in neurodegenerative diseases, thereby allowing neuroregenerative processes to ensue.

Phosphatidylserine Ameliorates Neurodegenerative Symptoms and Enhances Axonal Transport in a Mouse Model of Familial Dysautonomia

PubMed Central

Naftelberg, Shiran; Abramovitch, Ziv; Gluska, Shani; Yannai, Sivan; Joshi, Yuvraj; Donyo, Maya; Ben-Yaakov, Keren; Gradus, Tal; Zonszain, Jonathan; Farhy, Chen; Ashery-Padan, Ruth

2016-01-01

Familial Dysautonomia (FD) is a neurodegenerative disease in which aberrant tissue-specific splicing of IKBKAP exon 20 leads to reduction of IKAP protein levels in neuronal tissues. Here we generated a conditional knockout (CKO) mouse in which exon 20 of IKBKAP is deleted in the nervous system. The CKO FD mice exhibit developmental delays, sensory abnormalities, and less organized dorsal root ganglia (DRGs) with attenuated axons compared to wild-type mice. Furthermore, the CKO FD DRGs show elevated HDAC6 levels, reduced acetylated α-tubulin, unstable microtubules, and impairment of axonal retrograde transport of nerve growth factor (NGF). These abnormalities in DRG properties underlie neuronal degeneration and FD symptoms. Phosphatidylserine treatment decreased HDAC6 levels and thus increased acetylation of α-tubulin. Further PS treatment resulted in recovery of axonal outgrowth and enhanced retrograde axonal transport by decreasing histone deacetylase 6 (HDAC6) levels and thus increasing acetylation of α-tubulin levels. Thus, we have identified the molecular pathway that leads to neurodegeneration in FD and have demonstrated that phosphatidylserine treatment has the potential to slow progression of neurodegeneration. PMID:27997532

Phosphatidylserine Ameliorates Neurodegenerative Symptoms and Enhances Axonal Transport in a Mouse Model of Familial Dysautonomia.

PubMed

Naftelberg, Shiran; Abramovitch, Ziv; Gluska, Shani; Yannai, Sivan; Joshi, Yuvraj; Donyo, Maya; Ben-Yaakov, Keren; Gradus, Tal; Zonszain, Jonathan; Farhy, Chen; Ashery-Padan, Ruth; Perlson, Eran; Ast, Gil

2016-12-01

Familial Dysautonomia (FD) is a neurodegenerative disease in which aberrant tissue-specific splicing of IKBKAP exon 20 leads to reduction of IKAP protein levels in neuronal tissues. Here we generated a conditional knockout (CKO) mouse in which exon 20 of IKBKAP is deleted in the nervous system. The CKO FD mice exhibit developmental delays, sensory abnormalities, and less organized dorsal root ganglia (DRGs) with attenuated axons compared to wild-type mice. Furthermore, the CKO FD DRGs show elevated HDAC6 levels, reduced acetylated α-tubulin, unstable microtubules, and impairment of axonal retrograde transport of nerve growth factor (NGF). These abnormalities in DRG properties underlie neuronal degeneration and FD symptoms. Phosphatidylserine treatment decreased HDAC6 levels and thus increased acetylation of α-tubulin. Further PS treatment resulted in recovery of axonal outgrowth and enhanced retrograde axonal transport by decreasing histone deacetylase 6 (HDAC6) levels and thus increasing acetylation of α-tubulin levels. Thus, we have identified the molecular pathway that leads to neurodegeneration in FD and have demonstrated that phosphatidylserine treatment has the potential to slow progression of neurodegeneration.

Long term effects of low doses of 56Fe ions on the brain and retina of the mouse: ultrastructural and behavioral studies

NASA Technical Reports Server (NTRS)

Philpott, D. E.; Miquel, J.

1986-01-01

Eight month old male C57BL6 mice were exposed without anesthesia to whole-body irradiation in circular holders. The mice were tested for behavioral decrements after 0.5 and 50 rads of Fe particle irradiation at 6 and 12 months post irradiation to obtain long term results. A standard maze was used and the animals were timed for completion thereof. A string test also was administered to the mice, testing their ability to grasp and move along a string to safety. The results from animals exposed to 50 rads were significantly different from [correction of fron] control results to p = < .001 in both systems of testing. The hippocampus (believed to be the location of environmental interaction in the brain) and the retina were examined for ultrastructural changes. The ultrastructural changes were similar to those we found in our Cosmos 782, 936 and in our Argon experiments. The mouse data indicate that iron particles were able to induce long term changes in the central nervous system which lead to behavioral impairment.

Differential splicing generates a nervous system-specific form of Drosophila neuroglian.

PubMed

Hortsch, M; Bieber, A J; Patel, N H; Goodman, C S

1990-05-01

We recently described the characterization and cloning of Drosophila neuroglian, a member of the immunoglobulin superfamily. Neuroglian contains six immunoglobulin-like domains and five fibronectin type III domains and shows strong sequence homology to the mouse neural cell adhesion molecule L1. Here we show that the neuroglian gene generates at least two different protein products by tissue-specific alternative splicing. The two protein forms differ in their cytoplasmic domains. The long form is restricted to the surface of neurons in the CNS and neurons and some support cells in the PNS; in contrast, the short form is expressed on a wide range of other cells and tissues. Thus, whereas the mouse L1 gene appears to encode only one protein that functions largely as a neural cell adhesion molecule, its Drosophila homolog, the neuroglian gene, encodes at least two protein forms that may play two different roles, one as a neural cell adhesion molecule and the other as a more general cell adhesion molecule involved in other tissues and imaginal disc morphogenesis.

Classification of neural tumors in laboratory rodents, emphasizing the rat.

PubMed

Weber, Klaus; Garman, Robert H; Germann, Paul-Georg; Hardisty, Jerry F; Krinke, Georg; Millar, Peter; Pardo, Ingrid D

2011-01-01

Neoplasms of the nervous system, whether spontaneous or induced, are infrequent in laboratory rodents and very rare in other laboratory animal species. The morphology of neural tumors depends on the intrinsic functions and properties of the cell type, the interactions between the neoplasm and surrounding normal tissue, and regressive changes. The incidence of neural neoplasms varies with sex, location, and age of tumor onset. Although the onset of spontaneous tumor development cannot be established in routine oncogenicity studies, calculations using the time of diagnosis (day of death) have revealed significant differences in tumor biology among different rat strains. In the central nervous system, granular cell tumors (a meningioma variant), followed by glial tumors, are the most common neoplasms in rats, whereas glial cell tumors are observed most frequently in mice. Central nervous system tumors usually affect the brain rather than the spinal cord. Other than adrenal gland pheochromocytomas, the most common neoplasms of the peripheral nervous system are schwannomas. Neural tumors may develop in the central nervous system and peripheral nervous system from other cell lineages (including extraneural elements like adipose tissue and lymphocytes), but such lesions are very rare in laboratory animals.

Cell Signaling and Neurotoxicity: Protein Kinase C in vitro and in vivo

EPA Science Inventory

There is a growing concern about the effects of chemicals on the developing nervous system. Chemical exposure at critical periods of development can be associated with effects ranging from subtle to profound on the structure and/or function of the nervous system. Understanding cr...

Neurogenic Communication Disorders and Paralleling Agraphic Disturbances: Implications for Concerns in Basic Writing.

ERIC Educational Resources Information Center

De Jarnette, Glenda

Vertical and lateral integration are two important nervous system integrations that affect the development of oral behaviors. There are three progressions in the vertical integration process for speech nervous system development: R-complex speech (ritualistic, memorized expressions), limbic speech (emotional expressions), and cortical speech…

The proof-of-concept of ASS234: Peripherally administered ASS234 enters the central nervous system and reduces pathology in a male mouse model of Alzheimer disease

PubMed Central

Serrano, Mari Paz; Herrero-Labrador, Raquel; Futch, Hunter S.; Serrano, Julia; Romero, Alejandro; Fernandez, Ana Patricia; Samadi, Abdelouahid; Unzeta, Mercedes; Marco-Contelles, Jose; Martínez-Murillo, Ricardo

2017-01-01

Background The heterogeneity of Alzheimer disease requires the development of multitarget drugs for treating the symptoms of the disease and its progression. Both cholinergic and monoamine oxidase dysfunctions are involved in the pathological process. Thus, we hypothesized that the development of therapies focused on these targets might be effective. We have developed and assessed a new product, coded ASS234, a multipotent acetyl and butyrylcholinesterase/monoamine oxidase A–B inhibitor with a potent inhibitory effect on amyloid-β aggregation as well as antioxidant and antiapoptotic properties. But there is a need to reliably correlate in vitro and in vivo drug release data. Methods We examined the effect of ASS234 on cognition in healthy adult C57BL/6J mice in a model of scopolamine-induced cognitive impairment that often accompanies normal and pathological aging. Also, in a characterized transgenic APPswe/PS1ΔE9 mouse model of Alzheimer disease, we examined the effects of short-term ASS234 treatment on plaque deposition and gliosis using immunohistochemistry. Toxicology of ASS234 was assessed using a quantitative high-throughput in vitro cytotoxicity screening assay following the MTT assay method in HepG2 liver cells. Results In vivo, ASS234 significantly decreased scopolamine-induced learning deficits in C57BL/6J mice. Also, reduction of amyloid plaque burden and gliosis in the cortex and hippocampus was assessed. In vitro, ASS234 exhibited lesser toxicity than donepezil and tacrine. Limitations The study was conducted in male mice only. Although the Alzheimer disease model does not recapitulate all features of the human disease, it exhibits progressive monoaminergic neurodegeneration. Conclusion ASS234 is a promising alternative drug of choice to treat the cognitive decline and neurodegeneration underlying Alzheimer disease. PMID:27636528

Development and validation of a specific and sensitive HPLC-ESI-MS method for quantification of lysophosphatidylinositols and evaluation of their levels in mice tissues.

PubMed

Masquelier, Julien; Muccioli, Giulio G

2016-07-15

Increasing evidence suggests that lysophosphatidylinositols (LPIs), a subspecies of lysophospholipids, are important endogenous mediators. Although LPIs long remained among the less studied lysophospholipids, the identification of GPR55 as their molecular target sparked a renewed interest in the study of these bioactive lipids. Furthermore, increasing evidence points towards a role for LPIs in cancer development. However, a better understanding of the role and functions of LPIs in physiology and disease requires methods that allow for the quantification of LPI levels in cells and tissues. Because dedicated efficient methods for quantifying LPIs were missing, we decided to develop and validate an HPLC-ESI-MS method for the quantification of LPI species from tissues. LPIs are extracted from tissues by liquid/liquid extraction, pre-purified by solid-phase extraction, and finally analyzed by HPLC-ESI-MS. We determined the method's specificity and selectivity, we established calibration curves, determined the carry over (< 2%), LOD and LLOQ (between 0.116-7.82 and 4.62-92.5pmol on column, respectively), linearity (0.988 80%), intermediate precision (CV<20%) as well as the recovery from tissues. We then applied the method to determine the relative abundance of the LPI species in 15 different mouse tissues. Finally, we quantified the absolute LPI levels in six different mouse tissues. We found that while 18:0 LPI represents more than 60% of all the LPI species in the periphery (e.g. liver, gastrointestinal tract, lungs, spleen) it is much less abundant in the central nervous system where the levels of 20:4 LPI are significantly higher. Thus this validated HPLC-ESI-MS method for quantifying LPIs represents a powerful tool that will facilitate the comprehension of the pathophysiological roles of LPIs. Copyright © 2016 Elsevier B.V. All rights reserved.

Rivastigmine

MedlinePlus

... in people with Parkinson's disease (a brain and nervous system disease with symptoms of slowing of movement, muscle ... develops abnormal protein structures, and the brain and nervous system are destroyed over time). Talk to your doctor ...

Radiation Injury to the Brain

MedlinePlus

... healthy cells. The Merck Manual states the following: Radiation Injury to the Nervous System: The nervous system can be damaged by radiation therapy. Acute and subacute transient symptoms may develop early, but ...

THE ROLE OF ANDROGENS AND ESTROGENS IN THE DEVELOPMENT OF BRAIN AND PERIPHERAL NERVOUS SYSTEM: APPROACHES TO DEVELOPING ANIMAL MODELS FOR SEXUALLY DIMORPHIC BEHAVIORS

EPA Science Inventory

This presentation provides an overview of research on the effects of hormonally active chemicals on sexual differentiation of the brain including (a) research on the role of androgens and estrogens in the development of the brain and peripheral nervous system, (b) approaches to d...

Effect of Urtica dioica on memory dysfunction and hypoalgesia in an experimental model of diabetic neuropathy.

PubMed

Patel, Sita Sharan; Udayabanu, M

2013-09-27

Diabetic neuropathy is considered as a disease of the peripheral nervous system, but recent evidences suggest the involvement of central nervous system as well. In this study we evaluated the effect of Urtica dioica (UD) extract against memory dysfunction and hypoalgesia on a mouse model of streptozotocin (STZ) induced diabetic neuropathy. STZ (50 mg/kg, i.p. consecutively for 5 days) was used to induce diabetes, followed by treatment with the UD extract (50 mg/kg, oral) and rosiglitazone (5 mg/kg, oral) for 8 weeks. Cognitive functions were evaluated using Morris water maze and passive avoidance step through task. Pain thresholds were measured using thermal, mechanical and chemical induced hyperalgesia. We observed that chronic diabetes resulted in a decline in circulating insulin level, elevated blood glucose, reduced body weight, increased water intake, cognitive impairment and hypoalgesia. UD significantly reduced the blood glucose and polydypsia, as well as improved the body weight, insulin level, cognition and insensate neuropathy. In conclusion, UD showed results comparable to rosiglitazone in reversing the long standing diabetes induced complications such as central and peripheral neuronal dysfunction. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Effects of fenoterol on the skeletal system depend on the androgen level.

PubMed

Śliwiński, Leszek; Cegieła, Urszula; Pytlik, Maria; Folwarczna, Joanna; Janas, Aleksandra; Zbrojkiewicz, Małgorzata

2017-04-01

The role of sympathetic nervous system in the osseous tissue remodeling is not clear enough. The effects of fenoterol, a selective β 2 -adrenomimetic drug, on the skeletal system of normal and androgen deficient (orchidectomized) rats were studied in vivo. Osteoclastogenesis and mRNA expression in osteoblasts were investigated in vitro in mouse cell cultures. Fenoterol administered to animals with physiological androgen level unfavorably affected the skeletal system, damaging the bone microarchitecture. Androgen deficiency induced osteoporotic changes, and fenoterol protected the osseous tissue from consequences of androgen deficiency. The results of in vitro studies correlated with the in vivo observations. A significantly increased number of osteoclasts in bone marrow cell cultures to which testosterone and fenoterol were added simultaneously was demonstrated. In cultures without the addition of testosterone, fenoterol significantly inhibited osteoclastogenesis in comparison with control cultures. The results indicate the favorable action of fenoterol in conditions of testosterone deficiency, and its destructive influence upon the skeleton in the presence of androgens. The results confirm the key role of sympathetic nervous system in the regulation of bone remodeling. Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.

Innate immunity in the pathogenesis of polytropic retrovirus infection in the central nervous system.

PubMed

Peterson, Karin E; Du, Min

2009-01-01

Neuroinflammation, including astrogliosis, microgliosis, and the production of proinflammatory cytokines and chemokines is a common response in the central nervous system (CNS) to virus infection, including retrovirus infection. However, the contribution of this innate immune response in disease pathogenesis remains unresolved. Analysis of the neuroinflammatory response to polytropic retrovirus infection in the mouse has provided insight into the potential contribution of the innate immune response to retrovirus-induced neurologic disease. In this model, retroviral pathogenesis correlates with the induction of neuroinflammatory responses including the activation of astrocytes and microglia, as well as the production of proinflammatory cytokines and chemokines. Studies of the neurovirulent determinants of the polytropic envelope protein as well as studies with knockout mice suggest that retroviral pathogenesis in the brain is multifaceted and that cytokine and chemokine production may be only one mechanism of disease pathogenesis. Analysis of the activation of the innate immune response to retrovirus infection in the CNS indicates that toll-like receptor 7 (TLR7) is a contributing factor to retrovirus-induced neuroinflammation, but that other factors can compensate for the lack of TLR7 in inducing both neuroinflammation and neurologic disease.

Proteomic identification of aldolase A as an autoantibody target in patients with atypical movement disorders.

PubMed

Privitera, Daniela; Corti, Valeria; Alessio, Massimo; Volontè, Maria Antonietta; Volontè, Antonietta; Lampasona, Vito; Comi, Giancarlo; Martino, Gianvito; Franciotta, Diego; Furlan, Roberto; Fazio, Raffaella

2013-03-01

We tried to identify the target/s of autoantibodies to basal ganglia neurons found in a patient with hyperkinetic movement disorders (HMD) characterized by rapid, rhythmic involuntary movements or spasms in both face and neck. Patient and control sera were used in Western blot to probe mouse brain homogenates. Two-dimensional gel electrophoresis (2-DE) SDS-PAGE protein spots recognized by the patient's antibodies were excised and sequenced by mass spectrometry analysis, and the glycolytic enzyme aldolase A was identified as the antigen recognized by the patient's autoantibodies. To assess relevance and specificity of these antibodies to the identified targets as biomarkers of autoimmunity in movement disorders, autoantibody responses to the identified target were then measured by ELISA in various diseases of the central nervous system. Anti-aldolase A autoantibodies were associated mainly with HMD (7/17, 41%) and Parkinson's disease (4/30, 13%) patients, and undetectable in subjects with other inflammatory and non-inflammatory central nervous system diseases. We, thus, identified aldolase A as an autoantigen in a sub-group of patients with HMD, a clinically ill-defined syndrome. Anti-aldolase A antibodies may represent a useful biomarker of autoimmunity in HMD patients.

Pathobiology of Christianson Syndrome: Linking Disrupted Endosomal-Lysosomal Function with Intellectual Disability and Sensory Impairments.

PubMed

Kerner-Rossi, Mallory; Gulinello, Maria; Walkley, Steven; Dobrenis, Kostantin

2018-05-14

Christianson syndrome (CS) is a recently described rare neurogenetic disorder presenting early in life with a broad range of neurological symptoms, including severe intellectual disability with nonverbal status, hyperactivity, epilepsy, and progressive ataxia due to cerebellar atrophy. CS is due to loss-of-function mutations in SLC9A6, encoding NHE6, a sodium-hydrogen exchanger involved in the regulation of early endosomal pH. Here we review what is currently known about the neuropathogenesis of CS, based on insights from experimental models, which to date have focused on mechanisms that affect the CNS, specifically the brain. In addition, parental reports of sensory disturbances in their children with CS, including an apparent insensitivity to pain, led us to explore sensory function and related neuropathology in Slc9a6 KO mice. We present new data showing sensory deficits in Slc9a6 KO mice, which had reduced behavioral responses to noxious thermal and mechanical stimuli (Hargreaves and Von Frey assays, respectively) compared to wild type (WT) littermates. Immunohistochemical and ultrastructural analysis of the spinal cord and peripheral nervous system revealed intracellular accumulation of the glycosphingolipid GM2 ganglioside in KO but not WT mice. This cellular storage phenotype was most abundant in neurons of lamina I-II of the dorsal horn, a major relay site in the processing of painful stimuli. Spinal cords of KO mice also exhibited changes in astroglial and microglial populations throughout the gray matter suggestive of a neuroinflammatory process. Our findings establish the Slc9a6 KO mouse as a relevant tool for studying the sensory deficits in CS, and highlight selective vulnerabilities in relevant cell populations that may contribute to this phenotype. How NHE6 loss of function leads to such a multifaceted neurological syndrome is still undefined, and it is likely that NHE6 is involved with many cellular processes critical to normal nervous system development and function. In addition, the sensory issues exhibited by Slc9a6 KO mice, in combination with our neuropathological findings, are consistent with NHE6 loss of function impacting the entire nervous system. Sensory dysfunction in intellectually disabled individuals is challenging to assess and may impair patient safety and quality of life. Further mechanistic studies of the neurological impairments underlying CS and other genetic intellectual disability disorders must also take into account mechanisms affecting broader nervous system function in order to understand the full range of associated disabilities. Copyright © 2018. Published by Elsevier Inc.

Advances in natural biomaterials for nerve tissue repair.

PubMed

Khaing, Zin Z; Schmidt, Christine E

2012-06-25

Natural biomaterials are well positioned to play a significant role in the development of the next generation of biomaterials for nervous system repair. These materials are derived from naturally occurring substances and are highly diverse and versatile. They are generally biocompatible and are well tolerated in vivo, and therefore have a high potential to be successful as part of clinical repair strategies in the nervous system. Here we review recent reports on acellular tissue grafts, collagen, hyaluronan, fibrin, and agarose in their use to repair the nervous system. In addition, newly developed advanced fabrication techniques to further develop the next generation natural biomaterials-based therapeutic devices are discussed. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Genomic analysis of wig-1 pathways.

PubMed

Sedaghat, Yalda; Mazur, Curt; Sabripour, Mahyar; Hung, Gene; Monia, Brett P

2012-01-01

Wig-1 is a transcription factor regulated by p53 that can interact with hnRNP A2/B1, RNA Helicase A, and dsRNAs, which plays an important role in RNA and protein stabilization. in vitro studies have shown that wig-1 binds p53 mRNA and stabilizes it by protecting it from deadenylation. Furthermore, p53 has been implicated as a causal factor in neurodegenerative diseases based in part on its selective regulatory function on gene expression, including genes which, in turn, also possess regulatory functions on gene expression. In this study we focused on the wig-1 transcription factor as a downstream p53 regulated gene and characterized the effects of wig-1 down regulation on gene expression in mouse liver and brain. Antisense oligonucleotides (ASOs) were identified that specifically target mouse wig-1 mRNA and produce a dose-dependent reduction in wig-1 mRNA levels in cell culture. These wig-1 ASOs produced marked reductions in wig-1 levels in liver following intraperitoneal administration and in brain tissue following ASO administration through a single striatal bolus injection in FVB and BACHD mice. Wig-1 suppression was well tolerated and resulted in the reduction of mutant Htt protein levels in BACHD mouse brain but had no effect on normal Htt protein levels nor p53 mRNA or protein levels. Expression microarray analysis was employed to determine the effects of wig-1 suppression on genome-wide expression in mouse liver and brain. Reduction of wig-1 caused both down regulation and up regulation of several genes, and a number of wig-1 regulated genes were identified that potentially links wig-1 various signaling pathways and diseases. Antisense oligonucleotides can effectively reduce wig-1 levels in mouse liver and brain, which results in specific changes in gene expression for pathways relevant to both the nervous system and cancer.

Genomic Analysis of wig-1 Pathways

PubMed Central

Sedaghat, Yalda; Mazur, Curt; Sabripour, Mahyar; Hung, Gene; Monia, Brett P.

2012-01-01

Background Wig-1 is a transcription factor regulated by p53 that can interact with hnRNP A2/B1, RNA Helicase A, and dsRNAs, which plays an important role in RNA and protein stabilization. in vitro studies have shown that wig-1 binds p53 mRNA and stabilizes it by protecting it from deadenylation. Furthermore, p53 has been implicated as a causal factor in neurodegenerative diseases based in part on its selective regulatory function on gene expression, including genes which, in turn, also possess regulatory functions on gene expression. In this study we focused on the wig-1 transcription factor as a downstream p53 regulated gene and characterized the effects of wig-1 down regulation on gene expression in mouse liver and brain. Methods and Results Antisense oligonucleotides (ASOs) were identified that specifically target mouse wig-1 mRNA and produce a dose-dependent reduction in wig-1 mRNA levels in cell culture. These wig-1 ASOs produced marked reductions in wig-1 levels in liver following intraperitoneal administration and in brain tissue following ASO administration through a single striatal bolus injection in FVB and BACHD mice. Wig-1 suppression was well tolerated and resulted in the reduction of mutant Htt protein levels in BACHD mouse brain but had no effect on normal Htt protein levels nor p53 mRNA or protein levels. Expression microarray analysis was employed to determine the effects of wig-1 suppression on genome-wide expression in mouse liver and brain. Reduction of wig-1 caused both down regulation and up regulation of several genes, and a number of wig-1 regulated genes were identified that potentially links wig-1 various signaling pathways and diseases. Conclusion Antisense oligonucleotides can effectively reduce wig-1 levels in mouse liver and brain, which results in specific changes in gene expression for pathways relevant to both the nervous system and cancer. PMID:22347364

A map of terminal regulators of neuronal identity in Caenorhabditis elegans

PubMed Central

2016-01-01

Our present day understanding of nervous system development is an amalgam of insights gained from studying different aspects and stages of nervous system development in a variety of invertebrate and vertebrate model systems, with each model system making its own distinctive set of contributions. One aspect of nervous system development that has been among the most extensively studied in the nematode Caenorhabditis elegans is the nature of the gene regulatory programs that specify hardwired, terminal cellular identities. I first summarize a number of maps (anatomical, functional, and molecular) that describe the terminal identity of individual neurons in the C. elegans nervous system. I then provide a comprehensive summary of regulatory factors that specify terminal identities in the nervous system, synthesizing these past studies into a regulatory map of cellular identities in the C. elegans nervous system. This map shows that for three quarters of all neurons in the C. elegans nervous system, regulatory factors that control terminal identity features are known. In‐depth studies of specific neuron types have revealed that regulatory factors rarely act alone, but rather act cooperatively in neuron‐type specific combinations. In most cases examined so far, distinct, biochemically unlinked terminal identity features are coregulated via cooperatively acting transcription factors, termed terminal selectors, but there are also cases in which distinct identity features are controlled in a piecemeal fashion by independent regulatory inputs. The regulatory map also illustrates that identity‐defining transcription factors are reemployed in distinct combinations in different neuron types. However, the same transcription factor can drive terminal differentiation in neurons that are unrelated by lineage, unrelated by function, connectivity and neurotransmitter deployment. Lastly, the regulatory map illustrates the preponderance of homeodomain transcription factors in the control of terminal identities, suggesting that these factors have ancient, phylogenetically conserved roles in controlling terminal neuronal differentiation in the nervous system. WIREs Dev Biol 2016, 5:474–498. doi: 10.1002/wdev.233 For further resources related to this article, please visit the WIREs website. PMID:27136279

Transmitter responsiveness in two newly isolated clones of neuroblastoma X glioma hybrid.

PubMed

Ogura, A; Amano, T

1983-01-10

Mouse neuroblastoma clone N1E-115 cells and rat glioma clone C6 cells were hybridized and two new clones were isolated. One clone, designated NG115-301, possessed weak electric excitability to an applied current pulse, while another clone, NG115-401, generated an action potential in response to the pulse. The former clone responded to serotonin and catecholamines with slow hyperpolarizations, while the latter clone responded to catecholamines with transient depolarizations. Both clones did not respond to acetylcholine. These types of responses have not been reported in any available clones. These clones may enrich the repertoire of cell clones useful for the characterization of transmitter reception mechanisms in the nervous system.

Adult Mouse Cortical Cell Taxonomy by Single Cell Transcriptomics

PubMed Central

Tasic, Bosiljka; Menon, Vilas; Nguyen, Thuc Nghi; Kim, Tae Kyung; Jarsky, Tim; Yao, Zizhen; Levi, Boaz; Gray, Lucas T.; Sorensen, Staci A.; Dolbeare, Tim; Bertagnolli, Darren; Goldy, Jeff; Shapovalova, Nadiya; Parry, Sheana; Lee, Changkyu; Smith, Kimberly; Bernard, Amy; Madisen, Linda; Sunkin, Susan M.; Hawrylycz, Michael; Koch, Christof; Zeng, Hongkui

2016-01-01

Nervous systems are composed of various cell types, but the extent of cell type diversity is poorly understood. Here, we construct a cellular taxonomy of one cortical region, primary visual cortex, in adult mice based on single cell RNA-sequencing. We identify 49 transcriptomic cell types including 23 GABAergic, 19 glutamatergic and seven non-neuronal types. We also analyze cell-type specific mRNA processing and characterize genetic access to these transcriptomic types by many transgenic Cre lines. Finally, we show that some of our transcriptomic cell types display specific and differential electrophysiological and axon projection properties, thereby confirming that the single cell transcriptomic signatures can be associated with specific cellular properties. PMID:26727548

Heterogeneous incidence and propagation of spreading depolarizations

PubMed Central

Kaufmann, Dan; Theriot, Jeremy J; Zyuzin, Jekaterina; Service, C Austin; Chang, Joshua C; Tang, Y Tanye; Bogdanov, Vladimir B; Multon, Sylvie; Schoenen, Jean; Ju, Y Sungtaek

2016-01-01

Spreading depolarizations are implicated in a diverse set of neurologic diseases. They are unusual forms of nervous system activity in that they propagate very slowly and approximately concentrically, apparently not respecting the anatomic, synaptic, functional, or vascular architecture of the brain. However, there is evidence that spreading depolarizations are not truly concentric, isotropic, or homogeneous, either in space or in time. Here we present evidence from KCl-induced spreading depolarizations, in mouse and rat, in vivo and in vitro, showing the great variability that these depolarizations can exhibit. This variability can help inform the mechanistic understanding of spreading depolarizations, and it has implications for their phenomenology in neurologic disease. PMID:27562866

In vivo simultaneous transcriptional activation of multiple genes in the brain using CRISPR-dCas9-activator transgenic mice.

PubMed

Zhou, Haibo; Liu, Junlai; Zhou, Changyang; Gao, Ni; Rao, Zhiping; Li, He; Hu, Xinde; Li, Changlin; Yao, Xuan; Shen, Xiaowen; Sun, Yidi; Wei, Yu; Liu, Fei; Ying, Wenqin; Zhang, Junming; Tang, Cheng; Zhang, Xu; Xu, Huatai; Shi, Linyu; Cheng, Leping; Huang, Pengyu; Yang, Hui

2018-03-01

Despite rapid progresses in the genome-editing field, in vivo simultaneous overexpression of multiple genes remains challenging. We generated a transgenic mouse using an improved dCas9 system that enables simultaneous and precise in vivo transcriptional activation of multiple genes and long noncoding RNAs in the nervous system. As proof of concept, we were able to use targeted activation of endogenous neurogenic genes in these transgenic mice to directly and efficiently convert astrocytes into functional neurons in vivo. This system provides a flexible and rapid screening platform for studying complex gene networks and gain-of-function phenotypes in the mammalian brain.

MicroRNA-542-5p as a Novel Tumor Suppressor in Neuroblastoma

PubMed Central

Bray, Isabella; Tivnan, Amanda; Bryan, Kenneth; Foley, Niamh H; Watters, Karen M; Tracey, Lorraine; Davidoff, Andrew M; Stallings, Raymond L

2011-01-01

Several studies have implicated the dysregulation of microRNAs in neuroblastoma pathogenesis, an often fatal paediatric cancer arising from precursor cells of the sympathetic nervous system. Our group and others have demonstrated that lower expression of miR-542-5p is highly associated with poor patient survival, indicating a potential tumor suppressive function. Here, we demonstrate that ectopic over-expression of this miRNA decreases the invasive potential of neuroblastoma cell lines in vitro, along with primary tumor growth and metastases in an orthotopic mouse xenograft model, providing the first functional evidence for the involvement of miR-542-5p as a tumor suppressor in any type of cancer. PMID:21310526

The mouse homeobox gene, S8, is expressed during embryogenesis predominantly in mesenchyme.

PubMed

Opstelten, D J; Vogels, R; Robert, B; Kalkhoven, E; Zwartkruis, F; de Laaf, L; Destrée, O H; Deschamps, J; Lawson, K A; Meijlink, F

1991-03-01

The murine S8 gene, originally identified by Kongsuwan et al. [EMBO J. 7(1988)2131-2138] encodes a homeodomain which resembles those of the paired family. We studied the expression pattern during mid-gestation embryogenesis of S8 by in situ hybridization. Expression was detected locally in craniofacial mesenchyme, in the limb, the heart and the somites and sclerotomes all along the axis, and was absent from the central and peripheral nervous system, splanchnopleure, and endodermal derivatives. This pattern differs considerably from that of most previously described homeobox containing genes. By genetic analysis, the gene was located on chromosome 2, about 20 cM from the HOX-4 cluster.

Production and characterization of immortal human neural stem cell line with multipotent differentiation property.

PubMed

Kim, Seung U; Nagai, Atsushi; Nakagawa, Eiji; Choi, Hyun B; Bang, Jung H; Lee, Hong J; Lee, Myung A; Lee, Yong B; Park, In H

2008-01-01

We document the protocols and methods for the production of immortalized cell lines of human neural stem cells from the human fetal central nervous system (CNS) cells by using a retroviral vector encoding v-myc oncogene. One of the human neural stem cell lines (HB1.F3) was found to express nestin and other specific markers for human neural stem cells, giving rise to three fundamental cell types of the CNS: neurons, astrocytes, and oligodendrocytes. After transplantation into the brain of mouse model of stroke, implanted human neural stem cells were observed to migrate extensively from the site of implantation into other anatomical sites and to differentiate into neurons and glial cells.

Property of lysosomal storage disease associated with midbrain pathology in the central nervous system of Lamp-2-deficient mice.

PubMed

Furuta, Akiko; Kikuchi, Hisae; Fujita, Hiromi; Yamada, Daisuke; Fujiwara, Yuuki; Kabuta, Tomohiro; Nishino, Ichizo; Wada, Keiji; Uchiyama, Yasuo

2015-06-01

Lysosome-associated membrane protein-2 (LAMP-2) is the gene responsible for Danon disease, which is characterized by cardiomyopathy, autophagic vacuolar myopathy, and variable mental retardation. To elucidate the function of LAMP-2 in the central nervous system, we investigated the neuropathological changes in Lamp-2-deficient mice. Immunohistochemical observations revealed that Lamp-1 and cathepsin D-positive lysosomal structures increased in the large neurons of the mouse brain. Ubiquitin-immunoreactive aggregates and concanavalin A-positive materials were detected in these neurons. By means of ultrastructural studies, we found various-shaped accumulations, including lipofuscin, glycolipid-like materials, and membranous structures, in the neurons and glial cells of Lamp-2-deficient brains. In deficient mice, glycogen granules accumulated in hepatocyte lysosomes but were not observed in neurons. These pathological features indicate lysosomal storage disease; however, the findings are unlikely a consequence of deficiency of a single lysosomal enzyme. Although previous study results have shown a large amount of autophagic vacuoles in parenchymal cells of the visceral organs, these findings were rarely detected in the brain tissue except for some axons in the substantia nigra, in which abundant activated microglial cells with increased lipid peroxidation were observed. Thus, LAMP-2 in the central nervous system has a possible role in the degradation of the various macromolecules in lysosomes and an additional function concerning protection from oxidative stress, especially in the substantia nigra. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

miRNAs in brain development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petri, Rebecca; Malmevik, Josephine; Fasching, Liana

2014-02-01

MicroRNAs (miRNAs) are small, non-coding RNAs that negatively regulate gene expression at the post-transcriptional level. In the brain, a large number of miRNAs are expressed and there is a growing body of evidence demonstrating that miRNAs are essential for brain development and neuronal function. Conditional knockout studies of the core components in the miRNA biogenesis pathway, such as Dicer and DGCR8, have demonstrated a crucial role for miRNAs during the development of the central nervous system. Furthermore, mice deleted for specific miRNAs and miRNA-clusters demonstrate diverse functional roles for different miRNAs during the development of different brain structures. miRNAs havemore » been proposed to regulate cellular functions such as differentiation, proliferation and fate-determination of neural progenitors. In this review we summarise the findings from recent studies that highlight the importance of miRNAs in brain development with a focus on the mouse model. We also discuss the technical limitations of current miRNA studies that still limit our understanding of this family of non-coding RNAs and propose the use of novel and refined technologies that are needed in order to fully determine the impact of specific miRNAs in brain development. - Highlights: • miRNAs are essential for brain development and neuronal function. • KO of Dicer is embryonically lethal. • Conditional Dicer KO results in defective proliferation or increased apoptosis. • KO of individual miRNAs or miRNA families is necessary to determine function.« less