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Giron C, Hélie P, Parent J, Boutin M, St-Jean G. Clinical, imaging and histopathological characterization of a series of three cats with cerebellar cortical degeneration. BMC Vet Res 2024; 20:263. [PMID: 38890680 PMCID: PMC11186075 DOI: 10.1186/s12917-024-04127-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 06/10/2024] [Indexed: 06/20/2024] Open
Abstract
BACKGROUND Neurological inherited disorders are rare in domestic animals. Cerebellar cortical degeneration remains amongst the most common of these disorders. The condition is defined as the premature loss of fully differentiated cerebellar components due to genetic or metabolic defects. It has been studied in dogs and cats, and various genetic defects and diagnostic tests (including magnetic resonance imaging (MRI)) have been refined in these species. Cases in cats remain rare and mostly individual, and few diagnostic criteria, other than post-mortem exam, have been evaluated in reports with multiple cases. Here, we report three feline cases of cerebellar cortical degeneration with detailed clinical, diagnostic imaging and post-mortem findings. CASE PRESENTATION The three cases were directly (siblings, case #1 and #2) or indirectly related (same farm, case #3) and showed early-onset of the disease, with clinical signs including cerebellar ataxia and tremors. Brain MRI was highly suggestive of cerebellar cortical degeneration on all three cases. The relative cerebrospinal fluid (CSF) space, relative cerebellum size, brainstem: cerebellum area ratio, and cerebellum: total brain area ratio, were measured and compared to a control group of cats and reference cut-offs for dogs in the literature. For the relative cerebellum size and cerebellum: total brain area ratio, all affected cases had a lower value than the control group. For the relative CSF space and brainstem: cerebellum area ratio, the more affected cases (#2 and #3) had higher values than the control group, while the least affected case (#3) had values within the ranges of the control group, but a progression was visible over time. Post-mortem examination confirmed the diagnosis of cerebellar cortical degeneration, with marked to complete loss of Purkinje cells and associated granular layer depletion and proliferation of Bergmann glia. One case also had Wallerian-like degeneration in the spinal cord, suggestive of spinocerebellar degeneration. CONCLUSION Our report further supports a potential genetic component for the disease in cats. For the MRI examination, the relative cerebellum size and cerebellum: total brain area ratio seem promising, but further studies are needed to establish specific feline cut-offs. Post-mortem evaluation of the cerebellum remains the gold standard for the final diagnosis.
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Affiliation(s)
- Céline Giron
- Department of clinical sciences, Faculty of veterinary medicine, Université de Montréal, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Pierre Hélie
- Department of pathology and microbiology, Faculty of veterinary medicine, Université de Montréal, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Joane Parent
- Department of clinical sciences, Faculty of veterinary medicine, Université de Montréal, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Mathieu Boutin
- Department of clinical sciences, Faculty of veterinary medicine, Université de Montréal, Saint-Hyacinthe, QC, J2S 2M2, Canada
| | - Guillaume St-Jean
- Department of pathology and microbiology, Faculty of veterinary medicine, Université de Montréal, Saint-Hyacinthe, QC, J2S 2M2, Canada.
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2
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Tejwani L, Ravindra NG, Lee C, Cheng Y, Nguyen B, Luttik K, Ni L, Zhang S, Morrison LM, Gionco J, Xiang Y, Yoon J, Ro H, Haidery F, Grijalva RM, Bae E, Kim K, Martuscello RT, Orr HT, Zoghbi HY, McLoughlin HS, Ranum LPW, Shakkottai VG, Faust PL, Wang S, van Dijk D, Lim J. Longitudinal single-cell transcriptional dynamics throughout neurodegeneration in SCA1. Neuron 2024; 112:362-383.e15. [PMID: 38016472 PMCID: PMC10922326 DOI: 10.1016/j.neuron.2023.10.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 09/10/2023] [Accepted: 10/27/2023] [Indexed: 11/30/2023]
Abstract
Neurodegeneration is a protracted process involving progressive changes in myriad cell types that ultimately results in the death of vulnerable neuronal populations. To dissect how individual cell types within a heterogeneous tissue contribute to the pathogenesis and progression of a neurodegenerative disorder, we performed longitudinal single-nucleus RNA sequencing of mouse and human spinocerebellar ataxia type 1 (SCA1) cerebellar tissue, establishing continuous dynamic trajectories of each cell population. Importantly, we defined the precise transcriptional changes that precede loss of Purkinje cells and, for the first time, identified robust early transcriptional dysregulation in unipolar brush cells and oligodendroglia. Finally, we applied a deep learning method to predict disease state accurately and identified specific features that enable accurate distinction of wild-type and SCA1 cells. Together, this work reveals new roles for diverse cerebellar cell types in SCA1 and provides a generalizable analysis framework for studying neurodegeneration.
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Affiliation(s)
- Leon Tejwani
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA.
| | - Neal G Ravindra
- Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Computer Science, Yale University, New Haven, CT 06510, USA
| | - Changwoo Lee
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yubao Cheng
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Billy Nguyen
- University of California, San Francisco School of Medicine, San Francisco, CA 94143, USA
| | - Kimberly Luttik
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Luhan Ni
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Shupei Zhang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Logan M Morrison
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - John Gionco
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Yangfei Xiang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Hannah Ro
- Yale College, New Haven, CT 06510, USA
| | | | - Rosalie M Grijalva
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Kristen Kim
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA
| | - Regina T Martuscello
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Harry T Orr
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Huda Y Zoghbi
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hayley S McLoughlin
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Laura P W Ranum
- Department of Molecular Genetics and Microbiology, Center for Neurogenetics, College of Medicine, Genetics Institute, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Vikram G Shakkottai
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Siyuan Wang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Department of Cell Biology, Yale School of Medicine, New Haven, CT 06510, USA.
| | - David van Dijk
- Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Computer Science, Yale University, New Haven, CT 06510, USA.
| | - Janghoo Lim
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06510, USA; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale School of Medicine, New Haven, CT 06510, USA; Wu Tsai Institute, Yale School of Medicine, New Haven, CT 06510, USA.
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3
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Sheng L, Luo Q, Chen L. Amino Acid Solute Carrier Transporters in Inflammation and Autoimmunity. Drug Metab Dispos 2022; 50:DMD-AR-2021-000705. [PMID: 35152203 DOI: 10.1124/dmd.121.000705] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 01/14/2022] [Accepted: 01/27/2022] [Indexed: 02/21/2024] Open
Abstract
The past decade exposed the importance of many homeostasis and metabolism related proteins in autoimmunity disease and inflammation. Solute carriers (SLCs) are a group of membrane channels that can transport amino acids, the building blocks of proteins, nutrients, and neurotransmitters. This review summarizes the role of SLCs amino acid transporters in inflammation and autoimmunity disease. In detail, the importance of Glutamate transporters SLC1A1, SLC1A2, and SLC1A3, mainly expressed in the brain where they help prevent glutamate excitotoxicity, is discussed in the context of central nervous system disorders such as multiple sclerosis. Similarly, the cationic amino acid transporter SLC7A1 (CAT1), which is an important arginine transporter for T cells, and SLC7A2 (CAT2), essential for innate immunity. SLC3 family proteins, which bind with light chains from the SLC7 family (SLC7A5, SLC7A7 and SLC7A11) to form heteromeric amino acid transporters, are also explored to describe their roles in T cells, NK cells, macrophages and tumor immunotherapies. Altogether, the link between SLC amino acid transporters with inflammation and autoimmunity may contribute to a better understanding of underlying mechanism of disease and provide novel potential therapeutic avenues. Significance Statement SIGNIFICANCE STATEMENT In this review, we summarize the link between SLC amino acid transporters and inflammation and immune responses, specially SLC1 family members and SLC7 members. Studying the link may contribute to a better understanding of related diseases and provide potential therapeutic targets and useful to the researchers who have interest in the involvement of amino acids in immunity.
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Affiliation(s)
| | - Qi Luo
- Tsinghua University, China
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4
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Sphingolipid metabolism governs Purkinje cell patterned degeneration in Atxn1[82Q]/+ mice. Proc Natl Acad Sci U S A 2021; 118:2016969118. [PMID: 34479994 PMCID: PMC8433568 DOI: 10.1073/pnas.2016969118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 07/19/2021] [Indexed: 01/02/2023] Open
Abstract
Neuronal subtypes are differentially affected by neuropathologies. For example, Purkinje cells, the principal neurons of the cerebellum, can be divided in subpopulations based on their sensitivity to pathological insult. However, the molecular mechanisms explaining why, among seemingly identical neurons, some will degenerate while others survive remain unknown. Here, we analyzed, in a disease model of cerebellar neurodegeneration, the metabolism of sphingolipids, complex lipids involved in cell apoptosis, and found that specific sphingolipids accumulate in the cerebellar region primarily affected by neurodegeneration. Preventing this accumulation by disrupting sphingolipid metabolism via genetic mutation caused a neuroprotective effect on subpopulations of Purkinje cells. Thus, our data indicate that sphingolipid metabolism is involved in the predisposition of neuronal subtypes to neurodegeneration. Patterned degeneration of Purkinje cells (PCs) can be observed in a wide range of neuropathologies, but mechanisms behind nonrandom cerebellar neurodegeneration remain unclear. Sphingolipid metabolism dyshomeostasis typically leads to PC neurodegeneration; hence, we questioned whether local sphingolipid balance underlies regional sensitivity to pathological insults. Here, we investigated the regional compartmentalization of sphingolipids and their related enzymes in the cerebellar cortex in healthy and pathological conditions. Analysis in wild-type animals revealed higher sphingosine kinase 1 (Sphk1) levels in the flocculonodular cerebellum, while sphingosine-1-phosphate (S1P) levels were higher in the anterior cerebellum. Next, we investigated a model for spinocerebellar ataxia type 1 (SCA1) driven by the transgenic expression of the expanded Ataxin 1 protein with 82 glutamine (82Q), exhibiting severe PC degeneration in the anterior cerebellum while the flocculonodular region is preserved. In Atxn1[82Q]/+ mice, we found that levels of Sphk1 and Sphk2 were region-specific decreased and S1P levels increased, particularly in the anterior cerebellum. To determine if there is a causal link between sphingolipid levels and neurodegeneration, we deleted the Sphk1 gene in Atxn1[82Q]/+ mice. Analysis of Atxn1[82Q]/+; Sphk1−/− mice confirmed a neuroprotective effect, rescuing a subset of PCs in the anterior cerebellum, in domains reminiscent of the modules defined by AldolaseC expression. Finally, we showed that Sphk1 deletion acts on the ATXN1[82Q] protein expression and prevents PC degeneration. Taken together, our results demonstrate that there are regional differences in sphingolipid metabolism and that this metabolism is directly involved in PC degeneration in Atxn1[82Q]/+ mice.
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The Amino Acid-mTORC1 Pathway Mediates APEC TW-XM-Induced Inflammation in bEnd.3 Cells. Int J Mol Sci 2021; 22:ijms22179245. [PMID: 34502151 PMCID: PMC8431488 DOI: 10.3390/ijms22179245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/19/2021] [Accepted: 08/24/2021] [Indexed: 11/16/2022] Open
Abstract
The blood-brain barrier (BBB) is key to establishing and maintaining homeostasis in the central nervous system (CNS); meningitis bacterial infection can disrupt the integrity of BBB by inducing an inflammatory response. The changes in the cerebral uptake of amino acids may contribute to inflammatory response during infection and were accompanied by high expression of amino acid transporters leading to increased amino acid uptake. However, it is unclear whether amino acid uptake is changed and how to affect inflammatory responses in mouse brain microvascular endothelial (bEnd.3) cells in response to Avian Pathogenic Escherichia coli TW-XM (APEC XM) infection. Here, we firstly found that APEC XM infection could induce serine (Ser) and glutamate (Glu) transport from extracellular into intracellular in bEnd.3 cells. Meanwhile, we also shown that the expression sodium-dependent neutral amino acid transporter 2 (SNAT2) for Ser and excitatory amino acid transporter 4 (EAAT4) for Glu was also significantly elevated during infection. Then, in amino acid deficiency or supplementation medium, we found that Ser or Glu transport were involving in increasing SNAT2 or EAAT4 expression, mTORC1 (mechanistic target of rapamycin complex 1) activation and inflammation, respectively. Of note, Ser or Glu transport were inhibited after SNAT2 silencing or EAAT4 silencing, resulting in inhibition of mTORC1 pathway activation, and inflammation compared with the APEC XM infection group. Moreover, pEGFP-SNAT2 overexpression and pEGFP-EAAT4 overexpression in bEnd.3 cells all could promote amino acid uptake, activation of the mTORC1 pathway and inflammation during infection. We further found mTORC1 silencing could inhibit inflammation, the expression of SNAT2 and EAAT4, and amino acid uptake. Taken together, our results demonstrated that APEC TW-XM infection can induce Ser or Glu uptake depending on amino acid transporters transportation, and then activate amino acid-mTORC1 pathway to induce inflammation in bEnd.3 cells.
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6
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Naughton M, McMahon J, Healy S, FitzGerald U. Profile of the unfolded protein response in rat cerebellar cortical development. J Comp Neurol 2019; 527:2910-2924. [PMID: 31132146 DOI: 10.1002/cne.24718] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 04/01/2019] [Accepted: 05/16/2019] [Indexed: 12/13/2022]
Abstract
The unfolded protein response (UPR) has been reported during normal development of cortical neurons and cerebellar white matter and may also contribute to the pathogenesis of neurological conditions, such as Marinesco-Sjogren syndrome and Borna virus infection, which result in cerebellar defects. The UPR is initiated when the processing capacity of the endoplasmic reticulum (ER) is overwhelmed. Misfolded proteins accumulate and can activate ER stress sensors; PKR-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1 (IRE1), activated transcription factor 6 (ATF6) and their downstream targets glucose-regulated protein 78 (GRP78), glucose-regulated protein 94 (GRP94) and protein disulfide isomerase (PDI). In order to provide a fuller appreciation of the possible importance of ER stress-associated proteins in the context of cerebellar disease, we have profiled the expression of ER stress sensors and their downstream targets in the developing cerebellar cortex in postnatal rat. Activation of PERK and IRE1 stress sensors was observed for the first time in normally developing granule cell precursors. A second proliferative pPERK-positive population was also detected in the internal granular layer (IGL). In general, the density of UPR protein-positive cells was found to decrease significantly when profiles in early and late postnatal ages were compared. These data may be relevant to studies of medulloblastoma and warrant further investigation.
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Affiliation(s)
- Michelle Naughton
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Jill McMahon
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Sinéad Healy
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Una FitzGerald
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
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7
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Prusty BK, Gulve N, Govind S, Krueger GRF, Feichtinger J, Larcombe L, Aspinall R, Ablashi DV, Toro CT. Active HHV-6 Infection of Cerebellar Purkinje Cells in Mood Disorders. Front Microbiol 2018; 9:1955. [PMID: 30186267 PMCID: PMC6110891 DOI: 10.3389/fmicb.2018.01955] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/02/2018] [Indexed: 12/25/2022] Open
Abstract
Early-life infections and associated neuroinflammation is incriminated in the pathogenesis of various mood disorders. Infection with human roseoloviruses, HHV-6A and HHV-6B, allows viral latency in the central nervous system and other tissues, which can later be activated causing cognitive and behavioral disturbances. Hence, this study was designed to evaluate possible association of HHV-6A and HHV-6B activation with three different groups of psychiatric patients. DNA qPCR, immunofluorescence and FISH studies were carried out in post-mortem posterior cerebellum from 50 cases each of bipolar disorder (BPD), schizophrenia, 15 major depressive disorder (MDD) and 50 appropriate control samples obtained from two well-known brain collections (Stanley Medical Research Institute). HHV-6A and HHV-6B late proteins (indicating active infection) and viral DNA were detected more frequently (p < 0.001 for each virus) in human cerebellum in MDD and BPD relative to controls. These roseolovirus proteins and DNA were found less frequently in schizophrenia cases. Active HHV-6A and HHV-6B infection in cerebellar Purkinje cells were detected frequently in BPD and MDD cases. Furthermore, we found a significant association of HHV-6A infection with reduced Purkinje cell size, suggesting virus-mediated abnormal Purkinje cell function in these disorders. Finally, gene expression analysis of cerebellar tissue revealed changes in pathways reflecting an inflammatory response possibly to HHV-6A infection. Our results provide molecular evidence to support a role for active HHV-6A and HHV-6B infection in BPD and MDD.
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Affiliation(s)
- Bhupesh K Prusty
- Biocenter, Department of Microbiology, University of Würzburg, Würzburg, Germany.,Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Nitish Gulve
- Biocenter, Department of Microbiology, University of Würzburg, Würzburg, Germany
| | - Sheila Govind
- Division of Virology, National Institute for Biological Standards and Control, Hertfordshire, United Kingdom
| | - Gerhard R F Krueger
- Department of Pathology and Laboratory Medicine, UT-Houston Medical School, Houston, TX, United States
| | - Julia Feichtinger
- Institute of Computational Biotechnology, Graz University of Technology, Graz, Austria.,BioTechMed Omics Center, Graz, Austria
| | - Lee Larcombe
- Applied Exomics Ltd., Stevenage Bioscience Catalyst, Stevenage, United Kingdom
| | - Richard Aspinall
- Faculty of Health and Life Sciences, Coventry University, Coventry, United Kingdom
| | | | - Carla T Toro
- HHV-6 Foundation, Santa Barbara, CA, United States.,The Institute of Digital Healthcare, The University of Warwick, Warwick, United Kingdom
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Reeber SL, Arancillo M, Sillitoe RV. Bergmann Glia are Patterned into Topographic Molecular Zones in the Developing and Adult Mouse Cerebellum. CEREBELLUM (LONDON, ENGLAND) 2018; 17:392-403. [PMID: 24906823 PMCID: PMC4291305 DOI: 10.1007/s12311-014-0571-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Cerebellar circuits are patterned into an array of topographic parasagittal domains called zones. Zones are best revealed by gene expression, circuit anatomy, and cellular degeneration patterns. Thus far, the study of zones has been focused heavily on how neurons are organized. Because of this, detailed neuronal patterning maps have been established for Purkinje cells, granule cells, Golgi cells, unipolar brush cells, and also for the terminal field organization of climbing fiber and mossy fiber afferents. In comparison, however, it remains poorly understood if glial cells are also organized into zones. We have identified an Npy-Gfp BAC transgenic mouse line (Tau-Sapphire Green fluorescent protein (Gfp) is under the control of the neuropeptide Y (Npy) gene regulatory elements) that can be used to label Bergmann glial cells with Golgi-like resolution. In these adult transgenic mice, we found that Npy-Gfp expression was localized to Bergmann glia mainly in lobules VI/VII and IX/X. Using double immunofluorescence, we show that in these lobules, Npy-Gfp expression in the Bergmann glia overlaps with the pattern of the small heat shock protein HSP25, a Purkinje cell marker for zones located in lobules VI/VII and IX/X. Developmental analysis starting from the day of birth showed that HSP25 and Npy-Gfp expression follow a similar program of spatial and temporal patterning. However, loss of Npy signaling did not alter the patterning of Purkinje cell zones. We conclude that Bergmann glial cells are zonally organized and their patterns are restricted by boundaries that also confine cerebellar neurons into a topographic circuit map.
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Affiliation(s)
- Stacey L Reeber
- Department of Pathology and Immunology, Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Marife Arancillo
- Department of Pathology and Immunology, Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Roy V Sillitoe
- Department of Pathology and Immunology, Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.
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9
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Beckinghausen J, Sillitoe RV. Insights into cerebellar development and connectivity. Neurosci Lett 2018; 688:2-13. [PMID: 29746896 DOI: 10.1016/j.neulet.2018.05.013] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 05/04/2018] [Accepted: 05/06/2018] [Indexed: 02/06/2023]
Abstract
The cerebellum has a well-established role in controlling motor functions such coordination, balance, posture, and skilled learning. There is mounting evidence that it might also play a critical role in non-motor functions such as cognition and emotion. It is therefore not surprising that cerebellar defects are associated with a wide array of diseases including ataxia, dystonia, tremor, schizophrenia, dyslexia, and autism spectrum disorder. What is intriguing is that a seemingly uniform circuit that is often described as being "simple" should carry out all of these behaviors. Analyses of how cerebellar circuits develop have revealed that such descriptions massively underestimate the complexity of the cerebellum. The cerebellum is in fact highly patterned and organized around a series of parasagittal stripes and transverse zones. This topographic architecture partitions all cerebellar circuits into functional modules that are thought to enhance processing power during cerebellar dependent behaviors. What are arguably the most remarkable features of cerebellar topography are the developmental processes that produce them. This review is concerned with the genetic and cellular mechanisms that orchestrate cerebellar patterning. We place a major focus on how Purkinje cells control multiple aspects of cerebellar circuit assembly. Using this model, we discuss evidence for how "zebra-like" patterns in Purkinje cells sculpt the cerebellum, how specific genetic cues mediate the process, and how activity refines the patterns into an adult map that is capable of executing various functions. We also discuss how defective Purkinje cell patterning might impact the pathogenesis of neurological conditions.
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Affiliation(s)
- Jaclyn Beckinghausen
- Department of Pathology and Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Department of Neuroscience, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of TX Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Roy V Sillitoe
- Department of Pathology and Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Department of Neuroscience, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA; Jan and Dan Duncan Neurological Research Institute of TX Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.
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10
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Central Nervous System Infection with Borna Disease Virus Causes Kynurenine Pathway Dysregulation and Neurotoxic Quinolinic Acid Production. J Virol 2017; 91:JVI.00673-17. [PMID: 28446679 PMCID: PMC5487560 DOI: 10.1128/jvi.00673-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 04/19/2017] [Indexed: 12/27/2022] Open
Abstract
Central nervous system infection of neonatal and adult rats with Borna disease virus (BDV) results in neuronal destruction and behavioral abnormalities with differential immune-mediated involvement. Neuroactive metabolites generated from the kynurenine pathway of tryptophan degradation have been implicated in several human neurodegenerative disorders. Here, we report that brain expression of key enzymes in the kynurenine pathway are significantly, but differentially, altered in neonatal and adult rats with BDV infection. Gene expression analysis of rat brains following neonatal infection showed increased expression of kynurenine amino transferase II (KATII) and kynurenine-3-monooxygenase (KMO) enzymes. Additionally, indoleamine 2,3-dioxygenase (IDO) expression was only modestly increased in a brain region- and time-dependent manner in neonatally infected rats; however, its expression was highly increased in adult infected rats. The most dramatic impact on gene expression was seen for KMO, whose activity promotes the production of neurotoxic quinolinic acid. KMO expression was persistently elevated in brain regions of both newborn and adult BDV-infected rats, with increases reaching up to 86-fold. KMO protein levels were increased in neonatally infected rats and colocalized with neurons, the primary target cells of BDV infection. Furthermore, quinolinic acid was elevated in neonatally infected rat brains. We further demonstrate increased expression of KATII and KMO, but not IDO, in vitro in BDV-infected C6 astroglioma cells. Our results suggest that BDV directly impacts the kynurenine pathway, an effect that may be exacerbated by inflammatory responses in immunocompetent hosts. Thus, experimental models of BDV infection may provide new tools for discriminating virus-mediated from immune-mediated impacts on the kynurenine pathway and their relative contribution to neurodegeneration.IMPORTANCE BDV causes persistent, noncytopathic infection in vitro yet still elicits widespread neurodegeneration of infected neurons in both immunoincompetent and immunocompetent hosts. Here, we show that BDV infection induces expression of key enzymes of the kynurenine pathway in brains of newborn and adult infected rats and cultured astroglioma cells, shunting tryptophan degradation toward the production of neurotoxic quinolinic acid. Thus, our findings newly implicate this metabolic pathway in BDV-induced neurodegeneration. Given the importance of the kynurenine pathway in a wide range of human infections and neurodegenerative and neuropsychiatric disorders, animal models of BDV infection may serve as important tools for contrasting direct viral and indirect antiviral immune-mediated impacts on kynurenine pathway dysregulation and the ensuing neurodevelopmental and neuropathological consequences.
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White JJ, Arancillo M, King A, Lin T, Miterko LN, Gebre SA, Sillitoe RV. Pathogenesis of severe ataxia and tremor without the typical signs of neurodegeneration. Neurobiol Dis 2015; 86:86-98. [PMID: 26586559 DOI: 10.1016/j.nbd.2015.11.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 10/30/2015] [Accepted: 11/11/2015] [Indexed: 11/27/2022] Open
Abstract
Neurological diseases are especially devastating when they involve neurodegeneration. Neuronal destruction is widespread in cognitive disorders such as Alzheimer's and regionally localized in motor disorders such as Parkinson's, Huntington's, and ataxia. But, surprisingly, the onset and progression of these diseases can occur without neurodegeneration. To understand the origins of diseases that do not have an obvious neuropathology, we tested how loss of CAR8, a regulator of IP3R1-mediated Ca(2+)-signaling, influences cerebellar circuit formation and neural function as movement deteriorates. We found that faulty molecular patterning, which shapes functional circuits called zones, leads to alterations in cerebellar wiring and Purkinje cell activity, but not to degeneration. Rescuing Purkinje cell function improved movement and reducing their Ca(2+) influx eliminated ectopic zones. Our findings in Car8(wdl) mutant mice unveil a pathophysiological mechanism that may operate broadly to impact motor and non-motor conditions that do not involve degeneration.
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Affiliation(s)
- Joshua J White
- Department of Pathology & Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Department of Neuroscience, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA
| | - Marife Arancillo
- Department of Pathology & Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA
| | - Annesha King
- Department of Pathology & Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA
| | - Tao Lin
- Department of Pathology & Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA
| | - Lauren N Miterko
- Program in Developmental Biology, Baylor College of Medicine, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA
| | - Samrawit A Gebre
- Department of Pathology & Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA
| | - Roy V Sillitoe
- Department of Pathology & Immunology, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Department of Neuroscience, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX 77030, USA
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Redefining the cerebellar cortex as an assembly of non-uniform Purkinje cell microcircuits. Nat Rev Neurosci 2015; 16:79-93. [PMID: 25601779 DOI: 10.1038/nrn3886] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The adult mammalian cerebellar cortex is generally assumed to have a uniform cytoarchitecture. Differences in cerebellar function are thought to arise primarily through distinct patterns of input and output connectivity rather than as a result of variations in cortical microcircuitry. However, evidence from anatomical, physiological and genetic studies is increasingly challenging this orthodoxy, and there are now various lines of evidence indicating that the cerebellar cortex is not uniform. Here, we develop the hypothesis that regional differences in properties of cerebellar cortical microcircuits lead to important differences in information processing.
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Zhang L, Liu S, Zhang L, You H, Huang R, Sun L, He P, Chen S, Zhang H, Xie P. Real-time qPCR identifies suitable reference genes for Borna disease virus-infected rat cortical neurons. Int J Mol Sci 2014; 15:21825-39. [PMID: 25431926 PMCID: PMC4284680 DOI: 10.3390/ijms151221825] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 09/21/2014] [Accepted: 09/25/2014] [Indexed: 01/02/2023] Open
Abstract
Quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) is the most commonly-used technique to identify gene expression profiles. The selection of stably expressed reference genes is a prerequisite to properly evaluating gene expression. Here, the suitability of commonly-used reference genes in normalizing RT-qPCR assays of mRNA expression in cultured rat cortical neurons infected with Borna disease virus (BDV) was assessed. The expressions of eight commonly-used reference genes were comparatively analyzed in BDV-infected rat cortical neurons and non-infected control neurons mainly across 9 and 12 days post-infection. These reference genes were validated by RT-qPCR and separately ranked by four statistical algorithms: geNorm, NormFinder, BestKeeper and the comparative delta-Ct method. Then, the RankAggreg package was used to construct consensus rankings. ARBP was found to be the most stable internal control gene at Day 9, and ACTB at Day 12. As the assessment of the validity of the selected reference genes confirms the suitability of applying a combination of the two most stable references genes, combining the two most stable genes for normalization of RT-qPCR studies in BDV-infected rat cortical neurons is recommended at each time point. This study can contribute to improving BDV research by providing the means by which to obtain more reliable and accurate gene expression measurements.
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Affiliation(s)
- Lujun Zhang
- Department of Neurology, Yongchuan Hospital, Chongqing Medical University, Chongqing 402460, China.
| | - Siwen Liu
- Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China.
| | - Liang Zhang
- Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China.
| | - Hongmin You
- Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China.
| | - Rongzhong Huang
- Department of Rehabilitation, the Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China.
| | - Lin Sun
- Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China.
| | - Peng He
- Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China.
| | - Shigang Chen
- Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China.
| | - Hong Zhang
- Chongqing Key Laboratory of Neurobiology, Chongqing 400016, China.
| | - Peng Xie
- Department of Neurology, Yongchuan Hospital, Chongqing Medical University, Chongqing 402460, China.
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Paine MG, Che D, Li L, Neumar RW. Cerebellar Purkinje cell neurodegeneration after cardiac arrest: Effect of therapeutic hypothermia. Resuscitation 2012; 83:1511-6. [DOI: 10.1016/j.resuscitation.2012.05.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 05/06/2012] [Accepted: 05/21/2012] [Indexed: 12/31/2022]
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Fatemi SH, Aldinger KA, Ashwood P, Bauman ML, Blaha CD, Blatt GJ, Chauhan A, Chauhan V, Dager SR, Dickson PE, Estes AM, Goldowitz D, Heck DH, Kemper TL, King BH, Martin LA, Millen KJ, Mittleman G, Mosconi MW, Persico AM, Sweeney JA, Webb SJ, Welsh JP. Consensus paper: pathological role of the cerebellum in autism. CEREBELLUM (LONDON, ENGLAND) 2012; 11:777-807. [PMID: 22370873 PMCID: PMC3677555 DOI: 10.1007/s12311-012-0355-9] [Citation(s) in RCA: 456] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
There has been significant advancement in various aspects of scientific knowledge concerning the role of cerebellum in the etiopathogenesis of autism. In the current consensus paper, we will observe the diversity of opinions regarding the involvement of this important site in the pathology of autism. Recent emergent findings in literature related to cerebellar involvement in autism are discussed, including: cerebellar pathology, cerebellar imaging and symptom expression in autism, cerebellar genetics, cerebellar immune function, oxidative stress and mitochondrial dysfunction, GABAergic and glutamatergic systems, cholinergic, dopaminergic, serotonergic, and oxytocin-related changes in autism, motor control and cognitive deficits, cerebellar coordination of movements and cognition, gene-environment interactions, therapeutics in autism, and relevant animal models of autism. Points of consensus include presence of abnormal cerebellar anatomy, abnormal neurotransmitter systems, oxidative stress, cerebellar motor and cognitive deficits, and neuroinflammation in subjects with autism. Undefined areas or areas requiring further investigation include lack of treatment options for core symptoms of autism, vermal hypoplasia, and other vermal abnormalities as a consistent feature of autism, mechanisms underlying cerebellar contributions to cognition, and unknown mechanisms underlying neuroinflammation.
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Affiliation(s)
- S Hossein Fatemi
- University of Minnesota Medical School, 420 Delaware St. SE, Minneapolis, MN 55455, USA.
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Williams BL, Hornig M, Buie T, Bauman ML, Cho Paik M, Wick I, Bennett A, Jabado O, Hirschberg DL, Lipkin WI. Impaired carbohydrate digestion and transport and mucosal dysbiosis in the intestines of children with autism and gastrointestinal disturbances. PLoS One 2011; 6:e24585. [PMID: 21949732 PMCID: PMC3174969 DOI: 10.1371/journal.pone.0024585] [Citation(s) in RCA: 318] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 08/14/2011] [Indexed: 12/11/2022] Open
Abstract
Gastrointestinal disturbances are commonly reported in children with autism, complicate clinical management, and may contribute to behavioral impairment. Reports of deficiencies in disaccharidase enzymatic activity and of beneficial responses to probiotic and dietary therapies led us to survey gene expression and the mucoepithelial microbiota in intestinal biopsies from children with autism and gastrointestinal disease and children with gastrointestinal disease alone. Ileal transcripts encoding disaccharidases and hexose transporters were deficient in children with autism, indicating impairment of the primary pathway for carbohydrate digestion and transport in enterocytes. Deficient expression of these enzymes and transporters was associated with expression of the intestinal transcription factor, CDX2. Metagenomic analysis of intestinal bacteria revealed compositional dysbiosis manifest as decreases in Bacteroidetes, increases in the ratio of Firmicutes to Bacteroidetes, and increases in Betaproteobacteria. Expression levels of disaccharidases and transporters were associated with the abundance of affected bacterial phylotypes. These results indicate a relationship between human intestinal gene expression and bacterial community structure and may provide insights into the pathophysiology of gastrointestinal disturbances in children with autism.
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Affiliation(s)
- Brent L Williams
- Center for Infection and Immunity, Columbia University, New York, New York, United States of America
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Intracerebral Borna disease virus infection of bank voles leading to peripheral spread and reverse transcription of viral RNA. PLoS One 2011; 6:e23622. [PMID: 21935357 PMCID: PMC3174072 DOI: 10.1371/journal.pone.0023622] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 07/21/2011] [Indexed: 12/17/2022] Open
Abstract
Bornaviruses, which chronically infect many species, can cause severe neurological diseases in some animal species; their association with human neuropsychiatric disorders is, however, debatable. The epidemiology of Borna disease virus (BDV), as for other members of the family Bornaviridae, is largely unknown, although evidence exists for a reservoir in small mammals, for example bank voles (Myodes glareolus). In addition to the current exogenous infections and despite the fact that bornaviruses have an RNA genome, bornavirus sequences integrated into the genomes of several vertebrates millions of years ago. Our hypothesis is that the bank vole, a common wild rodent species in traditional BDV-endemic areas, can serve as a viral host; we therefore explored whether this species can be infected with BDV, and if so, how the virus spreads and whether viral RNA is transcribed into DNA in vivo.We infected neonate bank voles intracerebrally with BDV and euthanized them 2 to 8 weeks post-infection. Specific Ig antibodies were detectable in 41%. Histological evaluation revealed no significant pathological alterations, but BDV RNA and antigen were detectable in all infected brains. Immunohistology demonstrated centrifugal spread throughout the nervous tissue, because viral antigen was widespread in peripheral nerves and ganglia, including the mediastinum, esophagus, and urinary bladder. This was associated with viral shedding in feces, of which 54% were BDV RNA-positive, and urine at 17%. BDV nucleocapsid gene DNA occurred in 66% of the infected voles, and, surprisingly, occasionally also phosphoprotein DNA. Thus, intracerebral BDV infection of bank vole led to systemic infection of the nervous tissue and viral excretion, as well as frequent reverse transcription of the BDV genome, enabling genomic integration. This first experimental bornavirus infection in wild mammals confirms the recent findings regarding bornavirus DNA, and suggests that bank voles are capable of bornavirus transmission.
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Animal models of CNS viral disease: examples from borna disease virus models. Interdiscip Perspect Infect Dis 2010; 2010:709791. [PMID: 20204069 PMCID: PMC2829629 DOI: 10.1155/2010/709791] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Accepted: 12/08/2009] [Indexed: 11/17/2022] Open
Abstract
Borna disease (BD),
caused by the neurotropic RNA virus, Borna
Disease virus, is an affliction ranging from
asymptomatic to fatal meningoencephalitis across
naturally and experimentally infected
warmblooded (mammalian and bird) species. More
than 100 years after the first clinical
descriptions of Borna disease in horses and
studies beginning in the 1980's linking
Borna disease virus to human neuropsychiatric
diseases, experimentally infected rodents have
been used as models for examining behavioral,
neuropharmacological, and neurochemical responses
to viral challenge at different stages of life.
These studies have contributed to understanding
the role of CNS viral injury in vulnerability to
behavioral, developmental, epileptic, and
neurodegenerative diseases and aided evaluation
of the proposed and still controversial links to
human disease.
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Sachs AJ, David SA, Haider NB, Nystuen AM. Patterned neuroprotection in the Inpp4a(wbl) mutant mouse cerebellum correlates with the expression of Eaat4. PLoS One 2009; 4:e8270. [PMID: 20011524 PMCID: PMC2788419 DOI: 10.1371/journal.pone.0008270] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Accepted: 10/05/2009] [Indexed: 12/03/2022] Open
Abstract
The weeble mutant mouse has a frame shift mutation in inositol polyphosphate 4-phosphatase type I (Inpp4a). The phenotype is characterized by an early onset cerebellar ataxia and neurodegeneration, especially apparent in the Purkinje cells. Purkinje cell loss is a common pathological finding in many human and mouse ataxic disorders. Here we show that in the Inpp4awbl mutant, Purkinje cells are lost in a specific temporal and spatial pattern. Loss occurs early in postnatal development; however, prior to the appearance of climbing fibers in the developing molecular layer, the mutant has a normal complement of Purkinje cells and they are properly positioned. Degeneration and reactive gliosis are present at postnatal day 5 and progress rapidly in a defined pattern of patches; however, Inpp4a is expressed uniformly across Purkinje cells. In late stage mutants, patches of surviving Purkinje cells appear remarkably normal with the exception that the climbing fibers have been excessively eliminated. Surviving Purkinje cells express Eaat4, a glutamate transporter that is differentially expressed in subsets of Purkinje cells during development and into adult stages. Prior to Purkinje cell loss, reactive gliosis and dendritic atrophy can be seen in Eaat4 negative stripes. Our data suggest that Purkinje cell loss in the Inpp4awbl mutant is due to glutamate excitotoxicity initiated by the climbing fiber, and that Eaat4 may exert a protective effect.
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Affiliation(s)
- Andrew J. Sachs
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Samuel A. David
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Neena B. Haider
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- * E-mail: (AMN); (NBH)
| | - Arne M. Nystuen
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- * E-mail: (AMN); (NBH)
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Jankowski J, Miething A, Schilling K, Baader SL. Physiological Purkinje Cell Death Is Spatiotemporally Organized in the Developing Mouse Cerebellum. THE CEREBELLUM 2009; 8:277-90. [DOI: 10.1007/s12311-009-0093-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Accepted: 01/05/2009] [Indexed: 02/07/2023]
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Koontz T, Bralic M, Tomac J, Pernjak-Pugel E, Bantug G, Jonjic S, Britt WJ. Altered development of the brain after focal herpesvirus infection of the central nervous system. ACTA ACUST UNITED AC 2008; 205:423-35. [PMID: 18268036 PMCID: PMC2271002 DOI: 10.1084/jem.20071489] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
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.
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Affiliation(s)
- Thad Koontz
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Hippocampal poly(ADP-Ribose) polymerase 1 and caspase 3 activation in neonatal bornavirus infection. J Virol 2007; 82:1748-58. [PMID: 18057239 DOI: 10.1128/jvi.02014-07] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infection of neonatal rats with Borna disease virus results in a characteristic behavioral syndrome and apoptosis of subsets of neurons in the hippocampus, cerebellum, and cortex (neonatal Borna disease [NBD]). In the NBD rat hippocampus, dentate gyrus granule cells progressively degenerate. Apoptotic loss of granule cells in NBD is associated with accumulation of zinc in degenerating neurons and reduced zinc in granule cell mossy fibers. Excess zinc can trigger poly(ADP-ribose) polymerase 1 (PARP-1) activation, and PARP-1 activation can mediate neuronal death. Here, we evaluate hippocampal PARP-1 mRNA and protein expression levels, activation, and cleavage, as well as apoptosis-inducing factor (AIF) nuclear translocation and executioner caspase 3 activation, in NBD rats. PARP-1 mRNA and protein levels were increased in NBD hippocampi. PARP-1 expression and activity were increased in granule cell neurons and glia with enhanced ribosylation of proteins, including PARP-1 itself. In contrast, levels of poly(ADP-ribose) glycohydrolase mRNA were decreased in NBD hippocampi. PARP-1 cleavage and AIF expression were also increased in astrocytes in NBD hippocampi. Levels of activated caspase 3 protein were increased in NBD hippocampi and localized to nuclei, mossy fibers, and dendrites of granule cell neurons. These results implicate aberrant zinc homeostasis, PARP-1, and caspase 3 activation as contributing factors in hippocampal neurodegeneration in NBD.
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