1
|
Pavlou A, Mulenge F, Gern OL, Busker LM, Greimel E, Waltl I, Kalinke U. Orchestration of antiviral responses within the infected central nervous system. Cell Mol Immunol 2024; 21:943-958. [PMID: 38997413 PMCID: PMC11364666 DOI: 10.1038/s41423-024-01181-7] [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: 03/29/2024] [Accepted: 05/05/2024] [Indexed: 07/14/2024] Open
Abstract
Many newly emerging and re-emerging viruses have neuroinvasive potential, underscoring viral encephalitis as a global research priority. Upon entry of the virus into the CNS, severe neurological life-threatening conditions may manifest that are associated with high morbidity and mortality. The currently available therapeutic arsenal against viral encephalitis is rather limited, emphasizing the need to better understand the conditions of local antiviral immunity within the infected CNS. In this review, we discuss new insights into the pathophysiology of viral encephalitis, with a focus on myeloid cells and CD8+ T cells, which critically contribute to protection against viral CNS infection. By illuminating the prerequisites of myeloid and T cell activation, discussing new discoveries regarding their transcriptional signatures, and dissecting the mechanisms of their recruitment to sites of viral replication within the CNS, we aim to further delineate the complexity of antiviral responses within the infected CNS. Moreover, we summarize the current knowledge in the field of virus infection and neurodegeneration and discuss the potential links of some neurotropic viruses with certain pathological hallmarks observed in neurodegeneration.
Collapse
Affiliation(s)
- Andreas Pavlou
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Felix Mulenge
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Olivia Luise Gern
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Lena Mareike Busker
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, 30559, Hannover, Germany
| | - Elisabeth Greimel
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Inken Waltl
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany.
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, 30625, Hannover, Germany.
| |
Collapse
|
2
|
Bröer S, Pauletti A. Microglia and infiltrating macrophages in ictogenesis and epileptogenesis. Front Mol Neurosci 2024; 17:1404022. [PMID: 38873242 PMCID: PMC11171130 DOI: 10.3389/fnmol.2024.1404022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 05/15/2024] [Indexed: 06/15/2024] Open
Abstract
Phagocytes maintain homeostasis in a healthy brain. Upon injury, they are essential for repairing damaged tissue, recruiting other immune cells, and releasing cytokines as the first line of defense. However, there seems to be a delicate balance between the beneficial and detrimental effects of their activation in a seizing brain. Blocking the infiltration of peripheral phagocytes (macrophages) or their depletion can partially alleviate epileptic seizures and prevent the death of neurons in experimental models of epilepsy. However, the depletion of resident phagocytes in the brain (microglia) can aggravate disease outcomes. This review describes the role of resident microglia and peripheral infiltrating monocytes in animal models of acutely triggered seizures and epilepsy. Understanding the roles of phagocytes in ictogenesis and the time course of their activation and involvement in epileptogenesis and disease progression can offer us new biomarkers to identify patients at risk of developing epilepsy after a brain insult, as well as provide novel therapeutic targets for treating epilepsy.
Collapse
Affiliation(s)
- Sonja Bröer
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | | |
Collapse
|
3
|
Costa B, Vale N. Virus-Induced Epilepsy vs. Epilepsy Patients Acquiring Viral Infection: Unravelling the Complex Relationship for Precision Treatment. Int J Mol Sci 2024; 25:3730. [PMID: 38612542 PMCID: PMC11011490 DOI: 10.3390/ijms25073730] [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: 12/07/2023] [Revised: 01/04/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024] Open
Abstract
The intricate relationship between viruses and epilepsy involves a bidirectional interaction. Certain viruses can induce epilepsy by infecting the brain, leading to inflammation, damage, or abnormal electrical activity. Conversely, epilepsy patients may be more susceptible to viral infections due to factors, such as compromised immune systems, anticonvulsant drugs, or surgical interventions. Neuroinflammation, a common factor in both scenarios, exhibits onset, duration, intensity, and consequence variations. It can modulate epileptogenesis, increase seizure susceptibility, and impact anticonvulsant drug pharmacokinetics, immune system function, and brain physiology. Viral infections significantly impact the clinical management of epilepsy patients, necessitating a multidisciplinary approach encompassing diagnosis, prevention, and treatment of both conditions. We delved into the dual dynamics of viruses inducing epilepsy and epilepsy patients acquiring viruses, examining the unique features of each case. For virus-induced epilepsy, we specify virus types, elucidate mechanisms of epilepsy induction, emphasize neuroinflammation's impact, and analyze its effects on anticonvulsant drug pharmacokinetics. Conversely, in epilepsy patients acquiring viruses, we detail the acquired virus, its interaction with existing epilepsy, neuroinflammation effects, and changes in anticonvulsant drug pharmacokinetics. Understanding this interplay advances precision therapies for epilepsy during viral infections, providing mechanistic insights, identifying biomarkers and therapeutic targets, and supporting optimized dosing regimens. However, further studies are crucial to validate tools, discover new biomarkers and therapeutic targets, and evaluate targeted therapy safety and efficacy in diverse epilepsy and viral infection scenarios.
Collapse
Affiliation(s)
- Bárbara Costa
- PerMed Research Group, Center for Health Technology and Services Research (CINTESIS), Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal;
- CINTESIS@RISE, Faculty of Medicine, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
- Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal
| | - Nuno Vale
- PerMed Research Group, Center for Health Technology and Services Research (CINTESIS), Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal;
- CINTESIS@RISE, Faculty of Medicine, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
- Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal
| |
Collapse
|
4
|
DePaula-Silva AB. The Contribution of Microglia and Brain-Infiltrating Macrophages to the Pathogenesis of Neuroinflammatory and Neurodegenerative Diseases during TMEV Infection of the Central Nervous System. Viruses 2024; 16:119. [PMID: 38257819 PMCID: PMC10819099 DOI: 10.3390/v16010119] [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: 12/05/2023] [Revised: 01/06/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
The infection of the central nervous system (CNS) with neurotropic viruses induces neuroinflammation and is associated with the development of neuroinflammatory and neurodegenerative diseases, including multiple sclerosis and epilepsy. The activation of the innate and adaptive immune response, including microglial, macrophages, and T and B cells, while required for efficient viral control within the CNS, is also associated with neuropathology. Under healthy conditions, resident microglia play a pivotal role in maintaining CNS homeostasis. However, during pathological events, such as CNS viral infection, microglia become reactive, and immune cells from the periphery infiltrate into the brain, disrupting CNS homeostasis and contributing to disease development. Theiler's murine encephalomyelitis virus (TMEV), a neurotropic picornavirus, is used in two distinct mouse models: TMEV-induced demyelination disease (TMEV-IDD) and TMEV-induced seizures, representing mouse models of multiple sclerosis and epilepsy, respectively. These murine models have contributed substantially to our understanding of the pathophysiology of MS and seizures/epilepsy following viral infection, serving as critical tools for identifying pharmacological targetable pathways to modulate disease development. This review aims to discuss the host-pathogen interaction during a neurotropic picornavirus infection and to shed light on our current understanding of the multifaceted roles played by microglia and macrophages in the context of these two complexes viral-induced disease.
Collapse
Affiliation(s)
- Ana Beatriz DePaula-Silva
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT 84112, USA
| |
Collapse
|
5
|
Li J, Wang J, Wang H. Emerging Landscape of Preclinical Models for Studying COVID-19 Neurologic Diseases. ACS Pharmacol Transl Sci 2023; 6:1323-1339. [PMID: 37854617 PMCID: PMC10580392 DOI: 10.1021/acsptsci.3c00127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Indexed: 10/20/2023]
Abstract
COVID-19 (Coronavirus Disease 2019) is an infectious disease caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) and has globally infected 768 million people and caused over 6 million deaths. COVID-19 primarily affects the respiratory system but increasing reports of neurologic symptoms associated with COVID-19 have been reported in the literature. The exact mechanism behind COVID-19 neurologic pathophysiology remains poorly understood due to difficulty quantifying clinical neurologic symptoms in humans and correlating them to findings in human post-mortem samples and animal models. Thus, robust preclinical experimental models for COVID-19 neurologic manifestations are urgently needed. Here, we review recent advances in in vitro, in vivo, and other models and technologies for studying COVID-19 including primary cell cultures, pluripotent stem cell-derived neurons and organoids, rodents, nonhuman primates, 3D bioprinting, artificial intelligence, and multiomics. We specifically focus our discussion on the contribution, recent advancements, and limitations these preclinical models have on furthering our understanding of COVID-19's neuropathic physiology. We also discuss these models' roles in the screening and development of therapeutics, vaccines, antiviral drugs, and herbal medicine, and on future opportunities for COVID-19 neurologic research and clinical management.
Collapse
Affiliation(s)
- Jason Li
- Department
of Neurology, Indiana University School
of Medicine, Indianapolis, Indiana 46202, United States
| | - Jing Wang
- Department
of Cellular and Molecular Medicine, University
of California San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Hu Wang
- Institute
of Cell Engineering, School of Medicine, Johns Hopkins University, Baltimore 21215, United States
| |
Collapse
|
6
|
Min S, Gandal MJ, Kopp RF, Liu C, Chen C. No Increased Detection of Nucleic Acids of CNS-related Viruses in the Brains of Patients with Schizophrenia, Bipolar Disorder, and Autism Spectrum Disorder. Schizophr Bull 2023; 49:551-558. [PMID: 36857101 PMCID: PMC10154715 DOI: 10.1093/schbul/sbad003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
BACKGROUND AND HYPOTHESIS Viral infections are increasingly recognized in the etiology of psychiatric disorders based on epidemiological and serological studies. Few studies have analyzed viruses directly within the brain and no comprehensive investigation of viral infection within diseased brains has been completed. This study aims to determine whether viral infection in brain tissues is a risk factor for 3 major psychiatric disorders, including schizophrenia, bipolar disorder, and autism spectrum disorder. STUDY DESIGN This study directly evaluated the presence of viral DNA or RNA in 1569 brains of patients and controls using whole-genome sequencing and RNA sequencing data with 4 independent cohorts. The PathSeq tool was used to identify known human viruses in the genome and transcriptome of patients and controls. STUDY RESULTS A variety of DNA and RNA viruses related to the central nervous system were detected in the brains of patients with major psychiatric disorders, including viruses belonging to Herpesviridae, Polyomaviridae, Retroviridae, Flaviviridae, Parvoviridae, and Adenoviridae. However, no consistent significant differences were found between patients and controls in terms of types and amount of virus detected at both DNA and RNA levels. CONCLUSIONS The findings of this study do not suggest an association between viral infection in postmortem brains and major psychiatric disorders.
Collapse
Affiliation(s)
- Shishi Min
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, and Department of Psychiatry, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Department of Psychiatry, SUNY Upstate Medical University, Syracuse, NY, USA
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Michael J Gandal
- Lifespan Brain Institute at Penn Medicine and The Children’s Hospital of Philadelphia, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, USA
| | - Richard F Kopp
- Department of Psychiatry, SUNY Upstate Medical University, Syracuse, NY, USA
| | - Chunyu Liu
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, and Department of Psychiatry, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Department of Psychiatry, SUNY Upstate Medical University, Syracuse, NY, USA
- School of Psychology, Shaanxi Normal University, Xi’an, Shaanxi, China
| | - Chao Chen
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, and Department of Psychiatry, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, Hunan, China
- National Clinical Research Center on Mental Disorders, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| |
Collapse
|
7
|
Méndez-García LA, Escobedo G, Minguer-Uribe AG, Viurcos-Sanabria R, Aguayo-Guerrero JA, Carrillo-Ruiz JD, Solleiro-Villavicencio H. Role of the renin-angiotensin system in the development of COVID-19-associated neurological manifestations. Front Cell Neurosci 2022; 16:977039. [PMID: 36187294 PMCID: PMC9523599 DOI: 10.3389/fncel.2022.977039] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/26/2022] [Indexed: 01/18/2023] Open
Abstract
SARS-CoV-2 causes COVID-19, which has claimed millions of lives. This virus can infect various cells and tissues, including the brain, for which numerous neurological symptoms have been reported, ranging from mild and non-life-threatening (e.g., headaches, anosmia, dysgeusia, and disorientation) to severe and life-threatening symptoms (e.g., meningitis, ischemic stroke, and cerebral thrombosis). The cellular receptor for SARS-CoV-2 is angiotensin-converting enzyme 2 (ACE2), an enzyme that belongs to the renin-angiotensin system (RAS). RAS is an endocrine system that has been classically associated with regulating blood pressure and fluid and electrolyte balance; however, it is also involved in promoting inflammation, proliferation, fibrogenesis, and lipogenesis. Two pathways constitute the RAS with counter-balancing effects, which is the key to its regulation. The first axis (classical) is composed of angiotensin-converting enzyme (ACE), angiotensin (Ang) II, and angiotensin type 1 receptor (AT1R) as the main effector, which -when activated- increases the production of aldosterone and antidiuretic hormone, sympathetic nervous system tone, blood pressure, vasoconstriction, fibrosis, inflammation, and reactive oxygen species (ROS) production. Both systemic and local classical RAS' within the brain are associated with cognitive impairment, cell death, and inflammation. The second axis (non-classical or alternative) includes ACE2, which converts Ang II to Ang-(1-7), a peptide molecule that activates Mas receptor (MasR) in charge of opposing Ang II/AT1R actions. Thus, the alternative RAS axis enhances cognition, synaptic remodeling, cell survival, cell signal transmission, and antioxidant/anti-inflammatory mechanisms in the brain. In a physiological state, both RAS axes remain balanced. However, some factors can dysregulate systemic and local RAS arms. The binding of SARS-CoV-2 to ACE2 causes the internalization and degradation of this enzyme, reducing its activity, and disrupting the balance of systemic and local RAS, which partially explain the appearance of some of the neurological symptoms associated with COVID-19. Therefore, this review aims to analyze the role of RAS in the development of the neurological effects due to SARS-CoV-2 infection. Moreover, we will discuss the RAS-molecular targets that could be used for therapeutic purposes to treat the short and long-term neurological COVID-19-related sequelae.
Collapse
Affiliation(s)
- Lucía A. Méndez-García
- Laboratory of Immunometabolism, Research Division, General Hospital of Mexico “Dr. Eduardo Liceaga,”Mexico City, Mexico
| | - Galileo Escobedo
- Laboratory of Immunometabolism, Research Division, General Hospital of Mexico “Dr. Eduardo Liceaga,”Mexico City, Mexico
| | - Alan Gerardo Minguer-Uribe
- Laboratory of Molecular Neuropathology, Cellular Physiology Institute, National Autonomous University of Mexico, Mexico City, Mexico
| | - Rebeca Viurcos-Sanabria
- Laboratory of Immunometabolism, Research Division, General Hospital of Mexico “Dr. Eduardo Liceaga,”Mexico City, Mexico
- PECEM, School of Medicine, National Autonomous University of Mexico, Mexico City, Mexico
| | - José A. Aguayo-Guerrero
- Laboratory of Immunometabolism, Research Division, General Hospital of Mexico “Dr. Eduardo Liceaga,”Mexico City, Mexico
| | - José Damián Carrillo-Ruiz
- Research Directorate, General Hospital of Mexico “Dr. Eduardo Liceaga,”Mexico City, Mexico
- Department of Neurology and Neurosurgery, General Hospital of Mexico “Dr. Eduardo Liceaga,”Mexico City, Mexico
- Facultad de Ciencias de la Salud, Universidad Anáhuac, Huixquilucan, Mexico
| | | |
Collapse
|
8
|
Pérez Gómez AA, Karmakar M, Carroll RJ, Lawley KS, Amstalden K, Young CR, Threadgill DW, Welsh CJ, Brinkmeyer-Langford C. Serum Cytokines Predict Neurological Damage in Genetically Diverse Mouse Models. Cells 2022; 11:2044. [PMID: 35805128 PMCID: PMC9265636 DOI: 10.3390/cells11132044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 06/24/2022] [Accepted: 06/24/2022] [Indexed: 12/02/2022] Open
Abstract
Viral infections contribute to neurological and immunological dysfunction driven by complex genetic networks. Theiler's murine encephalomyelitis virus (TMEV) causes neurological dysfunction in mice and can model human outcomes to viral infections. Here, we used genetically distinct mice from five Collaborative Cross mouse strains and C57BL/6J to demonstrate how TMEV-induced immune responses in serum may predict neurological outcomes in acute infection. To test the hypothesis that serum cytokine levels can provide biomarkers for phenotypic outcomes of acute disease, we compared cytokine levels at pre-injection, 4 days post-injection (d.p.i.), and 14 d.p.i. Each strain produced unique baseline cytokine levels and had distinct immune responses to the injection procedure itself. Thus, we eliminated the baseline responses to the injection procedure itself and identified cytokines and chemokines induced specifically by TMEV infection. Then, we identified strain-specific longitudinal cytokine profiles in serum during acute disease. Using stepwise regression analysis, we identified serum immune markers predictive for TMEV-induced neurological phenotypes of the acute phase, e.g., IL-9 for limb paralysis; and TNF-α, IL-1β, and MIP-1β for limb weakness. These findings indicate how temporal differences in immune responses are influenced by host genetic background and demonstrate the potential of serum biomarkers to track the neurological effects of viral infection.
Collapse
Affiliation(s)
- Aracely A. Pérez Gómez
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA;
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA; (K.S.L.); (K.A.); (C.R.Y.); (C.J.W.)
| | - Moumita Karmakar
- Department of Statistics, College of Science, Texas A & M University, College Station, TX 77843, USA; (M.K.); (R.J.C.)
| | - Raymond J. Carroll
- Department of Statistics, College of Science, Texas A & M University, College Station, TX 77843, USA; (M.K.); (R.J.C.)
| | - Koedi S. Lawley
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA; (K.S.L.); (K.A.); (C.R.Y.); (C.J.W.)
| | - Katia Amstalden
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA; (K.S.L.); (K.A.); (C.R.Y.); (C.J.W.)
| | - Colin R. Young
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA; (K.S.L.); (K.A.); (C.R.Y.); (C.J.W.)
| | - David W. Threadgill
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA;
- Department of Molecular and Cellular Medicine, Texas A & M Health Science Center, Texas A & M University, College Station, TX 77843, USA
| | - C. Jane Welsh
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA; (K.S.L.); (K.A.); (C.R.Y.); (C.J.W.)
| | - Candice Brinkmeyer-Langford
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA;
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A & M University, College Station, TX 77843, USA; (K.S.L.); (K.A.); (C.R.Y.); (C.J.W.)
| |
Collapse
|
9
|
Batot G, Metcalf CS, Bell LA, Pauletti A, Wilcox KS, Bröer S. A Model for Epilepsy of Infectious Etiology using Theiler's Murine Encephalomyelitis Virus. J Vis Exp 2022:10.3791/63673. [PMID: 35816000 PMCID: PMC11060116 DOI: 10.3791/63673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024] Open
Abstract
One of the main causes of epilepsy is an infection of the central nervous system (CNS); approximately 8% of patients who survive such an infection develop epilepsy as a consequence, with rates being significantly higher in less economically developed countries. This work provides an overview of modeling epilepsy of infectious etiology and using it as a platform for novel antiseizure compound testing. A protocol of epilepsy induction by non-stereotactic intracerebral injection of Theiler's murine encephalomyelitis virus (TMEV) in C57BL/6 mice is presented, which replicates many of the early and chronic clinical symptoms of viral encephalitis and subsequent epilepsy in human patients. The clinical evaluation of mice during encephalitis to monitor seizure activity and detect the potential antiseizure effects of novel compounds is described. Furthermore, histopathological consequences of viral encephalitis and seizures such as hippocampal damage and neuroinflammation are shown, as well as long-term consequences such as spontaneous epileptic seizures. The TMEV model is one of the first translational, infection-driven, experimental platforms to allow for the investigation of the mechanisms of epilepsy development as a consequence of CNS infection. Thus, it also serves to identify potential therapeutic targets and compounds for patients at risk of developing epilepsy following a CNS infection.
Collapse
Affiliation(s)
- Gaelle Batot
- Department of Pharmacology and Toxicology, University of Utah
| | | | - Laura A Bell
- Department of Pharmacology and Toxicology, University of Utah; Interdepartmental Program in Neuroscience, University of Utah
| | - Alberto Pauletti
- Faculty of Veterinary Medicine, Institute of Pharmacology and Toxicology, Freie Universität Berlin
| | - Karen S Wilcox
- Department of Pharmacology and Toxicology, University of Utah; Interdepartmental Program in Neuroscience, University of Utah
| | - Sonja Bröer
- Faculty of Veterinary Medicine, Institute of Pharmacology and Toxicology, Freie Universität Berlin;
| |
Collapse
|
10
|
Löscher W, Howe CL. Molecular Mechanisms in the Genesis of Seizures and Epilepsy Associated With Viral Infection. Front Mol Neurosci 2022; 15:870868. [PMID: 35615063 PMCID: PMC9125338 DOI: 10.3389/fnmol.2022.870868] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/05/2022] [Indexed: 12/16/2022] Open
Abstract
Seizures are a common presenting symptom during viral infections of the central nervous system (CNS) and can occur during the initial phase of infection ("early" or acute symptomatic seizures), after recovery ("late" or spontaneous seizures, indicating the development of acquired epilepsy), or both. The development of acute and delayed seizures may have shared as well as unique pathogenic mechanisms and prognostic implications. Based on an extensive review of the literature, we present an overview of viruses that are associated with early and late seizures in humans. We then describe potential pathophysiologic mechanisms underlying ictogenesis and epileptogenesis, including routes of neuroinvasion, viral control and clearance, systemic inflammation, alterations of the blood-brain barrier, neuroinflammation, and inflammation-induced molecular reorganization of synapses and neural circuits. We provide clinical and animal model findings to highlight commonalities and differences in these processes across various neurotropic or neuropathogenic viruses, including herpesviruses, SARS-CoV-2, flaviviruses, and picornaviruses. In addition, we extensively review the literature regarding Theiler's murine encephalomyelitis virus (TMEV). This picornavirus, although not pathogenic for humans, is possibly the best-characterized model for understanding the molecular mechanisms that drive seizures, epilepsy, and hippocampal damage during viral infection. An enhanced understanding of these mechanisms derived from the TMEV model may lead to novel therapeutic interventions that interfere with ictogenesis and epileptogenesis, even within non-infectious contexts.
Collapse
Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - Charles L. Howe
- Division of Experimental Neurology, Department of Neurology, Mayo Clinic, Rochester, MN, United States
- Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, MN, United States
| |
Collapse
|
11
|
Morawiec N, Chyra D, Boroń A, Adamczyk B, Jaroszewicz J, Sobala-Szczygieł B, Adamczyk-Sowa M. Bilateral paralysis of peroneal nerve after COVID-19 disease: a case report. BMC Neurol 2022; 22:91. [PMID: 35287619 PMCID: PMC8919171 DOI: 10.1186/s12883-022-02613-5] [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: 04/22/2021] [Accepted: 03/02/2022] [Indexed: 11/24/2022] Open
Abstract
Background COVID-19, caused by a novel coronavirus SARS-CoV 2 has rapidly developed into pandemic. This infectious disease affecting mainly respiratory system may cause multiple systemic disorders. With increasing number of new infected patients there are more and more cases with neurological complications secondary to COVID-19. Case presentation Here we present a case of 67-years old Polish male with previously no comorbidities, who has developed bilateral paralysis of peroneal nerve after SARS-CoV 2 infection. Prior to the hospitalization he presented cough and fever and weakness. RT-PCR was reported positive for COVID-19 infection. Then he developed pneumonia and respiratory failure with bilateral lung consolidations on radiological examination. Laboratory findings revealed elevated levels of D-dimer, CRP, AspAT, GGTP, PCT and serum glucose. After discharge from hospital he was diagnosed with thrombophlebitis and prediabetes on follow-up visits. Due to problems with walking, numbness of toes and involuntary muscle spasms in hands, the patient went to the Neurological Outpatient Clinic. After neurological examination bilateral paralysis of peroneal nerve was revealed. Conclusions In this report we want to highlight one of the unexpected presentations of SARS-CoV 2 infection and emphasize the importance of neurological examination in COVID-19 patients.
Collapse
Affiliation(s)
- Natalia Morawiec
- Department of Neurology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice, ul. 3 Maja 13-15, 41-800, Zabrze, Poland.
| | - Daria Chyra
- Department of Neurology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice, ul. 3 Maja 13-15, 41-800, Zabrze, Poland
| | - Adrianna Boroń
- Department of Neurology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice, ul. 3 Maja 13-15, 41-800, Zabrze, Poland
| | - Bożena Adamczyk
- Department of Neurology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice, ul. 3 Maja 13-15, 41-800, Zabrze, Poland
| | - Jerzy Jaroszewicz
- Department of Infectious Diseases and Hepatology, Medical University of Silesia in Katowice, ul. Aleja Legionów 49, 41-902, Bytom, Poland
| | - Barbara Sobala-Szczygieł
- Department of Infectious Diseases and Hepatology, Medical University of Silesia in Katowice, ul. Aleja Legionów 49, 41-902, Bytom, Poland
| | - Monika Adamczyk-Sowa
- Department of Neurology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia in Katowice, ul. 3 Maja 13-15, 41-800, Zabrze, Poland
| |
Collapse
|
12
|
DePaula-Silva AB, Bell LA, Wallis GJ, Wilcox KS. Inflammation Unleashed in Viral-Induced Epileptogenesis. Epilepsy Curr 2021; 21:433-440. [PMID: 34924851 PMCID: PMC8652320 DOI: 10.1177/15357597211040939] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Viral infection of the central nervous system increasingly places people at risk of developing life-threatening and treatment-resistant acute and chronic seizures (epilepsy). The emergence of new human viruses due to ongoing social, political, and ecological changes places people at risk more than ever before. The development of new preventative or curative strategies is critical to address this burden. However, our understanding of the complex relationship between viruses and the brain has been hindered by the lack of animal models that survive the initial infection and are amenable for long-term mechanistic, behavioral, and pharmacological studies in the process of viral-induced epileptogenesis. In this review, we focus on the Theiler’s murine encephalomyelitis virus (TMEV) mouse model of viral infection–induced epilepsy. The TMEV model has a number of important advantages to address the quintessential processes underlying the development of epilepsy following a viral infection, as well as fuel new therapeutic development. In this review, we highlight the contributions of the TMEV model to our current understanding of the relationship between viral infection, inflammation, and seizures.
Collapse
Affiliation(s)
| | - Laura A. Bell
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA
| | - Glenna J. Wallis
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA
| | - Karen S. Wilcox
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA
- Karen S. Wilcox, PhD, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT 84112, USA.
| |
Collapse
|
13
|
C-type lectin receptor DCIR contributes to hippocampal injury in acute neurotropic virus infection. Sci Rep 2021; 11:23819. [PMID: 34893671 PMCID: PMC8664856 DOI: 10.1038/s41598-021-03201-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 11/26/2021] [Indexed: 11/16/2022] Open
Abstract
Neurotropic viruses target the brain and contribute to neurologic diseases. C-type lectin receptors (CLRs) are pattern recognition receptors that recognize carbohydrate structures on endogenous molecules and pathogens. The myeloid CLR dendritic cell immunoreceptor (DCIR) is expressed by antigen presenting cells and mediates inhibitory intracellular signalling. To investigate the effect of DCIR on neurotropic virus infection, mice were infected experimentally with Theiler’s murine encephalomyelitis virus (TMEV). Brain tissue of TMEV-infected C57BL/6 mice and DCIR−/− mice were analysed by histology, immunohistochemistry and RT-qPCR, and spleen tissue by flow cytometry. To determine the impact of DCIR deficiency on T cell responses upon TMEV infection in vitro, antigen presentation assays were utilised. Genetic DCIR ablation in C57BL/6 mice was associated with an ameliorated hippocampal integrity together with reduced cerebral cytokine responses and reduced TMEV loads in the brain. Additionally, absence of DCIR favoured increased peripheral cytotoxic CD8+ T cell responses following TMEV infection. Co-culture experiments revealed that DCIR deficiency enhances the activation of antigen-specific CD8+ T cells by virus-exposed dendritic cells (DCs), indicated by increased release of interleukin-2 and interferon-γ. Results suggest that DCIR deficiency has a supportive influence on antiviral immune mechanisms, facilitating virus control in the brain and ameliorates neuropathology during acute neurotropic virus infection.
Collapse
|
14
|
Du Y, Zhao W, Du L, Liu J. Neuropsychiatric symptoms associated with the COVID-19 and its potential nervous system infection mechanism: the role of imaging in the study. PSYCHORADIOLOGY 2021; 1:199-211. [PMID: 38666221 PMCID: PMC10917188 DOI: 10.1093/psyrad/kkab019] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/07/2021] [Accepted: 12/01/2021] [Indexed: 04/28/2024]
Abstract
The epidemic of coronavirus disease 2019 (COVID-19) has broken the normal spread mode of respiratory viruses, namely, mainly spread in winter, resulting in over 230 million confirmed cases of COVID-19. Many studies have shown that severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can affect the nervous system by varying degrees. In this review, we look at the acute neuropsychiatric impacts of COVID-19 patients, including acute ischemic stroke, encephalitis, acute necrotizing encephalopathy, dysosmia, and epilepsy, as well as the long-term neuropsychiatric sequelae of COVID-19 survivors: mental disorder and neurodegenerative diseases. In particular, this review discusses long-term changes in brain structure and function associated with COVID-19 infection. We believe that the traditional imaging sequences are important in the acute phase, while the nontraditional imaging sequences are more meaningful for the detection of long-term neuropsychiatric sequelae. These long-term follow-up changes in structure and function may also help us understand the causes of neuropsychiatric symptoms in COVID-19 survivors. Finally, we review previous studies and discuss some potential mechanisms of SARS-CoV-2 infection in the nervous system. Continuous focus on neuropsychiatric sequelae and a comprehensive understanding of the long-term impacts of the virus to the nervous system is significant for formulating effective sequelae prevention and management strategies, and may provide important clues for nervous system damage in future public health crises.
Collapse
Affiliation(s)
- Yanyao Du
- Department of Radiology, Second Xiangya Hospital of Central South University, Changsha 410011, Hunan Province, China
| | - Wei Zhao
- Department of Radiology, Second Xiangya Hospital of Central South University, Changsha 410011, Hunan Province, China
- Clinical Research Center for Medical Imaging in Hunan Province, Changsha 410011, Hunan, China
| | - Lei Du
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati 45255, OH, USA
| | - Jun Liu
- Department of Radiology, Second Xiangya Hospital of Central South University, Changsha 410011, Hunan Province, China
- Clinical Research Center for Medical Imaging in Hunan Province, Changsha 410011, Hunan, China
- Department of Radiology Quality Control Center, Hunan Province, Changsha 410011, Hunan, China
| |
Collapse
|
15
|
Bohmwald K, Andrade CA, Gálvez NMS, Mora VP, Muñoz JT, Kalergis AM. The Causes and Long-Term Consequences of Viral Encephalitis. Front Cell Neurosci 2021; 15:755875. [PMID: 34916908 PMCID: PMC8668867 DOI: 10.3389/fncel.2021.755875] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/01/2021] [Indexed: 12/15/2022] Open
Abstract
Reports regarding brain inflammation, known as encephalitis, have shown an increasing frequency during the past years. Encephalitis is a relevant concern to public health due to its high morbidity and mortality. Infectious or autoimmune diseases are the most common cause of encephalitis. The clinical symptoms of this pathology can vary depending on the brain zone affected, with mild ones such as fever, headache, confusion, and stiff neck, or severe ones, such as seizures, weakness, hallucinations, and coma, among others. Encephalitis can affect individuals of all ages, but it is frequently observed in pediatric and elderly populations, and the most common causes are viral infections. Several viral agents have been described to induce encephalitis, such as arboviruses, rhabdoviruses, enteroviruses, herpesviruses, retroviruses, orthomyxoviruses, orthopneumovirus, and coronaviruses, among others. Once a neurotropic virus reaches the brain parenchyma, the resident cells such as neurons, astrocytes, and microglia, can be infected, promoting the secretion of pro-inflammatory molecules and the subsequent immune cell infiltration that leads to brain damage. After resolving the viral infection, the local immune response can remain active, contributing to long-term neuropsychiatric disorders, neurocognitive impairment, and degenerative diseases. In this article, we will discuss how viruses can reach the brain, the impact of viral encephalitis on brain function, and we will focus especially on the neurocognitive sequelae reported even after viral clearance.
Collapse
Affiliation(s)
- Karen Bohmwald
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Catalina A Andrade
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás M S Gálvez
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Valentina P Mora
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José T Muñoz
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexis M Kalergis
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| |
Collapse
|
16
|
Pavasutthipaisit S, Stoff M, Ebbecke T, Ciurkiewicz M, Mayer-Lambertz S, Störk T, Pavelko KD, Lepenies B, Beineke A. CARD9 Deficiency Increases Hippocampal Injury Following Acute Neurotropic Picornavirus Infection but Does Not Affect Pathogen Elimination. Int J Mol Sci 2021; 22:ijms22136982. [PMID: 34209576 PMCID: PMC8268812 DOI: 10.3390/ijms22136982] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/20/2021] [Accepted: 06/25/2021] [Indexed: 12/11/2022] Open
Abstract
Neurotropic viruses target the brain and contribute to neurologic diseases. Caspase recruitment domain containing family member 9 (CARD9) controls protective immunity in a variety of infectious disorders. To investigate the effect of CARD9 in neurotropic virus infection, CARD9−/− and corresponding C57BL/6 wild-type control mice were infected with Theiler’s murine encephalomyelitis virus (TMEV). Brain tissue was analyzed by histology, immunohistochemistry and molecular analyses, and spleens by flow cytometry. To determine the impact of CARD9 deficiency on T cell responses in vitro, antigen presentation assays were utilized. Genetic ablation of CARD9 enhanced early pro-inflammatory cytokine responses and accelerated infiltration of T and B cells in the brain, together with a transient increase in TMEV-infected cells in the hippocampus. CARD9−/− mice showed an increased loss of neuronal nuclear protein+ mature neurons and doublecortin+ neuronal precursor cells and an increase in β-amyloid precursor protein+ damaged axons in the hippocampus. No effect of CARD9 deficiency was found on the initiation of CD8+ T cell responses by flow cytometry and co-culture experiments using virus-exposed dendritic cells or microglia-enriched glial cell mixtures, respectively. The present study indicates that CARD9 is dispensable for the initiation of early antiviral responses and TMEV elimination but may contribute to the modulation of neuroinflammation, thereby reducing hippocampal injury following neurotropic virus infection.
Collapse
Affiliation(s)
- Suvarin Pavasutthipaisit
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Department of Pathology, Faculty of Veterinary Medicine, Mahanakorn University of Technology, Bangkok 10530, Thailand
| | - Melanie Stoff
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
| | - Tim Ebbecke
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Institute for Immunology and Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Malgorzata Ciurkiewicz
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
| | - Sabine Mayer-Lambertz
- Institute for Immunology and Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Theresa Störk
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
| | - Kevin D. Pavelko
- Department of Immunology, Mayo Clinic, Rochester, MN 55905, USA;
| | - Bernd Lepenies
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Institute for Immunology and Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Correspondence: ; Tel.: +49-51-195-38640
| |
Collapse
|
17
|
Zhang R, Mu J, Chi J, Jiang W, Chi X. The role of picornavirus infection in epileptogenesis. ACTA EPILEPTOLOGICA 2021. [DOI: 10.1186/s42494-021-00040-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractPicornaviridae are a family of small positive-strand RNA viruses, and transmitted via the respiratory or fecal-oral route. The neurotropic picornaviruses can induce acute or late recurrent seizures following central nervous system infection, by infecting the peripheral nerve, crossing the blood-brain barrier and migrating in the Trojan-horse method. Theiler’s murine encephalomyelitis virus (TMEV), as a member of Picornaviridae family, can cause encephalitis, leading to chronic spontaneous seizures. TMEV-infected C57BL/6 mice have been used as an animal model for exploring the mechanism of epileptogenesis and assessing new antiepileptic drugs. Astrogliosis, neuronal death and microglial recruitment have been detected in the hippocampus following the picornaviruse-induced encephalitis. The macrophages, monocytes, neutrophils, as well as IL-6 and TNF-α released by them, play an important role in the epileptogenesis. In this review, we summarize the clinical characteristics of picornavirus infection, and the immunopathology involved in the TMEV-induced epilepsy.
Collapse
|
18
|
Bell LA, Wallis GJ, Wilcox KS. Reactivity and increased proliferation of NG2 cells following central nervous system infection with Theiler's murine encephalomyelitis virus. J Neuroinflammation 2020; 17:369. [PMID: 33272299 PMCID: PMC7713670 DOI: 10.1186/s12974-020-02043-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 11/24/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Neuron-glial antigen 2 (NG2) cells are a glial cell type tiled throughout the gray and white matter of the central nervous system (CNS). NG2 cells are known for their ability to differentiate into oligodendrocytes and are commonly referred to as oligodendrocyte precursor cells. However, recent investigations have begun to identify additional functions of NG2 cells in CNS health and pathology. NG2 cells form physical and functional connections with neurons and other glial cell types throughout the CNS, allowing them to monitor and respond to the neural environment. Growing evidence indicates that NG2 cells become reactive under pathological conditions, though their specific roles are only beginning to be elucidated. While reactive microglia and astrocytes are well-established contributors to neuroinflammation and the development of epilepsy following CNS infection, the dynamics of NG2 cells remain unclear. Therefore, we investigated NG2 cell reactivity in a viral-induced mouse model of temporal lobe epilepsy. METHODS C57BL6/J mice were injected intracortically with Theiler's murine encephalomyelitis virus (TMEV) or PBS. Mice were graded twice daily for seizures between 3 and 7 days post-injection (dpi). At 4 and 14 dpi, brains were fixed and stained for NG2, the microglia/macrophage marker IBA1, and the proliferation marker Ki-67. Confocal z stacks were acquired in both the hippocampus and the overlying cortex. Total field areas stained by each cell marker and total field area of colocalized pixels between NG2 and Ki67 were compared between groups. RESULTS Both NG2 cells and microglia/macrophages displayed increased immunoreactivity and reactive morphologies in the hippocampus of TMEV-injected mice. While increased immunoreactivity for IBA1 was also present in the cortex, there was no significant change in NG2 immunoreactivity in the cortex following TMEV infection. Colocalization analysis for NG2 and Ki-67 revealed a significant increase in overlap between NG2 and Ki-67 in the hippocampus of TMEV-injected mice at both time points, but no significant differences in cortex. CONCLUSIONS NG2 cells acquire a reactive phenotype and proliferate in response to TMEV infection. These results suggest that NG2 cells alter their function in response to viral encephalopathy, making them potential targets to prevent the development of epilepsy following viral infection.
Collapse
Affiliation(s)
- Laura A Bell
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, 84112, USA
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, 84112, USA
| | - Glenna J Wallis
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Karen S Wilcox
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, 84112, USA.
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, 84112, USA.
| |
Collapse
|
19
|
Hassanzadeh K, Perez Pena H, Dragotto J, Buccarello L, Iorio F, Pieraccini S, Sancini G, Feligioni M. Considerations around the SARS-CoV-2 Spike Protein with Particular Attention to COVID-19 Brain Infection and Neurological Symptoms. ACS Chem Neurosci 2020; 11:2361-2369. [PMID: 32627524 PMCID: PMC7374936 DOI: 10.1021/acschemneuro.0c00373] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 07/06/2020] [Indexed: 12/22/2022] Open
Abstract
Spike protein (S protein) is the virus "key" to infect cells and is able to strongly bind to the human angiotensin-converting enzyme2 (ACE2), as has been reported. In fact, Spike structure and function is known to be highly important for cell infection as well as for entering the brain. Growing evidence indicates that different types of coronaviruses not only affect the respiratory system, but they might also invade the central nervous system (CNS). However, very little evidence has been so far reported on the presence of COVID-19 in the brain, and the potential exploitation, by this virus, of the lung to brain axis to reach neurons has not been completely understood. In this Article, we assessed the SARS-CoV and SARS-CoV-2 Spike protein sequence, structure, and electrostatic potential using computational approaches. Our results showed that the S proteins of SARS-CoV-2 and SARS-CoV are highly similar, sharing a sequence identity of 77%. In addition, we found that the SARS-CoV-2 S protein is slightly more positively charged than that of SARS-CoV since it contains four more positively charged residues and five less negatively charged residues which may lead to an increased affinity to bind to negatively charged regions of other molecules through nonspecific and specific interactions. Analysis the S protein binding to the host ACE2 receptor showed a 30% higher binding energy for SARS-CoV-2 than for the SARS-CoV S protein. These results might be useful for understanding the mechanism of cell entry, blood-brain barrier crossing, and clinical features related to the CNS infection by SARS-CoV-2.
Collapse
Affiliation(s)
- Kambiz Hassanzadeh
- Laboratory of Neuronal Cell Signaling,
EBRI Rita Levi-Montalcini Foundation, Rome 00161,
Italy
- Cellular and Molecular Research Center, Research
Institute for Health Development, Kurdistan University of Medical
Sciences, Sanandaj 66177-13446, Iran
| | - Helena Perez Pena
- Department of Chemistry and National Inter-University
Consortium for Materials Science and Technology-INSTM-UdR Milano, University
of Milan, Milan 20133, Italy
| | - Jessica Dragotto
- Laboratory of Neuronal Cell Signaling,
EBRI Rita Levi-Montalcini Foundation, Rome 00161,
Italy
| | - Lucia Buccarello
- Laboratory of Neuronal Cell Signaling,
EBRI Rita Levi-Montalcini Foundation, Rome 00161,
Italy
| | - Federico Iorio
- Laboratory of Neuronal Cell Signaling,
EBRI Rita Levi-Montalcini Foundation, Rome 00161,
Italy
| | - Stefano Pieraccini
- Department of Chemistry and National Inter-University
Consortium for Materials Science and Technology-INSTM-UdR Milano, University
of Milan, Milan 20133, Italy
- Institute of Science and Chemical
Technology “Giulio Natta”, Milan 20133,
Italy
| | - Giulio Sancini
- Human Physiology Lab, School of Medicine and Surgery,
University of Milano-Bicocca, Via Cadore 48, 20900 Monza,
Italy
| | - Marco Feligioni
- Laboratory of Neuronal Cell Signaling,
EBRI Rita Levi-Montalcini Foundation, Rome 00161,
Italy
- Department of Neurorehabilitation Sciences, Casa
di Cura del Policlinico, Milan 20144, Italy
| |
Collapse
|
20
|
Niazkar HR, Zibaee B, Nasimi A, Bahri N. The neurological manifestations of COVID-19: a review article. Neurol Sci 2020; 41:1667-1671. [PMID: 32483687 PMCID: PMC7262683 DOI: 10.1007/s10072-020-04486-3] [Citation(s) in RCA: 173] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/21/2020] [Indexed: 12/28/2022]
Abstract
RESULTS Various neurological manifestations have been reported in the literature associated with COVID-19, which in the current study are classified into Central Nervous System (CNS) related manifestations including headache, dizziness, impaired consciousness, acute cerebrovascular disease, epilepsy, and Peripheral Nervous System (PNS) related manifestations such as hyposmia/anosmia, hypogeusia/ageusia, muscle pain, and Guillain-Barre syndrome. CONCLUSION During the current context of COVID-19 pandemic, physicians should be aware of wide spectrum of neurological COVID-19 sign and symptoms for early diagnosis and isolation of patients. In this regard, COVID-19 has been associated with many neurological manifestations such as confusion, anosmia, and ageusia. Also, various evidences support the possible CNS roles in the COVID-19 pathophysiology. In this regard, further investigation of CNS involvement of SARS-COV-2 is suggested.
Collapse
Affiliation(s)
- Hamid Reza Niazkar
- Student Research Committee, Faculty of Medicine, Gonabad University of Medical Sciences, Gonabad, Iran
| | - Behdad Zibaee
- Student Research Committee, Faculty of Medicine, Gonabad University of Medical Sciences, Gonabad, Iran
| | - Ali Nasimi
- Student Research Committee, Faculty of Medicine, Gonabad University of Medical Sciences, Gonabad, Iran
| | - Narjes Bahri
- Department of Midwifery, Faculty of Medicine, Social Development and Health Promotion Research Center, Gonabad University of Medical Sciences, Gonabad, Iran
| |
Collapse
|
21
|
Elgamasy S, Kamel MG, Ghozy S, Khalil A, Morra ME, Islam SMS. First case of focal epilepsy associated with SARS-coronavirus-2. J Med Virol 2020; 92:2238-2242. [PMID: 32484990 PMCID: PMC7300744 DOI: 10.1002/jmv.26113] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 05/27/2020] [Accepted: 05/28/2020] [Indexed: 12/31/2022]
Abstract
A healthy patient presented to Klinikum Altmühlfranken Weißenburg Hospital, Germany, with two morning attacks of painful muscle spasm in the left upper and lower limbs, without altered consciousness. Full examinations, radiological imaging, electroencephalography, lumbar puncture, and autoimmune profile were either normal or not consistent with patient's complaint. Subsequent epileptic episodes were observed on admission day and the following days; thus, the patient was diagnosed with focal epilepsy. The patient started to develop a fever and severe cough on day 4, and SARS‐coronavirus‐2 was confirmed through a nasopharyngeal swap. She received anticonvulsants and symptomatic treatments and completely recovered. This report emphasizes the potential nervous system involvement in severe acute respiratory syndrome‐coronavirus‐2 pathogenesis. Coronaviruses are serious pathogens that infect respiratory, gastrointestinal, and central nervous systems. SARS‐CoV‐2 may have neuroinvasive and neurotropic potential as some patients have demonstrated neurologic symptoms. Neurologic manifestations may occur early in the infection course of SARS‐CoV‐2.
Collapse
Affiliation(s)
- Sara Elgamasy
- Department of Internal MedicineKlinikum Altmühlfranken WeißenburgBayernGermany
| | | | - Sherief Ghozy
- Faculty of MedicineMansoura UniversityMansouraEgypt
- Neurosurgery DepartmentEl Sheikh Zayed Specialized HospitalGizaEgypt
| | - Adham Khalil
- Faculty of MedicineZagazig UniversityZagazigEgypt
| | | | - Sheikh M. S. Islam
- School of Exercise and Nutrition Sciences, Institute for Physical Activity and Nutrition (IPAN)Deakin UniversityMelbourneAustralia
| |
Collapse
|
22
|
Frequent Convulsive Seizures in an Adult Patient with COVID-19: A Case Report. IRANIAN RED CRESCENT MEDICAL JOURNAL 2020. [DOI: 10.5812/ircmj.102828] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
23
|
DePaula-Silva AB, Gorbea C, Doty DJ, Libbey JE, Sanchez JMS, Hanak TJ, Cazalla D, Fujinami RS. Differential transcriptional profiles identify microglial- and macrophage-specific gene markers expressed during virus-induced neuroinflammation. J Neuroinflammation 2019; 16:152. [PMID: 31325960 PMCID: PMC6642742 DOI: 10.1186/s12974-019-1545-x] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 07/10/2019] [Indexed: 01/09/2023] Open
Abstract
Background In the healthy central nervous system (CNS), microglia are found in a homeostatic state and peripheral macrophages are absent from the brain. Microglia play key roles in maintaining CNS homeostasis and acting as first responders to infection and inflammation, and peripheral macrophages infiltrate the CNS during neuroinflammation. Due to their distinct origins and functions, discrimination between these cell populations is essential to the comprehension of neuroinflammatory disorders. Studies comparing the gene profiles of microglia and peripheral macrophages, or macrophages in vitro-derived from bone marrow, under non-infectious conditions of the CNS, have revealed valuable microglial-specific genes. However, studies comparing gene profiles between CNS-infiltrating macrophages and microglia, when both are isolated from the CNS during viral-induced neuroinflammation, are lacking. Methods We isolated, via flow cytometry, microglia and infiltrating macrophages from the brains of Theiler’s murine encephalomyelitis virus-infected C57BL/6 J mice and used RNA-Seq, followed by validation with qPCR, to examine the differential transcriptional profiles of these cells. We utilized primary literature defining subcellular localization to determine whether or not particular proteins extracted from the transcriptional profiles were expressed at the cell surface. The surface expression and cellular specificity of triggering receptor expressed on myeloid cells 1 (TREM-1) protein were examined via flow cytometry. We also examined the immune response gene profile within the transcriptional profiles of these isolated microglia and infiltrating macrophages. Results We have identified and validated new microglial- and macrophage-specific genes, encoding cell surface proteins, expressed at the peak of neuroinflammation. TREM-1 protein was confirmed to be expressed by infiltrating macrophages, not microglia, at the peak of neuroinflammation. We also identified both unique and redundant immune functions, through examination of the immune response gene profiles, of microglia and infiltrating macrophages during neurotropic viral infection. Conclusions The differential expression of cell surface-specific genes during neuroinflammation can potentially be used to discriminate between microglia and macrophages as well as provide a resource that can be further utilized to target and manipulate specific cell responses during neuroinflammation. Electronic supplementary material The online version of this article (10.1186/s12974-019-1545-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Ana Beatriz DePaula-Silva
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Carlos Gorbea
- Department of Biochemistry, University of Utah, 15 North Medical Drive East, 4100 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Daniel J Doty
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - John Michael S Sanchez
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Tyler J Hanak
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Demián Cazalla
- Department of Biochemistry, University of Utah, 15 North Medical Drive East, 4100 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA.
| |
Collapse
|
24
|
Gerhauser I, Hansmann F, Ciurkiewicz M, Löscher W, Beineke A. Facets of Theiler's Murine Encephalomyelitis Virus-Induced Diseases: An Update. Int J Mol Sci 2019; 20:ijms20020448. [PMID: 30669615 PMCID: PMC6358740 DOI: 10.3390/ijms20020448] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 01/15/2019] [Accepted: 01/18/2019] [Indexed: 12/31/2022] Open
Abstract
Theiler’s murine encephalomyelitis virus (TMEV), a naturally occurring, enteric pathogen of mice is a Cardiovirus of the Picornaviridae family. Low neurovirulent TMEV strains such as BeAn cause a severe demyelinating disease in susceptible SJL mice following intracerebral infection. Furthermore, TMEV infections of C57BL/6 mice cause acute polioencephalitis initiating a process of epileptogenesis that results in spontaneous recurrent epileptic seizures in approximately 50% of affected mice. Moreover, C3H mice develop cardiac lesions after an intraperitoneal high-dose application of TMEV. Consequently, TMEV-induced diseases are widely used as animal models for multiple sclerosis, epilepsy, and myocarditis. The present review summarizes morphological lesions and pathogenic mechanisms triggered by TMEV with a special focus on the development of hippocampal degeneration and seizures in C57BL/6 mice as well as demyelination in the spinal cord in SJL mice. Furthermore, a detailed description of innate and adaptive immune responses is given. TMEV studies provide novel insights into the complexity of organ- and mouse strain-specific immunopathology and help to identify factors critical for virus persistence.
Collapse
Affiliation(s)
- Ingo Gerhauser
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
| | - Florian Hansmann
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
- Center for System Neuroscience, 30559 Hannover, Germany.
| | - Malgorzata Ciurkiewicz
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
- Center for System Neuroscience, 30559 Hannover, Germany.
| | - Wolfgang Löscher
- Center for System Neuroscience, 30559 Hannover, Germany.
- Department of Pharmacology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
- Center for System Neuroscience, 30559 Hannover, Germany.
| |
Collapse
|
25
|
Waltl I, Käufer C, Gerhauser I, Chhatbar C, Ghita L, Kalinke U, Löscher W. Microglia have a protective role in viral encephalitis-induced seizure development and hippocampal damage. Brain Behav Immun 2018; 74:186-204. [PMID: 30217535 PMCID: PMC7111316 DOI: 10.1016/j.bbi.2018.09.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 08/23/2018] [Accepted: 09/06/2018] [Indexed: 12/12/2022] Open
Abstract
In the central nervous system (CNS), innate immune surveillance is mainly coordinated by microglia. These CNS resident myeloid cells are assumed to help orchestrate the immune response against infections of the brain. However, their specific role in this process and their interactions with CNS infiltrating immune cells, such as blood-borne monocytes and T cells are only incompletely understood. The recent development of PLX5622, a specific inhibitor of colony-stimulating factor 1 receptor that depletes microglia, allows studying the role of microglia in conditions of brain injury such as viral encephalitis, the most common form of brain infection. Here we used this inhibitor in a model of viral infection-induced epilepsy, in which C57BL/6 mice are infected by a picornavirus (Theiler's murine encephalomyelitis virus) and display seizures and hippocampal damage. Our results show that microglia are required early after infection to limit virus distribution and persistence, most likely by modulating T cell activation. Microglia depletion accelerated the occurrence of seizures, exacerbated hippocampal damage, and led to neurodegeneration in the spinal cord, which is normally not observed in this mouse strain. This study enhances our understanding of the role of microglia in viral encephalitis and adds to the concept of microglia-T cell crosstalk.
Collapse
Affiliation(s)
- Inken Waltl
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany,Center for Systems Neuroscience, Hannover, Germany
| | - Christopher Käufer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Ingo Gerhauser
- Department of Pathology, University of Veterinary Medicine Hannover, Germany
| | - Chintan Chhatbar
- Institute for Experimental Infection Research, TWINCORE, Center for Experimental and Clinical Infection Research, a Joint Venture Between the Helmholtz Center for Infection Research, Braunschweig, and the Hannover Medical School, Hannover, Germany
| | - Luca Ghita
- Institute for Experimental Infection Research, TWINCORE, Center for Experimental and Clinical Infection Research, a Joint Venture Between the Helmholtz Center for Infection Research, Braunschweig, and the Hannover Medical School, Hannover, Germany
| | - Ulrich Kalinke
- Center for Systems Neuroscience, Hannover, Germany,Institute for Experimental Infection Research, TWINCORE, Center for Experimental and Clinical Infection Research, a Joint Venture Between the Helmholtz Center for Infection Research, Braunschweig, and the Hannover Medical School, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
26
|
Anjum SMM, Käufer C, Hopfengärtner R, Waltl I, Bröer S, Löscher W. Automated quantification of EEG spikes and spike clusters as a new read out in Theiler's virus mouse model of encephalitis-induced epilepsy. Epilepsy Behav 2018; 88:189-204. [PMID: 30292054 DOI: 10.1016/j.yebeh.2018.09.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/13/2018] [Accepted: 09/16/2018] [Indexed: 12/17/2022]
Abstract
Intracerebral infection of C57BL/6 mice with Theiler's murine encephalomyelitis virus (TMEV) replicates many features of viral encephalitis-induced epilepsy in humans, including neuroinflammation, early (insult-associated) and late (spontaneous) seizures, neurodegeneration in the hippocampus, and cognitive and behavioral alterations. Thus, this model may be ideally suited to study mechanisms involved in encephalitis-induced epilepsy as potential targets for epilepsy prevention. However, spontaneous recurrent seizures (SRS) occur too infrequently to be useful as a biomarker of epilepsy, e.g., for drug studies. This prompted us to evaluate whether epileptiform spikes or spike clusters in the cortical electroencephalogram (EEG) may be a useful surrogate of epilepsy in this model. For this purpose, we developed an algorithm that allows efficient and large-scale EEG analysis of early and late seizures, spikes, and spike clusters in the EEG. While 77% of the infected mice exhibited early seizures, late seizures were only observed in 33% of the animals. The clinical characteristics of early and late seizures did not differ except that late generalized convulsive (stage 5) seizures were significantly longer than early stage 5 seizures. Furthermore, the frequency of SRS was much lower than the frequency of early seizures. Continuous (24/7) video-EEG monitoring over several months following infection indicated that the latent period to onset of SRS was 61 (range 16-91) days. Spike and spike clusters were significantly more frequent in infected mice with late seizures than in infected mice without seizures or in mock-infected sham controls. Based on the results of this study, increases in EEG spikes and spike clusters in groups of infected mice may be used as a new readout for studies on antiepileptogenic or disease-modifying drug effects in this model, because the significant increase in average spike counts in mice with late seizures obviously indicates a proepileptogenic alteration.
Collapse
Affiliation(s)
- Syed Muhammad Muneeb Anjum
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Christopher Käufer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | | | - Inken Waltl
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Sonja Bröer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
27
|
Hanak TJ, Libbey JE, Doty DJ, Sim JT, DePaula-Silva AB, Fujinami RS. Positive modulation of mGluR5 attenuates seizures and reduces TNF-α + macrophages and microglia in the brain in a murine model of virus-induced temporal lobe epilepsy. Exp Neurol 2018; 311:194-204. [PMID: 30316834 DOI: 10.1016/j.expneurol.2018.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 09/12/2018] [Accepted: 10/10/2018] [Indexed: 12/29/2022]
Abstract
Viral encephalitis markedly increases the risk for the development of epilepsy. The Theiler's murine encephalomyelitis virus (TMEV)-induced model of seizures/epilepsy is a murine model of both viral-induced seizures/epilepsy and human Temporal Lobe Epilepsy. The inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α have been shown to play a role in seizure development in the TMEV-induced model of seizures/epilepsy, and infiltrating macrophages along with microglia have been shown to be major producers of these cytokines. The metabotropic glutamate receptor 5 (mGluR5) is a G-protein coupled receptor that has been shown to reduce IL-6 and TNF-α and to provide neuroprotection in other disease models. Therefore, we hypothesized that stimulation of mGluR5 would not only reduce seizures but attenuate IL-6 and TNF-α production in microglia and macrophages in the TMEV model. We found that pharmacological stimulation of mGluR5 with the selective positive allosteric modulator VU0360172 not only reduced acute seizure outcomes, but also reduced the percent of microglia and macrophages producing TNF-α 3 days post infection. Furthermore, treatment with VU0360172 did not alter the level of viral antigen, compared to controls, showing that this treatment does not compromise viral clearance. These results establish that mGluR5 may represent a therapeutic target in the TMEV-induced model of seizures/epilepsy.
Collapse
Affiliation(s)
- Tyler J Hanak
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA; Interdepartmental Program in Neuroscience, University of Utah, 20 South 2030 East, Salt Lake City, UT 84112, USA
| | - Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Daniel J Doty
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Jordan T Sim
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Ana Beatriz DePaula-Silva
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA.
| |
Collapse
|
28
|
Chemokine receptors CCR2 and CX3CR1 regulate viral encephalitis-induced hippocampal damage but not seizures. Proc Natl Acad Sci U S A 2018; 115:E8929-E8938. [PMID: 30181265 PMCID: PMC6156634 DOI: 10.1073/pnas.1806754115] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Viral encephalitis is a major risk factor for the development of seizures, epilepsy, and hippocampal damage with associated cognitive impairment, markedly reducing quality of life in survivors. The mechanisms underlying seizures and hippocampal neurodegeneration developing during and after viral encephalitis are only incompletely understood, hampering the development of preventive treatments. Recent findings suggest that brain invasion of blood-born monocytes may be critically involved in both seizures and brain damage in response to encephalitis, whereas the relative role of microglia, the brain's resident immune cells, in these processes is not clear. CCR2 and CX3CR1 are two chemokine receptors that regulate the responses of myeloid cells, such as monocytes and microglia, during inflammation. We used Ccr2-KO and Cx3cr1-KO mice to understand the role of these receptors in viral encephalitis-associated seizures and neurodegeneration, using the Theiler's virus model of encephalitis in C57BL/6 mice. Our results show that CCR2 as well as CX3CR1 plays a key role in the accumulation of myeloid cells in the CNS and activation of hippocampal myeloid cells upon infection. Furthermore, by using Cx3cr1-creER+/-tdTomatoSt/Wt reporter mice, we show that, with regard to CD45 and CD11b expression, some microglia become indistinguishable from monocytes during CNS infection. Interestingly, the lack of CCR2 or CX3CR1 receptors was associated with almost complete prevention of hippocampal damage but did not prevent seizure development after viral CNS infection. These data are compatible with the hypothesis that CNS inflammatory mechanism(s) other than the infiltrating myeloid cells trigger the development of seizures during viral encephalitis.
Collapse
|
29
|
DePaula-Silva AB, Sonderegger FL, Libbey JE, Doty DJ, Fujinami RS. The immune response to picornavirus infection and the effect of immune manipulation on acute seizures. J Neurovirol 2018; 24:464-477. [PMID: 29687406 PMCID: PMC6105529 DOI: 10.1007/s13365-018-0636-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/09/2018] [Accepted: 03/27/2018] [Indexed: 12/23/2022]
Abstract
Viral infection of the central nervous system can result in encephalitis. About 20% of individuals who develop viral encephalitis go on to develop epilepsy. We have established an experimental model where virus infection of mice with Theiler's murine encephalomyelitis virus (TMEV) leads to acute seizures, followed by a latent period (no seizures/epileptogenesis phase) and then spontaneous recurrent seizures-epilepsy. Infiltrating macrophages (CD11b+CD45hi) present in the brain at day 3 post-infection are an important source of interleukin-6, which contributes to the development of acute seizures in the TMEV-induced seizure model. Time course analysis of viral infection and inflammatory [CD11b+CD45hiLy-6Chi] and patrolling [CD11b+CD45hiLy-6Clow] monocyte and T cell infiltration into the brains of TMEV-infected C57BL/6J mice over the entire course of the acute viral infection was performed to elucidate the role of virus and the immune response to virus in seizures and viral clearance. The infiltrating inflammatory macrophages were present early following infection but declined over the course of acute viral infection, supporting a role in seizure development, while the lymphocyte infiltration increased rapidly and plateaued, advocating that they play a role in viral clearance. In addition, we showed for the first time that, while TMEV infection of RAG1-/- mice did not alter the number of mice experiencing acute seizures, TMEV infection of C57BL/6J mice depleted of macrophages resulted in a significant decrease in the number of mice experiencing seizures, again supporting a role for infiltrating macrophages in the development of acute seizures in the TMEV-induced seizure model.
Collapse
Affiliation(s)
| | | | - Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Daniel J Doty
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA.
| |
Collapse
|
30
|
Bartolini L, Libbey JE, Ravizza T, Fujinami RS, Jacobson S, Gaillard WD. Viral Triggers and Inflammatory Mechanisms in Pediatric Epilepsy. Mol Neurobiol 2018; 56:1897-1907. [PMID: 29978423 DOI: 10.1007/s12035-018-1215-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/27/2018] [Indexed: 12/21/2022]
Abstract
Experimental and clinical findings suggest a crucial role for inflammation in the onset of pediatric seizures; this mechanism is not targeted by conventional antiepileptic drugs and may contribute to refractory epilepsy. Several triggers, including infection with neurotropic viruses such as human herpesvirus 6 (HHV-6), other herpesviruses, and picornaviruses, appear to induce activation of the innate and adaptive immune systems, which results in several neuroinflammatory responses, leading to enhanced neuronal excitability, and ultimately contributing to epileptogenesis. This review discusses the proposed mechanisms by which infection with herpesviruses, and particularly with HHV-6, and ensuing inflammation may lead to seizure generation, and later development of epilepsy. We also examine the evidence that links herpesvirus and picornavirus infections with acute seizures and chronic forms of epilepsy. Understanding the mechanisms by which specific viruses may trigger a cascade of alterations in the CNS ultimately leading to epilepsy appears critical for the development of therapeutic agents that may target the virus or inflammatory mechanisms early and prevent progression of epileptogenesis.
Collapse
Affiliation(s)
- Luca Bartolini
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, NIH, Building 10, room 7-5680, 10 Center Drive, Bethesda, MD, 20814, USA. .,Division of Neuroimmunology and Neurovirology, National Institute of Neurological Disorders and Stroke, NIH, 10 Center Drive, Bethesda, MD, 20892, USA. .,Center for Neuroscience, Children's National Medical Center, George Washington University, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Teresa Ravizza
- Neuroscience Department, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Via La Masa 19, 20156, Milan, Italy
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Steven Jacobson
- Division of Neuroimmunology and Neurovirology, National Institute of Neurological Disorders and Stroke, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - William D Gaillard
- Center for Neuroscience, Children's National Medical Center, George Washington University, 111 Michigan Ave NW, Washington, DC, 20010, USA
| |
Collapse
|
31
|
Uhde AK, Ciurkiewicz M, Herder V, Khan MA, Hensel N, Claus P, Beckstette M, Teich R, Floess S, Baumgärtner W, Jung K, Huehn J, Beineke A. Intact interleukin-10 receptor signaling protects from hippocampal damage elicited by experimental neurotropic virus infection of SJL mice. Sci Rep 2018; 8:6106. [PMID: 29666403 PMCID: PMC5904160 DOI: 10.1038/s41598-018-24378-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 03/27/2018] [Indexed: 12/24/2022] Open
Abstract
Theiler’s murine encephalomyelitis virus (TMEV) infection represents an experimental mouse model to study hippocampal damage induced by neurotropic viruses. IL-10 is a pleiotropic cytokine with profound anti-inflammatory properties, which critically controls immune homeostasis. In order to analyze IL-10R signaling following virus-induced polioencephalitis, SJL mice were intracerebrally infected with TMEV. RNA-based next generation sequencing revealed an up-regulation of Il10, Il10rα and further genes involved in IL-10 downstream signaling, including Jak1, Socs3 and Stat3 in the brain upon infection. Subsequent antibody-mediated blockade of IL-10R signaling led to enhanced hippocampal damage with neuronal loss and increased recruitment of CD3+ T cells, CD45R+ B cells and an up-regulation of Il1α mRNA. Increased expression of Tgfβ and Foxp3 as well as accumulation of Foxp3+ regulatory T cells and arginase-1+ macrophages/microglia was detected in the hippocampus, representing a potential compensatory mechanism following disturbed IL-10R signaling. Additionally, an increased peripheral Chi3l3 expression was found in spleens of infected mice, which may embody reactive regulatory mechanisms for prevention of excessive immunopathology. The present study highlights the importance of IL-10R signaling for immune regulation and its neuroprotective properties in the context of an acute neurotropic virus infection.
Collapse
Affiliation(s)
- Ann-Kathrin Uhde
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Malgorzata Ciurkiewicz
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Vanessa Herder
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Muhammad Akram Khan
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany.,Department of Pathobiology, Faculty of Veterinary & Animal Sciences, PMAS-Arid Agriculture University, Rawalpindi, Pakistan
| | - Niko Hensel
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany
| | - Peter Claus
- Center for Systems Neuroscience, Hannover, Germany.,Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,Niedersachsen-Research Network on Neuroinfectiology (N-RENNT), Hannover, Germany
| | - Michael Beckstette
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - René Teich
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Stefan Floess
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany.,Niedersachsen-Research Network on Neuroinfectiology (N-RENNT), Hannover, Germany
| | - Klaus Jung
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Jochen Huehn
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany. .,Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
32
|
Abstract
Epilepsy, characterized by spontaneous recurrent seizures (SRS), is a serious and common neurological disorder afflicting an estimated 1% of the population worldwide. Animal experiments, especially those utilizing small laboratory rodents, remain essential to understanding the fundamental mechanisms underlying epilepsy and to prevent, diagnose, and treat this disease. While much attention has been focused on epileptogenesis in animal models of epilepsy, there is little discussion on SRS, the hallmark of epilepsy. This is in part due to the technical difficulties of rigorous SRS detection. In this review, we comprehensively summarize both genetic and acquired models of SRS and discuss the methodology used to monitor and detect SRS in mice and rats.
Collapse
Affiliation(s)
- Bin Gu
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC 27599, USA.
| | - Katherine A Dalton
- Psychology & Neuroscience Program, University of North Carolina, Chapel Hill, NC 27599, USA
| |
Collapse
|
33
|
Becker AJ. Review: Animal models of acquired epilepsy: insights into mechanisms of human epileptogenesis. Neuropathol Appl Neurobiol 2018; 44:112-129. [DOI: 10.1111/nan.12451] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 10/27/2017] [Indexed: 02/06/2023]
Affiliation(s)
- A. J. Becker
- Section for Translational Epilepsy Research; Department of Neuropathology; University of Bonn Medical Center; Bonn Germany
| |
Collapse
|
34
|
Zhan J, Lin TH, Libbey JE, Sun P, Ye Z, Song C, Wallendorf M, Gong H, Fujinami RS, Song SK. Diffusion Basis Spectrum and Diffusion Tensor Imaging Detect Hippocampal Inflammation and Dendritic Injury in a Virus-Induced Mouse Model of Epilepsy. Front Neurosci 2018; 12:77. [PMID: 29497358 PMCID: PMC5818459 DOI: 10.3389/fnins.2018.00077] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 01/30/2018] [Indexed: 01/08/2023] Open
Abstract
Hippocampal CA1 inflammation and dendritic loss are common in epilepsy. Quantitative detection of coexisting brain inflammation and injury could be beneficial in monitoring disease progression and assessing therapeutic efficacy. In this work, we used conventional diffusion tensor imaging (DTI, known to detect axonal injury and demyelination) and a novel diffusion basis spectrum imaging (DBSI, known to detect axonal injury, demyelination, and inflammation) to detect hippocampal CA1 lesions resulting from neuronal dendritic injury/loss and concomitant inflammation in Theiler's murine encephalomyelitis virus (TMEV)-induced seizure mice. Following the cross-sectional ex vivo diffusion magnetic resonance imaging measurements, immunohistochemistry was performed to validate DTI and DBSI findings. Both DTI and DBSI detected immunohistochemistry-confirmed dendritic injury in the hippocampal CA1 region. Additionally, DBSI-derived restricted isotropic diffusion tensor fraction correlated with 4',6-diamidine-2'-phenylindole dihydrochloride (DAPI)-positive nucleus counts, and DBSI-derived fiber fraction correlated with dendrite density assessed by microtubule-associated protein 2 staining. DTI-derived fractional anisotropy (FA) correlated with dendrite density and negatively correlated with DAPI-positive nucleus counts. Although both DTI and DBSI detected hippocampal injury/inflammation, DTI-FA was less specific than DBSI-derived pathological metrics for hippocampal CA1 dendritic injury and inflammation in TMEV-induced seizure mice.
Collapse
Affiliation(s)
- Jie Zhan
- Department of Radiology, the First Affiliated Hospital, Nanchang University, Jiangxi, China.,Department of Radiology, Washington University in St. Louis, St. Louis, MO, United States
| | - Tsen-Hsuan Lin
- Department of Radiology, Washington University in St. Louis, St. Louis, MO, United States
| | - Jane E Libbey
- Department of Pathology, University of Utah, Salt Lake City, UT, United States
| | - Peng Sun
- Department of Radiology, Washington University in St. Louis, St. Louis, MO, United States
| | - Zezhong Ye
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, United States
| | - Chunyu Song
- Department of Biomedical Engineering, Washington University, St. Louis, MO, United States
| | - Michael Wallendorf
- Department of Biostatistics, Washington University in St. Louis, St. Louis, MO, United States
| | - Honghan Gong
- Department of Radiology, the First Affiliated Hospital, Nanchang University, Jiangxi, China
| | - Robert S Fujinami
- Department of Pathology, University of Utah, Salt Lake City, UT, United States
| | - Sheng-Kwei Song
- Department of Radiology, Washington University in St. Louis, St. Louis, MO, United States.,Department of Biomedical Engineering, Washington University, St. Louis, MO, United States.,Hope Center for Neurological Disorders, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, United States
| |
Collapse
|
35
|
Macrophage depletion by liposome-encapsulated clodronate suppresses seizures but not hippocampal damage after acute viral encephalitis. Neurobiol Dis 2017; 110:192-205. [PMID: 29208406 DOI: 10.1016/j.nbd.2017.12.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 11/09/2017] [Accepted: 12/01/2017] [Indexed: 12/12/2022] Open
Abstract
Viral encephalitis is a major risk factor for the development of seizures and epilepsy, but the underlying mechanisms are only poorly understood. Mouse models such as viral encephalitis induced by intracerebral infection with Theiler's virus in C57BL/6 (B6) mice allow advancing our understanding of the immunological and virological aspects of infection-induced seizures and their treatment. Previous studies using the Theiler's virus model in B6 mice have indicated that brain-infiltrating inflammatory macrophages and the cytokines released by these cells are key to the development of acute seizures and hippocampal damage in this model. However, approaches used to prevent or reduce macrophage infiltration were not specific, so contribution of other mechanisms could not be excluded. In the present study, we used a more selective and widely used approach for macrophage depletion, i.e., systemic administration of clodronate liposomes, to study the contribution of macrophage infiltration to development of seizures and hippocampal damage. By this approach, almost complete depletion of monocytic cells was achieved in spleen and blood of Theiler's virus infected B6 mice, which was associated with a 70% decrease in the number of brain infiltrating macrophages as assessed by flow cytometry. Significantly less clodronate liposome-treated mice exhibited seizures than liposome controls (P<0.01), but the development of hippocampal damage was not prevented or reduced. Clodronate liposome treatment did not reduce the increased Iba1 and Mac3 labeling in the hippocampus of infected mice, indicating that activated microglia may contribute to hippocampal damage. The unexpected mismatch between occurrence of seizures and hippocampal damage is thought-provoking and suggests that the mechanisms involved in degeneration of specific populations of hippocampal neurons in encephalitis-induced epilepsy are more complex than previously thought.
Collapse
|
36
|
Löscher W, Ferland RJ, Ferraro TN. The relevance of inter- and intrastrain differences in mice and rats and their implications for models of seizures and epilepsy. Epilepsy Behav 2017; 73. [PMID: 28651171 PMCID: PMC5909069 DOI: 10.1016/j.yebeh.2017.05.040] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
It is becoming increasingly clear that the genetic background of mice and rats, even in inbred strains, can have a profound influence on measures of seizure susceptibility and epilepsy. These differences can be capitalized upon through genetic mapping studies to reveal genes important for seizures and epilepsy. However, strain background and particularly mixed genetic backgrounds of transgenic animals need careful consideration in both the selection of strains and in the interpretation of results and conclusions. For instance, mice with targeted deletions of genes involved in epilepsy can have profoundly disparate phenotypes depending on the background strain. In this review, we discuss findings related to how this genetic heterogeneity has and can be utilized in the epilepsy field to reveal novel insights into seizures and epilepsy. Moreover, we discuss how caution is needed in regards to rodent strain or even animal vendor choice, and how this can significantly influence seizure and epilepsy parameters in unexpected ways. This is particularly critical in decisions regarding the strain of choice used in generating mice with targeted deletions of genes. Finally, we discuss the role of environment (at vendor and/or laboratory) and epigenetic factors for inter- and intrastrain differences and how such differences can affect the expression of seizures and the animals' performance in behavioral tests that often accompany acute and chronic seizure testing.
Collapse
Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| | - Russell J Ferland
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, NY, United States; Department of Neurology, Albany Medical College, Albany, NY, United States
| | - Thomas N Ferraro
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| |
Collapse
|
37
|
Cusick MF, Libbey JE, Doty DJ, DePaula-Silva AB, Fujinami RS. The role of peripheral interleukin-6 in the development of acute seizures following virus encephalitis. J Neurovirol 2017; 23:696-703. [PMID: 28741149 DOI: 10.1007/s13365-017-0554-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 06/26/2017] [Accepted: 07/10/2017] [Indexed: 02/02/2023]
Abstract
Seizure disorders are often associated with infectious etiologies. Infection, via the intracerebral (i.c.) route, of C57BL/6J mice with the Daniels (DA) strain of Theiler's murine encephalomyelitis virus (TMEV) results in approximately 50% of the mice developing acute behavioral seizures. TMEV-DA is the wild-type strain of the virus that replicates within the parenchyma of the brain. A variant of TMEV-DA, TMEV-H101, does not replicate within the parenchyma of the brain. However, infection with TMEV-H101 via the i.c. route still results in approximately 40% of the mice developing acute behavioral seizures. Infiltrating macrophages producing interleukin-6 (IL-6) have been implicated in the induction of acute seizures following TMEV-DA infection. We examined macrophage infiltration and microglial activation within the brain and cytokine levels in the periphery in mice infected with TMEV-DA or TMEV-H101 and assessed the effects of the addition of recombinant IL-6 to the periphery in wild-type and IL-6 knockout mice infected with TMEV-DA. We found that pathologic levels of IL-6 in the periphery may play a role in the development of seizures when viral replication within the brain is limited. Examination of the role played by the peripheral immune system in the development of seizures/epilepsy in the TMEV-induced seizure model, the first viral infection driven model for epilepsy, could lead to the elucidation of novel therapeutics.
Collapse
Affiliation(s)
- Matthew F Cusick
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA.,Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Daniel J Doty
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Ana Beatriz DePaula-Silva
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA.
| |
Collapse
|
38
|
Libbey JE, Cusick MF, Doty DJ, Fujinami RS. Complement Components Are Expressed by Infiltrating Macrophages/Activated Microglia Early Following Viral Infection. Viral Immunol 2017; 30:304-314. [PMID: 28402228 DOI: 10.1089/vim.2016.0175] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The individual innate immune components, interleukin-6 and complement component C3, play a role in the development of acute seizures in the Theiler's murine encephalomyelitis virus-induced seizure model. We examined the mRNA expression of various other complement components, cytokines, chemokines, and major histocompatibility complex antigens both within brain and in isolated ramified microglial and infiltrating macrophage/activated microglial cell populations over a time course covering the first 3 days postinfection. We found that complement component C3 showed the greatest increase in expression in brain of all of the complement components assayed and its level of expression was higher in infiltrating macrophages/activated microglia than in ramified microglial cells.
Collapse
Affiliation(s)
- Jane E Libbey
- Department of Pathology, University of Utah School of Medicine , Salt Lake City, Utah
| | - Matthew F Cusick
- Department of Pathology, University of Utah School of Medicine , Salt Lake City, Utah
| | - Daniel J Doty
- Department of Pathology, University of Utah School of Medicine , Salt Lake City, Utah
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine , Salt Lake City, Utah
| |
Collapse
|
39
|
Animal Models of Seizures and Epilepsy: Past, Present, and Future Role for the Discovery of Antiseizure Drugs. Neurochem Res 2017; 42:1873-1888. [PMID: 28290134 DOI: 10.1007/s11064-017-2222-z] [Citation(s) in RCA: 207] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/01/2017] [Accepted: 03/02/2017] [Indexed: 12/14/2022]
Abstract
The identification of potential therapeutic agents for the treatment of epilepsy requires the use of seizure models. Except for some early treatments, including bromides and phenobarbital, the antiseizure activity of all clinically used drugs was, for the most part, defined by acute seizure models in rodents using the maximal electroshock and subcutaneous pentylenetetrazole seizure tests and the electrically kindled rat. Unfortunately, the clinical evidence to date would suggest that none of these models, albeit useful, are likely to identify those therapeutics that will effectively manage patients with drug resistant seizures. Over the last 30 years, a number of animal models have been developed that display varying degrees of pharmacoresistance, such as the phenytoin- or lamotrigine-resistant kindled rat, the 6-Hz mouse model of partial seizures, the intrahippocampal kainate model in mice, or rats in which spontaneous recurrent seizures develops after inducing status epilepticus by chemical or electrical stimulation. As such, these models can be used to study mechanisms of drug resistance and may provide a unique opportunity for identifying a truly novel antiseizure drug (ASD), but thus far clinical evidence for this hope is lacking. Although animal models of drug resistant seizures are now included in ASD discovery approaches such as the ETSP (epilepsy therapy screening program), it is important to note that no single model has been validated for use to identify potential compounds for as yet drug resistant seizures, but rather a battery of such models should be employed, thus enhancing the sensitivity to discover novel, highly effective ASDs. The present review describes the previous and current approaches used in the search for new ASDs and offers some insight into future directions incorporating new and emerging animal models of therapy resistance.
Collapse
|
40
|
DePaula-Silva AB, Hanak TJ, Libbey JE, Fujinami RS. Theiler's murine encephalomyelitis virus infection of SJL/J and C57BL/6J mice: Models for multiple sclerosis and epilepsy. J Neuroimmunol 2017; 308:30-42. [PMID: 28237622 DOI: 10.1016/j.jneuroim.2017.02.012] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 02/01/2017] [Accepted: 02/10/2017] [Indexed: 10/20/2022]
Abstract
Mouse models are great tools to study the mechanisms of disease development. Theiler's murine encephalomyelitis virus is used in two distinct viral infection mouse models to study the human diseases multiple sclerosis (MS) and epilepsy. Intracerebral (i.c.) infection of the SJL/J mouse strain results in persistent viral infection of the central nervous system and a MS-like disease, while i.c. infection of the C57BL/6J mouse strain results in acute seizures and epilepsy. Our understanding of how the immune system contributes to the development of two disparate diseases caused by the same virus is presented.
Collapse
Affiliation(s)
- Ana Beatriz DePaula-Silva
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Tyler J Hanak
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA.
| |
Collapse
|
41
|
Viral mouse models of multiple sclerosis and epilepsy: Marked differences in neuropathogenesis following infection with two naturally occurring variants of Theiler's virus BeAn strain. Neurobiol Dis 2016; 99:121-132. [PMID: 28017800 DOI: 10.1016/j.nbd.2016.12.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 11/24/2016] [Accepted: 12/20/2016] [Indexed: 01/03/2023] Open
Abstract
Following intracerebral inoculation, the BeAn 8386 strain of Theiler's virus causes persistent infection and inflammatory demyelinating encephalomyelitis in the spinal cord of T-cell defective SJL/J mice, which is widely used as a model of multiple sclerosis. In contrast, C57BL/6 (B6) mice clear the virus and develop inflammation and lesions in the hippocampus, associated with acute and chronic seizures, representing a novel model of viral encephalitis-induced epilepsy. Here we characterize the geno- and phenotype of two naturally occurring variants of BeAn (BeAn-1 and BeAn-2) that can be used to further understand the viral and host factors involved in the neuropathogenesis in B6 and SJL/J mice. Next generation sequencing disclosed 15 single nucleotide differences between BeAn-1 and BeAn-2, of which 4 are coding changes and 3 are in the 5'-UTR (5'-untranslated region). The relatively minor variations in the nucleotide sequence of the two BeAn substrains led to marked differences in neurovirulence. In SJL/J mice, inflammatory demyelination in the spinal cord and its clinical consequences were significantly more marked following infection with BeAn-1 than with BeAn-2. Both BeAn substrains caused lymphocyte infiltration and increase of MAC3-positive cells in the hippocampus, but hippocampal damage and seizures were only observed in B6 mice. Seizures occurred in one third of BeAn-2 infected B6 mice, but not in BeAn-1 infected B6 mice. By comparing individual mice by receiver operating characteristic (ROC) curve analysis, the severity of hippocampal neurodegeneration and amount of MAC3-positive microglia/macrophages discriminated seizing from non-seizing B6 mice, whereas T-lymphocyte brain infiltration was not found to be a crucial factor. These data add novel evidence to the view that differential outcome of infection may be not invariably linked to a distinct viral burden but to a finely tuned balance between antiviral immune responses that although essential for host resistance can also contribute to immunopathology.
Collapse
|
42
|
Dupuis N, Mazarati A, Desnous B, Chhor V, Fleiss B, Le Charpentier T, Lebon S, Csaba Z, Gressens P, Dournaud P, Auvin S. Pro-epileptogenic effects of viral-like inflammation in both mature and immature brains. J Neuroinflammation 2016; 13:307. [PMID: 27955671 PMCID: PMC5153898 DOI: 10.1186/s12974-016-0773-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 12/03/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Infectious encephalitides are most often associated with acute seizures during the infection period and are risk factors for the development of epilepsy at later times. Mechanisms of viral encephalitis-induced epileptogenesis are poorly understood. Here, we evaluated the contribution of viral encephalitis-associated inflammation to ictogenesis and epileptogenesis using a rapid kindling protocol in rats. In addition, we examined whether minocycline can improve outcomes of viral-like brain inflammation. METHODS To produce viral-like inflammation, polyinosinic-polycytidylic acid (PIC), a toll-like receptor 3 (TLR3) agonist, was applied to microglial/macrophage cell cultures and to the hippocampus of postnatal day 13 (P13) and postnatal day 74 (P74) rats. Cell cultures permit the examination of the inflammation induced by PIC, while the in vivo setting better suits the analysis of cytokine production and the effects of inflammation on epileptogenesis. Minocycline (50 mg/kg) was injected intraperitoneally for 3 consecutive days prior to the kindling procedure to evaluate its effects on inflammation and epileptogenesis. RESULTS PIC injection facilitated kindling epileptogenesis, which was evident as an increase in the number of full limbic seizures at both ages. Furthermore, in P14 rats, we observed a faster seizure onset and prolonged retention of the kindling state. PIC administration also led to an increase in interleukin 1β (IL-1β) levels in the hippocampus in P14 and P75 rats. Treatment with minocycline reversed neither the pro-epileptogenic effects of PIC nor the increase of IL-1β in the hippocampus in both P14 and P75 rats. CONCLUSIONS Hippocampal injection of PIC facilitates rapid kindling epileptogenesis at both P14 and P75, suggesting that viral-induced inflammation increases epileptogenesis irrespective of brain maturation. Minocycline, however, was unable to reverse the increase of epileptogenesis, which might be linked to its absence of effect on hippocampal IL-1β levels at both ages.
Collapse
Affiliation(s)
- Nina Dupuis
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
| | - Andrey Mazarati
- Department of Pediatrics, Neurology division and Children’s Discovery and Innovation Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095 USA
| | - Béatrice Desnous
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
- AP-HP, Hôpital Robert Debré, Service de Neurologie Pédiatrique, 75019 Paris, France
| | - Vibol Chhor
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
| | - Bobbi Fleiss
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
| | - Tifenn Le Charpentier
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
| | - Sophie Lebon
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
| | - Zsolt Csaba
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
| | - Pierre Gressens
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
- AP-HP, Hôpital Robert Debré, Service de Neurologie Pédiatrique, 75019 Paris, France
| | - Pascal Dournaud
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
| | - Stéphane Auvin
- INSERM, U1141, 75019 Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, INSERM UMR1141, 75019 Paris, France
- AP-HP, Hôpital Robert Debré, Service de Neurologie Pédiatrique, 75019 Paris, France
| |
Collapse
|
43
|
Tsunoda I, Sato F, Omura S, Fujita M, Sakiyama N, Park AM. Three immune-mediated disease models induced by Theiler's virus: Multiple sclerosis, seizures and myocarditis. CLINICAL & EXPERIMENTAL NEUROIMMUNOLOGY 2016; 7:330-345. [PMID: 28603559 PMCID: PMC5464738 DOI: 10.1111/cen3.12341] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Theiler's murine encephalomyelitis virus (TMEV) infection has been used as a viral model for multiple sclerosis (MS), as TMEV can induce chronic inflammatory demyelinating lesions with viral persistence in the spinal cord of SJL/J mice. In contrast, when C57BL/6 mice are infected with TMEV, the mice can clear the virus from the central nervous system (CNS), without viral persistence or demyelination, but develop seizures and hippocampal sclerosis, which has been used as a viral model for seizures/epilepsy. In the two TMEV-induced CNS disease models, not only viral infection, but also immune responses contribute to the pathogenesis. Interestingly, acquired immunity plays an effector role in the MS model, whereas innate immunity appears to contribute to the development of seizures. Recently, we have established the third TMEV-induced disease model, a mouse model for viral myocarditis, using C3H mice. TMEV-induced myocarditis is a triphasic disease, which mimics human myocarditis; phase I, mediated by viral replication in the heart and innate immunity; phase II, mediated by acquired immunity; and phase III, resulted from cardiac fibrosis. The genetic susceptibility to the aforementioned three models (MS, seizures and myocarditis) differs among mouse strains. We have compared and contrasted the three models induced by one single pathogen, TMEV, particularly in regard to the roles of T helper cells and natural killer T cells, which will give an insight into how interactions between the immune system and the host's genetic background determine the tissue tropism of virus and the development of virus-induced organ-specific immunopathology.
Collapse
Affiliation(s)
- Ikuo Tsunoda
- Department of Microbiology, Kindai University Faculty of Medicine, Osakasayama, Osaka, Japan
| | - Fumitaka Sato
- Department of Microbiology, Kindai University Faculty of Medicine, Osakasayama, Osaka, Japan
| | - Seiichi Omura
- Department of Microbiology, Kindai University Faculty of Medicine, Osakasayama, Osaka, Japan
| | - Mitsugu Fujita
- Department of Microbiology, Kindai University Faculty of Medicine, Osakasayama, Osaka, Japan
| | - Namie Sakiyama
- Department of Microbiology, Kindai University Faculty of Medicine, Osakasayama, Osaka, Japan
| | - Ah-Mee Park
- Department of Microbiology, Kindai University Faculty of Medicine, Osakasayama, Osaka, Japan
| |
Collapse
|
44
|
Fit for purpose application of currently existing animal models in the discovery of novel epilepsy therapies. Epilepsy Res 2016; 126:157-84. [PMID: 27505294 DOI: 10.1016/j.eplepsyres.2016.05.016] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 03/06/2016] [Accepted: 05/30/2016] [Indexed: 01/10/2023]
Abstract
Animal seizure and epilepsy models continue to play an important role in the early discovery of new therapies for the symptomatic treatment of epilepsy. Since 1937, with the discovery of phenytoin, almost all anti-seizure drugs (ASDs) have been identified by their effects in animal models, and millions of patients world-wide have benefited from the successful translation of animal data into the clinic. However, several unmet clinical needs remain, including resistance to ASDs in about 30% of patients with epilepsy, adverse effects of ASDs that can reduce quality of life, and the lack of treatments that can prevent development of epilepsy in patients at risk following brain injury. The aim of this review is to critically discuss the translational value of currently used animal models of seizures and epilepsy, particularly what animal models can tell us about epilepsy therapies in patients and which limitations exist. Principles of translational medicine will be used for this discussion. An essential requirement for translational medicine to improve success in drug development is the availability of animal models with high predictive validity for a therapeutic drug response. For this requirement, the model, by definition, does not need to be a perfect replication of the clinical condition, but it is important that the validation provided for a given model is fit for purpose. The present review should guide researchers in both academia and industry what can and cannot be expected from animal models in preclinical development of epilepsy therapies, which models are best suited for which purpose, and for which aspects suitable models are as yet not available. Overall further development is needed to improve and validate animal models for the diverse areas in epilepsy research where suitable fit for purpose models are urgently needed in the search for more effective treatments.
Collapse
|
45
|
Brandt C, Rankovic V, Töllner K, Klee R, Bröer S, Löscher W. Refinement of a model of acquired epilepsy for identification and validation of biomarkers of epileptogenesis in rats. Epilepsy Behav 2016; 61:120-131. [PMID: 27343814 DOI: 10.1016/j.yebeh.2016.05.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/09/2016] [Accepted: 05/12/2016] [Indexed: 01/23/2023]
Abstract
In rodent models in which status epilepticus (SE) is used to induce epilepsy, typically most animals develop spontaneous recurrent seizures (SRS). The SE duration for induction of epileptogenesis depends on the type of SE induction. In models with electrical SE induction, the minimum duration of SE to induce epileptogenesis in >90% of animals ranges from 3-4h. A high incidence of epilepsy is an advantage in the search of antiepileptogenic treatments, whereas it is a disadvantage in the search for biomarkers of epileptogenesis, because it does not allow a comparison of potential biomarkers in animals that either develop or do not develop epilepsy. The aim of this project was the refinement of an established SE rat model so that only ~50% of the animals develop epilepsy. For this purpose, we used an electrical model of SE induction, in which a self-sustained SE develops after prolonged stimulation of the basolateral amygdala. Previous experiments had shown that the majority of rats develop SRS after 4-h SE in this model so that the SE reduced duration to 2.5h by administering diazepam. This resulted in epilepsy development in only 50% of rats, thus reaching the goal of the project. The latent period to onset of SRS wa s >2weeks in most rats. Development of epilepsy could be predicted in most rats by behavioral hyperexcitability, whereas seizure threshold did not differentiate rats that did and did not develop SRS. The refined SE model may offer a platform to identify and validate biomarkers of epileptogenesis.
Collapse
Affiliation(s)
- Claudia Brandt
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; Center for Systems Neuroscience, 30559 Hannover, Germany
| | - Vladan Rankovic
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; Center for Systems Neuroscience, 30559 Hannover, Germany
| | - Kathrin Töllner
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; Center for Systems Neuroscience, 30559 Hannover, Germany
| | - Rebecca Klee
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; Center for Systems Neuroscience, 30559 Hannover, Germany
| | - Sonja Bröer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; Center for Systems Neuroscience, 30559 Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; Center for Systems Neuroscience, 30559 Hannover, Germany.
| |
Collapse
|
46
|
Libbey JE, Hanak TJ, Doty DJ, Wilcox KS, Fujinami RS. NBQX, a highly selective competitive antagonist of AMPA and KA ionotropic glutamate receptors, increases seizures and mortality following picornavirus infection. Exp Neurol 2016; 280:89-96. [PMID: 27072529 DOI: 10.1016/j.expneurol.2016.04.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/25/2016] [Accepted: 04/08/2016] [Indexed: 12/15/2022]
Abstract
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.
Collapse
Affiliation(s)
- Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Tyler J Hanak
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Daniel J Doty
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA
| | - Karen S Wilcox
- Department of Pharmacology & Toxicology, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT 84112, USA.
| |
Collapse
|
47
|
Loewen JL, Barker-Haliski ML, Dahle EJ, White HS, Wilcox KS. Neuronal Injury, Gliosis, and Glial Proliferation in Two Models of Temporal Lobe Epilepsy. J Neuropathol Exp Neurol 2016; 75:366-78. [PMID: 26945036 DOI: 10.1093/jnen/nlw008] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
It is estimated that 30%-40% of epilepsy patients are refractory to therapy and animal models are useful for the identification of more efficacious therapeutic agents. Various well-characterized syndrome-specific models are needed to assess their relevance to human seizure disorders and their validity for testing potential therapies. The corneal kindled mouse model of temporal lobe epilepsy (TLE) allows for the rapid screening of investigational compounds, but there is a lack of information as to the specific inflammatory pathology in this model. Similarly, the Theiler murine encephalomyelitis virus (TMEV) model of TLE may prove to be useful for screening, but quantitative assessment of hippocampal pathology is also lacking. We used immunohistochemistry to characterize and quantitate acute neuronal injury and inflammatory features in dorsal CA1 and dentate gyrus regions and in the directly overlying posterior parietal cortex at 2 time points in each of these TLE models. Corneal kindled mice were observed to have astrogliosis, but not microgliosis or neuron cell death. In contrast, TMEV-injected mice had astrogliosis, microgliosis, neuron death, and astrocyte and microglial proliferation. Our results suggest that these 2 animal models might be appropriate for evaluation of distinct therapies for TLE.
Collapse
Affiliation(s)
- Jaycie L Loewen
- From the Interdepartmental Program in Neuroscience (JLL, HSW, KSW); HHMI Med into Grad Program (JLL); Department of Pharmacology and Toxicology (JLL, MLB-H, EJD, HSW, KSW); and Anticonvulsant Drug Development Program (MLB-H, EJD, HSW, KSW), University of Utah, Salt Lake City, Utah, USA
| | - Melissa L Barker-Haliski
- From the Interdepartmental Program in Neuroscience (JLL, HSW, KSW); HHMI Med into Grad Program (JLL); Department of Pharmacology and Toxicology (JLL, MLB-H, EJD, HSW, KSW); and Anticonvulsant Drug Development Program (MLB-H, EJD, HSW, KSW), University of Utah, Salt Lake City, Utah, USA
| | - E Jill Dahle
- From the Interdepartmental Program in Neuroscience (JLL, HSW, KSW); HHMI Med into Grad Program (JLL); Department of Pharmacology and Toxicology (JLL, MLB-H, EJD, HSW, KSW); and Anticonvulsant Drug Development Program (MLB-H, EJD, HSW, KSW), University of Utah, Salt Lake City, Utah, USA
| | - H Steve White
- From the Interdepartmental Program in Neuroscience (JLL, HSW, KSW); HHMI Med into Grad Program (JLL); Department of Pharmacology and Toxicology (JLL, MLB-H, EJD, HSW, KSW); and Anticonvulsant Drug Development Program (MLB-H, EJD, HSW, KSW), University of Utah, Salt Lake City, Utah, USA
| | - Karen S Wilcox
- From the Interdepartmental Program in Neuroscience (JLL, HSW, KSW); HHMI Med into Grad Program (JLL); Department of Pharmacology and Toxicology (JLL, MLB-H, EJD, HSW, KSW); and Anticonvulsant Drug Development Program (MLB-H, EJD, HSW, KSW), University of Utah, Salt Lake City, Utah, USA.
| |
Collapse
|
48
|
Bröer S, Käufer C, Haist V, Li L, Gerhauser I, Anjum M, Bankstahl M, Baumgärtner W, Löscher W. Brain inflammation, neurodegeneration and seizure development following picornavirus infection markedly differ among virus and mouse strains and substrains. Exp Neurol 2016; 279:57-74. [PMID: 26892877 DOI: 10.1016/j.expneurol.2016.02.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/25/2016] [Accepted: 02/13/2016] [Indexed: 01/20/2023]
Abstract
Infections, particularly those caused by viruses, are among the main causes of acquired epilepsy, but the mechanisms causing epileptogenesis are only poorly understood. As a consequence, no treatment exists for preventing epilepsy in patients at risk. Animal models are useful to study epileptogenesis after virus-induced encephalitis and how to interfere with this process, but most viruses that cause encephalitis in rodents are associated with high mortality, so that the processes leading to epilepsy cannot be investigated. Recently, intracerebral infection with Theiler's murine encephalomyelitis virus (TMEV) in C57BL/6 (B6) mice was reported to induce early seizures and epilepsy and it was proposed that the TMEV mouse model represents the first virus infection-driven animal model of epilepsy. In the present study, we characterized this model in two B6 substrains and seizure-resistant SJL/J mice by using three TMEV (sub)strains (BeAn-1, BeAn-2, DA). The idea behind this approach was to study what is and what is not necessary for development of acute and late seizures after brain infection in mice. Receiver operating characteristic (ROC) curve analysis was used to determine which virus-induced brain alterations are associated with seizure development. In B6 mice infected with different TMEV virus (sub)strains, the severity of hippocampal neurodegeneration, amount of MAC3-positive microglia/macrophages, and expression of the interferon-inducible antiviral effector ISG15 were almost perfect at discriminating seizing from non-seizing B6 mice, whereas T-lymphocyte brain infiltration was not found to be a crucial factor. However, intense microglia/macrophage activation and some hippocampal damage were also observed in SJL/J mice. Overall, the TMEV model provides a unique platform to study virus and host factors in ictogenesis and epileptogenesis.
Collapse
Affiliation(s)
- Sonja Bröer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Christopher Käufer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hanover, Germany
| | - Verena Haist
- Department of Pathology, University of Veterinary Medicine, Germany
| | - Lin Li
- Center for Systems Neuroscience, Hanover, Germany; Department of Pathology, University of Veterinary Medicine, Germany
| | - Ingo Gerhauser
- Department of Pathology, University of Veterinary Medicine, Germany
| | - Muneeb Anjum
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hanover, Germany
| | - Marion Bankstahl
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hanover, Germany
| | - Wolfgang Baumgärtner
- Center for Systems Neuroscience, Hanover, Germany; Department of Pathology, University of Veterinary Medicine, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hanover, Germany.
| |
Collapse
|
49
|
Vezzani A, Fujinami RS, White HS, Preux PM, Blümcke I, Sander JW, Löscher W. Infections, inflammation and epilepsy. Acta Neuropathol 2016; 131:211-234. [PMID: 26423537 DOI: 10.1007/s00401-015-1481-5] [Citation(s) in RCA: 301] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 09/18/2015] [Accepted: 09/20/2015] [Indexed: 12/15/2022]
Abstract
Epilepsy is the tendency to have unprovoked epileptic seizures. Anything causing structural or functional derangement of brain physiology may lead to seizures, and different conditions may express themselves solely by recurrent seizures and thus be labelled "epilepsy." Worldwide, epilepsy is the most common serious neurological condition. The range of risk factors for the development of epilepsy varies with age and geographic location. Congenital, developmental and genetic conditions are mostly associated with the development of epilepsy in childhood, adolescence and early adulthood. Head trauma, infections of the central nervous system (CNS) and tumours may occur at any age and may lead to the development of epilepsy. Infections of the CNS are a major risk factor for epilepsy. The reported risk of unprovoked seizures in population-based cohorts of survivors of CNS infections from developed countries is between 6.8 and 8.3 %, and is much higher in resource-poor countries. In this review, the various viral, bacterial, fungal and parasitic infectious diseases of the CNS which result in seizures and epilepsy are discussed. The pathogenesis of epilepsy due to brain infections, as well as the role of experimental models to study mechanisms of epileptogenesis induced by infectious agents, is reviewed. The sterile (non-infectious) inflammatory response that occurs following brain insults is also discussed, as well as its overlap with inflammation due to infections, and the potential role in epileptogenesis. Furthermore, autoimmune encephalitis as a cause of seizures is reviewed. Potential strategies to prevent epilepsy resulting from brain infections and non-infectious inflammation are also considered.
Collapse
Affiliation(s)
- Annamaria Vezzani
- Department of Neuroscience, IRCCS-"Mario Negri" Institute for Pharmacological Research, Milan, Italy
| | - Robert S Fujinami
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - H Steve White
- Department of Pharmacology, University of Utah, Salt Lake City, UT, USA
| | - Pierre-Marie Preux
- INSERM UMR1094, Tropical Neuroepidemiology, Limoges, France
- Institute of Neuroepidemiology and Tropical Neurology, School of Medicine, University of Limoges, Limoges, France
- Center of Epidemiology, Biostatistics, and Research Methodology, CHU Limoges, Limoges, France
| | - Ingmar Blümcke
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Josemir W Sander
- NIHR University College London Hospitals Biomedical Research Centre, UCL Institute of Neurology, London, WC1N £BG, UK
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, 30559, Hannover, Germany.
- Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
50
|
Libbey JE, Doty DJ, Sim JT, Cusick MF, Round JL, Fujinami RS. The effects of diet on the severity of central nervous system disease: One part of lab-to-lab variability. Nutrition 2016; 32:877-83. [PMID: 27133811 DOI: 10.1016/j.nut.2016.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 12/04/2015] [Accepted: 01/10/2016] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Many things can impact the reproducibility of results from laboratory to laboratory. For example, food from various sources can vary markedly in composition. We examined the effects of two different food sources, the Teklad Global Soy Protein-Free Extruded Rodent Diet (irradiated diet) and the Teklad Sterilizable Rodent Diet (autoclaved diet), on central nervous system disease. METHODS Three preclinical models for human disease: Two different experimental autoimmune encephalomyelitis models (multiple sclerosis) and the Theiler's murine encephalomyelitis virus-induced seizure model (epilepsy), were examined for the effects of two different food sources on disease. RESULTS We found that mice fed the irradiated diet had more severe clinical disease and enhanced seizures compared with animals provided the autoclaved diet in both experimental autoimmune encephalomyelitis models examined and in the Theiler's murine encephalomyelitis virus-induced seizure model, respectively. CONCLUSIONS Therefore, just altering the source of food (lab chow) can have marked effects on disease severity and outcome.
Collapse
Affiliation(s)
- Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Daniel J Doty
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Jordan T Sim
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Matthew F Cusick
- Division of Organ Transplantation, Northwestern University, Chicago, IL, USA
| | - June L Round
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA.
| |
Collapse
|