1
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Nimmo J, Byrne R, Daskoulidou N, Watkins L, Carpanini S, Zelek W, Morgan B. The complement system in neurodegenerative diseases. Clin Sci (Lond) 2024; 138:387-412. [PMID: 38505993 PMCID: PMC10958133 DOI: 10.1042/cs20230513] [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: 10/31/2023] [Revised: 02/15/2024] [Accepted: 03/01/2024] [Indexed: 03/21/2024]
Abstract
Complement is an important component of innate immune defence against pathogens and crucial for efficient immune complex disposal. These core protective activities are dependent in large part on properly regulated complement-mediated inflammation. Dysregulated complement activation, often driven by persistence of activating triggers, is a cause of pathological inflammation in numerous diseases, including neurological diseases. Increasingly, this has become apparent not only in well-recognized neuroinflammatory diseases like multiple sclerosis but also in neurodegenerative and neuropsychiatric diseases where inflammation was previously either ignored or dismissed as a secondary event. There is now a large and rapidly growing body of evidence implicating complement in neurological diseases that cannot be comprehensively addressed in a brief review. Here, we will focus on neurodegenerative diseases, including not only the 'classical' neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, but also two other neurological diseases where neurodegeneration is a neglected feature and complement is implicated, namely, schizophrenia, a neurodevelopmental disorder with many mechanistic features of neurodegeneration, and multiple sclerosis, a demyelinating disorder where neurodegeneration is a major cause of progressive decline. We will discuss the evidence implicating complement as a driver of pathology in these diverse diseases and address briefly the potential and pitfalls of anti-complement drug therapy for neurodegenerative diseases.
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Affiliation(s)
- Jacqui Nimmo
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Robert A.J. Byrne
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Nikoleta Daskoulidou
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Lewis M. Watkins
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Sarah M. Carpanini
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Wioleta M. Zelek
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - B. Paul Morgan
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
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2
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Saez-Calveras N, Stuve O. The role of the complement system in Multiple Sclerosis: A review. Front Immunol 2022; 13:970486. [PMID: 36032156 PMCID: PMC9399629 DOI: 10.3389/fimmu.2022.970486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
The complement system has been involved in the pathogenesis of multiple neuroinflammatory and neurodegenerative conditions. In this review, we evaluated the possible role of complement activation in multiple sclerosis (MS) with a focus in progressive MS, where the disease pathogenesis remains to be fully elucidated and treatment options are limited. The evidence for the involvement of the complement system in the white matter plaques and gray matter lesions of MS stems from immunohistochemical analysis of post-mortem MS brains, in vivo serum and cerebrospinal fluid biomarker studies, and animal models of Experimental Autoimmune Encephalomyelitis (EAE). Complement knock-out studies in these animal models have revealed that this system may have a “double-edge sword” effect in MS. On the one hand, complement proteins may aid in promoting the clearance of myelin degradation products and other debris through myeloid cell-mediated phagocytosis. On the other, its aberrant activation may lead to demyelination at the rim of progressive MS white matter lesions as well as synapse loss in the gray matter. The complement system may also interact with known risk factors of MS, including as Epstein Barr Virus (EBV) infection, and perpetuate the activation of CNS self-reactive B cell populations. With the mounting evidence for the involvement of complement in MS, the development of complement modulating therapies for this condition is appealing. Herein, we also reviewed the pharmacological complement inhibitors that have been tested in MS animal models as well as in clinical trials for other neurologic diseases. The potential use of these agents, such as the C5-binding antibody eculizumab in MS will require a detailed understanding of the role of the different complement effectors in this disease and the development of better CNS delivery strategies for these compounds.
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Affiliation(s)
- Nil Saez-Calveras
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Olaf Stuve
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Neurology Section, Veterans Affairs (VA) North Texas Health Care System, Dallas, TX, United States
- *Correspondence: Olaf Stuve,
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3
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Parker SE, Bellingham MC, Woodruff TM. Complement drives circuit modulation in the adult brain. Prog Neurobiol 2022; 214:102282. [DOI: 10.1016/j.pneurobio.2022.102282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 03/24/2022] [Accepted: 05/02/2022] [Indexed: 11/16/2022]
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4
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Paasila PJ, Aramideh JA, Sutherland GT, Graeber MB. Synapses, Microglia, and Lipids in Alzheimer's Disease. Front Neurosci 2022; 15:778822. [PMID: 35095394 PMCID: PMC8789683 DOI: 10.3389/fnins.2021.778822] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 12/06/2021] [Indexed: 12/17/2022] Open
Abstract
Alzheimer's disease (AD) is characterised by synaptic dysfunction accompanied by the microscopically visible accumulation of pathological protein deposits and cellular dystrophy involving both neurons and glia. Late-stage AD shows pronounced loss of synapses and neurons across several differentially affected brain regions. Recent studies of advanced AD using post-mortem brain samples have demonstrated the direct involvement of microglia in synaptic changes. Variants of the Apolipoprotein E and Triggering Receptors Expressed on Myeloid Cells gene represent important determinants of microglial activity but also of lipid metabolism in cells of the central nervous system. Here we review evidence that may help to explain how abnormal lipid metabolism, microglial activation, and synaptic pathophysiology are inter-related in AD.
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Affiliation(s)
- Patrick J. Paasila
- Charles Perkins Centre, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
| | - Jason A. Aramideh
- Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
| | - Greg T. Sutherland
- Charles Perkins Centre, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
| | - Manuel B. Graeber
- Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
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5
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Gruber VE, Luinenburg MJ, Colleselli K, Endmayr V, Anink JJ, Zimmer TS, Jansen F, Gosselaar P, Coras R, Scholl T, Blumcke I, Pimentel J, Hainfellner JA, Höftberger R, Rössler K, Feucht M, van Scheppingen J, Aronica E, Mühlebner A. Increased expression of complement components in tuberous sclerosis complex and focal cortical dysplasia type 2B brain lesions. Epilepsia 2021; 63:364-374. [PMID: 34904712 PMCID: PMC9299842 DOI: 10.1111/epi.17139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 01/07/2023]
Abstract
Objective Increasing evidence supports the contribution of inflammatory mechanisms to the neurological manifestations of epileptogenic developmental pathologies linked to mammalian target of rapamycin (mTOR) pathway dysregulation (mTORopathies), such as tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD). In this study, we aimed to investigate the expression pattern and cellular distribution of the complement factors C1q and C3 in resected cortical tissue of clinically well‐characterized patients with TSC and FCD2B. Methods We applied immunohistochemistry in TSC (n = 29) and FCD2B (n = 32) samples and compared them to autopsy and biopsy controls (n = 27). Furthermore, protein expression was observed via Western blot, and for descriptive colocalization studies immunofluorescence double labeling was performed. Results Protein expression for C3 was significantly upregulated in TSC and FCD2B white and gray matter lesions compared to controls. Staining of the synaptic vesicle protein synaptophysin showed a remarkable increase in the white matter of both TSC and FCD2B. Furthermore, confocal imaging revealed colocalization of complement factors with astroglial, microglial, neuronal, and abnormal cells in various patterns. Significance Our results demonstrate that the prominent activation of the complement pathway represents a common pathological hallmark of TSC and FCD2B, suggesting that complement overactivation may play a role in these mTORopathies.
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Affiliation(s)
| | - Mark J Luinenburg
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Katrin Colleselli
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Verena Endmayr
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Jasper J Anink
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Till S Zimmer
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Floor Jansen
- Department of Child Neurology, Brain Center, University Medical Center Utrecht, Member of the European Reference Network EpiCARE, Utrecht, the Netherlands
| | - Peter Gosselaar
- Department of Neurosurgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Roland Coras
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Theresa Scholl
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Ingmar Blumcke
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - José Pimentel
- Department of Neurology, Santa Maria Hospital, Lisbon, Portugal
| | - Johannes A Hainfellner
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Romana Höftberger
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Karl Rössler
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Martha Feucht
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands.,Epilepsy Institutes of the Netherlands Foundation, Heemstede, the Netherlands
| | - Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands.,Department of Pathology, University Medical Center Utrecht, Utrecht, the Netherlands
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6
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Yarmoska SK, Alawieh AM, Tomlinson S, Hoang KB. Modulation of the Complement System by Neoplastic Disease of the Central Nervous System. Front Immunol 2021; 12:689435. [PMID: 34671342 PMCID: PMC8521155 DOI: 10.3389/fimmu.2021.689435] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 09/10/2021] [Indexed: 12/28/2022] Open
Abstract
The complement system is a highly conserved component of innate immunity that is involved in recognizing and responding to pathogens. The system serves as a bridge between innate and adaptive immunity, and modulation of the complement system can affect the entire host immune response to a foreign insult. Neoplastic diseases have been shown to engage the complement system in order to evade the immune system, gain a selective growth advantage, and co-opt the surrounding environment for tumor proliferation. Historically, the central nervous system has been considered to be an immune-privileged environment, but it is now clear that there are active roles for both innate and adaptive immunity within the central nervous system. Much of the research on the role of immunological modulation of neoplastic disease within the central nervous system has focused on adaptive immunity, even though innate immunity still plays a critical role in the natural history of central nervous system neoplasms. Here, we review the modulation of the complement system by a variety of neoplastic diseases of the central nervous system. We also discuss gaps in the current body of knowledge and comment on future directions for investigation.
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Affiliation(s)
- Steven K. Yarmoska
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, United States
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Ali M. Alawieh
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, United States
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Kimberly B. Hoang
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, United States
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7
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Panitch R, Hu J, Chung J, Zhu C, Meng G, Xia W, Bennett DA, Lunetta KL, Ikezu T, Au R, Stein TD, Farrer LA, Jun GR. Integrative brain transcriptome analysis links complement component 4 and HSPA2 to the APOE ε2 protective effect in Alzheimer disease. Mol Psychiatry 2021; 26:6054-6064. [PMID: 34480088 PMCID: PMC8758485 DOI: 10.1038/s41380-021-01266-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 07/07/2021] [Accepted: 08/12/2021] [Indexed: 02/08/2023]
Abstract
Mechanisms underlying the protective effect of apolipoprotein E (APOE) ε2 against Alzheimer disease (AD) are not well understood. We analyzed gene expression data derived from autopsied brains donated by 982 individuals including 135 APOE ɛ2/ɛ3 carriers. Complement pathway genes C4A and C4B were among the most significantly differentially expressed genes between ɛ2/ɛ3 AD cases and controls. We also identified an APOE ε2/ε3 AD-specific co-expression network enriched for astrocytes, oligodendrocytes and oligodendrocyte progenitor cells containing the genes C4A, C4B, and HSPA2. These genes were significantly associated with the ratio of phosphorylated tau at position 231 to total Tau but not with amyloid-β 42 level, suggesting this APOE ɛ2 related co-expression network may primarily be involved with tau pathology. HSPA2 expression was oligodendrocyte-specific and significantly associated with C4B protein. Our findings provide the first evidence of a crucial role of the complement pathway in the protective effect of APOE ε2 for AD.
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Affiliation(s)
- Rebecca Panitch
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Junming Hu
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Jaeyoon Chung
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Congcong Zhu
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Gaoyuan Meng
- Department of Veterans Affairs Medical Center, Bedford, MA, USA
| | - Weiming Xia
- Department of Veterans Affairs Medical Center, Bedford, MA, USA
- Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Kathryn L Lunetta
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Tsuneya Ikezu
- Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA
- Center for Systems Neuroscience, Boston University School of Medicine, Boston, MA, USA
| | - Rhoda Au
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, USA
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA
| | - Thor D Stein
- Department of Veterans Affairs Medical Center, Bedford, MA, USA
- Department of Pathology & Laboratory Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Lindsay A Farrer
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA.
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA.
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA.
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA.
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USA.
| | - Gyungah R Jun
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA.
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA.
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USA.
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8
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Gregersen E, Betzer C, Kim WS, Kovacs G, Reimer L, Halliday GM, Thiel S, Jensen PH. Alpha-synuclein activates the classical complement pathway and mediates complement-dependent cell toxicity. J Neuroinflammation 2021; 18:177. [PMID: 34399786 PMCID: PMC8369722 DOI: 10.1186/s12974-021-02225-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 07/21/2021] [Indexed: 11/23/2022] Open
Abstract
Background Synucleinopathies are characterized by neurodegeneration and deposition of the presynaptic protein α-synuclein in pathological protein inclusions. Growing evidence suggests the complement system not only has physiological functions in the central nervous system, but also is involved in mediating the pathological loss of synapses in Alzheimer’s disease. However, it is not established whether the complement system has a similar role in the diseases Parkinson's disease, Dementia with Lewy bodies, and multiple system atrophy (MSA) that are associated with α-synuclein aggregate pathology. Methods To investigate if the complement system has a pathological role in synucleinopathies, we assessed the effect of the complement system on the viability of an α-synuclein expressing cell model and examined direct activation of the complement system by α-synuclein in a plate-based activation assay. Finally, we investigated the levels of the initiator of the classical pathway, C1q, in postmortem brain samples from MSA patients. Results We demonstrate that α-synuclein activates the classical complement pathway and mediates complement-dependent toxicity in α-synuclein expressing SH-SY5Y cells. The α-synuclein-dependent cellular toxicity was rescued by the complement inhibitors RaCI (inhibiting C5) and Cp20 (inhibiting C3). Furthermore, we observed a trend for higher levels of C1q in the putamen of MSA subjects than that of controls. Conclusion α-Synuclein can activate the classical complement pathway, and the complement system is involved in α-synuclein-dependent cellular cytotoxicity suggesting the system could play a prodegenerative role in synucleinopathies. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02225-9.
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Affiliation(s)
- Emil Gregersen
- DANDRITE, The Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus C, Denmark.,Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Cristine Betzer
- DANDRITE, The Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus C, Denmark.,Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Woojin S Kim
- Brain and Mind Centre & Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Gergo Kovacs
- DANDRITE, The Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus C, Denmark.,Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Lasse Reimer
- DANDRITE, The Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus C, Denmark.,Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Glenda M Halliday
- Brain and Mind Centre & Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Steffen Thiel
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Poul Henning Jensen
- DANDRITE, The Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus C, Denmark. .,Department of Biomedicine, Aarhus University, Aarhus C, Denmark.
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9
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Lu HJ, Fu YY, Wei QQ, Zhang ZJ. Neuroinflammation in HIV-Related Neuropathic Pain. Front Pharmacol 2021; 12:653852. [PMID: 33959022 PMCID: PMC8093869 DOI: 10.3389/fphar.2021.653852] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 03/31/2021] [Indexed: 12/30/2022] Open
Abstract
In the management of human immunodeficiency virus (HIV) infection around the world, chronic complications are becoming a new problem along with the prolonged life expectancy. Chronic pain is widespread in HIV infected patients and even affects those with a low viral load undergoing long-term treatment with antiviral drugs, negatively influencing the adherence to disease management and quality of life. A large proportion of chronic pain is neuropathic pain, which defined as chronic pain caused by nervous system lesions or diseases, presenting a series of nervous system symptoms including both positive and negative signs. Injury caused by HIV protein, central and peripheral sensitization, and side effects of antiretroviral therapy lead to neuroinflammation, which is regarded as a maladaptive mechanism originally serving to promote regeneration and healing, constituting the main mechanism of HIV-related neuropathic pain. Gp120, as HIV envelope protein, has been found to be the major toxin that induces neuropathic pain. Particularly, the microglia, releasing numerous pro-inflammatory substances (such as TNFα, IL-1β, and IL-6), not only sensitize the neurons but also are the center part of the crosstalk bridging the astrocytes and oligodendrocytes together forming the central sensitization during HIV infection, which is not discussed detailly in recent reviews. In the meantime, some NRTIs and PIs exacerbate the neuroinflammation response. In this review, we highlight the importance of clarifying the mechanism of HIV-related neuropathic pain, and discuss about the limitation of the related studies as future research directions.
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Affiliation(s)
- Huan-Jun Lu
- Institute of Pain Medicine and Special Environmental Medicine, Nantong University, Jiangsu, China
| | - Yuan-Yuan Fu
- Institute of Pain Medicine and Special Environmental Medicine, Nantong University, Jiangsu, China.,Department of Human Anatomy, School of Medicine, Nantong University, Nantong, China
| | - Qian-Qi Wei
- Department of Infectious Diseases, General Hospital of Tibet Military Command, Xizang, China
| | - Zhi-Jun Zhang
- Institute of Pain Medicine and Special Environmental Medicine, Nantong University, Jiangsu, China.,Department of Human Anatomy, School of Medicine, Nantong University, Nantong, China
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10
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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.
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11
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Fatoba O, Itokazu T, Yamashita T. Complement cascade functions during brain development and neurodegeneration. FEBS J 2021; 289:2085-2109. [PMID: 33599083 DOI: 10.1111/febs.15772] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 02/07/2021] [Accepted: 02/16/2021] [Indexed: 12/12/2022]
Abstract
The complement system, an essential tightly regulated innate immune system, is a key regulator of normal central nervous system (CNS) development and function. However, aberrant complement component expression and activation in the brain may culminate into marked neuroinflammatory response, neurodegenerative processes and cognitive impairment. Over the years, complement-mediated neuroinflammatory responses and complement-driven neurodegeneration have been increasingly implicated in the pathogenesis of a wide spectrum of CNS disorders. This review describes how complement system contributes to normal brain development and function. We also discuss how pathologic insults such as misfolded proteins, lipid droplet/lipid droplet-associated protein or glycosaminoglycan accumulation could trigger complement-mediated neuroinflammatory responses and neurodegenerative process in neurodegenerative proteinopathies, age-related macular degeneration and neurodegenerative lysosomal storage disorders.
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Affiliation(s)
- Oluwaseun Fatoba
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, Suita, Japan.,WPI-Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Takahide Itokazu
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, Suita, Japan.,Department of Neuro-Medical Science, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Toshihide Yamashita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, Suita, Japan.,WPI-Immunology Frontier Research Center, Osaka University, Suita, Japan.,Department of Neuro-Medical Science, Graduate School of Medicine, Osaka University, Suita, Japan
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12
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Lo MW, Woodruff TM. Complement: Bridging the innate and adaptive immune systems in sterile inflammation. J Leukoc Biol 2020; 108:339-351. [PMID: 32182389 DOI: 10.1002/jlb.3mir0220-270r] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/07/2020] [Accepted: 02/19/2020] [Indexed: 12/24/2022] Open
Abstract
The complement system is a collection of soluble and membrane-bound proteins that together act as a powerful amplifier of the innate and adaptive immune systems. Although its role in infection is well established, complement is becoming increasingly recognized as a key contributor to sterile inflammation, a chronic inflammatory process often associated with noncommunicable diseases. In this context, damaged tissues release danger signals and trigger complement, which acts on a range of leukocytes to augment and bridge the innate and adaptive immune systems. Given the detrimental effect of chronic inflammation, the complement system is therefore well placed as an anti-inflammatory drug target. In this review, we provide a general outline of the sterile activators, effectors, and targets of the complement system and a series of examples (i.e., hypertension, cancer, allograft transplant rejection, and neuroinflammation) that highlight complement's ability to bridge the 2 arms of the immune system.
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Affiliation(s)
- Martin W Lo
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
| | - Trent M Woodruff
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
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13
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Neuroinflammation and Neurogenesis in Alzheimer's Disease and Potential Therapeutic Approaches. Int J Mol Sci 2020; 21:ijms21030701. [PMID: 31973106 PMCID: PMC7037892 DOI: 10.3390/ijms21030701] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/17/2020] [Accepted: 01/19/2020] [Indexed: 12/17/2022] Open
Abstract
In adult brain, new neurons are generated throughout adulthood in the subventricular zone and the dentate gyrus; this process is commonly known as adult neurogenesis. The regulation or modulation of adult neurogenesis includes various intrinsic pathways (signal transduction pathway and epigenetic or genetic modulation pathways) or extrinsic pathways (metabolic growth factor modulation, vascular, and immune system pathways). Altered neurogenesis has been identified in Alzheimer's disease (AD), in both human AD brains and AD rodent models. The exact mechanism of the dysregulation of adult neurogenesis in AD has not been completely elucidated. However, neuroinflammation has been demonstrated to alter adult neurogenesis. The presence of various inflammatory components, such as immune cells, cytokines, or chemokines, plays a role in regulating the survival, proliferation, and maturation of neural stem cells. Neuroinflammation has also been considered as a hallmark neuropathological feature of AD. In this review, we summarize current, state-of-the art perspectives on adult neurogenesis, neuroinflammation, and the relationship between these two phenomena in AD. Furthermore, we discuss the potential therapeutic approaches, focusing on the anti-inflammatory and proneurogenic interventions that have been reported in this field.
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14
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Cellular and Molecular Mediators of Neuroinflammation in Alzheimer Disease. Int Neurourol J 2019; 23:S54-62. [PMID: 31795604 PMCID: PMC6905206 DOI: 10.5213/inj.1938184.092] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 11/14/2019] [Indexed: 12/26/2022] Open
Abstract
Alzheimer disease (AD) is a neurodegenerative disorder characterized by the loss of neuronal cells and the progressive decline of cognitive function. The major pathological culprit of AD is aggregation of amyloid-β (Aβ) and hyperphosphorylation of tau, eventually leading to progressive neuronal cell death and brain atrophy. However, the detailed molecular and cellular mechanisms underlying AD development as a result of neuronal cell death are little known. Although several hypotheses have been proposed regarding the development of AD, increasingly many studies suggest that the pathological progress of AD is not restricted to neuronal components such as Aβ and tau, but is also closely related to inflammatory responses in the brain. Abnormalities of Aβ and tau cause activity of pattern recognition receptors on the brain’s immune cells, including microglia and astrocytes, and trigger the innate immune system by releasing inflammatory mediators in the pathogenesis of AD. In this review, we present a basic overview of the current knowledge regarding inflammation and molecular mediators in the pathological progress of AD.
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15
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Wang Y, Su Y, Lai W, Huang X, Chu K, Brown J, Hong G. Salidroside Restores an Anti-inflammatory Endothelial Phenotype by Selectively Inhibiting Endothelial Complement After Oxidative Stress. Inflammation 2019; 43:310-325. [DOI: 10.1007/s10753-019-01121-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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16
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Ma Y, Liu Y, Zhang Z, Yang GY. Significance of Complement System in Ischemic Stroke: A Comprehensive Review. Aging Dis 2019; 10:429-462. [PMID: 31011487 PMCID: PMC6457046 DOI: 10.14336/ad.2019.0119] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/19/2019] [Indexed: 12/14/2022] Open
Abstract
The complement system is an essential part of innate immunity, typically conferring protection via eliminating pathogens and accumulating debris. However, the defensive function of the complement system can exacerbate immune, inflammatory, and degenerative responses in various pathological conditions. Cumulative evidence indicates that the complement system plays a critical role in the pathogenesis of ischemic brain injury, as the depletion of certain complement components or the inhibition of complement activation could reduce ischemic brain injury. Although multiple candidates modulating or inhibiting complement activation show massive potential for the treatment of ischemic stroke, the clinical availability of complement inhibitors remains limited. The complement system is also involved in neural plasticity and neurogenesis during cerebral ischemia. Thus, unexpected side effects could be induced if the systemic complement system is inhibited. In this review, we highlighted the recent concepts and discoveries of the roles of different kinds of complement components, such as C3a, C5a, and their receptors, in both normal brain physiology and the pathophysiology of brain ischemia. In addition, we comprehensively reviewed the current development of complement-targeted therapy for ischemic stroke and discussed the challenges of bringing these therapies into the clinic. The design of future experiments was also discussed to better characterize the role of complement in both tissue injury and recovery after cerebral ischemia. More studies are needed to elucidate the molecular and cellular mechanisms of how complement components exert their functions in different stages of ischemic stroke to optimize the intervention of targeting the complement system.
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Affiliation(s)
- Yuanyuan Ma
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Yanqun Liu
- 3Department of Neurology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Zhijun Zhang
- 2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Guo-Yuan Yang
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
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17
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Carpanini SM, Torvell M, Morgan BP. Therapeutic Inhibition of the Complement System in Diseases of the Central Nervous System. Front Immunol 2019; 10:362. [PMID: 30886620 PMCID: PMC6409326 DOI: 10.3389/fimmu.2019.00362] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/12/2019] [Indexed: 12/14/2022] Open
Abstract
The complement system plays critical roles in development, homeostasis, and regeneration in the central nervous system (CNS) throughout life; however, complement dysregulation in the CNS can lead to damage and disease. Complement proteins, regulators, and receptors are widely expressed throughout the CNS and, in many cases, are upregulated in disease. Genetic and epidemiological studies, cerebrospinal fluid (CSF) and plasma biomarker measurements and pathological analysis of post-mortem tissues have all implicated complement in multiple CNS diseases including multiple sclerosis (MS), neuromyelitis optica (NMO), neurotrauma, stroke, amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). Given this body of evidence implicating complement in diverse brain diseases, manipulating complement in the brain is an attractive prospect; however, the blood-brain barrier (BBB), critical to protect the brain from potentially harmful agents in the circulation, is also impermeable to current complement-targeting therapeutics, making drug design much more challenging. For example, antibody therapeutics administered systemically are essentially excluded from the brain. Recent protocols have utilized "Trojan horse" techniques to transport therapeutics across the BBB or used osmotic shock or ultrasound to temporarily disrupt the BBB. Most research to date exploring the impact of complement inhibition on CNS diseases has been in animal models, and some of these studies have generated convincing data; for example, in models of MS, NMO, and stroke. There have been a few recent clinical trials of available anti-complement drugs in CNS diseases associated with BBB impairment, for example the use of the anti-C5 monoclonal antibody (mAb) eculizumab in NMO, but for most CNS diseases there have been no human trials of anti-complement therapies. Here we will review the evidence implicating complement in diverse CNS disorders, from acute, such as traumatic brain or spine injury, to chronic, including demyelinating, neuroinflammatory, and neurodegenerative diseases. We will discuss the particular problems of drug access into the CNS and explore ways in which anti-complement therapies might be tailored for CNS disease.
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Affiliation(s)
- Sarah M Carpanini
- UK Dementia Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Megan Torvell
- UK Dementia Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Bryan Paul Morgan
- UK Dementia Research Institute, Cardiff University, Cardiff, United Kingdom.,Division of Infection and Immunity, School of Medicine, Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
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18
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Druart M, Le Magueresse C. Emerging Roles of Complement in Psychiatric Disorders. Front Psychiatry 2019; 10:573. [PMID: 31496960 PMCID: PMC6712161 DOI: 10.3389/fpsyt.2019.00573] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 07/22/2019] [Indexed: 12/12/2022] Open
Abstract
The complement system consists of more than 30 proteins that have long been known to participate to the immune defence against pathogens and to the removal of damaged cells. Their role, however, extends beyond immunity and clearance of altered "self" components in the periphery. In particular, complement proteins can be induced by all cell types in the brain. Recent discoveries highlight the role of complement in normal and pathological brain development. Specifically, the complement system mediates synaptic pruning, a developmental process whereby supernumerary synapses are eliminated in the immature brain. The complement system has been implicated in pathological synapse elimination in schizophrenia, West Nile virus infection, and lupus, all of which are associated with psychiatric manifestations. Complement also contributes to synapse loss in neurodegenerative conditions. This review provides a brief overview of the well-studied role of complement molecules in immunity. The contribution of complement to embryonic and adult neurogenesis, neuronal migration, and developmental synaptic elimination in the normal brain is reviewed. We discuss the role of complement in synapse loss in psychiatric and neurological diseases and evaluate the therapeutic potential of complement-targeting drugs for brain disorders.
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Affiliation(s)
- Mélanie Druart
- INSERM UMR-S 1270, Paris, France.,Science and Engineering Faculty, Sorbonne Université, Paris, France.,Institut du Fer à Moulin, Paris, France
| | - Corentin Le Magueresse
- INSERM UMR-S 1270, Paris, France.,Science and Engineering Faculty, Sorbonne Université, Paris, France.,Institut du Fer à Moulin, Paris, France
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19
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Chiou B, Lucassen E, Sather M, Kallianpur A, Connor J. Semaphorin4A and H-ferritin utilize Tim-1 on human oligodendrocytes: A novel neuro-immune axis. Glia 2018; 66:1317-1330. [PMID: 29457657 DOI: 10.1002/glia.23313] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/05/2018] [Accepted: 02/05/2018] [Indexed: 01/02/2023]
Abstract
Deficiency of trophic factors relating to the survival of oligodendrocytes, combined with direct interactions with the immune system, are favored paradigms that are increasingly implicated in demyelinating diseases of the central nervous system. We and others have previously shown that Sema4A and H-ferritin interact through the T-cell immunoglobulin and mucin domain (Tim-2) receptor in mice. H-ferritin has been identified as the iron delivery protein for oligodendrocytes, whereas Sema4A causes a direct cytotoxic effect. However, the expression of Tim-2 has not been detected in humans. Here, we demonstrate that, similar to rodents, human oligodendrocytes undergo apoptosis when exposed to Sema4A and take up H-ferritin for meeting iron requirements and that these functions are mediated via the Tim-1 receptor. Moreover, we also demonstrate the ability of H-ferritin to block Sema4A-mediated cytotoxicity. Furthermore, we show in a series of pilot studies that Sema4A is detectable in the CSF of multiple sclerosis patients and HIV-seropositive persons and can induce oligodendrocyte cell death. Together, these results identify a novel iron uptake mechanism for human oligodendrocytes and a connection between oligodendrocytes and the immune system.
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Affiliation(s)
- Brian Chiou
- Department of Neurosurgery, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Elisabeth Lucassen
- Department of Neurology, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Michael Sather
- Department of Neurosurgery, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Asha Kallianpur
- Department of Genomic Medicine, Cleveland Clinic/Lerner Research Institute, Cleveland, Ohio.,Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - James Connor
- Department of Neurosurgery, Penn State University College of Medicine, Hershey, Pennsylvania
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20
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Protective Humoral Immunity in the Central Nervous System Requires Peripheral CD19-Dependent Germinal Center Formation following Coronavirus Encephalomyelitis. J Virol 2017; 91:JVI.01352-17. [PMID: 28931676 DOI: 10.1128/jvi.01352-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/13/2017] [Indexed: 02/06/2023] Open
Abstract
B cell subsets with phenotypes characteristic of naive, non-isotype-switched, memory (Bmem) cells and antibody-secreting cells (ASC) accumulate in various models of central nervous system (CNS) inflammation, including viral encephalomyelitis. During neurotropic coronavirus JHMV infection, infiltration of protective ASC occurs after T cell-mediated viral control and is preceded by accumulation of non-isotype-switched IgD+ and IgM+ B cells. However, the contribution of peripheral activation events in cervical lymph nodes (CLN) to driving humoral immune responses in the infected CNS is poorly defined. CD19, a signaling component of the B cell receptor complex, is one of multiple regulators driving B cell differentiation and germinal center (GC) formation by lowering the threshold of antigen-driven activation. JHMV-infected CD19-/- mice were thus used to determine how CD19 affects CNS recruitment of B cell subsets. Early polyclonal ASC expansion, GC formation, and virus-specific ASC were all significantly impaired in CLN of CD19-/- mice compared to wild-type (WT) mice, consistent with lower and unsustained virus-specific serum antibody (Ab). ASC were also significantly reduced in the CNS, resulting in increased infectious virus during persistence. Nevertheless, CD19 deficiency did not affect early CNS IgD+ B cell accumulation. The results support the notion that CD19-independent factors drive early B cell mobilization and recruitment to the infected CNS, while delayed accumulation of virus-specific, isotype-switched ASC requires CD19-dependent GC formation in CLN. CD19 is thus essential for both sustained serum Ab and protective local Ab within the CNS following JHMV encephalomyelitis.IMPORTANCE CD19 activation is known to promote GC formation and to sustain serum Ab responses following antigen immunization and viral infections. However, the contribution of CD19 in the context of CNS infections has not been evaluated. This study demonstrates that antiviral protective ASC in the CNS are dependent on CD19 activation and peripheral GC formation, while accumulation of early-recruited IgD+ B cells is CD19 independent. This indicates that IgD+ B cells commonly found early in the CNS do not give rise to local ASC differentiation and that only antigen-primed, peripheral GC-derived ASC infiltrate the CNS, thereby limiting potentially harmful nonspecific Ab secretion. Expanding our understanding of activation signals driving CNS migration of distinct B cell subsets during neuroinflammatory insults is critical for preventing and managing acute encephalitic infections, as well as preempting reactivation of persistent viruses during immune-suppressive therapies targeting B cells in multiple sclerosis (MS), such as rituximab and ocrelizumab.
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21
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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.
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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
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22
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Dá Mesquita S, Ferreira AC, Sousa JC, Correia-Neves M, Sousa N, Marques F. Insights on the pathophysiology of Alzheimer's disease: The crosstalk between amyloid pathology, neuroinflammation and the peripheral immune system. Neurosci Biobehav Rev 2016; 68:547-562. [PMID: 27328788 DOI: 10.1016/j.neubiorev.2016.06.014] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 06/09/2016] [Accepted: 06/14/2016] [Indexed: 12/19/2022]
Abstract
Alzheimer's disease (AD) is the most common form of dementia, whose prevalence is growing along with the increased life expectancy. Although the accumulation and deposition of amyloid beta (Aβ) peptides in the brain is viewed as one of the pathological hallmarks of AD and underlies, at least in part, brain cell dysfunction and behavior alterations, the etiology of this neurodegenerative disease is still poorly understood. Noticeably, increased amyloid load is accompanied by marked inflammatory alterations, both at the level of the brain parenchyma and at the barriers of the brain. However, it is debatable whether the neuroinflammation observed in aging and in AD, together with alterations in the peripheral immune system, are responsible for increased amyloidogenesis, decreased clearance of Aβ out of the brain and/or the marked deficits in memory and cognition manifested by AD patients. Herein, we scrutinize some important traits of the pathophysiology of aging and AD, focusing on the interplay between the amyloidogenic pathway, neuroinflammation and the peripheral immune system.
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Affiliation(s)
- Sandro Dá Mesquita
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga, Guimaraes, Portugal
| | - Ana Catarina Ferreira
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga, Guimaraes, Portugal
| | - João Carlos Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga, Guimaraes, Portugal
| | - Margarida Correia-Neves
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga, Guimaraes, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga, Guimaraes, Portugal
| | - Fernanda Marques
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga, Guimaraes, Portugal.
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23
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Hawrylycz M, Miller JA, Menon V, Feng D, Dolbeare T, Guillozet-Bongaarts AL, Jegga AG, Aronow BJ, Lee CK, Bernard A, Glasser MF, Dierker DL, Menche J, Szafer A, Collman F, Grange P, Berman KA, Mihalas S, Yao Z, Stewart L, Barabási AL, Schulkin J, Phillips J, Ng L, Dang C, Haynor DR, Jones A, Van Essen DC, Koch C, Lein E. Canonical genetic signatures of the adult human brain. Nat Neurosci 2015; 18:1832-44. [PMID: 26571460 PMCID: PMC4700510 DOI: 10.1038/nn.4171] [Citation(s) in RCA: 367] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Accepted: 10/16/2015] [Indexed: 11/09/2022]
Abstract
The structure and function of the human brain are highly stereotyped, implying a conserved molecular program responsible for its development, cellular structure and function. We applied a correlation-based metric called differential stability to assess reproducibility of gene expression patterning across 132 structures in six individual brains, revealing mesoscale genetic organization. The genes with the highest differential stability are highly biologically relevant, with enrichment for brain-related annotations, disease associations, drug targets and literature citations. Using genes with high differential stability, we identified 32 anatomically diverse and reproducible gene expression signatures, which represent distinct cell types, intracellular components and/or associations with neurodevelopmental and neurodegenerative disorders. Genes in neuron-associated compared to non-neuronal networks showed higher preservation between human and mouse; however, many diversely patterned genes displayed marked shifts in regulation between species. Finally, highly consistent transcriptional architecture in neocortex is correlated with resting state functional connectivity, suggesting a link between conserved gene expression and functionally relevant circuitry.
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Affiliation(s)
| | - Jeremy A Miller
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Vilas Menon
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - David Feng
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Tim Dolbeare
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | | | - Anil G Jegga
- Division of Biomedical Informatics, Cincinnati Children's Hospital and Medical Center, Cincinnati, Ohio, USA
| | - Bruce J Aronow
- Division of Biomedical Informatics, Cincinnati Children's Hospital and Medical Center, Cincinnati, Ohio, USA
| | - Chang-Kyu Lee
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Amy Bernard
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Matthew F Glasser
- Department of Anatomy and Neurobiology, Washington University, St. Louis, Missouri, USA
| | - Donna L Dierker
- Department of Anatomy and Neurobiology, Washington University, St. Louis, Missouri, USA
| | - Jörg Menche
- Center for Complex Networks Research, Northeastern University, Boston, Massachusetts, USA.,Department of Physics, Northeastern University, Boston, Massachusetts, USA.,Center for Network Science, Central European University, Budapest, Hungary
| | - Aaron Szafer
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Forrest Collman
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Pascal Grange
- Department of Mathematical Sciences, Xi'an Jiaotong-Liverpool University, Jiangsu, China
| | - Kenneth A Berman
- Department of Electrical Engineering and Computing Systems, University of Cincinnati, Cincinnati, Ohio, USA
| | - Stefan Mihalas
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Zizhen Yao
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Lance Stewart
- Institute for Protein Design, University of Washington, Seattle, Washington, USA
| | - Albert-László Barabási
- Center for Complex Networks Research, Northeastern University, Boston, Massachusetts, USA.,Department of Physics, Northeastern University, Boston, Massachusetts, USA.,Center for Network Science, Central European University, Budapest, Hungary.,Center for Cancer Systems Biology and Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jay Schulkin
- Department of Neuroscience, Georgetown University, Washington, DC, USA
| | - John Phillips
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Lydia Ng
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Chinh Dang
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - David R Haynor
- Department of Radiology, The University of Washington, Seattle, Washington, USA
| | - Allan Jones
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - David C Van Essen
- Department of Anatomy and Neurobiology, Washington University, St. Louis, Missouri, USA
| | - Christof Koch
- The Allen Institute for Brain Science, Seattle, Washington, USA
| | - Ed Lein
- The Allen Institute for Brain Science, Seattle, Washington, USA
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24
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Zeis T, Enz L, Schaeren-Wiemers N. The immunomodulatory oligodendrocyte. Brain Res 2015; 1641:139-148. [PMID: 26423932 DOI: 10.1016/j.brainres.2015.09.021] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 09/17/2015] [Accepted: 09/20/2015] [Indexed: 01/12/2023]
Abstract
Oligodendrocytes, the myelinating glial cells of the central nervous system (CNS), are due to their high specialization and metabolic needs highly vulnerable to various insults. This led to a general view that oligodendrocytes are defenseless victims during brain damage such as occurs in acute and chronic CNS inflammation. However, this view is challenged by increasing evidence that oligodendrocytes are capable of expressing a wide range of immunomodulatory molecules. They express various cytokines and chemokines (e.g. Il-1β, Il17A, CCL2, CXCL10), antigen presenting molecules (MHC class I and II) and co-stimulatory molecules (e.g. CD9, CD81), complement and complement receptor molecules (e.g. C1s, C2 and C3, C1R), complement regulatory molecules (e.g. CD46, CD55, CD59), tetraspanins (e.g. TSPAN2), neuroimmune regulatory proteins (e.g. CD200, CD47) as well as extracellular matrix proteins (e.g. VCAN) and many others. Their potential immunomodulatory properties can, at specific times and locations, influence ongoing immune processes as shown by numerous publications. Therefore, oligodendrocytes are well capable of immunomodulation, especially during the initiation or resolution of immune processes in which subtle signaling might tip the scale. A better understanding of the immunomodulatory oligodendrocyte can help to invent new, innovative therapeutic interventions in various diseases such as Multiple Sclerosis. This article is part of a Special Issue entitled SI: Myelin Evolution.
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Affiliation(s)
- Thomas Zeis
- Neurobiology, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Lukas Enz
- Neurobiology, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Nicole Schaeren-Wiemers
- Neurobiology, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland.
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25
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Benito E, Urbanke H, Ramachandran B, Barth J, Halder R, Awasthi A, Jain G, Capece V, Burkhardt S, Navarro-Sala M, Nagarajan S, Schütz AL, Johnsen SA, Bonn S, Lührmann R, Dean C, Fischer A. HDAC inhibitor-dependent transcriptome and memory reinstatement in cognitive decline models. J Clin Invest 2015; 125:3572-84. [PMID: 26280576 DOI: 10.1172/jci79942] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 07/08/2015] [Indexed: 12/19/2022] Open
Abstract
Aging and increased amyloid burden are major risk factors for cognitive diseases such as Alzheimer's disease (AD). Effective therapies for these diseases are lacking. Here, we evaluated mouse models of age-associated memory impairment and amyloid deposition to study transcriptome and cell type-specific epigenome plasticity in the brain and peripheral organs. We determined that aging and amyloid pathology are associated with inflammation and impaired synaptic function in the hippocampal CA1 region as the result of epigenetic-dependent alterations in gene expression. In both amyloid and aging models, inflammation was associated with increased gene expression linked to a subset of transcription factors, while plasticity gene deregulation was differentially mediated. Amyloid pathology impaired histone acetylation and decreased expression of plasticity genes, while aging altered H4K12 acetylation-linked differential splicing at the intron-exon junction in neurons, but not nonneuronal cells. Furthermore, oral administration of the clinically approved histone deacetylase inhibitor vorinostat not only restored spatial memory, but also exerted antiinflammatory action and reinstated epigenetic balance and transcriptional homeostasis at the level of gene expression and exon usage. This study provides a systems-level investigation of transcriptome plasticity in the hippocampal CA1 region in aging and AD models and suggests that histone deacetylase inhibitors should be further explored as a cost-effective therapeutic strategy against age-associated cognitive decline.
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26
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Bai X, Wang Y, Man L, Zhang Q, Sun C, Hu W, Liu Y, Liu M, Gu X, Wang Y. CD59 mediates cartilage patterning during spontaneous tail regeneration. Sci Rep 2015; 5:12798. [PMID: 26238652 PMCID: PMC4523838 DOI: 10.1038/srep12798] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 07/10/2015] [Indexed: 12/17/2022] Open
Abstract
The regeneration-competent adult animals have ability to regenerate their lost complex appendages with a near-perfect replica, owing to the positional identity acquired by the progenitor cells in the blastema, i.e. the blastemal cells. CD59, a CD59/Ly6 family member, has been identified as a regulator of positional identity in the tail blastemal cells of Gekko japonicus. To determine whether this function of CD59 is unique to the regenerative amniote(s) and how CD59 mediates PD axis patterning during tail regeneration, we examined its protective role on the complement-mediated cell lysis and intervened CD59 expression in the tail blastemal cells using an in vivo model of adenovirus transfection. Our data revealed that gecko CD59 was able to inhibit complement-mediated cell lysis. Meanwhile, CD59 functioned on positional identity through expression in cartilage precursor cells. Intervening positional identity by overexpression or siRNA knockdown of CD59 resulted in abnormal cartilaginous cone patterning due to the decreased differentiation of blastemal cells to cartilage precursor cells. The cartilage formation-related genes were found to be under the regulation of CD59. These results indicate that CD59, an evolutionarily transitional molecule linking immune and regenerative regulation, affects tail regeneration by mediating cartilage patterning.
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Affiliation(s)
- Xue Bai
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Yingjie Wang
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Lili Man
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Qing Zhang
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Cheng Sun
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Wen Hu
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Yan Liu
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Mei Liu
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Xiaosong Gu
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
| | - Yongjun Wang
- Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, PR China
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Abstract
The past two decades of research into the pathogenesis of Alzheimer disease (AD) have been driven largely by the amyloid hypothesis; the neuroinflammation that is associated with AD has been assumed to be merely a response to pathophysiological events. However, new data from preclinical and clinical studies have established that immune system-mediated actions in fact contribute to and drive AD pathogenesis. These insights have suggested both novel and well-defined potential therapeutic targets for AD, including microglia and several cytokines. In addition, as inflammation in AD primarily concerns the innate immune system - unlike in 'typical' neuroinflammatory diseases such as multiple sclerosis and encephalitides - the concept of neuroinflammation in AD may need refinement.
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Karch CM, Goate AM. Alzheimer's disease risk genes and mechanisms of disease pathogenesis. Biol Psychiatry 2015; 77:43-51. [PMID: 24951455 PMCID: PMC4234692 DOI: 10.1016/j.biopsych.2014.05.006] [Citation(s) in RCA: 855] [Impact Index Per Article: 95.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 04/30/2014] [Accepted: 05/05/2014] [Indexed: 01/18/2023]
Abstract
We review the genetic risk factors for late-onset Alzheimer's disease (AD) and their role in AD pathogenesis. More recent advances in understanding of the human genome-technologic advances in methods to analyze millions of polymorphisms in thousands of subjects-have revealed new genes associated with AD risk, including ABCA7, BIN1, CASS4, CD33, CD2AP, CELF1, CLU, CR1, DSG2, EPHA1, FERMT2, HLA-DRB5-DBR1, INPP5D, MS4A, MEF2C, NME8, PICALM, PTK2B, SLC24H4-RIN3, SORL1, and ZCWPW1. Emerging technologies to analyze the entire genome in large data sets have also revealed coding variants that increase AD risk: PLD3 and TREM2. We review the relationship between these AD risk genes and the cellular and neuropathologic features of AD. Understanding the mechanisms underlying the association of these genes with risk for disease will provide the most meaningful targets for therapeutic development to date.
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Affiliation(s)
| | - Alison M. Goate
- Corresponding author Contact information: Department of Psychiatry, Washington University School of Medicine, 425 S. Euclid Ave, Campus Box 8134, St. Louis, MO 63110, phone: 314-362-8691, fax: 314-747-2983,
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29
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Stilling RM, Benito E, Gertig M, Barth J, Capece V, Burkhardt S, Bonn S, Fischer A. De-regulation of gene expression and alternative splicing affects distinct cellular pathways in the aging hippocampus. Front Cell Neurosci 2014; 8:373. [PMID: 25431548 PMCID: PMC4230043 DOI: 10.3389/fncel.2014.00373] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 10/21/2014] [Indexed: 01/20/2023] Open
Abstract
Aging is accompanied by gradually increasing impairment of cognitive abilities and constitutes the main risk factor of neurodegenerative conditions like Alzheimer's disease (AD). The underlying mechanisms are however not well understood. Here we analyze the hippocampal transcriptome of young adult mice and two groups of mice at advanced age using RNA sequencing. This approach enabled us to test differential expression of coding and non-coding transcripts, as well as differential splicing and RNA editing. We report a specific age-associated gene expression signature that is associated with major genetic risk factors for late-onset AD (LOAD). This signature is dominated by neuroinflammatory processes, specifically activation of the complement system at the level of increased gene expression, while de-regulation of neuronal plasticity appears to be mediated by compromised RNA splicing.
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Affiliation(s)
- Roman M Stilling
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen Göttingen, Germany ; Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
| | - Eva Benito
- Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
| | - Michael Gertig
- Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
| | - Jonas Barth
- Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
| | - Vincenzo Capece
- Research Group for Computational Analysis of Biological Networks, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
| | - Susanne Burkhardt
- Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
| | - Stefan Bonn
- Research Group for Computational Analysis of Biological Networks, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
| | - Andre Fischer
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen Göttingen, Germany ; Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen Göttingen, Germany
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30
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Peterson SL, Anderson AJ. Complement and spinal cord injury: traditional and non-traditional aspects of complement cascade function in the injured spinal cord microenvironment. Exp Neurol 2014; 258:35-47. [PMID: 25017886 DOI: 10.1016/j.expneurol.2014.04.028] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 04/14/2014] [Accepted: 04/28/2014] [Indexed: 12/21/2022]
Abstract
The pathology associated with spinal cord injury (SCI) is caused not only by primary mechanical trauma, but also by secondary responses of the injured CNS. The inflammatory response to SCI is robust and plays an important but complex role in the progression of many secondary injury-associated pathways. Although recent studies have begun to dissect the beneficial and detrimental roles for inflammatory cells and proteins after SCI, many of these neuroimmune interactions are debated, not well understood, or completely unexplored. In this regard, the complement cascade is a key component of the inflammatory response to SCI, but is largely underappreciated, and our understanding of its diverse interactions and effects in this pathological environment is limited. In this review, we discuss complement in the context of SCI, first in relation to traditional functions for complement cascade activation, and then in relation to novel roles for complement proteins in a variety of models.
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Affiliation(s)
- Sheri L Peterson
- Sue & Bill Gross Stem Cell Center, University of California, Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697, USA; Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA
| | - Aileen J Anderson
- Sue & Bill Gross Stem Cell Center, University of California, Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697, USA; Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, CA 92697, USA; Department of Physical Medicine and Rehabilitation, University of California, Irvine, Irvine, CA 92697, USA.
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31
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Peferoen L, Kipp M, van der Valk P, van Noort JM, Amor S. Oligodendrocyte-microglia cross-talk in the central nervous system. Immunology 2014; 141:302-13. [PMID: 23981039 DOI: 10.1111/imm.12163] [Citation(s) in RCA: 274] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 08/21/2013] [Accepted: 08/21/2013] [Indexed: 12/13/2022] Open
Abstract
Communication between the immune system and the central nervous system (CNS) is exemplified by cross-talk between glia and neurons shown to be essential for maintaining homeostasis. While microglia are actively modulated by neurons in the healthy brain, little is known about the cross-talk between oligodendrocytes and microglia. Oligodendrocytes, the myelin-forming cells in the CNS, are essential for the propagation of action potentials along axons, and additionally serve to support neurons by producing neurotrophic factors. In demyelinating diseases such as multiple sclerosis, oligodendrocytes are thought to be the victims. Here, we review evidence that oligodendrocytes also have strong immune functions, express a wide variety of innate immune receptors, and produce and respond to chemokines and cytokines that modulate immune responses in the CNS. We also review evidence that during stress events in the brain, oligodendrocytes can trigger a cascade of protective and regenerative responses, in addition to responses that elicit progressive neurodegeneration. Knowledge of the cross-talk between microglia and oligodendrocytes may continue to uncover novel pathways of immune regulation in the brain that could be further exploited to control neuroinflammation and degeneration.
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Affiliation(s)
- Laura Peferoen
- Pathology Department, VU University Medical Centre, Amsterdam, the Netherlands
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32
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Malekzadeh A, Teunissen C. Recent progress in omics-driven analysis of MS to unravel pathological mechanisms. Expert Rev Neurother 2014; 13:1001-16. [PMID: 24053344 DOI: 10.1586/14737175.2013.835602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
At present, the pathophysiology and specific biological markers reflecting pathology of multiple sclerosis (MS) remain undetermined. The risk of developing MS is considered to depend on genetic susceptibility and environmental factors. The interaction of environmental factors with epigenetic mechanisms could affect the transcriptional level and therefore also the translational level. In the last decade, growing amount of hypothesis-free 'omics' studies have shed light on the potential MS mechanisms and raised potential biomarker targets. To understand MS pathophysiology and discover a subset of biomarkers, it is becoming essential to take a step forward and integrate the findings of the different fields of 'omics' into a systems biology network. In this review, we will discuss the recent findings of the genomic, transcriptomic and proteomic fields for MS and aim to make a unifying model.
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Affiliation(s)
- Arjan Malekzadeh
- Department of Clinical Chemistry, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
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33
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Owens T, Khorooshi R, Wlodarczyk A, Asgari N. Interferons in the central nervous system: A few instruments play many tunes. Glia 2013; 62:339-55. [DOI: 10.1002/glia.22608] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Trevor Owens
- Department of Neurobiology Research, Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - Reza Khorooshi
- Department of Neurobiology Research, Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - Agnieszka Wlodarczyk
- Department of Neurobiology Research, Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - Nasrin Asgari
- Department of Neurobiology Research, Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
- Department of Neurology; Vejle Hospital; Denmark
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34
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Wyss-Coray T, Rogers J. Inflammation in Alzheimer disease-a brief review of the basic science and clinical literature. Cold Spring Harb Perspect Med 2013; 2:a006346. [PMID: 22315714 DOI: 10.1101/cshperspect.a006346] [Citation(s) in RCA: 663] [Impact Index Per Article: 60.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Biochemical and neuropathological studies of brains from individuals with Alzheimer disease (AD) provide clear evidence for an activation of inflammatory pathways, and long-term use of anti-inflammatory drugs is linked with reduced risk to develop the disease. As cause and effect relationships between inflammation and AD are being worked out, there is a realization that some components of this complex molecular and cellular machinery are most likely promoting pathological processes leading to AD, whereas other components serve to do the opposite. The challenge will be to find ways of fine tuning inflammation to delay, prevent, or treat AD.
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Affiliation(s)
- Tony Wyss-Coray
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California 94305-5235, USA; Geriatric Research Education and Clinical Center, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304, USA
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35
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Abstract
Multiorgan failure (MOF) represents the leading cause of death in patients with sepsis and systemic inflammatory response syndrome (SIRS) following severe trauma. The underlying immune response is highly complex and involves activation of the complement system as a crucial entity of innate immunity. Uncontrolled activation of the complement system during sepsis and SIRS with in excessive generation of complement activation products contributes to an ensuing dysfunction of various organ systems. In the present review, mechanisms of the inflammatory response in the development of MOF in sepsis and SIRS with particular focus on the complement system are discussed.
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36
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Microglia, Alzheimer's disease, and complement. Int J Alzheimers Dis 2012; 2012:983640. [PMID: 22957298 PMCID: PMC3432348 DOI: 10.1155/2012/983640] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 05/01/2012] [Accepted: 05/07/2012] [Indexed: 02/02/2023] Open
Abstract
Microglia, the immune cell of the brain, are implicated in cascades leading to neuronal loss and cognitive decline in Alzheimer's disease (AD). Recent genome-wide association studies have indicated a number of risk factors for the development of late-onset AD. Two of these risk factors are an altered immune response and polymorphisms in complement receptor 1. In view of these findings, we discuss how complement signalling in the AD brain and microglial responses in AD intersect. Dysregulation of the complement cascade, either by changes in receptor expression, enhanced activation of different complement pathways or imbalances between complement factor production and complement cascade inhibitors may all contribute to the involvement of complement in AD. Altered complement signalling may reduce the ability of microglia to phagocytose apoptotic cells and clear amyloid beta peptides, modulate the expression by microglia of complement components and receptors, promote complement factor production by plaque-associated cytokines derived from activated microglia and astrocytes, and disrupt complement inhibitor production. The evidence presented here indicates that microglia in AD are influenced by complement factors to adopt protective or harmful phenotypes and the challenge ahead lies in understanding how this can be manipulated to therapeutic advantage to treat late onset AD.
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37
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Libbey JE, Fujinami RS. Neurotropic viral infections leading to epilepsy: focus on Theiler's murine encephalomyelitis virus. Future Virol 2011; 6:1339-1350. [PMID: 22267964 PMCID: PMC3259611 DOI: 10.2217/fvl.11.107] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neurotropic viruses cause viral encephalitis and are associated with the development of seizures/epilepsy. The first infection-driven animal model for epilepsy, the Theiler's murine encephalomyelitis virus-induced seizure model is described herein. Intracerebral infection of C57BL/6 mice with Theiler's murine encephalomyelitis virus induces acute seizures from which the animals recover. However, once the virus is cleared, a significant portion of the animals that experienced acute seizures later develop epilepsy. Components of the innate immune response to viral infection, including IL-6 and complement component 3, have been implicated in the development of acute seizures. Multiple mechanisms, including neuronal cell destruction and cytokine activation, play a role in the development of acute seizures. Future studies targeting the innate immune response will lead to new therapies for seizures/epilepsy.
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Affiliation(s)
- Jane E Libbey
- Department of Pathology, University of Utah, 30 North 1900 East, 3R330 SOM, Salt Lake City, UT 84132, USA
| | - Robert S Fujinami
- Department of Pathology, University of Utah, 30 North 1900 East, 3R330 SOM, Salt Lake City, UT 84132, USA
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38
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Crehan H, Holton P, Wray S, Pocock J, Guerreiro R, Hardy J. Complement receptor 1 (CR1) and Alzheimer's disease. Immunobiology 2011; 217:244-50. [PMID: 21840620 DOI: 10.1016/j.imbio.2011.07.017] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 06/22/2011] [Accepted: 07/17/2011] [Indexed: 01/14/2023]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease and it poses an ever-increasing burden to an aging population. Several loci responsible for the rare, autosomal dominant form of AD have been identified (APP, PS1 and PS2), and these have facilitated the development of the amyloid cascade hypothesis of AD aetiology. The late onset form of the disease (LOAD) is poorly defined genetically, and up until recently the only known risk factor was the ε4 allele of APOE. Recent genome-wide association studies (GWAS) have identified common genetic variants that increase risk of LOAD. Two of the genes highlighted in these studies, CLU and CR1, suggest a role for the complement system in the aetiology of AD. In this review we analyse the evidence for an involvement of complement in AD. In particular we focus on one gene, CR1, and its role in the complement cascade. CR1 is a receptor for the complement fragments C3b and C4b and is expressed on many different cell types, particularly in the circulatory system. We look at the evidence for genetic polymorphisms in the gene and the possible physiological effects of these well-documented changes. Finally, we discuss the possible impact of CR1 genetic polymorphisms in relation to the amyloid cascade hypothesis of AD and the way in which CR1 may lead to AD pathogenesis.
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Affiliation(s)
- Helen Crehan
- Reta Lila Weston Laboratories and Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, United Kingdom
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39
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Veerhuis R, Nielsen HM, Tenner AJ. Complement in the brain. Mol Immunol 2011; 48:1592-603. [PMID: 21546088 DOI: 10.1016/j.molimm.2011.04.003] [Citation(s) in RCA: 293] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 04/04/2011] [Accepted: 04/04/2011] [Indexed: 01/24/2023]
Abstract
The brain is considered to be an immune privileged site, because the blood-brain barrier limits entry of blood borne cells and proteins into the central nervous system (CNS). As a result, the detection and clearance of invading microorganisms and senescent cells as well as surplus neurotransmitters, aged and glycated proteins, in order to maintain a healthy environment for neuronal and glial cells, is largely confined to the innate immune system. In recent years it has become clear that many factors of innate immunity are expressed throughout the brain. Neuronal and glial cells express Toll like receptors as well as complement receptors, and virtually all complement components can be locally produced in the brain, often in response to injury or developmental cues. However, as inflammatory reactions could interfere with proper functioning of the brain, tight and fine tuned regulatory mechanisms are warranted. In age related diseases, such as Alzheimer's disease (AD), accumulating amyloid proteins elicit complement activation and a local, chronic inflammatory response that leads to attraction and activation of glial cells that, under such activation conditions, can produce neurotoxic substances, including pro-inflammatory cytokines and oxygen radicals. This process may be exacerbated by a disturbed balance between complement activators and complement regulatory proteins such as occurs in AD, as the local synthesis of these proteins is differentially regulated by pro-inflammatory cytokines. Much knowledge about the role of complement in neurodegenerative diseases has been derived from animal studies with transgenic overexpressing or knockout mice for specific complement factors or receptors. These studies have provided insight into the potential therapeutic use of complement regulators and complement receptor antagonists in chronic neurodegenerative diseases as well as in acute conditions, such as stroke. Interestingly, recent animal studies have also indicated that complement activation products are involved in brain development and synapse formation. Not only are these findings important for the understanding of how brain development and neural network formation is organized, it may also give insights into the role of complement in processes of neurodegeneration and neuroprotection in the injured or aged and diseased adult central nervous system, and thus aid in identifying novel and specific targets for therapeutic intervention.
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Affiliation(s)
- Robert Veerhuis
- Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands.
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40
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Role for complement in the development of seizures following acute viral infection. J Virol 2010; 84:6452-60. [PMID: 20427530 DOI: 10.1128/jvi.00422-10] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Complement, part of the innate immune system, acts to remove pathogens and unwanted host material. Complement is known to function in all tissues, including the central nervous system (CNS). In this study, we demonstrated the importance of the complement system within the CNS in the development of behavioral seizures following Theiler's murine encephalomyelitis virus (TMEV) infection. C57BL/6 mice, deficient in complement component C3, developed significantly fewer behavioral seizures following TMEV infection, whereas mice depleted of complement component C3 in the periphery through treatment with cobra venom factor had a seizure rate comparable to that of control mice. These studies indicate that C3 participates in the induction of acute seizures during viral encephalitis.
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41
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Kolev MV, Tediose T, Sivasankar B, Harris CL, Thome J, Morgan BP, Donev RM. Upregulating CD59: a new strategy for protection of neurons from complement-mediated degeneration. THE PHARMACOGENOMICS JOURNAL 2009; 10:12-9. [DOI: 10.1038/tpj.2009.52] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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42
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Shinjyo N, Ståhlberg A, Dragunow M, Pekny M, Pekna M. Complement-Derived Anaphylatoxin C3a Regulates In Vitro Differentiation and Migration of Neural Progenitor Cells. Stem Cells 2009; 27:2824-32. [DOI: 10.1002/stem.225] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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43
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Woodruff TM, Ager RR, Tenner AJ, Noakes PG, Taylor SM. The role of the complement system and the activation fragment C5a in the central nervous system. Neuromolecular Med 2009; 12:179-92. [PMID: 19763906 DOI: 10.1007/s12017-009-8085-y] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 08/25/2009] [Indexed: 12/28/2022]
Abstract
The complement system is a pivotal component of the innate immune system which protects the host from infection and injury. Complement proteins can be induced in all cell types within the central nervous system (CNS), where the pathway seems to play similar roles in host defense. Complement activation produces the C5 cleavage fragment C5a, a potent inflammatory mediator, which recruits and activates immune cells. The primary cellular receptor for C5a, the C5a receptor (CD88), has been reported to be on all CNS cells, including neurons and glia, suggesting a functional role for C5a in the CNS. A second receptor for C5a, the C5a-like receptor 2 (C5L2), is also expressed on these cells; however, little is currently known about its potential role in the CNS. The potent immune and inflammatory actions of complement activation are necessary for host defense. However, if over-activated, or left unchecked it promotes tissue injury and contributes to brain disease pathology. Thus, complement activation, and subsequent C5a generation, is thought to play a significant role in the progression of CNS disease. Paradoxically, complement may also exert a neuroprotective role in these diseases by aiding in the elimination of aggregated and toxic proteins and debris which are a principal hallmark of many of these diseases. This review will discuss the expression and known roles for complement in the CNS, with a particular focus on the pro-inflammatory end-product, C5a. The possible overarching role for C5a in diseases of the CNS is reviewed, and the therapeutic potential of blocking C5a/CD88 interaction is evaluated.
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Affiliation(s)
- Trent M Woodruff
- School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, 4072, Australia.
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44
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Kallio SP, Jakkula E, Purcell S, Suvela M, Koivisto K, Tienari PJ, Elovaara I, Pirttilä T, Reunanen M, Bronnikov D, Viander M, Meri S, Hillert J, Lundmark F, Harbo HF, Lorentzen AR, De Jager PL, Daly MJ, Hafler DA, Palotie A, Peltonen L, Saarela J. Use of a genetic isolate to identify rare disease variants: C7 on 5p associated with MS. Hum Mol Genet 2009; 18:1670-83. [PMID: 19221116 DOI: 10.1093/hmg/ddp073] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Large case-control genome-wide association studies primarily expose common variants contributing to disease pathogenesis with modest effects. Thus, alternative strategies are needed to tackle rare, possibly more penetrant alleles. One strategy is to use special populations with a founder effect and isolation, resulting in allelic enrichment. For multiple sclerosis such a unique setting is reported in Southern Ostrobothnia in Finland, where the prevalence and familial occurrence of multiple sclerosis (MS) are exceptionally high. Here, we have studied one of the best replicated MS loci, 5p, and monitored for haplotypes shared among 72 regional MS cases, the majority of which are genealogically distantly related. The haplotype analysis over the 45 Mb region, covering the linkage peak identified in Finnish MS families, revealed only modest association at IL7R (P = 0.04), recently implicated in MS, whereas most significant association was found with one haplotype covering the C7-FLJ40243 locus (P = 0.0001), 5.1 Mb centromeric of IL7R. The finding was validated in an independent sample from the isolate and resulted in an odds ratio of 2.73 (P = 0.000003) in the combined data set. The identified relatively rare risk haplotype contains C7 (complement component 7), an important player of the innate immune system. Suggestive association with alleles of the region was seen also in more heterogeneous populations. Interestingly, also the complement activity correlated with the identified risk haplotype. These results suggest that the MS predisposing locus on 5p is more complex than assumed and exemplify power of population isolates in the identification of rare disease alleles.
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Affiliation(s)
- Suvi P Kallio
- Finnish Institute for Molecular Medicine, Biomedicum, Helsinki, Finland
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45
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Walker DG, Dalsing-Hernandez JE, Lue LF. Human postmortem brain-derived cerebrovascular smooth muscle cells express all genes of the classical complement pathway: a potential mechanism for vascular damage in cerebral amyloid angiopathy and Alzheimer's disease. Microvasc Res 2007; 75:411-9. [PMID: 18048067 DOI: 10.1016/j.mvr.2007.10.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2006] [Revised: 09/27/2007] [Accepted: 10/12/2007] [Indexed: 10/22/2022]
Abstract
Deposition of amyloid around blood vessels, known as cerebral amyloid angiopathy (CAA), is a major pathological feature found in the majority of Alzheimer's disease (AD) cases, and activated complement fragments have been detected on CAA deposits in AD brains. In this study, we demonstrate for the first time that human cerebrovascular smooth muscle cells (HCSMC) isolated from cortical vessels derived from postmortem brains can express mRNAs for complement genes C1qB, C1r, C1s, C2, C3, C4, C5, C6, C7, C8 and C9, the components of the classical complement pathway. Secretion of the corresponding complement proteins for these genes was also demonstrated, except for C1q and C5. Of particular significance was the observation that treatment of HCSMC with aggregated amyloid beta (Abeta) 1-42 increased expression of complement C3 mRNA and increased release of C3 protein. Abeta treatment of HCSMC also increased expression of C6 mRNA. Interferon-gamma induced expression and release of complement C1r, C1s, C2 and C4. As HCSMC are closely associated with Abeta deposits in vessels in the brain, their production of complement proteins could amplify the proinflammatory effects of amyloid in the perivascular environment, further compromising brain vascular integrity.
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MESH Headings
- Aged, 80 and over
- Alzheimer Disease/metabolism
- Alzheimer Disease/pathology
- Amyloid beta-Peptides/pharmacology
- Brain/blood supply
- Cadaver
- Cells, Cultured
- Cerebral Amyloid Angiopathy/metabolism
- Cerebral Amyloid Angiopathy/pathology
- Complement System Proteins/genetics
- Complement System Proteins/metabolism
- Culture Media, Conditioned/chemistry
- Culture Media, Conditioned/metabolism
- Gene Expression
- Humans
- Interferon-gamma/pharmacology
- Muscle, Smooth, Vascular/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Postmortem Changes
- RNA, Messenger/metabolism
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Affiliation(s)
- Douglas G Walker
- Laboratory of Neuroinflammation, Sun Health Research Institute, Sun City, Arizona, USA.
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Li K, Sacks SH, Zhou W. The relative importance of local and systemic complement production in ischaemia, transplantation and other pathologies. Mol Immunol 2007; 44:3866-74. [PMID: 17768105 DOI: 10.1016/j.molimm.2007.06.006] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Indexed: 10/22/2022]
Abstract
Besides a critical role in innate host defence, complement activation contributes to inflammatory and immunological responses in a number of pathological conditions. Many tissues outside the liver (the primary source of complement) synthesise a variety of complement proteins, either constitutively or response to noxious stimuli. The significance of this local synthesis of complement has become clearer as a result of functional studies. It revealed that local production not only contributes to the systemic pool of complement but also influences local tissue injury and provides a link with the antigen-specific immune response. Extravascular production of complement seems particularly important at locations with poor access to circulating components and at sites of tissue stress responses, notably portals of entry of invasive microbes, such as interstitial spaces and renal tubular epithelial surfaces. Understanding the relative importance of local and systemic complement production at such locations could help to explain the differential involvement of complement in organ-specific pathology and inform the design of complement-based therapy. Here, we will describe the lessons we have learned over the last decade about the local synthesis of complement and its association with inflammatory and immunological diseases, placing emphasis on the role of local synthesis of complement in organ transplantation.
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Affiliation(s)
- Ke Li
- MRC Centre for Transplantation and Department of Nephrology and Transplantation, King's College London School of Medicine at Guy's Hospital, London, UK
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47
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Timár KK, Dallos A, Kiss M, Husz S, Bos JD, Asghar SS. Expression of terminal complement components by human keratinocytes. Mol Immunol 2007; 44:2578-86. [PMID: 17267037 DOI: 10.1016/j.molimm.2006.12.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 12/10/2006] [Accepted: 12/14/2006] [Indexed: 11/16/2022]
Abstract
Human keratinocytes are important constituents of the skin immune system. They produce several cytokines, chemokines as well as some complement proteins. As regards soluble complement proteins, so far keratinocytes have been shown to synthesize only C3, factor B, factor H and factor I. Synthesis and regulation of synthesis of other complement proteins has not yet been studied. Here we studied the synthesis of terminal complement components, C5-C9 by human keratinocytes. We also studied the regulation of terminal complement synthesis in keratinocytes by several cytokines, namely, IL-1alpha, IL-2, IL-6, TGF-beta1, TNF-alpha, and IFN-gamma. Human keratinocytes constitutively expressed C5, C7, C8gamma and C9 mRNA but not C6, C8alpha and C8beta mRNA. They released C7 and C9, but not C5, C6 and C8. None of the cytokines tested had any influence on the synthesis of terminal components except TNF-alpha, which strongly upregulated C9 production. In conclusion, we demonstrate that keratinocytes are capable of synthesizing some of the terminal complement components and that the synthesis of C9 is regulated by TNF-alpha.
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Affiliation(s)
- Krisztina K Timár
- Department of Dermatology, Academic Medical Center, University of Amsterdam, P.O. Box 22700, 1100 DE Amsterdam, The Netherlands.
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48
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Abstract
Neuroinflammation is a host defense mechanism associated with neutralization of an insult and restoration of normal structure and function of brain. Neuroinflammation is a hallmark of all major CNS diseases. The main mediators of neuroinflammation are microglial cells. These cells are activated during a CNS injury. Microglial cells initiate a rapid response that involves cell migration, proliferation, release of cytokines/chemokines and trophic and/or toxic effects. Cytokines/chemokines stimulate phospholipases A2 and cyclooxygenases. This results in breakdown of membrane glycerophospholipids with the release of arachidonic acid (AA) and docosahexaenoic acid (DHA). Oxidation of AA produces pro-inflammatory prostaglandins, leukotrienes, and thromboxanes. One of the lyso-glycerophospholipids, the other products of reactions catalyzed by phospholipase A2, is used for the synthesis of pro-inflammatory platelet-activating factor. These pro-inflammatory mediators intensify neuroinflammation. Lipoxin, an oxidized product of AA through 5-lipoxygenase, is involved in the resolution of inflammation and is anti-inflammatory. Docosahexaenoic acid is metabolized to resolvins and neuroprotectins. These lipid mediators inhibit the generation of prostaglandins, leukotrienes, and thromboxanes. Levels of prostaglandins, leukotrienes, and thromboxanes are markedly increased in acute neural trauma and neurodegenerative diseases. Docosahexaenoic acid and its lipid mediators prevent neuroinflammation by inhibiting transcription factor NFkappaB, preventing cytokine secretion, blocking the synthesis of prostaglandins, leukotrienes, and thromboxanes, and modulating leukocyte trafficking. Depending on its timing and magnitude in brain tissue, inflammation serves multiple purposes. It is involved in the protection of uninjured neurons and removal of degenerating neuronal debris and also in assisting repair and recovery processes. The dietary ratio of AA to DHA may affect neurodegeneration associated with acute neural trauma and neurodegenerative diseases. The dietary intake of docosahexaenoic acid offers the possibility of counter-balancing the harmful effects of high levels of AA-derived pro-inflammatory lipid mediators.
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Affiliation(s)
- Akhlaq A Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
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Role of inflammation and cellular stress in brain injury and central nervous system diseases. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.cnr.2006.09.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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50
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Gorter JA, van Vliet EA, Aronica E, Breit T, Rauwerda H, Lopes da Silva FH, Wadman WJ. Potential new antiepileptogenic targets indicated by microarray analysis in a rat model for temporal lobe epilepsy. J Neurosci 2006; 26:11083-110. [PMID: 17065450 PMCID: PMC6674659 DOI: 10.1523/jneurosci.2766-06.2006] [Citation(s) in RCA: 248] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
To get insight into the mechanisms that may lead to progression of temporal lobe epilepsy, we investigated gene expression during epileptogenesis in the rat. RNA was obtained from three different brain regions [CA3, entorhinal cortex (EC), and cerebellum (CB)] at three different time points after electrically induced status epilepticus (SE): acute phase [group D (1 d)], latent period [group W (1 week)], and chronic epileptic period [group M (3-4 months)]. A group that was stimulated but that had not experienced SE and later epilepsy was also included (group nS). Gene expression analysis was performed using the Affymetrix Gene Chip System (RAE230A). We used GENMAPP and Gene Ontology to identify global biological trends in gene expression data. The immune response was the most prominent process changed during all three phases of epileptogenesis. Synaptic transmission was a downregulated process during the acute and latent phases. GABA receptor subunits involved in tonic inhibition were persistently downregulated. These changes were observed mostly in both CA3 and EC but not in CB. Rats that were stimulated but that did not develop spontaneous seizures later on had also some changes in gene expression, but this was not reflected in a significant change of a biological process. These data suggest that the targeting of specific genes that are involved in these biological processes may be a promising strategy to slow down or prevent the progression of epilepsy. Especially genes related to the immune response, such as complement factors, interleukins, and genes related to prostaglandin synthesis and coagulation pathway may be interesting targets.
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Affiliation(s)
- Jan A Gorter
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 SM, Amsterdam, The Netherlands.
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