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Galbraith MD, Rachubinski AL, Smith KP, Araya P, Waugh KA, Enriquez-Estrada B, Worek K, Granrath RE, Kinning KT, Paul Eduthan N, Ludwig MP, Hsieh EW, Sullivan KD, Espinosa JM. Multidimensional definition of the interferonopathy of Down syndrome and its response to JAK inhibition. SCIENCE ADVANCES 2023; 9:eadg6218. [PMID: 37379383 PMCID: PMC10306300 DOI: 10.1126/sciadv.adg6218] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 05/25/2023] [Indexed: 06/30/2023]
Abstract
Individuals with Down syndrome (DS) display chronic hyperactivation of interferon signaling. However, the clinical impacts of interferon hyperactivity in DS are ill-defined. Here, we describe a multiomics investigation of interferon signaling in hundreds of individuals with DS. Using interferon scores derived from the whole blood transcriptome, we defined the proteomic, immune, metabolic, and clinical features associated with interferon hyperactivity in DS. Interferon hyperactivity associates with a distinct proinflammatory phenotype and dysregulation of major growth signaling and morphogenic pathways. Individuals with the highest interferon activity display the strongest remodeling of the peripheral immune system, including increased cytotoxic T cells, B cell depletion, and monocyte activation. Interferon hyperactivity accompanies key metabolic changes, most prominently dysregulated tryptophan catabolism. High interferon signaling stratifies a subpopulation with elevated rates of congenital heart disease and autoimmunity. Last, a longitudinal case study demonstrated that JAK inhibition normalizes interferon signatures with therapeutic benefit in DS. Together, these results justify the testing of immune-modulatory therapies in DS.
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Affiliation(s)
- Matthew D. Galbraith
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Angela L. Rachubinski
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Pediatrics, Section of Developmental Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Keith P. Smith
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Paula Araya
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Katherine A. Waugh
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Belinda Enriquez-Estrada
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Kayleigh Worek
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Ross E. Granrath
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Kohl T. Kinning
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Neetha Paul Eduthan
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Michael P. Ludwig
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Elena W. Y. Hsieh
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Pediatrics, Division of Allergy/Immunology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Kelly D. Sullivan
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Pediatrics, Section of Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Joaquin M. Espinosa
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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2
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Down syndrome and type I interferon: not so simple. Curr Opin Immunol 2021; 72:196-205. [PMID: 34174697 DOI: 10.1016/j.coi.2021.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/02/2021] [Accepted: 06/08/2021] [Indexed: 12/12/2022]
Abstract
Down syndrome (DS) is characterized by a collection of clinical features including intellectual disability, congenital malformations, and susceptibility to infections and autoimmune diseases. While the presence of an extra chromosome 21 is known to cause DS, the precise genetic annotation linked to specific clinical features is largely missing. However, there is growing evidence that two genes located on chromosome 21, IFNAR1 and IFNAR2, play an important role in disease pathogenesis. These genes encode the two subunits of the receptor for type I interferons (IFN-I), a group of potent antiviral and pro-inflammatory cytokines. Human monogenic diseases caused by uncontrolled IFN-I production and response have been well characterized, and they clinically overlap with DS but also have notable differences. Herein, we review the literature characterizing the role of IFN-I in DS and compare and contrast DS to other IFN-mediated conditions. The existing IFN-I literature serves as a rich resource for testable hypotheses to elucidate disease mechanisms in DS and is likely to open novel therapeutic avenues.
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Roy ER, Cao W. Antiviral Immune Response in Alzheimer's Disease: Connecting the Dots. Front Neurosci 2020; 14:577744. [PMID: 33132831 PMCID: PMC7561672 DOI: 10.3389/fnins.2020.577744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/08/2020] [Indexed: 11/15/2022] Open
Abstract
Alzheimer’s disease (AD) represents an enormous public health challenge currently and with increasing urgency in the coming decades. Our understanding of the etiology and pathogenesis of AD is rather incomplete, which is manifested in stagnated therapeutic developments. Apart from the well-established Amyloid Hypothesis of AD, gaining traction in recent years is the Pathogen Hypothesis, which postulates a causal role of infectious agents in the development of AD. Particularly, infection by viruses, among a diverse range of microorganisms, has been implicated. Recently, we described a prominent antiviral immune response in human AD brains as well as murine amyloid beta models, which has consequential effects on neuropathology. Such findings expectedly allude to the question about viral infections and AD. In this Perspective, we would like to discuss the molecular mechanism underlying the antiviral immune response, highlight how such pathway directly promotes AD pathogenesis, and depict a multilayered connection between antiviral immune response and other agents and factors relevant to AD. By tying together these threads of evidence, we provide a cohesive perspective on the uprising of antiviral immune response in AD.
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Affiliation(s)
- Ethan R Roy
- Huffington Center on Aging and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Wei Cao
- Huffington Center on Aging and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
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4
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Duval N, Vacano GN, Patterson D. Rapamycin Treatment Ameliorates Age-Related Accumulation of Toxic Metabolic Intermediates in Brains of the Ts65Dn Mouse Model of Down Syndrome and Aging. Front Aging Neurosci 2018; 10:263. [PMID: 30237765 PMCID: PMC6135881 DOI: 10.3389/fnagi.2018.00263] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 08/14/2018] [Indexed: 01/22/2023] Open
Abstract
Down syndrome (DS), caused by trisomy of chromosome 21, is the most common genetic cause of intellectual disability. Individuals with DS exhibit changes in neurochemistry and neuroanatomy that worsen with age, neurological delay in learning and memory, and predisposition to Alzheimer's disease. The Ts65Dn mouse is the best characterized model of DS and has many features reminiscent of DS, including developmental anomalies and age-related neurodegeneration. The mouse carries a partial triplication of mouse chromosome 16 containing roughly 100 genes syntenic to human chromosome 21 genes. We hypothesized that there would be differences in brain metabolites with trisomy and age, and that long-term treatment with rapamycin, mechanistic target of rapamycin (mTOR) inhibitor and immunosuppressant, would correct these differences. Using HPLC coupled with electrochemical detection, we identified differences in levels of metabolites involved in dopaminergic, serotonergic, and kynurenine pathways in trisomic mice that are exacerbated with age. These include homovanillic acid, norepinephrine, and kynurenine. In addition, we demonstrate that prolonged treatment with rapamycin reduces accumulation of toxic metabolites (such as 6-hydroxymelatonin and 3-hydroxykynurenine) in aged mice.
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Affiliation(s)
- Nathan Duval
- Department of Biological Sciences, Knoebel Institute for Healthy Aging, and Eleanor Roosevelt Institute, University of Denver, Denver, CO, United States
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5
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Hamlett ED, Ledreux A, Potter H, Chial HJ, Patterson D, Espinosa JM, Bettcher BM, Granholm AC. Exosomal biomarkers in Down syndrome and Alzheimer's disease. Free Radic Biol Med 2018; 114:110-121. [PMID: 28882786 PMCID: PMC6135098 DOI: 10.1016/j.freeradbiomed.2017.08.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 08/30/2017] [Accepted: 08/31/2017] [Indexed: 02/07/2023]
Abstract
Every person with Down syndrome (DS) has the characteristic features of Alzheimer's disease (AD) neuropathology in their brain by the age of forty, and most go on to develop AD dementia. Since people with DS show highly variable levels of baseline function, it is often difficult to identify early signs of dementia in this population. The discovery of blood biomarkers predictive of dementia onset and/or progression in DS is critical for developing effective clinical diagnostics. Our recent studies show that neuron-derived exosomes, which are small extracellular vesicles secreted by most cells in the body, contain elevated levels of amyloid-beta peptides and phosphorylated-Tau that could indicate a preclinical AD phase in people with DS starting in childhood. We also found that the relative levels of these biomarkers were altered following dementia onset. Exosome release and signaling are dependent on cellular redox homeostasis as well as on inflammatory processes, and exosomes may be involved in the immune response, suggesting a dual role as both triggers of inflammation in the brain and propagators of inflammatory signals between brain regions. Based on recently reported connections between inflammatory processes and exosome release, the elevated neuroinflammatory state observed in people with DS may affect exosomal AD biomarkers. Herein, we discuss findings from studies of people with DS, people with DS and AD (DS-AD), and mouse models of DS showing new connections between neuroinflammatory pathways, oxidative stress, exosomes, and exosome-mediated signaling, which may inform future AD diagnostics, preventions, and treatments in the DS population as well as in the general population.
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Affiliation(s)
- Eric D Hamlett
- Knoebel Institute for Healthy Aging and the Department of Biological Sciences, University of Denver, Denver, CO, USA; Medical University of South Carolina, Charleston, SC, USA
| | - Aurélie Ledreux
- Knoebel Institute for Healthy Aging and the Department of Biological Sciences, University of Denver, Denver, CO, USA
| | - Huntington Potter
- Rocky Mountain Alzheimer's Disease Center, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Department of Neurology, University of Colorado Anschutz Medical Campus, Denver, CO, USA
| | - Heidi J Chial
- Rocky Mountain Alzheimer's Disease Center, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Department of Neurology, University of Colorado Anschutz Medical Campus, Denver, CO, USA
| | - David Patterson
- Knoebel Institute for Healthy Aging and the Department of Biological Sciences, University of Denver, Denver, CO, USA
| | - Joaquin M Espinosa
- Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Department of Pharmacology, University of Colorado Anschutz Medical Campus, Denver, CO, USA
| | - Brianne M Bettcher
- Rocky Mountain Alzheimer's Disease Center, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Department of Neurology, University of Colorado Anschutz Medical Campus, Denver, CO, USA; Department of Neurosurgery, University of Colorado Anschutz Medical Campus, Denver, CO, USA
| | - Ann-Charlotte Granholm
- Knoebel Institute for Healthy Aging and the Department of Biological Sciences, University of Denver, Denver, CO, USA; Medical University of South Carolina, Charleston, SC, USA.
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Torres MD, Garcia O, Tang C, Busciglio J. Dendritic spine pathology and thrombospondin-1 deficits in Down syndrome. Free Radic Biol Med 2018; 114:10-14. [PMID: 28965914 PMCID: PMC7185223 DOI: 10.1016/j.freeradbiomed.2017.09.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 09/25/2017] [Accepted: 09/26/2017] [Indexed: 11/27/2022]
Abstract
Abnormal dendritic spine structure and function is one of the most prominent features associated with neurodevelopmental disorders including Down syndrome (DS). Defects in both spine morphology and spine density may underlie alterations in neuronal and synaptic plasticity, ultimately affecting cognitive ability. Here we briefly examine the role of astrocytes in spine alterations and more specifically the involvement of astrocyte-secreted thrombospondin 1 (TSP-1) deficits in spine and synaptic pathology in DS.
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Affiliation(s)
- Maria D Torres
- Department of Neurobiology and Behavior, Institute for Memory Impairments and Neurological Disorders (iMIND), and Center for the Neurobiology of Learning and Memory (CNLM), University of California, Irvine, CA 92697, United States
| | - Octavio Garcia
- Facultad de Psicología, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Cindy Tang
- Department of Neurobiology and Behavior, Institute for Memory Impairments and Neurological Disorders (iMIND), and Center for the Neurobiology of Learning and Memory (CNLM), University of California, Irvine, CA 92697, United States
| | - Jorge Busciglio
- Department of Neurobiology and Behavior, Institute for Memory Impairments and Neurological Disorders (iMIND), and Center for the Neurobiology of Learning and Memory (CNLM), University of California, Irvine, CA 92697, United States.
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7
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Sullivan KD, Lewis HC, Hill AA, Pandey A, Jackson LP, Cabral JM, Smith KP, Liggett LA, Gomez EB, Galbraith MD, DeGregori J, Espinosa JM. Trisomy 21 consistently activates the interferon response. eLife 2016; 5. [PMID: 27472900 PMCID: PMC5012864 DOI: 10.7554/elife.16220] [Citation(s) in RCA: 183] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 07/28/2016] [Indexed: 12/12/2022] Open
Abstract
Although it is clear that trisomy 21 causes Down syndrome, the molecular events acting downstream of the trisomy remain ill defined. Using complementary genomics analyses, we identified the interferon pathway as the major signaling cascade consistently activated by trisomy 21 in human cells. Transcriptome analysis revealed that trisomy 21 activates the interferon transcriptional response in fibroblast and lymphoblastoid cell lines, as well as circulating monocytes and T cells. Trisomy 21 cells show increased induction of interferon-stimulated genes and decreased expression of ribosomal proteins and translation factors. An shRNA screen determined that the interferon-activated kinases JAK1 and TYK2 suppress proliferation of trisomy 21 fibroblasts, and this defect is rescued by pharmacological JAK inhibition. Therefore, we propose that interferon activation, likely via increased gene dosage of the four interferon receptors encoded on chromosome 21, contributes to many of the clinical impacts of trisomy 21, and that interferon antagonists could have therapeutic benefits. DOI:http://dx.doi.org/10.7554/eLife.16220.001 Our genetic information is contained within structures called chromosomes. Down syndrome is caused by the genetic condition known as trisomy 21, in which a person is born with an extra copy of chromosome 21. This extra chromosome affects human development in many ways, including causing neurological problems and stunted growth. Trisomy 21 makes individuals more susceptible to certain diseases, such as Alzheimer’s disease and autoimmune disorders – where the immune system attacks healthy cells in the body – while protecting them from tumors and some other conditions. Since cells with trisomy 21 have an extra copy of every single gene on chromosome 21, it is expected that these genes should be more highly expressed – that is, the products of these genes should be present at higher levels inside cells. However, it was not clear which genes on other chromosomes are also affected by trisomy 21. Sullivan et al. aimed to identify which genes are affected by trisomy 21 by studying samples collected from a variety of individuals with, and without, this condition. Four genes in chromosome 21 encode proteins that recognize signal molecules called interferons, which are produced by cells in response to viral or bacterial infection. Interferons act on neighboring cells to regulate genes that prevent the spread of the infection, shut down the production of proteins and activate the immune system. Sullivan et al. show that cells with trisomy 21 produce high levels of genes that are activated by interferons and lower levels of genes required for protein production. In other words, the cells of people with Down syndrome are constantly fighting a viral infection that does not exist. Constant activation of interferon signaling could explain many aspects of Down syndrome, including neurological problems and protection against tumors. The next steps are to fully define the role of interferon signaling in the development of Down syndrome, and to find out whether drugs that block the action of interferons could have therapeutic benefits. DOI:http://dx.doi.org/10.7554/eLife.16220.002
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Affiliation(s)
- Kelly D Sullivan
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Pharmacology, University of Colorado School of Medicine, Aurora, United States.,Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
| | - Hannah C Lewis
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Pharmacology, University of Colorado School of Medicine, Aurora, United States
| | - Amanda A Hill
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Pharmacology, University of Colorado School of Medicine, Aurora, United States
| | - Ahwan Pandey
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Pharmacology, University of Colorado School of Medicine, Aurora, United States.,Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
| | - Leisa P Jackson
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
| | - Joseph M Cabral
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
| | - Keith P Smith
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States
| | - L Alexander Liggett
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, United States
| | - Eliana B Gomez
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
| | - Matthew D Galbraith
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Pharmacology, University of Colorado School of Medicine, Aurora, United States.,Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
| | - James DeGregori
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, United States.,Department of Pediatrics, University of Colorado School of Medicine, Aurora, United States.,Integrated Department of Immunology, University of Colorado School of Medicine, Aurora, United States.,Section of Hematology, University of Colorado School of Medicine, Aurora, United States.,Department of Medicine, University of Colorado School of Medicine, Aurora, United States
| | - Joaquín M Espinosa
- Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Aurora, United States.,Department of Pharmacology, University of Colorado School of Medicine, Aurora, United States.,Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, United States.,Howard Hughes Medical Institute, Chevy Chase, United States
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8
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Potential Role of JAK-STAT Signaling Pathway in the Neurogenic-to-Gliogenic Shift in Down Syndrome Brain. Neural Plast 2016; 2016:7434191. [PMID: 26881131 PMCID: PMC4737457 DOI: 10.1155/2016/7434191] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 11/15/2015] [Accepted: 11/17/2015] [Indexed: 01/09/2023] Open
Abstract
Trisomy of human chromosome 21 in Down syndrome (DS) leads to several phenotypes, such as mild-to-severe intellectual disability, hypotonia, and craniofacial dysmorphisms. These are fundamental hallmarks of the disorder that affect the quality of life of most individuals with DS. Proper brain development involves meticulous regulation of various signaling pathways, and dysregulation may result in abnormal neurodevelopment. DS brain is characterized by an increased number of astrocytes with reduced number of neurons. In mouse models for DS, the pool of neural progenitor cells commits to glia rather than neuronal cell fate in the DS brain. However, the mechanism(s) and consequences of this slight neurogenic-to-gliogenic shift in DS brain are still poorly understood. To date, Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling has been proposed to be crucial in various developmental pathways, especially in promoting astrogliogenesis. Since both human and mouse models of DS brain exhibit less neurons and a higher percentage of cells with astrocytic phenotypes, understanding the role of JAK-STAT signaling in DS brain development will provide novel insight into its role in the pathogenesis of DS brain and may serve as a potential target for the development of effective therapy to improve DS cognition.
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9
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Wilcock DM, Griffin WST. Down's syndrome, neuroinflammation, and Alzheimer neuropathogenesis. J Neuroinflammation 2013; 10:84. [PMID: 23866266 PMCID: PMC3750399 DOI: 10.1186/1742-2094-10-84] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 05/28/2013] [Indexed: 12/26/2022] Open
Abstract
Down syndrome (DS) is the result of triplication of chromosome 21 (trisomy 21) and is the prevailing cause of mental retardation. In addition to the mental deficiencies and physical anomalies noted at birth, triplication of chromosome 21 gene products results in the neuropathological and cognitive changes of Alzheimer's disease (AD). Mapping of the gene that encodes the precursor protein (APP) of the β-amyloid (Aβ) present in the Aβ plaques in both AD and DS to chromosome 21 was strong evidence that this chromosome 21 gene product was a principal neuropathogenic culprit in AD as well as DS. The discovery of neuroinflammatory changes, including dramatic proliferation of activated glia overexpressing a chromosome 2 gene product--the pluripotent immune cytokine interleukin-1 (IL-1)--and a chromosome 21 gene product--S100B--in the brains of fetuses, neonates, and children with DS opened the possibility that early events in Alzheimer pathogenesis were driven by cytokines. The specific chromosome 21 gene products and the complexity of the mechanisms they engender that give rise to the neuroinflammatory responses noted in fetal development of the DS brain and their potential as accelerators of Alzheimer neuropathogenesis in DS are topics of this review, particularly as they relate to development and propagation of neuroinflammation, the consequences of which are recognized clinically and neuropathologically as Alzheimer's disease.
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Affiliation(s)
- Donna M Wilcock
- Department of Physiology, Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40536, USA
| | - W Sue T Griffin
- Donald W. Reynolds Department of Geriatrics, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, 629 Jack Stephens Dr., Little Rock, AR 72205, USA
- The Geriatric Research Education Clinical Center, Central Arkansas HealthCare System, Little Rock, AR, USA
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10
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Neuroinflammation in the aging down syndrome brain; lessons from Alzheimer's disease. Curr Gerontol Geriatr Res 2012; 2012:170276. [PMID: 22454637 PMCID: PMC3290800 DOI: 10.1155/2012/170276] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 11/15/2011] [Indexed: 12/25/2022] Open
Abstract
Down syndrome (DS) is the most genetic cause of mental retardation and is caused by the triplication of chromosome 21. In addition to the disabilities caused early in life, DS is also noted as causing Alzheimer's-disease-like pathological changes in the brain, leading to 50-70% of DS patients showing dementia by 60-70 years of age. Inflammation is a complex process that has a key role to play in the pathogenesis of Alzheimer's disease. There is relatively little understood about inflammation in the DS brain and how the genetics of DS may alter this inflammatory response and change the course of disease in the DS brain. The goal of this review is to highlight our current understanding of inflammation in Alzheimer's disease and predict how inflammation may affect the pathology of the DS brain based on this information and the known genetic changes that occur due to triplication of chromosome 21.
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11
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Dafny N, Yang PB. Interferon and the central nervous system. Eur J Pharmacol 2005; 523:1-15. [PMID: 16226745 DOI: 10.1016/j.ejphar.2005.08.029] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2005] [Revised: 07/01/2005] [Accepted: 08/18/2005] [Indexed: 01/14/2023]
Abstract
Interferons (IFNs) were discovered as natural antiviral substances produced during viral infection and were initially characterized for their ability to "interfere" with viral replication, slow cell proliferation, and profound alteration of immunity. The IFNs are synthesized and secreted by monocytes, macrophages, T-lymphocytes, neurons, and glia cells. The different IFNs are classified into three classes: alpha, beta, and gamma. alpha-IFN produced in the brain exerts direct effects on the brain and endocrine system by activating the neurosecretory hypothalamic neurons and regulates the hypothalamic-pituitary-adrenocortical axis. IFNs modulate neurophysiological activities of many brain region involving in pain, temperature, and food intake regulation. alpha-IFN administration activates the sympathetic nerves innervating components of the immune system. IFNs may serve as regulatory mediators between the central nervous system, the immune system, and endocrine system. IFN is used as immunologic therapy to treat various hematologic malignancies and infectious ailments and autoimmune diseases.
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Affiliation(s)
- Nachum Dafny
- Department of Neurobiology and Anatomy, The University of Texas, Medical School, P.O. Box 20708, Houston, Texas 77225, USA.
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Sharova LV, Sharov AA, Sura P, Gogal RM, Smith BJ, Holladay SD. Maternal immune stimulation reduces both placental morphologic damage and down-regulated placental growth-factor and cell cycle gene expression caused by urethane: are these events related to reduced teratogenesis? Int Immunopharmacol 2003; 3:945-55. [PMID: 12810352 DOI: 10.1016/s1567-5769(03)00093-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Activation of the maternal immune system in mice decreased cleft palate caused by the chemical teratogen, urethane. Direct and indirect mechanisms for this phenomenon have been suggested, including maternal macrophages that cross the placenta to find and eliminate pre-teratogenic cells, or maternal immune proteins (cytokines) that cross placenta to alleviate or partially alleviate toxicant-mediated effects in the developing fetus. A third mechanism to explain improved fetal developmental outcome in teratogen-challenged pregnant mice might involve beneficial effects of immune stimulation on the placenta. In the present experiments, urethane treatment altered placental morphology and impaired placental function, the latter indicated by down-regulated activity of cell cycle genes and of genes encoding cytokines and growth factors. Maternal immune stimulation with either Freund's complete adjuvant (FCA) or interferon-gamma (IFNgamma) reduced morphologic damage to the placenta caused by urethane and normalized expression of several genes that were down-regulated by urethane. Urethane treatment also shifted placental cytokine gene expression toward a T cell helper 1 (Th1) profile, while immunostimulation tended to restore a Th2 profile that may be more beneficial to pregnancy and fetal development. These data suggest that the beneficial effects of maternal immune stimulation on fetal development in teratogen-exposed mice may, in part, result from improved placental structure and function.
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Affiliation(s)
- L V Sharova
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Phase II, Southgate Drive, Blacksburg, VA 24061-0442, USA
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Hallam DM, Capps NL, Travelstead AL, Brewer GJ, Maroun LE. Evidence for an interferon-related inflammatory reaction in the trisomy 16 mouse brain leading to caspase-1-mediated neuronal apoptosis. J Neuroimmunol 2000; 110:66-75. [PMID: 11024535 DOI: 10.1016/s0165-5728(00)00289-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The trisomy of human chromosome 21 (Down syndrome) is the leading genetic cause of learning difficulties in children, and predisposes this population to the early onset of the neurodegeneration of Alzheimer's disease. Down syndrome is associated with increased interferon (IFN) sensitivity resulting in unexpectedly high levels of IFN inducible gene products including Fas, complement factor C3, and neuronal HLA I which could result in a damaging inflammatory reaction in the brain. Consistent with this possibility, we report here that the trisomy 16 mouse fetus has significantly increased whole brain IFN-gamma and Fas receptor immunoreactivity and that cultured whole brain trisomy 16 mouse neurons have increased basal levels of caspase 1 activity and altered homeostasis of intracellular calcium and pH. The trisomic neurons also showed a heightened sensitivity to the increase in both Fas receptor levels and caspase 1 activity we observed when IFN-gamma was added to the neuron culture media. Because of the autoregulatory nature of IFN activity, and the IFN inducing capability of caspase-1-activated cytokine activity, our data argue in favor of the possibility of an interferon-mediated, self-perpetuating, inflammatory response in the trisomy brain that could subserve the loss of neuron viability seen in this trisomy 16 mouse model for Down syndrome.
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Affiliation(s)
- D M Hallam
- Department of Medical Microbiology and Immunology, Southern Illinois University School of Medicine, P.O. Box 19626, Springfield, IL 62794-9626, USA
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Maroun LE, Heffernan TN, Hallam DM. Partial IFN-alpha/beta and IFN-gamma receptor knockout trisomy 16 mouse fetuses show improved growth and cultured neuron viability. J Interferon Cytokine Res 2000; 20:197-203. [PMID: 10714556 DOI: 10.1089/107999000312612] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The trisomy 16 mouse fetus is a well-studied model for Down syndrome (trisomy 21), the leading genetic cause of mental retardation in the newborn population. Human chromosome 21 and mouse chromosome 16 each carry a large cluster of genes that code for components of the interferon (IFN)-alpha/beta and IFN-gamma receptors, and Down syndrome cells display significantly increased sensitivity to IFN action. We have previously reported that in utero anti-IFN IgG treatment of mice pregnant with trisomy 16 fetuses results in a significant improvement in trisomy 16 fetus growth and morphology and that anti-IFN-gamma IgG treatment can prevent the premature death of trisomy 16 fetal mouse cortical neurons in culture. We have now used IFN receptor subunit knockout mice to produce mouse fetuses that carry three No. 16 chromosomes and one copy each of disabled IFN-gamma receptor (IFNGR) and IFN-alpha/beta receptor (IFNAR-2) component genes. We report here that this partial IFN receptor knockout trisomy (PIRKOT) mouse fetus has significantly improved growth and yields cortical neurons whose viability is the equivalent of that seen in their euploid counterparts.
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Affiliation(s)
- L E Maroun
- Department of Medical Microbiology and Immunology, Southern Illinois University School of Medicine, Springfield, IL 62794-9626, USA.
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Hallam DM, Maroun LE. Anti-gamma interferon can prevent the premature death of trisomy 16 mouse cortical neurons in culture. Neurosci Lett 1998; 252:17-20. [PMID: 9756348 DOI: 10.1016/s0304-3940(98)00541-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Previous reports have indicated that human trisomy 21 and mouse trisomy 16 neurons exhibit decreased viability in culture when compared to euploid control cultures and that trisomic cells are significantly more sensitive to the anti-cellular effects of the interferons. In the study reported here, cortical neurons from euploid and trisomy 16 mouse fetuses were treated with either anti-gamma-interferon or non-specific IgG and neuron morphology and viability measured photographically. The addition of anti-gamma-interferon IgG to the culture media had no effect on euploid neurons, but significantly increased trisomy neuron viability throughout the 5-day culture period. Assay of both DNA fragmentation and phosphatidylserine externalization suggested that the trisomic neurons were undergoing apoptosis at a significantly higher rate than their euploid counterparts and that this increase in apoptosis could be almost completely prevented by addition of either ligand purified monoclonal or ligand purified polyclonal anti-gamma-interferon IgG. Taken together, these data suggest that endogenous interferon plays an important role in the premature death of the trisomy neuron.
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Affiliation(s)
- D M Hallam
- Department of Medical Microbiology and Immunology, Southern Illinois University School of Medicine, Springfield 62794-1220, USA
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