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Ma CI, Tirtorahardjo JA, Schweizer SS, Zhang J, Fang Z, Xing L, Xu M, Herman DA, Kleinman MT, McCullough BS, Barrios AM, Andrade RM. Gold(I) ion and the phosphine ligand are necessary for the anti- Toxoplasma gondii activity of auranofin. Microbiol Spectr 2024; 12:e0296823. [PMID: 38206030 PMCID: PMC10845965 DOI: 10.1128/spectrum.02968-23] [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: 08/01/2023] [Accepted: 12/08/2023] [Indexed: 01/12/2024] Open
Abstract
Auranofin, an FDA-approved drug for rheumatoid arthritis, has emerged as a promising antiparasitic medication in recent years. The gold(I) ion in auranofin is postulated to be responsible for its antiparasitic activity. Notably, aurothiomalate and aurothioglucose also contain gold(I), and, like auranofin, they were previously used to treat rheumatoid arthritis. Whether they have antiparasitic activity remains to be elucidated. Herein, we demonstrated that auranofin and similar derivatives, but not aurothiomalate and aurothioglucose, inhibited the growth of Toxoplasma gondii in vitro. We found that auranofin affected the T. gondii biological cycle (lytic cycle) by inhibiting T. gondii's invasion and triggering its egress from the host cell. However, auranofin could not prevent parasite replication once T. gondii resided within the host. Auranofin treatment induced apoptosis in T. gondii parasites, as demonstrated by its reduced size and elevated phosphatidylserine externalization (PS). Notably, the gold from auranofin enters the cytoplasm of T. gondii, as demonstrated by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDS) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS).IMPORTANCEToxoplasmosis, caused by Toxoplasma gondii, is a devastating disease affecting the brain and the eyes, frequently affecting immunocompromised individuals. Approximately 60 million people in the United States are already infected with T. gondii, representing a population at-risk of developing toxoplasmosis. Recent advances in treating cancer, autoimmune diseases, and organ transplants have contributed to this at-risk population's exponential growth. Paradoxically, treatments for toxoplasmosis have remained the same for more than 60 years, relying on medications well-known for their bone marrow toxicity and allergic reactions. Discovering new therapies is a priority, and repurposing FDA-approved drugs is an alternative approach to speed up drug discovery. Herein, we report the effect of auranofin, an FDA-approved drug, on the biological cycle of T. gondii and how both the phosphine ligand and the gold molecule determine the anti-parasitic activity of auranofin and other gold compounds. Our studies would contribute to the pipeline of candidate anti-T. gondii agents.
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Affiliation(s)
- C. I. Ma
- Department of Medicine, Division of Infectious Diseases, University of California at Irvine, Irvine, California, USA
| | - J. A. Tirtorahardjo
- Department of Microbiology and Molecular Genetics, University of California at Irvine, Irvine, California, USA
| | - S. S. Schweizer
- School of Biological Sciences; University of California at Irvine, Irvine, California, USA
| | - J. Zhang
- School of Biological Sciences; University of California at Irvine, Irvine, California, USA
| | - Z. Fang
- School of Biological Sciences; University of California at Irvine, Irvine, California, USA
| | - L. Xing
- Irvine Materials Research Institute; University of California at Irvine, Irvine, California, USA
| | - M. Xu
- Irvine Materials Research Institute; University of California at Irvine, Irvine, California, USA
| | - D. A. Herman
- Department of Medicine, Occupational and Environmental Medicine, University of California at Irvine, Irvine, California, USA
| | - M. T. Kleinman
- Department of Medicine, Occupational and Environmental Medicine, University of California at Irvine, Irvine, California, USA
| | - B. S. McCullough
- Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, Utah, USA
| | - A. M. Barrios
- Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, Utah, USA
| | - R. M. Andrade
- Department of Medicine, Division of Infectious Diseases, University of California at Irvine, Irvine, California, USA
- Department of Microbiology and Molecular Genetics, University of California at Irvine, Irvine, California, USA
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2
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Wakid MH, Alsulami MN, Farid M, El Kholy WA. Potential Anti-Toxoplasmosis Efficiency of Phoenix dactylifera Extracts Loaded on Selenium Nanoparticles. Infect Drug Resist 2023; 16:7743-7758. [PMID: 38144223 PMCID: PMC10749168 DOI: 10.2147/idr.s443047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 12/13/2023] [Indexed: 12/26/2023] Open
Abstract
Background Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii that infects humans and many types of mammals and birds. Objective To investigate the effect of selenium nanoparticles (SeNPs) and Phoenix dactylifera (Pd) extracts loaded on SeNPs as a new agent to combat chronic T. gondii infections in murine model as an alternative method to standard Spiramycin drug therapy. Methods A total of 64 female mice were randomly divided into eight groups: GI: Normal control, GII: Positive control, GIII: infected and treated with Spiramycin, GIV: infected and treated with SeNPs, GV: infected and treated with aqueous extract of Pd, GVI: infected and treated with methanolic extract of Pd, GVII: infected and treated with aqueous extract of Pd loaded on SeNPs, GVIII: infected and treated with methanolic extract of Pd loaded on SeNPs. Date palm (P. dactylifera) fruits were identified and collected from the farms of Saudi Arabia. Preparation and characterization of SeNPs were done. The parasitological, histopathological examinations and biochemical changes were evaluated in all groups. Results Parasitological results showed significant differences in GVII in comparison to GII while GVIII showed significant differences in comparison to GII and GIII. The histopathological section of the cerebral cortex showed obvious alterations in the infected compared with untreated control groups. Aqueous and methanolic extracts of P. dactylifera loaded on SeNPs treatment showed improvement that indicated by few perivascular cuffing with few inflammatory cell infiltrations. Few granule cells with mild intracellular vacuolation and edema few deformed neurons with deep pyknotic nuclei. Microglia cells expression of Iba-1 and inflammatory cytokines (IL-4, IL-10 and INF-γ) in serum of all groups was higher in GII and lowest in GVIII followed by GVII. Conclusion SeNPs and P. dactylifera extracts loaded on SeNPs could be a potent agent to combat T. gondii infections.
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Affiliation(s)
- Majed H Wakid
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Muslimah N Alsulami
- Department of Biology, College of Science, University of Jeddah, Jeddah, Saudi Arabia
| | - Mohamed Farid
- Sciences Academy of Experimental Researches, Special Scientific Foundation, Mansoura, Egypt
| | - Walaa A El Kholy
- Department of Parasitology, Faculty of Medicine for Girls, Al-Azhar University, Cairo, Egypt
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3
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Pires LB, Peixoto-Rodrigues MC, Eloi JF, Cascabulho CM, Barbosa HS, Santiago MF, Adesse D. Infection of Mouse Neural Progenitor Cells by Toxoplasma gondii Reduces Proliferation, Migration, and Neuronal Differentiation in Vitro. THE AMERICAN JOURNAL OF PATHOLOGY 2023; 193:977-994. [PMID: 37037285 DOI: 10.1016/j.ajpath.2023.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 01/27/2023] [Accepted: 03/07/2023] [Indexed: 04/12/2023]
Abstract
Congenital toxoplasmosis constitutes a major cause of pre- and postnatal complications. Fetal infection with Toxoplasma gondii influences development and can lead to microcephaly, encephalitis, and neurologic abnormalities. Systematic studies concerning the effects of neural progenitor cell infection with T. gondii are unavailable. Cortical intermediate progenitor cells cultivated as neurospheres obtained from E16.5 Swiss Webster mice were infected with T. gondii (ME49 strain) tachyzoites to mimic the developing mouse cerebral cortex in vitro. Infection was associated with decreased cell proliferation, detected by Ki-67 staining at 48 and 72 hours after infection in floating neurospheres, and reduced cellularity at 96 hours. Transient decreases in the expression of the neurogenesis-related transcription factors T-box brain protein 1, mouse atonal homolog protein 1, and hairy and enhancer of split protein 1 were found in infected cultures, while the level of transcription factor SOX-2 remained unaltered. Neurogenic potential, assessed in plated neurospheres, was impaired in infected cultures, as indicated by decreased late neuronal marker neurofilament heavy chain immunoreactivity. Infected cultures exhibited decreased overall migration rates at 48 and 120 hours. These findings indicate that T. gondii infection of neural progenitor cells may lead to reduced neurogenesis due to an imbalance in cell proliferation alongside an altered migratory profile. If translated to the in vivo situation, these data could explain, in part, cortical malformations in congenitally infected individuals.
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Affiliation(s)
- Luiza B Pires
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil; Laboratório de Neurobiologia Celular e Molecular, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maria C Peixoto-Rodrigues
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Jéssica F Eloi
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Cynthia M Cascabulho
- Laboratório de Inovações em Terapias, Ensino e Bioprodutos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Helene S Barbosa
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Marcelo F Santiago
- Laboratório de Neurobiologia Celular e Molecular, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Daniel Adesse
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil; Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida.
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4
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Licon MH, Giuliano CJ, Chan AW, Chakladar S, Eberhard JN, Shallberg LA, Chandrasekaran S, Waldman BS, Koshy AA, Hunter CA, Lourido S. A positive feedback loop controls Toxoplasma chronic differentiation. Nat Microbiol 2023; 8:889-904. [PMID: 37081202 PMCID: PMC10520893 DOI: 10.1038/s41564-023-01358-2] [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: 04/26/2022] [Accepted: 03/07/2023] [Indexed: 04/22/2023]
Abstract
Successful infection strategies must balance pathogen amplification and persistence. In the obligate intracellular parasite Toxoplasma gondii this is accomplished through differentiation into dedicated cyst-forming chronic stages that avoid clearance by the host immune system. The transcription factor BFD1 is both necessary and sufficient for stage conversion; however, its regulation is not understood. In this study we examine five factors that are transcriptionally activated by BFD1. One of these is a cytosolic RNA-binding protein of the CCCH-type zinc-finger family, which we name bradyzoite formation deficient 2 (BFD2). Parasites lacking BFD2 fail to induce BFD1 and are consequently unable to fully differentiate in culture or in mice. BFD2 interacts with the BFD1 transcript under stress, and deletion of BFD2 reduces BFD1 protein levels but not messenger RNA abundance. The reciprocal effects on BFD2 transcription and BFD1 translation outline a positive feedback loop that enforces the chronic-stage gene-expression programme. Thus, our findings help explain how parasites both initiate and commit to chronic differentiation. This work provides new mechanistic insight into the regulation of T. gondii persistence, and can be exploited in the design of strategies to prevent and treat these key reservoirs of human infection.
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Affiliation(s)
| | - Christopher J Giuliano
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alex W Chan
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sundeep Chakladar
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Julia N Eberhard
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Lindsey A Shallberg
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Benjamin S Waldman
- Whitehead Institute, Cambridge, MA, USA
- Department of Microbiology and Immunology, School of Medicine, Stanford University, Stanford, CA, USA
| | - Anita A Koshy
- BIO5 Institute, University of Arizona, Tucson, AZ, USA
- Department of Neurology, Department of Immunobiology, University of Arizona, Tucson, AZ, USA
| | - Christopher A Hunter
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sebastian Lourido
- Whitehead Institute, Cambridge, MA, USA.
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA, USA.
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5
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Kochanowsky JA, Chandrasekaran S, Sanchez JR, Thomas KK, Koshy AA. ROP16-mediated activation of STAT6 enhances cyst development of type III Toxoplasma gondii in neurons. PLoS Pathog 2023; 19:e1011347. [PMID: 37068104 PMCID: PMC10138205 DOI: 10.1371/journal.ppat.1011347] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 04/27/2023] [Accepted: 04/07/2023] [Indexed: 04/18/2023] Open
Abstract
Toxoplasma gondii establishes a long-lived latent infection in the central nervous system (CNS) of its hosts. Reactivation in immunocompromised individuals can lead to life threatening disease. Latent infection is driven by the ability of the parasite to convert from the acute-stage tachyzoite to the latent-stage bradyzoite which resides in long-lived intracellular cysts. While much work has focused on the parasitic factors that drive cyst development, the host factors that influence encystment are not well defined. Here we show that a polymorphic secreted parasite kinase (ROP16), that phosphorylates host cell proteins, mediates efficient encystment of T. gondii in a stress-induced model of encystment and primary neuronal cell cultures (PNCs) in a strain-specific manner. Using short-hairpin RNA (shRNA) knockdowns in human foreskin fibroblasts (HFFs) and PNCs from transgenic mice, we determined that ROP16's cyst enhancing abilities are mediated, in part, by phosphorylation-and therefore activation-of the host cell transcription factor STAT6. To test the role of STAT6 in vivo, we infected wild-type (WT) and STAT6KO mice, finding that, compared to WT mice, STAT6KO mice have a decrease in CNS cyst burden but not overall parasite burden or dissemination to the CNS. Finally, we found a similar ROP16-dependent encystment defect in human pluripotent stem cell-derived neurons. Together, these findings identify a host cell factor (STAT6) that T. gondii manipulates in a strain-specific manner to generate a favorable encystment environment.
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Affiliation(s)
- Joshua A. Kochanowsky
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | | | - Jacqueline R. Sanchez
- Postbaccalaureate Research Education Program, University of Arizona, Tucson, Arizona, United States of America
| | - Kaitlin K. Thomas
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Anita A. Koshy
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
- Department of Neurology, University of Arizona, Tucson, Arizona, United States of America
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6
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Biazzo M, Allegra M, Deidda G. Clostridioides difficile and neurological disorders: New perspectives. Front Neurosci 2022; 16:946601. [PMID: 36203814 PMCID: PMC9530032 DOI: 10.3389/fnins.2022.946601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/24/2022] [Indexed: 12/02/2022] Open
Abstract
Despite brain physiological functions or pathological dysfunctions relying on the activity of neuronal/non-neuronal populations, over the last decades a plethora of evidence unraveled the essential contribution of the microbial populations living and residing within the gut, called gut microbiota. The gut microbiota plays a role in brain (dys)functions, and it will become a promising valuable therapeutic target for several brain pathologies. In the present mini-review, after a brief overview of the role of gut microbiota in normal brain physiology and pathology, we focus on the role of the bacterium Clostridioides difficile, a pathogen responsible for recurrent and refractory infections, in people with neurological diseases, summarizing recent correlative and causative evidence in the scientific literature and highlighting the potential of microbiota-based strategies targeting this pathogen to ameliorate not only gastrointestinal but also the neurological symptoms.
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Affiliation(s)
- Manuele Biazzo
- The BioArte Limited, Life Sciences Park, San Gwann, Malta
- SienabioACTIVE, University of Siena, Siena, Italy
| | - Manuela Allegra
- Neuroscience Institute, National Research Council (IN-CNR), Padua, Italy
| | - Gabriele Deidda
- Department of Biomedical Sciences, University of Padua, Padua, Italy
- *Correspondence: Gabriele Deidda
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7
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Transcriptomic Analysis of the Effects of Chemokine Receptor CXCR3 Deficiency on Immune Responses in the Mouse Brain during Toxoplasma gondii Infection. Microorganisms 2021; 9:microorganisms9112340. [PMID: 34835465 PMCID: PMC8620038 DOI: 10.3390/microorganisms9112340] [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: 11/01/2021] [Accepted: 11/06/2021] [Indexed: 11/16/2022] Open
Abstract
The obligate intracellular parasite Toxoplasma gondii infects warm-blooded animals, including humans. We previously revealed through a whole-brain transcriptome analysis that infection with T. gondii in mice causes immune response-associated genes to be upregulated, for instance, chemokines and chemokine receptors such as CXC chemokine receptor 3 (CXCR3) and its ligand CXC chemokine ligand 10 (CXCL10). Here, we describe the effect of CXCR3 on responses against T. gondii infection in the mouse brain. In vivo assays using CXCR3-deficient mice showed that the absence of CXCR3 delayed the normal recovery of body weight and increased the brain parasite burden, suggesting that CXCR3 plays a role in the control of pathology in the brain, the site where chronic infection occurs. Therefore, to further analyze the function of CXCR3 in the brain, we profiled the gene expression patterns of primary astrocytes and microglia by RNA sequencing and subsequent analyses. CXCR3 deficiency impaired the normal upregulation of immune-related genes during T. gondii infection, in astrocytes and microglia alike. Collectively, our results suggest that the immune-related genes upregulated by CXCR3 perform a particular role in controlling pathology when the host is chronically infected with T. gondii in the brain.
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8
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Deidda G, Biazzo M. Gut and Brain: Investigating Physiological and Pathological Interactions Between Microbiota and Brain to Gain New Therapeutic Avenues for Brain Diseases. Front Neurosci 2021; 15:753915. [PMID: 34712115 PMCID: PMC8545893 DOI: 10.3389/fnins.2021.753915] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/16/2021] [Indexed: 12/12/2022] Open
Abstract
Brain physiological functions or pathological dysfunctions do surely depend on the activity of both neuronal and non-neuronal populations. Nevertheless, over the last decades, compelling and fast accumulating evidence showed that the brain is not alone. Indeed, the so-called "gut brain," composed of the microbial populations living in the gut, forms a symbiotic superorganism weighing as the human brain and strongly communicating with the latter via the gut-brain axis. The gut brain does exert a control on brain (dys)functions and it will eventually become a promising valuable therapeutic target for a number of brain pathologies. In the present review, we will first describe the role of gut microbiota in normal brain physiology from neurodevelopment till adulthood, and thereafter we will discuss evidence from the literature showing how gut microbiota alterations are a signature in a number of brain pathologies ranging from neurodevelopmental to neurodegenerative disorders, and how pre/probiotic supplement interventions aimed to correct the altered dysbiosis in pathological conditions may represent a valuable future therapeutic strategy.
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Affiliation(s)
- Gabriele Deidda
- The BioArte Limited, Life Sciences Park, San Gwann, Malta
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Manuele Biazzo
- The BioArte Limited, Life Sciences Park, San Gwann, Malta
- SienabioACTIVE, University of Siena, Siena, Italy
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9
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Mouveaux T, Roger E, Gueye A, Eysert F, Huot L, Grenier-Boley B, Lambert JC, Gissot M. Primary brain cell infection by Toxoplasma gondii reveals the extent and dynamics of parasite differentiation and its impact on neuron biology. Open Biol 2021; 11:210053. [PMID: 34610266 PMCID: PMC8492179 DOI: 10.1098/rsob.210053] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Toxoplasma gondii is a eukaryotic parasite that forms latent cysts in the brain of immunocompetent individuals. The latent parasite infection of the immune-privileged central nervous system is linked to most complications. With no drug currently available to eliminate the latent cysts in the brain of infected hosts, the consequences of neurons' long-term infection are unknown. It has long been known that T. gondii specifically differentiates into a latent form (bradyzoite) in neurons, but how the infected neuron responds to the infection remains to be elucidated. We have established a new in vitro model resulting in the production of mature bradyzoite cysts in brain cells. Using dual, host and parasite RNA-seq, we characterized the dynamics of differentiation of the parasite, revealing the involvement of key pathways in this process. Moreover, we identified how the infected brain cells responded to the parasite infection revealing the drastic changes that take place. We showed that neuronal-specific pathways are strongly affected, with synapse signalling being particularly affected, especially glutamatergic synapse signalling. The establishment of this new in vitro model allows investigating both the dynamics of parasite differentiation and the specific response of neurons to long-term infection by this parasite.
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Affiliation(s)
- Thomas Mouveaux
- U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, F-59000 Lille, France
| | - Emmanuel Roger
- U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, F-59000 Lille, France
| | - Alioune Gueye
- U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, F-59000 Lille, France
| | - Fanny Eysert
- U1167, University of Lille, Inserm, Institut Pasteur de Lille, F-59000 Lille, France
| | - Ludovic Huot
- U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, F-59000 Lille, France
| | | | - Jean-Charles Lambert
- U1167, University of Lille, Inserm, Institut Pasteur de Lille, F-59000 Lille, France
| | - Mathieu Gissot
- U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, F-59000 Lille, France
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10
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Valproic acid inhibits chronic Toxoplasma infection and associated brain inflammation in mice. Antimicrob Agents Chemother 2021; 65:e0100321. [PMID: 34339265 DOI: 10.1128/aac.01003-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Individuals infected with Toxoplasma gondii (T. gondii) are prone to psycho-behavioral disorders, most notably schizophrenia and bipolar. Valproic acid reportedly inhibited the proliferation of T. gondii tachyzoites in vitro. However, animals treated with the drug neither lived longer during acute infection nor had fewer brain cysts upon chronic infection. In this study, a quantitative real-time PCR (qPCR) method was applied to quantify copy numbers of BAG1 (a bradyzoite-specific protein), REP529 DNA (a repetitive DNA fragment of the parasite), and SAG1 (a highly expressed tachyzoite-specific surface protein) in brains of chronically infected mice treated by valproic acid. The treatment inhibited the infection and decreased BAG1, SAG1, and REP529 copy numbers in mice brains (P < 0.0001), comparable to Trimethoprim/Sulfamethoxazole (TMP/SMZ), the common medication for Toxoplasmosis treatment. Moreover, valproic acid decreased brain TNF-α expression (P < 0.0001), comparable to TMP/SMZ. Histological examination of mice brains showed a marked reduction in cyst establishment, perivascular infiltration of lymphocytes, and glial nodules to the same level as the TMP/SMZ group. Our results provide direct evidence for the efficacy of valproic acid, a mood-stabilizing and antipsychotic drug against chronic Toxoplasma infection. These results might help modulate therapeutic regimens for neuropsychiatric patients and design more effective anti-Toxoplasma drugs.
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11
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Matta SK, Rinkenberger N, Dunay IR, Sibley LD. Toxoplasma gondii infection and its implications within the central nervous system. Nat Rev Microbiol 2021; 19:467-480. [PMID: 33627834 DOI: 10.1038/s41579-021-00518-7] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2021] [Indexed: 01/31/2023]
Abstract
Toxoplasma gondii is a parasite that infects a wide range of animals and causes zoonotic infections in humans. Although it normally only results in mild illness in healthy individuals, toxoplasmosis is a common opportunistic infection with high mortality in individuals who are immunocompromised, most commonly due to reactivation of infection in the central nervous system. In the acute phase of infection, interferon-dependent immune responses control rapid parasite expansion and mitigate acute disease symptoms. However, after dissemination the parasite differentiates into semi-dormant cysts that form within muscle cells and neurons, where they persist for life in the infected host. Control of infection in the central nervous system, a compartment of immune privilege, relies on modified immune responses that aim to balance infection control while limiting potential damage due to inflammation. In response to the activation of interferon-mediated pathways, the parasite deploys an array of effector proteins to escape immune clearance and ensure latent survival. Although these pathways are best studied in the laboratory mouse, emerging evidence points to unique mechanisms of control in human toxoplasmosis. In this Review, we explore some of these recent findings that extend our understanding for proliferation, establishment and control of toxoplasmosis in humans.
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Affiliation(s)
- Sumit K Matta
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicholas Rinkenberger
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Ildiko R Dunay
- Institute of Inflammation and Neurodegeneration, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - L David Sibley
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
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The role of upstream open reading frames in translation regulation in the apicomplexan parasites Plasmodium falciparum and Toxoplasma gondii. Parasitology 2021; 148:1277-1287. [PMID: 34099078 PMCID: PMC8383288 DOI: 10.1017/s0031182021000937] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
During their complex life cycles, the Apicomplexan parasites Plasmodium falciparum and Toxoplasma gondii employ several layers of regulation of their gene expression. One such layer is mediated at the level of translation through upstream open reading frames (uORFs). As uORFs are found in the upstream regions of a majority of transcripts in both the parasites, it is essential that their roles in translational regulation be appreciated to a greater extent. This review provides a comprehensive summary of studies that show uORF-mediated gene regulation in these parasites and highlights examples of clinically and physiologically relevant genes, including var2csa in P. falciparum, and ApiAT1 in T. gondii, that exhibit uORF-mediated regulation. In addition to these examples, several studies that use bioinformatics, transcriptomics, proteomics and ribosome profiling also indicate the possibility of widespread translational regulation by uORFs. Further analysis of these genome-wide datasets, taking into account uORFs associated with each gene, will reveal novel genes involved in key biological pathways such as cell-cycle progression, stress-response and pathogenicity. The cumulative evidence from studies presented in this review suggests that uORFs will play crucial roles in regulating gene expression during clinical disease caused by these important human pathogens.
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Elsheikha HM, Marra CM, Zhu XQ. Epidemiology, Pathophysiology, Diagnosis, and Management of Cerebral Toxoplasmosis. Clin Microbiol Rev 2021; 34:e00115-19. [PMID: 33239310 PMCID: PMC7690944 DOI: 10.1128/cmr.00115-19] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Toxoplasma gondii is known to infect a considerable number of mammalian and avian species and a substantial proportion of the world's human population. The parasite has an impressive ability to disseminate within the host's body and employs various tactics to overcome the highly regulatory blood-brain barrier and reside in the brain. In healthy individuals, T. gondii infection is largely tolerated without any obvious ill effects. However, primary infection in immunosuppressed patients can result in acute cerebral or systemic disease, and reactivation of latent tissue cysts can lead to a deadly outcome. It is imperative that treatment of life-threatening toxoplasmic encephalitis is timely and effective. Several therapeutic and prophylactic regimens have been used in clinical practice. Current approaches can control infection caused by the invasive and highly proliferative tachyzoites but cannot eliminate the dormant tissue cysts. Adverse events and other limitations are associated with the standard pyrimethamine-based therapy, and effective vaccines are unavailable. In this review, the epidemiology, economic impact, pathophysiology, diagnosis, and management of cerebral toxoplasmosis are discussed, and critical areas for future research are highlighted.
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Affiliation(s)
- Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Loughborough, United Kingdom
| | - Christina M Marra
- Departments of Neurology and Medicine, University of Washington School of Medicine, Seattle, Washington, USA
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, People's Republic of China
- College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province, People's Republic of China
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14
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Shinjyo N, Hikosaka K, Kido Y, Yoshida H, Norose K. Toxoplasma Infection Induces Sustained Up-Regulation of Complement Factor B and C5a Receptor in the Mouse Brain via Microglial Activation: Implication for the Alternative Complement Pathway Activation and Anaphylatoxin Signaling in Cerebral Toxoplasmosis. Front Immunol 2021; 11:603924. [PMID: 33613523 PMCID: PMC7892429 DOI: 10.3389/fimmu.2020.603924] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/21/2020] [Indexed: 01/01/2023] Open
Abstract
Toxoplasma gondii is a neurotropic protozoan parasite, which is linked to neurological manifestations in immunocompromised individuals as well as severe neurodevelopmental sequelae in congenital toxoplasmosis. While the complement system is the first line of host defense that plays a significant role in the prevention of parasite dissemination, Toxoplasma artfully evades complement-mediated clearance via recruiting complement regulatory proteins to their surface. On the other hand, the details of Toxoplasma and the complement system interaction in the brain parenchyma remain elusive. In this study, infection-induced changes in the mRNA levels of complement components were analyzed by quantitative PCR using a murine Toxoplasma infection model in vivo and primary glial cells in vitro. In addition to the core components C3 and C1q, anaphylatoxin C3a and C5a receptors (C3aR and C5aR1), as well as alternative complement pathway components properdin (CFP) and factor B (CFB), were significantly upregulated 2 weeks after inoculation. Two months post-infection, CFB, C3, C3aR, and C5aR1 expression remained higher than in controls, while CFP upregulation was transient. Furthermore, Toxoplasma infection induced significant increase in CFP, CFB, C3, and C5aR1 in mixed glial culture, which was abrogated when microglial activation was inhibited by pre-treatment with minocycline. This study sheds new light on the roles for the complement system in the brain parenchyma during Toxoplasma infection, which may lead to the development of novel therapeutic approaches to Toxoplasma infection-induced neurological disorders.
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MESH Headings
- Animals
- Brain/immunology
- Brain/metabolism
- Brain/parasitology
- Cells, Cultured
- Complement Factor B/genetics
- Complement Factor B/metabolism
- Complement Pathway, Alternative
- Disease Models, Animal
- Host-Parasite Interactions
- Male
- Mice, Inbred C57BL
- Microglia/immunology
- Microglia/metabolism
- Microglia/parasitology
- Receptor, Anaphylatoxin C5a/genetics
- Receptor, Anaphylatoxin C5a/metabolism
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Signal Transduction
- Time Factors
- Toxoplasma/immunology
- Toxoplasma/pathogenicity
- Toxoplasmosis, Animal/genetics
- Toxoplasmosis, Animal/immunology
- Toxoplasmosis, Animal/metabolism
- Toxoplasmosis, Animal/parasitology
- Toxoplasmosis, Cerebral/genetics
- Toxoplasmosis, Cerebral/immunology
- Toxoplasmosis, Cerebral/metabolism
- Toxoplasmosis, Cerebral/parasitology
- Up-Regulation
- Mice
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Affiliation(s)
- Noriko Shinjyo
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
- Department of Parasitology & Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | - Kenji Hikosaka
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yasutoshi Kido
- Department of Parasitology & Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga, Japan
| | - Kazumi Norose
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
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15
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Oschwald A, Petry P, Kierdorf K, Erny D. CNS Macrophages and Infant Infections. Front Immunol 2020; 11:2123. [PMID: 33072074 PMCID: PMC7531029 DOI: 10.3389/fimmu.2020.02123] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/05/2020] [Indexed: 12/11/2022] Open
Abstract
The central nervous system (CNS) harbors its own immune system composed of microglia in the parenchyma and CNS-associated macrophages (CAMs) in the perivascular space, leptomeninges, dura mater, and choroid plexus. Recent advances in understanding the CNS resident immune cells gave new insights into development, maturation and function of its immune guard. Microglia and CAMs undergo essential steps of differentiation and maturation triggered by environmental factors as well as intrinsic transcriptional programs throughout embryonic and postnatal development. These shaping steps allow the macrophages to adapt to their specific physiological function as first line of defense of the CNS and its interfaces. During infancy, the CNS might be targeted by a plethora of different pathogens which can cause severe tissue damage with potentially long reaching defects. Therefore, an efficient immune response of infant CNS macrophages is required even at these early stages to clear the infections but may also lead to detrimental consequences for the developing CNS. Here, we highlight the recent knowledge of the infant CNS immune system during embryonic and postnatal infections and the consequences for the developing CNS.
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Affiliation(s)
- Alexander Oschwald
- Faculty of Medicine, Institute of Neuropathology, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Philippe Petry
- Faculty of Medicine, Institute of Neuropathology, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Katrin Kierdorf
- Faculty of Medicine, Institute of Neuropathology, University of Freiburg, Freiburg, Germany.,CIBBS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.,Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Daniel Erny
- Faculty of Medicine, Institute of Neuropathology, University of Freiburg, Freiburg, Germany
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16
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Kochanowsky JA, Koshy AA. A Single Transcription Factor Drives Toxoplasma gondii Differentiation. Cell 2020; 180:216-218. [PMID: 31978340 DOI: 10.1016/j.cell.2019.12.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Microbes that cause persistent infections (e.g., herpes viruses) do so by switching from fast-growing lytic states to slow-growing latent states. Waldman et al. have identified a single transcription factor that governs the switch between the lytic and latent forms of Toxoplasma gondii, a parasite that causes a persistent brain infection.
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Affiliation(s)
| | - Anita A Koshy
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA; Department of Neurology, University of Arizona, Tucson, Arizona, USA; Bio5 Institute, University of Arizona, Tucson, Arizona, USA.
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Marcos AC, Siqueira M, Alvarez-Rosa L, Cascabulho CM, Waghabi MC, Barbosa HS, Adesse D, Stipursky J. Toxoplasma gondii infection impairs radial glia differentiation and its potential to modulate brain microvascular endothelial cell function in the cerebral cortex. Microvasc Res 2020; 131:104024. [PMID: 32502488 DOI: 10.1016/j.mvr.2020.104024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 04/30/2020] [Accepted: 05/08/2020] [Indexed: 01/30/2023]
Abstract
Congenital toxoplasmosis is a parasitic disease that occurs due vertical transmission of the protozoan Toxoplasma gondii (T. gondii) during pregnancy. The parasite crosses the placental barrier and reaches the developing brain, infecting progenitor, glial, neuronal and vascular cell types. Although the role of Radial glia (RG) neural stem cells in the development of the brain vasculature has been recently investigated, the impact of T. gondii infection in these events is not yet understood. Herein, we studied the role of T. gondii infection on RG cell function and its interaction with endothelial cells. By infecting isolated RG cultures with T. gondii tachyzoites, we observed a cytotoxic effect with reduced numbers of RG populations together with decrease neuronal and oligodendrocyte progenitor populations. Conditioned medium (CM) from RG control cultures increased ZO-1 protein levels and organization on endothelial bEnd.3 cells membranes, which was impaired by CM from infected RG, accompanied by decreased trans-endothelial electrical resistance (TEER). ELISA assays revealed reduced levels of anti-inflammatory cytokine TGF-β1 in CM from T. gondii-infected RG cells. Treatment with recombinant TGF-β1 concomitantly with CM from infected RG cultures led to restoration of ZO-1 staining in bEnd.3 cells. Congenital infection in Swiss Webster mice led to abnormalities in the cortical microvasculature in comparison to uninfected embryos. Our results suggest that infection of RG cells by T. gondii negatively modulates cytokine secretion, which might contribute to endothelial loss of barrier properties, thus leading to impairment of neurovascular interaction establishment.
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Affiliation(s)
| | - Michele Siqueira
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil
| | - Liandra Alvarez-Rosa
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Brazil; Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil
| | - Cynthia M Cascabulho
- Laboratório de Inovação em Terapias, Ensino e Bioprodutos, Instituto Oswaldo Cruz, Fiocruz, Brazil
| | - Mariana C Waghabi
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fiocruz, Brazil
| | - Helene S Barbosa
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Brazil
| | - Daniel Adesse
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Brazil
| | - Joice Stipursky
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil.
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18
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El Mouhawass A, Hammoud A, Zoghbi M, Hallit S, Haddad C, El Haddad K, El Khoury S, Tannous J, Obeid S, Halabi MA, Mammari N. Relationship between Toxoplasma gondii seropositivity and schizophrenia in the Lebanese population: potential implication of genetic polymorphism of MMP-9. BMC Psychiatry 2020; 20:264. [PMID: 32460746 PMCID: PMC7254747 DOI: 10.1186/s12888-020-02683-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 05/18/2020] [Indexed: 02/17/2023] Open
Abstract
BACKGROUND Toxoplasma multiplication and its persistence into the brain cause a local neuroinflammatory reaction, resulting synthesis of neurotransmitters involved in neurological disorders, especially schizophrenia. The Matrix metallopeptidase 9 (MMP-9) protein can play a major role in this neuroinflammation. It can promote extravasation and migration of infected immune cells into the brain. The objectives of this study are to determine the possible association between schizophrenia and toxoplasmosis and highlight the existence of gene polymorphism encoding MMP-9 protein's in patients presented both schizophrenia and toxoplasmosis. METHODS A case-control study was conducted on 150 patients with schizophrenia (case group), and 150 healthy persons (control group). Groups were matched with age, gender, and place of residence. The survey was conducted using a questionnaire and a serological profile assay for specific IgG and IgM antibodies against T. gondii. Reverse transcription-polymerase chain reaction (RT-PCR) of gene polymorphism encoding MMP-9 was performed on 83 cases selected randomly. RESULTS Data show a significant association between toxoplasmosis (IgM+/IgG+ serological profile) and schizophrenia. Significant effects of raw meat consumption and contact with cats have been associated with the occurrence of schizophrenia. RT-PCR shows the presence of muted allele of MMP-9 gene in selected cases whose present T. gondii serological profile IgM+/IgG+ and IgM-/IgG+ respectively. CONCLUSION Toxoplasmosis may be one of the etiological causes of schizophrenia, and MMP-9 gene polymorphism could be involved in the occurrence mechanism of this pathology following Toxoplasma infection.
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Affiliation(s)
- Amata El Mouhawass
- Medical Laboratory Department, Holy Family University, Batroun, 5534 Lebanon
| | - Amale Hammoud
- grid.444439.aPublic Health Faculty, Jinan University, Tripoli, Lebanon
| | - Marouan Zoghbi
- Psychiatric Hospital of the Cross, Jal Eddib, 6096 Lebanon ,grid.42271.320000 0001 2149 479XFaculty of Medicine, Saint-Joseph University, Beirut, Lebanon
| | - Souheil Hallit
- Faculty of Medicine and Medical Sciences, Holy Spirit University of Kaslik (USEK), Jounieh, Lebanon. .,INSPECT-LB: Institut National de Santé Publique, Épidémiologie Clinique et Toxicologie, Beirut, Lebanon.
| | - Chadia Haddad
- Psychiatric Hospital of the Cross, Jal Eddib, 6096 Lebanon ,grid.9966.00000 0001 2165 4861INSERM, Univ. Limoges, CH Esquirol Limoges, IRD, U1094 Tropical Neuroepidemiology, Institute of Epidemiology and Tropical Neurology, GEIST, Limoges, France
| | - Kinda El Haddad
- Medical Laboratory Department, Holy Family University, Batroun, 5534 Lebanon
| | - Saydeh El Khoury
- Medical Laboratory Department, Holy Family University, Batroun, 5534 Lebanon
| | - Jennifer Tannous
- Medical Laboratory Department, Holy Family University, Batroun, 5534 Lebanon
| | - Sahar Obeid
- Psychiatric Hospital of the Cross, Jal Eddib, 6096 Lebanon ,INSPECT-LB: Institut National de Santé Publique, Épidémiologie Clinique et Toxicologie, Beirut, Lebanon ,grid.444434.70000 0001 2106 3658Faculty of Arts and Sciences, Holy Spirit University of Kaslik (USEK), Jounieh, Lebanon
| | | | - Nour Mammari
- Medical Laboratory Department, Holy Family University, Batroun, 5534 Lebanon
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19
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Wong ZS, Borrelli SLS, Coyne CC, Boyle JP. Cell type- and species-specific host responses to Toxoplasma gondii and its near relatives. Int J Parasitol 2020; 50:423-431. [PMID: 32407716 PMCID: PMC8281328 DOI: 10.1016/j.ijpara.2020.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/30/2020] [Accepted: 04/03/2020] [Indexed: 10/24/2022]
Abstract
Toxoplasma gondii is remarkably unique in its ability to successfully infect vertebrate hosts from multiple phyla and can successfully infect most cells within these organisms. The infection outcome in each of these species is determined by the complex interaction between parasite and host genotype. As techniques to quantify global changes in cell function become more readily available and precise, new data are coming to light about how (i) different host cell types respond to parasitic infection and (ii) different parasite species impact the host. Here we focus on recent studies comparing the response to intracellular parasitism by different cell types and insights into understanding host-parasite interactions from comparative studies on T. gondii and its close extant relatives.
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Affiliation(s)
- Zhee S Wong
- Department of Biological Sciences, Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| | - Sarah L Sokol Borrelli
- Department of Biological Sciences, Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| | - Carolyn C Coyne
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Jon P Boyle
- Department of Biological Sciences, Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, United States.
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20
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The Bradyzoite: A Key Developmental Stage for the Persistence and Pathogenesis of Toxoplasmosis. Pathogens 2020; 9:pathogens9030234. [PMID: 32245165 PMCID: PMC7157559 DOI: 10.3390/pathogens9030234] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/18/2020] [Accepted: 03/19/2020] [Indexed: 12/19/2022] Open
Abstract
Toxoplasma gondii is a ubiquitous parasitic protist found in a wide variety of hosts, including a large proportion of the human population. Beyond an acute phase which is generally self-limited in immunocompetent individuals, the ability of the parasite to persist as a dormant stage, called bradyzoite, is an important aspect of toxoplasmosis. Not only is this stage not eliminated by current treatments, but it can also reactivate in immunocompromised hosts, leading to a potentially fatal outcome. Yet, despite its critical role in the pathology, the bradyzoite stage is relatively understudied. One main explanation is that it is a considerably challenging model, which essentially has to be derived from in vivo sources. However, recent progress on genetic manipulation and in vitro differentiation models now offers interesting perspectives for tackling key biological questions related to this particularly important developmental stage.
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21
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Abstract
Toxoplasma gondii, a member of the Apicomplexa, is known for its ability to infect an impressive range of host species. It is a common human infection that causes significant morbidity in congenitally infected children and immunocompromised patients. This parasite can be transmitted by bradyzoites, a slowly replicating life stage found within intracellular tissue cysts, and oocysts, the sexual life cycle stage that develops in domestic cats and other Felidae. T. gondii bradyzoites retain the capacity to revert back to the quickly replicating tachyzoite life stage, and when the host is immune compromised unrestricted replication can lead to significant tissue destruction. Bradyzoites are refractory to currently available Toxoplasma treatments. Improving our understanding of bradyzoite biology is critical for the development of therapeutic strategies to eliminate latent infection. This chapter describes a commonly used protocol for the differentiation of T. gondii tachyzoites into bradyzoites using human foreskin fibroblast cultures and a CO2-limited alkaline cell media, which results in a high proportion of differentiated bradyzoites for further study. Also described are methods for purifying tissue cysts from chronically infected mouse brain using isopycnic centrifugation and a recently developed approach for measuring bradyzoite viability.
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22
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Barbosa JL, Béla SR, Ricci MF, Noviello MDLM, Cartelle CT, Pinheiro BV, Vitor RWDA, Arantes RME. Spontaneous T. gondii neuronal encystment induces structural neuritic network impairment associated with changes of tyrosine hydroxilase expression. Neurosci Lett 2019; 718:134721. [PMID: 31891758 DOI: 10.1016/j.neulet.2019.134721] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 12/19/2019] [Accepted: 12/21/2019] [Indexed: 01/08/2023]
Abstract
Two billion people are chronically infected with Toxoplasma gondii worldwide with unknown consequences. Important neurological diseases have been associated to the brain infection, making essential to understand the neurophysiological changes associated with the neuronal encystment. T. gondii may subvert neuronal functions modifying neurotransmitter concentration in chronically infected mice but the molecular mechanisms involved are still unclear. Parasites were observed inside neuronal cells in cultures from 24-192 hs. The rate of infection increased with time. Neurite density decreased affecting network functionality. Neuronal survival was affected and we detected the presence of cysts inside neuronal bodies and dilated portions of neurites in association with a relative increase of TH-positive neuritic area without noticeable changes in DA immunofluorescence pattern. These results advance our knowledge of the interaction between T. gondii and the neuronal network of the host.
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Affiliation(s)
- Joana Lobato Barbosa
- Department of Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Samantha Ribeiro Béla
- Department of Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil; Department of Biological Science, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Minas Gerais, Brazil
| | - Mayra Fernanda Ricci
- Department of Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Christiane Teixeira Cartelle
- Department of Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Breno Veloso Pinheiro
- Departament of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ricardo Wagner de Almeida Vitor
- Departament of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Rosa Maria Esteves Arantes
- Department of Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
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Portes JA, De Souza W. Development of an in vitro system to study the developmental stages of Toxoplasma gondii using a genetically modified strain expressing markers for tachyzoites and bradyzoites. Parasitol Res 2019; 118:3479-3489. [PMID: 31728720 DOI: 10.1007/s00436-019-06493-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 09/30/2019] [Indexed: 10/25/2022]
Abstract
Toxoplasma gondii, the agent of toxoplasmosis, is an intracellular parasite that can infect a wide range of vertebrate hosts. Toxoplasmosis causes severe damage to immunocompromised hosts and its treatment is mainly based on the combination of pyrimethamine and sulfadiazine, which causes relevant side effects primarily observed in AIDS patients, including bone marrow suppression and hematological toxicity (pyrimethamine) and/or hypersensitivity and allergic skin reactions (sulfadiazine). Thus, it is important to investigate new compounds against T. gondii, particularly those that may act on bradyzoites, which are present in cysts during the chronic disease phase. We propose an in vitro model to simultaneously study new candidate compounds against the two main causative stages of Toxoplasma infection in humans, using the EGS-DC strain that was modified from a type I/III strain (EGS), isolated from a case of human congenital toxoplasmosis in Brazil and engineered to express markers for both stages of development. One feature of this strain is that it presents tachyzoite and bradyzoite in the same culture system and in the same host cell under normal culture conditions. Additionally, this strain presents stage-specific fluorescent protein expression, allowing for easy identification of both stages, thus making this strain useful in different studies. HFF cells were infected and after 4 and 7 days post infection the cells were treated with 10 μM of pyrimethamine or atovaquone, for 48 or 72 h. We used high-throughput screening to quantify the extent of parasite infection. Despite a reduction in tachyzoite infection caused by both treatments, the atovaquone treatment reduced the bradyzoite infection while the pyrimethamine one increased it. Ultrastructural analysis showed that after treatment with both drugs, parasites displayed altered mitochondria. Fluorescence microscopy of cells labeled with MitoTracker CMXRos showed that the cysts present inside the cells lost their mitochondrial membrane potential. Our results indicate that this experimental model is adequate to simultaneously analyze new active compounds against tachyzoite and bradyzoite forms.
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Affiliation(s)
- J A Portes
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, UFRJ, Av. Carlos Chagas Filho 373, Ilha do Fundão, Rio de Janeiro, RJ, Brazil.,Centro de Ciências da Saúde-UFRJ, Av. Carlos Chagas Filho 373, Ilha do Fundão, Rio de Janeiro, RJ, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagens, UFRJ, Av. Carlos Chagas Filho s/n, Ilha do Fundão, Rio de Janeiro, RJ, Brazil
| | - W De Souza
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, UFRJ, Av. Carlos Chagas Filho 373, Ilha do Fundão, Rio de Janeiro, RJ, Brazil. .,Centro de Ciências da Saúde-UFRJ, Av. Carlos Chagas Filho 373, Ilha do Fundão, Rio de Janeiro, RJ, Brazil. .,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagens, UFRJ, Av. Carlos Chagas Filho s/n, Ilha do Fundão, Rio de Janeiro, RJ, Brazil.
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24
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Figarella K, Wolburg H, Garaschuk O, Duszenko M. Microglia in neuropathology caused by protozoan parasites. Biol Rev Camb Philos Soc 2019; 95:333-349. [PMID: 31682077 DOI: 10.1111/brv.12566] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 10/04/2019] [Accepted: 10/07/2019] [Indexed: 12/31/2022]
Abstract
Involvement of the central nervous system (CNS) is the most severe consequence of some parasitic infections. Protozoal infections comprise a group of diseases that together affect billions of people worldwide and, according to the World Health Organization, are responsible for more than 500000 deaths annually. They include African and American trypanosomiasis, leishmaniasis, malaria, toxoplasmosis, and amoebiasis. Mechanisms underlying invasion of the brain parenchyma by protozoa are not well understood and may depend on parasite nature: a vascular invasion route is most common. Immunosuppression favors parasite invasion into the CNS and therefore the host immune response plays a pivotal role in the development of a neuropathology in these infectious diseases. In the brain, microglia are the resident immune cells active in defense against pathogens that target the CNS. Beside their direct role in innate immunity, they also play a principal role in coordinating the trafficking and recruitment of other immune cells from the periphery to the CNS. Despite their evident involvement in the neuropathology of protozoan infections, little attention has given to microglia-parasite interactions. This review describes the most prominent features of microglial cells and protozoan parasites and summarizes the most recent information regarding the reaction of microglial cells to parasitic infections. We highlight the involvement of the periphery-brain axis and emphasize possible scenarios for microglia-parasite interactions.
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Affiliation(s)
- Katherine Figarella
- Institute of Physiology, Department of Neurophysiology, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Hartwig Wolburg
- Institute of Pathology and Neuropathology, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Olga Garaschuk
- Institute of Physiology, Department of Neurophysiology, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Michael Duszenko
- Institute of Physiology, Department of Neurophysiology, Eberhard Karls University of Tübingen, Tübingen, Germany
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Kobayashi K, Umeda K, Ihara F, Tanaka S, Yamagishi J, Suzuki Y, Nishikawa Y. Transcriptome analysis of the effect of C-C chemokine receptor 5 deficiency on cell response to Toxoplasma gondii in brain cells. BMC Genomics 2019; 20:705. [PMID: 31506064 PMCID: PMC6737708 DOI: 10.1186/s12864-019-6076-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 09/04/2019] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Infection with Toxoplasma gondii is thought to damage the brain and be a risk factor for neurological and psychotic disorders. The immune response-participating chemokine system has recently been considered vital for brain cell signaling and neural functioning. Here, we investigated the effect of the deficiency of C-C chemokine receptor 5 (CCR5), which is previously reported to be associated with T. gondii infection, on gene expression in the brain during T. gondii infection and the relationship between CCR5 and the inflammatory response against T. gondii infection in the brain. RESULTS We performed a genome-wide comprehensive analysis of brain cells from wild-type and CCR5-deficient mice. Mouse primary brain cells infected with T. gondii were subjected to RNA sequencing. The expression levels of some genes, especially in astrocytes and microglia, were altered by CCR5-deficiency during T. gondii infection, and the gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis revealed an enhanced immune response in the brain cells. The expression levels of genes which were highly differentially expressed in vitro were also investigated in the mouse brains during the T. gondii infections. Among the genes tested, only Saa3 (serum amyloid A3) showed partly CCR5-dependent upregulation during the acute infection phase. However, analysis of the subacute phase showed that in addition to Saa3, Hmox1 may also contribute to the protection and/or pathology partly via the CCR5 pathway. CONCLUSIONS Our results indicate that CCR5 is involved in T. gondii infection in the brain where it contributes to inflammatory responses and parasite elimination. We suggest that the inflammatory response by glial cells through CCR5 might be associated with neurological injury during T. gondii infection to some extent.
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Affiliation(s)
- Kaoru Kobayashi
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
| | - Kousuke Umeda
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
| | - Fumiaki Ihara
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
| | - Sachi Tanaka
- Division of Animal Science, Department of Agricultural and Life Sciences, Faculty of Agriculture, Shinshu University, Minamiminowa, Nagano, Japan
| | - Junya Yamagishi
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Yutaka Suzuki
- Graduate School of Frontier Science, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Yoshifumi Nishikawa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan.
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26
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Bhandage AK, Kanatani S, Barragan A. Toxoplasma-Induced Hypermigration of Primary Cortical Microglia Implicates GABAergic Signaling. Front Cell Infect Microbiol 2019; 9:73. [PMID: 30949457 PMCID: PMC6436526 DOI: 10.3389/fcimb.2019.00073] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 03/05/2019] [Indexed: 11/30/2022] Open
Abstract
Toxoplasma gondii is a widespread obligate intracellular parasite that causes chronic infection and life-threatening acute infection in the central nervous system. Previous work identified Toxoplasma-infected microglia and astrocytes during reactivated infections in mice, indicating an implication of glial cells in acute toxoplasmic encephalitis. However, the mechanisms leading to the spread of Toxoplasma in the brain parenchyma remain unknown. Here, we report that, shortly after invasion by T. gondii tachyzoites, parasitized microglia, but not parasitized astrocytes, undergo rapid morphological changes and exhibit dramatically enhanced migration in 2-dimensional and 3-dimensional matrix confinements. Interestingly, primary microglia secreted the neurotransmitter γ-aminobutyric acid (GABA) in the supernatant as a consequence of T. gondii infection but not upon stimulation with LPS or heat-inactivated T. gondii. Further, microglia transcriptionally expressed components of the GABAergic machinery, including GABA-A receptor subunits, regulatory molecules and voltage-dependent calcium channels (VDCCs). Further, their transcriptional expression was modulated by challenge with T. gondii. Transcriptional analysis indicated that GABA was synthesized via both, the conventional pathway (glutamate decarboxylases GAD65 and GAD67) and a more recently characterized alternative pathway (aldehyde dehydrogenases ALDH2 and ALDH1a1). Pharmacological inhibitors targeting GABA synthesis, GABA-A receptors, GABA-A regulators and VDCC signaling inhibited Toxoplasma-induced hypermotility of microglia. Altogether, we show that primary microglia express a GABAergic machinery and that T. gondii induces hypermigration of microglia in a GABA-dependent fashion. We hypothesize that migratory activation of parasitized microglia by Toxoplasma may promote parasite dissemination in the brain parenchyma.
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Affiliation(s)
| | | | - Antonio Barragan
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
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27
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Schlüter D, Barragan A. Advances and Challenges in Understanding Cerebral Toxoplasmosis. Front Immunol 2019; 10:242. [PMID: 30873157 PMCID: PMC6401564 DOI: 10.3389/fimmu.2019.00242] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 01/28/2019] [Indexed: 11/22/2022] Open
Abstract
Toxoplasma gondii is a widespread parasitic pathogen that infects over one third of the global human population. The parasite invades and chronically persists in the central nervous system (CNS) of the infected host. Parasite spread and persistence is intimately linked to an ensuing immune response, which does not only limit parasite-induced damage but also may facilitate dissemination and induce parasite-associated immunopathology. Here, we discuss various aspects of toxoplasmosis where knowledge is scarce or controversial and, the recent advances in the understanding of the delicate interplay of T. gondii with the immune system in experimental and clinical settings. This includes mechanisms for parasite passage from the circulation into the brain parenchyma across the blood-brain barrier during primary acute infection. Later, as chronic latent infection sets in with control of the parasite in the brain parenchyma, the roles of the inflammatory response and of immune cell responses in this phase of the disease are discussed. Additionally, the function of brain resident cell populations is delineated, i.e., how neurons, astrocytes and microglia serve both as target cells for the parasite but also actively contribute to the immune response. As the infection can reactivate in the CNS of immune-compromised individuals, we bring up the immunopathogenesis of reactivated toxoplasmosis, including the special case of congenital CNS manifestations. The relevance, advantages and limitations of rodent infection models for the understanding of human cerebral toxoplasmosis are discussed. Finally, this review pinpoints questions that may represent challenges to experimental and clinical science with respect to improved diagnostics, pharmacological treatments and immunotherapies.
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Affiliation(s)
- Dirk Schlüter
- Hannover Medical School, Institute of Medical Microbiology and Hospital Epidemiology, Hannover, Germany
| | - Antonio Barragan
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
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28
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Bottari NB, Pillat MM, Schetinger MRC, Reichert KP, Machado V, Assmann CE, Ulrich H, Dutra A, Morsch VM, Vidal T, Da Cruz IBM, Melazzo C, Da Silva AS. Resveratrol-mediated reversal of changes in purinergic signaling and immune response induced by Toxoplasma gondii infection of neural progenitor cells. Purinergic Signal 2018; 15:77-84. [PMID: 30535987 DOI: 10.1007/s11302-018-9634-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 11/07/2018] [Indexed: 02/06/2023] Open
Abstract
The effects of Toxoplasma gondii during embryonic development have not been explored despite the predilection of this parasite for neurons and glial cells. Here, we investigated the activation of the purinergic system and proinflammatory responses during congenital infection by T. gondii. Moreover, neuroprotective and neuromodulatory properties of resveratrol (RSV), a polyphenolic natural compound, were studied in infected neuronal progenitor cells (NPCs). For this study, NPCs were isolated from the telencephalon of infected mouse embryos and subjected to neurosphere culture in the presence of EGF and FGF2. ATP hydrolysis and adenosine deamination by adenosine deaminase activity were altered in conditions of T. gondii infection. P2X7 and adenosine A2A receptor expression rates were augmented in infected NPCs together with an increase of proinflammatory (INF-γ and TNF-α) and anti-inflammatory (IL-10) cytokine gene expression. Our results confirm that RSV counteracted T. gondii-promoted effects on enzymes hydrolyzing extracellular nucleotides and nucleosides and also upregulated P2X7 and A2A receptor expression and activity, modulating INF-γ, TNF-α, and IL-10 cytokine production, which plays an integral role in the immune response against T. gondii.
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Affiliation(s)
- Nathieli B Bottari
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil. .,Department of Animal Science, University of Santa Catarina State, 680 D, Rua Beloni Trombeta Zanin, Chapecó, SC, 89815-630, Brazil.
| | - Micheli M Pillat
- Department of Biochemistry, Institute of Chemistry, Universidade de São Paulo (USP), São Paulo, SP, Brazil.
| | - Maria R C Schetinger
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Karine P Reichert
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Vanessa Machado
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Charles E Assmann
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Anielen Dutra
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Vera M Morsch
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Taís Vidal
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Ivana B M Da Cruz
- Graduate Program in Pharmacology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Cinthia Melazzo
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Aleksandro Schafer Da Silva
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil. .,Department of Animal Science, University of Santa Catarina State, 680 D, Rua Beloni Trombeta Zanin, Chapecó, SC, 89815-630, Brazil. .,Graduate Program in Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil.
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29
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Tyebji S, Seizova S, Hannan AJ, Tonkin CJ. Toxoplasmosis: A pathway to neuropsychiatric disorders. Neurosci Biobehav Rev 2018; 96:72-92. [PMID: 30476506 DOI: 10.1016/j.neubiorev.2018.11.012] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 10/23/2018] [Accepted: 11/22/2018] [Indexed: 12/24/2022]
Abstract
Toxoplasma gondii is an obligate intracellular parasite that resides, in a latent form, in the human central nervous system. Infection with Toxoplasma drastically alters the behaviour of rodents and is associated with the incidence of specific neuropsychiatric conditions in humans. But the question remains: how does this pervasive human pathogen alter behaviour of the mammalian host? This fundamental question is receiving increasing attention as it has far reaching public health implications for a parasite that is very common in human populations. Our current understanding centres on neuronal changes that are elicited directly by this intracellular parasite versus indirect changes that occur due to activation of the immune system within the CNS, or a combination of both. In this review, we explore the interactions between Toxoplasma and its host, the proposed mechanisms and consequences on neuronal function and mental health, and discuss Toxoplasma infection as a public health issue.
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Affiliation(s)
- Shiraz Tyebji
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Australia; Department of Medical Biology, The University of Melbourne, Melbourne, 3052, Australia; Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, 3052, Victoria, Australia.
| | - Simona Seizova
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Australia; Department of Medical Biology, The University of Melbourne, Melbourne, 3052, Australia.
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, 3052, Victoria, Australia; Department of Anatomy and Neuroscience, University of Melbourne, Parkville, 3052, Victoria, Australia.
| | - Christopher J Tonkin
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Australia; Department of Medical Biology, The University of Melbourne, Melbourne, 3052, Australia.
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30
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Bottari NB, Schetinger MRC, Pillat MM, Palma TV, Ulrich H, Alves MS, Morsch VM, Melazzo C, de Barros LD, Garcia JL, Da Silva AS. Resveratrol as a Therapy to Restore Neurogliogenesis of Neural Progenitor Cells Infected by Toxoplasma gondii. Mol Neurobiol 2018; 56:2328-2338. [PMID: 30027338 DOI: 10.1007/s12035-018-1180-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 06/06/2018] [Indexed: 11/25/2022]
Abstract
The intracellular protozoan Toxoplasma gondii may cause congenital toxoplasmosis and serious brain damage in fetus. However, the underlying mechanism of neuropathogenesis in brain toxoplasmosis remains unclear. For this study, neural progenitor cells (NPCs) were obtained from embryo telencephalons (embryonic day 13) and induced to proliferation in the presence of growth factors (GFs). For gathering insights into the biological effects of resveratrol (RSV) on neurogenesis, this study aimed to investigate effects of RSV concentrations (0.1 to 100 μM) on proliferation, migration and differentiation of NPCs infected by T. gondii. T. gondii infection increased the presence of cells in Sub G1 phase, reducing the global frequency of undifferentiated cells in S and G2/M phases of cell cycle and reduced cell viability/mithochondrial activity of infected NPCs. Moreover T. gondii stimulated neural migration and gliogenesis during neutral differentation. However, the treatment with RSV stimulated cell proliferation, restored cellular viability of infected NPCs and exerted an inhibitory effect on gliogenesis of infected NPCs favorecing neuronal maturation during toxoplasmosis infection. Thus, we have successfully to demonstrated that RSV is promising as therapeutic for congenital toxoplasmosis.
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Affiliation(s)
- Nathieli B Bottari
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Avenida Roraima, n°1000, Camobi District, Zip Code, Santa Maria, 97105900, Brazil
| | - Maria Rosa C Schetinger
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Avenida Roraima, n°1000, Camobi District, Zip Code, Santa Maria, 97105900, Brazil
| | - Micheli M Pillat
- Department of Biochemistry, Institute of Chemistry, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Thais V Palma
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Avenida Roraima, n°1000, Camobi District, Zip Code, Santa Maria, 97105900, Brazil
| | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Mariana S Alves
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Avenida Roraima, n°1000, Camobi District, Zip Code, Santa Maria, 97105900, Brazil
| | - Vera M Morsch
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Avenida Roraima, n°1000, Camobi District, Zip Code, Santa Maria, 97105900, Brazil
| | - Cinthia Melazzo
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Avenida Roraima, n°1000, Camobi District, Zip Code, Santa Maria, 97105900, Brazil
| | - Luiz Daniel de Barros
- Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina (UEL), Londrina, Paraná, PR, Brazil
| | - João Luis Garcia
- Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina (UEL), Londrina, Paraná, PR, Brazil
| | - Aleksandro Schafer Da Silva
- Graduate Program in Toxicological Biochemical and Department of Biochemistry and Molecular Biology, Universidade Federal de Santa Maria (UFSM), Avenida Roraima, n°1000, Camobi District, Zip Code, Santa Maria, 97105900, Brazil.
- Graduate Program in Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil.
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31
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Umeda K, Tanaka S, Ihara F, Yamagishi J, Suzuki Y, Nishikawa Y. Transcriptional profiling of Toll-like receptor 2-deficient primary murine brain cells during Toxoplasma gondii infection. PLoS One 2017; 12:e0187703. [PMID: 29136637 PMCID: PMC5685635 DOI: 10.1371/journal.pone.0187703] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/24/2017] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Toxoplasma gondii is capable of persisting in the brain, although it is efficiently eliminated by cellular immune responses in most other sites. While Toll-like receptor 2 (TLR2) reportedly plays important roles in protective immunity against the parasite, the relationship between neurological disorders induced by T. gondii infection and TLR2 function in the brain remains controversial with many unknowns. In this study, primary cultured astrocytes, microglia, neurons, and peritoneal macrophages obtained from wild-type and TLR2-deficient mice were exposed to T. gondii tachyzoites. To characterize TLR2-dependent functional pathways activated in response to T. gondii infection, gene expression of different cell types was profiled by RNA sequencing. RESULTS During T. gondii infection, a total of 611, 777, 385, and 1105 genes were upregulated in astrocytes, microglia, neurons, and macrophages, respectively, while 163, 1207, 158, and 1274 genes were downregulated, respectively, in a TLR2-dependent manner. Overrepresented Gene Ontology (GO) terms for TLR2-dependently upregulated genes were associated with immune and stress responses in astrocytes, immune responses and developmental processes in microglia, metabolic processes and immune responses in neurons, and metabolic processes and gene expression in macrophages. Overrepresented GO terms for downregulated genes included ion transport and behavior in astrocytes, cell cycle and cell division in microglia, metabolic processes in neurons, and response to stimulus, signaling and cell motility in macrophages. CONCLUSIONS To our knowledge, this is the first transcriptomic study of TLR2 function across different cell types during T. gondii infection. Results of RNA-sequencing demonstrated roles for TLR2 varied by cell type during T. gondii infection. Our findings facilitate understanding of the detailed relationship between TLR2 and T. gondii infection, and elucidate mechanisms underlying neurological changes during infection.
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Affiliation(s)
- Kousuke Umeda
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
| | - Sachi Tanaka
- Division of Animal Science, Department of Agricultural and Life Sciences, Faculty of Agriculture, Shinshu University, Minamiminowa, Nagano, Japan
| | - Fumiaki Ihara
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
| | - Junya Yamagishi
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Yutaka Suzuki
- Graduate School of Frontier Science, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Yoshifumi Nishikawa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
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32
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Swierzy IJ, Händel U, Kaever A, Jarek M, Scharfe M, Schlüter D, Lüder CGK. Divergent co-transcriptomes of different host cells infected with Toxoplasma gondii reveal cell type-specific host-parasite interactions. Sci Rep 2017; 7:7229. [PMID: 28775382 PMCID: PMC5543063 DOI: 10.1038/s41598-017-07838-w] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 06/30/2017] [Indexed: 02/06/2023] Open
Abstract
The apicomplexan parasite Toxoplasma gondii infects various cell types in avian and mammalian hosts including humans. Infection of immunocompetent hosts is mostly asymptomatic or benign, but leads to development of largely dormant bradyzoites that persist predominantly within neurons and muscle cells. Here we have analyzed the impact of the host cell type on the co-transcriptomes of host and parasite using high-throughput RNA sequencing. Murine cortical neurons and astrocytes, skeletal muscle cells (SkMCs) and fibroblasts differed by more than 16,200 differentially expressed genes (DEGs) before and after infection with T. gondii. However, only a few hundred of them were regulated by infection and these largely diverged in neurons, SkMCs, astrocytes and fibroblasts indicating host cell type-specific transcriptional responses after infection. The heterogeneous transcriptomes of host cells before and during infection coincided with ~5,400 DEGs in T. gondii residing in different cell types. Finally, we identified gene clusters in both T. gondii and its host, which correlated with the predominant parasite persistence in neurons or SkMCs as compared to astrocytes or fibroblasts. Thus, heterogeneous expression profiles of different host cell types and the parasites’ ability to adapting to them may govern the parasite-host cell interaction during toxoplasmosis.
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Affiliation(s)
- Izabela J Swierzy
- Institute for Medical Microbiology, University Medical Center, Georg-August-University, 37075, Göttingen, Germany
| | - Ulrike Händel
- Institute of Medical Microbiology, Infection Control and Prevention, Otto-von-Guericke-University, 39120, Magdeburg, Germany
| | - Alexander Kaever
- Institute of Microbiology and Genetics, Department of Bioinformatics, Georg-August-University, 37077, Göttingen, Germany
| | - Michael Jarek
- Genome Analytics, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany
| | - Maren Scharfe
- Genome Analytics, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany
| | - Dirk Schlüter
- Institute of Medical Microbiology, Infection Control and Prevention, Otto-von-Guericke-University, 39120, Magdeburg, Germany.,Organ-Specific Immune Regulation, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany
| | - Carsten G K Lüder
- Institute for Medical Microbiology, University Medical Center, Georg-August-University, 37075, Göttingen, Germany.
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33
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Wohlfert EA, Blader IJ, Wilson EH. Brains and Brawn: Toxoplasma Infections of the Central Nervous System and Skeletal Muscle. Trends Parasitol 2017; 33:519-531. [PMID: 28483381 PMCID: PMC5549945 DOI: 10.1016/j.pt.2017.04.001] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/29/2017] [Accepted: 04/08/2017] [Indexed: 02/06/2023]
Abstract
Toxoplasma gondii is a widespread parasitic pathogen that infects over a third of the world's population. Following an acute infection, the parasite can persist within its mammalian host as intraneuronal or intramuscular cysts. Cysts will occasionally reactivate, and - depending on the host's immune status and site of reactivation - encephalitis or myositis can develop. Because these diseases have high levels of morbidity and can be lethal, it is important to understand how Toxoplasma traffics to these tissues, how the immune response controls parasite burden and contributes to tissue damage, and what mechanisms underlie neurological and muscular pathologies that toxoplasmosis patients present with. This review aims to summarize recent important developments addressing these critical topics.
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Affiliation(s)
- Elizabeth A Wohlfert
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, NY, USA.
| | - Ira J Blader
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, NY, USA.
| | - Emma H Wilson
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, USA.
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34
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Hegazi AG, Al Guthami FM, Al Gethami AF, El Fadaly HA. Beneficial Effects of Capparis Spinosa Honey on the Immune Response of Rats Infected with Toxoplasma Gundii. J Pharmacopuncture 2017; 20:112-118. [PMID: 30087788 PMCID: PMC5532470 DOI: 10.3831/kpi.2017.20.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 05/30/2017] [Accepted: 06/13/2017] [Indexed: 12/15/2022] Open
Abstract
Objectives The Toxoplasma gondii (T. gondii) is an intracellular opportunistic protozoan parasite that infects approximately one-third of the human population worldwide. Honey has long been used for treatment of many diseases in folk medicine. Honey has exhibited significant anthelmintic, nematicidal and anti-protozoal activities.This study was conducted to investigate the immunological patterns in rats infected with T. gondii who were treated orally with supplemented 15% Capparis spinosa honey (Saudi Arabia) for a period of 28 days. Methods Immunoglobulin M, immunoglobulin G, and cytokines were detected by using enzyme-linked immunosorbent assays (ELISAs). In addition, the mortality and the morbidity rates were assessed. Results Oral administration of Capparis spinosa honey as a natural food additive was experimentally shown to increase the antibody titer; furthermore, compared with the rats in the control group, the levels of the sera cytokines (IFN-γ, IL-1 and IL-6) were consistently higher at day 7 post-infection in the infected rats treated with oral supplements of Capparis spinosa honey. Conclusion Orally administered supplements of Capparis spinosa honey increased both the antibody titer and the cytokines (IFN-γ, IL-1 and IL-6) levels in rats infected with T. gondii.
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Abstract
The unicellular parasite Toxoplasma gondii infects warm-blooded animals and humans, and it is highly prevalent throughout the world. Infection of immunocompetent hosts is usually asymptomatic or benign but leads to long-term parasite persistence mainly within neural and muscular tissues. The transition from acute primary infection towards chronic toxoplasmosis is accompanied by a developmental switch from fast replicating and metabolically highly active tachyzoites to slow replicating and largely dormant bradyzoites within tissue cysts. Such developmental differentiation is critical for T. gondii in order to complete its life cycle and for pathogenesis. Herein, we summarize accumulating evidence indicating a major impact of the host cell physiology on stage conversion between the tachyzoite and the bradyzoite stage of the parasite. Withdrawal from cell cycle progression, proinflammatory responses, reduced availability of nutrients and extracellular adenosine can indeed induce tachyzoite-to-bradyzoite differentiation and tissue cyst formation. In contrast, high glycolytic activity as indicated by increased lactate secretion can inhibit bradyzoite formation. These examples argue for the intriguing possibility that after dissemination within its host, T. gondii can sense its cellular microenvironment to initiate the developmental program towards the bradyzoite stage in distinct cells. This may also explain the predominant localization of T. gondii in neural and muscular tissues during chronic toxoplasmosis.
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Affiliation(s)
- Carsten G K Lüder
- Institute for Medical Microbiology, University Medical Center Goettingen, Goettingen, Germany
| | - Taibur Rahman
- Institute for Medical Microbiology, University Medical Center Goettingen, Goettingen, Germany
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Toxoplasma gondii: One Organism, Multiple Models. Trends Parasitol 2016; 33:113-127. [PMID: 27988095 DOI: 10.1016/j.pt.2016.11.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 11/15/2016] [Accepted: 11/18/2016] [Indexed: 12/13/2022]
Abstract
Toxoplasma gondii is an intensely studied protozoan parasite. It is also used as a model organism to research additional clinically relevant human and veterinary parasites due to ease of in vitro culture and genetic manipulation. Recently, it has been developed as a model of inflammatory bowel disease, due to their similar pathologies. However, researchers vary widely in how they use T. gondii, which makes study comparisons and interpretation difficult. The aim of this review is to provide researchers with a tool to: (i) determine the appropriateness of the different T. gondii models to their research, (ii) interpret results from the wide range of study conditions, and (iii) consider new advances in technology which could improve or refine their experimental setup.
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Ene L, Marcotte TD, Umlauf A, Grancea C, Temereanca A, Bharti A, Achim CL, Letendre S, Ruta SM. Latent toxoplasmosis is associated with neurocognitive impairment in young adults with and without chronic HIV infection. J Neuroimmunol 2016; 299:1-7. [PMID: 27725106 DOI: 10.1016/j.jneuroim.2016.08.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 07/30/2016] [Accepted: 08/02/2016] [Indexed: 12/11/2022]
Abstract
We evaluated the impact of latent toxoplasmosis (LT) on neurocognitive (NC) and neurobehavioural functioning in young adults with and without chronic HIV infection, using a standardised NC test battery, self-reported Beck Depression Inventory, Frontal System Behavior Scale, MINI-International Neuropsychiatric Interview and risk-assessment battery. 194 young adults (median age 24years, 48.2% males) with chronic HIV infection (HIV+) since childhood and 51 HIV seronegative (HIV-) participants were included. HIV+ individuals had good current immunological status (median CD4: 479 cells/μl) despite a low CD4 nadir (median: 93 cells/μl). LT (positive anti-Toxoplasma IgG antibodies) was present in one third of participants. The impairment rates in the HIV- with and without Toxo were not significantly different (p=0.17). However, we observed an increasing trend (p<0.001) in impairment rates with HIV and LT status: HIV-/LT- (6.1%); HIV-/LT+ (22%), HIV+/LT- (31%), HIV+/LT+ (49%). In a multivariable analysis using the entire study group there were main effects on cognition for HIV and also for LT. Within the HIV+ group LT was associated with worse performance globally (p=0.006), in memory (p=0.009), speed of information processing (p=0.01), verbal (p=0.02) and learning (p=0.02) domains. LT was not associated with depressive symptoms, frontal systems dysfunction or risk behaviors in any of the groups. HIV participants with lower Toxoplasma antibody concentration had worse NC performance, with higher GDS values (p=0.03) and worse learning (p=0.002), memory (p=0.006), speed of information processing (p=0.01) T scores. Latent Toxoplasmosis may contribute to NC impairment in young adults, including those with and without chronic HIV infection.
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Affiliation(s)
- L Ene
- "Dr. Victor Babes" Hospital for Infectious and Tropical Diseases, Bucharest, Romania.
| | - T D Marcotte
- University of California San Diego, La Jolla, CA, USA
| | - A Umlauf
- University of California San Diego, La Jolla, CA, USA
| | - C Grancea
- "Stefan S. Nicolau" Institute of Virology, Bucharest, Romania
| | - A Temereanca
- "Stefan S. Nicolau" Institute of Virology, Bucharest, Romania
| | - A Bharti
- University of California San Diego, La Jolla, CA, USA
| | - C L Achim
- University of California San Diego, La Jolla, CA, USA
| | - S Letendre
- University of California San Diego, La Jolla, CA, USA
| | - S M Ruta
- "Stefan S. Nicolau" Institute of Virology, Bucharest, Romania
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Tanaka N, Ashour D, Dratz E, Halonen S. Use of human induced pluripotent stem cell-derived neurons as a model for Cerebral Toxoplasmosis. Microbes Infect 2016; 18:496-504. [PMID: 27083472 DOI: 10.1016/j.micinf.2016.03.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/24/2016] [Accepted: 03/24/2016] [Indexed: 12/11/2022]
Abstract
Toxoplasma gondii is a ubiquitous protozoan parasite with approximately one-third of the worlds' population chronically infected. In chronically infected individuals, the parasite resides primarily in cysts within neurons in the central nervous system. The chronic infection in immunocompetent individuals has been considered to be asymptomatic but increasing evidence indicates the chronic infection can lead to neuropsychiatric disorders such as Schizophrenia, prenatal depression and suicidal thoughts. A better understanding of the mechanism(s) by which the parasite exerts effects on human behavior is limited due to lack of suitable human neuronal models. In this paper, we report the use of human neurons derived from normal cord blood CD34+ cells generated via genetic reprogramming, as an in vitro model for the study T. gondii in neurons. This culture method resulted in a relatively pure monolayer of induced human neuronal-like cells that stained positive for neuronal markers, MAP2, NFL, NFH and NeuN. These induced human neuronal-like cells (iHNs) were efficiently infected by the Prugniad strain of the parasite and supported replication of the tachyzoite stage and development of the cyst stage. Infected iHNs could be maintained through 5 days of infection, allowing for formation of large cysts. This induced human neuronal model represents a novel culture method to study both tachyzoite and bradyzoite stages of T. gondii in human neurons.
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Affiliation(s)
- Naomi Tanaka
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT 59717, USA
| | - Danah Ashour
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT 59717, USA
| | - Edward Dratz
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Sandra Halonen
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT 59717, USA.
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Cabral CM, Tuladhar S, Dietrich HK, Nguyen E, MacDonald WR, Trivedi T, Devineni A, Koshy AA. Neurons are the Primary Target Cell for the Brain-Tropic Intracellular Parasite Toxoplasma gondii. PLoS Pathog 2016; 12:e1005447. [PMID: 26895155 PMCID: PMC4760770 DOI: 10.1371/journal.ppat.1005447] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 01/19/2016] [Indexed: 11/17/2022] Open
Abstract
Toxoplasma gondii, a common brain-tropic parasite, is capable of infecting most nucleated cells, including astrocytes and neurons, in vitro. Yet, in vivo, Toxoplasma is primarily found in neurons. In vitro data showing that interferon-γ-stimulated astrocytes, but not neurons, clear intracellular parasites suggest that neurons alone are persistently infected in vivo because they lack the ability to clear intracellular parasites. Here we test this theory by using a novel Toxoplasma-mouse model capable of marking and tracking host cells that directly interact with parasites, even if the interaction is transient. Remarkably, we find that Toxoplasma shows a strong predilection for interacting with neurons throughout CNS infection. This predilection remains in the setting of IFN-γ depletion; infection with parasites resistant to the major mechanism by which murine astrocytes clear parasites; or when directly injecting parasites into the brain. These findings, in combination with prior work, strongly suggest that neurons are not incidentally infected, but rather they are Toxoplasma's primary in vivo target.
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Affiliation(s)
- Carla M Cabral
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Shraddha Tuladhar
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
| | - Hans K Dietrich
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Elizabeth Nguyen
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Wes R MacDonald
- Undergraduate Biology Research Program, University of Arizona, Tucson, Arizona, United States of America
| | - Tapasya Trivedi
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Asha Devineni
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Anita A Koshy
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America.,Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America.,Department of Neurology, University of Arizona, Tucson, Arizona, United States of America
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Mammari N, Vignoles P, Halabi MA, Dardé ML, Courtioux B. Interferon gamma effect on immune mediator production in human nerve cells infected by two strains of Toxoplasma gondii. ACTA ACUST UNITED AC 2015; 22:39. [PMID: 26692261 PMCID: PMC4686326 DOI: 10.1051/parasite/2015039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/29/2015] [Indexed: 11/23/2022]
Abstract
Interferon gamma (IFN-γ) is the major immune mediator that prevents toxoplasmic encephalitis in murine models. The lack of IFN-γ secretion causes reactivation of latent T. gondii infection that may confer a risk for severe toxoplasmic encephalitis. We analyse the effect of IFN-γ on immune mediator production and parasite multiplication in human nerve cells infected by tachyzoites of two T. gondii strains (RH and PRU). IFN-γ decreased the synthesis of MCP-1, G-CSF, GM-CSF and Serpin E1 in all cell types. It decreased IL-6, migration inhibitory factor (MIF) and GROα synthesis only in endothelial cells, while it increased sICAM and Serpin E1 synthesis only in neurons. The PRU strain burden increased in all nerve cells and in contrast, RH strain replication was controlled in IFN-γ-stimulated microglial and endothelial cells but not in IFN-γ-stimulated neurons. The proliferation of the PRU strain in all stimulated cells could be a specific effect of this strain on the host cell.
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Affiliation(s)
- Nour Mammari
- Univ. Limoges, UMR-S 1094, Tropical Neuroepidemiology, Institute of Neuroepidemiology and Tropical Neurology, CNRS FR 3503 GEIST, 87000 Limoges, France
| | - Philippe Vignoles
- Univ. Limoges, UMR-S 1094, Tropical Neuroepidemiology, Institute of Neuroepidemiology and Tropical Neurology, CNRS FR 3503 GEIST, 87000 Limoges, France
| | - Mohamad Adnan Halabi
- UMR CNRS 7276, FR 3503 GEIST, Faculty of Pharmacy, University of Limoges, 87000 Limoges, France
| | - Marie-Laure Dardé
- Univ. Limoges, UMR-S 1094, Tropical Neuroepidemiology, Institute of Neuroepidemiology and Tropical Neurology, CNRS FR 3503 GEIST, 87000 Limoges, France - CHU Limoges, Department of Parasitology, and Biological Resource Centre for Toxoplasma, 87000 Limoges, France
| | - Bertrand Courtioux
- Univ. Limoges, UMR-S 1094, Tropical Neuroepidemiology, Institute of Neuroepidemiology and Tropical Neurology, CNRS FR 3503 GEIST, 87000 Limoges, France
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Reich M, Becker MD, Mackensen F. Influence of drug therapy on the risk of recurrence of ocular toxoplasmosis. Br J Ophthalmol 2015; 100:195-9. [DOI: 10.1136/bjophthalmol-2015-306650] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 06/20/2015] [Indexed: 11/04/2022]
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Parlog A, Schlüter D, Dunay IR. Toxoplasma gondii-induced neuronal alterations. Parasite Immunol 2015; 37:159-70. [PMID: 25376390 DOI: 10.1111/pim.12157] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 10/31/2014] [Indexed: 12/13/2022]
Abstract
The zoonotic pathogen Toxoplasma gondii infects over 30% of the human population. The intracellular parasite can persist lifelong in the CNS within neurons modifying their function and structure, thus leading to specific behavioural changes of the host. In recent years, several in vitro studies and murine models have focused on the elucidation of these modifications. Furthermore, investigations of the human population have correlated Toxoplasma seropositivity with changes in neurological functions; however, the complex underlying mechanisms of the subtle behavioural alteration are still not fully understood. The parasites are able to induce direct modifications in the infected cells, for example by altering dopamine metabolism, by functionally silencing neurons as well as by hindering apoptosis. Moreover, indirect effects of the peripheral immune system and alterations of the immune status of the CNS, observed during chronic infection, might also contribute to changes in neuronal connectivity and synaptic plasticity. In this review, we will provide an overview and highlight recent advances, which describe changes in the neuronal function and morphology upon T. gondii infection.
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Affiliation(s)
- A Parlog
- Institute of Medical Microbiology and Hospital Hygiene, Otto-von-Guericke University, Magdeburg, Germany
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Schlüter D, Däubener W, Schares G, Groß U, Pleyer U, Lüder C. Animals are key to human toxoplasmosis. Int J Med Microbiol 2014; 304:917-29. [PMID: 25240467 DOI: 10.1016/j.ijmm.2014.09.002] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Toxoplasma gondii is an extremely sucessfull protozoal parasite which infects almost all mamalian species including humans. Approximately 30% of the human population worldwide is chronically infected with T. gondii. In general, human infection is asymptomatic but the parasite may induce severe disease in fetuses and immunocompromised patients. In addition, T. gondii may cause sight-threatening posterior uveitis in immunocompetent patients. Apart from few exceptions, humans acquire T. gondii from animals. Both, the oral uptake of T. gondii oocysts released by specific hosts, i.e. felidae, and of cysts persisting in muscle cells of animals result in human toxoplasmosis. In the present review, we discuss recent new data on the cell biology of T. gondii and parasite diversity in animals. In addition, we focus on the impact of these various parasite strains and their different virulence on the clinical outcome of human congenital toxoplasmosis and T. gondii uveitis.
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Affiliation(s)
- Dirk Schlüter
- Institute of Medical Microbiology, Infection Control and Prevention, Otto-von-Guericke-University, Magdeburg, Germany; Helmholtz Centre for Infection Research, Braunschweig, Germany.
| | - Walter Däubener
- Institute of Medical Microbiology and Hospital Hygiene, Heinrich-Heine-University, Düsseldorf, Germany
| | - Gereon Schares
- Institute of Epidemiology, Friedrich-Loeffler-Institute, Greifswald-Insel Riems, Germany
| | - Uwe Groß
- Institute for Medical Microbiology, University Medical Center, Göttingen, Germany
| | - Uwe Pleyer
- Eye Clinic, Charité Universitätsmedizin, Berlin, Germany
| | - Carsten Lüder
- Institute for Medical Microbiology, University Medical Center, Göttingen, Germany
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Mammari N, Vignoles P, Halabi MA, Darde ML, Courtioux B. In vitro infection of human nervous cells by two strains of Toxoplasma gondii: a kinetic analysis of immune mediators and parasite multiplication. PLoS One 2014; 9:e98491. [PMID: 24886982 PMCID: PMC4041771 DOI: 10.1371/journal.pone.0098491] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 05/02/2014] [Indexed: 01/11/2023] Open
Abstract
The severity of toxoplasmic infection depends mainly on the immune status of the host, but also on the Toxoplasma gondii strains, which differ by their virulence profile. The relationship between the human host and T. gondii has not yet been elucidated because few studies have been conducted on human models. The immune mechanisms involved in the persistence of T. gondii in the brains of immunocompetent subjects and during the reactivation of latent infections are still unclear. In this study, we analyzed the kinetics of immune mediators in human nervous cells in vitro, infected with two strains of T. gondii. Human neuroblast cell line (SH SY5Y), microglial (CMH5) and endothelial cells (Hbmec) were infected separately by RH (type I) or PRU (type II) strains for 8 h, 14 h, 24 h and 48 h (ratio 1 cell: 2 tachyzoites). Pro-inflammatory protein expression was different between the two strains and among different human nervous cells. The cytokines IL-6, IL-8 and the chemokines MCP-1 and GROα, and SERPIN E1 were significantly increased in CMH5 and SH SY5Y at 24 h pi. At this point of infection, the parasite burden declined in microglial cells and neurons, but remained high in endothelial cells. This differential effect on the early parasite multiplication may be correlated with a higher production of immune mediators by neurons and microglial cells compared to endothelial cells. Regarding strain differences, PRU strain, but not RH strain, stimulates all cells to produce pro-inflammatory growth factors, G-CSF and GM-CSF. These proteins could increase the inflammatory effect of this type II strain. These results suggest that the different protein expression profiles depend on the parasitic strain and on the human nervous cell type, and that this could be at the origin of diverse brain lesions caused by T. gondii.
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Affiliation(s)
- Nour Mammari
- National Institute of Health and Medical Research 1094, Tropical Neuroepidemiology Institute, Limoges, France; University of Limoges, National Center for Scientific Research France 3503 Institute of Genomic, Environment, Immunity, Health and Therapy, Limoges, France
- * E-mail:
| | - Philippe Vignoles
- National Institute of Health and Medical Research 1094, Tropical Neuroepidemiology Institute, Limoges, France; University of Limoges, National Center for Scientific Research France 3503 Institute of Genomic, Environment, Immunity, Health and Therapy, Limoges, France
| | - Mohamad Adnan Halabi
- National Center for Scientific Research France 7276, France 3503 Institute of Genomic, Environment, Immunity, Health and Therapy, University of Limoges, Faculty of Pharmacy, Limoges, France
| | - Marie Laure Darde
- National Institute of Health and Medical Research 1094, Tropical Neuroepidemiology Institute, Limoges, France; University of Limoges, National Center for Scientific Research France 3503 Institute of Genomic, Environment, Immunity, Health and Therapy, Limoges, France
- Universitary Hospital, Department of Parasitology, Biological Resource Centre for Toxoplasma, Limoges, France
| | - Bertrand Courtioux
- National Institute of Health and Medical Research 1094, Tropical Neuroepidemiology Institute, Limoges, France; University of Limoges, National Center for Scientific Research France 3503 Institute of Genomic, Environment, Immunity, Health and Therapy, Limoges, France
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Nau R, Ribes S, Djukic M, Eiffert H. Strategies to increase the activity of microglia as efficient protectors of the brain against infections. Front Cell Neurosci 2014; 8:138. [PMID: 24904283 PMCID: PMC4033068 DOI: 10.3389/fncel.2014.00138] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 05/30/2014] [Indexed: 12/24/2022] Open
Abstract
In healthy individuals, infections of the central nervous system (CNS) are comparatively rare. Based on the ability of microglial cells to phagocytose and kill pathogens and on clinical findings in immunocompromised patients with CNS infections, we hypothesize that an intact microglial function is crucial to protect the brain from infections. Phagocytosis of pathogens by microglial cells can be stimulated by agonists of receptors of the innate immune system. Enhancing this pathway to increase the resistance of the brain to infections entails the risk of inducing collateral damage to the nervous tissue. The diversity of microglial cells opens avenue to selectively stimulate sub-populations responsible for the defence against pathogens without stimulating sub-populations which are responsible for collateral damage to the nervous tissue. Palmitoylethanolamide (PEA), an endogenous lipid, increased phagocytosis of bacteria by microglial cells in vitro without a measurable proinflammatory effect. It was tested clinically apparently without severe side effects. Glatiramer acetate increased phagocytosis of latex beads by microglia and monocytes, and dimethyl fumarate enhanced elimination of human immunodeficiency virus from infected macrophages without inducing a release of proinflammatory compounds. Therefore, the discovery of compounds which stimulate the elimination of pathogens without collateral damage of neuronal structures appears an achievable goal. PEA and, with limitations, glatiramer acetate and dimethyl fumarate appear promising candidates.
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Affiliation(s)
- Roland Nau
- Department of Neuropathology, University Medical Centre Göttingen Göttingen, Germany ; Department of Geriatrics, Evangelisches Krankenhaus Göttingen-Weende Göttingen, Germany
| | - Sandra Ribes
- Department of Neuropathology, University Medical Centre Göttingen Göttingen, Germany
| | - Marija Djukic
- Department of Neuropathology, University Medical Centre Göttingen Göttingen, Germany ; Department of Geriatrics, Evangelisches Krankenhaus Göttingen-Weende Göttingen, Germany
| | - Helmut Eiffert
- Department of Clinical Microbiology, University Medical Centre Göttingen Göttingen, Germany
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Prandota J. Possible link between Toxoplasma gondii and the anosmia associated with neurodegenerative diseases. Am J Alzheimers Dis Other Demen 2014; 29:205-14. [PMID: 24413543 PMCID: PMC10852608 DOI: 10.1177/1533317513517049] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Toxoplasma gondii is an intracellular protozoan infecting 30% to 50% of global human population. Recently, it was suggested that chronic latent neuroinflammation caused by the parasite may be responsible for the development of several neurodegenerative diseases manifesting with the loss of smell. Studies in animals inoculated with the parasite revealed cysts in various regions of the brain, including olfactory bulb. Development of behavioral changes was paralleled by the preferential persistence of cysts in defined anatomic structures of the brain, depending on the host, strain of the parasite, its virulence, and route of inoculation. Olfactory dysfunction reported in Alzheimer's disease, multiple sclerosis, and schizophrenia was frequently associated with the significantly increased serum anti-T gondii immunoglobulin G antibody levels. Damage of the olfactory system may be also at least in part responsible for the development of depression because T gondii infection worsened mood in such patients, and the olfactory bulbectomized rat serves as a model of depression.
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Affiliation(s)
- Joseph Prandota
- Department of Social Pediatrics, Faculty of Health Sciences, Wroclaw Medical University, Wroclaw, Poland
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Abstract
Proper development and function of the mammalian central nervous system (CNS) depend critically on the activity of parenchymal sentinels referred to as microglia. Although microglia were first described as ramified brain-resident phagocytes, research conducted over the past century has expanded considerably upon this narrow view and ascribed many functions to these dynamic CNS inhabitants. Microglia are now considered among the most versatile cells in the body, possessing the capacity to morphologically and functionally adapt to their ever-changing surroundings. Even in a resting state, the processes of microglia are highly dynamic and perpetually scan the CNS. Microglia are in fact vital participants in CNS homeostasis, and dysregulation of these sentinels can give rise to neurological disease. In this review, we discuss the exciting developments in our understanding of microglial biology, from their developmental origin to their participation in CNS homeostasis and pathophysiological states such as neuropsychiatric disorders, neurodegeneration, sterile injury responses, and infectious diseases. We also delve into the world of microglial dynamics recently uncovered using real-time imaging techniques.
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Affiliation(s)
- Debasis Nayak
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892;
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Galván-Ramírez MDLL, Dueñas Jiménez JM, Rocío Rodríguez Pérez L, Troyo-Sanroman R, Ramírez-Herrera M, García-Iglesias T. Effect of nitaxozanide and pyrimethamine on astrocytes infected by Toxoplasma gondii in vitro. Arch Med Res 2013; 44:415-21. [PMID: 23973195 DOI: 10.1016/j.arcmed.2013.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 07/10/2013] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND AIMS T. gondii is a causal agent of encephalitis in immunocompromised patients. Pyrimethamine (PYR) has been the treatment of choice for toxoplasmosis. The aim of this study was to analyze the effect of nitazoxanide and pyrimethamine on astrocytes infected with T. gondii in vitro. METHODS Rat astrocytes were cultured and infected with T. gondii. The effect of nitazoxanide (10, 20 and 30 μg/mL) and pyrimethamine (7, 10 and 13 μg/mL) on astrocytes infected was evaluated at 24 and 48 h post-infection. Tachyzoites and astrocytes were detected by the immunocytochemical method. T. gondii viability in astrocytes infected and treated with NTZ and PYR as well as NTZ and PYR cytotoxicity on astrocytes in vitro were evaluated by the MTT assay. RESULTS The number of parasites in astrocytes treated with the drugs was significantly reduced when compared to control (p <0.001) at 24 and 48 h. Nitazoxanide produced 97% T. gondii death in a concentration of 10 μg/mL in 48 h infected astrocytes. At 48 h, the death rate of T. gondii was higher when treated with nitazoxanide than with pyrimethamine. A higher toxicity rate in astrocyte was observed when using pyrimethamine at 40 μg/mL. CONCLUSIONS Nitazoxanide reduced T. gondii infection more efficiently than pyrimethamine and is not cytotoxic to astrocytes at the administered dose.
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Affiliation(s)
- Ma de la Luz Galván-Ramírez
- Laboratorio de Neurofisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, Mexico.
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Contreras-Ochoa CO, Lagunas-Martínez A, Belkind-Gerson J, Díaz-Chávez J, Correa D. Toxoplasma gondii invasion and replication within neonate mouse astrocytes and changes in apoptosis related molecules. Exp Parasitol 2013; 134:256-65. [DOI: 10.1016/j.exppara.2013.03.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 03/11/2013] [Accepted: 03/17/2013] [Indexed: 02/02/2023]
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Gaji RY, Huynh MH, Carruthers VB. A novel high throughput invasion screen identifies host actin regulators required for efficient cell entry by Toxoplasma gondii. PLoS One 2013; 8:e64693. [PMID: 23741372 PMCID: PMC3669402 DOI: 10.1371/journal.pone.0064693] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 04/17/2013] [Indexed: 01/08/2023] Open
Abstract
Toxoplasma gondii critically relies on cell invasion as a survival strategy to evade immune clearance during infection. Although it was widely thought that Toxoplasma entry is parasite directed and that the host cell is largely a passive victim, recent studies have suggested that host components such as microfilaments and microtubules indeed contribute to entry. Hence to identify additional host factors, we performed a high-throughput siRNA screen of a human siRNA library targeting druggable proteins using a novel inducible luciferase based invasion assay. The top 100 hits from the primary screen that showed the strongest decreases in invasion were subjected to confirmation by secondary screening, revealing 24 proteins that are potentially involved in Toxoplasma entry into host cells. Interestingly, 6 of the hits appear to affect parasite invasion by modifying host cell actin dynamics, resulting in increased deposition of F-actin at the periphery of the cell. These findings support the emerging notion that host actin dynamics are important for Toxoplasma invasion along with identifying several novel host factors that potentially participate in parasite entry.
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Affiliation(s)
- Rajshekhar Y. Gaji
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - My-Hang Huynh
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Vern B. Carruthers
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- * E-mail:
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