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Debs SR, Conn I, Navaneethan B, Penklis AG, Meyer U, Killcross S, Weickert CS, Purves-Tyson TD. Maternal immune activation and estrogen receptor modulation induce sex-specific dopamine-related behavioural and molecular alterations in adult rat offspring. Brain Behav Immun 2024; 118:236-251. [PMID: 38431238 DOI: 10.1016/j.bbi.2024.02.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 02/08/2024] [Accepted: 02/27/2024] [Indexed: 03/05/2024] Open
Abstract
Dopamine dysregulation contributes to psychosis and cognitive deficits in schizophrenia that can be modelled in rodents by inducing maternal immune activation (MIA). The selective estrogen receptor (ER) modulator, raloxifene, can improve psychosis and cognition in men and women with schizophrenia. However, few studies have examined how raloxifene may exert its therapeutic effects in mammalian brain in both sexes during young adulthood (age relevant to most prevalent age at diagnosis). Here, we tested the extent to which raloxifene alters dopamine-related behaviours and brain transcripts in young adult rats, both control and MIA-exposed females and males. We found that raloxifene increased amphetamine (AMPH)-induced locomotor activity in female controls, and in contrast, raloxifene reduced AMPH-induced locomotor activity in male MIA offspring. We did not detect overt prepulse inhibition (PPI) deficits in female or male MIA offspring, yet raloxifene enhanced PPI in male MIA offspring. Whereas, raloxifene ameliorated increased startle responsivity in female MIA offspring. In the substantia nigra (SN), we found reduced Drd2s mRNA in raloxifene-treated female offspring with or without MIA, and increased Comt mRNA in placebo-treated male MIA offspring relative to placebo-treated controls. These data demonstrate an underlying dopamine dysregulation in MIA animals that can become more apparent with raloxifene treatment, and may involve selective alterations in dopamine receptor levels and dopamine breakdown processes in the SN. Our findings support sex-specific, differential behavioural responses to ER modulation in MIA compared to control offspring, with beneficial effects of raloxifene treatment on dopamine-related behaviours relevant to schizophrenia found in male MIA offspring only.
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Affiliation(s)
- Sophie R Debs
- Preclinical Neuropsychiatry Laboratory, Neuroscience Research Australia, Sydney, Australia; Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia; Discipline of Psychiatry & Mental Health, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Illya Conn
- Preclinical Neuropsychiatry Laboratory, Neuroscience Research Australia, Sydney, Australia; Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia
| | - Brendan Navaneethan
- Preclinical Neuropsychiatry Laboratory, Neuroscience Research Australia, Sydney, Australia
| | - Andriane G Penklis
- Preclinical Neuropsychiatry Laboratory, Neuroscience Research Australia, Sydney, Australia; Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia
| | - Urs Meyer
- Institute of Pharmacology and Toxicology, University of Zürich-Vetsuisse, Zürich, Switzerland; Switzerland Neuroscience Centre Zürich, Zürich, Switzerland
| | - Simon Killcross
- School of Psychology, University of New South Wales, Sydney, Australia
| | - Cynthia Shannon Weickert
- Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia; Discipline of Psychiatry & Mental Health, Faculty of Medicine, University of New South Wales, Sydney, Australia; Department of Neuroscience & Physiology, Upstate Medical University, Syracuse, USA
| | - Tertia D Purves-Tyson
- Preclinical Neuropsychiatry Laboratory, Neuroscience Research Australia, Sydney, Australia; Discipline of Psychiatry & Mental Health, Faculty of Medicine, University of New South Wales, Sydney, Australia.
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Fernandez RF, Wilson ES, Diaz V, Martínez-Gardeazabal J, Foguth R, Cannon JR, Jackson SN, Hermann BP, Eells JB, Ellis JM. Lipid metabolism in dopaminergic neurons influences light entrainment. J Neurochem 2023; 165:379-390. [PMID: 36815399 PMCID: PMC10155601 DOI: 10.1111/jnc.15793] [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: 07/25/2022] [Revised: 12/20/2022] [Accepted: 02/07/2023] [Indexed: 02/24/2023]
Abstract
Dietary lipids, particularly omega-3 polyunsaturated fatty acids, are speculated to impact behaviors linked to the dopaminergic system, such as movement and control of circadian rhythms. However, the ability to draw a direct link between dopaminergic omega-3 fatty acid metabolism and behavioral outcomes has been limited to the use of diet-based approaches, which are confounded by systemic effects. Here, neuronal lipid metabolism was targeted in a diet-independent manner by manipulation of long-chain acyl-CoA synthetase 6 (ACSL6) expression. ACSL6 performs the initial reaction for cellular fatty acid metabolism and prefers the omega-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA). The loss of Acsl6 in mice (Acsl6-/- ) depletes neuronal membranes of DHA content and results in phenotypes linked to dopaminergic control, such as hyperlocomotion, impaired short-term spatial memory, and imbalances in dopamine neurochemistry. To investigate the role of dopaminergic ACSL6 on these outcomes, a dopaminergic neuron-specific ACSL6 knockout mouse was generated (Acsl6DA-/- ). Acsl6DA-/- mice demonstrated hyperlocomotion and imbalances in striatal dopamine neurochemistry. Circadian rhythms of both the Acsl6-/- and the Acsl6DA-/- mice were similar to control mice under basal conditions. However, upon light entrainment, a mimetic of jet lag, both the complete knockout of ACSL6 and the dopaminergic-neuron-specific loss of ACSL6 resulted in a longer recovery to entrainment compared to control mice. In conclusion, these data demonstrate that ACSL6 in dopaminergic neurons alters dopamine metabolism and regulation of light entrainment suggesting that DHA metabolism mediated by ACSL6 plays a role in dopamine neuron biology.
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Affiliation(s)
- Regina F. Fernandez
- Department of Physiology and East Carolina Diabetes and Obesity institute, Brody School of Medicine at East Carolina University, Greenville, North Carolina, USA
| | - Emily S. Wilson
- Department of Physiology and East Carolina Diabetes and Obesity institute, Brody School of Medicine at East Carolina University, Greenville, North Carolina, USA
| | - Victoria Diaz
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas San Antonio, San Antonio, Texas, USA
| | | | - Rachel Foguth
- School of Health Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Jason R. Cannon
- School of Health Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Shelley N. Jackson
- National Institute on Drug Abuse, Intramural Research Program, Translational Analytical Core, Baltimore, Maryland, USA
| | - Brian P. Hermann
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas San Antonio, San Antonio, Texas, USA
| | - Jeffrey B. Eells
- Department of Anatomy and Cell Biology, East Carolina University, Brody School of Medicine, Greenville, North Carolina, USA
| | - Jessica M. Ellis
- Department of Physiology and East Carolina Diabetes and Obesity institute, Brody School of Medicine at East Carolina University, Greenville, North Carolina, USA
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3
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Guerrin CGJ, Doorduin J, Sommer IE, de Vries EFJ. The dual hit hypothesis of schizophrenia: Evidence from animal models. Neurosci Biobehav Rev 2021; 131:1150-1168. [PMID: 34715148 DOI: 10.1016/j.neubiorev.2021.10.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 10/21/2021] [Accepted: 10/24/2021] [Indexed: 12/16/2022]
Abstract
Schizophrenia is a heterogeneous psychiatric disorder, which can severely impact social and professional functioning. Epidemiological and clinical studies show that schizophrenia has a multifactorial aetiology comprising genetic and environmental risk factors. Although several risk factors have been identified, it is still not clear how they result in schizophrenia. This knowledge gap, however, can be investigated in animal studies. In this review, we summarise animal studies regarding molecular and cellular mechanisms through which genetic and environmental factors may affect brain development, ultimately causing schizophrenia. Preclinical studies suggest that early environmental risk factors can affect the immune, GABAergic, glutamatergic, or dopaminergic system and thus increase the susceptibility to another risk factor later in life. A second insult, like social isolation, stress, or drug abuse, can further disrupt these systems and the interactions between them, leading to behavioural abnormalities. Surprisingly, first insults like maternal infection and early maternal separation can also have protective effects. Single gene mutations associated with schizophrenia did not have a major impact on the susceptibility to subsequent environmental hits.
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Affiliation(s)
- Cyprien G J Guerrin
- Department of Nuclear Medicine and Medical Imaging, University of Groningen, University Medical Centre Groningen, Hanzeplein 1, 9713, GZ, Groningen, the Netherlands
| | - Janine Doorduin
- Department of Nuclear Medicine and Medical Imaging, University of Groningen, University Medical Centre Groningen, Hanzeplein 1, 9713, GZ, Groningen, the Netherlands
| | - Iris E Sommer
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713, GZ, Groningen, the Netherlands
| | - Erik F J de Vries
- Department of Nuclear Medicine and Medical Imaging, University of Groningen, University Medical Centre Groningen, Hanzeplein 1, 9713, GZ, Groningen, the Netherlands.
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4
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Social preference is maintained in mice with impaired startle reflex and glutamate/D-serine imbalance induced by chronic cerebral toxoplasmosis. Sci Rep 2021; 11:14029. [PMID: 34234237 PMCID: PMC8263783 DOI: 10.1038/s41598-021-93504-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 06/11/2021] [Indexed: 02/06/2023] Open
Abstract
Toxoplasma gondii is an opportunistic protozoan pathogen with a wide geographic distribution. The chronic phase of toxoplasmosis is often asymptomatic in humans and is characterized by tissue cysts throughout the central nervous system and muscle cells. T. gondii and other pathogens with tropism for the central nervous system are considered risk factors in the etiology of several neuropsychiatric disorders, such as schizophrenia and bipolar disorder, besides neurological diseases. Currently, it is known that cerebral toxoplasmosis increases dopamine levels in the brain and it is related to behavioral changes in animals and humans. Here we evaluate whether chronic T. gondii infection, using the cystogenic ME-49 strain, could induce behavioral alterations associated with neuropsychiatric disorders and glutamatergic neurotransmission dysfunction. We observed that the startle amplitude is reduced in the infected animals as well as glutamate and D-serine levels in prefrontal cortical and hippocampal tissue homogenates. Moreover, we did not detect alterations in social preference and spontaneous alternation despite severe motor impairment. Thus, we conclude that behavioral and cognitive aspects are maintained even though severe neural damage is observed by chronic infection of C57Bl/6 mice with the ME-49 strain.
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Salem DA, Salem NA, Hendawy SR. Association between Toxoplasma gondii infection and metabolic syndrome in obese adolescents: A possible immune-metabolic link. Parasitol Int 2021; 83:102343. [PMID: 33831579 DOI: 10.1016/j.parint.2021.102343] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/27/2021] [Accepted: 04/01/2021] [Indexed: 01/22/2023]
Abstract
Background Toxoplasmosis as a global disease is considered as a triggering factor responsible for development of several clinical diseases. However, Toxoplasma gondii (T. gondii) is an understudied parasite of potential interest in obesity research. The current study aimed to explore the role of latent T. gondii infection in the pathogenesis of metabolic syndrome (MetS) in obese adolescents through studying the relationship between serum interferon-gamma [IFN-γ] and serum chemerin in context of MetS components. Methods Eighty-three obese adolescents were serologically screened for T. gondii-IgG antibodies and compared to 35 age-matched healthy T. gondii-seronegative controls. Participants were evaluated for anthropometric measurements, total-fat mass [FM], trunk-FM, serum lipid profile, IFN-γ, and chemerin levels. Homeostatic Model Assessment of insulin resistance (HOMA-IR) was calculated. Results The prevalence of MetS was significantly higher within obese T. gondii-seropositive group compared to obese T. gondii-seronegative group (P = 0.033). Seropositive obese MetS group displayed significantly higher trunk-FM, HOMA-IR, chemerin, and IFN-γ compared to seronegative obese MetS group. Serum chemerin and IFN-γ were strongly correlated (P < 0.001) and were positively correlated with BMI, WC, total-FM, trunk-FM, HOMA-IR, cholesterol, triglycerides and negatively correlated with HDLC. HOMA-IR was a common predictor for serum chemerin (P = 0.030) and IFN-γ (P < 0.001). Conclusions The study results suggest that T. gondii infection may exert an immune-metabolic effect that may have a potential role in the development of MetS among obese adolescents.
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Affiliation(s)
- Doaa A Salem
- Medical Parasitology Department, Faculty of Medicine, Mansoura University, Egypt.
| | - Nanees A Salem
- Department of Pediatrics, Pediatric Endocrinology Unit, Faculty of Medicine, Mansoura University, Egypt
| | - Shimaa R Hendawy
- Department of Clinical Pathology, Faculty of Medicine, Mansoura University, Egypt
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6
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Tong WH, Pavey C, O'Handley R, Vyas A. Behavioral biology of Toxoplasma gondii infection. Parasit Vectors 2021; 14:77. [PMID: 33494777 PMCID: PMC7831251 DOI: 10.1186/s13071-020-04528-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 12/07/2020] [Indexed: 12/14/2022] Open
Abstract
Toxoplasma gondii is a protozoan parasite with a complex life cycle and a cosmopolitan host range. The asexual part of its life cycle can be perpetually sustained in a variety of intermediate hosts through a combination of carnivory and vertical transmission. However, T. gondii produces gametes only in felids after the predation of infected intermediate hosts. The parasite changes the behavior of its intermediate hosts by reducing their innate fear to cat odors and thereby plausibly increasing the probability that the definitive host will devour the infected host. Here, we provide a short description of such parasitic behavioral manipulation in laboratory rodents infected with T. gondii, along with a bird's eye view of underpinning biological changes in the host. We also summarize critical gaps and opportunities for future research in this exciting research area with broad implications in the transdisciplinary study of host-parasite relationships.
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Affiliation(s)
- Wen Han Tong
- School of Biological Sciences, Nanyang Technological University (SBS-NTU), 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Chris Pavey
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Land and Water, Darwin, Australia
| | - Ryan O'Handley
- School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, Australia
| | - Ajai Vyas
- School of Biological Sciences, Nanyang Technological University (SBS-NTU), 60 Nanyang Drive, Singapore, 637551, Singapore.
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Abo-Al-Ela HG. Toxoplasmosis and Psychiatric and Neurological Disorders: A Step toward Understanding Parasite Pathogenesis. ACS Chem Neurosci 2020; 11:2393-2406. [PMID: 31268676 DOI: 10.1021/acschemneuro.9b00245] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Toxoplasmosis, a disease that disrupts fetal brain development and severely affects the host's brain, has been linked to many behavioral and neurological disorders. There is growing interest in how a single-celled neurotropic parasite, Toxoplasma gondii, can control or change the behavior of the host as well as how it dominates the host's neurons. Secrets beyond these could be answered by decoding the Toxoplasma gondii genome, unravelling the function of genomic sequences, and exploring epigenetics and mRNAs alterations, as well as the postulated mechanisms contributing to various neurological and psychiatric symptoms caused by this parasite. Substantial efforts have been made to elucidate the action of T. gondii on host immunity and the biology of its infection. However, the available studies on the molecular aspects of toxoplasmosis that affect central nervous system (CNS) circuits remain limited, and much research is still needed on this interesting topic. In my opinion, this parasite is a gift for studying the biology of the nervous system and related diseases. We should utilize the unique features of Toxoplasma, such as its abilities to modulate brain physiology, for neurological studies or as a possible tool or approach to cure neurological disease.
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Affiliation(s)
- Haitham G. Abo-Al-Ela
- Animal Health Research Institute, Agriculture Research Center, Shibin Al-Kom, El-Minufiya 7001, Egypt
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8
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Alsaady I, Tedford E, Alsaad M, Bristow G, Kohli S, Murray M, Reeves M, Vijayabaskar MS, Clapcote SJ, Wastling J, McConkey GA. Downregulation of the Central Noradrenergic System by Toxoplasma gondii Infection. Infect Immun 2019; 87:e00789-18. [PMID: 30510101 PMCID: PMC6346129 DOI: 10.1128/iai.00789-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 11/15/2018] [Indexed: 12/17/2022] Open
Abstract
Toxoplasma gondii is associated with physiological effects in the host. Dysregulation of catecholamines in the central nervous system has previously been observed in chronically infected animals. In the study described here, the noradrenergic system was found to be suppressed with decreased levels of norepinephrine (NE) in brains of infected animals and in infected human and rat neural cells in vitro The mechanism responsible for the NE suppression was found to be downregulation of dopamine β-hydroxylase (DBH) gene expression, encoding the enzyme that synthesizes norepinephrine from dopamine, with downregulation observed in vitro and in infected brain tissue, particularly in the dorsal locus coeruleus/pons region. The downregulation was sex specific, with males expressing reduced DBH mRNA levels whereas females were unchanged. Rather, DBH expression correlated with estrogen receptor in the female rat brains for this estrogen-regulated gene. DBH silencing was not a general response of neurons to infection, as human cytomegalovirus did not downregulate DBH expression. The noradrenergic-linked behaviors of sociability and arousal were altered in chronically infected animals, with a high correlation between DBH expression and infection intensity. A decrease in DBH expression in noradrenergic neurons can elevate dopamine levels, which provides a possible explanation for mixed observations of changes in this neurotransmitter with infection. Decreased NE is consistent with the loss of coordination and motor impairments associated with toxoplasmosis. Further, the altered norepinephrine synthesis observed here may, in part, explain behavioral effects of infection and associations with mental illness.
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Affiliation(s)
- Isra Alsaady
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Ellen Tedford
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Mohammad Alsaad
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Greg Bristow
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Shivali Kohli
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Matthew Murray
- Institute of Immunity & Transplantation, UCL Department of Virology, Division of Infection & Immunity, Royal Free Hospital, London, United Kingdom
| | - Matthew Reeves
- Institute of Immunity & Transplantation, UCL Department of Virology, Division of Infection & Immunity, Royal Free Hospital, London, United Kingdom
| | - M S Vijayabaskar
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Steven J Clapcote
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Jonathan Wastling
- Faculty of Natural Sciences, University of Keele, Newcastle-under-Lyme, United Kingdom
| | - Glenn A McConkey
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
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Kannan G, Prandovszky E, Severance E, Yolken RH, Pletnikov MV. A New T. gondii Mouse Model of Gene-Environment Interaction Relevant to Psychiatric Disease. SCIENTIFICA 2018; 2018:7590958. [PMID: 30631636 PMCID: PMC6305013 DOI: 10.1155/2018/7590958] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 10/11/2018] [Indexed: 06/09/2023]
Abstract
Infection with the protozoan parasite, Toxoplasma gondii (T. gondii), was linked to several psychiatric disorders. The exact mechanisms of a hypothesized contribution of T. gondii infection are poorly understood, and it appears that only a subset of seropositive individuals go on to develop a mental illness, suggesting genetic vulnerability. In order to stimulate mechanistic studies of how exposure to T. gondii could interact with genetic predisposition to psychiatric disorders, we have generated and characterized a mouse model of chronic T. gondii infection in BALB/c mice with inducible forebrain neuronal expression of a C-terminus truncated dominant-negative form of disrupted-in-schizophrenia 1 (DN-DISC1). In this gene-environment interaction (GxE) model, exposing control and DN-DISC1 male and female mice to T. gondii produced sex-dependent abnormalities in locomotor activity and prepulse inhibition of the acoustic startle. No genotype- or sex-dependent effects were found on levels of anti-Toxoplasma IgG antibodies or anti-NMDAR or C1q antibodies. Our work demonstrates that a psychiatric genetic risk factor, DN-DISC1, modulates the neurobehavioral effects of chronic T. gondii infection in a sex-dependent manner. The present T. gondii model of GxE provides a valuable experimental system for future mechanistic studies and evaluation of new treatments.
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Affiliation(s)
- Geetha Kannan
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Emese Prandovszky
- Stanley Neurovirology Laboratory, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Emily Severance
- Stanley Neurovirology Laboratory, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Robert H. Yolken
- Stanley Neurovirology Laboratory, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Mikhail V. Pletnikov
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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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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11
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Xiao J, Prandovszky E, Kannan G, Pletnikov MV, Dickerson F, Severance EG, Yolken RH. Toxoplasma gondii: Biological Parameters of the Connection to Schizophrenia. Schizophr Bull 2018; 44:983-992. [PMID: 29889280 PMCID: PMC6101499 DOI: 10.1093/schbul/sby082] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
It is increasingly evident that the brain is not truly an immune privileged site and that cells of the central nervous system are sensitive to the inflammation generated when the brain is fighting off infection. Among the many microorganisms that have access to the brain, the apicomplexan protozoan Toxoplasma gondii has been one of the most studied. This parasite has been associated with many neuropsychiatric disorders including schizophrenia. This article provides a comprehensive review of the status of Toxoplasma research in schizophrenia. Areas of interest include (1) the limitations and improvements of immune-based assays to detect these infections in humans, (2) recent discoveries concerning the schizophrenia-Toxoplasma association, (3) findings of Toxoplasma neuropathology in animal models related to schizophrenia pathogenesis, (4) interactions of Toxoplasma with the host genome, (5) gastrointestinal effects of Toxoplasma infections, and (6) therapeutic intervention of Toxoplasma infections.
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Affiliation(s)
- Jianchun Xiao
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD
| | - Emese Prandovszky
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD
| | - Geetha Kannan
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI
| | - Mikhail V Pletnikov
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Faith Dickerson
- Stanley Research Program, Sheppard Pratt Health System, Baltimore, MD
| | - Emily G Severance
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD
| | - Robert H Yolken
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD,To whom correspondence should be addressed; Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD 21287 USA; tel: +1-410-614-0004, fax: +1-410-955-3723, e-mail:
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12
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Khan A, Powell SB. Sensorimotor gating deficits in "two-hit" models of schizophrenia risk factors. Schizophr Res 2018; 198:68-83. [PMID: 29070440 PMCID: PMC5911431 DOI: 10.1016/j.schres.2017.10.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 10/03/2017] [Accepted: 10/06/2017] [Indexed: 02/07/2023]
Abstract
Genetic and environmental models of neuropsychiatric disease have grown exponentially over the last 20years. One measure that is often used to evaluate the translational relevance of these models to human neuropsychiatric disease is prepulse inhibition of startle (PPI), an operational measure of sensorimotor gating. Deficient PPI characterizes several neuropsychiatric disorders but has been most extensively studied in schizophrenia. It has become a useful tool in translational neuropharmacological and molecular genetics studies because it can be measured across species using almost the same experimental parameters. Although initial studies of PPI in rodents were pharmacological because of the robust predictive validity of PPI for antipsychotic efficacy, more recently, PPI has become standard common behavioral measures used in genetic and neurodevelopmental models of schizophrenia. Here we review "two hit" models of schizophrenia and discuss the utility of PPI as a tool in phenotyping these models of relevant risk factors. In the review, we consider approaches to rodent models of genetic and neurodevelopmental risk factors and selectively review "two hit" models of gene×environment and environment×environment interactions in which PPI has been measured.
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Affiliation(s)
- Asma Khan
- Department of Psychiatry, University of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093, United States; Research Service, VA San Diego Healthcare System, La Jolla, CA, United States
| | - Susan B Powell
- Department of Psychiatry, University of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093, United States; Research Service, VA San Diego Healthcare System, La Jolla, CA, United States.
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Sagud M, Vlatkovic S, Svob Strac D, Sviben M, Zivkovic M, Vilibic M, Vuksan-Cusa B, Mihaljevic-Peles A, Pivac N. Latent Toxoplasma gondii infection is associated with decreased serum triglyceride to high-density lipoprotein cholesterol ratio in male patients with schizophrenia. Compr Psychiatry 2018; 82:115-120. [PMID: 29477703 DOI: 10.1016/j.comppsych.2018.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 01/21/2018] [Accepted: 02/02/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Previous studies suggested a complex association between Toxoplasma gondii (TG) infection and host lipid metabolism. Both TG infection and metabolic disturbances are very common in patients with schizophrenia, but this relationship is not clear. METHODS In this cross-sectional study, we evaluated the association between TG seropositivity, serum lipid levels, body mass index (BMI) and metabolic syndrome (MetS) in 210 male inpatients with schizophrenia. RESULTS In our sample of schizophrenia patients, with the mean age of 43.90 ± 12.70 years, the rate of TG seropositivity was 52.38% and the prevalence of MetS was 17%. Patients with the TG antibodies had lower serum triglyceride levels and body weight compared to TG seronegative patients, despite having more frequently received antipsychotics (clozapine, olanzapine risperidone and quetiapine), which are well known to induce weight gain and metabolic abnormalities. However, the only significant change in metabolic parameters, observed in TG seropositive patients with schizophrenia, was decreased serum triglyceride to high-density lipoprotein cholesterol (HDL-C) ratio. No associations were observed between TG seropositivity and serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and glucose levels, waist circumference, BMI and the rate of MetS. CONCLUSION This is the first report of the association between TG infection and decreased serum triglyceride to HDL-C ratio in a sample of carefully selected men with chronic schizophrenia.
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Affiliation(s)
- Marina Sagud
- School of Medicine, University of Zagreb, Zagreb, Croatia; Clinical Hospital Centre Zagreb, Department of Psychiatry, Zagreb, Croatia
| | | | | | - Mario Sviben
- School of Medicine, University of Zagreb, Zagreb, Croatia; Microbiology Service, Croatian National Institute of Public Health, Zagreb, Croatia
| | | | - Maja Vilibic
- University Hospital Centre "Sisters of Mercy", Zagreb, Croatia
| | - Bjanka Vuksan-Cusa
- Clinical Hospital Centre Zagreb, Department of Psychiatry, Zagreb, Croatia; School of Medicine, University of Osijek, Osijek, Croatia; School of Medicine, University of Mostar, Mostar, Bosnia and Herzegovina
| | - Alma Mihaljevic-Peles
- School of Medicine, University of Zagreb, Zagreb, Croatia; Clinical Hospital Centre Zagreb, Department of Psychiatry, Zagreb, Croatia
| | - Nela Pivac
- Division of Molecular Medicine, Rudjer Boskovic Institute, Zagreb, Croatia
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14
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Toxoplasma gondii infection and schizophrenia: an inter-kingdom communication perspective. Curr Opin Infect Dis 2017; 29:311-8. [PMID: 27120002 DOI: 10.1097/qco.0000000000000265] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW The apicomplexan protozoan Toxoplasma gondii has a striking predilection for infecting the central nervous system and has been suggested as a risk factor for schizophrenia. Here, we address some of the mechanisms by which T. gondii achieves this by manipulating signaling pathways of the host brain cells. RECENT FINDINGS Recent years have brought notable progress in the understanding of how the opportunistic parasite T. gondii establishes a successful infection in mammalian brain by secreting effector molecules that manipulate multiple cell functions. Many pathways involved in this inter-kingdom signaling, such as dopaminergic, GABAergic and kynurenine pathways, also have key roles in the development of schizophrenia. More understanding of T. gondii-brain cell interaction holds the key to unlocking the mystery of T. gondii-mediated schizophrenia pathogenesis. SUMMARY T. gondii usurps a variety of host signaling pathways to ensure physiological adaptation, evasion of host immune defense systems, and efficient replication. A detailed knowledge of T. gondii signaling molecules involved in this cross-kingdom communication with host brain cells will probably provide novel means of pharmacologically manipulating host cellular pathways to promote efficient elimination of the parasite and may permit the development of new schizophrenia-modifying therapeutics.
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Kummari E, Guo-Ross S, Eells JB. Region Specific Effects of Aging and the Nurr1-Null Heterozygous Genotype on Dopamine Neurotransmission. NEUROCHEMISTRY & NEUROPHARMACOLOGY : OPEN ACCESS 2017; 3:114. [PMID: 28989991 PMCID: PMC5630175 DOI: 10.4172/2469-9780.1000114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The transcription factor Nurr1 is essential for dopamine neuron differentiation and is important in maintaining dopamine synthesis and neurotransmission in the adult. Reduced Nurr1 function, due to the Nurr1-null heterozygous genotype (+/-), impacts dopamine neuron function in a region specific manner resulting in a decrease in dopamine synthesis in the dorsal and ventral striatum and a decrease in tissue dopamine levels in the ventral striatum. Additionally, maintenance of tissue dopamine levels in the dorsal striatum and survival of nigrostriatal dopamine neurons with aging (>15 months) or after various toxicant treatments are impaired. To further investigate the effects of aging and the Nurr1-null heterozygous genotype, we measured regional tissue dopamine levels, dopamine neuron numbers, body weight, open field activity and rota-rod performance in young (3-5 months) and aged (15-17 months) wild-type +/+ and +/- mice. Behavioral tests revealed no significant differences in rota-rod performance or basal open field activity as a result of aging or genotype. The +/- mice did show a significant increase in open field activity after 3 min of restraint stress. No differences in tissue dopamine levels were found in the dorsal striatum. However, there were significant reductions in tissue dopamine levels in the ventral striatum, which was separated into the nucleus accumbens core and shell, in the aged +/- mice. These data indicate that the mesoaccumbens system is more susceptible to the combination of aging and the +/- genotype than the nigrostriatal system. Additionally, the effects of aging and the +/- genotype may be dependent on genetic background or housing conditions. As Nurr1 mutations have been implicated in a number of diseases associated with dopamine neurotransmission, further data is needed to understand why and how Nurr1 can have differential functions across different dopamine neuron populations in aging.
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Affiliation(s)
- Evangel Kummari
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
| | - Shirley Guo-Ross
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
| | - Jeffrey B Eells
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
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Neurophysiological Changes Induced by Chronic Toxoplasma gondii Infection. Pathogens 2017; 6:pathogens6020019. [PMID: 28513566 PMCID: PMC5488653 DOI: 10.3390/pathogens6020019] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 05/08/2017] [Accepted: 05/12/2017] [Indexed: 01/13/2023] Open
Abstract
Although the parasite Toxoplasma gondii is one of the most pervasive neurotropic pathogens in the world, the host-parasite interactions during CNS infection and the consequences of neurological infection are just beginning to be unraveled. The chronic stages of infection have been considered dormant, although several studies have found correlations of infection with an array of host behavioral changes. These may facilitate parasite transmission and impact neurological diseases. During infection, in addition to the presence of the parasites within neurons, host-mediated neuroimmune and hormonal responses to infection are also present. T. gondii induces numerous changes to host neurons during infection and globally alters host neurological signaling pathways, as discussed in this review. Understanding the neurophysiological changes in the host brain is imperative to understanding the parasitic mechanisms and to delineate the effects of this single-celled parasite on health and its contribution to neurological disease.
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17
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Klein RS, Garber C, Howard N. Infectious immunity in the central nervous system and brain function. Nat Immunol 2017; 18:132-141. [PMID: 28092376 DOI: 10.1038/ni.3656] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 12/02/2016] [Indexed: 11/09/2022]
Abstract
Inflammation is emerging as a critical mechanism underlying neurological disorders of various etiologies, yet its role in altering brain function as a consequence of neuroinfectious disease remains unclear. Although acute alterations in mental status due to inflammation are a hallmark of central nervous system (CNS) infections with neurotropic pathogens, post-infectious neurologic dysfunction has traditionally been attributed to irreversible damage caused by the pathogens themselves. More recently, studies indicate that pathogen eradication within the CNS may require immune responses that interfere with neural cell function and communication without affecting their survival. In this Review we explore inflammatory processes underlying neurological impairments caused by CNS infection and discuss their potential links to established mechanisms of psychiatric and neurodegenerative diseases.
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Affiliation(s)
- Robyn S Klein
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA.,Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA.,Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Charise Garber
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Nicole Howard
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA.,Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
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18
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Sex differences in animal models of schizophrenia shed light on the underlying pathophysiology. Neurosci Biobehav Rev 2016; 67:41-56. [DOI: 10.1016/j.neubiorev.2015.10.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 09/28/2015] [Accepted: 10/26/2015] [Indexed: 12/20/2022]
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19
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Kannan G, Crawford JA, Yang C, Gressitt KL, Ihenatu C, Krasnova IN, Cadet JL, Yolken RH, Severance EG, Pletnikov MV. Anti-NMDA receptor autoantibodies and associated neurobehavioral pathology in mice are dependent on age of first exposure to Toxoplasma gondii. Neurobiol Dis 2016; 91:307-14. [PMID: 26969530 DOI: 10.1016/j.nbd.2016.03.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 02/25/2016] [Accepted: 03/07/2016] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Toxoplasma gondii is a pathogen implicated in psychiatric disorders. As elevated antibodies to T. gondii are also present in non-symptomatic individuals, we hypothesized that the age during first exposure to the pathogen may affect symptom manifestation. We tested this hypothesis by evaluating neurobehavioral abnormalities and the immune response in mice following adolescent or adult T. gondii infection. METHODS Mice were infected with T. gondii at postnatal day 33 (adolescent/juvenile) or 61 (adult). At 8weeks post-infection (wpi), pre-pulse inhibition of the acoustic startle (PPI) in mice administered MK-801 (0.1 and 0.3mg/kg) and amphetamine (5 and 10mg/kg) was assessed. Peripheral (anti-T. gondii, C1q-associated IgG and anti-GLUN2 antibodies) and central (C1q and Iba1) markers of the immune response were also evaluated. In addition, regional brain expression of N-methyl-d-aspartate receptor (NMDAR) subunits (GLUN1 and GLUN2A), glutamatergic (vGLUT1, PSD95) and GABAergic (GAD67) markers, and monoamines (DA, NE, 5-HT) and their metabolites were measured. RESULTS Juvenile and adult infected mice exhibited opposite effects of MK-801 on PPI, with decreased PPI in juveniles and increased PPI in adults. There was a significantly greater elevation of GLUN2 autoantibodies in juvenile-compared to adult-infected mice. In addition, age-dependent differences were found in regional expression of NMDAR subunits and markers of glutamatergic, GABAergic, and monoaminergic systems. Activated microglia and C1q elevations were found in both juvenile- and adult-T. gondii infected mice. CONCLUSIONS Our study demonstrates that the age at first exposure to T. gondii is an important factor in shaping distinct behavioral and neurobiological abnormalities. Elevation in GLUN2 autoantibodies or complement protein C1q may be a potential underlying mechanism. A better understanding of these age-related differences may lead to more efficient treatments of behavioral disorders associated with T. gondii infection.
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Affiliation(s)
- Geetha Kannan
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA.
| | - Joshua A Crawford
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA
| | - ChunXia Yang
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA
| | - Kristin L Gressitt
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Chinezimuzo Ihenatu
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Irina N Krasnova
- Molecular Neuropsychiatry Research Branch, National Institute on Drug Abuse, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MD 21224, USA
| | - Jean Lud Cadet
- Molecular Neuropsychiatry Research Branch, National Institute on Drug Abuse, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MD 21224, USA
| | - Robert H Yolken
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Emily G Severance
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Mikhail V Pletnikov
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA; Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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20
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Ayhan Y, McFarland R, Pletnikov MV. Animal models of gene-environment interaction in schizophrenia: A dimensional perspective. Prog Neurobiol 2015; 136:1-27. [PMID: 26510407 DOI: 10.1016/j.pneurobio.2015.10.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 09/07/2015] [Accepted: 10/22/2015] [Indexed: 12/12/2022]
Abstract
Schizophrenia has long been considered as a disorder with multifactorial origins. Recent discoveries have advanced our understanding of the genetic architecture of the disease. However, even with the increase of identified risk variants, heritability estimates suggest an important contribution of non-genetic factors. Various environmental risk factors have been proposed to play a role in the etiopathogenesis of schizophrenia. These include season of birth, maternal infections, obstetric complications, adverse events at early childhood, and drug abuse. Despite the progress in identification of genetic and environmental risk factors, we still have a limited understanding of the mechanisms whereby gene-environment interactions (G × E) operate in schizophrenia and psychoses at large. In this review we provide a critical analysis of current animal models of G × E relevant to psychotic disorders and propose that dimensional perspective will advance our understanding of the complex mechanisms of these disorders.
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Affiliation(s)
- Yavuz Ayhan
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA; Hacettepe University Faculty of Medicine, Department of Psychiatry, Turkey
| | - Ross McFarland
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA; Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, USA
| | - Mikhail V Pletnikov
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA; Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, USA; Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, USA; Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, USA.
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