1
|
Abstract
Peripheral inflammation could constitute a risk factor for AD. This review summarizes the research related to peripheral inflammation that appears to have a relationship with Alzheimer's disease. We find there are significant associations between AD and peripheral infection induced by various pathogens, including herpes simplex virus type 1, cytomegalovirus, Epstein-Barr virus, human immunodeficiency virus, severe acute respiratory syndrome coronavirus 2, Porphyromonas gingivalis, Helicobacter pylori, and Toxoplasma gondii. Chronic inflammatory diseases are also reported to contribute to the pathophysiology of AD. The mechanisms by which peripheral inflammation affects the pathophysiology of AD are complex. Pathogen-derived neurotoxic molecule composition, disrupted BBB, and dysfunctional neurogenesis may all play a role in peripheral inflammation, promoting the development of AD. Anti-pathogenic medications and anti-inflammatory treatments are reported to decrease the risk of AD. Studies that could improve understanding the associations between AD and peripheral inflammation are needed. If our assumption is correct, early intervention against inflammation may be a potential method of preventing and treating AD.
Collapse
Affiliation(s)
- Ziyuan Li
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| | - Hui Wang
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| | - Yafu Yin
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| |
Collapse
|
2
|
Sfera A, Rahman L, Zapata-Martín Del Campo CM, Kozlakidis Z. Long COVID as a Tauopathy: Of "Brain Fog" and "Fusogen Storms". Int J Mol Sci 2023; 24:12648. [PMID: 37628830 PMCID: PMC10454863 DOI: 10.3390/ijms241612648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/04/2023] [Accepted: 08/06/2023] [Indexed: 08/27/2023] Open
Abstract
Long COVID, also called post-acute sequelae of SARS-CoV-2, is characterized by a multitude of lingering symptoms, including impaired cognition, that can last for many months. This symptom, often called "brain fog", affects the life quality of numerous individuals, increasing medical complications as well as healthcare expenditures. The etiopathogenesis of SARS-CoV-2-induced cognitive deficit is unclear, but the most likely cause is chronic inflammation maintained by a viral remnant thriving in select body reservoirs. These viral sanctuaries are likely comprised of fused, senescent cells, including microglia and astrocytes, that the pathogen can convert into neurotoxic phenotypes. Moreover, as the enteric nervous system contains neurons and glia, the virus likely lingers in the gastrointestinal tract as well, accounting for the intestinal symptoms of long COVID. Fusogens are proteins that can overcome the repulsive forces between cell membranes, allowing the virus to coalesce with host cells and enter the cytoplasm. In the intracellular compartment, the pathogen hijacks the actin cytoskeleton, fusing host cells with each other and engendering pathological syncytia. Cell-cell fusion enables the virus to infect the healthy neighboring cells. We surmise that syncytia formation drives cognitive impairment by facilitating the "seeding" of hyperphosphorylated Tau, documented in COVID-19. In our previous work, we hypothesized that the SARS-CoV-2 virus induces premature endothelial senescence, increasing the permeability of the intestinal and blood-brain barrier. This enables the migration of gastrointestinal tract microbes and/or their components into the host circulation, eventually reaching the brain where they may induce cognitive dysfunction. For example, translocated lipopolysaccharides or microbial DNA can induce Tau hyperphosphorylation, likely accounting for memory problems. In this perspective article, we examine the pathogenetic mechanisms and potential biomarkers of long COVID, including microbial cell-free DNA, interleukin 22, and phosphorylated Tau, as well as the beneficial effect of transcutaneous vagal nerve stimulation.
Collapse
Affiliation(s)
- Adonis Sfera
- Paton State Hospital, 3102 Highland Ave, Patton, CA 92369, USA
- School of Behavioral Health, Loma Linda University, 11139 Anderson St., Loma Linda, CA 92350, USA
- Department of Psychiatry, University of California, Riverside 900 University Ave, Riverside, CA 92521, USA
| | - Leah Rahman
- Department of Neuroscience, University of Oregon, 222 Huestis Hall, Eugene, OR 97401, USA
| | | | - Zisis Kozlakidis
- International Agency for Research on Cancer, World Health Organization, 69000 Lyon, France
| |
Collapse
|
3
|
Diaz-Decaro J, Myers E, Mucha J, Neumann M, Lewandowski W, Kaczanowska M, Schmidt E, Natenshon A, Talarico C, Buck PO. A systematic literature review on the humanistic burden of cytomegalovirus. Curr Med Res Opin 2023; 39:739-750. [PMID: 36938652 DOI: 10.1080/03007995.2023.2191477] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/21/2023]
Abstract
OBJECTIVE Cytomegalovirus (CMV) infection is typically asymptomatic in healthy individuals; however, certain populations are vulnerable to infection and may develop serious sequelae. CMV infection may also have a broad impact on humanistic outcomes, including patient health status and quality of life (QoL). We conducted a systematic literature review (SLR) to describe the global humanistic burden of CMV and congenital CMV (cCMV) infections across all age groups. METHODS Medline, Embase, and LILACS were searched to identify studies on humanistic outcomes following CMV infection, including health status/QoL and any outcomes in domains such as auditory, cognitive ability, developmental status, intelligence, language, memory, mental health, motor performance, social communication, speech, and vocabulary. The SLR included articles published from 2000-2020 and focused geographically on Australia, Europe, Israel, Japan, Latin America, and North America. RESULTS Sixty-three studies met the inclusion criteria. In general, individuals with symptomatic cCMV infection experience a greater burden of disease and more substantial impact on QoL versus those with asymptomatic cCMV infection. Children with hearing loss due to cCMV infection, both symptomatic and asymptomatic, showed improved auditory outcomes following cochlear implantation. Newborns, infants, and children with cCMV infections had worse cognitive outcomes in psychological development, sequential and simultaneous processing, phonological working memory, and attention control versus age-matched controls without cCMV infection. CMV infection was also associated with cognitive decline in elderly populations. CONCLUSIONS CMV infection can have substantial, lifelong, heterogenous impacts on humanistic outcomes, including health status and QoL, which should be considered when developing and implementing treatment and prevention strategies.
Collapse
Affiliation(s)
| | - Evan Myers
- Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, NC, USA
| | | | | | - Witold Lewandowski
- Certara, Inc., Krakow, Poland
- Certara, Inc., employee at the time of the study
| | | | | | | | - Carla Talarico
- Moderna, Inc., Cambridge, MA, USA
- Moderna, Inc., employee at the time of the study
| | | |
Collapse
|
4
|
Abstract
There is increasingly compelling evidence that microorganisms may play an etiological role in the emergence of mental illness in a subset of the population. Historically, most work has focused on the neurotrophic herpesviruses, herpes simplex virus type 1 (HSV-1), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) as well as the protozoan, Toxoplasma gondii. In this chapter, we provide an umbrella review of this literature and additionally highlight prospective studies that allow more mechanistic conclusions to be drawn. Next, we focus on clinical trials of anti-microbial medications for the treatment of psychiatric disorders. We critically evaluate six trials that tested the impact of anti-herpes medications on inflammatory outcomes in the context of a medical disorder, nine clinical trials utilizing anti-herpetic medications for the treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) or schizophrenia, and four clinical trials utilizing anti-parasitic medications for the treatment of schizophrenia. We then turn our attention to evidence for a gut dysbiosis and altered microbiome in psychiatric disorders, and the potential therapeutic effects of probiotics, including an analysis of more than 10 randomized controlled trials of probiotics in the context of schizophrenia, bipolar disorder (BD), and major depressive disorder (MDD).
Collapse
|
5
|
Zheng W, Benner EM, Bloom DC, Muralidaran V, Caldwell JK, Prabhudesai A, Piazza PA, Wood J, Kinchington PR, Nimgaonkar VL, D'Aiuto L. Variations in Aspects of Neural Precursor Cell Neurogenesis in a Human Model of HSV-1 Infection. Organogenesis 2022; 18:2055354. [PMID: 35384798 PMCID: PMC8993067 DOI: 10.1080/15476278.2022.2055354] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Encephalitis, the most significant of the central nervous system (CNS) diseases caused by Herpes simplex virus 1 (HSV-1), may have long-term sequelae in survivors treated with acyclovir, the cause of which is unclear. HSV-1 exhibits a tropism toward neurogenic niches in CNS enriched with neural precursor cells (NPCs), which play a pivotal role in neurogenesis. NPCs are susceptible to HSV-1. There is a paucity of information regarding the influence of HSV-1 on neurogenesis in humans. We investigated HSV-1 infection of NPCs from two individuals. Our results show (i) HSV-1 impairs, to different extents, the proliferation, self-renewing, and, to an even greater extent, migration of NPCs from these two subjects; (ii) The protective effect of the gold-standard antiherpetic drug acyclovir (ACV) varies with viral dose and is incomplete. It is also subject to differences in terms of efficacy of the NPCs derived from these two individuals. These results suggest that the effects of HSV-1 may have on aspects of NPC neurogenesis may vary among individuals, even in the presence of acyclovir, and this may contribute to the heterogeneity of cognitive sequelae across encephalitis survivors. Further analysis of NPC cell lines from a larger number of individuals is warranted.
Collapse
Affiliation(s)
- Wenxiao Zheng
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Second Xiangya Hospital, Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Emily M Benner
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - David C Bloom
- Department of Molecular Genetics & Microbiology, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Vaishali Muralidaran
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jill K Caldwell
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Anuya Prabhudesai
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Paolo A Piazza
- Department of Infectious Diseases and Microbiology, Pitt Graduate School Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Joel Wood
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Paul R Kinchington
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Molecular Microbiology and Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Vishwajit L Nimgaonkar
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Leonardo D'Aiuto
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| |
Collapse
|
6
|
Marques ETA, Demers M, D'Aiuto L, Castanha PMS, Yeung J, Wood JA, Chowdari KV, Zheng W, Yolken RH, Nimgaonkar VL. Herpesvirus Infections in the Human Brain: A Neural Cell Model of the Complement System Derived from Induced Pluripotent Stem Cells. Curr Top Behav Neurosci 2023; 61:243-64. [PMID: 36059003 DOI: 10.1007/7854_2022_383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
BACKGROUND Herpesviruses alter cognitive functions in humans following acute infections; progressive cognitive decline and dementia have also been suggested. It is important to understand the pathogenic mechanisms of such infections. The complement system - comprising functionally related proteins integral for systemic innate and adaptive immunity - is an important component of host responses. The complement system has specialized functions in the brain. Still, the dynamics of the brain complement system are still poorly understood. Many complement proteins have limited access to the brain from plasma, necessitating synthesis and specific regulation of expression in the brain; thus, complement protein synthesis, activation, regulation, and signaling should be investigated in human brain-relevant cellular models. Cells derived from human-induced pluripotent stem cells (hiPSCs) could enable tractable models. METHODS Human-induced pluripotent stem cells were differentiated into neuronal (hi-N) and microglial (hi-M) cells that were cultured with primary culture human astrocyte-like cells (ha-D). Gene expression analyses and complement protein levels were analyzed in mono- and co-cultures. RESULTS Transcript levels of complement proteins differ by cell type and co-culture conditions, with evidence for cellular crosstalk in co-cultures. Hi-N and hi-M cells have distinct patterns of expression of complement receptors, soluble factors, and regulatory proteins. hi-N cells produce complement factor 4 (C4) and factor B (FB), whereas hi-M cells produce complement factor 2 (C2) and complement factor 3 (C3). Thus, neither hi-N nor hi-M cells can form either of the C3-convertases - C4bC2a and C3bBb. However, when hi-N and hi-M cells are combined in co-cultures, both types of functional C3 convertase are produced, indicated by elevated levels of the cleaved C3 protein, C3a. CONCLUSIONS hiPSC-derived co-culture models can be used to study viral infection in the brain, particularly complement receptor and function in relation to cellular "crosstalk." The models could be refined to further investigate pathogenic mechanisms.
Collapse
|
7
|
Della Vecchia A, Marazziti D. Back to the Future: The Role of Infections in Psychopathology. Focus on OCD. Clin Neuropsychiatry 2022; 19:248-263. [PMID: 36101642 PMCID: PMC9442856 DOI: 10.36131/cnfioritieditore20220407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
OBJECTIVE Recently, there has been a resurgence of interest in the relationship between infections and psychopathology, given the increasing data on the neurotropism and neurological/psychiatric morbidity of the SARS-COV2 virus, responsible for the current worldwide pandemic. Although the majority of observations were those obtained in mood and schizophrenic disorders, a few data are also available on the presence of bacterial or viral infections in patients suffering from obsessive-compulsive disorder (OCD). Therefore, given the limited information, the present paper aimed at reviewing the most updated evidence of infections in neuropsychiatric disorders and their possible mechanisms of actions, with a narrow focus on microbes in OCD. METHOD This paper is a narrative review. The databases of PubMed, Scopus, Embase, PsycINFO and Google Scholar were accessed to research and collect English language papers published between 1 January 1980 and 31 December 2021. The data on PANDAS/PANS and those observed during severe brain infections were excluded. RESULTS Several pathogens have been associated with an increased risk to develop a broad spectrum of neuropsychiatric conditions, such as schizophrenia, mood disorders, autism, attention-deficit/hyperactivity disorder, anorexia nervosa, and post-traumatic stress disorder. Some evidence supported a possible role of infections also in the pathophysiology of OCD. Infections from Herpes simplex virus 1, Borna disease virus, Group A-Beta Hemolytic Streptococcus, Borrelia spp., and Toxoplasma gondii were actually found in patients with OCD. Although different mechanisms have been hypothesized, all would converge to trigger functional/structural alterations of specific circuits or immune processes, with cascade dysfunctions of several other systems. CONCLUSIONS Based on the current evidence, a possible contribution of different types of microbes has been proposed for different neuropsychiatric disorders including OCD. However, the currently available literature is meager and heterogeneous in terms of sample characteristics and methods used. Therefore, further studies are needed to better understand the impact of infectious agents in neuropsychiatric disorders. Our opinion is that deeper insights in this field might contribute to a better definition of biological underpinnings of specific clinical pictures, as well as to promote psychiatric precision medicine, with treatments based on altered pathological pathways of single patients. This might be particularly relevant in OCD, a disorder with a high proportion of patients who are resistant or do not respond to conventional therapeutic strategies.
Collapse
Affiliation(s)
- Alessandra Della Vecchia
- Section of Psychiatry, Department of Clinical and Experimental Medicine, University of Pisa, and
| | - Donatella Marazziti
- Section of Psychiatry, Department of Clinical and Experimental Medicine, University of Pisa, and, Saint Camillus International University of Health and Medical Sciences – UniCamillus, Rome, Italy
| |
Collapse
|
8
|
Andreou D, Jørgensen KN, Nerland S, Ueland T, Vaskinn A, Haukvik UK, Yolken RH, Andreassen OA, Agartz I. Herpes simplex virus 1 infection on grey matter and general intelligence in severe mental illness. Transl Psychiatry 2022; 12:276. [PMID: 35821107 PMCID: PMC9276804 DOI: 10.1038/s41398-022-02044-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 06/22/2022] [Accepted: 06/29/2022] [Indexed: 11/09/2022] Open
Abstract
Schizophrenia and bipolar disorder are severe mental illnesses (SMI) linked to both genetic and environmental factors. Herpes simplex virus 1 (HSV1) is a common neurotropic pathogen which after the primary infection establishes latency with periodic reactivations. We hypothesized that the latent HSV1 infection is associated with brain structural abnormalities and cognitive impairment, especially in SMI. We included 420 adult patients with SMI (schizophrenia or bipolar spectrum) and 481 healthy controls. Circulating HSV1 immunoglobulin G concentrations were measured with immunoassays. We measured the total grey matter volume (TGMV), cortical, subcortical, cerebellar and regional cortical volumes based on T1-weighted MRI scans processed in FreeSurfer v6.0.0. Intelligence quotient (IQ) was assessed with the Wechsler Abbreviated Scale of Intelligence. Seropositive patients had significantly smaller TGMV than seronegative patients (642 cm3 and 654 cm3, respectively; p = 0.019) and lower IQ (104 and 107, respectively; p = 0.018). No TGMV or IQ differences were found between seropositive and seronegative healthy controls. Post-hoc analysis showed that (a) in both schizophrenia and bipolar spectrum, seropositive patients had similarly smaller TGMV than seronegative patients, whereas the HSV1-IQ association was driven by the schizophrenia spectrum group, and (b) among all patients, seropositivity was associated with smaller total cortical (p = 0.016), but not subcortical or cerebellar grey matter volumes, and with smaller left caudal middle frontal, precentral, lingual, middle temporal and banks of superior temporal sulcus regional cortical grey matter volumes. The results of this cross-sectional study indicate that HSV1 may be an environmental factor associated with brain structural abnormalities and cognitive impairment in SMI.
Collapse
Affiliation(s)
- Dimitrios Andreou
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway. .,Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway. .,Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden.
| | - Kjetil Nordbø Jørgensen
- grid.5510.10000 0004 1936 8921Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway ,grid.413684.c0000 0004 0512 8628Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| | - Stener Nerland
- grid.5510.10000 0004 1936 8921Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway ,grid.413684.c0000 0004 0512 8628Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| | - Torill Ueland
- grid.55325.340000 0004 0389 8485Psychosis Research Section, Oslo University Hospital, Oslo, Norway ,grid.5510.10000 0004 1936 8921Department of Psychology, University of Oslo, Oslo, Norway ,grid.55325.340000 0004 0389 8485Norwegian Centre for Mental Disorders Research (NORMENT), Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
| | - Anja Vaskinn
- grid.5510.10000 0004 1936 8921Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway ,grid.55325.340000 0004 0389 8485Centre for Research and Education in Forensic Psychiatry, Oslo University Hospital, Oslo, Norway
| | - Unn K. Haukvik
- grid.5510.10000 0004 1936 8921Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway ,grid.55325.340000 0004 0389 8485Norwegian Centre for Mental Disorders Research (NORMENT), Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway ,grid.55325.340000 0004 0389 8485Centre for Research and Education in Forensic Psychiatry, Oslo University Hospital, Oslo, Norway
| | - Robert H. Yolken
- grid.21107.350000 0001 2171 9311Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Ole A. Andreassen
- grid.5510.10000 0004 1936 8921Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway ,grid.55325.340000 0004 0389 8485Norwegian Centre for Mental Disorders Research (NORMENT), Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
| | - Ingrid Agartz
- grid.5510.10000 0004 1936 8921Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway ,grid.413684.c0000 0004 0512 8628Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway ,grid.425979.40000 0001 2326 2191Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
| |
Collapse
|
9
|
Abstract
Cytomegalovirus (CMV) is a common herpesvirus that establishes lifelong latent infections and interacts extensively with the host immune system, potentially contributing to immune activation and inflammation. Given its proclivity for infecting the brain and its reactivation by inflammatory stimuli, CMV is well known for causing central nervous system complications in the immune-naïve (e.g., in utero) and in the immunocompromised (e.g., in neonates, individuals receiving transplants or cancer chemotherapy, or people living with HIV). However, its potentially pathogenic role in diseases that are characterized by more subtle immune dysregulation and inflammation such as psychiatric disorders is still a matter of debate. In this chapter, we briefly summarize the pathogenic role of CMV in immune-naïve and immunocompromised populations and then review the evidence (i.e., epidemiological studies, serological studies, postmortem studies, and recent neuroimaging studies) for a link between CMV infection and psychiatric disorders with a focus on mood disorders and schizophrenia. Finally, we discuss the potential mechanisms through which CMV may cause CNS dysfunction in the context of mental disorders and conclude with a summary of the current state of play as well as potential future research directions in this area.
Collapse
Affiliation(s)
- Haixia Zheng
- Laureate Institute for Brain Research, Tulsa, OK, USA.
| | - Jonathan Savitz
- Laureate Institute for Brain Research, Tulsa, OK, USA.,Oxley College of Health Sciences, The University of Tulsa, Tulsa, OK, USA
| |
Collapse
|
10
|
Yong SJ, Yong MH, Teoh SL, Soga T, Parhar I, Chew J, Lim WL. The Hippocampal Vulnerability to Herpes Simplex Virus Type I Infection: Relevance to Alzheimer's Disease and Memory Impairment. Front Cell Neurosci 2021; 15:695738. [PMID: 34483839 PMCID: PMC8414573 DOI: 10.3389/fncel.2021.695738] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 07/20/2021] [Indexed: 12/24/2022] Open
Abstract
Herpes simplex virus type 1 (HSV-1) as a possible infectious etiology in Alzheimer’s disease (AD) has been proposed since the 1980s. The accumulating research thus far continues to support the association and a possible causal role of HSV-1 in the development of AD. HSV-1 has been shown to induce neuropathological and behavioral changes of AD, such as amyloid-beta accumulation, tau hyperphosphorylation, as well as memory and learning impairments in experimental settings. However, a neuroanatomical standpoint of HSV-1 tropism in the brain has not been emphasized in detail. In this review, we propose that the hippocampal vulnerability to HSV-1 infection plays a part in the development of AD and amnestic mild cognitive impairment (aMCI). Henceforth, this review draws on human studies to bridge HSV-1 to hippocampal-related brain disorders, namely AD and aMCI/MCI. Next, experimental models and clinical observations supporting the neurotropism or predilection of HSV-1 to infect the hippocampus are examined. Following this, factors and mechanisms predisposing the hippocampus to HSV-1 infection are discussed. In brief, the hippocampus has high levels of viral cellular receptors, neural stem or progenitor cells (NSCs/NPCs), glucocorticoid receptors (GRs) and amyloid precursor protein (APP) that support HSV-1 infectivity, as well as inadequate antiviral immunity against HSV-1. Currently, the established diseases HSV-1 causes are mucocutaneous lesions and encephalitis; however, this review revises that HSV-1 may also induce and/or contribute to hippocampal-related brain disorders, especially AD and aMCI/MCI.
Collapse
Affiliation(s)
- Shin Jie Yong
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
| | - Min Hooi Yong
- Department of Psychology, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia.,Aging Health and Well-being Research Centre, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
| | - Seong Lin Teoh
- Department of Anatomy, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Tomoko Soga
- Jeffrey Cheah School of Medicine and Health Sciences, Brain Research Institute Monash Sunway, Monash University Malaysia, Subang Jaya, Malaysia
| | - Ishwar Parhar
- Jeffrey Cheah School of Medicine and Health Sciences, Brain Research Institute Monash Sunway, Monash University Malaysia, Subang Jaya, Malaysia
| | - Jactty Chew
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
| | - Wei Ling Lim
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia.,Aging Health and Well-being Research Centre, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
| |
Collapse
|
11
|
Affiliation(s)
- Konasale M Prasad
- Department of Psychiatry and Bioengineering, University of Pittsburgh School of Medicine and Swanson School of Engineering, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, PA 15213, USA.
| |
Collapse
|
12
|
Andreou D, Jørgensen KN, Wortinger LA, Engen K, Vaskinn A, Ueland T, Yolken RH, Andreassen OA, Agartz I. Cytomegalovirus infection and IQ in patients with severe mental illness and healthy individuals. Psychiatry Res 2021; 300:113929. [PMID: 33866186 DOI: 10.1016/j.psychres.2021.113929] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 04/05/2021] [Indexed: 11/26/2022]
Abstract
Cytomegalovirus (CMV) infection in immunocompetent adults is usually asymptomatic, but results in lifelong latency. Infection occurring congenitally or in immunodeficiency can lead to cognitive impairment. We aimed to investigate the associations between CMV exposure and intelligence quotient (IQ) in patients with schizophrenia spectrum disorders (SZS), bipolar spectrum disorders (BDS) and healthy controls (HC). CMV immunoglobulin G antibody concentrations were measured by immunoassay and expressed as dichotomous measures (seropositive/CMV+ vs. seronegative/CMV-). Based on a significant CMV-by-diagnosis-by-sex interaction on IQ, we investigated main and interaction effects of CMV and sex on IQ in each diagnostic category. Significant CMV-by-sex interactions were found in patient groups. In SZS, CMV+ female patients (n = 50) had significantly lower IQ than CMV- female patients (n = 33), whereas CMV+ (n = 48) and CMV- (n = 45) male patients did not differ in IQ. In BDS, CMV+ (n = 49) and CMV- (n = 37) female patients did not differ in IQ, whereas CMV+ male patients (n = 33) had significantly higher IQ than CMV- male patients (n = 32). Among HC, CMV+ (n = 138) and CMV- (n = 118) male participants as well as CMV+ (n = 125) and CMV- (n = 93) female participants did not differ in IQ. Our findings suggest that CMV exposure may affect IQ in patients with severe mental illness but not HC.
Collapse
Affiliation(s)
- Dimitrios Andreou
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden; 1st Department of Psychiatry, National and Kapodistrian University of Athens, Athens, Greece; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway.
| | - Kjetil Nordbø Jørgensen
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| | - Laura A Wortinger
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| | - Kristine Engen
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| | - Anja Vaskinn
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Psychosis Research Section, Oslo University Hospital, Oslo, Norway
| | - Torill Ueland
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Psychosis Research Section, Oslo University Hospital, Oslo, Norway; Department of Psychology, University of Oslo, Oslo, Norway
| | - Robert H Yolken
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Ole A Andreassen
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Norwegian Centre for Mental Disorders Research (NORMENT), Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
| | - Ingrid Agartz
- Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| |
Collapse
|
13
|
Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disease associated with the overproduction and accumulation of amyloid-β peptide and hyperphosphorylation of tau proteins in the brain. Despite extensive research on the amyloid-based mechanism of AD pathogenesis, the underlying cause of AD is not fully understood. No disease-modifying therapies currently exist, and numerous clinical trials have failed to demonstrate any benefits. The recent discovery that the amyloid-β peptide has antimicrobial activities supports the possibility of an infectious aetiology of AD and suggests that amyloid-β plaque formation might be induced by infection. AD patients have a weakened blood-brain barrier and immune system and are thus at elevated risk of microbial infections. Such infections can cause chronic neuroinflammation, production of the antimicrobial amyloid-β peptide, and neurodegeneration. Various pathogens, including viruses, bacteria, fungi, and parasites have been associated with AD. Most research in this area has focused on individual pathogens, with herpesviruses and periodontal bacteria being most frequently implicated. The purpose of this review is to highlight the potential role of multi-pathogen infections in AD. Recognition of the potential coexistence of multiple pathogens and biofilms in AD's aetiology may stimulate the development of novel approaches to its diagnosis and treatment. Multiple diagnostic tests could be applied simultaneously to detect major pathogens, followed by anti-microbial treatment using antiviral, antibacterial, antifungal, and anti-biofilm agents.
Collapse
Affiliation(s)
- Dana Vigasova
- International Clinical Research Center, St. Anne’s University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Michal Nemergut
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Barbora Liskova
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jiri Damborsky
- International Clinical Research Center, St. Anne’s University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| |
Collapse
|
14
|
Dickerson F, Schroeder JR, Nimgaonkar V, Gold J, Yolken R. The association between exposure to herpes simplex virus type 1 (HSV-1) and cognitive functioning in schizophrenia: A meta-analysis. Psychiatry Res 2020; 291:113157. [PMID: 32593064 DOI: 10.1016/j.psychres.2020.113157] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 05/26/2020] [Accepted: 05/29/2020] [Indexed: 12/12/2022]
Abstract
Cognitive deficits are characteristic of schizophrenia but their etiology is not understood. Previous studies show an association between viral exposures and cognitive impairment. This meta-analysis was undertaken to determine the relationship of herpes simplex virus type 1 (HSV-1) exposure and cognitive functioning in schizophrenia. A systematic search was performed for studies comparing the cognitive functioning of HSV-1 seropositive vs. seronegative persons with schizophrenia. The primary outcome was the standardized mean difference (SMD) in composite cognitive score using Hedges' g. Secondary outcomes were SMDs in 9cognitive domains. Study heterogeneity was estimated using the I2 index and formal tests of heterogeneity using Cochran's Q. In a sample of 3516 individuals from 9 studies the SMD was negative for the composite score and all 9 domains indicating a significant deficit for seropositive individuals in 8 domains. The SMDs ranged from -0.11 (Working Memory) to -0.36 (Visual Spatial). Cochran's Q test indicated heterogeneity for one domain. The I2 index of heterogeneity was in the low -moderate range for all but one domain. Exposure to HSV-1 is associated with decreased cognitive functioning in schizophrenia. An increased understanding of HSV-1 exposure might lead to improved methods for the prevention and treatment of cognitive deficits in schizophrenia.
Collapse
Affiliation(s)
- Faith Dickerson
- Sheppard Pratt Health System, 6501 North Charles Street, Baltimore, MD 21204.
| | | | - Viswajit Nimgaonkar
- Department of Psychiatry, University of Pittsburgh, 3811 O'Hara St., Pittsburgh, PA 15213
| | - James Gold
- Maryland Psychiatric Research Center, 55 Wade Ave, Catonsville, MD 21228
| | - Robert Yolken
- Johns Hopkins School of Medicine, 600 North Wolfe St., Baltimore, MD 21287
| |
Collapse
|
15
|
Kamer AR, Craig RG, Niederman R, Fortea J, de Leon MJ. Periodontal disease as a possible cause for Alzheimer's disease. Periodontol 2000 2020; 83:242-271. [PMID: 32385876 DOI: 10.1111/prd.12327] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 06/23/2019] [Indexed: 12/13/2022]
Abstract
Approximately 47 million people worldwide have been diagnosed with dementia, 60%-80% of whom have dementia of the Alzheimer's disease type. Unfortunately, there is no cure in sight. Defining modifiable risk factors for Alzheimer's disease may have a significant impact on its prevalence. An increasing body of evidence suggests that chronic inflammation and microbial dysbiosis are risk factors for Alzheimer's disease. Periodontal disease is a chronic inflammatory disease that develops in response to response to microbial dysbiosis. Many studies have shown an association between periodontal disease and Alzheimer's disease. The intent of this paper was to review the existing literature and determine, using the Bradford Hill criteria, whether periodontal disease is causally related to Alzheimer's disease.
Collapse
Affiliation(s)
- Angela R Kamer
- Department of Periodontology and Implant Dentistry, New York University, College of Dentistry, New York, New York, USA
| | - Ronald G Craig
- Department of Periodontology and Implant Dentistry, New York University, College of Dentistry, New York, New York, USA.,Department of Basic Sciences and Craniofacial Biology, New York University, College of Dentistry, New York, New York, USA
| | - Richard Niederman
- Department of Epidemiology and Health Promotion, New York University, College of Dentistry, New York, New York, USA
| | - Juan Fortea
- Alzheimer Down Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau- Biomedical Research Institute Sant Pau- Universitat Autònoma de Barcelona and Barcelona Down Medical Center, Fundació Catalana Síndrome de Down, Barcelona, Spain.,Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain
| | - Mony J de Leon
- Department of Radiology, Brain Health Imaging Institute, Weill Cornell Medicine, New York, New York, USA
| |
Collapse
|
16
|
Fülöp T, Munawara U, Larbi A, Desroches M, Rodrigues S, Catanzaro M, Guidolin A, Khalil A, Bernier F, Barron AE, Hirokawa K, Beauregard PB, Dumoulin D, Bellenger JP, Witkowski JM, Frost E. Targeting Infectious Agents as a Therapeutic Strategy in Alzheimer's Disease. CNS Drugs 2020; 34:673-695. [PMID: 32458360 PMCID: PMC9020372 DOI: 10.1007/s40263-020-00737-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease (AD) is the most prevalent dementia in the world. Its cause(s) are presently largely unknown. The most common explanation for AD, now, is the amyloid cascade hypothesis, which states that the cause of AD is senile plaque formation by the amyloid β peptide, and the formation of neurofibrillary tangles by hyperphosphorylated tau. A second, burgeoning theory by which to explain AD is based on the infection hypothesis. Much experimental and epidemiological data support the involvement of infections in the development of dementia. According to this mechanism, the infection either directly or via microbial virulence factors precedes the formation of amyloid β plaques. The amyloid β peptide, possessing antimicrobial properties, may be beneficial at an early stage of AD, but becomes detrimental with the progression of the disease, concomitantly with alterations to the innate immune system at both the peripheral and central levels. Infection results in neuroinflammation, leading to, and sustained by, systemic inflammation, causing eventual neurodegeneration, and the senescence of the immune cells. The sources of AD-involved microbes are various body microbiome communities from the gut, mouth, nose, and skin. The infection hypothesis of AD opens a vista to new therapeutic approaches, either by treating the infection itself or modulating the immune system, its senescence, or the body's metabolism, either separately, in parallel, or in a multi-step way.
Collapse
Affiliation(s)
- Tamàs Fülöp
- Geriatric Division, Department of Medicine, Faculty of Medicine and Health Sciences, Research Center on Aging, University of Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada.
| | - Usma Munawara
- Geriatric Division, Department of Medicine, Faculty of Medicine and Health Sciences, Research Center on Aging, University of Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada
| | - Anis Larbi
- Singapore Immunology Network (SIgN), Agency for Science Technology and Research (A*STAR), Immunos Building, Biopolis, Singapore, Singapore
- Department of Biology, Faculty of Science, University Tunis El Manar, Tunis, Tunisia
| | - Mathieu Desroches
- MathNeuro Team, Inria Sophia Antipolis Méditerranée, Valbonne, France
- Université Côte d'Azur, Nice, France
| | - Serafim Rodrigues
- Ikerbasque, The Basque Foundation for Science, Bilbao, Spain
- BCAM, The Basque Center for Applied Mathematics, Bilbao, Spain
| | - Michele Catanzaro
- Geriatric Division, Department of Medicine, Faculty of Medicine and Health Sciences, Research Center on Aging, University of Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada
- Department of Drug Sciences, University of Pavia, Pavia, Italy
| | - Andrea Guidolin
- BCAM, The Basque Center for Applied Mathematics, Bilbao, Spain
| | - Abdelouahed Khalil
- Geriatric Division, Department of Medicine, Faculty of Medicine and Health Sciences, Research Center on Aging, University of Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada
| | - François Bernier
- Next Generation Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
| | - Annelise E Barron
- Department of Bioengineering, Stanford School of Medicine, Stanford, CA, USA
| | - Katsuiku Hirokawa
- Department of Pathology, Institute of Health and Life Science, Tokyo and Nito-memory Nakanosogo Hospital, Tokyo Med. Dent. University, Tokyo, Japan
| | - Pascale B Beauregard
- Department of Biology, Faculty of Sciences, University of Sherbrooke, Sherbrooke, QC, Canada
| | - David Dumoulin
- Department of Biology, Faculty of Sciences, University of Sherbrooke, Sherbrooke, QC, Canada
| | - Jean-Philippe Bellenger
- Department of Chemistry, Faculty of Sciences, University of Sherbrooke, Sherbrooke, QC, Canada
| | - Jacek M Witkowski
- Department of Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | - Eric Frost
- Department of Microbiology and Infectious diseases, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC, Canada
| |
Collapse
|
17
|
Devanand DP, Andrews H, Kreisl WC, Razlighi Q, Gershon A, Stern Y, Mintz A, Wisniewski T, Acosta E, Pollina J, Katsikoumbas M, Bell KL, Pelton GH, Deliyannides D, Prasad KM, Huey ED. Antiviral therapy: Valacyclovir Treatment of Alzheimer's Disease (VALAD) Trial: protocol for a randomised, double-blind,placebo-controlled, treatment trial. BMJ Open 2020; 10:e032112. [PMID: 32034019 PMCID: PMC7045215 DOI: 10.1136/bmjopen-2019-032112] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 10/16/2019] [Accepted: 11/26/2019] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION After infection, herpes simplex virus-1 (HSV1) becomes latent in the trigeminal ganglion and can enter the brain via retrograde axonal transport. Recurrent reactivation of HSV1 may lead to neurodegeneration and Alzheimer's disease (AD) pathology. HSV1 (oral herpes) and HSV2 (genital herpes) can trigger amyloid beta-protein (Aβ) aggregation and HSV1 DNA is common in amyloid plaques. Anti-HSV drugs reduce Aβ and phosphorylated tau accumulation in cell-culture models. Cognitive impairment is greater in patients with HSV seropositive, and antiviral drugs show robust efficacy against peripheral HSV infection. Recent studies of electronic health records databases demonstrate that HSV infections increase dementia risk, and that antiviral medication treatment reduces this risk. The generic antiviral drug valacyclovir was superior to placebo in improving memory in a schizophrenia pilot trial but has not been tested in AD. METHODS AND ANALYSIS In patients with mild AD who test positive for HSV1 or HSV2 serum antibodies, valacyclovir, repurposed as an anti-AD drug, will be compared with placebo (lactose pills) in 130 patients (65 valacyclovir and 65 placebo) in a randomised, double-blind, 78-week phase II proof-of-concept trial. Patients on valacyclovir, dose-titrated from 2 g to a targeted oral dose of 4 g daily, compared with placebo, are hypothesised to show smaller cognitive and functional decline, and, using 18F-Florbetapir positron emission tomography (PET) and 18F-MK-6240 PET imaging, to show less amyloid and tau accumulation, respectively. In the lumbar puncture subsample, cerebrospinal fluid acyclovir will be assayed to assess central nervous system valacyclovir penetration. ETHICS AND DISSEMINATION The trial is being overseen by the New York State Psychiatric Institute Institutional Review Board (protocol 7537), the National Institute on Ageing, and the Data Safety Monitoring Board. Written informed consent is obtained for all subjects. Results will be disseminated via publication, clinicaltrials.gov, media and conferences. TRIAL REGISTRATION NUMBER ClinicalTrials.gov identifier (NCT03282916) Pre-results.
Collapse
Affiliation(s)
- D P Devanand
- Department of Psychiatry, Columbia University, New York, New York, USA
- Division of Geriatric Psychiatry, New York State Psychiatric Institute, New York, New York, USA
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, USA
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | - Howard Andrews
- Department of Psychiatry, Columbia University, New York, New York, USA
- Division of Geriatric Psychiatry, New York State Psychiatric Institute, New York, New York, USA
- Department of Biostatistics, Columbia University Medical Center, New York, New York, USA
| | - William C Kreisl
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, USA
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | - Qolamreza Razlighi
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, USA
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | - Anne Gershon
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | - Yaakov Stern
- Department of Psychiatry, Columbia University, New York, New York, USA
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, USA
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | - Akiva Mintz
- Department of Radiology, Columbia University Medical Center, New York, New York, USA
| | - Thomas Wisniewski
- Center for Cognitive Neurology, Departments of Neurology, New York University Medical Center, New York, New York, USA
| | - Edward Acosta
- Department of Pharmacology, University of Alabama, Tuscaloosa, Alabama, USA
| | - Julianna Pollina
- Department of Psychiatry, Columbia University, New York, New York, USA
- Division of Geriatric Psychiatry, New York State Psychiatric Institute, New York, New York, USA
| | - Mariasofia Katsikoumbas
- Department of Psychiatry, Columbia University, New York, New York, USA
- Division of Geriatric Psychiatry, New York State Psychiatric Institute, New York, New York, USA
| | - Karen L Bell
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, USA
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | - Gregory H Pelton
- Department of Psychiatry, Columbia University, New York, New York, USA
- Division of Geriatric Psychiatry, New York State Psychiatric Institute, New York, New York, USA
| | - Deborah Deliyannides
- Department of Psychiatry, Columbia University, New York, New York, USA
- Division of Geriatric Psychiatry, New York State Psychiatric Institute, New York, New York, USA
| | - K M Prasad
- Departments of Psychiatry and Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, Pennsylvania, USA
| | - Edward D Huey
- Department of Psychiatry, Columbia University, New York, New York, USA
- Division of Geriatric Psychiatry, New York State Psychiatric Institute, New York, New York, USA
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, USA
- Department of Neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University College of Physicians and Surgeons, New York, New York, USA
| |
Collapse
|
18
|
Kang WS, Kim SK, Park HJ. Association of the Promoter Haplotype of IFN-γ-Inducible Protein 16 Gene with Schizophrenia in a Korean Population. Psychiatry Investig 2020; 17:140-146. [PMID: 32046472 PMCID: PMC7047005 DOI: 10.30773/pi.2019.0175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/18/2019] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Viral infections play an important role in the development of schizophrenia, inducing the faulty immunological responses and aberrant inflammation. IFN-γ-inducible protein 16 (IFI16) is an immunological DNA sensor against viral infections, triggering the inflammatory responses. In this study, we investigated an association between putative promoter single nucleotide polymorphisms (SNPs) and haplotypes of IFI16 and schizophrenia. METHODS A total of 280 schizophrenia patients and 427 control subjects were recruited in this study. We genotyped three promoter SNPs (rs1465175, rs3754464, rs1417806) using direct sequencing. Associations of SNPs and haplotypes of IFI16 with schizophrenia were analyzed. The promoter activities on the haplotypes of IFI16 were measured. RESULTS The T allele of rs1465175 and the C allele of rs1417806 were protectively associated with schizophrenia (p=0.021 on rs1465175; p=0.016 on rs1417806), whereas the G allele of rs3754464 was associated with an increased risk of schizophrenia (p=0.019). In haplotype analysis, a significant association between the GGA haplotype and schizophrenia was shown (p=0.013). Moreover, we found that the GGA haplotype elevated the promoter activity compared to the GAA haplotype, whereas the TAC haplotype reduced that. CONCLUSION The promoter SNPs and haplotypes of IFI16 may contribute to the susceptibility of schizophrenia, affecting the promoter activity of IFI16.
Collapse
Affiliation(s)
- Won Sub Kang
- Department of Neuropsychiatry, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Su Kang Kim
- Department of Biomedical Laboratory Science, Catholic Kwandong University, Gangneung, Republic of Korea
| | - Hae Jeong Park
- Department of Pharmacology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| |
Collapse
|
19
|
Nimgaonkar VL, Bhatia T, Mansour A, Wesesky MA, Deshpande S. Herpes Simplex Virus Type-1 Infection: Associations with Inflammation and Cognitive Aging in Relation to Schizophrenia. Curr Top Behav Neurosci 2020; 44:125-139. [PMID: 31049838 DOI: 10.1007/7854_2018_86] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Most persons experience cognitive decline as they grow older. The term "cognitive aging," coined to describe milder varieties of cognitive decline, is likely to be due to multiple causes. Persistent or repeated infections of the central nervous system (whether subclinical or diagnosable) can cause damage to neurons directly or indirectly through inflammation resulting in incremental neuronal damage, thus eroding cognitive reserve. This possibility has not been considered widely. We evaluated the data linking persistent infection with herpes simplex virus type 1 (HSV-1) and cognitive aging by applying the Bradford Hill criteria. Despite inherent problems in establishing causal relations for chronic disorders, our analyses suggest plausible links. These studies are pertinent for patients with schizophrenia, who are particularly vulnerable due to disorder-related cognitive impairment. Further investigations are warranted to test a causal hypothesis, particularly prospective studies and intervention studies.
Collapse
Affiliation(s)
- Vishwajit L Nimgaonkar
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- Department of Human Genetics, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Triptish Bhatia
- Training Program for Psychiatric Genetics in India, Post-graduate Institute for Medical Education and Research, Dr Ram Manohar Lohia Hospital, Delhi, India
| | - Abdelaziz Mansour
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Maribeth A Wesesky
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Smita Deshpande
- Post-graduate Institute for Medical Education and Research, Dr Ram Manohar Lohia Hospital, New Delhi, India
| |
Collapse
|
20
|
Meshreky KM, Wood J, Chowdari KV, Hall MH, Wilckens KA, Yolken R, Buysse DJ, Nimgaonkar VL. Infection with Herpes Simplex virus type 1 (HSV-1) and sleep: The dog that did not bark. Psychiatry Res 2019; 280:112502. [PMID: 31382180 PMCID: PMC7265549 DOI: 10.1016/j.psychres.2019.112502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 07/30/2019] [Accepted: 07/31/2019] [Indexed: 10/26/2022]
Abstract
Persistent infection with Herpes Simplex viruses (HSV) and other brain infections is consistently associated with cognitive impairment. These infections can also affect sleep. Thus, sleep abnormalities could explain the cognitive dysfunction. We investigated the association between sleep variables and persistent HSV-1, HSV-2, cytomegalovirus (CMV) and Toxoplasma gondii (Tox) infections. Sleep data were collected from older adults with or without insomnia (N = 311, total); a subset completed polysomnographic and actigraphy studies (N = 145). No significant associations were found between the infections and insomnia or the remaining sleep variables following corrections for multiple comparisons. Sleep dysfunction is unlikely to explain the infection-related cognitive dysfunction.
Collapse
Affiliation(s)
| | - Joel Wood
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Kodavali V Chowdari
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Martica H Hall
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Kristine A. Wilckens
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Robert Yolken
- Stanley Laboratory of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Daniel J. Buysse
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Vishwajit L Nimgaonkar
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, United States.
| |
Collapse
|
21
|
Abstract
People with schizophrenia and primary negative symptoms (deficit schizophrenia) differ from those without such symptoms (nondeficit schizophrenia) on risk factors, course of illness, other signs and symptoms, treatment response, and biological correlates. These differences suggest that the 2 groups may also have developmental differences. A previous study found that people with schizophrenia have a wider palate than comparison subjects. We tested the hypothesis that those with deficit and nondeficit schizophrenia would differ on palate width. A dentist made blinded measurements of palate shape in deficit (N = 21) and nondeficit (N = 25) patients and control subjects (N = 127), matched for age and gender. The deficit group had significantly wider palates than either nondeficit or control subjects (respective means [standard deviation] 37.5 [3.9], 33.7 [3.1], and 34.0 [2.9]; P < .001 for both deficit/nondeficit and deficit/control comparisons, respective effect sizes 1.08 and 1.01). The nondeficit/control difference in width was not significant (P = .83), and there were no significant group differences in length or depth. The power to detect a nondeficit/control difference in width equal in size to that of the deficit/control difference in width (3.5 mm) was 0.99 and 0.92 for a 2.0-mm difference. This difference in palate width may reflect a divergence in development between deficit and nondeficit patients that occurs by the early second trimester and is consistent with the hypothesis that deficit schizophrenia is a separate disease within the syndrome of schizophrenia.
Collapse
Affiliation(s)
- Brian Kirkpatrick
- Department of Psychiatry and Behavioral Sciences, University of Nevada, Reno School of Medicine, Reno, Nevada,To whom correspondence should be addressed; tel: 775-682-8455, fax: 775-784-1428, e-mail:
| | - Özlem Gürbüz Oflezer
- Department of Prosthetic Dentistry, Ministry of Health, Istanbul Bahcelievler Oral and Dental Hospital, Istanbul, Turkey
| | - Mehtap Delice Arslan
- Department of Psychiatry, Bakirkoy Research and Training Hospital for Psychiatry, Neurology and Neurosurgery, Istanbul, Turkey
| | - Gary Hack
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, Maryland
| | - Emilio Fernandez-Egea
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK,Department of Psychiatry and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK,Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Barcelona, Spain
| |
Collapse
|
22
|
Breier A, Buchanan RW, D'Souza D, Nuechterlein K, Marder S, Dunn W, Preskorn S, Macaluso M, Wurfel B, Maguire G, Kakar R, Highum D, Hoffmeyer D, Coskinas E, Litman R, Vohs JL, Radnovich A, Francis MM, Metzler E, Visco A, Mehdiyoun N, Yang Z, Zhang Y, Yolken RH, Dickerson FB. Herpes simplex virus 1 infection and valacyclovir treatment in schizophrenia: Results from the VISTA study. Schizophr Res 2019; 206:291-299. [PMID: 30478008 DOI: 10.1016/j.schres.2018.11.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/02/2018] [Accepted: 11/03/2018] [Indexed: 10/27/2022]
Abstract
BACKGROUND Several studies have implicated herpes simplex virus-type 1 (HSV-1) in the pathophysiology of schizophrenia. A recent trial demonstrated that the anti-viral medication valacylovir, which prevents replication of activated HSV-1, improved selected cognitive deficits in people with schizophrenia. In this study, we examined demographic and illness related differences between HSV-1 positive versus HSV-1 negative subjects with early phase schizophrenia and attempted to replicate the previous valacyclovir treatment results in this population. METHODS 170 subjects with schizophrenia (HSV-1 positive N = 70; HSV-1 negative N = 96) from 12 US sites participated in the HSV-1 positive versus negative comparisons, and were randomized 1:1 to valacyclovir (1.5 g BID) or placebo for a 16-week, double-blind efficacy trial. The primary endpoints were working and verbal memory. RESULTS The HSV-1 positive group, as compared to the HSV-1 negative group, were older (p < 0.001) with fewer males (p = 0.003), and had a longer duration of illness (p = 0.008), more positive symptoms (p = 0.013), poorer quality of life (p = 0.034) and more impairment on the letter-number sequencing test, which is a measure of working memory (p = 0.045). Valacyclovir failed to significantly improve any of the cognitive indices, symptom or functioning measures. CONCLUSIONS HSV-1 sero-positivity appears to be a marker of a subgroup with a more severe form of schizophrenia. Valacyclovir was not efficacious in the study, perhaps because the herpes virus was in the dormant, non-activated state and therefore non-responsive to valacyclovir effects. ClinicalTrials.gov Identifier: NCT02008773.
Collapse
Affiliation(s)
- Alan Breier
- Indiana University School of Medicine, Indianapolis, IN, United States of America.
| | - Robert W Buchanan
- Maryland Psychiatric Research Center, University of Maryland, Baltimore, MD, United States of America
| | - Deepak D'Souza
- Yale University School of Medicine, New Haven, CT, United States of America
| | | | - Stephen Marder
- Semel Institute, UCLA, Los Angeles, CA, United States of America
| | - Walter Dunn
- Semel Institute, UCLA, Los Angeles, CA, United States of America
| | - Sheldon Preskorn
- Kansas University School of Medicine, Wichita, KS, United States of America
| | - Matthew Macaluso
- Kansas University School of Medicine, Wichita, KS, United States of America
| | - Brent Wurfel
- Laureate Institute for Brain Research, KS, United States of America
| | - Gerald Maguire
- University of California, Riverside, CA, United States of America
| | - Rishi Kakar
- Segal Institute for Clinical Research, United States of America
| | - Diane Highum
- CITrials, Bellflower, CA, United States of America
| | | | | | | | - Jenifer L Vohs
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Alexander Radnovich
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Michael M Francis
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Emmalee Metzler
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Andrew Visco
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Nicole Mehdiyoun
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Ziyi Yang
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Ying Zhang
- Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Robert H Yolken
- Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Faith B Dickerson
- Sheppard Pratt Health System, Baltimore, MD, United States of America
| |
Collapse
|
23
|
Abstract
The study of microorganisms such as bacteria, viruses, archaea, fungi, and protozoa in the context of psychiatric disorders may be surprising to some. This intersection of disciplines, however, has a rich history and is currently revitalized by newfound functions of the microbiome and the gut-brain axis in human diseases. Schizophrenia, in particular, fits this model as a disorder with gene and environmental roots that may be anchored in the immune system. In this context, the combination of a precisely timed pathogen exposure in a person with genetically encoded altered immunity may have especially destructive consequences for the central nervous system (CNS). Furthermore, significant components of immunity, such as the development of the immune response and the concept of immune tolerance, are largely dictated by the commensal residents of the microbiome. When this community of microbes is imbalanced, perhaps as the result of a pathogen invasion, stress, or immune gene deficiency, a pathological cycle of localized inflammation, endothelial barrier compromise, translocation of gut-derived products, and systemic inflammation may ensue. If these pathologies enable access of gut and microbial metabolites and immune molecules to the CNS across the blood-brain barrier (BBB), and studies of the gut-brain axis support this hypothesis, a worsening of cognitive deficits and psychiatric symptoms is predicted to occur in susceptible individuals with schizophrenia. In this chapter, we review the role of microbes in various stages of this model and how these organisms may contribute to documented phenotypes of schizophrenia. An increased understanding of the role of pathogens and the microbiome in psychiatric disorders will better guide the development of microbial and immune-based therapeutics for disease prevention and treatment.
Collapse
Affiliation(s)
- Golam M. Khandaker
- grid.5335.00000000121885934Department of Psychiatry, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | - Urs Meyer
- grid.5801.c0000 0001 2156 2780Verhaltensneurobiologie, ETH Zürich, Schwerzenbach, Switzerland
| | - Peter B. Jones
- grid.5335.00000000121885934Department of Psychiatry, University of Cambridge School of Clinical Medicine, Cambridge, UK
| |
Collapse
|
24
|
Lövheim H, Norman T, Weidung B, Olsson J, Josefsson M, Adolfsson R, Nyberg L, Elgh F. Herpes Simplex Virus, APOE ɛ4, and Cognitive Decline in Old Age: Results from the Betula Cohort Study. J Alzheimers Dis 2019; 67:211-220. [DOI: 10.3233/jad-171162] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Hugo Lövheim
- Department of Community Medicine and Rehabilitation, Geriatric Medicine, Umeå University, Umeå, Sweden
| | - Tove Norman
- Department of Community Medicine and Rehabilitation, Geriatric Medicine, Umeå University, Umeå, Sweden
| | - Bodil Weidung
- Department of Community Medicine and Rehabilitation, Geriatric Medicine, Umeå University, Umeå, Sweden
- Department of Public Health and Caring Sciences, Geriatric Medicine, Uppsala University, Uppsala, Sweden
| | - Jan Olsson
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
| | - Maria Josefsson
- Centre for Demographic and Ageing Research, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Rolf Adolfsson
- Department of Clinical Sciences, Psychiatry, Umeå University, Umeå, Sweden
| | - Lars Nyberg
- Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Department of Integrative Medical Biology, Umeå University, Umeå, Sweden
| | - Fredrik Elgh
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
| |
Collapse
|
25
|
Abstract
Typical and atypical antipsychotics are the first-line treatments for schizophrenia, but these classes of drugs are not universally effective, and they can have serious side effects that impact compliance. Antipsychotic drugs generally target the dopamine pathways with some variation. As research of schizophrenia pathophysiology has shifted away from a strictly dopamine-centric focus, the development of new pharmacotherapies has waned. A field of inquiry with centuries-old roots is gaining traction in psychiatric research circles and may represent a new frontier for drug discovery in schizophrenia. At the forefront of this investigative effort is the immune system and its many components, pathways and phenotypes, which are now known to actively engage the brain. Studies in schizophrenia reveal an intricate association of environmentally-driven immune activation in concert with a disrupted genetic template. A consistent conduit through this gene-environmental milieu is the gut-brain axis, which when dysregulated can generate pathological autoimmunity. In this review, we present epidemiological and biochemical evidence in support of an autoimmune component in schizophrenia and depict gut processes and a dysbiotic microbiome as a source and perpetuator of autoimmune dysfunction in the brain. Within this framework, we review the role of infectious agents, inflammation, gut dysbioses and autoantibody propagation on CNS pathologies such as neurotransmitter receptor hypofunction and complement pathway-mediated synaptic pruning. We then review the new pharmacotherapeutic horizon and novel agents directed to impact these pathological conditions. At the core of this discourse is the understanding that schizophrenia is etiologically and pathophysiologically heterogeneous and thus its treatment requires individualized attention with disease state variants diagnosed with objective biomarkers.
Collapse
Affiliation(s)
| | | | - Robert H Yolken
- Johns Hopkins University School of Medicine, Baltimore, MD, USA
| |
Collapse
|
26
|
Abstract
PURPOSE OF REVIEW Viruses, particularly herpes simplex virus (HSV), may be a cause of Alzheimer's disease (AD). The evidence supporting the viral hypothesis suggests that antiviral treatment trials, which have not been conducted, are warranted. RECENT FINDINGS HSV1 (oral herpes) and HSV2 (genital herpes) can trigger amyloid aggregation, and their DNA is common in amyloid plaques. HSV1 reactivation is associated with tau hyperphosphorylation and possibly tau propagation. Anti-HSV drugs reduce Aβ and p-tau accumulation in infected mouse brains. Clinically, after the initial oral infection, herpes simplex virus-1 (HSV1) becomes latent in the trigeminal ganglion and recurrent reactivation may produce neuronal damage and AD pathology. Clinical studies show cognitive impairment in HSV seropositive patients, and antiviral drugs show strong efficacy against HSV. An antiviral treatment trial in AD is clearly warranted. A phase II treatment trial with valacyclovir, an anti-HSV drug, recently began with evaluation of clinical and biomarker outcomes.
Collapse
|
27
|
Daxini A, Cronin K, Sreih AG. Vasculitis associated with immune checkpoint inhibitors-a systematic review. Clin Rheumatol 2018; 37:2579-84. [PMID: 29923081 DOI: 10.1007/s10067-018-4177-0] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/05/2018] [Accepted: 06/07/2018] [Indexed: 12/13/2022]
Abstract
Recent experimental and genetic studies have implicated the role of programmed cell death protein 1 (PD-1), programmed cell death protein-ligand 1 (PDL-1), and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) in the pathogenesis of medium and large vessel vasculitis. This study sought to evaluate the occurrence and nature of vasculitis associated with cancer treatment using immune checkpoint inhibition (anti-PD-1, anti-PDL-1, and anti-CTLA4). A systematic review of the medical literature was conducted by searching all available clinical data up to February 2018 in several databases and search engines including Cochrane Library, Embase, Google Scholar, Medline, Scopus, Web of Science, and Clinicaltrials.gov . Searches included the following FDA-approved anti-PD1 (nivolumab and pembrolizumab), anti-PDL1 (atezolizumab, avelumab, and durvalumab), and anti-CTLA4 (ipilimumab). The vasculitis cases were compiled and classified based on the 2012 revised Chapel Hill Consensus Conference nomenclature. The clinical feature of the vasculitis cases and their relationship to immune checkpoint inhibition was assessed. There were 53 cases of vasculitis of which 20 were confirmed. The main reported type of vasculitis was large vessel vasculitis and vasculitis of the central and peripheral nervous system. All cases resolved with either holding the immune checkpoint inhibitors and/or administering glucocorticoids. No death related to vasculitis was reported. Vasculitis, namely large vessel and vasculitis of the nervous system, is associated with immune checkpoint inhibition. Results of this study add to the growing evidence regarding the relationship between immune checkpoints and vasculitis and suggest that the pathway may be a therapeutic target.
Collapse
|
28
|
Chvátalová V, Šebánková B, Hrbáčková H, Tureček P, Flegr J. Differences in cognitive functions between cytomegalovirus-infected and cytomegalovirus-free university students: a case control study. Sci Rep 2018; 8:5322. [PMID: 29593335 DOI: 10.1038/s41598-018-23637-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 03/05/2018] [Indexed: 11/23/2022] Open
Abstract
Cytomegalovirus (CMV) is the herpetic virus, which infects 45–100% people worldwide. Many reports suggest that CMV could impair cognitive functions of infected subjects. Here we searched for indices of effects of CMV on infected subjects’ intelligence and knowledge. The Intelligence Structure Test I-S-T 2000 R was used to compare IQ of 148 CMV-infected and 135 CMV-free university students. Infected students expressed higher intelligence. Paradoxically, their IQ decreased with decreasing concentration of anti-CMV antibodies, which can be used, statistically, as a proxy of the time passed from the moment of infection in young subjects when the age of subjects is statistically controlled. The paradox of seemingly higher intelligence of CMV infected subjects could be explained by the presence of the subpopulation of about 5–10% CMV-positive individuals in the population of “CMV-negative students”. These false negative subjects had probably not only the oldest infections and therefore the lowest concentration of anamnestic antibodies, but also the lowest intelligence among the infected students. Prevalence of CMV infection in all countries is very high, approaching sometimes 90%. Therefore, the total impact of CMV on human intelligence may be large.
Collapse
|
29
|
Bhatia T, Wood J, Iyengar S, Narayanan SS, Beniwal RP, Prasad KM, Chen K, Yolken RH, Dickerson F, Gur RC, Gur RE, Deshpande SN, Nimgaonkar VL. Emotion discrimination in humans: Its association with HSV-1 infection and its improvement with antiviral treatment. Schizophr Res 2018; 193:161-7. [PMID: 28830742 DOI: 10.1016/j.schres.2017.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/03/2017] [Accepted: 08/03/2017] [Indexed: 12/23/2022]
Abstract
BACKGROUND Herpes simplex virus, type 1 (HSV-1) infects over 3.4 billion people, world-wide. Though it can cause encephalitis, in the vast majority it is asymptomatic, with lifelong latent infection in neurons. HSV-1 infected individuals have greater cognitive dysfunction than uninfected individuals, particularly persons with schizophrenia - even without encephalitis. We investigated whether HSV-1 related cognitive dysfunction is progressive or remediable. METHODS In a prospective naturalistic follow up sample (PNFU), temporal changes in cognitive functions were analyzed in relation to baseline HSV-1 infection in persons with/without schizophrenia (N=226). Independently, in a randomized controlled trial (RCT), HSV-1 infected, clinically stabilized SZ outpatients received Valacyclovir (VAL, an HSV-1 specific antiviral, 1.5G twice daily for 16weeks) or placebo (PLA) added to standard antipsychotic treatment, using a stratified randomization design, following placebo run-in (N=67). In both samples, HSV-1 infection (seropositivity) was estimated using serum IgG antibodies. Clinical evaluations were blinded to HSV-1 or treatment status. Standardized Z scores for accuracy on eight cognitive domains were analyzed for temporal trajectories using generalized linear models (PNFU) and VAL/PLA differences compared with intent to treat analyses (RCT). RESULTS PNFU: At baseline, HSV-1 infected participants had significantly lower accuracy scores for Emotion Identification and Discrimination (EMOD), Spatial memory and Spatial ability, regardless of SZ diagnosis (p=0.025, 0.029, 0.046, respectively). They also had significantly steeper temporal worsening for EMOD (p=0.03). RCT: EMOD improved in VAL-treated patients (p=0.048, Cohen's d=0.43). CONCLUSIONS A proportion of age related decline in EMOD is attributable to HSV-1 infection.
Collapse
|
30
|
Hogestyn JM, Mock DJ, Mayer-Proschel M. Contributions of neurotropic human herpesviruses herpes simplex virus 1 and human herpesvirus 6 to neurodegenerative disease pathology. Neural Regen Res 2018; 13:211-221. [PMID: 29557362 PMCID: PMC5879884 DOI: 10.4103/1673-5374.226380] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Human herpesviruses (HVs) have developed ingenious mechanisms that enable them to traverse the defenses of the central nervous system (CNS). The ability of HVs to enter a state of latency, a defining characteristic of this viral family, allows them to persist in the human host indefinitely. As such, HVs represent the most frequently detected pathogens in the brain. Under constant immune pressure, these infections are largely asymptomatic in healthy hosts. However, many neurotropic HVs have been directly connected with CNS pathology in the context of other stressors and genetic risk factors. In this review, we discuss the potential mechanisms by which neurotropic HVs contribute to neurodegenerative disease (NDD) pathology by highlighting two prominent members of the HV family, herpes simplex virus 1 (HSV-1) and human herpesvirus 6 (HHV-6). We (i) introduce the infectious pathways and replicative cycles of HSV-1 and HHV-6 and then (ii) review the clinical evidence supporting associations between these viruses and the NDDs Alzheimer's disease (AD) and multiple sclerosis (MS), respectively. We then (iii) highlight and discuss potential mechanisms by which these viruses exert negative effects on neurons and glia. Finally, we (iv) discuss how these viruses could interact with other disease-modifying factors to contribute to the initiation and/or progression of NDDs.
Collapse
Affiliation(s)
| | - David J Mock
- Department of Biomedical Genetics, University of Rochester, Rochester, NY, USA
| | - Margot Mayer-Proschel
- Department of Neuroscience, University of Rochester; Department of Biomedical Genetics, University of Rochester, Rochester, NY, USA
| |
Collapse
|
31
|
Nimgaonkar VL, Yolken RH, Wang T, Chang CC, McClain L, McDade E, Snitz BE, Ganguli M. Temporal Cognitive Decline Associated With Exposure to Infectious Agents in a Population-based, Aging Cohort. Alzheimer Dis Assoc Disord 2016; 30:216-22. [PMID: 26710257 DOI: 10.1097/WAD.0000000000000133] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Numerous cross-sectional studies have related exposure to neurotropic infectious agents with cognitive dysfunction in older adults, however, the temporal sequence is uncertain. METHODS In a representative, well-characterized, population-based aging cohort, we determined whether the temporal trajectories of multiple cognitive domains are associated with exposure to cytomegalovirus (CMV), Herpes Simplex virus, type 1 (HSV-1), Herpes Simplex virus, type 2 (HSV-2), or Toxoplasma gondii (TOX). Complex attention, executive functions, memory, language, and visuospatial function were assessed annually for 5 years among consenting individuals. Study entry IgG antibody titers indexing exposure to each infectious agent were examined in relation to slopes of subsequent temporal cognitive decline using multiple linear regressions adjusted for potential confounders. RESULTS The IgG levels for HSV-2 were significantly associated with baseline cognitive domain scores (N=1022 participants). Further, the IgG levels for HSV-2, TOX, and CMV, but not HSV-1 were significantly associated with greater temporal cognitive decline that varied by type of infection. CONCLUSIONS Exposure to CMV, HSV-2, or TOX is associated with cognitive deterioration in older individuals, independent of general age-related variables. An increased understanding of the role of infectious agents in cognitive decline may lead to new methods for its prevention and treatment.
Collapse
|
32
|
Olsson J, Kok E, Adolfsson R, Lövheim H, Elgh F. Herpes virus seroepidemiology in the adult Swedish population. Immun Ageing 2017; 14:10. [PMID: 28491117 PMCID: PMC5424393 DOI: 10.1186/s12979-017-0093-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 05/05/2017] [Indexed: 01/01/2023]
Abstract
Background Herpes viruses establish a life-long latency and can cause symptoms during both first-time infection and later reactivation. The aim of the present study was to describe the seroepidemiology of Herpes simplex type 1 (HSV1), Herpes simplex type 2 (HSV2), Cytomegalovirus (CMV), Varicella Zoster virus (VZV) and Human herpes virus type 6 (HHV6) in an adult Swedish population (35–95 years of age). Methods Presence of antibodies against the respective viruses in serum from individuals in the Betula study was determined with an enzyme-linked immunosorbent assay (ELISA). Singular samples from 535 persons (53.9% women, mean age at inclusion 62.7 ± 14.4 years) collected 2003-2005 were analyzed for the five HHVs mentioned above. In addition, samples including follow-up samples collected 1988–2010 from 3,444 persons were analyzed for HSV. Results Prevalence of HSV1 was 79.4%, HSV2 12.9%, CMV 83.2%, VZV 97.9%, and HHV6 97.5%. Herpes virus infections were more common among women (p = 0.010) and a lower age-adjusted HSV seroprevalence was found in later birth cohorts (p < 0.001). The yearly incidence of HSV infection was estimated at 14.0/1000. Conclusion Women are more often seropositive for HHV, especially HSV2. Age-adjusted seroprevalence for HSV was lower in later birth cohorts indicating a decreasing childhood and adolescent risk of infection.
Collapse
Affiliation(s)
- Jan Olsson
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
| | - Eloise Kok
- Department of Forensic Medicine, University of Tampere, Tampere, 33520 Finland
| | - Rolf Adolfsson
- Department of Clinical Sciences, Psychiatry, Umeå University, Umeå, Sweden
| | - Hugo Lövheim
- Department of Community Medicine and Rehabilitation, Geriatric Medicine, Umeå University, Umeå, Sweden
| | - Fredrik Elgh
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
| |
Collapse
|
33
|
Wyman CP, Gale SD, Hedges-Muncy A, Erickson LD, Wilson E, Hedges DW. Association between Toxoplasma gondii seropositivity and memory function in nondemented older adults. Neurobiol Aging 2017; 53:76-82. [PMID: 28235681 PMCID: PMC5482532 DOI: 10.1016/j.neurobiolaging.2017.01.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 01/19/2017] [Accepted: 01/24/2017] [Indexed: 02/06/2023]
Abstract
Toxoplasma gondii (T. gondii) seropositivity may be associated with decreased memory in older adults. To further investigate the association between T. gondii seropositivity and memory in nondemented older adults, we obtained serum samples from 114 nondemented older adults evaluated by the Alzheimer's Disease and Research Center at Washington University in St. Louis, Missouri, USA. We determined T. gondii seropositivity and anti-T. gondii IgG antibody titer and examined associations with memory function while controlling for socioeconomic status, education level, age, and apolipoprotein E4 status. There were few associations between T. gondii seropositivity or anti-T. gondii IgG antibodies and memory, although there was some support suggesting an interaction between anti-T. gondii and sex. In the seropositive-only sample, there was an inverse relationship between anti-T. gondii titer and performance on the selective reminding test. Overall, we found little evidence of an association between impaired memory function and T. gondii seropositivity and anti-T. gondii IgG antibodies in this sample of nondemented older adults.
Collapse
Affiliation(s)
- Cynthia P Wyman
- Department of Psychology, Brigham Young University, Provo, UT, USA
| | - Shawn D Gale
- Department of Psychology, Brigham Young University, Provo, UT, USA; The Neuroscience Center, Brigham Young University, Provo, UT, USA.
| | | | - Lance D Erickson
- Department of Sociology, Brigham Young University, Provo, UT, USA
| | - Eric Wilson
- Department of Microbiology & Molecular Biology, Brigham Young University, Provo, UT, USA
| | - Dawson W Hedges
- Department of Psychology, Brigham Young University, Provo, UT, USA; The Neuroscience Center, Brigham Young University, Provo, UT, USA
| |
Collapse
|
34
|
Vanyukov MM, Nimgaonkar VL, Kirisci L, Kirillova GP, Reynolds MD, Prasad K, Tarter RE, Yolken RH. Association of cognitive function and liability to addiction with childhood herpesvirus infections: A prospective cohort study. Dev Psychopathol 2018; 30:143-52. [PMID: 28420448 DOI: 10.1017/S0954579417000529] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Liability to substance use disorder (SUD) is largely nonspecific to particular drugs and is related to behavior dysregulation, including reduced cognitive control. Recent data suggest that cognitive mechanisms may be influenced by exposure to neurotropic infections, such as human herpesviruses. In this study, serological evidence of exposure to human herpesvirus Herpes simplex virus Type 1 (HSV-1), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) as well as Toxoplasma gondii was determined in childhood (age ~11 years) in 395 sons and 174 daughters of fathers with or without SUD. Its relationships with a cognitive characteristic (IQ) in childhood and with risk for SUD in adulthood were examined using correlation, regression, survival, and path analyses. Exposure to HSV-1, EBV, and T. gondii in males and females, and CMV in males, was associated with lower IQ. Independent of that relationship, EBV in females and possibly in males, and CMV and possibly HSV-1 in females were associated with elevated risk for SUD. Therefore, childhood neurotropic infections may influence cognitive development and risk for behavior disorders such as SUD. The results may point to new avenues for alleviating cognitive impairment and SUD risk.
Collapse
|
35
|
Gale SD, Erickson LD, Berrett A, Brown BL, Hedges DW. Infectious disease burden and cognitive function in young to middle-aged adults. Brain Behav Immun 2016; 52:161-8. [PMID: 26598104 DOI: 10.1016/j.bbi.2015.10.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 10/23/2015] [Accepted: 10/23/2015] [Indexed: 11/20/2022] Open
Abstract
Prior research has suggested an association between exposure to infectious disease and neurocognitive function in humans. While most of these studies have explored individual viral, bacterial, and even parasitic sources of infection, few have considered the potential neurocognitive burden associated with multiple infections. In this study, we utilized publically available data from a large dataset produced by the Centers for Disease Control and Prevention that included measures of neurocognitive function, sociodemographic variables, and serum antibody data for several infectious diseases. Specifically, immunoglobulin G antibodies for toxocariasis, toxoplasmosis, hepatitis A, hepatitis B, and hepatitis C, cytomegalovirus, and herpes 1 and 2 were available in 5662 subjects. We calculated an overall index of infectious-disease burden to determine if an aggregate measure of exposure to infectious disease would be associated with neurocognitive function in adults aged 20-59 years. The index predicted processing speed and learning and memory but not reaction time after controlling for age, sex, race-ethnicity, immigration status, education, and the poverty-to-income ratio. Interactions between the infectious-disease index and some sociodemographic variables were also associated with neurocognitive function. In summary, an index aggregating exposure to several infectious diseases was associated with neurocognitive function in young- to middle-aged adults.
Collapse
|
36
|
de Witte LD, van Mierlo HC, Litjens M, Klein HC, Bahn S, Osterhaus AD. The association between antibodies to neurotropic pathogens and schizophrenia: a case-control study. NPJ Schizophr 2015; 1:15041. [PMID: 27336045 PMCID: PMC4849462 DOI: 10.1038/npjschz.2015.41] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/08/2015] [Accepted: 09/14/2015] [Indexed: 12/05/2022]
Abstract
Background: Exposure to neurotropic pathogens has been proposed as an environmental risk factor for schizophrenia and can be evaluated by measuring pathogen-specific immunoglobulin G (IgG). Seroprevalence of pathogen-specific IgG reflects prior exposure, whereas IgG levels are associated with reactivity or reinfection. Several studies have examined these parameters in schizophrenia. However, results still remain inconclusive, as several previous studies did not correct for important confounding factors. Aims: To investigate whether schizophrenia is associated with prior exposure to neurotropic pathogens, or with their reactivation. Methods: We examined the seroprevalence and titer of IgG antibodies against herpes simplex virus-1 and -2 (HSV-1/HSV-2), varicella zoster virus (VZV), Epstein–Barr virus (EBV), cytomegalovirus (CMV), and Toxoplasma gondii (TG) in plasma of 368 adult patients with a schizophrenia spectrum disorder and 282 controls using ELISA. Results: We did not find evidence for an increased exposure to HSV-1, HSV-2, EBV, and TG in patients. There was a significantly higher seroprevalence of VZV (98.9% vs. 95.6%, P<0.05) and CMV (40.4% vs. 27.7%, P<0.001) in controls as compared with patients, which did not remain statistically significant after adjustment for various potential confounders. We did not find significant differences in antibody titers of seropositive patients and controls for any of the six pathogens. Conclusions: Our results do not support the hypothesis that increased exposure to neurotropic pathogens after birth is associated with schizophrenia.
Collapse
Affiliation(s)
- Lot D de Witte
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht , Utrecht, The Netherlands
| | - Hans C van Mierlo
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht , Utrecht, The Netherlands
| | - Manja Litjens
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht , Utrecht, The Netherlands
| | - Hans C Klein
- Department of Psychiatry, University of Groningen , Groningen, The Netherlands
| | - Sabine Bahn
- Department of Chemical Engineering and Biotechnology, University of Cambridge , Cambridge, UK
| | - Ab D Osterhaus
- Department of Viroscience, Erasmus University Medical Center , Rotterdam, The Netherlands
| | | |
Collapse
|
37
|
Fruchter E, Goldberg S, Fenchel D, Grotto I, Ginat K, Weiser M. The impact of Herpes simplex virus type 1 on cognitive impairments in young, healthy individuals - A historical prospective study. Schizophr Res 2015; 168:292-6. [PMID: 26362735 DOI: 10.1016/j.schres.2015.08.036] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 08/23/2015] [Accepted: 08/24/2015] [Indexed: 11/29/2022]
Abstract
Herpes simplex virus (HSV) is a highly prevalent neurotropic virus. Although on the whole, chronic, latent or persistent infection is considered to be relatively benign, HSV infections can cause cognitive impairment during and after acute encephalitis. Some studies have documented cognitive impairment in exposed persons that is untraceable to encephalitis. Most studies have focused on these impairments in the mentally ill, mostly among individuals with schizophrenia, and only recently have studies begun to examine the impact of HSV infection on the cognition of healthy individuals. Subjects were a representative, random sample of 612 soldiers before active duty in the Israeli military (Israeli defense force - IDF), 62.2% HSV positive (n=381) and 38.8% HSV negative (n=231). Cognitive functioning and language abilities were compared between these groups, controlling for years of education, immigration status, and gender. Compared to soldiers who were sero-negative, soldiers who were sero-positive for HSV had significantly lower IQ scores (IQ=97.96, SD=15.19 vs IQ=103.23, SD=14.23; p≤0.001, effect size (ES)=0.2), and significantly lower Hebrew language scores (ES=0.1, p≤0.01). The results remained significant after removing subjects with mild depression, anxiety or personality disorders. Although we could not control for socio-economic status directly, our findings indicate that infection with HSV-1 is associated with reduced cognitive functioning in healthy individuals. This finding adds to the growing number of studies in the schizophrenia literature and indicates that many research findings seemingly characteristic of schizophrenia are related to the association between HSV exposure and cognitive functioning in general, and are not illness specific.
Collapse
Affiliation(s)
- Eyal Fruchter
- IDF Medical Corps, Mental Health Center, Israel; USC - School of Social Work, C.I.R. Los Angeles, CA, USA
| | - Shira Goldberg
- Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
| | - Daphna Fenchel
- Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
| | - Itamar Grotto
- Ministry of Health, Jerusalem, Israel; Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Keren Ginat
- IDF Medical Corps, Mental Health Center, Israel
| | - Mark Weiser
- IDF Medical Corps, Mental Health Center, Israel; Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel; Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel.
| |
Collapse
|
38
|
D’Aiuto L, Prasad KM, Upton CH, Viggiano L, Milosevic J, Raimondi G, McClain L, Chowdari K, Tischfield J, Sheldon M, Moore JC, Yolken RH, Kinchington PR, Nimgaonkar VL. Persistent infection by HSV-1 is associated with changes in functional architecture of iPSC-derived neurons and brain activation patterns underlying working memory performance. Schizophr Bull 2015; 41:123-32. [PMID: 24622295 PMCID: PMC4266288 DOI: 10.1093/schbul/sbu032] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Herpes simplex virus, type 1 (HSV-1) commonly produces lytic mucosal lesions. It invariably initiates latent infection in sensory ganglia enabling persistent, lifelong infection. Acute HSV-1 encephalitis is rare and definitive evidence of latent infection in the brain is lacking. However, exposure untraceable to encephalitis has been repeatedly associated with impaired working memory and executive functions, particularly among schizophrenia patients. METHODS Patterns of HSV-1 infection and gene expression changes were examined in human induced pluripotent stem cell (iPSC)-derived neurons. Separately, differences in blood oxygenation level-dependent (BOLD) responses to working memory challenges using letter n-back tests were investigated using functional magnetic resonance imaging (fMRI) among schizophrenia cases/controls. RESULTS HSV-1 induced lytic changes in iPSC-derived glutamatergic neurons and neuroprogenitor cells. In neurons, HSV-1 also entered a quiescent state following coincubation with antiviral drugs, with distinctive changes in gene expression related to functions such as glutamatergic signaling. In the fMRI studies, main effects of schizophrenia (P = .001) and HSV-1 exposure (1-back, P = 1.76 × 10(-4); 2-back, P = 1.39 × 10(-5)) on BOLD responses were observed. We also noted increased BOLD responses in the frontoparietal, thalamus, and midbrain regions among HSV-1 exposed schizophrenia cases and controls, compared with unexposed persons. CONCLUSIONS The lytic/quiescent cycles in iPSC-derived neurons indicate that persistent neuronal infection can occur, altering cellular function. The fMRI studies affirm the associations between nonencephalitic HSV-1 infection and functional brain changes linked with working memory impairment. The fMRI and iPSC studies together provide putative mechanisms for the cognitive impairments linked to HSV-1 exposure.
Collapse
Affiliation(s)
- Leonardo D’Aiuto
- Department of Psychiatry, WPIC, University of Pittsburgh, School of Medicine, Pittsburgh PA;,These authors contributed equally to the article
| | - Konasale M. Prasad
- Department of Psychiatry, WPIC, University of Pittsburgh, School of Medicine, Pittsburgh PA;,These authors contributed equally to the article
| | - Catherine H. Upton
- Department of Psychiatry, WPIC, University of Pittsburgh, School of Medicine, Pittsburgh PA
| | - Luigi Viggiano
- Department of Biology, University of Bari “Aldo Moro”, Bari, Italy
| | - Jadranka Milosevic
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Giorgio Raimondi
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Lora McClain
- Department of Psychiatry, WPIC, University of Pittsburgh, School of Medicine, Pittsburgh PA
| | - Kodavali Chowdari
- Department of Psychiatry, WPIC, University of Pittsburgh, School of Medicine, Pittsburgh PA
| | - Jay Tischfield
- Department of Genetics and The Human Genome Institute of New Jersey, Rutgers, The State University of New Jersey, Piscataway, NJ
| | - Michael Sheldon
- Department of Genetics and The Human Genome Institute of New Jersey, Rutgers, The State University of New Jersey, Piscataway, NJ
| | - Jennifer C. Moore
- Department of Genetics and The Human Genome Institute of New Jersey, Rutgers, The State University of New Jersey, Piscataway, NJ
| | - Robert H. Yolken
- Stanley Division of Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Paul R. Kinchington
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA;,Department of Molecular Genetics & Biochemistry, University of Pittsburgh, Pittsburgh, PA
| | - Vishwajit L. Nimgaonkar
- Department of Psychiatry, WPIC, University of Pittsburgh, School of Medicine, Pittsburgh PA;,Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA,*To whom correspondence should be addressed; Western Psychiatric Institute and Clinic, TDH 441, 3811 O’Hara St, Pittsburgh, PA 15213, US; tel: 412-246-6353, fax: 412-246-6350, e-mail:
| |
Collapse
|
39
|
Gutiérrez-Fernández J, Luna Del Castillo JDD, Mañanes-González S, Carrillo-Ávila JA, Gutiérrez B, Cervilla JA, Sorlózano-Puerto A. Different presence of Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, and Toxoplasma gondii in schizophrenia: meta-analysis and analytical study. Neuropsychiatr Dis Treat 2015; 11:843-52. [PMID: 25848282 PMCID: PMC4384747 DOI: 10.2147/ndt.s79285] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In the present study we have performed both a meta-analysis and an analytical study exploring the presence of Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, and Toxoplasma gondii antibodies in a sample of 143 schizophrenic patients and 143 control subjects. The meta-analysis was performed on papers published up to April 2014. The presence of serum immunoglobulin G and immunoglobulin A was performed by enzyme-linked immunosorbent assay test. The detection of microbial DNA in total peripheral blood was performed by nested polymerase chain reaction. The meta-analysis showed that: 1) C. pneumoniae DNA in blood and brain are more common in schizophrenic patients; 2) there is association with parasitism by T. gondii, despite the existence of publication bias; and 3) herpes viruses were not more common in schizophrenic patients. In our sample only anti-Toxoplasma immunoglobulin G was more prevalent and may be a risk factor related to schizophrenia, with potential value for prevention.
Collapse
Affiliation(s)
| | | | | | | | - Blanca Gutiérrez
- Department of Psychiatry, Institute of Neurosciences and CIBERSAM, School of Medicine and Biohealth Research Institute (Instituto de Investigación Biosanitaria) IBS-Granada, University of Granada, Granada, Spain
| | - Jorge A Cervilla
- Department of Psychiatry, Institute of Neurosciences and CIBERSAM, School of Medicine and Biohealth Research Institute (Instituto de Investigación Biosanitaria) IBS-Granada, University of Granada, Granada, Spain
| | | |
Collapse
|
40
|
Khandaker GM, Stochl J, Zammit S, Lewis G, Jones PB. Childhood Epstein-Barr Virus infection and subsequent risk of psychotic experiences in adolescence: a population-based prospective serological study. Schizophr Res 2014; 158:19-24. [PMID: 25048425 PMCID: PMC4561501 DOI: 10.1016/j.schres.2014.05.019] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/25/2014] [Accepted: 05/15/2014] [Indexed: 01/27/2023]
Abstract
BACKGROUND Several studies suggest a link between early-life infection and adult schizophrenia. Cross-sectional studies have reported: (1) increased prevalence of Epstein-Barr Virus (EBV), a member of the Herpesviridae family in schizophrenia; (2) a possible role of Herpes simplex virus in cognitive dysfunction in schizophrenia and healthy controls. We report a longitudinal serological study of early-life EBV infection, childhood IQ, and subsequent risk of psychotic experiences (PE) in adolescence. METHODS Serum antibodies to EBV (anti-VCA IgG) were measured in 530 participants from the ALSPAC cohort at age 4 years. Assessments for IQ at age 9 and PE at age 13 were attended by 401 and 366 of these individuals, respectively. Logistic regression calculated odds ratio (OR) for PE in EBV-exposed, compared with unexposed group. Mean IQ scores were compared between these groups; effect of IQ on the EBV-PE association was examined. Potential confounders included age, gender, ethnicity, social class, household crowding, and concurrent depression and anxiety. RESULTS About 25% of the sample was exposed to EBV at age 4. EBV exposure was associated with subsequent risk of definite PE in adolescence; OR 5.37 (95% CI 1.71-16.87), which remained significant after confounding adjustment. EBV-exposed individuals compared with unexposed performed worse on all IQ measures; mean difference in full-scale IQ 4.15 (95% CI 0.44-7.87); however, this was explained by socio-demographic differences. The EBV-PE association was not explained by IQ. CONCLUSIONS Early-life exposure to EBV is associated with PE in adolescence, consistent with a role of infection/immune dysfunction in the aetiology of psychosis.
Collapse
Affiliation(s)
- Golam M Khandaker
- Department of Psychiatry, University of Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK; Centre for Mental Health, Addiction and Suicide Research, School of Social and Community Medicine, University of Bristol, UK.
| | - Jan Stochl
- Department of Psychiatry, University of Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Stanley Zammit
- Centre for Mental Health, Addiction and Suicide Research, School of Social and Community Medicine, University of Bristol, UK; Institute of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, UK
| | - Glyn Lewis
- Centre for Mental Health, Addiction and Suicide Research, School of Social and Community Medicine, University of Bristol, UK; Division of Psychiatry, University College London, UK
| | - Peter B Jones
- Department of Psychiatry, University of Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| |
Collapse
|
41
|
Jonker I, Klein HC, Duivis HE, Yolken RH, Rosmalen JGM, Schoevers RA. Association between exposure to HSV1 and cognitive functioning in a general population of adolescents. The TRAILS study. PLoS One 2014; 9:e101549. [PMID: 24983885 PMCID: PMC4077793 DOI: 10.1371/journal.pone.0101549] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 06/08/2014] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Infections with different herpes viruses have been associated with cognitive functioning in psychiatric patients and healthy adults. The aim of this study was to find out whether antibodies to different herpes viruses are prospectively associated with cognitive functioning in a general adolescent population. METHODS This study was performed in TRAILS, a large prospective general population cohort (N = 1084, 54% female, mean age 16.2 years (SD 0.6)). At age 16, immunoglobulin G antibodies against HSV1, HSV2, CMV and EBV were measured next to high sensitive C-Reactive Protein (hsCRP). Two years later, immediate memory and executive functioning were assessed using the 15 words task and the self ordered pointing task. Multiple linear regression analysis with bootstrapping was performed to study the association between viral infections and cognitive function, adjusting for gender, socioeconomic status, ethnicity, and cannabis use. RESULTS Presence of HSV1 antibodies was associated with memory function ((B = -0.272, 95% CI = -0.556 to -0.016, p = 0.047)), while the association with executive functioning did not reach statistical significance (B = 0.560, 95% CI is -0.053 to 1.184, p = 0.075). The level of HSV1 antibodies was associated with both memory function (B = -0.160, 95% CI = -0.280 to -0.039, p = 0.014) and executive functioning (B = 0.296, 95% CI = 0.011 to 0.578, p = 0.046). Other herpes viruses and hsCRP were not associated with cognitive functioning. CONCLUSIONS Both presence and level of HSV1 antibodies are prospectively associated with reduced cognitive performance in a large cohort of adolescents.
Collapse
Affiliation(s)
- Iris Jonker
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Interdisciplinary Center for Psychopathology and Emotion regulation (ICPE), Groningen, The Netherlands
- * E-mail:
| | - Hans C. Klein
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Interdisciplinary Center for Psychopathology and Emotion regulation (ICPE), Groningen, The Netherlands
| | - Hester E. Duivis
- Center of Research on Psychology in Somatic Diseases, Department of Medical and Neuropsychology, Tilburg University, Tilburg, The Netherlands
| | - Robert H. Yolken
- Johns Hopkins Medical School, Baltimore, Maryland, United States of America
| | - Judith G. M. Rosmalen
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Interdisciplinary Center for Psychopathology and Emotion regulation (ICPE), Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Department of Internal Medicine, Groningen, The Netherlands
| | - Robert A. Schoevers
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Interdisciplinary Center for Psychopathology and Emotion regulation (ICPE), Groningen, The Netherlands
| |
Collapse
|
42
|
Tarter KD, Simanek AM, Dowd JB, Aiello AE. Persistent viral pathogens and cognitive impairment across the life course in the third national health and nutrition examination survey. J Infect Dis 2014; 209:837-44. [PMID: 24253286 PMCID: PMC3935478 DOI: 10.1093/infdis/jit616] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 10/02/2013] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Herpesviruses have been linked to cognitive impairment in older individuals but little is known about the association in the general US population. METHODS We determined whether cytomegalovirus (CMV) and herpes simplex virus 1 (HSV-1) seropositivity were associated with cognitive impairment among children (aged 6-16 years) and adults aged 20-59 or ≥60 years, using data from the National Health and Nutrition Examination Survey (NHANES) III. Linear and logistic regression models were used to examine the associations between pathogen seropositivity and cognitive impairment. RESULTS Among children, HSV-1 seropositivity was associated with lower reading and spatial reasoning test scores (β, -0.69; 95% confidence interval [CI], -1.18 to -.21 and β, -0.82; 95% CI, -1.29 to -.36, respectively). Among middle-aged adults, HSV-1 and CMV seropositivity were associated with impaired coding speed (odds ratio [OR], 1.54; 95% CI, 1.13-2.11, and OR, 1.41; 95% CI, 1.09-1.82, respectively). CMV seropositivity was also associated with impaired learning and recall (OR, 1.43; 95% CI, 1.14-1.80). Among older adults, HSV-1 seropositivity was associated with immediate memory impairment (OR, 3.26; 95% CI, 1.68-6.32). CONCLUSIONS Future studies examining the biological pathways by which herpesviruses influence cognitive impairment across the life course are warranted.
Collapse
Affiliation(s)
- Kara D. Tarter
- Department of Epidemiology, Center for Social Epidemiology & Population Health, University of Michigan School of Public Health, Ann Arbor, MI
| | - Amanda M. Simanek
- University of Wisconsin-Milwaukee, Joseph J. Zilber School of Public Health, Milwaukee, WI
| | - Jennifer B. Dowd
- CUNY School of Public Health, Hunter College, City University of New York, NY
| | - Allison E. Aiello
- Department of Epidemiology, Center for Social Epidemiology & Population Health, University of Michigan School of Public Health, Ann Arbor, MI
| |
Collapse
|
43
|
Luz Correa B, Ornaghi AP, Cerutti Muller G, Engroff P, Pestana Lopes R, Gomes da Silva Filho I, Bosch JA, Bonorino C, Bauer ME. The inverted CD4:CD8 ratio is associated with cytomegalovirus, poor cognitive and functional states in older adults. Neuroimmunomodulation 2014; 21:206-12. [PMID: 24504177 DOI: 10.1159/000356827] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 10/25/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Some premature features of immunosenescence have been associated with persistent viral infections and altered populations of T cells. In particular, the inverted T CD4:CD8 ratio has been correlated with increased morbidity and mortality across different age groups. OBJECTIVE Here, we investigated the role of persistent viral infections, cognitive and functional states as predictors of inverted CD4:CD8 ratio of older adults in a developing country. METHODS Three hundred and sixty community-dwelling older adults (aged 60-103 years) were recruited. Cognitive function was evaluated by the Instrument of Brief Neuropsychological Assessment and Mini-Mental State Examination inventory. Functional Activities Questionnaire was used to determine activities of daily living. Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) serologies were determined by ELISAs. Peripheral blood was assessed for lymphocyte subsets by flow cytometry (CD4+, CD8+, NK, NKT, B and CD8+CD28-). RESULTS Fifty-nine individuals were identified with CD4:CD8 ratio <1, and had increased IgG titers to CMV (p < 0.01), but not to EBV, compared to subjects with CD4:CD8 ratio >1. The older adults with inverted CD4:CD8 ratio had impairments in some cognitive dimensions and had more functional disability and dependency (p = 0.01) than subjects with CD4:CD8 ratio >1. The lymphocyte subsets did not vary between groups. The increased CMV-IgG titers alone contributed to 8× higher chance to invert CD4:CD8 T cell ratio (OR 8.12, 95% CI 1.74-37.88, p < 0.01). CONCLUSION Our data further indicate the role of CMV on circulating T cells, poor cognition and functional disability/dependency during aging.
Collapse
Affiliation(s)
- Bruna Luz Correa
- Laboratory of Immunosenescence, Institute of Biomedical Research, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Thomas P, Bhatia T, Gauba D, Wood J, Long C, Prasad K, Dickerson FB, Gur RE, Gur RC, Yolken RH, Nimgaonkar VL, Deshpande SN. Exposure to herpes simplex virus, type 1 and reduced cognitive function. J Psychiatr Res 2013; 47:1680-5. [PMID: 23920011 PMCID: PMC3809147 DOI: 10.1016/j.jpsychires.2013.07.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 07/03/2013] [Accepted: 07/03/2013] [Indexed: 12/25/2022]
Abstract
Herpes simplex virus, type 1 (HSV-1) causes cold sores, keratitis and rarely, fatal encephalitis. The infection is lifelong, with sensory ganglia serving as reservoirs of latent infection. Recently, exposure to HSV-1 has also been repeatedly associated with reduced cognitive function among healthy individuals without prior encephalitis. Though HSV-1 does not elevate risk for schizophrenia (SZ) per se, exposure is likewise associated with impaired cognitive functions among SZ patients. The range of cognitive changes observed in HSV-1 exposed persons has not been investigated systematically, nor is it known whether interaction between HSV-1 exposure and SZ related factors contributes to the impairment among SZ patients. Persons with or without schizophrenia/schizophreniform disorder (N = 298 total, DSM IV criteria) were assessed for HSV-1 exposure using serum HSV-1 antibody titers. The Penn Computerized Neurocognitive battery was used to assess eight cognitive domains with respect to accuracy and speed. There were no significant case-control differences in HSV-1 exposure. The SZ/schizophreniform disorder cases were significantly impaired in all cognitive domains compared with the controls. HSV-1 exposure was also associated with reduced cognitive function in the entire sample, but the magnitude of the effects and their patterns differed from the SZ related changes. Further, statistically significant interactions between HSV-1 exposure and SZ case status were not detected. HSV-1 exposure does not elevate risk for SZ, but it is associated with reduced function in specific cognitive domains regardless of SZ diagnostic status. An 'epidiagnostic' model for the association is proposed to explain the results.
Collapse
Affiliation(s)
- Pramod Thomas
- Department of Bio-Statistics, Dr S.M.C.S.I. Medical College, Karakonam, Thiruvananthapuram, Kerala, India
| | - Triptish Bhatia
- GRIP-NIH Project USA, Department of Psychiatry, Dr. RML Hospital, New Delhi India
| | | | - Joel Wood
- Department of Psychiatry, University of Pittsburgh School of Medicine, Western Psychiatric Institute and Clinic, Pittsburgh, Pennsylvania 15213, USA
| | - Colleen Long
- Department of Psychiatry, University of Pittsburgh School of Medicine, Western Psychiatric Institute and Clinic, Pittsburgh, Pennsylvania 15213, USA
| | - Konasale Prasad
- Department of Psychiatry, University of Pittsburgh School of Medicine, Western Psychiatric Institute and Clinic, Pittsburgh, Pennsylvania 15213, USA
| | - Faith B Dickerson
- Stanley Research Center, Sheppard Pratt Health System, 6501 North Charles St., Baltimore, MD 21204, USA
| | - Raquel E Gur
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104-4283, USA
| | - Ruben C Gur
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104-4283, USA
| | - Robert H Yolken
- Stanley Laboratory of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Vishwajit L Nimgaonkar
- Department of Psychiatry, University of Pittsburgh School of Medicine, Western Psychiatric Institute and Clinic, Pittsburgh, Pennsylvania 15213, USA,Department of Human Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Smita N Deshpande
- Department of Psychiatry, PGIMER-Dr. Ram Manohar Lohia Hospital, New Delhi, India
| |
Collapse
|
45
|
Abstract
The links between infectious agents and risk for schizophrenia have been widely debated, but few investigations have focused on "epidiagnostic" effects, eg, whether exposures to infectious agents alter key clinical aspects of the disorder, such as cognitive impairment. The present theme issue evaluates epidiagnostic cognitive effects of two common infectious agents, namely Herpes Simplex Virus, type 1 and Toxoplasma gondii.
Collapse
Affiliation(s)
- Vishwajit L. Nimgaonkar
- Departments of Psychiatry and Human Genetics, University of Pittsburgh School of Medicine and Graduate School of Public Health, Western Psychiatric Institute and Clinic, Pittsburgh, PA;,To whom correspondence should be addressed; TDH 441, 3811 O’Hara St, Pittsburgh, PA 15213; tel: 412-246-6353, fax: 412-246-6350, e-mail:
| | - Robert H. Yolken
- Stanley Neurovirology Laboratory, Johns Hopkins University, School of Medicine, Baltimore, MD
| |
Collapse
|