simplex-virus type-1

Temporal cognitive decline associated with exposure to infectious agents in a population-based, aging cohort

October 29, 2016
Nimgaonkar, V. L., Yolken, R. H., Wang, T. X., Chang, C. C. H., McClain, L., McDade, E., Snitz, B. E., Ganguli, M
Alzheimer Disease & Associated Disorders 2016; 30: 216-222

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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.

Tagged: aging, antibodies, bipolar disorder, CMV, cognition, community, cytomegalovirus, disease, Epidemiology, herpes virus, impairment, persistent infection, Schizophrenia, simplex-virus type-1, Toxoplasma gondii, viral-infections

Cognitive functions

Infectious disease burden and cognitive function in young to middle-aged adults

January 4, 2016
Gale, S. D., Erickson, L. D., Berrett, A., Brown, B. L., Hedges, D. W.
Brain Behavior and Immunity 2016, 52: 161-168

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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. (C) 2015 Elsevier Inc. All rights reserved.

Tagged: 3rd national-health, chronic hepatitis-c, cytomegalovirus, cytomegalovirus-infection, hepatitis, herpes, infectious disease, latent toxoplasmosis, neurocognitive function, nhanes, northern-manhattan, nutrition examination survey, risk factors, simplex-virus type-1, toxocariasis, toxoplasma gondii infection, toxoplasmosis, united-states

Cognitive functions

Cognitive deterioration among bipolar disorder patients infected by Toxoplasma gondii is correlated to interleukin 6 levels

October 6, 2015
Hamdani, N., Daban-Huard, C., Lajnef, M., Gadel, R., Le Corvoisier, P., Delavest, M., Carde, S., Lepine, J. P., Jamain, S., Houenou, J., Galeh, B., Richard, J. R., Aoki, M., Charron, D., Krishnamoorthy, R., Yolken, R., Dickerson, F., Tamouza, R., Leboyer, M.
Journal of Affective Disorders 2015; 179: 161-166

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Background: Cognitive deficits are present in a large majority of Bipolar Disorder (BD) patients and known to be a marker of bad prognosis. Because, these deficits encompass several domains and no specific medical treatment seems to be effective, it is important to better understand the mechanisms underlying cognitive deterioration. As Toxoplasma gondii is known to induce the synthesis of pro-inflammatory cytokines such as IL-6, we will explore here the possible role of T. gondii in the cognitive decline observed in BD. Methods: 42 euthymic BD patients and 36 controls were assessed for episodic verbal memory using the CVLT and for working memory and verbal ability using the WAIS Ill. Patients and controls were also screened for seropositivity to I gondii and evaluated for the levels of IL-fl transcripts. Results: The seropositivity for I gondii was significantly higher in BD patients as compared to controls (p-0.005). The cognitive deterioration index (Dl) was higher in BD patients (p=5.10 ') and correlated to high IL-6 mRNA expression only among those infected by T gondii (rho-0.43, p-0.01). Among deteriorated patients (defined by scores above 0.10 according to Weschler's definition), the IL-6 mRNA expression was twice greater (p=0.01). Limitations: Our results are to be interpreted with caution because of our small sample size and the cross-sectional design. Conclusions: A long-term exposure to inflammation, measured here with IL-6 mRNA expression in T. gonciii infected BD may alter cognitive functioning. IL-6 could thus be a useful predictive marker of cognitive deterioration in BD and may help to design personalized treatment.

Tagged: antibodies, association, bipolar disorder, cognitive deterioration, exposure, il-6, impairment, individuals, Major depression, risk, Schizophrenia, simplex-virus type-1, t. gondii, traffic accidents

Cognitive functions Mental health

An observational study of inflammation in the central nervous system in patients with bipolar disorder

January 5, 2015
Stich, O., Andres, T. A., Gross, C. M., Gerber, S. I., Rauer, S., Langosch, J. M.
Bipolar Disorders 2015; 17: 291-302

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ObjectivesThe potential influence of infections and immunological changes on the aetiology and pathogenesis of bipolar disorder (BD) has been discussed. Our aim was to detect intrathecal specific antibody synthesis against the neurotropic infectious agents that have previously been linked to BD. MethodsPaired cerebrospinal fluid (CSF) and serum samples from 40 patients with BD were analysed using the enzyme-linked immunosorbent assay to detect the concentration of antibodies against the following neurotropic infectious pathogens: Toxoplasma gondii (T.gondii), herpes simplex virus (HSV) types 1 and 2, cytomegalovirus (CMV), and Epstein-Barr virus (EBV). The specific antibody index (AI) was calculated, and an AI>1.4 was considered to be evidence of intrathecal specific antibody synthesis. Twenty-six patients with pseudotumour cerebri served as controls. ResultsEight out of 40 patients with BD displayed specific intrathecal antibody synthesis against at least one of the tested neurotropic agents compared to only one patient in the control group (p=0.061, not significant). Of these eight patients with BD, no significant prevalence of any particular neurotropic pathogen was evident. Five out of 40 patients with BD showed oligoclonal bands in the CSF, suggestive of a chronic immune reaction in the central nervous system (CNS). ConclusionsWe found evidence for increased production of antibody in the CSF of individuals with BD. However, the trend for polyspecific intrathecal antibody synthesis, as well as the presence of oligoclonal bands, might indicate activation of the intrathecal humoral immune system in a subgroup of patients with BD, as it is known to be associated with autoimmune disorders of the CNS.

Tagged: agents, antibodies, antibody index, autoimmunity, bipolar disorder, cerebrospinal fluid, cognitive deficits, cytomegalovirus, disease, epstein-barr-virus, herpes-simplex, herpesviridae, infection, intrathecal synthesis, networks, neurotropic agents, psychosis, Schizophrenia, simplex-virus type-1, Toxoplasma gondii, toxoplasma gondii infection

Mental health

Antibodies to Toxoplasma gondii and cognitive functioning in schizophrenia, bipolar disorder, and nonpsychiatric controls

October 9, 2014
Dickerson, F., Stallings, C., Origoni, A., Katsafanas, E., Schweinfurth, L., Savage, C., Khushalani, S,. Yolken, R.
Journal of Nervous and Mental Disease 2014; 202: 589-593

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Increased rates of exposure to Toxoplasma gondii have been found in individuals with schizophrenia and bipolar disorder, but the association between Toxoplasma and cognitive functioning has not previously been examined. We measured IgG and IgM class antibodies to Toxoplasma in 408 nonelderly individuals with schizophrenia, 347 with bipolar disorder, and 352 nonpsychiatric controls. Cognitive functioning was measured with the Repeatable Battery for the Assessment of Neuropsychological Status. Multivariate linear and regression analyses showed significant associations between Toxoplasma IgM antibody level and cognitive scores within the control group and the bipolar disorder group but not the schizophrenia group. Within the control group, having an elevated Toxoplasma IgM antibody level, greater than or equal to the 50th and 75th levels of the control group, was associated with significantly elevated odds of a low total cognitive score. Exposure to Toxoplasma may confer risk for lower cognitive functioning in persons without a psychiatric disorder and those with bipolar disorder.

Tagged: agents, bipolar disorder, cognition, deficits, impairment, infection, Parasite, Schizophrenia, simplex-virus type-1, Toxoplasma gondii

Cognitive functions Mental health

Infectious agents and gene-environmental interactions in the etiopathogenesis of schizophrenia

October 30, 2006
Yolken RH, Torrey EF
Clinical Neuroscience Research 2006; 6: 97-109.

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Schizophrenia is a pervasive neuropsychiatric disorder with worldwide prevalence. Family and adoption studies indicate a strong genetic component of disease susceptibility. However, epidemiological studies also point to a role for infections and other environmental factors in disease etiology. We review the evidence for a role for infectious agents in the etiopathogenesis of schizophrenia and related disorders, focusing on the apicomplexan parasite Toxoplasma gondii. We discuss the epidemiological evidence for a role for this agent, as well as potential mechanisms of gene-environmental interactions which are consistent with the genetic components of disease susceptibility. We describe how the potential role of infections as causative agents of complex disorders such as schizophrenia are not consistent with classical postulates of causation such as the Koch Postulates, but may be consistent with more modern concepts of how infectious agents can interact with genetic determinants to result in disease in susceptible individuals. We outline the research approaches which are necessary to define associations between infectious agents and complex disorders. The successful association between infectious agents and diseases such as schizophrenia might lead to new methods for treatment and prevention of these devastating disorders. (C) 2006 Association for Research in Nervous and Mental Disease. Published by Elsevier B.V. All rights reserved.

Tagged: adult schizophrenia, bipolar disorder, etiopathogenesis, helicobacter-pylori-infection, human endogenous retroviruses, in-vivo, nervous-system infections, recent-onset schizophrenia, Schizophrenia, simplex-virus type-1, Toxoplasma gondii, viral encephalitis

Mental health

Infectious agents and gene-environmental interactions in the etiopathogenesis of schizophrenia

March 26, 2006
Yolken, R. H., Torrey, E. F.
Clinical Neuroscience Research 2006; 6: 97-109

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Mental health

Toxoplasma gondii & Human Phenotype

Compendium of Known Effects and Ongoing Research

simplex-virus type-1

Temporal cognitive decline associated with exposure to infectious agents in a population-based, aging cohort

Infectious disease burden and cognitive function in young to middle-aged adults

Cognitive deterioration among bipolar disorder patients infected by Toxoplasma gondii is correlated to interleukin 6 levels

An observational study of inflammation in the central nervous system in patients with bipolar disorder

Antibodies to Toxoplasma gondii and cognitive functioning in schizophrenia, bipolar disorder, and nonpsychiatric controls

Infectious agents and gene-environmental interactions in the etiopathogenesis of schizophrenia

Infectious agents and gene-environmental interactions in the etiopathogenesis of schizophrenia