gene-expression

Toxoplasma gondii IgG associations with sleep-wake problems, sleep duration and timing

February 1, 2020
Corona, C. C. ,Zhang, M. Wadhawan, A., Daue, M. L., Groer, M. W., Dagdag, A., Lowry, C. A., Hoisington, A. J., Ryan, K. A., Stiller, J. W., Fuchs, D., Mitchell, B. D., Postolache, T. T.
Pteridines 2019, 30: 1 - 9

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Background: Evidence links Toxoplasma gondii (T. gondii), a neurotropic parasite, with schizophrenia, mood disorders and suicidal behavior, all of which are associated and exacerbated by disrupted sleep. Moreover, low-grade immune activation and dopaminergic overstimulation, which are consequences of T. gondii infection, could alter sleep patterns and duration. Methods: Sleep data on 833 Amish participants [mean age (SD) = 44.28 (16.99) years; 59.06% women] were obtained via self-reported questionnaires that assessed sleep problems, duration and timing. T. gondii IgG was measured with ELISA. Data were analyzed using multivariable logistic regressions and linear mixed models, with adjustment for age, sex and family structure. Results: T gondii seropositives reported less sleep problems (p < 0.005) and less daytime problems due to poor sleep (p < 0.005). Higher T. gondii titers were associated with longer sleep duration (p < 0.05), earlier bedtime (p < 0.005) and earlier mid-sleep time (p < 0.05). Conclusions: It seems unlikely that sleep mediates the previously reported associations between gondii and mental illness. Future longitudinal studies with objective measures are necessary to replicate our findings.

Tagged: bipolar disorder, gene-expression, igg, latent toxoplasmosis, mid sleep time, nitric oxide, Parkinson disease, risk factors, sleep duration, sleep timing, suicideattempts, Toxoplasma godnii, traffic accidents, tyrosine- hydroxylase

Behavior Mental health

Neurophysiological changes induced by chronic Toxoplasma gondii infection

December 8, 2017
Tedford, E., McConkey, G.
Pathogens 2017; 6: Artn 19 10.3390/Pathogens6020019

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Although the parasite Toxoplasma gondii is one of the most pervasive neurotropic pathogens in the world, the host-parasite interactions during CNS infection and the consequences of neurological infection are just beginning to be unraveled. The chronic stages of infection have been considered dormant, although several studies have found correlations of infection with an array of host behavioral changes. These may facilitate parasite transmission and impact neurological diseases. During infection, in addition to the presence of the parasites within neurons, host-mediated neuroimmune and hormonal responses to infection are also present. T. gondii induces numerous changes to host neurons during infection and globally alters host neurological signaling pathways, as discussed in this review. Understanding the neurophysiological changes in the host brain is imperative to understanding the parasitic mechanisms and to delineate the effects of this single-celled parasite on health and its contribution to neurological disease

Tagged: alzheimers-disease, bipolar disorder, central-nervous-system, gene-expression, host-parasite interaction, immune system, infection, Neurophysiology, Toxoplasma gondii

Behavior Mental health

Neurophysiological changes induced by chronic Toxoplasma gondii Infection.

March 13, 2017
Tedford, E., McConkey, G.
Pathogens. 2017; 6: 19-31

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Tagged: alzheimers-disease, bipolar disorder, catecholamine, central-nervous-system, dendritic cells, dependent manner, DNA, Dopamine, gamma-interferon, gene-expression, glutamatergic, host-parasite interaction, immune system, infection, methylation, neuroimmune, Neurophysiology, parasitic, testosterone, Toxoplasma gondii

Mental health

Brain development and plasticity

May 25, 2016
Martinez-Morga, M., Martinez, S.
Revista De Neurologia 2016; 62: 3-8

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Neurodevelopmental disorders are associated to functional anomalies of the brain that become manifest early on in life. Traditionally, they have been related almost exclusively to the appearance of intellectual disability and delayed psychomotor development. The causes of these disorders have been partially described, and include anomalies due to genetic causes (Down syndrome, fragile X syndrome, etc.), exposure to toxic factors during pregnancy (foetal alcohol syndrome), infections (cytomegalovirus, toxoplasmosis, etc.) or other alterations, including a status of great immaturity at birth (very preterm). Epidemiological data based on a better knowledge of the diseases affecting the central nervous system suggest that some mental disorders, which appear in adolescence or early adulthood, also have their origin in anomalies in brain development. This review aims to offer an overview of brain development. Some of the cellular and molecular processes that may account for the similarities and differences in the phenotypes that generate alterations affecting normal development are also analysed. The study is conducted with a view to clearly identifying processes that are susceptible to modification by means of therapeutic intervention consisting in an early care programme

Tagged: brain-development, cerebral cortex, cognition, cortical development, disorders, evolution, fgf8, forebrain, gene-expression, malformations, neural migration, neural regionalisation, neuronal migration, Schizophrenia, structural plasticity, synaptogenesis

Cognitive functions Mental health

Toxoplasma gondii seropositivity and cognitive functions in school-aged children

October 6, 2015
Mendy, A., Vieira, E. R., Albatineh, A. N., Gasana, J.
Parasitology 2015; 142: 1221-1227

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Toxoplasma gondii (T. gondii) infects one-third of the world population, but its association with cognitive functions in school-aged children is unclear. We examined the relationship between Toxoplasma seropositivity and neuropsychological tests scores (including math, reading, visuospatial reasoning and verbal memory) in 1755 school-aged children 12-16 years old who participated to the Third National Health and Nutrition Examination Survey, using multiple linear regressions adjusted for covariates. Toxoplasma seroprevalence was 7.7% and seropositivity to the parasite was associated with lower reading skills (regression coefficient [beta] = -5.86, 95% confidence interval [CI]: -11.11, -0.61, P = 0.029) and memory capacities (beta = -0.86, 95% CI: -1.58, -0.15, P = 0.017). The interaction between T. gondii seropositivity and vitamin E significantly correlated with memory scores. In subgroup analysis, Toxoplasma-associated memory impairment was worse in children with lower serum vitamin E concentrations (beta = -1.61, 95% CI: -2.44, -0.77, P < 0.001) than in those with higher values (beta = -0.12, 95% CI: -1.23, 0.99, P = 0.83). In conclusion, Toxoplasma seropositivity may be associated with reading and memory impairments in school-aged children. Serum vitamin E seems to modify the relationship between the parasitic infection and memory deficiency.

Tagged: adults, association, behavior, cognition, cognitive function, disease, Dopamine, gene-expression, infection, intelligence, math, memory, mice, parasites, performance, reading, school-aged children, Toxoplasma gondii, vitamin e, vitamins

Cognitive functions

Masterpiece of epigenetic engineering – how Toxoplasma gondii reprogrammes host brains to change fear to sexual attraction

January 9, 2014
Flegr, J., Markos, A.
Molecular Ecology 2014; 23:5934-5936

Tagged: Dopamine, epigenetics, evolutionary parasitology, fatal attraction, gene-expression, humans, infection, manipulation hypothesis, men, methylation, rats, Schizophrenia, testosterone, toxoplasmosis

Behavior

Toxoplasma gondii antibody titers and history of suicide attempts in patients with schizophrenia

October 16, 2011
Okusaga, O,. Langenberg, P., Sleemi, A., Vaswani, D., Giegling, I., Hartmann, A. M., Konte, B., Friedl, M., Groer, M. W., Yolken, R. H., Rujescu, D., Postolache, T. T.
Schizophrenia Research 2011; 133: 150-155

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Toxoplasma gondii (T. gondii) a widespread neurotropic parasite, has been previously associated with schizophrenia and more recently with suicidal behavior. However, no previous study has examined the association of T. gondii with suicidal behavior in schizophrenia patients. 950 individuals diagnosed with schizophrenia by SCID were recruited from the Munich area of Germany. Solid-enzyme immunoassay methods were used to measure IgG plasma antibodies to T. gondii, other neurotropic pathogens and gliadin. Logistic regression models were developed to analyze the association of T. gondii seropositivity or serointensity with history of suicidal behavior. In those younger than the median age of the sample, 38, T. gondii serointensity was associated with history of suicidal behavior (p = 0.02), while in the older patients the relationship was not significant (p = 0.21). Seropositivity was also associated with history of suicide attempt in younger patients, odds ratio 1.59 (95% CI 1.06 to 2.40), p = 0.03. Seropositivity for CMV (p = 0.22), HSV-1 (p = 0.36) and gliadin (p = 0.92) was not related to history of suicide attempt in the entire sample or any age subgroup. T. gondii serology might become, with interaction with vulnerability genes, a candidate biomarker for a subgroup of schizophrenia patients prone to attempting suicide

Tagged: behavior, Cerebral toxoplasmosis, endophenotypes, gene-expression, infection, kynurenic acid, lifetime risk, psychosis, reactivation, Schizophrenia, suicidal-behavior, Toxoplasma gondii, united-states

Behavior Mental health

Potential solutions to problems posed by the offspring sex ratios of people with parasitic and viral infections

January 8, 2010
James, W. H.
Folia Parasitologica 2010; 57:114-120

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I have hypothesized that mammalian offspring sex ratios (proportions male at birth) are partially controlled by the hormone levels of both parents around the time of conception. Recently data have been published (privately) which impugn suggestions of mine (based on that hypothesis) relating to the offspring sex ratios of people who are carriers of hepatitis B virus; and (publicly) to hormone profiles of women who are infected with the protozoan parasite Toxoplasma gondii. Here these data are reviewed in the light of data on offspring sex ratios of people infected with hepatitis C, and cytomegalovirus and T gondii; and of mice with T gondii and the trichostrongyline nematode Heligmosomoides polygyrus. Three proposals are made viz: I. Women infected with T gondii may have high oestrogen levels. This would potentially explain reports of their high offspring sex ratios, long gestations and (perhaps) behavioural traits. 2. Some of these infective organisms may 'prefer' a particular endocrine environment in their host (in the sense that it facilitates replication or transmission or both). 3. Some of these organisms apparently cause changes in that endocrine environment as a consequence of their presence. If both the latter two proposals were correct, it could explain recent puzzling data on the offspring sex ratios of hepatitis B carriers. And if this solution turns out to be correct, it would suggest new endocrine means of combating hepatitis B infection.

Tagged: 4th digit ratio, chronic murine toxoplasmosis, cytomegalovirus cmv, gene-expression, heligmosomoides polygyrus, hepatitis b virus hbv, hepatitis c virus hcv, hepatitis-b-virus, hepatocellular-carcinoma, latent asymptomatic toxoplasmosis, ovarian dysfunction, parental hormone-levels, serum testosterone, sex ratio at birth, testosterone concentration, Toxoplasma gondii

Reproduction

Toxoplasma gondii & Human Phenotype

Compendium of Known Effects and Ongoing Research

gene-expression

Toxoplasma gondii IgG associations with sleep-wake problems, sleep duration and timing

Neurophysiological changes induced by chronic Toxoplasma gondii infection

Neurophysiological changes induced by chronic Toxoplasma gondii Infection.

Brain development and plasticity

Toxoplasma gondii seropositivity and cognitive functions in school-aged children

Masterpiece of epigenetic engineering – how Toxoplasma gondii reprogrammes host brains to change fear to sexual attraction

Toxoplasma gondii antibody titers and history of suicide attempts in patients with schizophrenia

Potential solutions to problems posed by the offspring sex ratios of people with parasitic and viral infections