Resting-state fMRI is associated with trauma experiences, mood and psychosis in Afro-descendants with bipolar disorder and schizophrenia.

BACKGROUND: Bipolar disorder (BD) and schizophrenia (SCZ) may exhibit functional abnormalities in several brain areas, including the medial temporal and prefrontal cortex and hippocampus; however, a less explored topic is how brain connectivity is linked to premorbid trauma experiences and clinical features in non-Caucasian samples of SCZ and BD. METHODS: Sixty-two individuals with SCZ (n = 20), BD (n = 21), and healthy controls (HC, n = 21) from indigenous and African ethnicity were submitted to clinical screening (Di-PAD), traumata experiences (ETISR-SF), cognitive and functional MRI assessment. The item psychosis/hallucinations in SCZ patients showed a negative correlation with the global efficiency (GE) in the right dorsal attention network. The items mania, irritable mood, and racing thoughts in the Di-PAD scale had a significant negative correlation with the GE in the parietal right default mode network. CONCLUSIONS: Differences in the activation of specific networks were associated with earlier disease onset, history of physical abuse, and more severe psychotic and mood symptoms in SCZ and BD subjects of indigenous and black ethnicity. Findings provide further evidence on SZ and BD's brain connectivity disturbances, and their clinical significance, in non-Caucasian samples.

Non-binary gender, vulnerable populations and mental health during the COVID-19 pandemic: Data from the COVID-19 MEntal health inTernational for the general population (COMET-G) study.

BACKGROUND: The COVID-19 pandemic has brought significant mental health challenges, particularly for vulnerable populations, including non-binary gender individuals. The COMET international study aimed to investigate specific risk factors for clinical depression or distress during the pandemic, also in these special populations. METHODS: Chi-square tests were used for initial screening to select only those variables which would show an initial significance. Risk Ratios (RR) were calculated, and a Multiple Backward Stepwise Linear Regression Analysis (MBSLRA) was followed with those variables given significant results at screening and with the presence of distress or depression or the lack of both of them. RESULTS: The most important risk factors for depression were female (RR = 1.59-5.49) and non-binary gender (RR = 1.56-7.41), unemployment (RR = 1.41-6.57), not working during lockdowns (RR = 1.43-5.79), bad general health (RR = 2.74-9.98), chronic somatic disorder (RR = 1.22-5.57), history of mental disorders (depression RR = 2.31-9.47; suicide attempt RR = 2.33-9.75; psychosis RR = 2.14-10.08; Bipolar disorder RR = 2.75-12.86), smoking status (RR = 1.15-5.31) and substance use (RR = 1.77-8.01). The risk factors for distress or depression that survived MBSLRA were younger age, being widowed, living alone, bad general health, being a carer, chronic somatic disorder, not working during lockdowns, being single, self-reported history of depression, bipolar disorder, self-harm, suicide attempts and of other mental disorders, smoking, alcohol, and substance use. CONCLUSIONS: Targeted preventive interventions are crucial to safeguard the mental health of vulnerable groups, emphasizing the importance of diverse samples in future research. LIMITATIONS: Online data collection may have resulted in the underrepresentation of certain population groups.

Sex and the Estrous-Cycle Phase Influence the Expression of G Protein-Coupled Estrogen Receptor 1 (GPER) in Schizophrenia: Translational Evidence for a New Target.

Schizophrenia is a mental disorder with sex bias in disease onset and symptom severity. Recently, it was observed that females present more severe symptoms in the perimenstrual phase of the menstrual cycle. The administration of estrogen also alleviates schizophrenia symptoms. Despite this, little is known about symptom fluctuation over the menstrual cycle and the underlying mechanisms. To address this issue, we worked with the two-hit schizophrenia animal model induced by neonatal exposure to a virus-like particle, Poly I:C, associated with peripubertal unpredictable stress exposure. Prepulse inhibition of the startle reflex (PPI) in male and female mice was considered analogous to human schizophrenia-like behavior. Female mice were studied in the proestrus (high-estrogen estrous cycle phase) and diestrus (low-estrogen phase). Additionally, we evaluated the hippocampal mRNA expression of estrogen synthesis proteins; TSPO and aromatase; and estrogen receptors ERα, ERß, and GPER. We also collected peripheral blood mononuclear cells (PBMCs) from male and female patients with schizophrenia and converted them to induced microglia-like cells (iMGs) to evaluate the expression of GPER. We observed raised hippocampal expression of GPER in two-hit female mice at the proestrus phase without PPI deficits and higher levels of proteins related to estrogen synthesis, TSPO, and aromatase. In contrast, two-hit adult males with PPI deficits presented lower hippocampal mRNA expression of TSPO, aromatase, and GPER. iMGs from male and female patients with schizophrenia showed lower mRNA expression of GPER than controls. Therefore, our results suggest that GPER alterations constitute an underlying mechanism for sex influence in schizophrenia.

Results of the COVID-19 mental health international for the health professionals (COMET-HP) study: depression, suicidal tendencies and conspiracism.

INTRODUCTION: The current study aimed to investigate the rates of anxiety, clinical depression, and suicidality and their changes in health professionals during the COVID-19 outbreak. MATERIALS AND METHODS: The data came from the larger COMET-G study. The study sample includes 12,792 health professionals from 40 countries (62.40% women aged 39.76 ± 11.70; 36.81% men aged 35.91 ± 11.00 and 0.78% non-binary gender aged 35.15 ± 13.03). Distress and clinical depression were identified with the use of a previously developed cut-off and algorithm, respectively. STATISTICAL ANALYSIS: Descriptive statistics were calculated. Chi-square tests, multiple forward stepwise linear regression analyses, and Factorial Analysis of Variance (ANOVA) tested relations among variables. RESULTS: Clinical depression was detected in 13.16% with male doctors and 'non-binary genders' having the lowest rates (7.89 and 5.88% respectively) and 'non-binary gender' nurses and administrative staff had the highest (37.50%); distress was present in 15.19%. A significant percentage reported a deterioration in mental state, family dynamics, and everyday lifestyle. Persons with a history of mental disorders had higher rates of current depression (24.64% vs. 9.62%; p < 0.0001). Suicidal tendencies were at least doubled in terms of RASS scores. Approximately one-third of participants were accepting (at least to a moderate degree) a non-bizarre conspiracy. The highest Relative Risk (RR) to develop clinical depression was associated with a history of Bipolar disorder (RR = 4.23). CONCLUSIONS: The current study reported findings in health care professionals similar in magnitude and quality to those reported earlier in the general population although rates of clinical depression, suicidal tendencies, and adherence to conspiracy theories were much lower. However, the general model of factors interplay seems to be the same and this could be of practical utility since many of these factors are modifiable.

Clozapine prescription trends in Brazil in the last decade

Objective: Clozapine is a second-generation antipsychotic indicated for treatment-resistant schizophrenia. Studies in several countries have shown a low rate of clozapine use despite the fact that approximately 30% of schizophrenia cases are treatment-resistant. In Brazil, few studies have addressed the frequency and variety of antipsychotic use in individuals diagnosed with schizophrenia (ICD F20). The objective of this study was to measure the rates of clozapine use in this population in the last decade using Brazilian Ministry of Health data. Methods: Prescriptions made between 2010 and 2020 in all 26 states and the Federal District registered at the Outpatient Information System Database from the Brazilian Health System (SIASUS) were evaluated. Results: A total of 25,143,524 prescriptions were recorded in this period, with clozapine representing 8.86% of all antipsychotics. The most frequently prescribed antipsychotic for patients with schizophrenia was olanzapine (35.8%), followed by quetiapine (27.5%). From 2010 to 2020, the rate of clozapine prescriptions in Brazil increased from 7.2% to 10.9%. Conclusions: Despite a slight increase in prescriptions in the last decade, clozapine is still underutilized in Brazil.

Clozapine prescription trends in Brazil in the last decade.

OBJECTIVE: Clozapine is a second-generation antipsychotic indicated for treatment-resistant schizophrenia. Studies in several countries have shown a low rate of clozapine use despite the fact that approximately 30% of schizophrenia cases are treatment-resistant. In Brazil, few studies have addressed the frequency and variety of antipsychotic use in individuals diagnosed with schizophrenia (ICD F20). The objective of this study was to measure the rates of clozapine use in this population in the last decade using Brazilian Ministry of Health data. METHODS: Prescriptions made between 2010 and 2020 in all 26 states and the Federal District registered at the Outpatient Information System Database from the Brazilian Health System (SIASUS) were evaluated. RESULTS: A total of 25,143,524 prescriptions were recorded in this period, with clozapine representing 8.86% of all antipsychotics. The most frequently prescribed antipsychotic for patients with schizophrenia was olanzapine (35.8%), followed by quetiapine (27.5%). From 2010 to 2020, the rate of clozapine prescriptions in Brazil increased from 7.2% to 10.9%. CONCLUSIONS: Despite a slight increase in prescriptions in the last decade, clozapine is still underutilized in Brazil.

The effect of different degrees of lockdown and self-identified gender on anxiety, depression and suicidality during the COVID-19 pandemic: Data from the international COMET-G study.

INTRODUCTION: During the COVID-19 pandemic various degrees of lockdown were applied by countries around the world. It is considered that such measures have an adverse effect on mental health but the relationship of measure intensity with the mental health effect has not been thoroughly studied. Here we report data from the larger COMET-G study pertaining to this question. MATERIAL AND METHODS: During the COVID-19 pandemic, data were gathered with an online questionnaire from 55,589 participants from 40 countries (64.85% females aged 35.80 ± 13.61; 34.05% males aged 34.90±13.29 and 1.10% other aged 31.64±13.15). Anxiety was measured with the STAI, depression with the CES-D and suicidality with the RASS. Distress and probable depression were identified with the use of a previously developed cut-off and algorithm respectively. STATISTICAL ANALYSIS: It included the calculation of Relative Risk (RR), Factorial ANOVA and Multiple backwards stepwise linear regression analysis RESULTS: Approximately two-thirds were currently living under significant restrictions due to lockdown. For both males and females the risk to develop clinical depression correlated significantly with each and every level of increasing lockdown degree (RR 1.72 and 1.90 respectively). The combined lockdown and psychiatric history increased RR to 6.88 The overall relationship of lockdown with severity of depression, though significant was small. CONCLUSIONS: The current study is the first which reports an almost linear relationship between lockdown degree and effect in mental health. Our findings, support previous suggestions concerning the need for a proactive targeted intervention to protect mental health more specifically in vulnerable groups.

Animal Model of Neonatal Immune Challenge by Lipopolysaccharide: A Study of Sex Influence in Behavioral and Immune/Neurotrophic Alterations in Juvenile Mice.

INTRODUCTION: The prenatal/perinatal exposure to infections may trigger neurodevelopmental alterations that lead to neuropsychiatric disorders such as autism spectrum disorder (ASD). Previous evidence points to long-term behavioral consequences, such as autistic-like behaviors in rodents induced by lipopolysaccharide (LPS) pre- and postnatal (PN) exposure during critical neurodevelopmental periods. Additionally, sex influences the prevalence and symptoms of ASD. Despite this, the mechanisms underlying this influence are poorly understood. We aim to study sex influences in behavioral and neurotrophic/inflammatory alterations triggered by LPS neonatal exposure in juvenile mice at an approximate age of ASD diagnosis in humans. METHODS: Swiss male and female mice on PN days 5 and 7 received a single daily injection of 500 µg/kg LPS from Escherichia coli or sterile saline (control group). We conducted behavioral determinations of locomotor activity, repetitive behavior, anxiety-like behavior, social interaction, and working memory in animals on PN25 (equivalent to 3-5 years old of the human). To determine BDNF levels in the prefrontal cortex and hippocampus, we used animals on PN8 (equivalent to a human term infant) and PN25. In addition, we evaluated iba-1 (microglia marker), TNFα, and parvalbumin expression on PN25. RESULTS: Male juvenile mice presented repetitive behavior, anxiety, and working memory deficits. Females showed social impairment and working memory deficits. In the neurochemical analysis, we detected lower BDNF levels in brain areas of female mice that were more evident in juvenile mice. Only LPS-challenged females presented a marked hippocampal expression of the microglial activation marker, iba-1, and increased TNFα levels, accompanied by a lower parvalbumin expression. DISCUSSION/CONCLUSION: Male and female mice presented distinct behavioral alterations. However, LPS-challenged juvenile females showed the most prominent neurobiological alterations related to autism, such as increased microglial activation and parvalbumin impairment. Since these sex-sensitive alterations seem to be age-dependent, a better understanding of changes induced by the exposure to specific risk factors throughout life represents essential targets for developing strategies for autism prevention and precision therapy.

Results of the COVID-19 mental health international for the general population (COMET-G) study.

INTRODUCTION: There are few published empirical data on the effects of COVID-19 on mental health, and until now, there is no large international study. MATERIAL AND METHODS: During the COVID-19 pandemic, an online questionnaire gathered data from 55,589 participants from 40 countries (64.85% females aged 35.80 ± 13.61; 34.05% males aged 34.90±13.29 and 1.10% other aged 31.64±13.15). Distress and probable depression were identified with the use of a previously developed cut-off and algorithm respectively. STATISTICAL ANALYSIS: Descriptive statistics were calculated. Chi-square tests, multiple forward stepwise linear regression analyses and Factorial Analysis of Variance (ANOVA) tested relations among variables. RESULTS: Probable depression was detected in 17.80% and distress in 16.71%. A significant percentage reported a deterioration in mental state, family dynamics and everyday lifestyle. Persons with a history of mental disorders had higher rates of current depression (31.82% vs. 13.07%). At least half of participants were accepting (at least to a moderate degree) a non-bizarre conspiracy. The highest Relative Risk (RR) to develop depression was associated with history of Bipolar disorder and self-harm/attempts (RR = 5.88). Suicidality was not increased in persons without a history of any mental disorder. Based on these results a model was developed. CONCLUSIONS: The final model revealed multiple vulnerabilities and an interplay leading from simple anxiety to probable depression and suicidality through distress. This could be of practical utility since many of these factors are modifiable. Future research and interventions should specifically focus on them.

Bipolar disorder: an association between body mass index and cingulate gyrus fractional anisotropy not mediated by systemic inflammation.

OBJECTIVE: To investigate associations between body mass index (BMI), white matter fractional anisotropy (FA), and C-reactive protein (CRP) in a group of individuals with bipolar disorder (BD) during euthymia and compare them with a control group of healthy subjects (CTR). METHODS: The sample consisted of 101 individuals (BD n = 35 and CTR n = 66). Regions of interest (ROI) were defined using a machine learning approach. For each ROI, a regression model tested the association between FA and BMI, controlling for covariates. Peripheral CRP levels were assayed, correlated with BMI, and included in a mediation analysis. RESULTS: BMI predicted the FA of the right cingulate gyrus in BD (AdjR2 = 0.312 F(3) = 5.537 p = 0.004; ß = -0.340 p = 0.034), while there was no association in CTR. There was an interaction effect between BMI and BD diagnosis (F(5) = 3.5857 p = 0.012; Fchange = 0.227 AdjR2 = 0.093; ß = -1.093, p = 0.048). Furthermore, there was a positive correlation between BMI and CRP in both groups (AdjR2 = 0.170 F(3) = 7.337 p < 0.001; ß = 0.364 p = 0.001), but it did not act as a mediator of the effect on FA. CONCLUSION: Higher BMI is associated with right cingulate microstructure in BD, but not in CTR, and this effect could not be explained by inflammatory mediation alone.

Bipolar disorder: an association between body mass index and cingulate gyrus fractional anisotropy not mediated by systemic inflammation

Abstract Objective To investigate associations between body mass index (BMI), white matter fractional anisotropy (FA), and C-reactive protein (CRP) in a group of individuals with bipolar disorder (BD) during euthymia and compare them with a control group of healthy subjects (CTR). Methods The sample consisted of 101 individuals (BD n = 35 and CTR n = 66). Regions of interest (ROI) were defined using a machine learning approach. For each ROI, a regression model tested the association between FA and BMI, controlling for covariates. Peripheral CRP levels were assayed, correlated with BMI, and included in a mediation analysis. Results BMI predicted the FA of the right cingulate gyrus in BD (AdjR2 = 0.312 F(3) = 5.537 p = 0.004; β = -0.340 p = 0.034), while there was no association in CTR. There was an interaction effect between BMI and BD diagnosis (F(5) = 3.5857 p = 0.012; Fchange = 0.227 AdjR2 = 0.093; β = -1.093, p = 0.048). Furthermore, there was a positive correlation between BMI and CRP in both groups (AdjR2 = 0.170 F(3) = 7.337 p < 0.001; β = 0.364 p = 0.001), but it did not act as a mediator of the effect on FA. Conclusion Higher BMI is associated with right cingulate microstructure in BD, but not in CTR, and this effect could not be explained by inflammatory mediation alone.

Involvement of anti-inflammatory, antioxidant, and BDNF up-regulating properties in the antipsychotic-like effect of the essential oil of Alpinia zerumbet in mice: a comparative study with olanzapine.

The current drug therapy for schizophrenia effectively treats acute psychosis and its recurrence; however, this mental disorder's cognitive and negative symptoms are still poorly controlled. Antipsychotics present important side effects, such as weight gain and extrapyramidal effects. The essential oil of Alpinia zerumbet (EOAZ) leaves presents potential antipsychotic properties that need further preclinical investigation. Here, we determined EAOZ effects in preventing and reversing schizophrenia-like symptoms (positive, negative, and cognitive) induced by ketamine (KET) repeated administration in mice and putative neurobiological mechanisms related to this effect. We conducted the behavioral evaluations of prepulse inhibition of the startle reflex (PPI), social interaction, and working memory (Y-maze task), and verified antioxidant (GSH, nitrite levels), anti-inflammatory [interleukin (IL)-6], and neurotrophic [brain-derived neurotrophic factor (BDNF)] effects of this oil in hippocampal tissue. The atypical antipsychotic olanzapine (OLZ) was used as standard drug therapy. EOAZ, similarly to OLZ, prevented and reversed most KET-induced schizophrenia-like behavioral alterations, i.e., sensorimotor gating deficits and social impairment. EOAZ had a modest effect on the prevention of KET-associated working memory deficit. Compared to OLZ, EOAZ showed a more favorable side effects profile, inducing less cataleptic and weight gain changes. EOAZ efficiently protected the hippocampus against KET-induced oxidative imbalance, IL-6 increments, and BDNF impairment. In conclusion, our data add more mechanistic evidence for the anti-schizophrenia effects of EOAZ, based on its antioxidant, anti-inflammatory, and BDNF up-regulating actions. The absence of significant side effects observed in current antipsychotic drug therapy seems to be an essential benefit of the oil.

Low-dose candesartan prevents schizophrenia-like behavioral alterations in a neurodevelopmental two-hit model of schizophrenia.

Schizophrenia is a severe mental disorder with complex etiopathogenesis. Based on its neurodevelopmental features, an animal model induced by "two-hit" based on perinatal immune activation followed by peripubertal unpredictable stress was proposed. Sex influences the immune response, and concerning schizophrenia, it impacts the age of onset and symptoms severity. The neurobiological mechanisms underlying the influence of sex in schizophrenia is poorly understood. Our study aimed to evaluate sex influence on proinflammatory and oxidant alterations in male and female mice exposed to the two-hit model of schizophrenia, and its prevention by candesartan, an angiotensin II type 1 receptor (AT1R) blocker with neuroprotective properties. The two-hit model induced schizophrenia-like behavioral changes in animals of both sexes. Hippocampal microglial activation alongside the increased expression of NF-κB, and proinflammatory cytokines, namely interleukin (IL)-1ß and TNF-α, were observed in male animals. Conversely, females presented increased hippocampal and plasma levels of nitrite and plasma lipid peroxidation. Peripubertal administration of low-dose candesartan (0.3 mg/kg PO) prevented behavioral, hippocampal, and systemic changes in male and female mice. While these results indicate the influence of sex on inflammatory and oxidative changes induced by the two-hit model, candesartan was effective in both males and females. The present study advances the neurobiological mechanisms underlying sex influence in schizophrenia and opens new avenues to prevent this devasting mental disorder.

Antidepressants of different classes cause distinct behavioral and brain pro- and anti-inflammatory changes in mice submitted to an inflammatory model of depression.

BACKGROUND: Depressed patients present increased plasma levels of lipopolysaccharide (LPS) and neuroinflammatory alterations. Here, we determined the neuroimmune effects of different classes of ADs by using the LPS inflammatory model of depression. METHODS: Male rats received amitriptyline (AMI) a tricyclic, S-citalopram (ESC) a selective serotonin reuptake inhibitor, tranylcypromine (TCP) a monoamine oxidase inhibitor, vortioxetine (VORT) a multimodal AD or saline for ten days. One-hour after the last AD administration, rats were exposed to LPS 0.83 mg/kg or saline and 24 h later were tested for depressive-like behavior. Plasma corticosterone, brain levels of nitrite, pro- and anti-inflammatory cytokines, phospho-cAMP Response Element-Binding Protein (CREB) and nuclear factor (NF)-kB p 65 were determined. RESULTS: LPS induced despair-like, impaired motivation/self-care behavior and caused anhedonia. All ADs prevented LPS-induced despair-like behavior, but only VORT rescued impaired self-care behavior. All ADs prevented LPS-induced increase in brain pro-inflammatory cytokines [interleukin (IL)-1ß and IL-6] and T-helper 1 cytokines [tumor necrosis factor (TNF)-α and interferon-γ]. VORT increased striatal and hypothalamic IL-4 levels. All ADs prevented LPS-induced neuroendocrine alterations represented by increased levels of hypothalamic nitrite and plasma corticosterone response. VORT and ESC prevented LPS-induced increase in NF-kBp65 hippocampal expression, while ESC, TCP and VORT, but not IMI, prevented the alterations in phospho-CREB expression. LIMITATIONS: LPS model helps to understand depression in a subset of depressed patients with immune activation. The levels of neurotransmitters were not determined. CONCLUSION: This study provides new evidence for the immunomodulatory effects of ADs, and shows a possible superior anti-inflammatory profile of TCP and VORT.

The GLP-1 receptor agonist liraglutide reverses mania-like alterations and memory deficits induced by D-amphetamine and augments lithium effects in mice: Relevance for bipolar disorder.

Metabolic and psychiatric disorders present a bidirectional relationship. GLP-1 system, known for its insulinotropic effects, has also been associated with numerous regulatory effects in cognitive and emotional processing. GLP-1 receptors (GLP-1R) agonists present neuroprotective and antidepressant/anxiolytic properties. However, the effects of GLP-1R agonism in bipolar disorder (BD) mania and the related cognitive disturbances remains unknown. Here, we investigated the effects of the GLP-1R agonist liraglutide (LIRA) at monotherapy or combined with lithium (Li) against D-amphetamine (AMPH)-induced mania-like symptoms, brain oxidative and BDNF alterations in mice. Swiss mice received AMPH 2 mg/kg or saline for 14 days. Between days 8-14, they received LIRA 120 or 240 µg/kg, Li 47.5 mg/kg or the combination Li + LIRA, on both doses. After behavioral evaluation the brain areas prefrontal cortex (PFC), hippocampus and amygdala were collected. AMPH induced hyperlocomotion, risk-taking behavior and multiple cognitive deficits which resemble mania. LIRA reversed AMPH-induced hyperlocomotion, working and recognition memory impairments, while Li + LIRA240 rescued all behavioral changes induced by AMPH. LIRA reversed AMPH-induced hippocampal oxidative and neurotrophic changes. Li + LIRA240 augmented Li antioxidant effects and greatly reversed AMPH-induced BDNF changes in PFC and hippocampus. LIRA rescued the weight gain induced by Li in the course of mania model. Therefore, LIRA can reverse some mania-like behavioral alterations and combined with Li augmented the mood stabilizing and neuroprotective properties of Li. This study points to LIRA as a promising adjunctive tool for BD treatment and provides the first rationale for the design of clinical trials investigating its possible antimanic effect.

Sex influences in the preventive effects of N-acetylcysteine in a two-hit animal model of schizophrenia.

BACKGROUND: Schizophrenia (SCZ) is a neurodevelopmental disorder influenced by patient sex. Mechanisms underlying sex differences in SCZ remain unknown. A two-hit model of SCZ combines the exposure to perinatal infection (first-hit) with peripubertal unpredictable stress (PUS, second-hit). N-acetylcysteine (NAC) has been tested in SCZ because of the involvement of glutathione mechanisms in its neurobiology. AIMS: We aim to investigate whether NAC administration to peripubertal rats of both sexes could prevent behavioral and neurochemical changes induced by the two-hit model. METHODS: Wistar rats were exposed to polyinosinic:polycytidylic acid (a viral mimetic) or saline on postnatal days (PND) 5-7. On PND30-59 they received saline or NAC 220 mg/kg and between PND40-48 were subjected to PUS or left undisturbed. On PND60 behavioral and oxidative alterations were evaluated in the prefrontal cortex (PFC) and striatum. Mechanisms of hippocampal memory regulation such as immune expression of G protein-coupled estrogen receptor 1 (GPER), α7-nAChR and parvalbumin were also evaluated. RESULTS: NAC prevented sensorimotor gating deficits only in females, while it prevented alterations in social interaction, working memory and locomotor activity in both sexes. Again, in rats of both sexes, NAC prevented the following neurochemical alterations: glutathione (GSH) and nitrite levels in the PFC and lipid peroxidation in the PFC and striatum. Striatal oxidative alterations in GSH and nitrite were observed in females and prevented by NAC. Two-hit induced hippocampal alterations in females, namely expression of GPER-1, α7-nAChR and parvalbumin, were prevented by NAC. CONCLUSION: Our results highlights the influences of sex in NAC preventive effects in rats exposed to a two-hit schizophrenia model.

High Exploratory Phenotype Rats Exposed to Environmental Stressors Present Memory Deficits Accompanied by Immune-Inflammatory/Oxidative Alterations: Relevance to the Relationship Between Temperament and Mood Disorders.

Low-exploratory (LE) and high-exploratory (HE) rodents mimic human depressive and hyperthymic temperaments, respectively. Mood disorders (MD) may be developed by the exposure of these temperaments to environmental stress (ES). Psychiatric symptoms severity in MD patients is related to the magnitude of memory impairment. Thus, we aimed at studying the consequences of the exposure of LE and HE male Wistar rats, during periadolescence, to a combination of ES, namely, paradoxical sleep deprivation (PSD) and unpredictable stress (US), on anxiety-related behavior in the plus maze test, working (WM) and declarative memory (DM) performance. We also evaluated hippocampal immune-inflammatory/oxidative, as consequences of ES, and prevention of ES-induced alterations by the mood-stabilizing drugs, lithium and valproate. Medium exploratory (ME) control rats were used for comparisons with HE- and LE-control rats. We observed that HE-controls presented increased anxiolytic behavior that was significantly increased by ES exposure, whereas LE-controls presented increased anxiety-like behavior relative to ME-controls. Lithium and valproate prevented anxiolytic alterations in HE+ES rats. HE+ES- and LE+ES-rats presented WM and DM deficits. Valproate and lithium prevented WM deficits in LE-PSD+US rats. Lithium prevented DM impairment in HE+ES-rats. Hippocampal levels of reduced glutathione (GSH) increased four-fold in HE+ES-rats, being prevented by valproate and lithium. All groups of LE+ES-rats presented increased levels of GSH in relation to controls. Increments in lipid peroxidation in LE+ES- and HE+ES-rats were prevented by valproate in HE+ES-rats and by both drugs in LE+ES-rats. Nitrite levels were increased in HE+ES- and LE+ES-rats (five-fold increase), which was prevented by both drugs in LE+ES-rats. HE+ES-rats presented a two-fold increase in the inducible nitric oxide synthase (iNOS) expression that was prevented by lithium. HE+ES-rats showed increased hippocampal and plasma levels of interleukin (IL)-1ß and IL-4. Indoleamine 2, 3-dioxygenase 1 (IDO1) was increased in HE+ES- and LE+ES-rats, while tryptophan 2,3-dioxygenase (TDO2) was increased only in HE+ES-rats. Altogether, our results showed that LE- and HE-rats exposed to ES present distinct anxiety-related behavior and similar memory deficits. Furthermore, HE+ES-rats presented more brain and plasma inflammatory alterations that were partially prevented by the mood-stabilizing drugs. These alterations in HE+ES-rats may possibly be related to the development of mood symptoms.

Shared microglial mechanisms underpinning depression and chronic fatigue syndrome and their comorbidities.

In 2011, it was reviewed that a) there is a strong co-occurrence between major depression and chronic fatigue syndrome (CFS), with fatigue and physio-somatic symptoms being key symptoms of depression, and depressive symptoms appearing during the course of CFS; and b) the comorbidity between both disorders may in part be explained by activated immune-inflammatory pathways, including increased translocation of Gram-negative bacteria and increased levels of pro-inflammatory cytokines, such as interleukin (IL)-1. Nevertheless, the possible involvement of activated microglia in this comorbidity has remained unclear. This paper aims to review microglial disturbances in major depression, CFS and their comorbidity. A comprehensive literature search was conducted using the PubMed / MEDLINE database to identify studies, which are relevant to this current review. Depressed patients present neuroinflammatory alterations, probably related to microglial activation, while animal models show that a microglial response to immune challenges including lipopolysaccharides is accompanied by depressive-like behaviors. Recent evidence from preclinical studies indicates that activated microglia have a key role in the onset of fatigue. In chronic inflammatory conditions, such as infections and senescence, microglia orchestrate an inflammatory microenvironment thereby causing fatigue. In conclusion, based on our review we may posit that shared immune-inflammatory pathways and especially activated microglia underpin comorbid depression and CFS. As such, microglial activation and neuro-inflammation may be promising targets to treat the overlapping manifestations of both depression and CFS.

N-3 polyunsaturated fatty acids and clozapine abrogates poly I: C-induced immune alterations in primary hippocampal neurons.

The viral mimetic polyinosinic:polycytidylic acid (poly I:C) is an important tool to study the consequences of viral infection to the development of neuropsychiatric disorders. Here, based on the premise of omega-3 polyunsaturated fatty acids (n3 PUFAs) as supplemental treatment to antipsychotics in schizophrenia, we investigated the involvement of NFkB pathway in the effects of n3 PUFAs or of the atypical antipsychotic clozapine in hippocampal poly I:C-challenged neurons. Primary hippocampal neuronal cultures were exposed to n3 PUFAs (DHA4.35 µM/EPA7.10 µM, DHA 8.7 µM/EPA14.21 µM or DHA17.4 µM/EPA28.42 µM) or clozapine (1.5 or 3 µM) in the presence or absence of poly I:C. MTT assay revealed that poly I:C-induced reduction in cell viability was prevented by n3 PUFAs or clozapine. N3 PUFAs (DHA 8.7 µM/EPA14.21 µM) or clozapine (3 µM) significantly reduced poly I:C-induced increase in iNOS, NFkB (p50/p65), IL-6 and nitrite when compared to non-treated cells. Only n3 PUFAs prevented poly I:C-induced deficits in BDNF. On the other hand, poly I:C caused a marked reduction in DCX immunoexpression, which was prevented only by clozapine. Thus, n3 PUFAs and clozapine exert in vitro neuroprotective effects against poly I:C immune challenge in hippocampal neurons, by mechanisms possibly involving the inhibition of canonical NFkB pathway. The present study adds further evidences to the mechanisms underlying n3 PUFAs and clozapine neuroprotective effects against viral immune challenges. Since n3 PUFAs is a safe strategy for use during pregnancy, our results also add further evidence for the use of this supplement in order to prevent alterations induced by viral hits during this developmental period.

Major depression model induced by repeated and intermittent lipopolysaccharide administration: Long-lasting behavioral, neuroimmune and neuroprogressive alterations.

Major depressed patients show increased bacterial translocation with elevated plasma levels of lipopolysaccharide (LPS), which may trigger immune-inflammatory and neuro-oxidative responses. Recently, an animal model based on chronic LPS administration was developed which was associated with long-lasting depressive-like and neuro-oxidative alterations in female mice. The aim of the current study was to investigate behavioral, neuroimmune and neuroprogressive alterations in female mice 6 weeks after LPS chronic exposure. Female mice received increasing doses of LPS during 5 days at one-month intervals repeated for 4 consecutive months. Six weeks after the last LPS-exposure, we assessed behavioral despair and anhedonia, microglial activation, alterations in tryptophan, 5-HT, kynurenine, quinolinic acid (QUIN) levels and spermidine/spermine N1-acetyltransferase (SAT1) expression in the hippocampus, both with and without fluoxetine administration. Our results show that six weeks post-LPS, mice present behavioral despair and anhedonia in association with increased IBA1 expression (a microglia activation marker), NF-kB p65 and IL-1ß levels, indoleamine 2,3-dioxygenase (IDO1) mRNA expression, kynurenine, QUIN levels and QUIN/tryptophan ratio, and lowered tryptophan, 5-HT levels and SAT1 mRNA expression. Fluoxetine reversed the behavioral and neuroimmune alterations but had no effect in the reversal of IDO1 increased expression, QUIN levels and QUIN/tryptophan ratio. In conclusion, our results support the validity of the chronic LPS model of major depression and additionally shows its translational relevance with respect to neuroimmune and neuroprogressive pathways.