Inflammation in Schizophrenia: Cytokine Levels and Their Relationships to Demographic and Clinical Variables

Rest-activity rhythm disruption and metabolic health in schizophrenia: a cross-sectional actigraphy study of community-dwelling people living with schizophrenia and nonpsychiatric comparison participants

STUDY OBJECTIVES

People living with schizophrenia (PLWS) have increased physical comorbidities and premature mortality which may be linked to dysregulated rest-activity rhythms (RARs). This study aimed to compare RARs between PLWS and nonpsychiatric comparison participants (NCs) and to examine the relationships of RARs with age, sleep, metabolic, and physical health outcomes and, among PLWS, relationships of RARs with illness-related factors.

METHODS

The study sample included 26 PLWS and 36 NCs, assessed with wrist-worn actigraphy to compute RAR variables and general sleep variables. Participants completed assessments for clinical symptoms, physical health, sleep quality, medication use, and assays for fasting glycosylated hemoglobin (hemoglobin A1c) levels. We examined group differences in RAR and sleep variables, relationships of RAR variables with metabolic and physical health measures, and, among PLWS, relationships between RAR variables and illness-related measures.

RESULTS

PLWS had significantly shorter active periods, lower relative amplitude, and lower mean activity during their most active 10 hours compared to the NCs (Cohen's d = 0.79, 0.58, and 0.62, respectively). PLWS had poorer sleep quality, greater mean percent sleep, less wake after sleep onset, and higher total sleep time variability compared to NCs. PLWS had higher rates of antidepressant, anxiolytic, and antipsychotic medication use compared to NCs, which may have impacted sleep quality and objective sleep measures. Across both groups, more fragmented and variable RARs were associated with higher HbA1c levels (ηp2 = .10) and worse physical health (ηp2 = .21). Among PLWS, RARs were correlated with total sleep time (rs = .789, P < .01) and percent sleep (rs = .509, P < .05), but not with age, sleep quality, or other illness-related factors.

CONCLUSIONS

RARs provide unique information about sleep and activity for PLWS and have the potential for targeted interventions to improve metabolic health and mortality.

CITATION

Mahmood Z, Ramsey A, Kidambi N, et al. Rest-activity rhythm disruption and metabolic health in schizophrenia: a cross-sectional actigraphy study of community-dwelling people living with schizophrenia and nonpsychiatric comparison participants. J Clin Sleep Med. 2024;20(9):1505-1516.

The relationship between inflammatory markers, clinical characteristics, and cognitive performance in drug-naïve patients with schizophrenia

Increasing evidence implicates that inflammatory factors do play a crucial role in the pathophysiology of schizophrenia. However, the association between inflammatory markers and different symptom dimensions and cognitive function of schizophrenia remains unclear. A total of 140 drug-naïve patients with schizophrenia and 69 healthy controls matched for age and gender were enrolled. Peripheral blood plasma concentrations of S-100 calcium-binding protein B (S100B), neutrophil gelatinase-associated lipocalin (NGAL), and interferon-γ (IFN-γ) were detected by enzyme-linked immunosorbent assay (ELISA). Psychotic symptoms were measured using the Positive and Negative Syndrome Scale (PANSS), and cognitive function was assessed by the MATRICS Consensus Cognitive Battery (MCCB). Compared with healthy controls, patients with schizophrenia had significantly worse cognitive function and lower levels of NGAL and IFN-γ (P < 0.001). In schizophrenia, plasma NGAL and IFN-γ levels negatively correlated with positive symptom scores (all P < 0.05). There was a positive correlation between plasma levels of NGAL and IFN-γ with visual learning, neurocognition, and MCCB total score (all P < 0.05). We found that NGAL levels (β = 0.352, t = 5.553, 95% CI 0.228-0.477, P < 0.001) and negative symptoms subscale scores (β = - 0.321, OR = 0.725, 95% CI 648-0.811, P < 0.001) were independently associated with the MCCB total score. Further, binary logistic regression analysis indicated that the concentrations of NGAL (β = - 0.246, OR = 0.782, 95% CI 0.651-0.939, P = 0.008) were independently associated with the diagnosis of schizophrenia. There was a positive correlation between NGAL and IFN-γ levels and MCCB total score in schizophrenia. NGAL level was an independent protective factor for cognitive function and an independent risk factor for the diagnosis of schizophrenia.

The relationship between peripheral immune cell markers and cognitive functions in patients with schizophrenia

OBJECTIVES

The purpose of this study was to investigate the relationship between peripheral immune cell markers and cognitive functions in patients with schizophrenia and healthy controls.

METHODS

Thirty-five patients diagnosed with schizophrenia with a stable course and a control group of 35 individuals matched in terms of sex, education, and age were included in this cross-sectional study. The Wisconsin Card Sorting Test (WCST), the Rey Auditory Verbal Learning Test (RAVLT), and the Stroop Test were used for neuropsychological evaluation. Blood neutrophil and lymphocyte percentages, neutrophil-lymphocyte ratio (NLR), and systemic immune-inflammation index (SII) values were calculated.

RESULTS

The female patients exhibited significantly higher NLR and neutrophil percentages than the female controls and higher NLR, neutrophil percentage, and SII than the male patients. The increased neutrophil percentages and NLR and decreased lymphocyte percentages in the female patients were significantly correlated with worsening Stroop interference and RAVLT 1 scores. Additionally, a longer duration of illness was significantly correlated with elevated NLR, SII, and neutrophil percentage and a decreased lymphocyte percentage. A higher number of previous hospitalizations was correlated with elevated SII and decreased lymphocyte percentages. Regression analysis showed a significant association between neutrophil percentages and Stroop interference scores used to evaluate attentional functions in patients with schizophrenia.

CONCLUSIONS

These study results suggest that gender and the course of the illness may affect NLR and SII values. An elevated neutrophil percentage may be one of the factors affecting attentional dysfunction in patients with schizophrenia. Prospective studies are now needed to verify these findings.

Correlation Between Severity of Schizophrenia with Certain Trace Elements and TNF-α Gene Expression and Its Circulatory Level in the Population of Western India

This cross-sectional study aimed to assess serum trace element (TE) concentrations, TNF-α gene expression, protein levels in schizophrenia (SZ) patients, and their correlation with disease severity measured by Positive and Negative Syndrome Scale (PANSS) scores. Forty SZ cases and 40 healthy controls aged 18-60 were recruited. Forty (n = 40) cases who meet ICD-10 criteria for SZ and 40 (n = 40) healthy individuals (controls) between 18 and 60 years of age were recruited in the study. Sandwich enzyme-linked immunosorbent assay (ELISA) and RT-qPCR (quantitative real-time PCR) were used to estimate pro-inflammatory cytokine TNF-α protein and gene expression. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) and graphite furnace atomic absorption spectroscopy (GFAAS) were used to assess serum levels of trace elements (TEs): Fe, Zn, Cu, Mg, and Se. Compared to healthy controls, cases had significantly higher levels of TNF-α protein, as well as Fe, Cu, and Se (p < 0.05). Cu correlated positively with TNF-α protein level (rho = 0.234; p = 0.048) and gene expression (rho = 0.333; p = 0.041) and with PANSS negative (rho = 0.531), general (rho = 0.643), and total (rho = 0.541) scores. Additionally, Zn negatively correlated with serum Mg (rho =  - 0.426, p < 0.01) and positively with serum Se (rho = 0.343, p < 0.05). In conclusion, elevated Cu levels could potentially contribute to the development of SZ. Elevated Cu levels in cases and their correlation with the TNF-α gene and protein and PANSS score indicate Cu's potential role in exacerbating SZ severity through inflammatory cytokines. This suggests the involvement of metals and cytokines in the pathophysiology of SZ.

Correlation of Immune-Inflammatory Response System (IRS)/Compensatory Immune-Regulatory Reflex System (CIRS) with White Matter Integrity in First-Episode Patients with Schizophrenia

Several studies have reported compromised white matter integrity, and that some inflammatory mediators may underlie this functional dysconnectivity in the brain of patients with schizophrenia. The immune-inflammatory response system and compensatory immune-regulatory reflex system (IRS/CIRS) are novel biomarkers for exploring the role of immune imbalance in the pathophysiological mechanism of schizophrenia. This study aimed to explore the little-known area regarding the composite score of peripheral cytokines, the IRS/CIRS, and its correlation with white matter integrity and the specific microstructures most affected in schizophrenia. First-episode patients with schizophrenia (FEPS, n = 94) and age- and sex-matched healthy controls (HCs, n = 50) were enrolled in this study. Plasma cytokine levels were measured using enzyme-linked immunosorbent assay (ELISA), and psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). The whole brain white matter integrity was measured by fractional anisotropy (FA) from diffusion tensor imaging (DTI) using a 3-T Prisma MRI scanner. The IRS/CIRS in FEPS was significantly higher than that in HCs (p = 1.5 × 10-5) and Cohen's d effect size was d = 0.74. FEPS had a significantly lower whole-brain white matter average FA (p = 0.032), which was negatively associated with IRS/CIRS (p = 0.029, adjusting for age, sex, years of education, BMI, and total intracranial volume), but not in the HCs (p > 0.05). Among the white matter microstructures, only the cortico-spinal tract was significantly correlated with IRS/CIRS in FEPS (r =  - 0.543, p = 0.0009). Therefore, elevated IRS/CIRS may affect the white matter in FEPS.

Eight-month intensive meditation-based intervention improves refractory hallucinations and delusions and quality of life in male inpatients with schizophrenia: a randomized controlled trial

AIM

This study investigated the impact of an 8-month daily-guided intensive meditation-based intervention (iMI) on persistent hallucinations/delusions and health-related quality of life (QoL) in male inpatients with schizophrenia with treatment-refractory hallucinations and delusions (TRHDs).

METHODS

A randomized controlled trial assigned 64 male inpatients with schizophrenia and TRHD equally to an 8-month iMI plus general rehabilitation program (GRP) or GRP alone. Assessments were conducted at baseline and the third and eighth months using the Positive and Negative Syndrome Scale (PANSS), 36-Item Short Form-36 (SF-36), and Five Facet Mindfulness Questionnaire (FFMQ). Primary outcomes measured PANSS reduction rates for total score, positive symptoms, and hallucinations/delusions items. Secondary outcomes assessed PANSS, SF-36, and FFMQ scores for psychotic symptoms, health-related QoL, and mindfulness skills, respectively.

RESULTS

In the primary outcome, iMI significantly improved the reduction rates of PANSS total score, positive symptoms, and hallucination/delusion items compared with GRP at both the third and eighth months. Treatment response rates (≥25% reduction) for these measures significantly increased in the iMI group at the eighth month. Concerning secondary outcomes, iMI significantly reduced PANSS total score and hallucination/delusion items, while increasing scores in physical activity and mindfulness skills at both the third and eighth months compared with GRP. These effects were more pronounced with an 8-month intervention compared with a 3-month intervention.

CONCLUSIONS

An iMI benefits patients with TRHDs by reducing persistent hallucinations/delusions and enhancing health-related QoL. Longer iMI duration yields superior treatment outcomes.

Associations of Systemic Inflammation and Senescent Cell Biomarkers with Clinical Outcomes in Older Adults with Schizophrenia

Individuals with schizophrenia suffer from higher morbidity and mortality throughout life partly due to acceleration of aging-related diseases and conditions. Systemic inflammation is a hallmark of aging and is also observed in schizophrenia. An improved understanding of how inflammation and accelerated aging contribute to long-term health outcomes in schizophrenia could provide more effective treatments to preserve long-term cognitive and physical function. In this pilot cross-sectional study, 24 older adults (≥55 years old) with schizophrenia were assessed on symptoms (Positive and Negative Syndrome Scale), neurocognition (Matrics Consensus Cognitive Battery), mobility (Timed Get Up and Go), and general health (SF-12). Serum levels of 112 different cytokines were measured, from which we derived estimated senescence-associated secretory phenotype (SASP) scores for each participant. Two-tailed Pearson's bivariate correlations were computed to test the associations between schizophrenia clinical outcomes with individual cytokines, and SASP. Higher levels of eotaxin, IL-1α, IL-1β, and IFNα are associated with both worse PANSS negative and depressive symptoms scores. IL-1α and IL-1β negatively associated with general physical health whereas eotaxin negatively associated with mobility and global cognition. Overall, we found that specific inflammatory cytokines, but not composite measurements of SASP, are associated with clinical outcomes in older adults with schizophrenia.

Executive functioning trajectories and their prospective association with inflammatory biomarkers in schizophrenia and non-psychiatric comparison participants

BACKGROUND AND HYPOTHESIS

Cognitive change in people with schizophrenia (PwS) is challenging to assess, but important to understand. Previous studies with limited age ranges and follow-up were subject to practice effects. Controlling for practice effects in a well-established cohort, we examined executive functioning trajectories and their association with inflammatory biomarkers, hypothesizing that PwS will have worsening executive functioning over time compared to non-psychiatric comparison participants (NCs), predicted by higher baseline inflammation with a stronger relationship in PwS than NCs.

STUDY DESIGN

Executive functioning was assessed in 350 participants (n = 186 PwS, 164 NCs) at 12-16-month intervals (0 to 7 follow-up visits). Inflammatory biomarkers at baseline included high sensitivity C-Reactive Protein (hs-CRP), Interferon-gamma, Tumor Necrosis Factor (TNF)-alpha, and Interleukin(IL)-6, -8, and - 10. Executive functioning trajectories across diagnostic groups were estimated using a linear mixed-effects model controlling for age, sex, race/ethnicity, and education level, with additional models to assess prediction by baseline inflammation.

STUDY RESULTS

Over 4.4 years average follow-up, improvements in executive functioning were attenuated in PwS and older participants. Controlling for practice effects negated improvements, revealing declines among highly educated participants regardless of diagnosis. Higher baseline hs-CRP predicted worse executive functioning only among NCs, while TNF-alpha was predictive of change in all participants only after controlling for practice effects. Only the main effect of hs-CRP on executive function was significant after adjusting for multiple comparisons. None of the other inflammatory biomarkers predicted executive functioning or trajectories of performance among study participants.

CONCLUSIONS

Systemic inflammation as reflected by baseline inflammatory biomarker levels did not predict longitudinal declines in executive functioning. Additional studies examining the temporal dynamics of inflammation and cognition in PwS will help further clarify their relationship and associated mechanisms.

Neutrophil gelatinase-associated lipocalin (NGAL) and inflammatory markers in schizophrenia: A comparative analysis of drug-naive schizophrenia patients, remitted patients, and healthy controls

This study aims to examine the plasma concentrations of NGAL and other inflammatory parameters, including TNF-α, IL-1β, and IFN-γ, in schizophrenia patients and healthy volunteers. It also investigates potential associations between these biomarkers and symptom severity in schizophrenia and the utility of NGAL as a potential diagnostic and monitoring biomarker for schizophrenia. The study included 49 drug-naive schizophrenia patients (DNS), 59 patients with schizophrenia in remission (REM) on antipsychotic treatment, and 58 healthy volunteers (HC). The Positive and Negative Symptoms Evaluation Scale (PANSS) was utilized to assess the severity of symptoms in schizophrenia patients. Plasma levels of TNF-α, IL-1β, IFN-γ, and NGAL were measured for all participants. NGAL levels were significantly lower in the DNS group than in HC. Significantly lower TNF-α levels were observed in both the DNS and REM groups compared to the HC group. Notably, a statistically significant positive correlation was detected between TNF-α and NGAL levels. The findings of this study are noteworthy, as they demonstrate that drug-naive individuals with schizophrenia exhibit significantly diminished levels of NGAL and TNF-α compared to healthy controls. These identified biomarkers hold promise for providing valuable insights into the complex and evolving pathophysiology of schizophrenia.

Serum HMGB1 and Beclin 1 Levels in Patients with a Diagnosis of Schizophrenia

OBJECTIVE

It is known that inflammation plays a role in the etiopathogenesis of schizophrenia. In this study, we examined high mobility group box 1 protein (HMGB1) and Beclin 1 levels and their relationship with clinical variables in patients with schizophrenia.

METHOD

Forty-three patients with schizophrenia and 43 healthy controls were included in this study. The patients were administered sociodemographic data form, the Positive Negative Symptoms Assessment Scale (PANSS) and the Clinical Global Impressions (CGI) scale. After the scales were filled, venous blood samples were taken from both the patient and control groups to measure serum HMGB1 and Beclin 1 levels. Serum samples obtained at the end of centrifugation were measured by Enzyme-Linked ImmunoSorbent Assay (ELISA) method.

RESULTS

The mean serum HMGB1 levels were significantly increased and the mean serum Beclin 1 levels were significantly decreased in the schizophrenia group compared to the control group. In addition, a negative correlation was found between HMGB1 and Beclin 1 levels.

CONCLUSION

In conclusion, current research shows that HMGB1 is increased and Beclin 1 is decreased in patients with schizophrenia, and these findings may contribute to the role of autophagy in the pathogenesis of schizophrenia.

The association between peripheral inflammation, brain glutamate and antipsychotic response in Schizophrenia: Data from the STRATA collaboration

Glutamate and increased inflammation have been separately implicated in the pathophysiology of schizophrenia and the extent of clinical response to antipsychotic treatment. Despite the mechanistic links between pro-inflammatory and glutamatergic pathways, the relationships between peripheral inflammatory markers and brain glutamate in schizophrenia have not yet been investigated. In this study, we tested the hypothesis that peripheral levels of pro-inflammatory cytokines would be positively associated with brain glutamate levels in schizophrenia. Secondary analyses determined whether this relationship differed according to antipsychotic treatment response. The sample consisted of 79 patients with schizophrenia, of whom 40 were rated as antipsychotic responders and 39 as antipsychotic non-responders. Brain glutamate levels were assessed in the anterior cingulate cortex (ACC) and caudate using proton magnetic resonance spectroscopy (1H-MRS) and blood samples were collected for cytokine assay on the same study visit (IL-6, IL-8, IL-10, TNF- α and IFN-γ). Across the whole patient sample, there was a positive relationship between interferon-gamma (IFN-γ) and caudate glutamate levels (r = 0.31, p = 0.02). In the antipsychotic non-responsive group only, there was a positive relationship between interleukin-8 (IL-8) and caudate glutamate (r = 0.46, p = 0.01). These findings provide evidence to link specific peripheral inflammatory markers and caudate glutamate in schizophrenia and may suggest that this relationship is most marked in patients who show a poor response to antipsychotic treatment.

Self-compassion, but not compassion toward others, is associated with better physical health: A cross-sectional study

Compassion is a modifiable construct that is associated with better physical health outcomes but, to our knowledge, has seldom been studied in people with schizophrenia (PwS) despite its applicability to counteract widespread depression in this community that might prevent positive health behaviors. We hypothesized that, compared to non-psychiatric comparison subjects (NCs), PwS would have lower compassion toward self (CTS), lower compassion toward others (CTO), and a positive association between compassion and health outcomes, such as physical wellbeing, comorbidities, and plasma hs-CRP. This cross-sectional study examined differences in physical health, CTS, and CTO in 189 PwS and 166 NCs. We used general linear models to analyze the relationship between compassion and health. As hypothesized, PwS had lower levels of CTS and CTO, worse physical well-being, more comorbidities, and higher levels of plasma hs-CRP than NCs. In the combined sample, higher CTS was significantly associated with better physical well-being and fewer comorbidities, while higher CTO was significantly associated with more comorbidities. In PwS alone, higher CTS was significantly associated with better physical well-being and lower levels of hs-CRP. CTS seemed to have a larger positive association with physical health than CTO, with depression acting as a potential mediator for CTS. Exploring effects of CTS interventions on physical health and health behaviors could be a promising next step.

An NIMH Workshop on Non-Affective Psychosis in Midlife and Beyond: Research Agenda on Phenomenology, Clinical Trajectories, Underlying Mechanisms, and Intervention Targets

We present a review of the state of the research in the phenomenology, clinical trajectories, biological mechanisms, aging biomarkers, and treatments for middle-aged and older people with schizophrenia (PwS) discussed at the NIMH sponsored workshop "Non-affective Psychosis in Midlife and Beyond." The growing population of PwS has specific clinical needs that require tailored and mechanistically derived interventions. Differentiating between the effects of aging and disease progression is a key challenge of studying older PwS. This review of the workshop highlights the recent findings in this understudied clinical population and the critical gaps in knowledge and consensus for research priorities. This review showcases the major challenges and opportunities for research to advance clinical care for this growing and understudied population.

Depression trajectories and cytokines in schizophrenia spectrum disorders - A longitudinal observational study

Depression occurs frequently in all phases of schizophrenia spectrum disorders. Altered activity in the immune system is seen in both depression and schizophrenia. We aimed to uncover depressive trajectories in a sample of 144 adult individuals with schizophrenia spectrum disorders followed for one year, in order to identify possible cytokine profile differences. Patients were assessed longitudinally with the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale for Schizophrenia (CDSS), where a score above 6 predicts depression. The serum cytokine concentrations for tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-10, IL-12p70 and IL-17A were measured using immunoassays. Latent growth curve models, multilevel models and latent class growth analysis (LCGA) were applied. The LCGA model supported three latent classes (trajectories) with differing CDSS profiles during the one-year follow-up: a high CDSS group (40.8 % of participants), a moderate CDSS group (43.9 %) and a low CDSS group (15.3 %). Five single PANSS items predicted affiliation to depressive trajectory: hallucinations, difficulty in abstract thinking, anxiety, guilt feelings and tension. In the high CDSS group, despite diminishing psychotic symptoms, depressive symptoms persisted throughout one year. The pro-inflammatory cytokines IFN-γ, IL-1β and TNF-α were differentially distributed between the depressive trajectories, although levels remained remarkably stable throughout 12 months. Significant changes were found for the anti-inflammatory cytokine IL-10 at baseline with an accompanying difference in change over time. More research is required to optimize future treatment stratification and investigate the contribution of inflammation in depressed patients with schizophrenia spectrum disorders.

Role of TNF-α -308G/A Polymorphism in Bipolar Disorder and its Relationship with Clinical and Demographic Variables

Objective

Gene-environment interactions might play a significant role in the development of bipolar disorder (BD). The objective of the current study was to investigate the association between tumor necrosis factor (TNF)-α -308 G/A polymorphism and BD and conduct a bioinformatics analysis of the protein-protein network of TNF-α. Gene-environment interactions and the relationship between stressful life events (SLEs) and substance abuse with TNF genotypes and other characteristics were analyzed.

Methods

The genomic deoxyribonucleic acid (DNA) of 400 patients with BD and 200 control subjects were extracted and genotyped for TNF-α -308 G/A polymorphism. SLEs and substance abuse were evaluated using the Life Event and Difficulty Schedule (LEDS) and a self-designed substance abuse questionnaire for the events six months prior to the onset of the disease, respectively. Gene-environment interactions were assessed by multiple statistical tools. Bioinformatics analysis of the TNF-α network and its interacting proteins was carried out using STRING and Cytoscape softwares.

Results

Genotyping analysis revealed a significant association between TNF-α -308 G/A polymorphism and BD (p<0.009). Furthermore, analysis of gene-environment interaction revealed a significant association between TNF-α -308 G/A and SLEs (p=0.001) and TNF-α -308 G/A and substance abuse (p=0.001). Three distinct proteins, RELA, RIPK1, and BIRC3, were identified through hub analysis of the protein network.

Conclusion

TNF-α -308 G/A polymorphism is positively associated with BD. SLEs and substance abuse might trigger the early onset of BD. Proteins identified through bioinformatics analysis might contribute to the TNF-α mediated pathophysiology of BD and can be the potential therapeutic targets.

The Effect of TNF-alpha rs1800629 Polymorphism on White Matter Structures and Memory Function in Patients With Schizophrenia: A Pilot Study

OBJECTIVE

This study investigated the effect of TNF-α rs1800629 polymorphism on white matter integrity and memory function in patients with schizophrenia.

METHODS

Fifty-five participants with schizophrenia were enrolled in this study. They were genotyped for TNF-α rs1800629 polymorphism and underwent diffusion tensor imaging. Memory function was assessed using the Rey-Kim memory test. Participants with schizophrenia were grouped into GG homozygotes and A-allele carriers.

RESULTS

Compared to GG homozygotes, A-allele carriers had significantly lower scores for immediate and delayed recall and recognition of verbal memory and showed significantly lower fractional anisotropy in extensive brain regions. Lower total scores in immediate and delayed recall of verbal memory, immediate recall of visual memory, and figure copy of visual memory were significantly correlated with decreased mean fractional anisotropy in the white matter tracts of the corresponding brain regions.

CONCLUSION

Our findings suggest that the A-allele, which is associated with higher levels of TNF-α expression, correlates with lower connectivity of the fronto-temporal white matter compared to that in GG homozygotes. Impaired fronto-temporal connectivity may be associated with genetic vulnerability to schizophrenia, leading to verbal and visual memory deficits in patients with schizophrenia.

Inflammatory monocyte gene signature predicts beneficial within group effect of simvastatin in patients with schizophrenia spectrum disorders in a secondary analysis of a randomized controlled trial

Immune dysregulation has been reported in schizophrenia spectrum disorders (SSD). In the past decade, several trials using anti-inflammatory agents for treatment of SSD have been completed, with so far limited success. One such anti-inflammatory agent used is simvastatin. A recent, large-scale, randomized controlled trial with simvastatin augmentation failed to show improvement in the predefined primary outcome. However, baseline inflammatory profiles were not taken into account. Here we employed a data-driven clustering approach to investigate whether patients with an inflammatory monocyte gene signature respond better to add-on simvastatin treatment than those without such a signature, over a treatment period of 2 years. In 61 patients (60 randomized, 1:1 placebo:simvastatin) and healthy controls, a previously validated monocyte gene expression signature was assessed using quantitative polymerase chain reaction. Resulting delta cycle threshold values were used to identify patient clusters. Two major patient clusters with either up- or downregulated pro-inflammatory factors were detected. Linear mixed models showed a significant three-way interaction between the inflammatory cluster, treatment, and time for psychotic symptoms. Only patients treated with simvastatin who were in the inflammatory group, showed a consistent improvement: symptom severity gradually decreased after 3 months and reached significance after 12 and 24 months compared to baseline (p.adj<0.05). The effects were small, and overall between-group effects were not significant. Here, we show that patient stratification based on inflammatory gene expression might be useful to select appropriate treatment augmentation for patients with SSD, highlighting the need for precision medicine approaches. Our findings corroborate the results of the primary analyses, showing that in the overall group, simvastatin was not effective; however, at the individual level the treatment might make a difference.

Potential Inflammatory Biomarker in Patients with Attention Deficit Hyperactivity Disorder

Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder that can diminish the quality of life of both children and adults in academic, occupational, and social contexts. The kynurenine pathway (KP) contains a set of enzymatic reactions involved in tryptophan (TRP) degradation. It is known to be associated with the risk of developing ADHD. This review will address the KP and underlying mechanism of inflammation in ADHD. Potential inflammatory biomarkers reported in the most recent studies are summarized. Although a strong neuroimmunological basis has been established due to the advances of recent neurobiological research, the pathophysiology of ADHD remains unclear.

Recommendations of the Schizophrenia Expert Center network for adequate physical activity in real-world schizophrenia (FACE-SZ)

The World Health Organization (WHO) recommends adults complete 150-300 min per week of moderate physical activity or 75-150 min of vigorous physical activity or an equivalent combination of both, to optimize health. To explore the factors associated with adequate MVPA in stabilized outpatients with schizophrenia. 425 stabilized outpatients were recruited in the national FACE-SZ cohort between 2015 and 2018 were evaluated with the International Physical Activity Questionnaire and a 1-day long standardized battery. We explored in multivariate analyses the clinical and pharmacological factors associated with MVPA (model 1) and the biological factors and patient-reported outcomes (model 2). Overall, only 86 (20.2%) of the 425 participants achieved the recommended MVPA threshold. In model 1, the adequate MVPA group was associated with younger age, mood stabilizers prescription and adherence to treatment, independent of sex, positive and depressive symptoms, first-generation antipsychotics prescription, anxiolytic medication, and akathisia. In model 2, adequate MVPA was associated with better glycemic and lipidic profile and better physical and psychological well-being, self-esteem, sentimental life, and resilience independently of age, sex, and current psychotic severity. The expert centers recommend the importance of promoting promote effective MVPA programs for stabilized patients with schizophrenia. Interventions studies suggest that MVPA may be a useful strategy to maximize physical and psychological well-being and self-esteem and potentially to prevent or manage metabolic disturbances.

Peripheral inflammation levels associated with degree of advanced brain aging in schizophrenia

Brain structural abnormalities have been demonstrated in schizophrenia (SZ); these resemble those seen in typical aging, but are seen at younger ages. Furthermore, SZ is associated with accelerated global brain aging, as measured by brain structure-based brain predicted age difference (Brain-PAD). High heterogeneity exists in the degree of brain abnormalities in SZ, and individual differences may be related to levels of peripheral inflammation and may relate to cognitive deficits and negative symptoms. The goal of our study was to investigate the relationship between brain aging, peripheral inflammation, and symptoms of SZ. We hypothesized older brain-PAD in SZ vs. healthy comparison (HC) participants, as well as positive relationships of brain-PAD with peripheral inflammation markers and symptoms in SZ. We analyzed data from two cross-sectional studies in SZ (n = 26; M/F: 21/5) and HC (n = 28; 20/8) (22-64 years). Brain-PAD was calculated using a previously validated Gaussian process regression model applied to raw T1-weighted MRI data. Plasma levels of inflammatory biomarkers (CRP, Eotaxin, Fractalkine, IP10, IL6, IL10, ICAM1, IFNγ, MCP1, MIP1β, SAA, TNFα, VEGF, VCAM1) and cognitive and negative symptoms were assessed. We observed a higher brain-PAD in SZ vs. HC, and advanced brain age relative to chronological age was related to higher peripheral levels of TNFα in the overall group and in the SZ group; other inflammatory markers were not related to brain-PAD. Within the SZ group, we observed no association between cognitive or negative symptoms and brain-PAD. These results support our hypothesis of advanced brain aging in SZ. Furthermore, our findings on the relationship of the pro-inflammatory cytokine TNFα with higher brain-PAD of SZ are relevant to explain heterogeneity of brain ages in SZ, but we did not find strong evidence for cognitive or negative symptom relationships with brain-PAD.

Could CRP be a differential biomarker of illness stages in schizophrenia? A systematic review and meta-analysis

BACKGROUND

Patients with schizophrenia display peripheral inflammation but the impact of illness phase is not clear. Our meta-analysis investigated the difference in CRP levels between patients with schizophrenia and controls according to their illness phase.

METHODS

After a systematic search, all studies measuring CRP in patients with schizophrenia and controls were included. Standardized mean differences were calculated between patients and controls according to illness phase. The influence of sociodemographic and clinical variables on our results was investigated using a meta-regression analysis.

RESULTS

Fifty studies were included in this meta-analysis. Patients with schizophrenia had higher CRP levels than controls in the acute (p < 0.00001) and stable (p < 0.00001) stage of their disease. Patients with acute exacerbation of schizophrenia had higher CRP levels than stable patients (p = 0.02) but this difference did not persist when considering antipsychotic-medicated patients in both phases. Meta-regressions found that the increase of CRP in acutely ill patients as compared to controls was influenced by age (p < 0.01), BMI (p = 0.01) and first episode (p = 0.02), whereas the increase in CRP levels of stable patients as compared to controls was moderated by BMI (p = 0.004).

CONCLUSIONS

In conclusion, this meta-analysis provides strong evidence that patients with schizophrenia have higher CRP levels than controls, but also show an increase in inflammatory response in the acute stage of the disease as compared to the stable stage. CRP could thus be considered as a state marker and a trait marker of the disease.

Schizophrenia Hypothesis: Autonomic Nervous System Dysregulation of Fetal and Adult Immune Tolerance

The autonomic nervous system can control immune cell activation via both sympathetic adrenergic and parasympathetic cholinergic nerve release of norepinephrine and acetylcholine. The hypothesis put forward in this paper suggests that autonomic nervous system dysfunction leads to dysregulation of immune tolerance mechanisms in brain-resident and peripheral immune cells leading to excessive production of pro-inflammatory cytokines such as Tumor Necrosis Factor alpha (TNF-α). Inactivation of Glycogen Synthase Kinase-3β (GSK3β) is a process that takes place in macrophages and microglia when a toll-like receptor 4 (TLR4) ligand binds to the TLR4 receptor. When Damage-Associated Molecular Patterns (DAMPS) and Pathogen-Associated Molecular Patterns (PAMPS) bind to TLR4s, the phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt) pathway should be activated, leading to inactivation of GSK3β. This switches the macrophage from producing pro-inflammatory cytokines to anti-inflammatory cytokines. Acetylcholine activation of the α7 subunit of the nicotinic acetylcholine receptor (α7 nAChR) on the cell surface of immune cells leads to PI3K/Akt pathway activation and can control immune cell polarization. Dysregulation of this pathway due to dysfunction of the prenatal autonomic nervous system could lead to impaired fetal immune tolerance mechanisms and a greater vulnerability to Maternal Immune Activation (MIA) resulting in neurodevelopmental abnormalities. It could also lead to the adult schizophrenia patient’s immune system being more vulnerable to chronic stress-induced DAMP release. If a schizophrenia patient experiences chronic stress, an increased production of pro-inflammatory cytokines such as TNF-α could cause significant damage. TNF-α could increase the permeability of the intestinal and blood brain barrier, resulting in lipopolysaccharide (LPS) and TNF-α translocation to the brain and consequent increases in glutamate release. MIA has been found to reduce Glutamic Acid Decarboxylase mRNA expression, resulting in reduced Gamma-aminobutyric acid (GABA) synthesis, which combined with an increase of glutamate release could result in an imbalance of glutamate and GABA neurotransmitters. Schizophrenia could be a “two-hit” illness comprised of a genetic “hit” of autonomic nervous system dysfunction and an environmental hit of MIA. This combination of factors could lead to neurotransmitter imbalance and the development of psychotic symptoms.

Associations between inflammatory marker profiles and neurocognitive functioning in people with schizophrenia and non-psychiatric comparison subjects

BACKGROUND

Cognitive dysfunction in schizophrenia is the key predictor of functional disability and drives economic burden. Inflammation has been increasingly implicated in the pathogenesis of schizophrenia, yet its role in cognitive decline has not been evaluated. This study explores the association between inflammation and cognitive functioning in persons with schizophrenia.

METHODS

Participants included 143 persons with schizophrenia (PwS) and 139 non-psychiatric comparison subjects (NCs) from an ongoing study of aging. Cognitive assessments included validated measures for executive functioning, processing speed, and visuospatial skills. Plasma levels of nine biomarkers associated with inflammation (high sensitivity C-reactive protein, intercellular adhesion molecule 1, serum amyloid A, interleukin-6, interleukin-8, interferon gamma-induced protein-10, monocyte chemotactic protein-1, fractalkine, and brain-derived neurotrophic factor) were quantified using commercially available, enzyme-linked immunosorbent assays. Partial least squares regression was used to develop a composite "inflammatory profile" to maximize correlations with the cognitive outcomes. We then constructed a best-fit model using these composites and their interactions with diagnosis and sex as the predictors, controlling for covariates.

RESULTS

The biomarker composite, which best correlated with scores on cognitive testing, included high sensitivity C-reactive protein, intercellular adhesion molecule 1, serum amyloid A, interleukin-6, and brain-derived neurotrophic factor, for a 5-biomarker "inflammatory profile." The best-fit model showed a significant biomarker composite by diagnosis by sex three-way interaction, for executive function and processing speed, but not visuospatial skill.

CONCLUSIONS

This approach to building an "inflammatory profile" may provide insight into inflammatory pathways affecting brain function and potential targets for anti-inflammatory interventions to improve cognition in schizophrenia.

Peripheral NF-κB dysregulation in people with schizophrenia drives inflammation: putative anti-inflammatory functions of NF-κB kinases

Elevations in plasma levels of pro-inflammatory cytokines and C-reactive protein (CRP) in patient blood have been associated with impairments in cognitive abilities and more severe psychiatric symptoms in people with schizophrenia. The transcription factor nuclear factor kappa B (NF-κB) regulates the gene expression of pro-inflammatory factors whose protein products trigger CRP release. NF-κB activation pathway mRNAs are increased in the brain in schizophrenia and are strongly related to neuroinflammation. Thus, it is likely that this central immune regulator is also dysregulated in the blood and associated with cytokine and CRP levels. We measured levels of six pro-inflammatory cytokine mRNAs and 18 mRNAs encoding NF-κB pathway members in peripheral blood leukocytes from 87 people with schizophrenia and 83 healthy control subjects. We then assessed the relationships between the alterations in NF-κB pathway genes, pro-inflammatory cytokine and CRP levels, psychiatric symptoms and cognition in people with schizophrenia. IL-1β and IFN-γ mRNAs were increased in patients compared to controls (both p < 0.001), while IL-6, IL-8, IL-18, and TNF-α mRNAs did not differ. Recursive two-step cluster analysis revealed that high levels of IL-1β mRNA and high levels of plasma CRP defined 'high inflammation' individuals in our cohort, and a higher proportion of people with schizophrenia were identified as displaying 'high inflammation' compared to controls using this method (p = 0.03). Overall, leukocyte expression of the NF-κB-activating receptors, TLR4 and TNFR2, and the NF-κB subunit, RelB, was increased in people with schizophrenia compared to healthy control subjects (all p < 0.01), while NF-κB-inducing kinase mRNAs IKKβ and NIK were downregulated in patients (all p < 0.05). We found that elevations in TLR4 and RelB appear more related to inflammatory status than to a diagnosis of schizophrenia, but changes in TNFR2 occur in both the high and low inflammation patients (but were exaggerated in high inflammation patients). Further, decreased leukocyte expression of IKKβ and NIK mRNAs was unique to high inflammation patients, which may represent schizophrenia-specific dysregulation of NF-κB that gives rise to peripheral inflammation in a subset of patients.

Reduced Serum Levels of Soluble Interleukin-15 Receptor α in Schizophrenia and Its Relationship to the Excited Phenotype

Our previous studies documented that interleukin-15 receptor α (IL-15Rα) knockout (KO) mice exhibited hyperactivity, memory impairment, and desperate behavior, which are core features of schizophrenia and depression. Due to the overlapping symptomology and pathogenesis observed for schizophrenia and depression, the present study attempted to determine whether IL-15Rα was associated with the risk of schizophrenia or depression. One hundred fifty-six participants, including 63 schizophrenia patients, 29 depressive patients, and 64 age-matched healthy controls, were enrolled in the study. We investigated the circulating levels of soluble IL-15Rα and analyzed potential links between the IL-15Rα levels and clinical symptoms present in schizophrenia or depressive patients. We observed reduced serum IL-15Rα levels in schizophrenia patients, but not depressive patients compared with controls. Moreover, a significant negative association was observed between the circulating IL-15Rα levels and excited phenotypes in the schizophrenia patients. The IL-15Rα KO mice displayed pronounced pre-pulse inhibition impairment, which was a typical symptom of schizophrenia. Interestingly, the IL-15Rα KO mice exhibited a remarkable elevation in the startle amplitude in the startle reflex test compared to wild type mice. These results demonstrated that serum levels of soluble IL-15Rα were reduced in schizophrenia and highlighted the relationship of IL-15Rα and the excited phenotype in schizophrenia patients and mice.

Multi-omics of human plasma reveals molecular features of dysregulated inflammation and accelerated aging in schizophrenia

Schizophrenia is a devastating psychiatric illness that detrimentally affects a significant portion of the worldwide population. Aging of schizophrenia patients is associated with reduced longevity, but the potential biological factors associated with aging in this population have not yet been investigated in a global manner. To address this gap in knowledge, the present study assesses proteomics and metabolomics profiles in the plasma of subjects afflicted with schizophrenia compared to non-psychiatric control patients over six decades of life. Global, unbiased analyses of circulating blood plasma can provide knowledge of prominently dysregulated molecular pathways and their association with schizophrenia, as well as features of aging and gender in this disease. The resulting data compiled in this study represent a compendium of molecular changes associated with schizophrenia over the human lifetime. Supporting the clinical finding of schizophrenia's association with more rapid aging, both schizophrenia diagnosis and age significantly influenced the plasma proteome in subjects assayed. Schizophrenia was broadly associated with prominent dysregulation of inflammatory and metabolic system components. Proteome changes demonstrated increased abundance of biomarkers for risk of physiologic comorbidities of schizophrenia, especially in younger individuals. These findings advance our understanding of the molecular etiology of schizophrenia and its associated comorbidities throughout the aging process.

The Effectiveness of Chlorpromazine to Decrease the Level of Tumor Necrosis Factor-Alpha Serum in Schizophrenic Patients with Coronavirus Disease 2019

BACKGROUND: The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus-2. The COVID-19 pandemic has also had an impact on mental health, including those with schizophrenia (SCH). There were 131 inpatient schizophrenic patients who were confirmed positive for COVID-19 at Dadi Makassar Hospital, South Sulawesi, Indonesia, but all of these patients did not experience any clinical symptoms of COVID-19. Chlorpromazine as an antipsychotic also has antiviral and anti-inflammatory effects in schizophrenic patients with COVID-19, and the schizophrenic neuroinflammatory is very likely to occur in patients with COVID-19 infection. AIM: The researchers tried to examine the effectiveness of chlorpromazine on serum TNF-values in schizophrenic patients with COVID-19. METHODS: This research is a nested case–control study. The study was conducted on schizophrenic patients with mild and asymptomatic cases of COVID-19 at Dadi Mental Hospital with a sample of 40 patients compared to 42 schizophrenic patients who were not COVID-19. Study subjects received chlorpromazine 100 mg/day for 4 weeks. Serum tumor necrosis factor-alpha (TNF-α) concentrations were measured by enzyme-linked immunosorbent assays when COVID-19 was first confirmed and after 4 weeks. Positive and negative syndrome scale (PANSS) and clinical global impression SCH (CGI-SCH) examinations were also performed to measure the clinical symptoms of SCH. RESULTS: The comparison of baseline TNF-serum levels that increased in the schizophrenic group with COVID-19 was 9.33 pg/ml higher, compared to the schizophrenic group without COVID-19. The decrease in TNF-levels in the schizophrenic group with COVID-19 of 7.96 pg/ml (p < 0.001) indicated an improvement in TNF-serum levels at week 4. Meanwhile, there was no significant decrease in serum TNF- levels in the non-COVID-19 schizophrenic group (p > 0.05). CONCLUSION: The serum TNF-value of schizophrenic patients with COVID-19 is higher than schizophrenic patients without COVID-19. Coadministration of chlorpromazine, antipsychotics, and COVID-19 therapy reduces serum TNF- values in schizophrenic patients with COVID-19. The administration of chlorpromazine and antipsychotic in therapeutic doses reduced the total PANSS and CGI-SCH values.

[A comparative analysis of two methods for assessing the proinflammatory activity of monocytes in patients with juvenile depression]

OBJECTIVE

To show that the results of evaluation of monocyte pro-inflammatory activity (PA) in patients with juvenile depression and healthy donors, obtained using a new method developed by us for counting the relative number of large monocytes on a multifunctional counter and cell analyzer, are similar to the results obtained using a standard assessment of the level of proinflammatory CD14⁺/CD16⁺ - monocytes on a flow cytofluorimeter.

MATERIAL AND METHODS

The PA of monocytes, isolated from the peripheral venous blood of 18 patients with juvenile depression and 12 mentally and somatically healthy age and gender-matched persons was evaluated in two ways: using the generally accepted method of determining the relative number of monocytes with the proinflammatory phenotype CD14⁺/CD16⁺ on a flow cytofluorometer FC-500 and by counting the relative number of large monocytes on a multifunctional counter and cell analyzer Multisizer MS-4. PA of monocytes in patients was studied by using both methods in different variants: in the general group and in the subgroups of patients with low and high levels of active monocytes.

RESULTS

The levels of monocyte PA determined in patients using the two methods did not statistically differ from each other in all variants of the analysis (p=0.6). The equivalence of the obtained results was confirmed by the Chi-square test (r=0.77, p=0.05), as well as by the detection of a statistically significant positive correlation between the number of monocytes with the pro-inflammatory CD14⁺/CD16⁺ phenotype, on the one hand, and the relative number of large monocytes, on the other hand (Spearman r=0.75; p<0.05). At the same time, a comparative analysis of the level of monocyte PA in the general groups of patients and healthy controls revealed significantly higher values of this indicator in patients compared with healthy persons when evaluated by both methods (p<0.05). Definition of monocytes PA using the new method developed by us for counting the relative number of large monocytes on the analyzer and cell counter is more economical and easier to perform, since it does not require the use of expensive devices and reagents, as well as complex device settings and a high level of operator qualification, as in the common method, and is carried out only by two parameters: by counting the number of large monocytes with a diameter of 12.5 to 15 microns and the total number of monocytes with a diameter of 9 to 15 microns.

CONCLUSION

The proposed method for assessing monocyte PA by counting the relative number of large monocytes on the cell counter and analyzer can be used to analyze the activity of monocytes for research purposes.

Relationship between TNF-α levels and psychiatric symptoms in first-episode drug-naïve patients with schizophrenia before and after risperidone treatment and in chronic patients

BACKGROUND

The influence of antipsychotic drugs on tumor necrosis factor-α (TNF-α) levels is unclear, and there is no consensus on the association between TNF-α and psychotic symptoms. This study aimed to investigate the differences in TNF-α levels and clinical correlations in first-episode drug-naïve (FEDN) patients with schizophrenia before and after treatment and in chronic patients.

METHODS

A total of 103 (51 FEDN and 52 chronic) patients and 114 healthy controls were recruited. Demographic and clinical data, including TNF-α levels, were recorded. We used the Positive and Negative Syndrome Scale (PANSS) to measure the psychopathology of all patients.

RESULTS

TNF-α levels before treatment were significantly higher in FEDN patients than in chronic patients and healthy controls. No significant sex differences were found in the TNF-α levels of patients with schizophrenia. The TNF-α levels before treatment were significantly positively related to changes in PANSS negative symptoms in FEDN patients. The TNF-α levels in chronic patients were significantly negatively correlated with the general psychopathology subscales and PANSS total scores.

CONCLUSIONS

Increased TNF-α levels in FEDN patients and their correlation with psychopathology indicate that inflammatory cytokines may play a crucial role in the etiopathogenesis of schizophrenia, and inflammation-directed therapy may, therefore, improve negative symptoms.

Peripheral inflammation is associated with brain SPECT perfusion changes in schizophrenia

PURPOSE

Peripheral inflammation is frequent in schizophrenia and could play a role in the pathophysiology, prognosis, and persistence of psychotic symptomatology under treatment. We seek to determine the relationship between peripheral inflammation and brain SPECT perfusion in stabilized antipsychotic-treated outpatients with schizophrenia, and to determine whether such perfusion changes are correlated with persistent symptoms.

METHODS

Highly sensitive C-reactive protein blood level (hs-CRP) and brain SPECT perfusion were assessed in 137 stabilized outpatients with schizophrenia. Whole-brain voxel-based associations were searched with SPM between SPECT perfusion and hs-CRP (correlation analysis to quantitative levels and between-group analysis according to a threshold of 3 mg/L). The identified clusters were secondarily correlated with clinical symptoms.

RESULTS

After adjustment for age, sex, educational level, illness duration, antidepressant use, chlorpromazine equivalent dose, tobacco smoking and obesity, a negative correlation was found between hs-CRP level and the perfusion of 4 brain areas: the right inferior frontal gyrus, the right middle/superior temporal gyrus, the left superior parietal lobe, and the right postcentral/transverse temporal gyrus (p-voxel < 0.001, k > 80, uncorrected). Increased perfusion of the left amygdala was found in patients with hs-CRP ≥ 3 mg/L compared to those with hs-CRP levels < 3 mg/L. A negative correlation was found between perfusion of the right inferior frontal gyrus and the persistence of positive, negative, and excitement symptoms under antipsychotic treatment.

CONCLUSION

In stabilized patients with schizophrenia, peripheral inflammation is associated with brain perfusion changes that are correlated with the persistence of psychotic symptomatology.

High mobility group box-1 levels in schizophrenia: Potential biomarker of remission phase

Background: Schizophrenia is a chronic mental disorder, characterized byacute exacerbation and remission phases. Immune system has a role in the pathophysiology of schizophrenia. High mobility group box-1 (HMGB-1) is a macrophage secreted protein activating immune cells to produce cytokines. The aim of this study was to evaluate HMGB-1 levels among patients with schizophrenia both in acute exacerbation and remission phases. Methods: Consecutive schizophrenia patients in acute exacerbation and remission phases were enrolled and compared with each other and with age-sex matched healthy subjects. Patients were assessed with the Scale for the Assessment of Positive Symptoms (SAPS), Scale for the Assessment of Negative Symptoms (SANS), Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression Scale (CGI). Results: Mean HMGB-1 levels were not significantly different in acute exacerbation phase versus remission phase schizophrenia patients (2.139±0.564 g/L vs. 2.326± 0.471 g/L, p=0.335) and both were individually higher than the control group (1.791±0.444 g/L, p=0.05 for acute exacerbation vs control, p=0.002 for remission vs control). In remission phase schizophrenic patients, HMGB-1 levels were positively correlated with Scale For The Assessment of Positive Symptoms (r=0.447, p=0.015) and BPRS (r=0.397, p=0.033) scores and HMGB-1 levels were independently associated with BPRS. Conclusions: Serum HMGB-1 levels were shown to be increased in patients with schizophrenia patients irrespective of phase, there were no differences between patients in acute exacerbation and remission phase in terms of biomarker and HMGB-1 levels were related to symptom severity according to psychiatric scales among patients in remission phase of schizophrenia.

Chemokine MCP1 is associated with cognitive flexibility in schizophrenia: A preliminary analysis

BACKGROUND

Peripheral levels of pro-inflammatory biomarkers have been shown to be altered in schizophrenia (SZ) and associated with cognitive impairments, but their relevance to specific cognitive domains remains unclear.

METHODS

Plasma levels of cytokines, chemokines, and vascular biomarkers were quantified and compared between SZ and healthy comparison (HC) groups. Cognition was assessed using the Delis-Kaplan Executive Function System Trail Making (TM) and Color Word Interference (CWI) tests. Linear regression analyses examined differential relationships of inflammatory biomarkers with executive function between groups.

RESULTS

Plasma levels of TNFα, ICAM1, and MCP1 were higher in individuals with SZ compared to HCs. Higher level of MCP1 was associated with increased CWI Inhibition Switching Errors in SZ but not HCs.

CONCLUSION

Like other studies, we found evidence for increased peripheral inflammation in SZ. We also showed that SZ with particularly high MCP1 levels had poor cognitive flexibility. Interventions to reduce chemokine elevations might prove beneficial for cognitive performance.

Roles of inflammation in intrinsic pathophysiology and antipsychotic drug-induced metabolic disturbances of schizophrenia

Schizophrenia is a debilitating psychiatric illness that remains poorly understood. While the bulk of symptomatology has classically been associated with disrupted brain functioning, accumulating evidence demonstrates that schizophrenia is characterized by systemic inflammation and disturbances in metabolism. Indeed, metabolic disease is a major determinant of the high mortality rate associated with schizophrenia. Antipsychotic drugs (APDs) have revolutionized management of psychosis, making it possible to rapidly control psychotic symptoms. This has ultimately reduced relapse rates of psychotic episodes and improved overall quality of life for people with schizophrenia. However, long-term APD use has also been associated with significant metabolic disturbances including weight gain, dysglycemia, and worsening of the underlying cardiometabolic disease intrinsic to schizophrenia. While the mechanisms for these intrinsic and medication-induced metabolic effects remain unclear, inflammation appears to play a key role. Here, we review the evidence for roles of inflammatory mechanisms in the disease features of schizophrenia and how these mechanisms interact with APD treatment. We also discuss the effects of common inflammatory mediators on metabolic disease. Then, we review the evidence of intrinsic and APD-mediated effects on systemic inflammation in schizophrenia. Finally, we speculate about possible treatment strategies. Developing an improved understanding of inflammatory processes in schizophrenia may therefore introduce new, more effective options for treating not only schizophrenia but also primary metabolic disorders.

[Antioxidant status of blood plasma of acutely psychotic patients and its correlation with Nrf2 activation]

OBJECTIVE

To study the correlation between the blood plasma antioxidant profile and the transcriptional activity of the Nrf2 gene in acute psychosis in patients with schizophrenia and alcoholism.

MATERIAL AND METHODS

The study included 40 patients with the first episode of the paranoid form of schizophrenia, 33 patients with schizophrenic psychosis who had previously received therapy, 22 patients with first-time acute alcohol psychosis, and 25 healthy volunteers. The level of Nrf2 in peripheral blood mononuclear cells was estimated by flow cytometry, and the antioxidant profile of blood plasma was estimated with chemiluminometry.

RESULTS

The total and «thiol» antioxidant capacity were reduced in patients with initially diagnosed schizophrenic psychosis and alcoholic psychosis. In patients after treatment, the total antioxidant capacity was higher compared to previously untreated patients. The level of Nrf2 protein in mononuclear cells in patients with the first psychotic episode was significantly lower than in patients with alcoholism and lower than in the control group. In patients with alcoholic psychosis, Nrf2 level was correlated with both the total antioxidant capacity due to uric acid and the «thiol» antioxidant capacity; in patients with psychosis in schizophrenia, Nrf2 level was correlated only with the «thiol» antioxidant capacity.

CONCLUSIONS

The correlation between the total and «thiol» antioxidant capacity and the level of Nrf2 in mononuclear cells of patients with alcohol delirium indicates the undamaged state of the regulation. The absence of a correlation between the total antioxidant capacity and the level of Nrf2 in patients with schizophrenia indicates a disturbance of the activation of the Nrf2 pathway due to, possibly, a part associated with the participation of uric acid.

A comparison of depressive symptom profiles between current major depressive disorder and schizophrenia spectrum disorder

INTRODUCTION

Depressive symptoms are highly prevalent and clinically relevant in schizophrenia spectrum disorder (SSD) patients. So far, little is known about to what extent the depressive symptom profile in SSD is comparable to that seen in major depressive disorder (MDD).

METHODS

Data were derived from the Genetic Risk and Outcome of Psychosis study (GROUP) and the Netherlands Study of Depression and Anxiety (NESDA). We examined differences in severity of depressive symptom profiles and distribution of mood/cognition and somatic/vegetative depressive symptoms using the Quick Inventory of Depressive Symptomatology - Self Report (QIDS-SR) within SSD patients (n = 449), MDD patients (n = 816) and healthy controls (n = 417), aged 18 to 50. Within SSD, associations between depression severity and clinical and demographic data were examined.

RESULTS

60.4% of SSD patients showed substantial depressive symptomatology (QIDS-SR≥6). The difference in mood/cognition symptoms between SSD and MDD was larger (higher symptoms in MDD, effect size = 1.13), than the differences in somatic/vegetative symptoms (effect size 0.74). In patients with SSD, multivariable regression analyses showed that lower social functioning, male gender, use of benzodiazepine and more severe positive symptoms were associated with higher overall depressive symptomatology. The use of antipsychotics or antidepressants was associated with more somatic/vegetative symptoms.

CONCLUSION

More than half of SSD patients have considerable depressive symptomatology, with a relative preponderance of somatic/vegetative symptoms compared to the profile seen in MDD. Future research could explore whether depressive symptom profile in SSD may also be associated with biological dysregulations like in MDD.

The Effects of New Zealand Grown Ginseng Fractions on Cytokine Production from Human Monocytic THP-1 Cells

Pro-inflammatory cytokines and anti-inflammatory cytokines are important mediators that regulate the inflammatory response in inflammation-related diseases. The aim of this study is to evaluate different New Zealand (NZ)-grown ginseng fractions on the productions of pro-inflammatory and anti-inflammatory cytokines in human monocytic THP-1 cells. Four NZ-grown ginseng fractions, including total ginseng extract (TGE), non-ginsenoside fraction extract (NGE), high-polar ginsenoside fraction extract (HPG), and less-polar ginsenoside fraction extract (LPG), were prepared and the ginsenoside compositions of extracts were analyzed by HPLC using 19 ginsenoside reference standards. The THP-1 cells were pre-treated with different concentrations of TGE, NGE, HPG, and LPG, and were then stimulated with lipopolysaccharide (LPS). The levels of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), and anti-inflammatory cytokines, such as interleukin-10 (IL-10), and transforming growth factor beta-1 (TGF-β1), were determined by enzyme-linked immunosorbent assay (ELISA). TGE at 400 µg/mL significantly inhibited LPS-induced TNF-α and IL-6 productions. NGE did not show any effects on inflammatory secretion except inhibited IL-6 production at a high dose. Furthermore, LPG displayed a stronger effect than HPG on inhibiting pro-inflammatory cytokine (TNF-α, IL-1β, and IL-6) productions. Particularly, 100 µg/mL LPG not only significantly inhibited the production of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6, but also remarkably enhanced the production of anti-inflammatory cytokine IL-10. NZ-grown ginseng exhibited anti-inflammatory effects in vitro, which is mainly attributed to ginsenoside fractions (particularly less-polar ginsenosides) rather than non-saponin fractions.

Biological aging in schizophrenia and psychosis severity: DNA methylation analysis

The physiological changes associated with normal aging are known to occur earlier in individuals with schizophrenia (SCZ). One of the phenomena linked with normal aging is the change in patterns of epigenetic modifications. We recruited 138 individuals with SCZ spectrum disorders and extracted DNA from white blood cells. The combinations of pre-selected DNA methylation sites were utilized to estimate the 'methylation age' (DNAm age) and evaluate evidence of epigenetic age acceleration. We investigated the correlation between the epigenetic age acceleration measures and psychosis severity; furthermore, we estimated blood cell counts based on DNA methylation levels. The extrinsic epigenetic age acceleration showed a significant correlation with the Brief Psychiatric Rating Scale (BPRS) disorganization subscale(r=0.222, p=0.039).Both Horvath age acceleration and Hannum age acceleration showed a significant correlation (r=0.221, p=0.029; r=0.242, p=0.017 respectively) with the Symptom Checklist 90 (SCL-90) psychotic domain. Overall, this study shows some evidence of epigenetic age acceleration associated with psychosis severity using two different algorithms for DNAm age analysis.

Gut microbiome in Schizophrenia: Altered functional pathways related to immune modulation and atherosclerotic risk

Emerging evidence has linked the gut microbiome changes to schizophrenia. However, there has been limited research into the functional pathways by which the gut microbiota contributes to the phenotype of persons with chronic schizophrenia. We characterized the composition and functional potential of the gut microbiota in 48 individuals with chronic schizophrenia and 48 matched (sequencing plate, age, sex, BMI, and antibiotic use) non-psychiatric comparison subjects (NCs) using 16S rRNA sequencing. Patients with schizophrenia demonstrated significant beta-diversity differences in microbial composition and predicted genetic functional potential compared to NCs. Alpha-diversity of taxa and functional pathways were not different between groups. Random forests analyses revealed that the microbiome predicts differentiation of patients with schizophrenia from NCs using taxa (75% accuracy) and functional profiles (67% accuracy for KEGG orthologs, 70% for MetaCyc pathways). We utilized a new compositionally-aware method incorporating reference frames to identify differentially abundant microbes and pathways, which revealed that Lachnospiraceae is associated with schizophrenia. Functional pathways related to trimethylamine-N-oxide reductase and Kdo2-lipid A biosynthesis were altered in schizophrenia. These metabolic pathways were associated with inflammatory cytokines and risk for coronary heart disease in schizophrenia. Findings suggest potential mechanisms by which the microbiota may impact the pathophysiology of the disease through modulation of functional pathways related to immune signaling/response and lipid and glucose regulation to be further investigated in future studies.

Immuno-inflammatory changes across phases of early psychosis: The impact of antipsychotic medication and stage of illness

INTRODUCTION

Research examining the role of inflammation in psychosis has produced inconsistent results. Variables that influence inflammation, including antipsychotic medication, are inconsistently controlled across studies and variation of inflammatory analytes across stages of psychosis may also influence findings. The purpose of this study was to assess for evidence of immuno-inflammatory dysregulation across the stages of early psychosis. We examined a immuno-inflammatory analytes in subjects at clinical high risk (CHR) for developing a psychotic disorder, antipsychotic-naïve (-n) and antipsychotic treated (-a) subjects in their first episode of psychosis (FEP), and healthy control (HC) subjects.

METHODS

A total of 11 subjects at CHR, 50 subjects within their FEP (40 FEP-n, 10 FEP-a), and 10 HC subjects were recruited from early psychosis programs in San Diego and Mexico City. Plasma was collected for biomarker assay.

RESULTS

Immuno-inflammatory analytes significantly differed between groups: Interferon-gamma (IFN-γ), Interleukin-10 (IL-10), Eotaxin-1, Interferon Gamma-Induced Protein-10 (IP-10), Monocyte Chemotactic Protein-1 (MCP-1), Macrophage-Derived Chemokine (MDC), Macrophage Inflammatory Protein-1 beta (MIP-1β), Thymus and Activation Regulated Chemokine (TARC), and Brain Derived Neurotropic Factor (BDNF). Post-hoc analyses revealed an overall pattern of higher levels of IL-10, MCP-1, MIP-1β, TARC, and BDNF in CHR as compared to FEP-a, FEP-n, and HC subjects.

CONCLUSIONS

Results reveal a profile of immuno-inflammatory dysregulation in early stages of psychosis prior to psychotic conversion and treatment with antipsychotic medication. The CHR phase of early psychosis may represent a period of increased immuno-inflammatory activation, but due to limited sample size, these results deserve replication in a well characterized early psychosis population.

Association of C-reactive protein and metabolic risk with cognitive effects of lurasidone in patients with schizophrenia

BACKGROUND

Accumulating evidence has implicated insulin resistance and inflammation in the pathophysiology of cognitive impairments associated with neuropsychiatric disorders. This post-hoc analysis based on a placebo-controlled trial investigated the effect of inflammation (indexed by CRP) and metabolic risk factors on cognitive performance in patients with schizophrenia treated with lurasidone.

METHODS

Acutely exacerbated patients with schizophrenia were randomized to lurasidone (80 or 160 mg/day), quetiapine XR 600 mg/day, or placebo. A wide range CRP test and a cognitive assessment using the CogState computerized battery were performed at baseline and week 6 study endpoint. Associations between log-transformed CRP, high density lipoprotein (HDL), homeostatic model assessment of insulin resistance (HOMA-IR) and treatment response were evaluated.

RESULTS

CRP combined with HDL, triglyceride-to-HDL (TG/HDL) ratio, or HOMA-IR at study baseline were significant moderators of the improvement in cognitive performance associated with lurasidone 160 mg/day (vs. placebo) treatment (p < .05). Greater placebo-corrected treatment effect size on the CogState composite score was observed for patients in the lurasidone 160 mg/day treatment group who had either low CRP and high HDL (d = 0.43), or low CRP and low HOMA-IR (d = 0.46). Interactive relationships between CRP, HDL, TG/HDL, HOMA-IR and the antipsychotic efficacy of lurasidone or quetiapine XR were not significant. There were no significant associations between antipsychotic treatment and changes in CRP level at study endpoint.

CONCLUSIONS

Findings of this post-hoc analysis based on a placebo-controlled trial in patients with schizophrenia suggest that baseline CRP level combined with measures of metabolic risk significantly moderated the improvement in cognitive performance associated with lurasidone 160 mg/day (vs. placebo) treatment. Our findings underscore the importance of maintaining a low metabolic risk profile in patients with schizophrenia.

Blood-based kynurenine pathway alterations in schizophrenia spectrum disorders: A meta-analysis

INTRODUCTION

The kynurenine pathway (KP) has been proposed as indirect link between systemic immune responses and clinical symptom development in schizophrenia spectrum disorders (SSD). Empirical evidence for such immune-related KP shifts in SSD has however resulted in divergent findings.

METHODS

We conducted a systematic literature search in PubMed. Thirty papers (total number of patients n = 1506; controls: n = 1432) reported on peripheral concentrations of KP metabolites in SSD patients versus controls. Six KP metabolites were included in a meta-analysis, with secondary analysis of covariate and subgroup effects of patients' symptomatic state, age and duration of illness.

RESULTS

Tryptophan (SMD: -0.30; p = .003) and Xanthurenic Acid (SMD: -0.80; p < .001) were significantly decreased in SSD compared to controls, while Quinolinic Acid (SMD: -0.40; p = .08) and Kynurenic Acid (SMD: -0.39; p = .04) were only significantly decreased in patients with acute or highly symptomatic illness. Finally, in relatively older patient cohorts Kynurenine (SMD: -0.31; p = .02) and Kynurenic Acid (SMD: -0.40; p = .002) were found to be decreased.

CONCLUSION

A partial downregulation of the KP is observed in SSD patients, in particular during acute symptomatic states and in older age, effects that were independent from each other. In contrast, younger and stable or remitted patients display limited to no KP metabolite abnormalities. The current meta-analysis illustrates the dynamic nature of KP abnormalities. It should be noted that all included studies investigated peripheral KP metabolites, which do not necessarily reflect central KP metabolite abnormalities in schizophrenic patients.

Genes regulated by BCL11B during T-cell development are enriched for de novo mutations found in schizophrenia patients

While abnormal neurodevelopment contributes to schizophrenia (SCZ) risk, there is also evidence to support a role for immune dysfunction in SCZ. BCL11B, associated with SCZ in genome-wide association study (GWAS), is a transcription factor that regulates the differentiation and development of cells in the central nervous and immune systems. Here, we use functional genomics data from studies of BCL11B to investigate the contribution of neuronal and immune processes to SCZ pathophysiology. We identified the gene targets of BCL11B in brain striatal cells (n = 223 genes), double negative 4 (DN4) developing T cells (n = 114 genes) and double positive (DP) developing T cells (n = 518 genes) using an integrated analysis of RNA-seq and ChIP-seq data. No gene-set was enriched for genes containing common variants associated with SCZ but the DP gene-set was enriched for genes containing missense de novo mutations (DNMs; p = .001) using data from 3,447 SCZ trios. Post hoc analysis revealed the enrichment to be stronger for DP genes negatively regulated by BCL11B. Biological processes enriched for genes negatively regulated by BCL11B in DP gene-set included immune system development and cytokine signaling. These analyses, leveraging a GWAS-identified SCZ risk gene and data on gene expression and transcription factor binding, indicate that DNMs in immune pathways contribute to SCZ risk.

Altered structural connectivity and cytokine levels in Schizophrenia and Genetic high-risk individuals: Associations with disease states and vulnerability

BACKGROUND

Alterations of white matter (WM) integrity have been observed in both schizophrenia (SZ) and individuals at genetic high risk for SZ (GHR-SZ); however, the molecular mechanisms underlying WM disruption remain unclear. Cytokines are chemical messengers of the immune system that are closely related to inflammation and neurogenesis in the brain. This study aimed to identify abnormalities in WM integrity, cytokine levels, and their association in SZ and GHR-SZ.

METHODS

A total of 355 participants (126 with SZ, 99 GHR-SZ, and 130 healthy controls [HCs]) were recruited. All participants underwent diffusion tensor imaging and blood samples were obtained from 113 participants within 24 h of imaging.

RESULTS

In SZ, there was decreased fractional anisotropy(FA) in the genu and body of the corpus callosum (GCC/BCC), anterior corona radiata, anterior and posterior limbs of the internal capsule (ALIC/PLIC), superior fronto-occipital fasciculus, external capsule, and fornix, and elevated IL-6 levels. In both SZ and GHR-SZ, decreased FA in the splenium of the corpus callosum (SCC), posterior corona radiate (PCR), and posterior thalamic radiation (PTR) was observed, and elevated leptin levels were present. Additionally, the IL-6 levels were negatively correlated with FA in the GCC and ALIC in SZ, and leptin levels were negatively correlated with the SCC, PCR, and PTR in SZ and GHR-SZ.

CONCLUSIONS

Abnormal WM integrity in SZ may reflect the state of disease and is associated with increased IL-6 levels. In addition, these leptin-associated WM integrity abnormalities in both SZ and GHR-SZ may reflect a genetic vulnerability to SZ.

Immune Factor, TNFα, Disrupts Human Brain Organoid Development Similar to Schizophrenia-Schizophrenia Increases Developmental Vulnerability to TNFα

Schizophrenia (SZ) is a neurodevelopmental genetic disorder in which maternal immune activation (MIA) and increased tumor necrosis factor-α (TNF-α) may contribute. Previous studies using iPSC-derived cerebral organoids and neuronal cells demonstrated developmental malformation and transcriptional dysregulations, including TNF receptors and their signaling genes, common to SZ patients with diverse genetic backgrounds. In the present study, we examined the significance of the common TNF receptor dysregulations by transiently exposing cerebral organoids from embryonic stem cells (ESC) and from representative control and SZ patient iPSCs to TNF. In control iPSC organoids, TNF produced malformations qualitatively similar in, but generally less pronounced than, the malformations of the SZ iPSC-derived organoids. TNF and SZ alone disrupted subcortical rosettes and dispersed proliferating Ki67⁺ neural progenitor cells (NPC) from the organoid ventricular zone (VZ) into the cortical zone (CZ). In the CZ, the absence of large ramified pan-Neu⁺ neurons coincided with loss of myelinated neurites despite increased cortical accumulation of O4⁺ oligodendrocytes. The number of calretinin⁺ interneurons increased; however, they lacked the preferential parallel orientation to the organoid surface. SZ and SZ+TNF affected fine cortical and subcortical organoid structure by replacing cells with extracellular matrix (ECM)-like fibers The SZ condition increased developmental vulnerability to TNF, leading to more pronounced changes in NPC, pan-Neu⁺ neurons, and interneurons. Both SZ- and TNF-induced malformations were associated with the loss of nuclear (n)FGFR1 form in the CZ and its upregulation in deep IZ regions, while in earlier studies blocking nFGFR1 reproduced cortical malformations observed in SZ. Computational analysis of ChiPseq and RNAseq datasets shows that nFGFR1 directly targets neurogenic, oligodendrogenic, cell migration, and ECM genes, and that the FGFR1-targeted TNF receptor and signaling genes are overexpressed in SZ NPC. Through these changes, the developing brain with the inherited SZ genome dysregulation may suffer increased vulnerability to TNF and thus, MIA.

The Role of Cytokines in Predicting the Efficacy of Acute Stage Treatment in Patients with Schizophrenia

PURPOSE

Inflammatory response in schizophrenia (SCz) is related to its underlying pathological mechanism and might be significant in deciding a patient's prognosis. The current study aims to investigate the differences in the serum inflammation level between schizophrenic patients and healthy controls and identify inflammatory markers that can predict clinical therapeutic effects in early-stage SCz patients at the 6-month follow-up.

PATIENTS AND METHODS

In total, 71 subjects were recruited in this study, including 35 patients with Scz and 36 healthy controls. The 35 Scz patients, who were in the first-episode or acute relapse state at admission, had completed the 6-month follow-up. The Positive and Negative Syndrome Scale (PANSS) and the Clinical Global Impression (CGI) assessment results, demographic details, and blood samples were collected at the baseline and at follow-up. Data were analyzed using the Spearman correlation and multiple linear regression.

RESULTS

Serum interleukin (IL-1β, IL-4, IL-6, and IL-8) levels were significantly elevated in SCz patients at baseline compared with healthy controls, with a reduced IL-8 level at the follow-up. Furthermore, a higher IL-6 level and lower IL-8 level was found to predict better improvement in negative symptoms. The higher IL-6 level also predicted lesser improvement in depressive symptoms. Finally, a higher interferon (IFN)-γ level predicted a lower therapeutic effect for excitatory symptoms.

CONCLUSION

The serum levels of inflammatory markers were higher in patients with SCz than in healthy controls. These markers can be considered accurate predictors of therapeutic effects in patients with SCz.

The Neuroimmune and Neurotoxic Fingerprint of Major Neurocognitive Psychosis or Deficit Schizophrenia: a Supervised Machine Learning Study

No studies have examined the immune fingerprint of major neurocognitive psychosis (MNP) or deficit schizophrenia using M1 macrophage cytokines in combination with chemokines such as CCL2 and CCL11. The present study delineated the neuroimmune fingerprint of MNP by analyzing plasma levels of IL-1β, sIL-1RA, TNFα, sTNFR1, sTNFR2, CCL2, and CCL11 in 120 MNP versus 54 healthy controls in association with neurocognitive scores (as assessed with the Brief Assessment of Cognition in Schizophrenia) and PHEMN (psychotic, hostility, excitation, mannerism and negative) symptoms. MNP was best predicted by a combination of CCL11, TNFα, IL-1β, and sIL-1RA which yielded a bootstrapped (n = 2000) area under the receiver operating curve of 0.985. Composite scores reflecting M1 macrophage activity and neurotoxic potential including effects of CCL11 and CCL2 were significantly increased in MNP. A large part of the variance in PHEM (38.4-52.6%) and negative (65.8-74.4%) symptoms were explained by combinations of immune markers whereby CCL11 was the most important. The same markers explained a large part of the variance in the Mini-Mental State examination, list learning, digit sequencing task, category instances, controlled word association, symbol coding, and Tower of London. Partial least squares analysis showed that 72.7% of the variance in overall severity of schizophrenia was explained by the regression on IL-1β, sIL-1RA, CCL11, TNFα, and education. It is concluded that the combination of the abovementioned markers defines MNP as a distinct neuroimmune disorder and that increased immune neurotoxicity determines memory and executive impairments and PHEMN symptoms as well.

The aetiology of social deficits within mental health disorders: The role of the immune system and endogenous opioids

The American National Institute for Mental Health (NIMH) has put out a set of research goals that include a long-term plan to identify more reliable endogenous explanations for a wide variety of mental health disorders (Insel, 2013). In response to this, we have identified a major symptom that underlies multiple mental health disorders - social bonding dysfunction. We suggest that endogenous opioid abnormalities can lead to altered social bonding, which is a symptom of various mental health disorders, including depression, schizophrenia and ASD. This article first outlines how endogenous opioids play a role in social bonding. Then we show their association with the body's inflammation immune function, and review recent literature linking inflammation to mental health 'immunophenotypes'. We finish by explaining how these immunophenotypes may be caused by alterations in the endogenous opioid system. This is the first overview of the role of inflammation across multiple disorders where we provide a biochemical explanation for why immunophenotypes might exist across diagnoses. We propose a novel mechanism of how the immune system may be causing 'sickness-type' behaviours (fatigue, appetite change, social withdrawal and inhibited motivation) in those who have these immunophenotypes. We hope that this novel aetiology can be used as a basis for future research in mental health.

High prevalence and adverse health effects of loneliness in community-dwelling adults across the lifespan: role of wisdom as a protective factor

OBJECTIVES

This study of loneliness across adult lifespan examined its associations with sociodemographics, mental health (positive and negative psychological states and traits), subjective cognitive complaints, and physical functioning.

DESIGN

Analysis of cross-sectional data.

PARTICIPANTS

340 community-dwelling adults in San Diego, California, mean age 62 (SD = 18) years, range 27-101 years, who participated in three community-based studies.

MEASUREMENTS

Loneliness measures included UCLA Loneliness Scale Version 3 (UCLA-3), 4-item Patient-Reported Outcomes Measurement Information System (PROMIS) Social Isolation Scale, and a single-item measure from the Center for Epidemiologic Studies Depression (CESD) scale. Other measures included the San Diego Wisdom Scale (SD-WISE) and Medical Outcomes Survey- Short form 36.

RESULTS

Seventy-six percent of subjects had moderate-high levels of loneliness on UCLA-3, using standardized cut-points. Loneliness was correlated with worse mental health and inversely with positive psychological states/traits. Even moderate severity of loneliness was associated with worse mental and physical functioning. Loneliness severity and age had a complex relationship, with increased loneliness in the late-20s, mid-50s, and late-80s. There were no sex differences in loneliness prevalence, severity, and age relationships. The best-fit multiple regression model accounted for 45% of the variance in UCLA-3 scores, and three factors emerged with small-medium effect sizes: wisdom, living alone and mental well-being.

CONCLUSIONS

The alarmingly high prevalence of loneliness and its association with worse health-related measures underscore major challenges for society. The non-linear age-loneliness severity relationship deserves further study. The strong negative association of wisdom with loneliness highlights the potentially critical role of wisdom as a target for psychosocial/behavioral interventions to reduce loneliness. Building a wiser society may help us develop a more connected, less lonely, and happier society.

A novel biomarker of cardiometabolic pathology in schizophrenia?

BACKGROUND

Persons with schizophrenia and schizoaffective disorder (PwS) have high rates of cardiometabolic pathology that contributes to premature mortality. Adiponectin is a metabolic hormone affecting insulin sensitivity and inflammation, and is active in the brain. High-molecular weight (HMW) adiponectin is considered a more sensitive marker of metabolic dysfunction than total adiponectin, but has been poorly studied in schizophrenia.

METHODS

This was a cross-sectional study of 100 PwS, age range 26-68 years (46 women), and 93 age- and sex-comparable non-psychiatric comparison (NC) subjects. Assessments included measures of psychopathology, physical health, cognitive function, and circulating biomarkers of metabolic dysfunction (HMW adiponectin, lipids, insulin resistance) and inflammation (high-sensitivity C-reactive protein or hs-CRP, Tumor Necrosis Factor-α, Interleukin-6, and Interleukin-10).

RESULTS

HMW adiponectin levels were lower in PwS compared to NCs. Lower HMW adiponectin levels were associated with higher body mass index (BMI), higher Framingham risk for coronary heart disease, higher number of metabolic syndrome criteria, greater insulin resistance, lower HDL cholesterol, and higher hs-CRP in both groups. Only in PwS, lower HMW adiponectin correlated with younger age. In the best-fit regression models of HMW adiponectin, lower levels were associated with lower HDL cholesterol and minority race/ethnicity in both groups; but with younger age, non-smoking, higher insulin resistance, and a diagnosis of schizoaffective disorder only among PwS, and with male sex, better cognitive functioning, and higher hs-CRP levels in NCs only.

DISCUSSION

HMW adiponectin may be a promising biomarker of cardiometabolic health, especially among PwS. Adiponectin is a potential target for lifestyle and pharmacological interventions. Research on the possible role of HMW adiponectin in modifying cardiometabolic pathology in schizophrenia is needed.

Targeting Interleukin-6 Signaling in Clinic

Interleukin-6 (IL-6) is a pleiotropic cytokine with roles in immunity, tissue regeneration, and metabolism. Rapid production of IL-6 contributes to host defense during infection and tissue injury, but excessive synthesis of IL-6 and dysregulation of IL-6 receptor signaling is involved in disease pathology. Therapeutic agents targeting the IL-6 axis are effective in rheumatoid arthritis, and applications are being extended to other settings of acute and chronic inflammation. Recent studies reveal that selective blockade of different modes of IL-6 receptor signaling has different outcomes on disease pathology, suggesting novel strategies for therapeutic intervention. However, some inflammatory diseases do not seem to respond to IL-6 blockade. Here, we review the current state of IL-6-targeting approaches in the clinic and discuss how to apply the growing understanding of the immunobiology of IL-6 to clinical decisions.