C-reactive protein is associated with the severity of cognitive impairment but not of psychiatric symptoms in individuals with schizophrenia

Inflammatory markers are associated with general cognitive abilities in schizophrenia and bipolar disorder patients and healthy controls

BACKGROUND

The mechanisms underlying cognitive impairment in schizophrenia and bipolar disorders are largely unknown. Immune abnormalities have been found in both disorders, and inflammatory mediators may play roles in cognitive function. We investigated if inflammatory markers are associated with general cognitive abilities.

METHODS

Participants with schizophrenia spectrum (N=121) and bipolar spectrum (N=111) disorders and healthy controls (N=241) were included. General intellectual abilities were assessed using the Wechsler Abbreviated Scale of Intelligence (WASI). Serum concentrations of the following immune markers were measured: Soluble tumor necrosis factor receptor 1 (sTNF-R1), interleukin 1 receptor antagonist (IL-1Ra), osteoprotegerin, von Willebrand factor, C-reactive protein, interleukin-6 and CD40 ligand.

RESULTS

After adjusting for age, sex and diagnostic group, significant negative associations with general cognitive function were found for sTNF-R1 (p=2×10(-5)), IL-1Ra (p=0.002) and sCD40 ligand (p=0.003). Among patients, the associations remained significant (p=0.006, p=0.005 and p=0.02) after adjusting for possible confounders including education, smoking, psychotic and affective symptoms, body mass index, cortisol, medication and time of blood sampling. Subgroup analysis, showed that general cognitive abilities were significantly associated with IL-1Ra and sTNF-R1 in schizophrenia patients, with sCD40L and IL-1Ra in bipolar disorder patients and with sTNF-R1 in healthy controls.

CONCLUSION

The study shows significant negative associations between inflammatory markers and general cognitive abilities after adjusting for possible confounders. The findings strongly support a role for inflammation in the neurophysiology of cognitive impairment.

Association between ANKK1 (rs1800497) and LTA (rs909253) Genetic Variants and Risk of Schizophrenia

Limited research has assessed associations between schizophrenia and genetic variants of the ankyrin repeat and kinase domain containing 1 (ANKK1) and lymphotoxin-alpha (LTA) genes among individuals of Middle Eastern ancestry. Here we present the first association study investigating the ANKK1 rs1800497 (T>C) and LTA rs909253 (A>G) single-nucleotide polymorphisms in an Egyptian population. Among 120 patients with DSM-IV and PANSS (Positive and Negative Syndrome Scale) assessments of schizophrenia and 100 healthy controls, we determined the genotypes for the polymorphisms using endonuclease digestion of amplified genomic DNA. Results confirmed previous findings from different ethnic populations, in that the rs1800497 and rs909253 polymorphisms were both associated with risk of schizophrenia. Differences between the genotypes of cases and controls were strongly significant (P = 0.0005 for rs1800497 and P = 0.001 for rs909253). The relative risk to schizophrenia was 1.2 (P = 0.01) for the C allele and 0.8 (P = 0.04) for the G allele. The CC, GG, and combined CC/AA genotypes were all more frequent in cases than in controls. These results support an association between ANKK1 and LTA genetic markers and vulnerability to schizophrenia and show the potential influence of just one copy of the mutant C or G allele in the Egyptian population.

Quality of life is associated with chronic inflammation in schizophrenia: a cross-sectional study

Inflammation may play a crucial role in the pathogenesis of schizophrenia. However, the association between chronic inflammation and health outcomes in schizophrenia remains unclear, particularly for patient-reported outcomes. The aim of this study was to investigate the relationship between quality of life (QoL) and chronic inflammation assessed using C -Reactive Protein (CRP) in patients with schizophrenia. Two hundred and fifty six patients with schizophrenia were enrolled in this study. After adjusting for key socio-demographic and clinical confounding factors, patients with high levels of CRP (>3.0 mg/l) had a lower QoL than patients with normal CRP levels (OR = 0.97, 95% CI = 0.94–0.99). An investigation of the dimensions of QoL revealed that psychological well-being, physical well-being and sentimental life were the most salient features of QoL associated with CRP. Significant associations were found between lower educational level (OR = 4.15, 95% CI = 1.55–11.07), higher body mass index (OR = 1.16, 95% CI = 1.06–1.28), higher Fagerström score (OR = 1.22, 95% CI = 1.01–1.47) and high levels of CRP. After replications with longitudinal approaches, the association between QoL and chronic inflammation may offer interesting interventional prospects to act both on inflammation and QoL in patients with schizophrenia.

Elevated C-reactive protein is associated with sensory gating deficit in schizophrenia

Sensory and cognitive impairments and inflammatory processes are contributing factors to the pathogenesis of schizophrenia. A previous study found that an elevated CRP level (≥5mg/L) was associated with higher cognitive impairments in schizophrenia. We aimed to investigate the association between an elevated CRP level and sensory impairments defined by a sensory gating deficit (abnormal P50 suppression) in 55 outpatients. Fifteen patients (27.3%) had an elevated CRP level that was associated with higher rate of sensory gating deficit (60% vs. 12.5%, p<0.001). This is the first study suggesting a relationship between sensory gating deficit and inflammatory processes in schizophrenia.

Soluble urokinase-type plasminogen activator receptor levels in patients with schizophrenia

BACKGROUND

The etiology of schizophrenia remains largely unknown but alterations in the immune system may be involved. In addition to the psychiatric symptoms, schizophrenia is also associated with up to 20 years reduction in life span. Soluble urokinase-type plasminogen activator receptor (suPAR) is a protein that can be measured in blood samples and reflects the levels of inflammatory activity. It has been associated with mortality and the development of type 2 diabetes and cardiovascular disease.

METHODS

suPAR levels in patients with schizophrenia were compared to healthy controls from the Danish Blood Donor Study. SuPAR levels were dichotomized at >4.0 ng/ml, which is considered the threshold for low grade inflammation. A multiple logistic regression model was used and adjusted for age, sex, and current smoking.

RESULTS

In total we included 1009 subjects, 105 cases with schizophrenia (10.4%) and 904 controls (89.6%). The mean suPAR values were 4.01 ng/ml (SD = 1.43) for the cases vs 1.91 ng/ml (SD = 1.35) for the controls (P < .001). Multiple logistic regression with odds ratio (OR) for suPAR levels >4.0 ng/ml yielded: schizophrenia, OR: 46.15 95% CI 22.69-93.87, P < .001; age, OR: 1.02 95% CI 0.99-1.02, P = .15; male sex, OR: 0.70 95% CI 0.35-1.36, P = .29; and current smoking, OR: 3.51 95% CI 1.78-6.94, P < .001.

CONCLUSIONS

Patients with schizophrenia had significantly higher suPAR levels than healthy controls. Further studies are warranted to clarify if elevated suPAR levels are involved in the pathophysiology of schizophrenia and/or the increased mortality found in patients with schizophrenia.

Association between altered brain morphology and elevated peripheral endothelial markers--implications for psychotic disorders

BACKGROUND

Increased inflammation, endothelial dysfunction, and structural brain abnormalities have been reported in both schizophrenia and bipolar disorder, but the relationships between these factors are unknown. We aimed to identify associations between markers of inflammatory and endothelial activation and structural brain variation in psychotic disorders.

METHODS

We measured von Willebrand factor (vWf) as a marker of endothelial cell activation and six inflammatory markers (tumor necrosis factor-receptor 1, osteoprotegerin, interleukin-1-receptor antagonist, interleukin-6, C-reactive protein, CD40 ligand) in plasma and 16 brain structures obtained from MRI scans of 356 individuals (schizophrenia spectrum; n=121, affective spectrum; n=95, healthy control subjects; n=140). The relationship between the inflammatory and endothelial markers and brain measurements were investigated across groups.

RESULTS

There was a positive association (p=2.5×10(-4)) between plasma levels of vWf and total volume of the basal ganglia which remained significant after correction for multiple testing. Treatment with first generation antipsychotics was associated with basal ganglia volume only (p=0.009). After adjusting for diagnosis and antipsychotic medication, vWf remained significantly associated with increased basal ganglia volume (p=0.008), in particular the right globus pallidus (p=3.7×10(-4)). The relationship between vWf and basal ganglia volume was linear in all groups, but the intercept was significantly higher in the schizophrenia group (df=2, F=8.2, p=3.4×10(-4)).

CONCLUSION

Our results show a strong positive correlation between vWf levels and basal ganglia volume, in particular globus pallidus, independent of diagnosis. vWf levels were significantly higher in schizophrenia, which could indicate a link between endothelial cell activation and basal ganglia morphology in schizophrenia patients.

The neurobiology and treatment of first-episode schizophrenia

It is evident that once psychosis is present in patients with schizophrenia, the underlying biological process of the illness has already been ongoing for many years. At the time of diagnosis, patients with schizophrenia show decreased mean intracranial volume (ICV) as compared with healthy subjects. Since ICV is driven by brain growth, which reaches its maximum size at approximately 13 years of age, this finding suggests that brain development in patients with schizophrenia is stunted before that age. The smaller brain volume is expressed as decrements in both grey and white matter. After diagnosis, it is mainly the grey matter loss that progresses over time whereas white matter deficits are stable or may even improve over the course of the illness. To understand the possible causes of the brain changes in the first phase of schizophrenia, evidence from treatment studies, postmortem and neuroimaging investigations together with animal experiments needs to be incorporated. These data suggest that the pathophysiology of schizophrenia is multifactorial. Increased striatal dopamine synthesis is already evident before the time of diagnosis, starting during the at-risk mental state, and increases during the onset of frank psychosis. Cognitive impairment and negative symptoms may, in turn, result from other abnormalities, such as NMDA receptor hypofunction and low-grade inflammation of the brain. The latter two dysfunctions probably antedate increased dopamine synthesis by many years, reflecting the much earlier presence of cognitive and social dysfunction. Although correction of the hyperdopaminergic state with antipsychotic agents is generally effective in patients with a first-episode psychosis, the effects of treatments to correct NMDA receptor hypofunction or low-grade inflammation are (so far) rather modest at best. Improved efficacy of these interventions can be expected when they are applied at the onset of cognitive and social dysfunction, rather than at the onset of psychosis.

Interleukin-6: the missing element of the neurocognitive deterioration in schizophrenia? The focus on genetic underpinnings, cognitive impairment and clinical manifestation

The influence of the immune system deregulation on the risk of schizophrenia is increasingly recognized. The aim of this study was to assess the influence of serum interleukin-6 (IL-6) level together with the polymorphism in its gene (IL6 -174G/C) and high sensitivity C-reactive protein (hsCRP) levels on clinical manifestation and cognition in schizophrenia patients. We recruited 151 patients with schizophrenia and 194 healthy control subjects. Psychopathology was evaluated using Operational Criteria for Psychotic Illness checklist, Positive and Negative Syndrome Scale (PANSS) and Scales for Assessment of Positive and Negative Symptoms. Cognitive performance in schizophrenia patients was assessed using following tests: Rey Auditory Verbal Learning Test, Trail Making Test, Verbal Fluency Tests, Stroop and subscales from Wechsler Adults Intelligence Scale-R-Pl (Similarities, Digit Symbol Coding, Digit Span Forward and Backward). Serum IL-6 and hsCRP levels were significantly higher in schizophrenia patients in comparison with healthy controls. Both hsCRP and IL-6 levels were associated with insidious psychosis onset, duration of illness and chronic schizophrenia course with deterioration. After adjustment for age, education level, number of years of completed education, illness duration, total PANSS score, depression severity and chlorpromazine equivalent, there was still a positive association between IL-6 and hsCRP levels and worse cognitive performance. The IL6 -174G/C polymorphism did not influence IL-6 level, but it was associated with the severity of positive symptoms. Our results suggest that elevated IL-6 levels may play the role in cognitive impairment and serve as potential inflammatory biomarker of deterioration in schizophrenia.

Differential susceptibility of white matter tracts to inflammatory mediators in schizophrenia: an integrated DTI study

BACKGROUND

The pathophysiological underpinnings of impaired anatomical and functional connectivity are not precisely known. Emerging data suggest that immune mediators may underlie such dysconnectivity. We examined anatomical brain connections using diffusion tensor imaging (DTI) data in relation to interleukin-6 (IL-6) and C-reactive protein (CRP) levels among early-course clinically stable schizophrenia subjects compared to healthy controls (HC).

METHODS

DTI data were acquired in 30 directions with 2 averages. Fractional anisotropy (FA) and radial diffusivity (RD) maps were separately processed using FSL4.1.9 and Tract-Based Spatial Statistics (TBSS). Threshold free cluster enhancements (TFCE) were examined employing familywise error (FWE) corrections for multiple testing within linear regression models including age, sex and socioeconomic status as covariates. IL-6 and CRP were assayed using highly sensitive and specific sandwich immunosorbent assays.

RESULTS

The groups did not differ in age and sex as well as in the IL-6 and CRP levels. IL-6 levels were negatively correlated with the FA and positively correlated with RD among schizophrenia subjects but not HC. The voxel clusters that showed significant correlations were localized to the forceps major, the inferior longitudinal fasciculus and the inferior fronto-occipital fasciculus. CRP levels showed similar pattern except for lack of correlation with RD on any cluster that corresponded to the forceps major.

DISCUSSION

Our results suggest that the IL-6 and CRP contribute to impaired anisotropy of water diffusion in selected pathways that have been previously associated with schizophrenia suggesting differential susceptibility of selected neural pathways to immune mediators.

Imaging neuroinflammation in gray and white matter in schizophrenia: an in-vivo PET study with [18F]-FEPPA

Neuroinflammation and abnormal immune responses have been implicated in schizophrenia (SCZ). Past studies using positron emission tomography (PET) that examined neuroinflammation in patients with SCZ in vivo using the translocator protein 18kDa (TSPO) target were limited by the insensitivity of the first-generation imaging agent [(11)C]-PK11195, scanners used, and the small sample sizes studied. Present study uses a novel second-generation TSPO PET radioligand N-acetyl-N-(2-[(18)F]fluoroethoxybenzyl)-2-phenoxy-5-pyridinamine ([(18)F]-FEPPA) to evaluate whether there is increased neuroinflammation in patients with SCZ. A cross-sectional study was performed using [(18)F]-FEPPA and a high-resolution research tomograph (HRRT). Eighteen patients with SCZ with ongoing psychotic symptoms and 27 healthy volunteers (HV) were recruited from a tertiary psychiatric clinical setting and the community, respectively. All participants underwent [(18)F]-FEPPA PET and magnetic resonance imaging, and PET data were analyzed to obtain [(18)F]-FEPPA total volume of distribution (VT) using a 2-tissue compartment model with an arterial plasma input function, as previously validated. All subjects were classified as high-, medium- or low-affinity [(18)F]-FEPPA binders on the basis of rs6971 polymorphism, and genotype information was incorporated into the analyses of imaging outcomes. No significant differences in neuroinflammation indexed as [(18)F]-FEPPA VT were observed between groups in either gray (F(1,39) = 0.179, P = .674) or white matter regions (F(1,38) = 0.597, P = .445). The lack of significant difference in neuroinflammation in treated patients with SCZ in the midst of a psychotic episode and HV suggests that neuroinflammatory processes may take place early in disease progression or are affected by antipsychotic treatment.

Association between ANKK1 (rs1800497) and LTA (rs909253) Genetic Variants and Risk of Schizophrenia

Limited research has assessed associations between schizophrenia and genetic variants of the ankyrin repeat and kinase domain containing 1 (ANKK1) and lymphotoxin-alpha (LTA) genes among individuals of Middle Eastern ancestry. Here we present the first association study investigating the ANKK1 rs1800497 (T>C) and LTA rs909253 (A>G) single-nucleotide polymorphisms in an Egyptian population. Among 120 patients with DSM-IV and PANSS (Positive and Negative Syndrome Scale) assessments of schizophrenia and 100 healthy controls, we determined the genotypes for the polymorphisms using endonuclease digestion of amplified genomic DNA. Results confirmed previous findings from different ethnic populations, in that the rs1800497 and rs909253 polymorphisms were both associated with risk of schizophrenia. Differences between the genotypes of cases and controls were strongly significant (P = 0.0005 for rs1800497 and P = 0.001 for rs909253). The relative risk to schizophrenia was 1.2 (P = 0.01) for the C allele and 0.8 (P = 0.04) for the G allele. The CC, GG, and combined CC/AA genotypes were all more frequent in cases than in controls. These results support an association between ANKK1 and LTA genetic markers and vulnerability to schizophrenia and show the potential influence of just one copy of the mutant C or G allele in the Egyptian population.

A randomized placebo-controlled pilot study of pravastatin as an adjunctive therapy in schizophrenia patients: effect on inflammation, psychopathology, cognition and lipid metabolism

OBJECTIVE

The aim of this study was to investigate the role of pravastatin, as an adjunctive therapy, on inflammatory markers, lipid and glucose metabolism, psychopathology, and cognition in subjects with schizophrenia and schizoaffective disorder.

METHODS

Schizophrenia or schizoaffective subjects (N=60) were randomized to receive either a 12-week supply of pravastatin 40 mg/day or placebo treatment. Anthropometric measures, lipids and glucose metabolism, inflammatory markers, psychopathology and cognitive performance were assessed at baseline, 6 weeks and 12 weeks.

RESULTS

Pravastatin use was associated with a significant decrease in total cholesterol, low density lipoprotein (LDL) cholesterol and LDL particle number levels, but was not associated with any significant changes in cognition or psychopathology in the participants, except a significant decrease in the Positive and Negative Syndrome Scale (PANSS) positive symptom score from baseline to week 6. However, this decrease failed to remain significant at 12 weeks. Interestingly, triglycerides, LDL-cholesterol, total cholesterol, LDL particle number, small LDL particle number, large very low density lipoprotein (VLDL) particle number and C-reactive protein (CRP) followed a similar pattern at 6 and 12 weeks as psychopathology.

CONCLUSIONS

These results suggest that a randomized trial with a larger sample size and a higher dosage of pravastatin would be helpful in further evaluating the anti-inflammatory properties of pravastatin, its association with improvements in cognitive symptoms, and its potential to reduce positive and negative symptoms associated with schizophrenia or schizoaffective disorders.

The SHP-1 expression is associated with cytokines and psychopathological status in unmedicated first episode schizophrenia patients

BACKGROUND

Recent lines of research have boosted awareness of the immunological facets of schizophrenia. However, associations with protein tyrosine phosphatase regulators have never been reported. The aim of our study was to investigate the expression and promoter status methylation of phosphatase SHP-1, a key negative regulator of the inflammatory process, in Peripheral blood mononuclear cells (PBMCs) of Schizophrenic patients.

METHODS

We enrolled fifty-four (28 men and 26 women) unmedicated first episode subjects (SC) who met DSM-IV and thirty-eight (22 men and 16 women) healthy controls (HC). The SC psychopathological status was assessed using the Positive and Negative Syndrome Scale. We evaluated SHP-1 expression by Quantitative Real-time PCR (qPCR) and Western blotting (WB) methods and promoter status methylation through PCR bisulfate. IKK/NFkB signaling was detected by WB, and medium and plasma levels of pro-inflammatory cytokines (IL-1β, IL-2, and TNF-α) by the ELISA method. SHP-1 was silenced by treating cells with specific siRNA.

RESULTS

We found a significantly lower level of SHP-1 gene expression in PBMCs from SC vs. HC, consistently with which the promoter region analyzed presented significant hypermethylation. Silencing of SHP-1 expression induced higher activation of IKK/NF-kB signaling and pro-inflammatory cytokine production in ex vivo PBMCs from both SC and HC. Linear regression among patients generated a model in which SHP-1 expression explained 30% of the clinical negative symptom variance (adjusted R(2)=0.30, ANOVA p<0.001).

CONCLUSIONS

Our findings are the first to suggest that impairment of SHP-1 expression is involved in the physiopathology of schizophrenia, opening fruitful new avenues for ameliorating treatment at least of negative symptoms.

C-reactive protein levels in schizophrenia: a review and meta-analysis

There is an impression in the literature that schizophrenia is associated with increased inflammation, including abnormal blood levels of the acute phase reactant C-reactive protein (CRP). We performed a meta-analysis of blood CRP levels to estimate the overall effect size, as well as a pooled analysis of the prevalence of an elevated CRP level in patients with schizophrenia and related disorders. We identified articles by searching PubMed, PsycInfo, and ISI, and the reference lists of identified studies. Eight studies met the inclusion criteria for the meta-analysis, and five studies were included in the pooled analysis. CRP levels were significantly increased in patients compared to controls (effect size=0.45, 95% confidence interval 0.34-0.55, p<0.001). There was a 28% prevalence of an elevated CRP level in patients with schizophrenia and related disorders. Our results support a growing body of literature that schizophrenia is associated with increased inflammation, although many studies did not control for potential confounding factors such as BMI and smoking. Given the high prevalence of elevated CRP, metabolic syndrome, and premature cardiovascular mortality, our findings also suggest that measurement of blood CRP levels may be germane to the clinical care of patients with schizophrenia and related disorders.

Proof-of-concept randomized controlled trial of pregnenolone in schizophrenia

RATIONALE

Preclinical and clinical data suggest that pregnenolone may be a promising therapeutic in schizophrenia. Pregnenolone is neuroprotective and enhances learning and memory, myelination, and microtubule polymerization. Treatment with pregnenolone elevates allopregnanolone (a neurosteroid that enhances GABAA receptor responses) and pregnenolone sulfate (a positive NMDA receptor modulator). Pregnenolone could thus potentially mitigate GABA dysregulation and/or NMDA receptor hypofunction in schizophrenia via metabolism to other neurosteroids.

OBJECTIVE

The objective of this study is to conduct a randomized controlled trial of adjunctive pregnenolone in schizophrenia.

METHODS

Following a placebo lead-in, 120 participants were randomized to pregnenolone or placebo for 8 weeks (Institute for Mental Health, Singapore). Primary endpoints were changes in MATRICS Consensus Cognitive Battery (MCCB) composite scores (cognitive symptoms), UCSD Performance-based Skills Assessment-Brief (UPSA-B) composite scores (functional capacity), and Scale for Assessment of Negative Symptoms (SANS) total scores (negative symptoms). A modified intent-to-treat analysis approach was utilized.

RESULTS

No significant changes compared to placebo were demonstrated in composite MCCB scores. In contrast, participants randomized to pregnenolone (n = 56) demonstrated greater improvements in functional capacity (UPSA-B composite changes) compared to placebo (n = 55), p = 0.03. Pregnenolone was also superior to placebo in the communication subscale of the UPSA-B (p < 0.001). Serum pregnenolone changes post-treatment were correlated with UPSA-B composite score changes in females (r s = 0.497, p < 0.042, n = 17) but not in males. Mean total SANS scores were very low at baseline and did not improve further post-treatment. Pregnenolone was well-tolerated.

CONCLUSIONS

Pregnenolone improved functional capacity in participants with schizophrenia, but did not improve cognitive symptoms over an 8-week treatment period. Neurosteroid changes correlated with functional improvements in female participants. Neurosteroid interventions may exhibit promise as new therapeutic leads for schizophrenia.

Association between exposure to HSV1 and cognitive functioning in a general population of adolescents. The TRAILS study

BACKGROUND

Infections with different herpes viruses have been associated with cognitive functioning in psychiatric patients and healthy adults. The aim of this study was to find out whether antibodies to different herpes viruses are prospectively associated with cognitive functioning in a general adolescent population.

METHODS

This study was performed in TRAILS, a large prospective general population cohort (N = 1084, 54% female, mean age 16.2 years (SD 0.6)). At age 16, immunoglobulin G antibodies against HSV1, HSV2, CMV and EBV were measured next to high sensitive C-Reactive Protein (hsCRP). Two years later, immediate memory and executive functioning were assessed using the 15 words task and the self ordered pointing task. Multiple linear regression analysis with bootstrapping was performed to study the association between viral infections and cognitive function, adjusting for gender, socioeconomic status, ethnicity, and cannabis use.

RESULTS

Presence of HSV1 antibodies was associated with memory function ((B = -0.272, 95% CI = -0.556 to -0.016, p = 0.047)), while the association with executive functioning did not reach statistical significance (B = 0.560, 95% CI is -0.053 to 1.184, p = 0.075). The level of HSV1 antibodies was associated with both memory function (B = -0.160, 95% CI = -0.280 to -0.039, p = 0.014) and executive functioning (B = 0.296, 95% CI = 0.011 to 0.578, p = 0.046). Other herpes viruses and hsCRP were not associated with cognitive functioning.

CONCLUSIONS

Both presence and level of HSV1 antibodies are prospectively associated with reduced cognitive performance in a large cohort of adolescents.

Increased M1/decreased M2 signature and signs of Th1/Th2 shift in chronic patients with bipolar disorder, but not in those with schizophrenia

We here present data on immune gene expression of chemokines, chemokine receptors, cytokines and regulatory T-cell (T-reg) markers in chronic patients suffering from either schizophrenia (SCZ, N=20) or bipolar disorder (BD=20) compared with healthy controls (HCs, N=20). We extracted RNA from peripheral blood mononuclear cells and performed real-time (RT)-PCR to measure mRNA levels of chemokines, chemokine receptors, cytokines and T-reg markers. All the analyses were Bonferroni-corrected. The classical monocyte activation (M1) markers il6, ccl3 were significantly increased in BD as compared with both HC and SCZ patients (P=0.03 and P=0.002; P=0.024 and P=0.021, respectively), whereas markers of alternative (M2) monocyte activation ccl1, ccl22 and il10 were coherently decreased (controls: P=0.01, P=0.001 and P=0.09; SCZ subjects: P=0.02, P=0.05 and P=0.011, respectively). Concerning T-cell markers, BD patients had compared with HC downregulated ccr5 (P=0.02) and upregulated il4 (P=0.04) and compared with both healthy and SCZ individuals downregulated ccl2 (P=0.006 and P=0.003) and tgfβ (P=0.004 and P=0.007, respectively). No significant associations were found between any immune gene expression and clinical variables (prior hospitalizations, Brief Psychiatric Rating Scale, medications' dosages and lifetime administration). Although some markers are expressed by different immune cell types, these findings suggest a coherent increased M1/decrease M2 signature in the peripheral blood of BD patients with potential Th1/Th2 shift. In contrast, all the explored immune marker levels were preserved in SCZ. Further larger studies are needed to investigate the relevance of inflammatory response in BD, trying to correlate it to psychopathology, treatment and outcome measures and, possibly, to brain connectivity.

Add-on clinical effects of simvastatin and ondansetron in patients with schizophrenia stabilized on antipsychotic treatment: pilot study

OBJECTIVES

There is some evidence that anti-inflammatory treatment may have beneficial effects in schizophrenia and major depression. Statins are cholesterol-lowering agents but have been found to be anti-inflammatory and also decrease C-reactive protein (CRP). Ondansetron is a serotonin (5-HT3) receptor antagonist widely used to prevent nausea and vomiting in patients receiving chemotherapy for cancer. Small studies have suggested that adjunctive ondansetron is efficacious against schizophrenia symptoms. We carried out a feasibility study in schizophrenia patients (within 5 years of first diagnosis) to explore the adjunctive use of simvastatin and ondansetron on positive, negative and general psychopathology.

METHODS

This was a 12-week rater-blind placebo-controlled study. A total of 36 patients with DSM-IV diagnosis of schizophrenia were recruited, 12 in each arm. Patients were assessed at baseline and at 12 weeks using Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression (CGI) scale, Global Assessment of Functioning (GAF) and Abnormal Involuntary Movement Scale (AIMS).

RESULTS

Both simvastatin and ondansetron provide some evidence of a reduction in symptoms compared with treatment as usual (TAU) on PANSS total score, although this was not statistically significant. In the secondary analyses, no significant differences were seen on CGI, GAF and AIMS.

CONCLUSIONS

Anti-inflammatory treatments have been shown to have some beneficial effects in schizophrenia. Both simvastatin and ondansetron provide some evidence of a reduction in symptoms compared with TAU. This study has led to a larger Stanley Medical Research Institute (SMRI)-funded, double-blind, randomized control trial.

Inflammatory biomarker profiles of mental disorders and their relation to clinical, social and lifestyle factors

In the last few decades, mental health research has increasingly provided evidence supporting the role of inflammation in pathogenesis, course and treatment of mental disorders. With such a steep incline of research, resulting in a wealth of emerged findings, it has become difficult to follow developments within the field. The present review sets out to present the recent developments and to give an overview of the inflammatory profiles of depression, psychosis and bipolar disorder, as well as variations within these disorders. Moreover, mediating factors such as social environment and childhood experience are discussed, both in terms of their potential in elucidating the complex interface between the inflammation and other closely related biological systems, as well as the possibly confounding impact of various lifestyle factors. Whilst many issues in this fascinating area of research remain to be fully understood and elaborated, all current evidence suggests that inflammation plays a key role in mental disorders and may open up novel avenues for clinical treatment.

Evidence for an immune role on cognition in schizophrenia: a systematic review

Objective:

Recent evidence has associated immune and inflammatory changes to cognitive performance in many diseases, including schizophrenia. Since this is a new research field where concepts are not yet solid and new questions and hypothesis are still arising, the present study aimed at summarizing the available clinical data associating schizophrenia, cognition and inflammation/immune function.

Methods:

A systematic review of the literature was made by searching the following terms in Medline: “schizophrenia or psychosis or psychotic” AND “inflamm* or immun* or cytokine or IL-* or TNF-* or kynureni* or KYNA”, AND “cognit* or attention or memory or executive function”.

Results:

Seventy five papers were identified using the selected terms, and seven papers were included in the review. Papers excluded focused mainly on basic research or other neuropsychiatric disorders.

Conclusions:

Recent findings link inflammatory markers to cognition in schizophrenia, suggesting that inflammation is associated with worst cognitive performance. Microglial activation, monoaminergic imbalance, brain abnormalities and the kynurenine pathway are possible mechanisms underlying cognitive impairment in schizophrenia. Clinical trials with addition of immunomodulatory drugs have shown promising results, opening new windows to tackle cognition in schizophrenia.

Role of C-reactive protein in schizophrenia: an overview

Over the years, schizophrenia is speculated to be associated with immune or inflammatory reactions mediated by cytokines. It is proposed that chronic inflammation might damage the micro-vascular system of brain and hamper cerebral blood flow. Scientific evidence suggests that an increase of stress hormone like norepinephrine may activate the inflammatory arm of the immune system and trigger the expression of genes that cause chronic, low-grade inflammation. Thus, studies were conducted to decipher the potentiality of CRP as a marker for inflammation in schizophrenia. This article reviews the findings of CRP in schizophrenia, and the limitations of the previous studies have been discussed. The importance of simultaneous study of CRP modulating cytokines and CRP gene polymorphism in the study of serum or plasma level of CRP has been emphasized.

Psychopharmacological treatment of neurocognitive deficits in people with schizophrenia: a review of old and new targets

Neurocognitive impairments significantly contribute to disability and the overall clinical picture in schizophrenia spectrum disorders. There has therefore been a concerted effort, guided by the discovery of neurotransmitter and synaptic systems in the central nervous system, to develop and test compounds that may ameliorate neurocognitive deficits. The current article summarizes the results of efforts to test neurocognitive-enhancing agents in schizophrenia. Overall, existing clinical trials provide little reason to be enthusiastic about the benefits of psychopharmacological agents at enhancing neurocognition in schizophrenia-a state of affairs that may reflect the inadequacy of single neurotransmitter or receptor models. The etiologic and phenomenological complexity of neurocognitive deficits in schizophrenia may be better served by psychopharmacological agents that (i) target neurotransmitter systems proximal in the causal chain to neurocognitive deficits; (ii) enhance distal survival processes in the central nervous system-neurogenesis, neuronal growth, synaptogenesis, and connectivity; and (iii) counteract the negative effects of aberrant neurodevelopment in schizophrenia, such as neuroinflammation and oxidative stress. Future efforts to develop psychopharmacological agents for neurocognitive impairment in schizophrenia should reflect the knowledge of its complex etiology by addressing aberrations along its causal chain. Clinical trials may benefit methodologically from (i) an appreciation of the phenomenological heterogeneity of neurocognitive deficits in schizophrenia; (ii) a characterization of the predictors of treatment response; and (iii) a recognition of issues of sample size, statistical power, treatment duration, and dosing.

Inflammatory cytokine network in schizophrenia

OBJECTIVES

The purpose of this review is to analyse, sum up and discuss the available literature on the role of inflammation and inflammatory cytokines in the pathogenesis of schizophrenia.

METHODS

An electronic literature search of peer-reviewed English language articles using Pubmed was undertaken. These articles together with those published by us provided the background for the present review.

RESULTS

An overview of the available literature on this issue clearly demonstrated the alterations in mRNA and protein expression levels of several proinflammatory and chemotactic cytokines in patients with schizophrenia. Importantly, some of these changes are genetically determined. It was noteworthy that, depending on the study population, some variations of the data obtained are detected.

CONCLUSIONS

Altered inflammatory cytokine production, both genetically and environmentally determined, is implicated in schizophrenia and contributes to disease-associated low-grade systemic inflammation. Proinflammatory and chemotactic cytokines and their receptors may represent additional therapeutic targets for treatment of schizophrenia.

Increased serum interleukin-6 levels in early stages of psychosis: associations with at-risk mental states and the severity of psychotic symptoms

Schizophrenia patients experience activated inflammatory responses, but little is known about the presence of such inflammatory processes at or prior to disease onset. We measured interleukin-6 (IL-6) and C-reactive protein (CRP) serum levels and plasma fibrinogen in 17 at-risk mental state (ARMS) subjects, 77 patients with psychotic disorder (PD) and 25 healthy control subjects (HC). ARMS subjects were followed-up, and transition to psychosis was registered. IL6 rs1800795 SNP was genotyped, as IL-6 levels may be influenced by this genetic variant. We did not observe significant differences in the IL6 rs1800795 SNP genotype frequencies between the groups. ARMS subjects exhibited significantly higher IL-6 levels than did controls (p=0.019). In subjects not taking cannabis, we found that patients diagnosed with ARMS or PD exhibited increased IL-6 levels when compared with HC (p=0.004). In both ARMS and PD subjects, IL-6 levels were positively associated with negative symptoms. However, with respect to positive psychotic symptoms, a different relationship was observed in the ARMS and PD groups (positive relationship in ARMS; negative relationship in PD). These findings could not be attributed to confounding variables, including gender, body mass index (BMI), tobacco consumption or the rs1800795 genotype. Six of 17 ARMS subjects (35%) exhibited a transition to psychosis during the follow-up period of 26 months. ARMS subjects who developed psychosis exhibited increased median IL-6 levels compared with those who did not transition (0.61 vs. 0.35pg/mL). However, this difference was not statistically significant, which could be explained by a lack of statistical power due to the small sample size. Our results suggest that IL-6 may be a biomarker for early psychotic symptoms; however, further studies in larger samples are needed to confirm this result.

HLA associations in schizophrenia: are we re-discovering the wheel?

Associations between human leukocyte antigen (HLA) polymorphisms on chromosome 6p and schizophrenia (SZ) risk have been evaluated for over five decades. Numerous case-control studies from the candidate gene era analyzed moderately sized samples and reported nominally significant associations with several loci in the HLA region (sample sizes, n = 100-400). The risk conferred by individual alleles was modest (odds ratios < 2.0). The basis for the associations could not be determined, though connections with known immune and auto-immune abnormalities in SZ were postulated. Interest in the HLA associations has re-emerged following several recent genome-wide association studies (GWAS); which utilized 10- to 100-fold larger samples and also identified associations on the short arm of chromosome 6. Unlike the earlier candidate gene studies, the associations are statistically significant following correction for multiple comparisons. Like the earlier studies; they have modest effect sizes, raising questions about their utility in risk prediction or pathogenesis research. In this review, we summarize the GWAS and reflect on possible bases for the associations. Suggestions for future research are discussed. We favor, in particular; efforts to evaluate local population sub-structure as well as further evaluation of immune-related variables in future studies.

Role of immunological factors in the pathophysiology and diagnosis of bipolar disorder: comparison with schizophrenia

Several lines of evidence point to the key role of neurobiological mechanisms and shared genetic background in schizophrenia and bipolar disorder. For both disorders, neurodevelopmental and neurodegenerative processes have been postulated to be relevant for the pathogenesis as well as dysregulation of immuno-inflammatory pathways. Inflammation is a complex biological response to harmful stimuli and it is mediated by cytokines cascades, cellular immune responses, oxidative factors and hormone regulation. Cytokines, in particular, are supposed to play a critical role in infectious and inflammatory processes, mediating the cross-talk between the brain and the immune system; they also possibly contribute to the development of the central nervous system. From this perspective, even though mixed results have been reported, it seems that both schizophrenia and bipolar disorder are associated with an imbalance in inflammatory cytokines; in fact, some of these could represent biological markers of illness and could be possible targets for pharmacological treatments. In light of these considerations, the purpose of the present paper was to provide a comprehensive and critical review of the existing literature about immunological abnormalities in bipolar disorder with particular attention to the similarities and differences with schizophrenia.

Efficacy of anti-inflammatory agents to improve symptoms in patients with schizophrenia: an update

BACKGROUND

The inflammatory hypothesis of schizophrenia is not new, but recently it has regained interest because more data suggest a role of the immune system in the pathogenesis of schizophrenia. If increased inflammation of the brain contributes to the symptoms of schizophrenia, reduction of the inflammatory status could improve the clinical picture. Lately, several trials have been conducted investigating the potential of anti-inflammatory agents to improve symptoms of schizophrenia. This study provides an update regarding the efficacy of anti-inflammatory agents on schizophrenic symptoms in clinical studies performed so far.

METHODS

An electronic search was performed using PubMed, Embase, the National Institutes of Health web site http://www.clinicaltrials.gov, Cochrane Schizophrenia Group entries in PsiTri, and the Cochrane Database of Systematic Reviews. Only randomized, double-blind, placebo-controlled studies that investigated clinical outcome were included.

RESULTS

Our search yielded 26 double-blind randomized controlled trials that provided information on the efficacy on symptom severity of the following components: aspirin, celecoxib, davunetide, fatty acids such as eicosapentaenoic acids and docosahexaenoic acids, estrogens, minocycline, and N-acetylcysteine (NAC). Of these components, aspirin (mean weighted effect size [ES]: 0.3, n = 270, 95% CI: 0.06-0.537, I(2) = 0), estrogens (ES: 0.51, n = 262, 95% CI: 0.043-0.972, I(2) = 69%), and NAC (ES: 0.45, n = 140, 95% CI: 0.112-0.779) showed significant effects. Celecoxib, minocycline, davunetide, and fatty acids showed no significant effect.

CONCLUSION

The results of aspirin addition to antipsychotic treatment seem promising, as does the addition of NAC and estrogens. These 3 agents are all very broadly active substances, and it has to be investigated if the beneficial effects on symptom severity are indeed mediated by their anti-inflammatory aspects.

Association of metabolic syndrome and inflammation with neurocognition in patients with schizophrenia

The aim of this study is to assess the relationships of metabolic syndrome (MetS) and inflammation with neurocognition in schizophrenia. In this cross-sectional study, we included patients with diagnosis of schizophrenia according to the DSM-IV-TR criteria. We collected socio-demographic information, clinical characteristics, anthropometric measurements, blood tests, and neurocognition measures. A multivariate analysis using multiple linear regressions was performed to determine variables that are potentially associated with neurocognition. The analyses were repeated using MetS as a dichotomised variable (< and ≥ 3 MetS criteria), a continuous variable (number of MetS criteria present), and for each component of MetS. One hundred and sixty-eight outpatients participated in our study. The prevalence of MetS was 27.4%. An association was found between the number of MetS criteria present and cognitive impairment. Among the different components of MetS, hypertriglycerides and abdominal obesity were the only factors associated with cognitive impairment. Other factors, such as smoking and alcohol dependence or abuse, also revealed a significant relationship, whereas inflammation was not associated with cognitive impairment. In conclusion, our findings suggest that MetS, alcohol use and non-smoking status are associated with cognitive impairment. These findings may support complementary therapeutic approaches in cognitive remediation that lessen the severity of cognitive impairment in schizophrenia.

Exposure to herpes simplex virus, type 1 and reduced cognitive function

Herpes simplex virus, type 1 (HSV-1) causes cold sores, keratitis and rarely, fatal encephalitis. The infection is lifelong, with sensory ganglia serving as reservoirs of latent infection. Recently, exposure to HSV-1 has also been repeatedly associated with reduced cognitive function among healthy individuals without prior encephalitis. Though HSV-1 does not elevate risk for schizophrenia (SZ) per se, exposure is likewise associated with impaired cognitive functions among SZ patients. The range of cognitive changes observed in HSV-1 exposed persons has not been investigated systematically, nor is it known whether interaction between HSV-1 exposure and SZ related factors contributes to the impairment among SZ patients. Persons with or without schizophrenia/schizophreniform disorder (N = 298 total, DSM IV criteria) were assessed for HSV-1 exposure using serum HSV-1 antibody titers. The Penn Computerized Neurocognitive battery was used to assess eight cognitive domains with respect to accuracy and speed. There were no significant case-control differences in HSV-1 exposure. The SZ/schizophreniform disorder cases were significantly impaired in all cognitive domains compared with the controls. HSV-1 exposure was also associated with reduced cognitive function in the entire sample, but the magnitude of the effects and their patterns differed from the SZ related changes. Further, statistically significant interactions between HSV-1 exposure and SZ case status were not detected. HSV-1 exposure does not elevate risk for SZ, but it is associated with reduced function in specific cognitive domains regardless of SZ diagnostic status. An 'epidiagnostic' model for the association is proposed to explain the results.

Elevated C-reactive protein and cognitive deficits in individuals with bipolar disorder

BACKGROUND

Some individuals with bipolar disorder have cognitive deficits even when euthymic. In previous studies, we found an association between elevated levels of C-reactive protein (CRP), a marker of inflammation, and reduced cognitive functioning in schizophrenia. This issue has not been examined in bipolar disorder.

METHODS

We measured the levels of high sensitivity CRP in serum samples from 107 individuals with bipolar disorder. Cognitive functioning was measured with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Trail Making Test Part A and WAIS Information and Letter Number Sequencing. We estimated the odds of RBANS scores <=70 for participants whose CRP levels were above the 75th and the 90th percentile of the level of non-psychiatric controls. We also examined the association between cognitive scores and CRP levels. Covariates included demographic factors, mood symptom severity, cigarette smoking status, and body mass index.

RESULTS

There was a significantly increased odds of low RBANS total score for individuals who had a CRP level higher than the 90th percentile (OR=4.32, p=.018) and the 75th percentile (OR=3.07, p=.04)) of the control group. There was an inverse relationship between CRP levels and performance on RBANS total (t=-2.48, p=.015); RBANS immediate memory (t=-2.16, p=.033); RBANS attention (t=-2.18, p=.032); RBANS language (t=-2.13, p=.036); Trail Making A (t=-2.39, p=.019).

LIMITATIONS

Factors which we did not measure such as diet, allergen exposure, and underlying autoimmune disorders may contribute to CRP levels.

CONCLUSIONS

Inflammation may play a major role in the cognitive deficits associated with bipolar disorder.

Increased high-sensitivity C-reactive protein levels in Taiwanese schizophrenic patients

INTRODUCTION

Schizophrenia is associated with the activation of the immune/inflammatory system. C-reactive protein (CRP), a positive acute phase protein, may be associated with schizophrenia and antipsychotic treatment.

METHODS

The serum high-sensitivity CRP (hsCRP) levels of 36 schizophrenic patients undergoing clozapine, olanzapine or risperidone treatment and 36 sex-matched healthy subjects were collected. The difference in hsCRP levels between the schizophrenic and the control groups was estimated using ancova. anova was performed to examine the differences in the hsCRP levels between three antipsychotic groups (clozapine, olanzapine and risperidone).

RESULTS

ancova adjusted for age and body mass index (BMI) revealed a significant increase in the hsCRP levels in the schizophrenic group (1.4 mg/L, SD =1.5 mg/L) in comparison with the control group (0.9 mg/L, SD = 1.4 mg/L) (P = 0.013). anova revealed no statistical difference of age, BMI and hsCRP in three antipsychotic groups (P = 0.83, 0.90 and 0.71, respectively).

DISCUSSION

The elevation of CRP level is seen in chronic schizophrenia under antipsychotic treatment; however, studies with a larger sample size are required to confirm these results.

Future perspectives on the treatment of cognitive deficits and negative symptoms in schizophrenia

Drug discovery based on classic models for cognitive impairment and negative symptoms of schizophrenia have met with only modest success. Because cognitive impairment and negative symptoms may result from disruptions in neurodevelopment, more complex developmental models that integrate environmental and genetic risk factors are needed. In addition, it has become clear that biochemical pathways involved in schizophrenia form complex, interconnected networks. Points at which risk factors converge, such as brain-derived neurotrophic factor (BDNF) and protein kinase B (AKT), and from which processes involved in neuroplasticity diverge, are of particular interest for pharmacologic interventions. This paper reviews elements of neurodevelopmental models for cognitive deficits and negative symptoms of schizophrenia with the aim of identifying potential targets for interventions.

Human endogenous retrovirus type W (HERV-W) in schizophrenia: a new avenue of research at the gene-environment interface

OBJECTIVES

Provide a synthetic review of recent studies evidencing an association between human endogenous retrovirus-W (HERV-W) and schizophrenia.

METHODS

Bibliography analysis and contextual synthesis.

RESULTS

Epidemiological studies suggest that the aetiology of schizophrenia is complex and involves a complex interplay of genetic and environmental factors such as infections. Eight percentof the human genome consists of human endogenous retroviruses (HERV), and this part of the genome was previously thought to be without importance, but new research has refuted this. HERVs share similarities with viruses and it is assumed that HERVs are present in the genome as a result of retroviruses infecting germ line cells many million years ago. A specific type of HERVs, called HERV-W, has through several recent studies been associated with schizophrenia. Elevated transcription of HERV-W elements has been documented, and antigens of HERV-W envelope and capsid proteins have been found in blood samples from patients. Viruses that have been implicated in pathology of schizophrenia, such as herpes and influenza, have been shown to activate HERV-W elements, and such activation has been associated with elevated biomarkers of systemic inflammation. New research indicates that HERV-W may be an important genetic factor interplaying with the environmental risk factor of infections and that, through this, HERV-W may be important for disease pathogenesis.

CONCLUSIONS

A lifelong scenario of a detrimental interaction between infectious agents and HERV-W genes may decipher the actual development and course of schizophrenia. Further research is needed to find out if specific treatment strategies could reduce the expression of HERV-W and if this will be associated with remission.

Neonatal levels of acute phase proteins and later risk of non-affective psychosis

Mounting evidence suggests that immune disturbances in early life may be implicated in the etiology of non-affective psychoses. Our aim was to assess the levels of neonatal acute phase proteins (APPs), central to innate immune function as well as central nervous system development, in neonatal dried blood spots and their association with later risk of non-affective psychoses. This case-control study included 196 individuals with a verified register-based diagnosis of non-affective psychosis and 502 controls matched on age, sex and hospital of birth. Concentrations of nine different APPs were measured in eluates from dried blood spots using a bead-based multiplex assay. Odds ratios (OR) for non-affective psychoses were calculated for log(2)-transformed (continuous) as well as tertiles of APP concentrations. In continuous analysis, higher concentrations of two APPs, tissue plasminogen activator (tPA; OR: 0.90, 95% confidence interval (CI): 0.85-0.96) and serum amyloid P (SAP; OR: 0.88, 95% CI: 0.78-0.99) were protective in terms of risk of non-affective psychosis. These relationships were not affected by the addition of covariates relevant to maternal health, pregnancy and delivery to the model. Tertile analysis confirmed a protective relationship for higher levels of tPA and SAP, as well as for procalcitonin (highest tertile OR: 0.54, 95% CI:0.32-0.91). Our results suggest that persons who develop non-affective psychoses have lower levels of certain APPs at the time of birth. These differences may render individuals more susceptible to infectious diseases or cause deficiencies in pathways critical for neurodevelopment.

C-Reactive Protein Level and its Relationship with Suicide Risk and Alexithymia among Newly Diagnosed, Drug-Naïve Patients with Non-Affective Psychosis

The aim of the present study was to evaluate C-Reactive Protein (CRP) levels in newly diagnosed drug-naïve patients with non-affective psychosis, testing the hypotheses that in such patients serum CRP levels would be higher than in healthy controls and related to more severe psychopathology, suicide risk and alexithymia. CRP levels of 30 adult patients and 30 sex- and age-matched healthy controls were evaluated. Patients were tested with the Scale of Suicide Ideation (SSI), the Toronto Alexithymia Scale (TAS-20), the Scale for the Assessment of Positive and Negative Symptoms (SAPS and SANS) and the Calgary Depression Scale for Schizophrenia (CDSS). Higher suicide risk patients showed higher CRP levels than lower suicide risk patients and healthy controls. Moreover, such patients showed higher SAPS, SANS and CDSS scores than lower suicide risk patients. In linear regression model, CRP was significantly associated with higher SSI and TAS-20 scores. The results of the present study support the notion that CRP, suicide risk and alexithymia are strictly linked in newly diagnosed, drug-naïve patients with non-affective psychosis, independently of depressive symptoms or general psychopathology. Limitations are discussed.

Comparison of peripheral and central schizophrenia biomarker profiles

We have recently shown that a molecular biomarker signature comprised of inflammatory, hormonal and growth factors occurs in the blood serum from first onset schizophrenia patients. Here, we use the same platform to investigate post mortem brain tissue (Brodmann area 10) from schizophrenia patients who were mainly chronically ill and drug treated. Twenty-one analytes are differentially expressed in post-mortem brain tissue. Comparison with our previous mRNA profiling studies of the same patient samples in another frontal cortical area showed that 9 of these molecules were also altered at the transcriptional level. Furthermore, 9 of the molecules were also altered in serum from living first onset schizophrenia patients compared to controls. We propose a model in which the brain and periphery are coordinated through hormones and other regulatory molecules released into the blood via the diffuse neuroendocrine system. These findings provide further evidence for the systemic nature of schizophrenia and give added validity to the concept that schizophrenia can be investigated through studies of blood-based biomarkers.

Role of Omega-3 fatty acids in preventing metabolic disturbances in patients on olanzapine plus either sodium valproate or lithium: a randomized double-blind placebo-controlled trial

Background

Metabolic and cardiovascular side effects have been noted with the use of second generation antipsychotics (SGAs) and mood stabilizers. Since Omega-3 fatty acids have been known to prevent some cardiovascular risks, this preliminary study was designed to evaluate the cardiovascular benefits of omega-3 when added to the combinations of olanzapine with mood stabilizers.

Methods

This study was a randomized, double-blind, placebo-controlled, within-subject trial in adult psychiatric patients who were receiving olanzapine combined with lithium (Li) or valproate sodium (VPA). Omega-3 as fish oil with less than 1 g/day of EPA/DHA or its placebo was added to patients’ olanzapine and mood stabilizer regimens for 6 weeks. Metabolic parameters including anthropometric variables, lipid profile, metabolic syndrome indices, C-reactive protein, fibrinogen and lipoprotein (a) [(Lp) (a)] were assessed for participants.

Results

Forty one participants completed this study; 20 patients received omega-3 and 21 patients received placebo, added to their regimen of SGA and mood stabilizer. Omega-3 addition did not modulate anthropometric, metabolic syndrome and lipid parameter changes in 6 weeks. However, fibrinogen levels significantly decreased, Lp (a) did not increase and non-high-density lipoprotein cholesterol (non-HDL-C) did not go beyond its target level after omega-3 supplementation. Additionally, a significant inter-group effect was noted for Lp(a).

Conclusions

This study suggests that use of short-term omega-3 supplementation added to a combined regimen of olanzapine and mood stabilizer may have a small modulating effect on some cardiovascular risk factors. Trials in longer periods of time and with larger number of patients are needed to further evaluate the effects of omega-3 supplements on preventing cardiovascular risk factors.

This trial is registered at irct.ir and its Identifier is as following: IRCT138712231764N1

Association between C-reactive protein and cognitive deficits in elderly men and women: a meta-analysis

BACKGROUND

Certain risk factors for cognitive decline appear modifiable. A potentially modifiable marker of inflammation, C-reactive protein may be associated with cognitive deficits, although not all studies have found a relationship between C-reactive protein and cognitive ability. Further, few research papers have examined whether gender may affect any association between C-reactive protein and cognitive deficit.

METHODS

To better understand the association between C-reactive protein, cognitive deficit, and gender in elderly people, we meta-analyzed cross-sectional studies that reported cognitive ability assessed by the Mini-Mental State Examination or an equivalent measure, C-reactive protein concentrations, and gender.

RESULTS

While we identified no studies containing only male subjects, the two identified studies containing both female and male subjects (n = 2,525) showed an effect size for cognition of -0.1809 (95% confidence interval, -0.2652 to -0.0967, p = 0.000025) between high and low C-reactive-protein groups. In contrast, the two identified studies containing only female subjects (n = 1,754) showed an effect size for cognition of 0.0345 (95% confidence interval, -0.0594 to 0.1285, not significant).

CONCLUSIONS

In the context of a small number of source studies and lack of an all-male group, these results suggest that any association between C-reactive protein and cognitive deficits may be stronger in elderly men than in elderly women.

The role of parasites and pathogens in influencing generalised anxiety and predation-related fear in the mammalian central nervous system

Behavioural and neurophysiological traits and responses associated with anxiety and predation-related fear have been well documented in rodent models. Certain parasites and pathogens which rely on predation for transmission appear able to manipulate these, often innate, traits to increase the likelihood of their life-cycle being completed. This can occur through a range of mechanisms, such as alteration of hormonal and neurotransmitter communication and/or direct interference with the neurons and brain regions that mediate behavioural expression. Whilst some post-infection behavioural changes may reflect 'general sickness' or a pathological by-product of infection, others may have a specific adaptive advantage to the parasite and be indicative of active manipulation of host behaviour. Here we review the key mechanisms by which anxiety and predation-related fears are controlled in mammals, before exploring evidence for how some infectious agents may manipulate these mechanisms. The protozoan Toxoplasma gondii, the causative agent of toxoplasmosis, is focused on as a prime example. Selective pressures appear to have allowed this parasite to evolve strategies to alter the behaviour in its natural intermediate rodent host. Latent infection has also been associated with a range of altered behavioural profiles, from subtle to severe, in other secondary host species including humans. In addition to enhancing our knowledge of the evolution of parasite manipulation in general, to further our understanding of how and when these potential changes to human host behaviour occur, and how we may prevent or manage them, it is imperative to elucidate the associated mechanisms involved.

Inflammatory markers in antipsychotic-naïve patients with nonaffective psychosis and deficit vs. nondeficit features

Newly diagnosed, antipsychotic-naïve patients with nonaffective psychosis appear to have increases in pro-inflammatory cytokines. Patients characterized by primary, enduring negative symptoms (deficit symptoms) differ from patients without such features with regard to course of illness, treatment response, risk factors and metabolic disturbances. We hypothesized that they would also differ on concentrations of the inflammatory markers interleukin-6 (IL6) and C-reactive protein (CRP). Newly diagnosed, antipsychotic-naïve patients with nonaffective psychosis were categorized into deficit (N=20) and nondeficit (N=42) groups, and were matched on age, gender, body mass index, smoking, cortisol level, socioeconomic status, and the severity of psychotic symptoms. Fasting concentrations of IL6 were significantly higher in deficit (mean [S.D.]) (8.0 pg/ml [12.7]) than nondeficit patients (0.3 pg/ml [1.3]). CRP levels were also significantly higher in the deficit patients (0.3 mg/dl [0.4]) vs. (0.2 mg/dl [0.4]), respectively. In contrast, 2-h glucose concentrations (2HG) in a glucose tolerance test were lower in the deficit than the nondeficit group. Our results show a double dissociation with regard to glucose intolerance and inflammation: the deficit group has greater inflammation, but less severe glucose intolerance. These results provide further evidence for the validity of the deficit/nondeficit categorization.

Clinical and biochemical validation of two endophenotypes of schizophrenia defined by levels of polyunsaturated fatty acids in red blood cells

BACKGROUND

Polyunsaturated fatty acids (PUFAs) are bimodally distributed in acute schizophrenia, suggesting two endophenotypes. We intended to characterize these endophenotypes clinically. Our a priori hypothesis was that low PUFA patients have more negative symptoms.

PATIENTS AND METHODS

Patients (aged 18-39) with schizophrenia, schizoaffective or schizophreniform disorders were recruited at hospital admission during an acute episode. The baseline Positive and Negative Syndrome Scale, vital signs and biochemical variables were measured in 97 patients with available RBC PUFA levels. Adjustment for multiple testing was not performed.

RESULTS

The median Negative Subscale score was higher (p=0.04) in the low PUFA (25 points, n=30) than in the high PUFA group (19 points, n=67). Among 95 patients with measurements of serum triglycerides, hypertriglyceridaemia was more prevalent (p=0.009) among low PUFA patients (66%) than high PUFA patients (36%). PUFA modified the effect of antipsychotics on triglycerides (p=0.046). Serum glucose and mean corpuscular haemoglobin were higher (p=0.03, 0.001, respectively) in low PUFA than in high PUFA patients. Low PUFA men were heavier (p=0.04) than high PUFA men.

CONCLUSIONS

During an acute episode of schizophrenia, patients with low RBC PUFA have more negative symptoms and more metabolic and haematological abnormalities than those with high PUFA. This indicates that PUFA levels define two clinically distinct endophenotypes of the disorder.

Cognitive impairment is related to oxidative stress and chemokine levels in first psychotic episodes

INTRODUCTION

This study measures the levels of various markers of oxidative stress and inflammation in blood samples from first-episode psychosis (FEP) patients, and examines the association between these peripheral biomarkers and cognitive performance at 6 months after treatment.

METHODS

Twenty-eight FEP patients and 28 healthy controls (matched by age, sex and educational level) had blood samples taken at admission for assessment of total antioxidant status, superoxide dismutase (SOD), total glutathione (GSH), catalase (CAT), glutathione peroxidase, lipid peroxidation, nitrites and the chemokine monocyte chemoattractant protein-1 (MCP-1). A battery of cognitive tests was also applied to the healthy controls and those FEP patients who were in remission at 6 months after the acute episode.

RESULTS

FEP patients had significantly lower levels of total antioxidant status, catalase and glutathione peroxidase, compared with the healthy controls. Regression analyses found that MCP-1 levels were negatively associated with learning and memory (verbal and working), nitrite levels were negatively associated with executive function, and glutathione levels were positively associated with executive function.

CONCLUSION

Our results suggest an association between certain peripheral markers of oxidative stress and inflammation and specific aspects of cognitive functioning in FEP patients. Further studies on the association between MCP-1 and cognition are warranted.

Adjunct treatments for schizophrenia and bipolar disorder: what to try when you are out of ideas

The pharmacologic treatment of schizophrenia and bipolar disorder leaves much to be desired. Repurposed drugs, which are approved for other medical conditions, represent an underutilized therapeutic resource for patients who have not responded to other drugs. Using experience gained from a decade of repurposed drug studies by the Stanley Medical Research Institute and search of the literature, we have identified nine such drugs for which there is some evidence of efficacy for schizophrenia and/or bipolar disorder. These include: aspirin; celecoxib; estrogen/raloxifene; folate; minocycline; mirtazapine; omega-3 fatty acids; pramipexole; and, pregnenolone. The evidence of efficacy is reviewed for each drug. Because there is little or no financial incentive for pharmaceutical companies to promote such drugs, there is a paucity of definitive trials, and these drugs are less widely known than they deserve to be. Biomarker studies should also be carried out to identify subgroups of patients who do respond to these drugs.

Additive effects of elevated C-reactive protein and exposure to Herpes Simplex Virus type 1 on cognitive impairment in individuals with schizophrenia

OBJECTIVES

We investigated the effect of elevated levels of C-reactive protein (CRP) and exposure to Herpes simplex virus type 1 (HSV-1) on the severity of cognitive impairment in individuals with schizophrenia.

METHODS

We measured the levels of CRP and of antibodies to HSV-1 in serum samples from 588 individuals with schizophrenia by enzyme immunoassay tests. Cognitive functioning was measured with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and psychiatric symptoms with the Positive and Negative Syndrome Scale (PANSS). The effects of HSV1 and CRP on cognitive functioning were analyzed with linear and logistic regression analyses adjusting for demographic and clinical variables.

RESULTS

The individuals with elevated CRP levels and HSV-1 seropositivity had lower RBANS cognitive scores. The strongest effect was found in individuals who had both serological evidence of HSV-1 exposure and elevated levels of CRP. These individuals had odds of 2.35 to have an RBANS Total score<=60 as compared to individuals who were HSV-1 seronegative and who did not have elevated levels of CRP (p=.002). The risks of decreased cognitive functioning associated with HSV-1 exposure and elevated levels of CRP were independent and additive. There was no effect of HSV-1 exposure and CRP levels on the severity of symptoms as measured by the PANSS (all p>.5).

CONCLUSIONS

Elevated levels of CRP and exposure to HSV-1 are associated with the severity of cognitive impairment in schizophrenia. These findings indicate that infection and inflammation may play a major role in the cognitive deficits associated with schizophrenia.

Increase in C-reactive protein and lipids in adolescents with psychiatric disease

Eighteen adolescent patients with severe psychiatric disorders were compared with healthy, eutrophics adolescents for the presence of inflammation and cardiovascular risk factors. We found significant differences in high-sensitivity C-reactive protein, total cholesterol, and triglycerides. Our results show, evidence of an inflammatory status and a deleterious lipid profile, in a very early state of psychiatric disease.

C-reactive protein serum level in drug-free male Egyptian patients with schizophrenia

Despite the growing research interest in the role of immunological markers in schizophrenia, few studies, with conflicting results, have focused on the association between high sensitivity C-reactive protein (hs-CRP) levels and clinical characteristics in schizophrenia. In this cross-sectional case-control study, a sample of 200 antipsychotic-free male Egyptian schizophrenia patients was assessed by the Positive and Negative Syndrome Scale (PANSS) and compared with 200 healthy controls as regards serum hs-CRP level using an immunoturbidimetric method. CRP level for patients (geometric mean=3.3 mg/L) was significantly (P=0.000) higher than that for controls (geometric mean=1.4 mg/L). PANSS scores and patients' data, which significantly correlated with serum hs-CRP level, were entered into a stepwise multiple regression analysis. Results of this analysis showed that PANSS negative symptom score was second only to the waist circumference, with which they explained 54.7 % of the variation in serum hs-CRP. Comparable results were obtained when patients, controls and the relevant confounders were included in one multivariate analysis. We concluded that in Egyptian men, waist circumference and schizophrenia diagnosis are strong predictors of raised CRP level independent of a number of potentially confounding variables. In antipsychotic-free patients, CRP level is higher than in healthy controls and is positively correlated with the severity of the psychopathology as measured by PANSS. This relationship is especially notable in negative, but not positive symptoms.

Anti-inflammatory signaling in schizophrenia

A great deal of interest has been centered upon activated inflammatory processes in schizophrenia and their contribution to disease-relevant brain and behavioral impairment. In contrast, the role of anti-inflammatory signaling has attracted somewhat less attention in this context. The present article focuses on the emerging role of anti-inflammatory signaling in schizophrenia and discusses the potential influence of altered anti-inflammatory activity on progressive inflammatory processes, physical and metabolic functions, and treatment effects related to the use of conventional antipsychotic drugs and immunomodulatory agents in the pharmacotherapy of schizophrenia. By reviewing existing evidence, it appears that enhanced anti-inflammatory activity has many faces in schizophrenia: On the one hand, it may effectively limit potentially harmful inflammatory processes and may contribute to the improvement of psychopathological symptoms, especially when the anti-inflammatory system is boosted at early stages of the disease. On the other hand, enhanced anti-inflammatory activity may render affected individuals more susceptible to distinct physiological abnormalities such as cardiovascular disease, and may further impede the resistance to specific infectious agents. Therefore, an enhancement of anti-inflammatory signaling in schizophrenia might not simply be said to be either advantageous or disadvantageous, but rather should be interpreted and dealt with in a context-dependent manner. Increased awareness of the multiple roles of anti-inflammatory signaling may readily help to reduce additional health burdens in schizophrenia, and at the same time, may provide opportunities to further explore the benefits associated with anti-inflammatory strategies in the symptomatological and/or preventive treatment of this disorder.