Chronic risperidone normalizes elevated pro-inflammatory cytokine and C-reactive protein production in omega-3 fatty acid deficient rats

The effect of risperidone on behavioral reactions and gene expression of pro- and anti-inflammatory cytokines in neuropathic pain model induced by chronic constriction injury of the sciatic nerve in rat

BACKGROUND

Neuropathic pain results from lesions or diseases affecting the somatosensory system. The management of a patient with chronic neuropathic pain remains a challenge several studies report the analgesic effect of serotonin receptor antagonists in different models of experimental pain. The present study was designed to study the effect of systemic administration of risperidone, on behavioral scores of neuropathic pains in chronic constriction (CCI) model in rats.

METHODS

Inducing neuropathic pain with the CCI model which causes heat hyperalgesia, heat, and mechanical allodynia was performed on rats, and then, in two phases, risperidone effect was determined. In the acute phase, risperidone 1, 2, 4 mg was administered for three groups half an hour before behavioral tests on the 7th, 14th, and 21st day after surgery, and in the chronic phase, risperidone 1, 2, and 4 mg was administered for three different groups from the 1st to 14th days after surgery than on 14th-day behavioral scores were performed. For gene expression analysis, samples are taken from spinal cord tissues in lumbar segments.

RESULTS

This study shows chronic administration of risperidone as an antipsychotic drug was effective on heat hyperalgesia and allodynia. However, only the max dosage (4 mg) of risperidone showed meaningful improvement in increasing mechanical allodynia. However, acute administering of risperidone did not show any meaningful changes in behavioral tests on neuropathic pain induced by chronic constriction injury of the sciatic nerve in rats. In addition, gene expression results showed an increase in IL-4 and IL-10 gene expression in the risperidone group compared to the sham group.

CONCLUSION

This study suggests the helpful preventive effects of risperidone in developing and increasing neuropathic pain, but it does not have any instant effect.

Effect of risperidone on serum IL-6 levels in individuals with schizophrenia: a systematic review and meta-analysis

BACKGROUND

Risperidone has been significant correlated with a direct effect of interleukin-6 (IL-6) levels in patients with schizophrenia. This fact allows the opportunity to link the probable immunomodulatory effect of antipsychotic medication. Specially, a proper functioning of IL-6 pathway plays a potential role in the treatment or development of schizophrenia.

OBJECTIVE

Our primary aim was to perform a systematic review and meta-analysis to determine the effect of risperidone on IL-6 levels in individuals with schizophrenia.

METHODS

Studies were identified through a systematic search using PubMed, Scopus, and Web of Science databases. The articles found were subjected to the inclusion and exclusion criteria; then, the mean and standardised differences were extracted to calculate the standardised mean differences using the CMA software.

RESULTS

IL-6 levels in individuals with schizophrenia were compared before and after receiving risperidone as treatment. Increased levels of IL-6 levels were observed in individuals with schizophrenia who received risperidone (point estimate 0.249, lower limit 0.042, upper limit 0.455, p-value 0.018). In the Asian population sub-analysis, no statistically significant differences were observed (point estimate 0.103, lower limit -0.187, upper limit 0.215, p value 0.890). When we compared individuals with schizophrenia to the control groups, a significant increase of IL-6 levels was observed in the group with schizophrenia (point estimate 0.248, lower limit 0.024, upper limit 0.472, p-value 0.30).

CONCLUSIONS

Risperidone appears to play an important role in IL-6 levels in schizophrenia. Potential implications of increased IL-6 levels in people with schizophrenia should be considered in future studies.KEY POINTSIncreased levels of IL-6 levels were observed in individuals with schizophrenia who received risperidone.Risperidone appears to play an important role in IL-6 levels in schizophrenia.This study could serve for future research focussed on IL-6.

A 16-week randomized placebo-controlled trial investigating the effects of omega-3 polyunsaturated fatty acid treatment on white matter microstructure in recent-onset psychosis patients concurrently treated with risperidone

We examined the impact of treatment with fish oil (FO), a rich source of omega-3 polyunsaturated fatty acids (n-3 PUFA), on white matter in 37 recent-onset psychosis patients receiving risperidone in a double-blind placebo-controlled randomized clinical trial. Patients were scanned at baseline and randomly assigned to receive 16-weeks of treatment with risperidone + FO or risperidone + placebo. Eighteen patients received follow-up MRIs (FO, n = 10/Placebo, n = 8). Erythrocyte levels of n-3 PUFAs eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and docosapentaenoic acid (DPA) were obtained at both time points. We employed Free Water Imaging metrics representing the extracellular free water fraction (FW) and fractional anisotropy of the tissue (FA-t). Analyses were conducted using Tract-Based-Spatial-Statistics and nonparametric permutation-based tests with family-wise error correction. There were significant positive correlations of FA-t with DHA and DPA among all patients at baseline. Patients treated with risperidone + placebo demonstrated reductions in FA-t and increases in FW, whereas patients treated with risperidone + FO exhibited no significant changes in FW and FA-t reductions were largely attenuated. The correlations of DPA and DHA with baseline FA-t support the hypothesis that n-3 PUFA intake or biosynthesis are associated with white matter abnormalities in psychosis. Adjuvant FO treatment may partially mitigate against white matter alterations observed in recent-onset psychosis patients following risperidone treatment.

Immunomodulatory Effects of Antipsychotic Drugs in Whole Blood Cell Cultures from Healthy Subjects

Objective:

We aimed to evaluate the effects of various antipsychotics on the in vitro production of C-reactive protein (CRP) in whole blood cell cultures from healthy volunteers. The evaluation was performed using haloperidol, quetiapine, clozapine, amisulpride, and chlorpromazine.

Methods:

Antipsychotic agents were added to the participants' whole blood samples, and the resulting CRP levels were measured. For each agent, three different concentrations were tested: the therapeutic concentration, one-tenth the therapeutic concentration, and ten times the therapeutic concentration. The differences in CRP concentrations before and after drug administration were investigated.

Results:

The Friedman test showed that haloperidol, amisulpride, and chlorpromazine significantly increased CRP levels in the blood culture samples; however, clozapine and quetiapine did not increase CRP levels. In the case of chlorpromazine, elevated CRP levels were noted at all concentrations tested.

Conclusion:

Our study suggests that some antipsychotics elevate CRP levels in vitro. These results agree with previous studies showing that antipsychotics have immunomodulatory effects. Future research will clarify our findings and our understanding of antipsychotic drugs and their impact on immune regulation.

Immunoendocrine Peripheral Effects Induced by Atypical Antipsychotics

Atypical antipsychotics (AAP) or second-generation antipsychotics are the clinical option for schizophrenia treatment during acute psychoses, but they are also indicated for maintenance during lifetime, even though they are being used for other psychiatric conditions in clinical practice such as affective disorders and autism spectrum disorder, among others. These drugs are differentiated from typical antipsychotics based on their clinical profile and are a better choice because they cause fewer side effects regarding extrapyramidal symptoms (EPS). Even though they provide clear therapeutic benefits, AAP induce peripheral effects that trigger phenotypic, functional, and systemic changes outside the Central Nervous System (CNS). Metabolic disease is frequently associated with AAP and significantly impacts the patient's quality of life. However, other peripheral changes of clinical relevance are present during AAP treatment, such as alterations in the immune and endocrine systems as well as the intestinal microbiome. These less studied alterations also have a significant impact in the patient's health status. This manuscript aims to revise the peripheral immunological, endocrine, and intestinal microbiome changes induced by AAP consumption recommended in the clinical guidelines for schizophrenia and other psychiatric disorders.

Risperidone Ameliorates Prefrontal Cortex Neural Atrophy and Oxidative/Nitrosative Stress in Brain and Peripheral Blood of Rats with Neonatal Ventral Hippocampus Lesion

Reduction of the dendritic arbor length and the lack of dendritic spines in the pyramidal cells of the prefrontal cortex (PFC) are prevalent pathological features in schizophrenia (SZ). Neonatal ventral hippocampus lesion (NVHL) in male rats reproduces these neuronal characteristics and here we describe how this is a consequence of BDNF/TrkB pathway disruption. Moreover, COX-2 proinflammatory state, as well as Nrf-2 antioxidant impairment, triggers oxidative/nitrosative stress, which also contributes to dendritic spine impairments in the PFC. Interestingly, oxidative/nitrosative stress was also detected in the periphery of NVHL animals. Furthermore, risperidone treatment had a neurotrophic effect on the PFC and antioxidant effects on the brain and periphery of NVHL animals; these cellular effects were related to behavioral improvement. Our data highlight the link between brain development and immune response, as well as several other factors to understand mechanisms related to the pathophysiology of SZ.SIGNIFICANCE STATEMENT Prefrontal cortex dysfunction in schizophrenia can be a consequence of morphological abnormalities and oxidative/nitrosative stress, among others. Here, we detailed how impaired plasticity-related pathways and oxidative/nitrosative stress are part of the dendritic spine pathology and their modulation by atypical antipsychotic risperidone treatment in rats with neonatal ventral hippocampus lesion. Moreover, we found that animals with neonatal ventral hippocampus lesion had oxidative/nitrosative stress in the brain as well as in the peripheral blood, an important issue for the translational approaches of this model. Then, risperidone restored plasticity and reduced oxidative/nitrosative stress of prefrontal cortex pyramidal cells, and ultimately improved the behavior of lesioned animals. Moreover, risperidone had differential effects than the brain on peripheral blood oxidative/nitrosative stress.

From Infection to the Microbiome: An Evolving Role of Microbes in Schizophrenia

The study of microorganisms such as bacteria, viruses, archaea, fungi, and protozoa in the context of psychiatric disorders may be surprising to some. This intersection of disciplines, however, has a rich history and is currently revitalized by newfound functions of the microbiome and the gut-brain axis in human diseases. Schizophrenia, in particular, fits this model as a disorder with gene and environmental roots that may be anchored in the immune system. In this context, the combination of a precisely timed pathogen exposure in a person with genetically encoded altered immunity may have especially destructive consequences for the central nervous system (CNS). Furthermore, significant components of immunity, such as the development of the immune response and the concept of immune tolerance, are largely dictated by the commensal residents of the microbiome. When this community of microbes is imbalanced, perhaps as the result of a pathogen invasion, stress, or immune gene deficiency, a pathological cycle of localized inflammation, endothelial barrier compromise, translocation of gut-derived products, and systemic inflammation may ensue. If these pathologies enable access of gut and microbial metabolites and immune molecules to the CNS across the blood-brain barrier (BBB), and studies of the gut-brain axis support this hypothesis, a worsening of cognitive deficits and psychiatric symptoms is predicted to occur in susceptible individuals with schizophrenia. In this chapter, we review the role of microbes in various stages of this model and how these organisms may contribute to documented phenotypes of schizophrenia. An increased understanding of the role of pathogens and the microbiome in psychiatric disorders will better guide the development of microbial and immune-based therapeutics for disease prevention and treatment.

The association between low-grade inflammation and the clinical features of bipolar disorder in Han Chinese population

Variety of evidence suggests that low-grade inflammation may be involved in the pathophysiology of bipolar disorder (BD). However, the conclusion regarding the relationship between inflammation and BD has been inconsistent. In this study, we aimed to survey the prevalence of low-grade inflammation in a large Han Chinese population with BD and assess its impact on the clinical features of BD. 430 eligible cases were drawn from patients who were admitted or had ever been admitted for BD to the inpatient service of the psychiatric department of the Third Hospital of Sun Yat-sen University. Subjects with current active physical diseases or white blood count (WBC) >19.0 × 10⁹/L (2 times the upper reference) were excluded. Serum C-reactive protein (CRP) levels and WBC were measured with fast blood sample. Low-grade inflammation was defined as CRP>3 mg/L or WBC > 9.5 × 10⁹/L(the upper reference). Clinical features of BD were collected through semi-structural interview conducted by trained interviewers with background of psychiatric education. If defined as CRP>3 mg/L, the prevalence of low-grade inflammation among BD was 10.1% (41/404), it was positively associated with BMI (p = 0.012), comorbidity of glycolipid metabolic diseases(p = 0.018). After adjusting for BMI, it was found to be positively related to recent suicide attempt (p = 0.03), initiation with (hypo)manic episode(p = 0.047), leaden paralysis (p = 0.037) and family history of mental disorders(p = 0.012), while the association between comorbidity of glycolipid metabolic diseases and low-grade inflammation disappeared (p = 0.330). If defined as WBC > 9.5 × 10⁹/L, the prevalence of low-grade inflammation was 8.1% (33/409), it was positively associated with psychotic features (p = 0.011) and adverse life events before the onset of illness(p < 0.001), but was not significantly influenced by BMI (p = 0.077). A much lower prevalence of low-grade inflammation in BD is found among Han Chinese population than among western population. Low-grade inflammation of different definition impacts differentially on the clinical features of BD.

Access to the CNS: Biomarker Strategies for Dopaminergic Treatments

Despite substantial research carried out over the last decades, it remains difficult to understand the wide range of pharmacological effects of dopaminergic agents. The dopaminergic system is involved in several neurological disorders, such as Parkinson's disease and schizophrenia. This complex system features multiple pathways implicated in emotion and cognition, psychomotor functions and endocrine control through activation of G protein-coupled dopamine receptors. This review focuses on the system-wide effects of dopaminergic agents on the multiple biochemical and endocrine pathways, in particular the biomarkers (i.e., indicators of a pharmacological process) that reflect these effects. Dopaminergic treatments developed over the last decades were found to be associated with numerous biochemical pathways in the brain, including the norepinephrine and the kynurenine pathway. Additionally, they have shown to affect peripheral systems, for example the hypothalamus-pituitary-adrenal (HPA) axis. Dopaminergic agents thus have a complex and broad pharmacological profile, rendering drug development challenging. Considering the complex system-wide pharmacological profile of dopaminergic agents, this review underlines the needs for systems pharmacology studies that include: i) proteomics and metabolomics analysis; ii) longitudinal data evaluation and mathematical modeling; iii) pharmacokinetics-based interpretation of drug effects; iv) simultaneous biomarker evaluation in the brain, the cerebrospinal fluid (CSF) and plasma; and v) specific attention to condition-dependent (e.g., disease) pharmacology. Such approach is considered essential to increase our understanding of central nervous system (CNS) drug effects and substantially improve CNS drug development.

Different Immune Signature in Youths Experiencing Antipsychotic-Induced Weight Gain Compared to Untreated Obese Patients

OBJECTIVES

To assess cytokine and chemokine levels in youth experiencing antipsychotic-induced weight gain (AIWG) compared to obese patients, hypothesizing a different "immune signature" between the two kinds of obesity.

METHODS

We compared a group of youth experiencing AIWG (N 19, mean age 159 months, mean body mass index [BMI] z-score 1.81) and an age-, gender-, and BMI-matched group of untreated obese patients (N 19, mean age 147 months, mean BMI z-score 2) for a wide range of cytokines and chemokines by using a multiplex ELISA test.

RESULTS

Platelet-derived growth factor (PDGF), interleukin (IL)1-β, IL4, IL8, IL9, IL12, IL 17, eotaxin, FGF, GMCSF, IP10, MIP1b, and vascular-endothelial growth factor (VEGF) were significantly lower in the AIWG group, whereas IL13 and RANTES were significantly higher. Controlling for age, sex, and BMI, PDGF, IL4, IL8, IL13, IL17, eotaxin, fibroblast growth factor (FGF), granulocyte-macrophage colony-stimulating factor (GMCSF), IP10, MIP1b, and VEGF remain significantly different.

CONCLUSION

A clearly different pattern of cytokines distinguishes the two kinds of obesity, suggesting a different immune signature. Interestingly, most of the cytokines and chemokines bearing proinflammatory effects resulted decreased in the AIWG group, whereas IL-13, which holds an immune-modulatory effect, resulted increased.

Peripheral blood gene expression of acute phase proteins in people with first episode psychosis

BACKGROUND

There is a growing interest in the association between schizophrenia and the activation of inflammatory system with signs of acute phase (AP) response. Majority of such studies had focused on C-reactive protein (CRP). The aims of the present study were (i) to examine the gene expression profiles of other acute phase proteins (APP), namely haptoglobin (HP), alpha-1 antitrypsin (A1T), and alpha-2 macroglobulin (A2M) in patients with first episode psychosis (FEP) over a period of three months and (ii) to explore the association between APP levels and severity of symptoms.

METHODS

In this study, HP, A1T and A2M gene expression levels from whole blood were measured at recruitment, 1- and 3-month follow-up visits using quantitative PCR (qPCR) in 43 patients with FEP and in 57 healthy controls. Diagnoses was ascertained on the Structured Clinical Interview for DSM-IV-TR. Severity of symptoms in patients was assessed on the Positive and Negative Syndrome Scale (PANSS) and a previously validated 5-factor PANSS structure was applied in the subsequent analyses.

RESULTS

The FEP sample comprised of 28 (65.1%) individuals with schizophrenia, 12 (27.9%) with schizophreniform disorder and 3 (7%) with schizoaffective disorder. HP gene expression level was noted to be significantly higher in patients than controls at all three time points: recruitment (P=0.049), 1-month follow up (P=0.002) and 3-month follow up (P=0.005). PANSS positive, depression, and excitement symptom factors showed significant associations with HP (P=0.002), A1T (P=0.016) and A2M (P=0.034), respectively. These findings remained significant after controlling for age, gender, smoking status and accumulated chlorpromazine dosage.

CONCLUSION

The current study provides information on HP, A1T and A2M gene expression profiles in FEP patients and their associations with psychopathology. This provides support for the hypothesis that inflammation is related to schizophrenia and further encourages studies on immune-inflammatory markers to understand the relationship between inflammation and schizophrenia.

Autoimmune diseases, gastrointestinal disorders and the microbiome in schizophrenia: more than a gut feeling

Autoimmunity, gastrointestinal (GI) disorders and schizophrenia have been associated with one another for a long time. This paper reviews these connections and provides a context by which multiple risk factors for schizophrenia may be related. Epidemiological studies strongly link schizophrenia with autoimmune disorders including enteropathic celiac disease. Exposure to wheat gluten and bovine milk casein also contribute to non-celiac food sensitivities in susceptible individuals. Co-morbid GI inflammation accompanies humoral immunity to food antigens, occurs early during the course of schizophrenia and appears to be independent from antipsychotic-generated motility effects. This inflammation impacts endothelial barrier permeability and can precipitate translocation of gut bacteria into systemic circulation. Infection by the neurotropic gut pathogen, Toxoplasma gondii, will elicit an inflammatory GI environment. Such processes trigger innate immunity, including activation of complement C1q, which also functions at synapses in the brain. The emerging field of microbiome research lies at the center of these interactions with evidence that the abundance and diversity of resident gut microbiota contribute to digestion, inflammation, gut permeability and behavior. Dietary modifications of core bacterial compositions may explain inefficient gluten digestion and how immigrant status in certain situations is a risk factor for schizophrenia. Gut microbiome research in schizophrenia is in its infancy, but data in related fields suggest disease-associated altered phylogenetic compositions. In summary, this review surveys associative and experimental data linking autoimmunity, GI activity and schizophrenia, and proposes that understanding of disrupted biological pathways outside of the brain can lend valuable information regarding pathogeneses of complex, polygenic brain disorders.

C-reactive protein is increased in schizophrenia but is not altered by antipsychotics: meta-analysis and implications

The inflammatory hypothesis of schizophrenia (SZ) posits that inflammatory processes and neural-immune interactions are involved in its pathogenesis, and may underpin some of its neurobiological correlates. SZ is the psychiatric disorder causing the most severe burden of illness, not just owing to its psychiatric impairment, but also owing to its significant medical comorbidity. C-reactive protein (CRP) is a commonly used biomarker of systemic inflammation worldwide. There are some conflicting results regarding the behaviour of CRP in SZ. The aims of this study were to verify whether peripheral CRP levels are indeed increased in SZ, whether different classes of antipsychotics divergently modulate CRP levels and whether its levels are correlated with positive and negative symptomatology. With that in mind, we performed a meta-analysis of all cross-sectional studies of serum and plasma CRP levels in SZ compared to healthy subjects. In addition, we evaluated longitudinal studies on CRP levels before and after antipsychotic use. Our meta-analyses of CRP in SZ included a total of 26 cross-sectional or longitudinal studies comprising 85 000 participants. CRP levels were moderately increased in persons with SZ regardless of the use of antipsychotics and did not change between the first episode of psychosis and with progression of SZ (g=0.66, 95% confidence interval (95% CI) 0.43 to 0.88, P<0.001, 24 between-group comparisons, n=82 962). The extent of the increase in peripheral CRP levels paralleled the increase in severity of positive symptoms, but was unrelated to the severity of negative symptoms. CRP levels were also aligned with an increased body mass index. Conversely, higher age correlated with a smaller difference in CRP levels between persons with SZ and controls. Furthermore, CRP levels did not increase after initiation of antipsychotic medication notwithstanding whether these were typical or atypical antipsychotics (g=0.01, 95% CI -0.20 to 0.22, P=0.803, 8 within-group comparisons, n=713). In summary, our study provides further evidence of the inflammatory hypothesis of SZ. Whether there is a causal relationship between higher CRP levels and the development of SZ and aggravation of psychotic symptoms, or whether they are solely a marker of systemic low-grade inflammation in SZ, remains to be clarified.

First-episode bipolar disorder is associated with erythrocyte membrane docosahexaenoic acid deficits: Dissociation from clinical response to lithium or quetiapine

Deficits in long-chain omega-3 (LCn-3) fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may be associated with the pathophysiology of bipolar disorder. However, LCn-3 fatty acid status at the initial onset of mania and its association with treatment response are not known. Erythrocyte membrane fatty acid composition was determined in first-episode bipolar manic or mixed (n=40) and healthy (n=40) subjects. Mood symptom ratings were obtained with the Young Mania Rating Scale (YMRS) and the Hamilton Depression Rating Scale (HDRS). Erythrocyte fatty acid composition and clinical ratings were also determined within a sub-group of bipolar subjects following 8-week (n=19) or 52-week (n=11) open-label treatment with lithium or quetiapine. At baseline bipolar subjects exhibited significantly lower erythrocyte docosahexaenoic acid (DHA, 22:6n-3) composition compared with healthy subjects (-23%, p<0.0001). EPA (20:5n-3) and docosapentanoic acid (22:5n-3), and LCn-6 fatty acids including arachidonic acid were not different. Following 8- or 52-week treatment with lithium or quetiapine, YMRS and HDRS total scores decreased significantly whereas erythrocyte fatty acids including DHA did not change. These data indicate that selective erythrocyte DHA deficits coincide with the initial onset of manic symptoms, and reductions in mood symptoms following treatment are not mediated by changes in fatty acid status.

Elevated immune-inflammatory signaling in mood disorders: a new therapeutic target?

Converging translational evidence has implicated elevated immune-inflammatory signaling activity in the pathoetiology of mood disorders, including major depressive disorder and bipolar disorder. This is supported in part by cross-sectional evidence for increased levels of proinflammatory eicosanoids, cytokines and acute-phase proteins during mood episodes, and prospective longitudinal evidence for the emergence of mood symptoms in response to chronic immune-inflammatory activation. In addition, mood-stabilizer and atypical antipsychotic medications downregulate initial components of the immune-inflammatory signaling pathway, and adjunctive treatment with anti-inflammatory agents augment the therapeutic efficacy of antidepressant, mood stabilizer and atypical antipsychotic medications. Potential pathogenic mechanisms linked with elevated immune-inflammatory signaling include perturbations in central serotonin neurotransmission and progressive white matter pathology. Both heritable genetic factors and environmental factors including dietary fatty-acid composition may act in concert to sustain elevated immune-inflammatory signaling. Collectively, these data suggest that elevated immune-inflammatory signaling is a mechanism that is relevant to the pathoetiology of mood disorders, and may therefore represent a new therapeutic target for the development of more effective treatments.

Risperidone normalizes increased inflammatory parameters and restores anti-inflammatory pathways in a model of neuroinflammation

Inflammation, caused by both external and endogenous factors, has been implicated as a main pathophysiological feature of chronic mental illnesses, including schizophrenia. An increase in pro-inflammatory cytokines has been described both in experimental models and in schizophrenia patients. However, not much is known about the effects that antipsychotic drugs have on intra- and intercellular mechanisms controlling inflammation. The aim of the present study was to investigate the possible anti-inflammatory effect of a standard schizophrenia treatment not only at the level of soluble mediators, but also at intra- and intercellular inflammatory pathways. The present study was conducted in a model of mild neuroinflammation using a lipopolysaccharide (LPS) challenge that was not an endotoxaemic dose (0.5 mg/kg i.p.) in young adult rats.

MAIN RESULTS

single doses of risperidone (0.3-3.0 mg/kg i.p.) prevented increased inflammatory parameters induced by LPS in brain cortex [expression of inflammatory cytokines, interleukin (IL)-1β and tumour necrosis factor (TNF)-α, activity of the inducible inflammatory enzymes nitric oxide synthase and cyclooxygenase, p38 mitogen-activated protein kinase (MAPK) and inflammatory nuclear transcription factor κB] and restored anti-inflammatory pathways decreased by LPS challenge (deoxyprostaglandins and peroxisome proliferator activated receptor γ). This is the first study demonstrating that risperidone elicits a preventive effect on the anti-inflammatory arm of the homeostatic mechanism controlling inflammation in a model of mild encephalitis in rats. Our findings suggest a possible protective effect of risperidone on brain cells.

Gastrointestinal inflammation and associated immune activation in schizophrenia

Immune factors are implicated in normal brain development and in brain disorder pathogenesis. Pathogen infection and food antigen penetration across gastrointestinal barriers are means by which environmental factors might affect immune-related neurodevelopment. Here, we test if gastrointestinal inflammation is associated with schizophrenia and therefore, might contribute to bloodstream entry of potentially neurotropic milk and gluten exorphins and/or immune activation by food antigens. IgG antibodies to Saccharomyces cerevisiae (ASCA, a marker of intestinal inflammation), bovine milk casein, wheat-derived gluten, and 6 infectious agents were assayed. Cohort 1 included 193 with non-recent onset schizophrenia, 67 with recent onset schizophrenia and 207 non-psychiatric controls. Cohort 2 included 103 with first episode schizophrenia, 40 of whom were antipsychotic-naïve. ASCA markers were significantly elevated and correlated with food antigen antibodies in recent onset and non-recent onset schizophrenia compared to controls (p≤0.00001-0.004) and in unmedicated individuals with first episode schizophrenia compared to those receiving antipsychotics (p≤0.05-0.01). Elevated ASCA levels were especially evident in non-recent onset females (p≤0.009), recent onset males (p≤0.01) and in antipsychotic-naïve males (p≤0.03). Anti-food antigen antibodies were correlated to antibodies against Toxoplasma gondii, an intestinally-infectious pathogen, particularly in males with recent onset schizophrenia (p≤0.002). In conclusion, gastrointestinal inflammation is a relevant pathology in schizophrenia, appears to occur in the absence of but may be modified by antipsychotics, and may link food antigen sensitivity and microbial infection as sources of immune activation in mental illness.

The use of omega-3 fatty acids in mental illness

PURPOSE

This article will summarize the current evidence on the effects of omega-3 fatty acids on prevention and treatment of mental illness.

BACKGROUND

Omega-3 fatty acids are involved in many physiologic processes. Since they cannot be made de novo in the body, they are considered essential nutrients. As the Western diet evolved, dietary intake of fatty acids has shifted to increased omega-6 fatty acids and decreased omega-3 fatty acids intake. These changes have been correlated with numerous differences in prevalence and course of mental illnesses.

METHODS

A MEDLINE search from 1966 to December 2010 was completed to identify studies comparing changes in symptoms, functioning, other outcomes, and/or side effects in patients treated with omega-3 fatty acids for mental illness. The studies were reviewed and reported by specific psychiatric disorder studied.

CONCLUSIONS

Omega-3 fatty acids play a role in many biologic functions. Epidemiologic data implicate omega-3 fatty acid deficiencies in many mental illnesses. Data are most robust for omega-3 fatty acids' role in affective disorders. However, data are conflicting, negative, or absent for most mental illnesses.