Schizophrenia: metabolic aspects of aetiology, diagnosis and future treatment strategies

Risk Factors for Natural Cause Mortality in Schizophrenia

Importance

Schizophrenia is associated with premature mortality from mostly natural causes. Decreased cognitive functioning has been identified as a determinant of mortality in the general population. However, there have been few prospective studies of this issue in persons with schizophrenia.

Objective

To examine whether lower cognitive functioning is a risk factor for natural cause mortality in schizophrenia.

Design, Setting, and Participants

This prospective cohort study included persons with schizophrenia or schizoaffective disorder enrolled between February 1, 1999, and December 31, 2022, at a nonprofit psychiatric system in Baltimore, Maryland. Participants were evaluated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and other clinical measures.

Exposure

Natural cause mortality.

Main Outcomes and Measures

Associations of cognitive function, obesity, tobacco smoking, and medical conditions with natural cause mortality were evaluated using Cox proportional hazards regression models.

Results

Of the 844 participants enrolled (mean [SD] age, 39.6 [12.1] years; 533 male [63.2%]), 158 (18.7%) died of natural causes during a median follow-up of 14.4 years (range, 7.0 days to 23.9 years). The most significant factor associated with mortality was lower cognitive functioning as measured by the RBANS (Cox coefficient, -0.04; 95% CI, -0.05 to -0.03; z = -5.72; adjusted P < .001). Additional factors independently associated with mortality included the diagnosis of an autoimmune disorder (hazard ratio [HR], 2.86; 95% CI, 1.83-4.47; z = 4.62; adjusted P < .001), tobacco smoking (HR, 2.26; 95% CI, 1.55-3.30; z = 4.23; adjusted P < .001), diagnosis of chronic obstructive pulmonary disease (HR, 3.31; 95% CI, 1.69-6.49; z = 3.48; adjusted P = .006), body mass index as a continuous variable (HR, 1.06; 95% CI, 1.02-1.09; z = 3.30; adjusted P = .01), diagnosis of a cardiac rhythm disorder (HR, 2.56; 95% CI, 1.40-4.69; z = 3.06; adjusted P = .02), and being divorced or separated (HR, 1.80; 95% CI, 1.22-2.65; z = 2.97; adjusted P = .02). An RBANS score below the 50th percentile displayed a joint association with being a smoker, having an elevated body mass index, and having a diagnosis of an autoimmune or a cardiac rhythm disorder.

Conclusions and Relevance

In this prospective cohort study, lower cognitive functioning was a risk factor for natural cause mortality in schizophrenia. Efforts should be directed at methods to improve cognitive functioning, particularly among individuals with additional risk factors.

A Global, Regional, and National Burden and Quality of Care Index for Schizophrenia: Global Burden of Disease Systematic Analysis 1990-2019

BACKGROUND AND HYPOTHESIS

Schizophrenia is a mental disorder usually presented in adulthood that affects roughly 0.3 percent of the population. The disease contributes to more than 13 million years lived with disability the global burden of disease. The current study aimed to provide new insights into the quality of care in Schizophrenia via the implementation of the newly introduced quality of care index (QCI) into the existing data.

STUDY DESIGN

The data from the global burden of disease database was used for schizophrenia. Two secondary indices were calculated from the available indices and used in a principal component analysis to develop a proxy of QCI for each country. The QCI was then compared between different sociodemographic index (SDI) and ages. To assess the disparity in QCI between the sexes, the gender disparity ratio (GDR) was also calculated and analyzed in different ages and SDIs.

STUDY RESULTS

The global QCI proxy score has improved between 1990 and 2019 by roughly 13.5%. Concerning the gender disparity, along with a rise in overall GDR the number of countries having a GDR score of around one has decreased which indicates an increase in gender disparity regarding quality of care of schizophrenia. Bhutan and Singapore had 2 of the highest QCIs in 2019 while also showing GDR scores close to one.

CONCLUSIONS

While the overall conditions in the quality of care have improved, significant disparities and differences still exist between different countries, genders, and ages in the quality of care regarding schizophrenia.

Nano Lipid Carriers as a Promising Drug Delivery Carrier for Neurodegenerative Disorders - An Overview of Recent Advances

The last few decades have seen a rise in the number of deaths caused by neurological disorders. The blood-brain barrier (BBB), which is very complex and has multiple mechanisms, makes drug delivery to the brain challenging for many scientists. Lipid nanoparticles (LNPs) such as nanoemulsions, solid-lipid nanoparticles, liposomes, and nano lipid carriers (NLCs) exhibit enhanced bioavailability and flexibility among these nanocarriers. NLCs are found to be very effective. In the last few decades, they have been a center of attraction for controlled drug delivery. According to the current global status of specific neurological disorders, out of all LNPs, NLC significantly reduces the cross-permeability of drugs through the BBB due to their peculiar properties. They offer a host of advantages over other carriers because of their biocompatibility, safety, non-toxicity, non-irritating behavior, stability, high encapsulation efficiency, high drug loading, high drug targeting, control of drug release, and ease in manufacturing. The biocompatible lipid matrix is ideally suited as a drug carrier system due to the nano-size range. For certain neurological conditions such as Parkinsonism, Alzheimer's, Epilepsy, Multiple sclerosis, and Brain cancer, we examined recent advances in NLCs to improve brain targeting of bioactive with special attention to formulation aspects and pharmacokinetic characteristics. This article also provides a brief overview of a critical approach for brain targeting, i.e., direct nose-to-brain drug delivery and some recent patents published on NLC".

Association of clinical parameters and polygenic risk scores for body mass index, schizophrenia, and diabetes with antipsychotic-induced weight gain

Antipsychotic-induced weight gain (AIWG) is a common adverse event in schizophrenia. Genome-wide association studies (GWAS) and polygenic risk scores (PRS) for other diseases or traits are recent approaches to disentangling the genetic architecture of AIWG. 200 patients with schizophrenia treated monotherapeutically with antipsychotics were included in this study. A multiple linear regression analysis with ten-fold crossvalidation was performed to predict the percentage weight change after five weeks of treatment. Independent variables were sex, age, body mass index (BMI) at baseline, medication-associated risk, and PRSs (BMI, schizophrenia, diabetes, and metabolic syndrome). An explorative GWAS analysis was performed on the same subjects and traits. PRSs for BMI (β = 3.78; p = 0.0041), schizophrenia (β = 5.38; p = 0.021) and diabetes type 2 (β = 13.4; p = 0.046) were significantly associated with AIWG. Other significant factors were sex, baseline BMI and medication. Compared to the model without genetic factors, the addition of PRSs for BMI, schizophrenia, and diabetes type 2 increased the goodness of fit by 6.5 %. The GWAS identified the association of three variants (rs10668573, rs10249381 and rs1988834) with AIWG at a genome-wide level of p < 1 · 10-6. Using PRS for schizophrenia, BMI, and diabetes type 2 increased the explained variation of predicted weight gain, compared to a model without PRSs. For more precise results, PRSs derived from other traits (ideally AIWG) should be investigated. Potential risk variants identified in our GWAS need to be further investigated and replicated in independent samples.

Characterizing the Shared Genetic Underpinnings of Schizophrenia and Cardiovascular Disease Risk Factors

OBJECTIVE

Schizophrenia is associated with increased risk of cardiovascular disease (CVD), although there is variation in risk among individuals. There are indications of shared genetic etiology between schizophrenia and CVD, but the nature of the overlap remains unclear. The aim of this study was to fill this gap in knowledge.

METHODS

Overlapping genetic architectures between schizophrenia and CVD risk factors were assessed by analyzing recent genome-wide association study (GWAS) results. The bivariate causal mixture model (MiXeR) was applied to estimate the number of shared variants and the conjunctional false discovery rate (conjFDR) approach was used to pinpoint specific shared loci.

RESULTS

Extensive genetic overlap was found between schizophrenia and CVD risk factors, particularly smoking initiation (N=8.6K variants) and body mass index (BMI) (N=8.1K variants). Several specific shared loci were detected between schizophrenia and BMI (N=304), waist-to-hip ratio (N=193), smoking initiation (N=293), systolic (N=294) and diastolic (N=259) blood pressure, type 2 diabetes (N=147), lipids (N=471), and coronary artery disease (N=35). The schizophrenia risk loci shared with smoking initiation had mainly concordant effect directions, and the risk loci shared with BMI had mainly opposite effect directions. The overlapping loci with lipids, blood pressure, waist-to-hip ratio, type 2 diabetes, and coronary artery disease had mixed effect directions. Functional analyses implicated mapped genes that are expressed in brain tissue and immune cells.

CONCLUSIONS

These findings indicate a genetic propensity to smoking and a reduced genetic risk of obesity among individuals with schizophrenia. The bidirectional effects of the shared loci with the other CVD risk factors may imply differences in genetic liability to CVD across schizophrenia subgroups, possibly underlying the variation in CVD comorbidity.

Molecular Mechanism Biomarkers Predict Diagnosis in Schizophrenia and Schizoaffective Psychosis, with Implications for Treatment

Diagnostic uncertainty and relapse rates in schizophrenia and schizoaffective disorder are relatively high, indicating the potential involvement of other pathological mechanisms that could serve as diagnostic indicators to be targeted for adjunctive treatment. This study aimed to seek objective evidence of methylenetetrahydrofolate reductase MTHFR C677T genotype-related bio markers in blood and urine. Vitamin and mineral cofactors related to methylation and indolamine-catecholamine metabolism were investigated. Biomarker status for 67 symptomatically well-defined cases and 67 asymptomatic control participants was determined using receiver operating characteristics, Spearman's correlation, and logistic regression. The 5.2%-prevalent MTHFR 677 TT genotype demonstrated a 100% sensitive and specific case-predictive biomarkers of increased riboflavin (vitamin B2) excretion. This was accompanied by low plasma zinc and indicators of a shift from low methylation to high methylation state. The 48.5% prevalent MTHFR 677 CC genotype model demonstrated a low-methylation phenotype with 93% sensitivity and 92% specificity and a negative predictive value of 100%. This model related to lower vitamin cofactors, high histamine, and HPLC urine indicators of lower vitamin B2 and restricted indole-catecholamine metabolism. The 46.3%-prevalent CT genotype achieved high predictive strength for a mixed methylation phenotype. Determination of MTHFR C677T genotype dependent functional biomarker phenotypes can advance diagnostic certainty and inform therapeutic intervention.

Cytokine alterations in CSF and serum samples of patients with a first episode of schizophrenia: results and methodological considerations

We determined cytokine levels in paired serum/CSF samples from first-episode schizophrenia (FES) participants (n = 20) and controls (n = 21) using a 13-plex immunoassay. Applying strictly-determined detection limits, 12 cytokines were found in serum and two in CSF. Higher serum MCP-1 levels (p = 0.007) were present in FES versus controls, which correlated with serum IgG (R = - 0.750; p = 0.013). Finally, IL-18 levels correlated with body weight in FES (R = 0.691; p = 0.041). This study demonstrates potential limitations in the sensitivity of multiplex cytokine assays for CSF studies in mental disorders and suggests that some published studies in this area should be re-evaluated.

Diagnostic model development for schizophrenia based on peripheral blood mononuclear cell subtype-specific expression of metabolic markers

A significant proportion of the personal and economic burden of schizophrenia can be attributed to the late diagnosis or misdiagnosis of the disorder. A novel, objective diagnostic approaches could facilitate the early detection and treatment of schizophrenia and improve patient outcomes. In the present study, we aimed to identify robust schizophrenia-specific blood biomarkers, with the goal of developing an accurate diagnostic model. The levels of selected serum and peripheral blood mononuclear cell (PBMC) markers relevant to metabolic and immune function were measured in healthy controls (n = 26) and recent-onset schizophrenia patients (n = 36) using multiplexed immunoassays and flow cytometry. Analysis of covariance revealed significant upregulation of insulin receptor (IR) and fatty acid translocase (CD36) levels in T helper cells (F = 10.75, P = 0.002, Q = 0.024 and F = 21.58, P = 2.8 × 10^-5, Q = 0.0004, respectively), as well as downregulation of glucose transporter 1 (GLUT1) expression in monocytes (F = 21.46, P = 2.9 × 10^-5, Q = 0.0004). The most robust predictors, monocyte GLUT1 and T helper cell CD36, were used to develop a diagnostic model, which showed a leave-one-out cross-validated area under the receiver operating characteristic curve (AUC) of 0.78 (95% CI: 0.66-0.92). The diagnostic model was validated in two independent datasets. The model was able to distinguish first-onset, drug-naïve schizophrenia patients (n = 34) from healthy controls (n = 39) with an AUC of 0.75 (95% CI: 0.64-0.86), and also differentiated schizophrenia patients (n = 22) from patients with other neuropsychiatric conditions, including bipolar disorder, major depressive disorder and autism spectrum disorder (n = 68), with an AUC of 0.83 (95% CI: 0.75-0.92). These findings indicate that PBMC-derived biomarkers have the potential to support an accurate and objective differential diagnosis of schizophrenia.

Metabolic Hormones in Schizophrenia Patients with Antipsychotic-Induced Metabolic Syndrome

Metabolic syndrome (MetS) is a common complication of schizophrenia that is quite exacerbated by long-term use of (atypical) antipsychotics. The mechanism of MetS has neuronal, neuroendocrine, and neuroimmunological components and shows some overlap with those of aspects of schizophrenia. We examined 195 patients with schizophrenia (90 with and 105 without MetS) for the association of serum levels of ghrelin, insulin, and leptin with metabolic abnormalities. Serum glucose levels and lipid profiles were routinely measured with colorimetric enzymatic methods and hormone levels with multiplex analyzers. Leptin levels were highly significantly increased (p < 0.001) in people with MetS (9.966 [5.882; 21.496] vs. 6.35 [2.005; 11.753], Me [Q1; Q3]) and ghrelin levels were actually significantly decreased (p = 0.045). Insulin levels did not differ significantly between those with and without MetS (p = 0.162). In Spearman’s correlation analysis between the hormone levels, body characteristics, and biochemical parameters, significant correlations were seen somewhat more often in people without MetS than in those with MetS and also less often for ghrelin than for the other hormones. We conclude that evidence exists for a role in the development of MetS especially for leptin, but that less is supporting a role for ghrelin.

The role of hypothalamic endoplasmic reticulum stress in schizophrenia and antipsychotic-induced weight gain: A narrative review

Schizophrenia (SCZ) is a serious mental illness that affects 1% of people worldwide. SCZ is associated with a higher risk of developing metabolic disorders such as obesity. Antipsychotics are the main treatment for SCZ, but their side effects include significant weight gain/obesity. Despite extensive research, the underlying mechanisms by which SCZ and antipsychotic treatment induce weight gain/obesity remain unclear. Hypothalamic endoplasmic reticulum (ER) stress is one of the most important pathways that modulates inflammation, neuronal function, and energy balance. This review aimed to investigate the role of hypothalamic ER stress in SCZ and antipsychotic-induced weight gain/obesity. Preliminary evidence indicates that SCZ is associated with reduced dopamine D2 receptor (DRD2) signaling, which significantly regulates the ER stress pathway, suggesting the importance of ER stress in SCZ and its related metabolic disorders. Antipsychotics such as olanzapine activate ER stress in hypothalamic neurons. These effects may induce decreased proopiomelanocortin (POMC) processing, increased neuropeptide Y (NPY) and agouti-related protein (AgRP) expression, autophagy, and leptin and insulin resistance, resulting in hyperphagia, decreased energy expenditure, and central inflammation, thereby causing weight gain. By activating ER stress, antipsychotics such as olanzapine activate hypothalamic astrocytes and Toll-like receptor 4 signaling, thereby causing inflammation and weight gain/obesity. Moreover, evidence suggests that antipsychotic-induced ER stress may be related to their antagonistic effects on neurotransmitter receptors such as DRD2 and the histamine H1 receptor. Taken together, ER stress inhibitors could be a potential effective intervention against SCZ and antipsychotic-induced weight gain and inflammation.

The Effects of Use of Long-Term Second-Generation Antipsychotics on Liver and Kidney Function: A Prospective Study

(1) Background: The second-generation antipsychotics (SGAPs) induce metabolic and inflammatory side effects, but documentation of their effects on the liver and kidneys is scarce. Aim: To study the three-year fluctuation of selected markers of renal and hepatic function in forensic psychiatric patients receiving SGAPs for more than five years. (2) Methods: Thirty-five forensic psychiatric patients (N = 35) were classified into two groups according to the type of SGAPs used for their treatment and the relevant risk of weight gain and metabolic complications. The three-year medication history, anthropometric data and biochemical data relevant to renal and hepatic function were retrieved from the individual medical files, specifically: serum levels of urea, uric acid, creatinine, alkaline phosphatase and amylase; the liver function enzymes, serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and gamma-glutamyl transpeptidase(γ-GT), and also the inflammatory index C-reactive protein (CRP). (3) Results: The patients receiving the SGAPs with a low risk for weight gain showed no significant fluctuation in the biochemical markers over the three-year period. The patients receiving the SGAPs with a high risk for weight gain showed significant differences between at least two measurements of uric acid (p = 0.015), SGOT (p = 0.018) and SGPT (p = 0.051). They showed significantly higher levels of creatinine in the third year compared to the second year (p = 0.029), and SGOT in the second year compared to the first (p = 0.038), and lower levels of SGPT in the third year compared to the second (p = 0.024). (4) Conclusion:In addition to consideration of possible metabolic and inflammatory complications, the choice of an antipsychotic drug for long-term treatment should also take into account the risk of hepatotoxicity and kidney damage.

New Insight Concerning Therapeutic Drug Monitoring-The Importance of the Concept of Psychonephrology

Recently, the concept of psychonephrology was developed and has been recognized as a field of study that focuses on nephrology and mental health fields, such as psychiatry and psychosomatic medicine. Indeed, patients with chronic kidney disease frequently suffer from mental problems as the disease stage progresses. Most psychotropic drugs are hepatically metabolized, but some are unmetabolized and eliminated renally. However, renal disease may affect the pharmacokinetics of many psychotropic drugs, as the decreased renal function not only delays the urinary excretion of the drug and its metabolites but also alters various pharmacokinetic factors, such as protein-binding, enterohepatic circulation, and activity of drug-metabolizing enzymes. Therefore, when prescribing drug therapy for patients with both renal disease and mental issues, we should consider reducing the dosage of psychotropic drugs that are eliminated mainly via the kidney and also carefully monitor the blood drug concentrations of other drugs with a high extrarenal clearance, such as those that are largely metabolized in the liver. Furthermore, we should carefully consider the dialyzability of each psychotropic drug, as the dialyzability impacts the drug clearance in patients with end-stage renal failure undergoing dialysis. Therapeutic drug monitoring (TDM) may be a useful tool for adjusting the dosage of psychotropic drugs appropriately in patients with renal disease. We herein review the pharmacokinetic considerations for psychotropic drugs in patients with renal disease as well as those undergoing dialysis and offer new insight concerning TDM in the field of psychonephrology.

Crosstalk between Schizophrenia and Metabolic Syndrome: The Role of Oxytocinergic Dysfunction

The high prevalence of metabolic syndrome in persons with schizophrenia has spurred investigational efforts to study the mechanism beneath its pathophysiology. Early psychosis dysfunction is present across multiple organ systems. On this account, schizophrenia may be a multisystem disorder in which one organ system is predominantly affected and where other organ systems are also concurrently involved. Growing evidence of the overlapping neurobiological profiles of metabolic risk factors and psychiatric symptoms, such as an association with cognitive dysfunction, altered autonomic nervous system regulation, desynchrony in the resting-state default mode network, and shared genetic liability, suggest that metabolic syndrome and schizophrenia are connected via common pathways that are central to schizophrenia pathogenesis, which may be underpinned by oxytocin system dysfunction. Oxytocin, a hormone that involves in the mechanisms of food intake and metabolic homeostasis, may partly explain this piece of the puzzle in the mechanism underlying this association. Given its prosocial and anorexigenic properties, oxytocin has been administered intranasally to investigate its therapeutic potential in schizophrenia and obesity. Although the pathophysiology and mechanisms of oxytocinergic dysfunction in metabolic syndrome and schizophrenia are both complex and it is still too early to draw a conclusion upon, oxytocinergic dysfunction may yield a new mechanistic insight into schizophrenia pathogenesis and treatment.

Bioinformatics-based screening of key genes between maternal preeclampsia and offspring schizophrenia

Converging lines of evidence suggest an association between schizophrenia and prenatal neurodevelopmental disorders. Preeclampsia is a multisystem disease based on the coexistence of pregnancy and elevated blood pressure, which increases the risk for offspring abnormal neurodevelopment. Previous studies have showed maternal preeclampsia is associated with an increased risk of offspring schizophrenia, but the molecular mechanism remains unclear. In this study, we sought to identify key protein-coding genes between maternal preeclampsia and offspring schizophrenia. GSE53987 and GSE166846 datasets from Gene Expression Omnibus (GEO) database were analysed to obtain common differentially expressed genes (DEGs) between preeclampsia and schizophrenia. GSE62105 dataset was analysed to identify the DEGs' expressions in neural cells from one control and one schizophrenic patient. GSE92845 dataset was analysed to describe the changes of the DEGs in human neural stem cells. In total, we obtained ten common DEGs. All of them expressed differently in neural cells of the control and schizophrenic patient. We chose the six DEGs that had similar trend in both neural cells and UCB from preeclampsia patients and analysed their expressions in human neural stem cells over time. We found the expressions of CKAP5 and SAT1 in day 30 had significant difference comparing with those in day 0. The KEGG pathway analysis of their interaction proteins showed they were involved with metabolism. Our results may provide a new insight for genetic basis of relationship between maternal preeclampsia and offspring schizophrenia.

Hepatitis C-associated late-onset schizophrenia: a nationwide, population-based cohort study

BACKGROUND

Whether infection with the hepatitis C virus (HCV) causes schizophrenia - and whether the associated risk reverses after anti-HCV therapy - is unknown; we aimed to investigate these topics.

METHODS

We conducted a nationwide, population-based cohort study using the Taiwan National Health Insurance Research Database (TNHIRD). A diagnosis of schizophrenia was based on criteria from the International Classification of Diseases, 9th revision (295.xx).

RESULTS

From 2003 to 2012, from a total population of 19 298 735, we enrolled 3 propensity-score-matched cohorts (1:2:2): HCV-treated (8931 HCV-infected patients who had received interferon-based therapy for ≥ 6 months); HCV-untreated (17 862); and HCV-uninfected (17 862) from the TNHIRD. Of the total sample (44 655), 82.81% (36 980) were 40 years of age or older. Of the 3 cohorts, the HCV-untreated group had the highest 9-year cumulative incidence of schizophrenia (0.870%, 95% confidence interval [CI] 0.556%-1.311%; p < 0.001); the HCV-treated (0.251%, 95% CI 0.091%-0.599%) and HCV-uninfected (0.118%, 95% CI 0.062%-0.213%) cohorts showed similar cumulative incidence of schizophrenia (p = 0.33). Multivariate Cox analyses showed that HCV positivity (hazard ratio [HR] 3.469, 95% CI 2.168-5.551) was independently associated with the development of schizophrenia. The HCV-untreated cohort also had the highest cumulative incidence of overall mortality (20.799%, 95% CI 18.739%-22.936%; p < 0.001); the HCV-treated (12.518%, 95% CI 8.707%-17.052%) and HCV uninfected (6.707%, 95% CI 5.533%-8.026%) cohorts showed similar cumulative incidence of mortality (p = 0.12).

LIMITATIONS

We were unable to determine the precise mechanism of the increased risk of schizophrenia in patients with HCV infection.

CONCLUSION

In a population-based cohort (most aged ≥ 40 years), HCV positivity was a potential risk factor for the development of schizophrenia; the HCV-associated risk of schizophrenia might be reversed by interferon-based antiviral therapy.

Evaluation of IGF-1 as a novel theranostic biomarker for schizophrenia

OBJECTIVE

In the current study, we aimed to investigate fasting plasma levels of glucose, insulin, growth hormone, IGF-1, and lipid profile in remission schizophrenia patients, treatment resistant schizophrenia patients and healthy controls and to determine whether IGF-1 levels can be used as a theranostic biomarker in schizophrenia.

METHODS

Sixty-two patients under remission from schizophrenia, sixty-five treatment-resistant patients with schizophrenia and sixty-two healthy controls were included in the study. All patients were recruited and evaluated over 11 months. Symptoms at the time of evaluation were assessed twice using BPRS, PANSS, CGI, and GAF scales by an experienced psychiatrist in accordance with Andreaseen's remission criteria and TRIPS group resistance criteria. Blood samples were collected from all participants to determine fasting glucose, LDL, HDL, Triglyceride, Total Cholesterol, fasting, insulin, GH and IGF-1 levels.

RESULTS

Fasting blood glucose levels were found to be higher in patients with schizophrenia than in healthy controls. Moreover, LDL levels of the treatment sensitive group were higher than that of the treatment resistant group while they were not significantly different from the healthy controls. IGF-1 levels were lower in the treatment sensitive group than in both treatment resistant and healthy control groups. IGF-1, LDL and age of disease onset were found to be significantly associated with treatment resistance in a regression model.

DISCUSSION

In the present study, remitted patients with schizophrenia could be distinguished from treatment-resistant patients and healthy controls with serum IGF-1, fasting glucose and LDL levels. In addition, we found that smoking and age of disease onset together with IGF-1 levels could significantly predict resistance to treatment.

Metabolomics-based understanding of the olanzapine-induced weight gain in female first-episode drug-naïve patients with schizophrenia

Previous studies have demonstrated that patients with schizophrenia (SZ) have greater rate of metabolic disorder as compared with the control population, which likely be the consequence of use of atypical antipsychotics. Olanzapine is a widely used antipsychotic, which increases the weight of SZ patients. However, the underlying mechanism remains poorly understood. Here we report the metabolomics-based understanding of the weight gain induced by olanzapine. 57 first-episode drug-naïve patients (FEDN) were recruited, of whom 27 patients completed a 4-week clinical trial. We then profiled the metabolomes of their plasma with the LC-MS-based nontargeted metabolomics approach at the baseline and after olanzapine monotherapy for 4 weeks. We observed that the plasma of the olanzapine-treated patient had significantly higher lysophosphatidylcholine (LysoPC), lysophosphatidylethanolamine (LysoPE) and lower carnitine as compared with that of the baseline plasma samples. Moreover, regression analyses indicated that the change of LysoPC(14:0) level was an independent contributor to the olanzapine-induced weight gain. Our study suggests that the metabolomics-based approach may facilitate the identification of biomarkers associated with the metabolic disorder causing by antipsychotic in schizophrenia patients.

Kynurenine metabolism and metabolic syndrome in patients with schizophrenia

Accumulating evidence indicates that a dysregulated kynurenine (KYN) pathway (KP) metabolism may play an important role in the pathogenesis of both schizophrenia and metabolic syndrome (MS). However, the underlying mechanisms remain poorly understood. Here, we aimed to evaluate the potential roles of KP in the pathogenesis of MS in schizophrenia. A total of 160 schizophrenia patients and 70 healthy controls were enrolled in this study. KP metabolites were quantified, and MS scores were calculated, for comparisons between patients and controls. Associations among the indices were explored in both groups. Multiple linear regression analyses were performed to investigate the effects of KP metabolites on MS factors. We observed a significantly higher MS score, lower levels of all KP metabolites, and higher nicotinamide adenine dinucleotide (NAD⁺)/quinolinic acid (QUNA) in patients than in controls (all p < 0.01). Partial correlation analyses revealed that, in the patient group, QUNA and QUNA/KYN correlated positively with MS score (r = 0.24 and 0.27, respectively, both p < 0.025), and NAD⁺/QUNA correlated negatively with MS score (r = -0.25, p = 0.002). Results of multiple regression analyses showed significant QUNA × group interactions in the model representing QUNA effects on MS score (β = 0.25) and a significant QUNA/KYN × group interaction in the model representing QUNA/KYN effects on MS score (β = 0.23) (both p < 0.001). Among all factors contributing to MS in schizophrenia, an interactive effect of schizophrenia itself and dysregulated KP plays a contributory role. Conceivably, modulation of the KP could theoretically lead to treating schizophrenia and MS simultaneously.

Risk factors for natural cause mortality in a cohort of 1494 persons with serious mental illness

Persons with serious mental illness die on average more than 10 years younger than those in the overall population, mostly due to natural causes. Previous studies have identified predictors of natural cause mortality in this population but few have been prospective studies using clinical variables from in-person evaluations. A cohort of 1494 individuals with schizophrenia, bipolar disorder, or major depressive disorder were assessed at baseline and mortality status was determined from the US National Death Index after up to 20 years of follow-up. Analyses included multivariate Cox proportional hazard models to determine independent predictors of natural cause mortality. A total of 125 (8.4%) individuals died of natural causes. In multivariate models, the strongest predictor of mortality after age was tobacco smoking at baseline with a dose-related effect. Having diabetes, a cardiovascular condition, particularly hypertension, and lower cognitive functioning were also significant risks, along with divorced/separated status. The receipt of gabapentin or fluoxetine also significantly increased mortality risk. Premature death can be reduced by smoking cessation and the improved management of conditions such as hypertension and diabetes.

Understanding Mechanisms Underlying Non-Alcoholic Fatty Liver Disease (NAFLD) in Mental Illness: Risperidone and Olanzapine Alter the Hepatic Proteomic Signature in Mice

Patients with severe mental illness have increased mortality, often linked to cardio-metabolic disease. Non-alcoholic fatty liver disease (NAFLD) incidence is higher in patients with schizophrenia and is exacerbated with antipsychotic treatment. NAFLD is associated with obesity and insulin resistance, both of which are induced by several antipsychotic medications. NAFLD is considered an independent risk factor for cardiovascular disease, the leading cause of death for patients with severe mental illness. Although the clinical literature clearly defines increased risk of NAFLD with antipsychotic therapy, the underlying mechanisms are not understood. Given the complexity of the disorder as well as the complex pharmacology associated with atypical antipsychotic (AA) medications, we chose to use a proteomic approach in healthy mice treated with a low dose of risperidone (RIS) or olanzapine (OLAN) for 28 days to determine effects on development of NAFLD and to identify pathways impacted by AA medications, while removing confounding intrinsic effects of mental illness. Both AA drugs caused development of steatosis in comparison with vehicle controls (p < 0.01) and affected multiple pathways relating to energy metabolism, NAFLD, and immune function. AA-associated alteration in autonomic function appears to be a unifying theme in the regulation of hepatic pathology.

The metabolic effects of antipsychotics in the early stage of treatment in first-episode patients with schizophrenia: A real-world study in a naturalistic setting

OBJECTIVE

This study aims to better characterize the metabolic effects of antipsychotics in the early stage of treatment in first-episode patients with schizophrenia.

METHODS

We performed a retrospective real-world study in a naturalistic setting that included inpatients with first-episode drug-naïve schizophrenia; metabolic profiles were measured at baseline and 2 weeks and 4 weeks after antipsychotic treatment. The metabolic profiles of medicated patients with first-episode schizophrenia were also included.

RESULTS

Insulin resistance, based on the ratio of triglycerides to high-density lipoprotein cholesterol (TG/HDL-C), increased significantly after 2 weeks of antipsychotic treatment, whereas fasting glucose (FG) decreased significantly. Regarding lipid metabolism, triglycerides (TG), cholesterol (CHOL) and low-density lipoprotein cholesterol (LDL-C) increased significantly after 2 weeks of antipsychotic treatment; however, high-density lipoprotein cholesterol (HDL-C) decreased significantly after 4 weeks of antipsychotic treatment. There were no statistically significant differences between the antipsychotic groups in any of the metabolic parameters evaluated.

CONCLUSION

Our study revealed that insulin resistance and lipid metabolic abnormalities occurred as early as two weeks after the initiation of antipsychotic treatment. Our findings suggest that metabolic profiles should been monitored in the early stage of antipsychotics treatment in clinical practice. Further research is needed to explore the underlying mechanisms of the short-term effects of antipsychotics on metabolic parameters.

Accumulation rate of advanced glycation end products in recent onset psychosis: A longitudinal study

Schizophrenia is associated with excessive oxidative stress. Production of advanced glycation end products (AGEs) in the skin is strongly associated with oxidative stress. Increased skin AGE-levels have been demonstrated at cross-sectional level in recent onset psychosis and chronic schizophrenia, indicating increased cardiovascular risk. We aimed to investigate factors underlying AGE-accumulation and accumulation rate of AGEs in recent onset psychosis. From December 2016 through May 2017, 66 patients and 160 (highly educated) healthy controls from a previous case-control study of AGE-levels were assessed for a follow-up measurement 12-24 months after baseline. Possible determinants of AGE-accumulation were analyzed. AGE-accumulation rates in patients and controls were compared adjusted for relevant confounders. In healthy controls, a significant association of AGE-accumulation with ethnicity and tobacco exposure was found. An indication of a markedly higher AGE-accumulation rate was found in patients suffering from recent onset psychosis compared to healthy controls, independent of ethnicity and tobacco smoking, but not independent of cannabis use (more prevalent in patients than controls), although results were not significant.

Ketogenic therapy in neurodegenerative and psychiatric disorders: From mice to men

Ketogenic diet is a low carbohydrate and high fat diet that has been used for over 100 years in the management of childhood refractory epilepsy. More recently, ketogenic diet has been investigated for a number of metabolic, neurodegenerative and neurodevelopmental disorders. In this comprehensive review, we critically examine the potential therapeutic benefits of ketogenic diet and ketogenic agents on neurodegenerative and psychiatric disorders in humans and translationally valid animal models. The preclinical literature provides strong support for the efficacy of ketogenic diet in a variety of diverse animal models of neuropsychiatric disorders. However, the evidence from clinical studies, while encouraging, particularly in Alzheimer's disease, psychotic and autism spectrum disorders, is limited to case studies and small pilot trials. Firm conclusion on the efficacy of ketogenic diet in psychiatric disorders cannot be drawn due to the lack of randomised, controlled clinical trials. The potential mechanisms of action of ketogenic therapy in these disorders with diverse pathophysiology may include energy metabolism, oxidative stress and immune/inflammatory processes. In conclusion, while ketogenic diet and ketogenic substances hold promise pre-clinically in a variety of neurodegenerative and psychiatric disorders, further studies, particularly randomised controlled clinical trials, are warranted to better understand their clinical efficacy and potential side effects.

Effects of beta-hydroxybutyrate administration on MK-801-induced schizophrenia-like behaviour in mice

RATIONALE

Impaired cerebral glucose metabolism is a core pathological feature of schizophrenia. We recently demonstrated that a ketogenic diet, causing a shift from glycolysis to ketosis, normalized schizophrenia-like behaviours in an acute N-methyl-D-aspartate (NMDA) receptor antagonist model of the illness. Ketogenic diet produces the ketone body, β-hydroxybutyrate (BHB), which may serve as an alternative fuel source in its own right without a strict dietary regime.

OBJECTIVE

We hypothesized that chronic administration of BHB replicates the therapeutic effects of ketogenic diet in an acute NMDA receptor hypofunction model of schizophrenia in mice.

METHODS

C57Bl/6 mice were either treated with acute doses of 2 mmol/kg, 10 mmol/kg, or 20 mmol/kg BHB or received daily intraperitoneal injections of 2 mmol/kg BHB or saline for 3 weeks. Behavioural testing assessed the effect of acute challenge with 0.2 mg/kg MK-801 or saline on open field behaviour, social interaction, and prepulse inhibition of startle (PPI).

RESULTS

Acute BHB administration dose-dependently increased BHB plasma levels, whereas the 2 mmol/kg dose increased plasma glucose levels. The highest acute dose of BHB supressed spontaneous locomotor activity, MK-801-induced locomotor hyperactivity and MK-801-induced disruption of PPI. Chronic BHB treatment normalized MK-801-induced hyperlocomotion, reduction of sociability, and disruption of PPI.

CONCLUSION

In conclusion, BHB may present a novel treatment option for patients with schizophrenia by providing an alternative fuel source to normalize impaired glucose metabolism in the brain.

Studies on Haloperidol and Adjunctive α-Mangostin or Raw Garcinia mangostana Linn Pericarp on Bio-Behavioral Markers in an Immune-Inflammatory Model of Schizophrenia in Male Rats

Schizophrenia is a severe brain disorder that is associated with neurodevelopmental insults, such as prenatal inflammation, that introduce redox-immune-inflammatory alterations and risk for psychotic symptoms later in life. Nutraceuticals may offer useful adjunctive benefits. The aim of this study was to examine the therapeutic effects of Garcinia mangostana Linn (GML) and one of its active constituents, α-mangostin (AM), alone and as adjunctive treatment with haloperidol (HAL) on schizophrenia related bio-behavioral alterations in a maternal immune-activation (MIA) model. Sprague-Dawley dams were exposed to lipopolysaccharide (LPS) (n = 18) or vehicle (n = 3) on gestational days 15 and 16. Male offspring (n = 72) were treated from PND 52-66 with either vehicle, HAL (2 mg/kg), GML (50 mg/kg), HAL + GML, AM (20 mg/kg), or HAL + AM. Control dams and control offspring were treated with vehicle. In order to cover the mood-psychosis continuum, prepulse inhibition (PPI) of startle, open field test (locomotor activity), and the forced swim test (depressive-like behavior) were assessed on PND's 64-65, followed by assay of frontal-cortical lipid peroxidation and plasma pro-inflammatory cytokines, viz. interleukin-1 (IL-1) and tumor necrosis factor-α (TNF-α). MIA-induced deficits in sensorimotor gating were reversed by HAL and HAL + GML, but not GML and AM alone. MIA-induced depressive-like behavior was reversed by AM and GML alone and both in combination with HAL, with the combinations more effective than HAL. MIA-induced cortical lipid peroxidation was reversed by HAL and AM, with elevated IL-6 levels restored by GML, AM, HAL, and HAL + GML. Elevated TNF-α was only reversed by GML and HAL + GML. Concluding, prenatal LPS-induced psychotic- and depressive-like bio-behavioral alterations in offspring are variably responsive to HAL, GML, and AM, with depressive (but not psychosis-like) manifestations responding to GML, AM, and combinations with HAL. AM may be a more effective antioxidant than GML in vivo, although this does not imply an improved therapeutic response, for which trials are required.

Childhood trauma and glucose metabolism in patients with first-episode psychosis

Although the associations between first-episode psychosis (FEP) and metabolic abnormalities on one side, and childhood trauma (CT) and risk of developing psychosis on the other are both well established, evidence on the relationship between CT and metabolic dysregulation in terms of abnormal glucose metabolism is very limited. We tested whether, already at illness onset, FEP patients with a history of CT show dysregulation of a broad range of glucose metabolism markers. In particular, in 148 FEP patients we evaluated serum concentrations of c-peptide, insulin, plasminogen-activator-inhibitor-1 (PAI-1), resistin, visfatin, glucagon, glucagon-like peptide-1 (GLP-1), gastric-inhibitor-peptide (GIP), leptin, and ghrelin. We also assessed CT with the Childhood Experience of Care and Abuse Questionnaire, and stressful life events (SLEs) with a semi-structured interview. Psychopathology, cannabis and tobacco habits, Body Mass Index (BMI) were recorded. Serum concentrations of markers were analyzed from peripheral blood. Ninety-five patients (56 % males, mean age 29.5) reported CT. Multivariate models showed that CT is associated only with the concentrations of c-peptide and insulin after adjusting for age, sex, BMI and SLEs. FEP patients who had experienced CT showed higher c-peptide and insulin serum concentrations. Our study reports that CT might be associated with the metabolic abnormalities in the first stage of psychosis, suggesting that a thorough anamnestic evaluation at psychosis onset that would include the history of CT could be helpful for clinicians in order to implement early programmes of healthy lifestyle education and to guide choice of therapeutic interventions for trauma.

The dosage-dependent effects of cevimeline in preventing olanzapine-induced metabolic side-effects in female rats

Olanzapine has been used for the treatment of schizophrenia and other mental disorders. However, it is associated with serious weight gain and other metabolic side-effects. The antagonistic affinity of olanzapine to muscarinic M3 receptors has been evidenced as one of the main contributors for its weight gain and other metabolic side-effects. Therefore, this study investigated whether the co-treatment of cevimeline (a M3 receptor agonist) could prevent the metabolic side-effects associated with olanzapine medication. Female Sprague Dawley rats were treated orally with olanzapine (2 mg/kg, t.i.d.) and/or cevimeline at 3 dosages (3, 6, 9 mg/kg, t.i.d.), or vehicle for two weeks. Weight gain and food/water intake were measured throughout the drug treatment period. Intraperitoneal glucose tolerance tests and open field tests were conducted. Olanzapine-treated rats demonstrated significantly elevated body weight gain, food intake, feeding efficiency, total white fat mass, liver mass, and plasma triglyceride levels, which could be partly reversed by the co-treatment with cevimeline in a dosage-dependent manner. In general, the body weight gain can only be reversed by the co-treatment of 9 mg/kg cevimeline. The cevimeline co-treatment decreased plasma triglyceride and glucose levels compared with olanzapine only treatment. The results suggested a dosage-dependent effect of cevimeline in ameliorating olanzapine-induced weight gain and metabolic side-effects, which supports further clinical trials using cevimeline to control weight gain and metabolic side-effects caused by antipsychotic medications.

Recent strategies and advances in the fabrication of nano lipid carriers and their application towards brain targeting

In last two decades, the lipid nanocarriers have been extensively investigated for their drug targeting efficiency towards the critical areas of the human body like CNS, cardiac region, tumor cells, etc. Owing to the flexibility and biocompatibility, the lipid-based nanocarriers, including nanoemulsion, liposomes, SLN, NLC etc. have gained much attention among various other nanocarrier systems for brain targeting of bioactives. Across different lipid nanocarriers, NLC remains to be the safest, stable, biocompatible and cost-effective drug carrier system with high encapsulation efficiency. Drug delivery to the brain always remains a challenging issue for scientists due to the complex structure and various barrier mechanisms surrounding the brain. The application of a suitable nanocarrier system and the use of any alternative route of drug administration like nose-to-brain drug delivery could overcome the hurdle and improves the therapeutic efficiency of CNS acting drugs thereof. NLC, a second-generation lipid nanocarrier, upsurges the drug permeation across the BBB due to its unique structural properties. The biocompatible lipid matrix and nano-size make it an ideal drug carrier for brain targeting. It offers many advantages over other drug carrier systems, including ease of manufacturing and scale-up to industrial level, higher drug targeting, high drug loading, control drug release, compatibility with a wide range of drug substances, non-toxic and non-irritant behavior. This review highlights recent progresses towards the development of NLC for brain targeting of bioactives with particular reference to its surface modifications, formulations aspects, pharmacokinetic behavior and efficacy towards the treatment of various neurological disorders like AD, PD, schizophrenia, epilepsy, brain cancer, CNS infection (viral and fungal), multiple sclerosis, cerebral ischemia, and cerebral malaria. This work describes in detail the role and application of NLC, along with its different fabrication techniques and associated limitations. Specific emphasis is given to compile a summary and graphical data on the area explored by scientists and researchers worldwide towards the treatment of neurological disorders with or without NLC. The article also highlights a brief insight into two prime approaches for brain targeting, including drug delivery across BBB and direct nose-to-brain drug delivery along with the current global status of specific neurological disorders.

The Other Obesity Epidemic-Of Drugs and Bugs

Chronic psychiatric patients with schizophrenia and related disorders are frequently treatment-resistant and may require higher doses of psychotropic drugs to remain stable. Prolonged exposure to these agents increases the risk of weight gain and cardiometabolic disorders, leading to poorer outcomes and higher medical cost. It is well-established that obesity has reached epidemic proportions throughout the world, however it is less known that its rates are two to three times higher in mentally ill patients compared to the general population. Psychotropic drugs have emerged as a major cause of weight gain, pointing to an urgent need for novel interventions to attenuate this unintended consequence. Recently, the gut microbial community has been linked to psychotropic drugs-induced obesity as these agents were found to possess antimicrobial properties and trigger intestinal dysbiosis, depleting Bacteroidetes phylum. Since germ-free animals exposed to psychotropics have not demonstrated weight gain, altered commensal flora composition is believed to be necessary and sufficient to induce dysmetabolism. Conversely, not only do psychotropics disrupt the composition of gut microbiota but the later alter the metabolism of the former. Here we review the role of gut bacterial community in psychotropic drugs metabolism and dysbiosis. We discuss potential biomarkers reflecting the status of Bacteroidetes phylum and take a closer look at nutritional interventions, fecal microbiota transplantation, and transcranial magnetic stimulation, strategies that may lower obesity rates in chronic psychiatric patients.

Ketogenic diet and olanzapine treatment alone and in combination reduce a pharmacologically-induced prepulse inhibition deficit in female mice

We used the acute NMDA receptor hypoactivity model of schizophrenia in mice to compare the efficacy of a long-term ketogenic diet and a commonly used antipsychotic, olanzapine, and to explore the interaction between these treatments. We found that a ketogenic diet in female mice was as effective as olanzapine to diminish MK-801-induced disruption of prepulse inhibition (PPI). Furthermore, combination of the diet with olanzapine treatment resulted in a similar effect compared to either treatment alone. These results suggest that ketogenic diet can be used effectively together with antipsychotics drugs over an extended period.

Pharmacotherapy of schizophrenia: toward a metabolomic-based approach

Approximately 20%-30% of schizophrenia patients are resistant to current standard pharmacotherapies. Recent schizophrenia research aims to identify specific pathophysiological abnormalities and novel targets in the disease, with the goals of identifying at-risk individuals, facilitating diagnosis, prompting early and personalized interventions, and helping predict response to treatment. Metabolomics involves the systematic study of the profile of biochemical alterations early in the course of a given disorder. Major aspects of the schizophrenia metabolome have been characterized, uncovering potential selective biomarkers for the disease that may change how the disorder is diagnosed, and how patients are stratified and treated. This review focuses on the most common metabolomic fingerprints of the different pathways involved in the pathophysiology of schizophrenia, and the potential development of novel metabolomic-related pharmacotherapies for improved treatment of schizophrenia and other related idiopathic psychotic disorders.

[A Multifaceted Approach regarding the Association of the DsbA-L Gene with the Risk of Obesity-related Diseases Based on Clinical Pharmacogenetics]

Adiponectin, the most abundant adipose tissue-derived adipocytokine, improves insulin sensitivity and has anti-inflammatory properties. Disulfide-bond A oxidoreductase-like protein (DsbA-L) is a key molecule in the multimerization of adiponectin (i.e., activation of adiponectin). In mice, liver-specific knockout of the Dsba-L gene impaired the mitochondrial function in hepatocytes and exacerbated the high-fat-diet-induced fatty liver. In addition, the DsbA-L mRNA level is negatively correlated with body mass index (BMI) in humans. We recently investigated the clinical impact of the DsbA-L gene on lifestyle-related diseases in Japanese subjects. We confirmed the influence of the common DsbA-L rs1917760 polymorphism on the multimerization of adiponectin, as well as the association of the polymorphism with the risk of obesity and non-alcoholic fatty liver disease, using prediction models based on a non-linear mixed effect model and/or structural equation models among elderly participants in a health screening program. We also observed a decreasing effect of DsbA-L polymorphism on the DsbA-L mRNA level in peripheral blood mononuclear cells, and an increasing effect of the polymorphism on the prevalence of excessive weight among schizophrenia patients at a high risk for obesity. These findings suggest that DsbA-L may be a key molecule associated with the development and progression of obesity and its related diseases. Therefore, genotyping the DsbA-L polymorphism and identifying patients at a high risk of developing obesity may help prevent obesity and its complications by facilitating targeted prevention and treatment programs for high-risk individuals.

Insulin Resistance in Schizophrenia

Schizophrenia and diabetes have been known to be linked disorders for decades. One reason is due to the fact that a major side effect of antipsychotic medication treatment is metabolic syndrome, which increases the risk of the patients developing type 2 diabetes and cardiovascular disorders. However, signs of metabolic syndrome in schizophrenia patients were identified more than 100 years ago, even before the development of antipsychotic drugs. This suggests that schizophrenia itself predisposes towards diabetes and, in turn, insulin resistance may be a risk factor for the development of schizophrenia. This review summarizes the findings surrounding this issue and places them into context with regards to increasing our understanding of the aetiology of schizophrenia and in support of biomarker and drug discovery efforts.

Proteomic Studies of Psychiatric Disorders

Many diseases result from programming effects in utero. This chapter describes recent advances in proteomic studies which have improved our understanding of the underlying pathophysiological pathways in the major psychiatric disorders, resulting in the development of potential novel biomarker tests. Such tests should be based on measurement of blood-based proteins given the ease of accessibility of this medium and the known connections between the periphery and the central nervous system. Most importantly, emerging biomarker tests should be developed on lab-on-a-chip and other handheld devices to enable point-of-care use. This should help to identify individuals with psychiatric disorders much sooner than ever before, which will allow more rapid treatment options for the best possible patient outcomes.

The Therapeutic Potential of Ketogenic Diet Throughout Life: Focus on Metabolic, Neurodevelopmental and Neurodegenerative Disorders

This chapter reviews the efficacy of the ketogenic diet in a variety of neurodegenerative, neurodevelopmental and metabolic conditions throughout different stages of life. It describes conditions affecting children, metabolic disorders in adults and disorderrs affecting the elderly. We have focused on application of the ketogenic diet in clinical studies and in preclinical models and discuss the benefits and negative aspects of the diet. Finally, we highlight the need for further research in this area with a view of discovering novel mechanistic targets of the ketogenic diet, as a means of maximising the potential benefits/risks ratio.

Temporal proteomic profiling of postnatal human cortical development

Healthy cortical development depends on precise regulation of transcription and translation. However, the dynamics of how proteins are expressed, function and interact across postnatal human cortical development remain poorly understood. We surveyed the proteomic landscape of 69 dorsolateral prefrontal cortex samples across seven stages of postnatal life and integrated these data with paired transcriptome data. We detected 911 proteins by liquid chromatography-mass spectrometry, and 83 were significantly associated with postnatal age (FDR < 5%). Network analysis identified three modules of co-regulated proteins correlated with age, including two modules with increasing expression involved in gliogenesis and NADH metabolism and one neurogenesis-related module with decreasing expression throughout development. Integration with paired transcriptome data revealed that these age-related protein modules overlapped with RNA modules and displayed collinear developmental trajectories. Importantly, RNA expression profiles that are dynamically regulated throughout cortical development display tighter correlations with their respective translated protein expression compared to those RNA profiles that are not. Moreover, the correspondence between RNA and protein expression significantly decreases as a function of cortical aging, especially for genes involved in myelination and cytoskeleton organization. Finally, we used this data resource to elucidate the functional impact of genetic risk loci for intellectual disability, converging on gliogenesis, myelination and ATP-metabolism modules in the proteome and transcriptome. We share all data in an interactive, searchable companion website. Collectively, our findings reveal dynamic aspects of protein regulation and provide new insights into brain development, maturation, and disease.

Leptin/Adiponectin ratio as a potential biomarker for metabolic syndrome in patients with schizophrenia

OBJECTIVE

Leptin and adiponectin are adipokines which have opposing roles in the development of insulin resistance and metabolic syndrome (MetS). Leptin/adiponectin ratio (L/A ratio) has been proposed as a good biomarker for MetS in general population. This study aimed to compare the strength of association between MetS and leptin, adiponectin and L/A ratio, as well as to assess their performance to diagnose MetS in patients with schizophrenia.

METHODS

Patients diagnosed with DSM-IV schizophrenia and under clozapine or olanzapine monotherapy for at least six months were recruited. We used the modified ATP III criteria for Asians to evaluate subjects for a diagnosis of MetS.

RESULTS

We recruited 262 study subjects with schizophrenia, and classified them into those with MetS (n = 87) and those without MetS (n = 175). Leptin level was positively correlated with BMI, waist circumference, and insulin level. Adiponectin level was negatively correlated with most metabolic parameters, except glucose level. L/A ratio was positively correlated with most metabolic parameters, except levels of glucose and HDL-C. Significant gender differences existed in leptin levels, adiponectin levels, and L/A ratio. Without and with adjustment of age and gender, binary logistic regression analysis showed that leptin level, adiponectin level, and L/A ratio were significantly associated with MetS. The area under curve (AUC) of L/A ratio and leptin level for MetS was 0.744 (95% CI = 0.685-0.802) and 0.666 (95% CI = 0.601-0.731). The AUC of adiponectin level for the absence of MetS was 0.717 (95% CI = 0.655-0.780). The discriminative strength of L/A ratio for MetS was better in men than in women.

CONCLUSIONS

The present study results suggest that L/A ratio may be a preferential marker of metabolic syndrome in patients with schizophrenia compared to leptin or adiponectin alone.

Profiling of Amino Acids and Their Derivatives Biogenic Amines Before and After Antipsychotic Treatment in First-Episode Psychosis

Schizophrenia (SCH) is a heterogeneous disorder, deriving from a potential multitude of etiopathogenetic factors. During the past few years there has been an increasing interest in the role of circulating amino acids (AAs) and biogenic amines (BAs) in the pathophysiology of SCH. In the present study, we aimed to provide an insight into the potential role of alterations in levels of AAs and BAs as well as examine their more specific metabolic shifts in relation to early stage of SCH. We measured 21 AAs and 17 BAs in serum samples of patients with first-episode psychosis (FEP) before and after 7-month antipsychotic treatment in comparison to control subjects (CSs). According to multivariate analysis, antipsychotic-naïve FEP patients had significantly higher levels of taurine and spermine, whereas values of proline (Pro), alpha-aminoadipic acid (alpha-AAA), kynurenine (Kyn), valine (Val), tyrosine (Tyr), citrulline (Citr), tryptophan (Trp), and histidine (His) were diminished compared to CSs. Increased levels of taurine and spermine, as well as reduced levels of alpha-AAA and Kyn probably reflect the compromised function of N-methyl-D-aspartate (NMDA) receptors in patients. The decreased levels of Pro (AA modulating the function of glutamate decarboxylase) likely reflect the imbalanced function of gamma-aminobutyric acid (GABA) system in the brain of FEP patients. The alterations in ratio between Tyr and phenylalanine (Phe) can be taken as a sign of compromised function of dopaminergic system. These metabolic shifts were reinstated by 7-month antipsychotic treatment. Serum metabolic profiles can be regarded as important indicators to investigate clinical course of SCH and treatment response.

T4 and waist:hip ratio as biomarkers of antipsychotic-induced weight gain in Han Chinese inpatients with schizophrenia

Second-generation antipsychotic agents (SGAs) cause serious metabolic side effects, including weight gain, dyslipidemia, and glucose metabolism abnormalities, which occur by unknown mechanisms. Therefore, the search for prospective markers for antipsychotic-induced weight gain (AIWG) has been of major interest. So far, predictive factors predisposing patients to the develop obesity and related metabolic disturbances induced by SGAs have been relatively less studied among large samples of Chinese schizophrenic patients. In this study, 264 Han Chinese inpatients diagnosed with schizophrenia or schizoaffective disorder initiated treatment with olanzapine (n=131) or risperidone (n=133) and were followed for 12weeks. Anthropometric measurements and laboratory analyses of thyroid hormone, fasting plasma glucose (FPG), and lipid levels were conducted as part of routine medical care. The results showed baseline thyroxine (T₄) and waist:hip ratio (WHR)were negatively correlated to AIWG (T₄: r_s=-0.154, P=0.014; WHR: r_s=-0.199, P=0.008). Correlations remained significant after multiple regression analyses. The two treatment groups statistically differed for changes in body mass index, WHR, LDL cholesterol, and FPG; in both groups FPG decreased at first and then increased. Our findings suggest basal T₄ and WHR may serve as early biomarkers for weight gain as a side effect of single-SGA treatment.

Blood-Based Lipidomics Approach to Evaluate Biomarkers Associated With Response to Olanzapine, Risperidone, and Quetiapine Treatment in Schizophrenia Patients

This is the first study to identify lipidomic markers in plasma associated with response of acutely ill schizophrenia patients in response to specific antipsychotic treatments. The study population included 54 schizophrenia patients treated with antipsychotics for 6 weeks. Treatment led to significant improvement in positive and negative symptoms for 34 patients with little or no improvement for 20 patients. In addition, 37 patients showed an increase in body mass index after the 6 week treatment period, consistent with effects on metabolism and the association of such effects with symptom improvement. Profiling of plasma samples taken prior to therapy using liquid chromatography tandem mass spectrometry (LC-MS/MS) resulted in identification of 38, 10, and 52 compounds associated with the olanzapine, risperidone, and quetiapine treatment groups, which could be used to distinguish responders from non-responders. Limitations include the retroactive active nature of the study and the small sample size. Further investigations with larger sample sets could lead to the development of a molecular test that could be used to help psychiatrists determine the best treatment options for each patient.

Antipsychotic Drugs: From Receptor-binding Profiles to Metabolic Side Effects

BACKGROUND

Antipsychotic-induced metabolic side effects are major concerns in psychopharmacology and clinical psychiatry. Their pathogenetic mechanisms are still not elucidated.

METHODS

Herein, we review the impact of neurotransmitters on metabolic regulation, providing insights into antipsychotic-induced metabolic side effects.

RESULTS

Antipsychotic drugs seem to interfere with feeding behaviors and energy balance, processes that control metabolic regulation. Reward and energy balance centers in central nervous system constitute the central level of metabolic regulation. The peripheral level consists of skeletal muscles, the liver, the pancreas, the adipose tissue and neuroendocrine connections. Neurotransmitter receptors have crucial roles in metabolic regulation and they are also targets of antipsychotic drugs. Interaction of antipsychotics with neurotransmitters could have both protective and harmful effects on metabolism.

CONCLUSION

Emerging evidence suggests that antipsychotics have different liabilities to induce obesity, diabetes and dyslipidemia. However this diversity cannot be explained merely by drugs'pharmacodynamic profiles, highlighting the need for further research.

System-based proteomic and metabonomic analysis of the Df(16)A+/- mouse identifies potential miR-185 targets and molecular pathway alterations

Deletions on chromosome 22q11.2 are a strong genetic risk factor for development of schizophrenia and cognitive dysfunction. We employed shotgun liquid chromatography-mass spectrometry (LC-MS) proteomic and metabonomic profiling approaches on prefrontal cortex (PFC) and hippocampal (HPC) tissue from Df(16)A^+/- mice, a model of the 22q11.2 deletion syndrome. Proteomic results were compared with previous transcriptomic profiling studies of the same brain regions. The aim was to investigate how the combined effect of the 22q11.2 deletion and the corresponding miRNA dysregulation affects the cell biology at the systems level. The proteomic brain profiling analysis revealed PFC and HPC changes in various molecular pathways associated with chromatin remodelling and RNA transcription, indicative of an epigenetic component of the 22q11.2DS. Further, alterations in glycolysis/gluconeogenesis, mitochondrial function and lipid biosynthesis were identified. Metabonomic profiling substantiated the proteomic findings by identifying changes in 22q11.2 deletion syndrome (22q11.2DS)-related pathways, such as changes in ceramide phosphoethanolamines, sphingomyelin, carnitines, tyrosine derivates and panthothenic acid. The proteomic findings were confirmed using selected reaction monitoring mass spectrometry, validating decreased levels of several proteins encoded on 22q11.2, increased levels of the computationally predicted putative miR-185 targets UDP-N-acetylglucosamine-peptide N-acetylglucosaminyltransferase 110 kDa subunit (OGT1) and kinesin heavy chain isoform 5A and alterations in the non-miR-185 targets serine/threonine-protein phosphatase 2B catalytic subunit gamma isoform, neurofilament light chain and vesicular glutamate transporter 1. Furthermore, alterations in the proteins associated with mammalian target of rapamycin signalling were detected in the PFC and with glutamatergic signalling in the hippocampus. Based on the proteomic and metabonomic findings, we were able to develop a schematic model summarizing the most prominent molecular network findings in the Df(16)A^+/- mouse. Interestingly, the implicated pathways can be linked to one of the most consistent and strongest proteomic candidates, (OGT1), which is a predicted miR-185 target. Our results provide novel insights into system-biological mechanisms associated with the 22q11DS, which may be linked to cognitive dysfunction and an increased risk to develop schizophrenia. Further investigation of these pathways could help to identify novel drug targets for the treatment of schizophrenia.

The Current Status of the Ketogenic Diet in Psychiatry

BACKGROUND

The ketogenic diet (KD) has been used in treatment-resistant epilepsy since the 1920s. It has been researched in a variety of neurological conditions in both animal models and human trials. The aim of this review is to clarify the potential role of KD in psychiatry.

METHODS

Narrative review of electronic databases PubMED, PsychINFO, and Scopus.

RESULTS

The search yielded 15 studies that related the use of KD in mental disorders including anxiety, depression, bipolar disorder, schizophrenia, autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD). These studies comprised nine animal models, four case studies, and two open-label studies in humans. In anxiety, exogenous ketone supplementation reduced anxiety-related behaviors in a rat model. In depression, KD significantly reduced depression-like behaviors in rat and mice models in two controlled studies. In bipolar disorder, one case study reported a reduction in symptomatology, while a second case study reported no improvement. In schizophrenia, an open-label study in female patients (n = 10) reported reduced symptoms after 2 weeks of KD, a single case study reported no improvement. In a brief report, 3 weeks of KD in a mouse model normalized pathological behaviors. In ASD, an open-label study in children (n = 30) reported no significant improvement; one case study reported a pronounced and sustained response to KD. In ASD, in four controlled animal studies, KD significantly reduced ASD-related behaviors in mice and rats. In ADHD, in one controlled trial of KD in dogs with comorbid epilepsy, both conditions significantly improved.

CONCLUSION

Despite its long history in neurology, the role of KD in mental disorders is unclear. Half of the published studies are based on animal models of mental disorders with limited generalizability to the analog conditions in humans. The review lists some major limitations including the lack of measuring ketone levels in four studies and the issue of compliance to the rigid diet in humans. Currently, there is insufficient evidence for the use of KD in mental disorders, and it is not a recommended treatment option. Future research should include long-term, prospective, randomized, placebo-controlled crossover dietary trials to examine the effect of KD in various mental disorders.

Brain-borne IL-1 adjusts glucoregulation and provides fuel support to astrocytes and neurons in an autocrine/paracrine manner

It is still controversial which mediators regulate energy provision to activated neural cells, as insulin does in peripheral tissues. Interleukin-1β (IL-1β) may mediate this effect as it can affect glucoregulation, it is overexpressed in the 'healthy' brain during increased neuronal activity, and it supports high-energy demanding processes such as long-term potentiation, memory and learning. Furthermore, the absence of sustained neuroendocrine and behavioral counterregulation suggests that brain glucose-sensing neurons do not perceive IL-1β-induced hypoglycemia. Here, we show that IL-1β adjusts glucoregulation by inducing its own production in the brain, and that IL-1β-induced hypoglycemia is myeloid differentiation primary response 88 protein (MyD88)-dependent and only partially counteracted by Kir6.2-mediated sensing signaling. Furthermore, we found that, opposite to insulin, IL-1β stimulates brain metabolism. This effect is absent in MyD88-deficient mice, which have neurobehavioral alterations associated to disorders in glucose homeostasis, as during several psychiatric diseases. IL-1β effects on brain metabolism are most likely maintained by IL-1β auto-induction and may reflect a compensatory increase in fuel supply to neural cells. We explore this possibility by directly blocking IL-1 receptors in neural cells. The results showed that, in an activity-dependent and paracrine/autocrine manner, endogenous IL-1 produced by neurons and astrocytes facilitates glucose uptake by these cells. This effect is exacerbated following glutamatergic stimulation and can be passively transferred between cell types. We conclude that the capacity of IL-1β to provide fuel to neural cells underlies its physiological effects on glucoregulation, synaptic plasticity, learning and memory. However, deregulation of IL-1β production could contribute to the alterations in brain glucose metabolism that are detected in several neurologic and psychiatric diseases.