Genetic predictors of risk and resilience in psychiatric disorders: a cross-disorder genome-wide association study of functional impairment in major depressive disorder, bipolar disorder, and schizophrenia

A German translation and validation of the sense of agency scale

Sense of agency refers to the experience of controlling one's actions and through them events in the outside world. General agency beliefs can be measured with the Sense of Agency Scale (SoAS), which consists of the sense of positive agency subscale (i.e., feeling of being in control over one's own body, mind, and environment) and the sense of negative agency subscale (i.e., feeling existentially helpless). The aim of the present study was to validate a German version of the SoAS. Using factor analyzes, we replicated the two-factor structure of the original version of the SoAS. Further, the German SoAS showed good model fits, good internal consistency, and moderate test-retest reliability. Construct validity was supported by significant low to moderate correlations of the German SoAS with other conceptually similar, but still distinct constructs such as general self-efficacy. Additionally, the German SoAS has an incremental value in explaining variance in the extent of subclinical symptoms of schizotypal personality disorder that goes beyond variance explained by constructs that are conceptually similar to sense of agency. Taken together, the results indicate that the German SoAS is a valid and suitable instrument to assess one's general agency beliefs.

Chondroitin Sulphate Proteoglycan Axonal Coats in the Human Mediodorsal Thalamic Nucleus

Mounting evidence supports a key involvement of the chondroitin sulfate proteoglycans (CSPGs) NG2 and brevican (BCAN) in the regulation of axonal functions, including axon guidance, fasciculation, conductance, and myelination. Prior work suggested the possibility that these functions may, at least in part, be carried out by specialized CSPG structures surrounding axons, termed axonal coats. However, their existence remains controversial. We tested the hypothesis that NG2 and BCAN, known to be associated with oligodendrocyte precursor cells, form axonal coats enveloping myelinated axons in the human brain. In tissue blocks containing the mediodorsal thalamic nucleus (MD) from healthy donors (n = 5), we used dual immunofluorescence, confocal microscopy, and unbiased stereology to characterize BCAN and NG2 immunoreactive (IR) axonal coats and measure the percentage of myelinated axons associated with them. In a subset of donors (n = 3), we used electron microscopy to analyze the spatial relationship between axons and NG2- and BCAN-IR axonal coats within the human MD. Our results show that a substantial percentage (∼64%) of large and medium myelinated axons in the human MD are surrounded by NG2- and BCAN-IR axonal coats. Electron microscopy studies show NG2- and BCAN-IR axonal coats are interleaved with myelin sheets, with larger axons displaying greater association with axonal coats. These findings represent the first characterization of NG2 and BCAN axonal coats in the human brain. The large percentage of axons surrounded by CSPG coats, and the role of CSPGs in axonal guidance, fasciculation, conductance, and myelination suggest that these structures may contribute to several key axonal properties.

Lack of association of FKBP5 SNPs and haplotypes with susceptibility and treatment response phenotypes in Han Chinese with major depressive disorder: A pilot case-control study (STROBE)

The identification of single-nucleotide polymorphisms (SNPs) in genes putatively related to pathophysiological processes in major depressive disorder (MDD) might improve both diagnosis and personalized treatment strategies eventually leading to more effective interventions. Considering the important role of the glucocorticoid receptor and the related FK506 binding protein 51 (FKBP51) in the pathophysiology of MDD, we aimed to investigate putative associations between variants of FKBP5, the coding gene of FKBP51, with antidepressant treatment resistance and MDD susceptibility.Nine common SNPs of the FKBP5 gene prioritized based on location and, putative or known functions were genotyped in Han Chinese population, including MDD patients with or without antidepressant-treatment resistance and healthy controls. Associations of FKBP5 SNPs with MDD susceptibility and treatment response were examined in the whole group of MDD patients, as well as in subgroups stratified by antidepressant treatment resistance, compared with healthy controls.In total, 181 Han Chinese patients with MDD and 80 healthy controls were recruited. No significant SNP or haplotype associations were observed in the whole patient group. There were nominal significant differences both for the haplotype block with SNPs in strong LD (r2 > 0.8, P = .040) and haplotype block with SNPs in moderate LD (r2 > 0.1, P = .017) between the haplotype distributions of patients with antidepressant treatment resistance (n = 81) and healthy controls, but both significances did not survive multiple testing correction. Furthermore, no specific haplotype could be observed causing a significant difference in any combination between all comparisons.No associations were observed of FKBP5 variants with MDD or antidepressant treatment response. The lack of associations might be due to the relatively small sample size of this study (power ranged from 0.100 to 0.752). A follow-up study will need larger, better phenotyped, and more homogeneous samples to draw a definitive conclusion regarding the involvement of this gene in MDD.

A comprehensive model of predictors of quality of life in older adults with schizophrenia: results from the CSA study

BACKGROUND

Numerous factors are known to influence quality of life of adults with schizophrenia. However, little is known regarding the potential predictors of quality of life in the increasing population of older adults with schizophrenia. The main objective of the present study was to propose a comprehensive model of quality of life in this specific population.

METHODS

Data were derived from the Cohort of individuals with Schizophrenia Aged 55 years or more (CSA) study, a large (N = 353) multicenter sample of older adults with schizophrenia or schizoaffective disorder recruited from French community mental-health teams. We used structural equation modeling to simultaneously examine the effects of six broad groups of clinical factors previously identified as potential predictors of quality of life in this population, including (1) severity of general psychopathology, (2) severity of depression, (3) severity of cognitive impairment, (4) psychotropic medications, (5) general medical conditions and (6) sociodemographic characteristics.

RESULTS

General psychopathology symptoms, and in particular negative and depressive symptoms, cognitive impairment, reduced overall functioning and low education were significantly and independently associated with diminished quality of life (all p < 0.05). Greater number of medical conditions and greater number of antipsychotics were also independently and negatively associated with quality of life, although these associations did not reach statistical significance in sensitivity analyses, possibly due to limited statistical power.

CONCLUSION

Several domains are implicated in quality of life among older adults with schizophrenia. Interventions targeting these factors may help improve importantly quality of life of this vulnerable population.

Variable Phenotypes of Epilepsy, Intellectual Disability, and Schizophrenia Caused by 12p13.33-p13.32 Terminal Microdeletion in a Korean Family: A Case Report and Literature Review

A simultaneous analysis of nucleotide changes and copy number variations (CNVs) based on exome sequencing data was demonstrated as a potential new first-tier diagnosis strategy for rare neuropsychiatric disorders. In this report, using depth-of-coverage analysis from exome sequencing data, we described variable phenotypes of epilepsy, intellectual disability (ID), and schizophrenia caused by 12p13.33–p13.32 terminal microdeletion in a Korean family. We hypothesized that CACNA1C and KDM5A genes of the six candidate genes located in this region were the best candidates for explaining epilepsy, ID, and schizophrenia and may be responsible for clinical features reported in cases with monosomy of the 12p13.33 subtelomeric region. On the background of microdeletion syndrome, which was described in clinical cases with mild, moderate, and severe neurodevelopmental manifestations as well as impairments, the clinician may determine whether the patient will end up with a more severe or milder end-phenotype, which in turn determines disease prognosis. In our case, the 12p13.33–p13.32 terminal microdeletion may explain the variable expressivity in the same family. However, further comprehensive studies with larger cohorts focusing on careful phenotyping across the lifespan are required to clearly elucidate the possible contribution of genetic modifiers and the environmental influence on the expressivity of 12p13.33 microdeletion and associated characteristics.

Resilience in severe mental disorders: correlations to clinical measures and quality of life in hospitalized patients with major depression, bipolar disorder, and schizophrenia

PURPOSE

To evaluate resilience in severe mental disorders and correlate it with clinical measures and quality of life.

METHODS

Resilience (Resilience Scale, RS) and quality of life (WHOQOL-BREF questionnaire) were prospectively evaluated in a sample of 384 hospitalized patients diagnosed with severe mental disorders (depression, bipolar disorder and schizophrenia). Clinical outcomes were measured using the Global Assessment of Functioning Scale (GAF), Clinical Global Impression (CGI), Cumulative Illness Rating Scale (CIRS), Hamilton Scale-Depression (HAM-D), Young Mania Rating Scale (YMRS), and Brief Psychiatric Rating Scale (BPRS).

RESULTS

Resilience measure showed a difference between the three clinical groups analyzed in the study, with lower scores in depressed patients than in bipolar disorder or schizophrenia patients. There was a trend toward a correlation between resilience and depressive symptoms (Hamilton Scale-Depression; P = 0.052; r_s = - 0.163). The scores in the resilience scale's personal competence domain presented a tendency of association with general psychiatric symptoms (Brief Psychiatric Rating Scale; P = 0.058; r = - 0.138). There was a significantly positive association between resilience and all domains of quality of life (r = 0.306-0.545; P < 0.05). Sociodemographic data like age, education, intelligence quotient, sex, and marital status were associated with resilience.

CONCLUSION

Depressive patients had low scores on the resilience scale compared to patients with other disorders. Resilience was positively associated with quality of life. Therefore, it deserves special attention, as it promotes more positive outcomes and improves patients' quality of life with severe mental disorders.

Molecular signature of extracellular matrix pathology in schizophrenia

Growing evidence points to a critical involvement of the extracellular matrix (ECM) in the pathophysiology of schizophrenia (SZ). Decreases of perineuronal nets (PNNs) and altered expression of chondroitin sulphate proteoglycans (CSPGs) in glial cells have been identified in several brain regions. GWAS data have identified several SZ vulnerability variants of genes encoding for ECM molecules. Given the potential relevance of ECM functions to the pathophysiology of this disorder, it is necessary to understand the extent of ECM changes across brain regions, their region- and sex-specificity and which ECM components contribute to these changes. We tested the hypothesis that the expression of genes encoding for ECM molecules may be broadly disrupted in SZ across several cortical and subcortical brain regions and include key ECM components as well as factors such as ECM posttranslational modifications and regulator factors. Gene expression profiling of 14 neocortical brain regions, caudate, putamen and hippocampus from control subjects (n = 14/region) and subjects with SZ (n = 16/region) was conducted using Affymetrix microarray analysis. Analysis across brain regions revealed widespread dysregulation of ECM gene expression in cortical and subcortical brain regions in SZ, impacting several ECM functional key components. SRGN, CD44, ADAMTS1, ADAM10, BCAN, NCAN and SEMA4G showed some of the most robust changes. Region-, sex- and age-specific gene expression patterns and correlation with cognitive scores were also detected. Taken together, these findings contribute to emerging evidence for large-scale ECM dysregulation in SZ and point to molecular pathways involved in PNN decreases, glial cell dysfunction and cognitive impairment in SZ.

Study of Functional Impairment in Students of Elementary and Secondary Public Schools in Iran

OBJECTIVE

The current study aimed to investigate the frequency of impairment in different functional domains of life and the relationship between sex and age and functional impairment in school-based samples of Iranian children and adolescents.

METHOD

A sample of 270 children (ages 6-11) enrolled in two public elementary schools and a sample of 386 adolescents (ages 12-17) enrolled in four public secondary schools were selected by multistage sampling. The Persian version of the parent report form and self-report form of the Weiss Functional Impairment Rating Scale (WFIRS-P and WFIRS-S) were used for evaluating functional impairment in children and adolescents, respectively. Two-way analyses of variance (two-way ANOVAs) were conducted to explore the main effects and the interaction effect of sex and age on functional impairment.

RESULTS

11.9% of children and 29.5% of adolescents showed impairment in at least two functional domains of life. The most frequent impaired domain was life skills (22.6% of children and 30.3% of adolescents). While no significant sex and age effect was found during childhood, male adolescents showed more impairment in externalizing domains and female adolescents showed more internalizing difficulties. In addition, older adolescents showed more functional impairment relative to younger adolescents.

CONCLUSIONS

Detailed knowledge of the relationship between sex and age and functional impairment could be a starting point to target the major psychosocial elements of these challenges.

Similarities in Cortical Transcriptome Alterations Between Schizophrenia and Bipolar Disorder Are Related to the Presence of Psychosis

Schizophrenia (SCZ) and bipolar disorder (BP) share a number of features. For example, multiple transcriptome analyses have reported molecular alterations common to both diagnoses, findings supported by the considerable overlap in the genetic risk for each disorder. These molecular similarities may underlie certain clinical features that are frequently present in both disorders. Indeed, many individuals with BP exhibit psychosis, and some individuals with SCZ have prominent mood symptoms that warrant the diagnosis of schizoaffective disorder (SA). To explore the potential relationships between molecular alterations and certain clinical features among subjects with these diagnoses, we analyzed RNA sequencing data from the dorsolateral prefrontal and anterior cingulate cortices, provided by the CommonMind Consortium, in subjects from the University of Pittsburgh Brain Tissue Donation Program. Relative to unaffected comparison subjects, in each brain region, robust differential gene expression was present only in SCZ, including a lower expression of genes involved in mitochondrial function and an elevated expression of immune-related genes. However, correlation analyses showed that BP subjects had similar, although less pronounced, gene expression alterations. Comparisons across subgroups of subjects revealed that the similarities between SCZ and BP subjects were principally due to the BP subjects with psychosis. Moreover, the gene expression profile in BP subjects with psychosis was more similar to "pure" SCZ and SA subjects than to BP subjects without psychosis. Together, these analyses suggest that similarities in gene expression between SCZ and BP are at least partially related to the presence of psychosis in some BP subjects.

Associations between the development of PTSD symptoms and longitudinal changes in the DNA methylome of deployed military servicemen: A comparison with polygenic risk scores

Objective

Method

Results

Conclusion

•

First study of methylation changes over a deployment period using three time-points.

•

Post-deployment methylation decreases in EP300 were associated with delayed onset PTSD.

•

Genetic risk was exclusively related to a non-delayed PTSD onset.

Psychiatric symptoms and quality of life in older adults with schizophrenia spectrum disorder: results from a multicenter study

The severity of psychopathology has a strong negative impact on quality of life (QoL) among older adults with schizophrenia spectrum disorder. However, because these subjects generally experience multiple psychiatric symptoms, it remains unclear whether decreased QoL in this population is due to specific symptoms (e.g., hallucinations), specific dimensions of psychopathology (e.g., negative symptoms), a general psychopathology dimension representing the shared effect across all psychiatric symptoms, or a combination of these explanations. Data were derived from the Cohort of individuals with Schizophrenia Aged 55 years or more (CSA) study, a large (N = 353) multicenter sample of older adults with schizophrenia spectrum disorder recruited from French public-sector psychiatric departments. We used structural equation modeling to examine the shared and specific effects of psychiatric symptoms on QoL, while adjusting for sociodemographic characteristics, general medical conditions, global cognitive functioning and psychotropic medications. Psychiatric symptoms and QoL were assessed face-to-face by psychiatrists using the Brief Psychiatric Rating Scale (BPRS) and the Quality of Life Scale (QLS). Among older adults with schizophrenia spectrum disorder, effects of psychiatric symptoms on QoL were exerted mostly through a general psychopathology dimension (β = - 0.43, p < 0.01). Negative symptom dimension had an additional negative effect on QoL beyond the effect of that factor (β = - 0.28, p < 0.01). Because psychiatric symptoms affect QoL mainly through two dimensions of psychopathology, i.e., a general psychopathology dimension and a negative symptom dimension, mechanisms underlying those dimensions should be considered as promising targets for therapeutic interventions to substantially improve quality of life of this vulnerable population.

Comparative Pathway Integrator: A Framework of Meta-Analytic Integration of Multiple Transcriptomic Studies for Consensual and Differential Pathway Analysis

Pathway enrichment analysis provides a knowledge-driven approach to interpret differentially expressed genes associated with disease status. Many tools have been developed to analyze a single study. However, when multiple studies of different conditions are jointly analyzed, novel integrative tools are needed. In addition, pathway redundancy introduced by combining multiple public pathway databases hinders interpretation and knowledge discovery. We present a meta-analytic integration tool, Comparative Pathway Integrator (CPI), to address these issues using adaptively weighted Fisher's method to discover consensual and differential enrichment patterns, a tight clustering algorithm to reduce pathway redundancy, and a text mining algorithm to assist interpretation of the pathway clusters. We applied CPI to jointly analyze six psychiatric disorder transcriptomic studies to demonstrate its effectiveness, and found functions confirmed by previous biological studies as well as novel enrichment patterns. CPI's R package is accessible online on Github metaOmics/MetaPath.

Using World Health Organization Disability Assessment Schedule 2.0 in people with schizophrenia: a 4-year follow-up

Little is known about the changes of people with schizophrenia disability in Taiwan who receive routine treatments under the current mental healthcare system. The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) was used to assess and track changes in the degree of disability in people with schizophrenia before and after 4 years of follow-up. Data on 4497 people with schizophrenia were acquired from the Taiwan Data Bank of Persons with Disability. The WHODAS 2.0 was used for disability assessment, and the chi-square test, logistic regression and generalised estimating equations were adopted for statistical analysis. People with schizophrenia exhibited improvement in cognition, mobility and participation among the six domains as well as in the overall score. The degree of disability in all domains remained mild to moderate among people aged 18-64 years; the degree of disability in cognition declined from moderate to severe among patients aged ≥65 years. The degree of disability in all domains remained mild to moderate among people with mild to moderate impairment; among those with severe impairment, the degree of disability in the domains of cognition and life activities declined from moderate to severe and the degree of disability in the domain of mobility declined from mild to moderate. Community-dwelling patients exhibited less degree of disability in all domains than their institutionalised peers. Early detection and treatment and an emphasis on communication and social problem-solving skills in rehabilitation programmes are recommended for people with schizophrenia.

The genetics of bipolar disorder

Bipolar disorder (BD) is one of the most heritable mental illnesses, but the elucidation of its genetic basis has proven to be a very challenging endeavor. Genome-Wide Association Studies (GWAS) have transformed our understanding of BD, providing the first reproducible evidence of specific genetic markers and a highly polygenic architecture that overlaps with that of schizophrenia, major depression, and other disorders. Individual GWAS markers appear to confer little risk, but common variants together account for about 25% of the heritability of BD. A few higher-risk associations have also been identified, such as a rare copy number variant on chromosome 16p11.2. Large scale next-generation sequencing studies are actively searching for other alleles that confer substantial risk. As our understanding of the genetics of BD improves, there is growing optimism that some clear biological pathways will emerge, providing a basis for future studies aimed at molecular diagnosis and novel therapeutics.

Genomics and psychological resilience: a research agenda

Although exposure to adversity increases risk for poor mental health outcomes, many people exposed to adversity do not develop such outcomes. Psychological resilience, defined broadly as positive emotional and/or behavioral adaptation to adversity, may be influenced by genetic factors that have remained largely unexplored in the era of large-scale genome-wide studies. In this perspective, we provide an integrative framework for studying human genome-wide variation underlying resilience. We first outline three complementary working definitions of psychological resilience-as a capacity, process, and outcome. For each definition, we review emerging empirical evidence, including findings from positive psychology, to illustrate how a resilience-based framework can guide novel and fruitful directions for the field of psychiatric genomics, distinct from the ongoing study of psychiatric risk and related traits. Finally, we provide practical recommendations for future genomic research on resilience, highlighting a need to augment cross-sectional findings with prospective designs that include detailed measurement of adversities and outcomes. A research framework that explicitly addresses resilience could help us to probe biological mechanisms of stress adaptation, identify individuals who may benefit the most from prevention and early intervention, and ascertain modifiable protective factors that mitigate negative outcomes even for those at high genetic risk.

Conceptualizing resilience in adult mental health literature: A systematic review and narrative synthesis

PURPOSE

This review aims to identify how the term 'resilience' is conceptualized across adult mental health research due to ongoing criticism regarding the lack of consistency in its conceptualization.

METHOD

A systematic search, including hand searches of book chapters, was conducted using search terms ('resilien*') AND ('mental illness' OR 'mental health problem'). Papers were excluded if they did not meet the following criteria: written in English, provide a clear conceptualization of resilience, include only adults (aged 18 + ) in the sample, solely focus on individuals with a primary diagnosis of mental illness, and peer-reviewed. Data were extracted on conceptualizations of resilience, demographic, and diagnostic variables of the study population, publication year, and the research design used. Conceptualizations were combined and collapsed into overarching themes and then refined through joint discussion, consultation with a third reviewer, and input from a larger multidisciplinary team.

RESULTS

Thirty-one texts (6 book chapters, 4 reviews, 2 appraisals/critical evaluations, 1 editorial, and 18 research projects) were included. Two broad understandings of resilience were identified: resilience as a process and resilience as a characteristic of an individual. Processes comprise three themes: 'immunity', 'bouncing back', and 'growth', whilst characteristics are captured in two themes 'personal resources' and 'social resources'.

CONCLUSIONS

These findings suggest that resilience can be conceptualized in a clear and meaningful manner in adult mental health research. The five themes reflect distinct ways of using the term resilience. Whilst each one of them may have merit in future research, it appears beneficial to make clear in research which exact conceptualization of resilience has been adopted.

PRACTITIONER POINTS

When considering and reading about 'resilience', one should be aware that there are different concepts of it. The main difference is between resilience as a personal characteristic and resilience as a process. Therapy may address resilience as a personal characteristic by utilizing individual and social resources. The therapeutic process may be understood as resilience in form of bouncing back and personal growth.

Shared preventive factors associated with relapse after a response to electroconvulsive therapy in four major psychiatric disorders

AIM

The efficacy of electroconvulsive therapy (ECT) has been established in psychiatric disorders but the high rate of relapse is a critical problem. The current study sought preventative factors associated with relapse after a response to ECT in a continuum of four major psychiatric disorders.

METHODS

The records of 255 patients with four psychiatric disorders (83 unipolar depression, 60 bipolar depression, 91 schizophrenia, 21 schizoaffective disorder) were retrospectively reviewed.

RESULTS

The relapse-free rate of all patients at 1 year was 56.3% in the four psychiatric disorders without a difference. As a result of univariate analysis, three items could be considered as preventative factors associated with relapse: a small number of psychiatric symptom episodes before an acute course of ECT, the use of mood stabilizers, and the use of maintenance ECT. Multivariate analysis was performed, keeping age, sex, and diagnosis constant in addition to the three items, and small number of psychiatric symptom episodes before an acute course of ECT (P = 0.003), the use of lithium (P = 0.025), the use of valproate (P = 0.027), and the use of maintenance ECT (P = 0.001) were found to be significant preventative measures against relapse.

CONCLUSION

The use of mood stabilizers, such as lithium and valproate, and maintenance ECT could be shared preventive factors associated with relapse after a response to ECT in four major psychiatric disorders.

ADAMTS proteins in human disorders

ADAMTS proteins are a superfamily of 26 secreted molecules comprising two related, but distinct families. ADAMTS proteases are zinc metalloendopeptidases, most of whose substrates are extracellular matrix (ECM) components, whereas ADAMTS-like proteins lack a metalloprotease domain, reside in the ECM and have regulatory roles vis-à-vis ECM assembly and/or ADAMTS activity. Evolutionary conservation and expansion of ADAMTS proteins in mammals is suggestive of crucial embryologic or physiological roles in humans. Indeed, Mendelian disorders or birth defects resulting from naturally occurring ADAMTS2, ADAMTS3, ADAMTS10, ADAMTS13, ADAMTS17, ADAMTS20, ADAMTSL2 and ADAMTSL4 mutations as well as numerous phenotypes identified in genetically engineered mice have revealed ADAMTS participation in major biological pathways. Important roles have been identified in a few acquired conditions. ADAMTS5 is unequivocally implicated in pathogenesis of osteoarthritis via degradation of aggrecan, a major structural proteoglycan in cartilage. ADAMTS7 is strongly associated with coronary artery disease and promotes atherosclerosis. Autoantibodies to ADAMTS13 lead to a platelet coagulopathy, thrombotic thrombocytopenic purpura, which is similar to that resulting from ADAMTS13 mutations. ADAMTS proteins have numerous potential connections to other human disorders that were identified by genome-wide association studies. Here, we review inherited and acquired human disorders in which ADAMTS proteins participate, and discuss progress and prospects in therapeutics.

Novel gene-brain structure relationships in psychotic disorder revealed using parallel independent component analyses

BACKGROUND

Schizophrenia, schizoaffective disorder, and psychotic bipolar disorder overlap with regard to symptoms, structural and functional brain abnormalities, and genetic risk factors. Neurobiological pathways connecting genes to clinical phenotypes across the spectrum from schizophrenia to psychotic bipolar disorder remain largely unknown.

METHODS

We examined the relationship between structural brain changes and risk alleles across the psychosis spectrum in the multi-site Bipolar-Schizophrenia Network for Intermediate Phenotypes (B-SNIP) cohort. Regional MRI brain volumes were examined in 389 subjects with a psychotic disorder (139 schizophrenia, 90 schizoaffective disorder, and 160 psychotic bipolar disorder) and 123 healthy controls. 451,701 single-nucleotide polymorphisms were screened and processed using parallel independent component analysis (para-ICA) to assess associations between genes and structural brain abnormalities in probands.

RESULTS

482 subjects were included after quality control (364 individuals with psychotic disorder and 118 healthy controls). Para-ICA identified four genetic components including several risk genes already known to contribute to schizophrenia and bipolar disorder and revealed three structural components that showed overlapping relationships with the disease risk genes across the three psychotic disorders. Functional ontologies representing these gene clusters included physiological pathways involved in brain development, synaptic transmission, and ion channel activity.

CONCLUSIONS

Heritable brain structural findings such as reduced cortical thickness and surface area in probands across the psychosis spectrum were associated with somewhat distinct genes related to putative disease pathways implicated in psychotic disorders. This suggests that brain structural alterations might represent discrete psychosis intermediate phenotypes along common neurobiological pathways underlying disease expression across the psychosis spectrum.

microRNA-137 promotes apoptosis in ovarian cancer cells via the regulation of XIAP

Background:

microRNAs (miRNAs) have regulatory roles in various cellular processes, including apoptosis. Recently, X-linked inhibitor of apoptosis protein (XIAP) has been reported to be dysregulated in epithelial ovarian cancer (EOC). However, the mechanism underlying this dysregulation is largely unknown.

Methods:

Using bioinformatics and a literature analysis, a panel of miRNAs dysregulated in EOC was chosen for further experimental confirmation from hundreds of miRNAs that were predicted to interact with the XIAP 3′UTR. A dual-luciferase reporter assay was employed to detect the interaction by cellular co-transfection of an miRNA expression vector and a reporter vector with the XIAP 3′UTR fused to a Renilla luciferase reporter. DAPI and TUNEL approaches were used to further determine the effects of an miR-137 mimic and inhibitor on cisplatin-induced apoptosis in ovarian cancer cells.

Results:

We identified eight miRNAs by screening a panel of dysregulated miRNAs that may target the XIAP 3′UTR. The strongest inhibitory miRNA, miR-137, suppressed the activity of a luciferase reporter gene fused with the XIAP 3′UTR and decreased the levels of XIAP protein in SKOV3 ovarian cancer cells. Furthermore, forced expression of miR-137 increased cisplatin-induced apoptosis, and the depressed expression of miR-137 decreased cisplatin-induced apoptosis in SKOV3 and primary EOC cells. Consistently, the disruption of miR-137 via CRISPR/Cas9 inhibited apoptosis and upregulated XIAP in A2780 cells. Furthermore, the effect of miR-137 on apoptosis could be rescued by XIAP in SKOV3 cells. In addition, miR-137 expression is inversely correlated with the level of XIAP protein in both ovarian cancer tissues and cell lines.

Conclusions:

Our data suggest that multiple miRNAs can regulate XIAP via its 3′UTR. miR-137 can sensitise ovarian cancer cells to cisplatin-induced apoptosis, providing new insight into overcoming drug resistance in ovarian cancer.

Comparison of 16S and COX1 genes mitochondrial regions and their usefulness for genetic analysis of ticks (Acari: Ixodidae)

INTRODUCTION

In recent decades the analysis of mitochondrial genes has been used for population and phylogenetic studies of ticks allowing many advances in their systematics. Mitochondrial ribosomal 16S (16S) subunit is one of the most frequently used among those genes available for tick analysis, whereas cytochrome oxidase gene 1 (COX1) has recently been used and proposed as an alternative to the traditional 16S gene marker. 

OBJECTIVE

To evaluate the usefulness of 16S and COX1 in genetic studies of ticks by analyzing sequences of three species commonly found in the Caribbean region of Colombia. 

RESULTS

The analysis of both genes sequences allowed us to identify the three species with high levels of confidence and interspecific genetic divergence (19-22%), although only COX1 allowed us to detect intraspecific genetic variability (up to ~0.8%). A substitution saturation analysis indicated that the 16S gene was not saturated with transitions while the COX1 gene showed saturation distances starting at ~17%. 

CONCLUSION

Our results indicated that the 16S gene seems to have better features for interspecific phylogenetic analyses because of its high level of genetic divergence and low saturation pattern, while the COX1 gene appears to be more useful for intraspecific genetic variability studies. However, as our study was conducted at a local scale, future studies at different biogeographical scales would help to establish its usefulness in wider and more complex scenarios.

In Sickness and in Health: Perineuronal Nets and Synaptic Plasticity in Psychiatric Disorders

Rapidly emerging evidence implicates perineuronal nets (PNNs) and extracellular matrix (ECM) molecules that compose or interact with PNNs, in the pathophysiology of several psychiatric disorders. Studies on schizophrenia, autism spectrum disorders, mood disorders, Alzheimer's disease, and epilepsy point to the involvement of ECM molecules such as chondroitin sulfate proteoglycans, Reelin, and matrix metalloproteases, as well as their cell surface receptors. In many of these disorders, PNN abnormalities have also been reported. In the context of the “quadripartite” synapse concept, that is, the functional unit composed of the pre- and postsynaptic terminals, glial processes, and ECM, and of the role that PNNs and ECM molecules play in regulating synaptic functions and plasticity, these findings resonate with one of the most well-replicated aspects of the pathology of psychiatric disorders, that is, synaptic abnormalities. Here we review the evidence for PNN/ECM-related pathology in these disorders, with particular emphasis on schizophrenia, and discuss the hypothesis that such pathology may significantly contribute to synaptic dysfunction.

Prediction of treatment outcomes in psychiatry--where do we stand ?

Psychiatric treatment relies on a solid armamentarium of pharmacologic and nonpharmacologic treatment modalities that perform reasonably well for many patients but leave others in a state of chronic disability or troubled by problematic side effects. Treatment planning in psychiatry remains an art that depends on considerable trial and error. Thus, there is an urgent need for better tools that will provide a means for matching individual patients with the most effective treatments while minimizing the risk of adverse events. This review will consider the current state of the science in predicting treatment outcomes in psychiatry. Genetic and other biomarkers will be considered alongside clinical diagnostic, and family history data. Problems inherent in prediction medicine will also be discussed, along with recent developments that support the hope that psychiatry can do a better job in quickly identifying the best treatments for each patient.

Losing the sugar coating: potential impact of perineuronal net abnormalities on interneurons in schizophrenia

Perineuronal nets (PNNs) were shown to be markedly altered in subjects with schizophrenia. In particular, decreases of PNNs have been detected in the amygdala, entorhinal cortex and prefrontal cortex. The formation of these specialized extracellular matrix (ECM) aggregates during postnatal development, their functions, and association with distinct populations of GABAergic interneurons, bear great relevance to the pathophysiology of schizophrenia. PNNs gradually mature in an experience-dependent manner during late stages of postnatal development, overlapping with the prodromal period/age of onset of schizophrenia. Throughout adulthood, PNNs regulate neuronal properties, including synaptic remodeling, cell membrane compartmentalization and subsequent regulation of glutamate receptors and calcium channels, and susceptibility to oxidative stress. With the present paper, we discuss evidence for PNN abnormalities in schizophrenia, the potential functional impact of such abnormalities on inhibitory circuits and, in turn, cognitive and emotion processing. We integrate these considerations with results from recent genetic studies showing genetic susceptibility for schizophrenia associated with genes encoding for PNN components, matrix-regulating molecules and immune system factors. Notably, the composition of PNNs is regulated dynamically in response to factors such as fear, reward, stress, and immune response. This regulation occurs through families of matrix metalloproteinases that cleave ECM components, altering their functions and affecting plasticity. Several metalloproteinases have been proposed as vulnerability factors for schizophrenia. We speculate that the physiological process of PNN remodeling may be disrupted in schizophrenia as a result of interactions between matrix remodeling processes and immune system dysregulation. In turn, these mechanisms may contribute to the dysfunction of GABAergic neurons.

Genetic variants within the serotonin transporter associated with familial risk for major depression

The role of the serotonin transporter promoter linked polymorphism (5HTTLPR) in depression, despite much research, remains unclear. Most studies compare persons with and without depression to each other. We show offspring at high (N = 192) as compared to low (N = 101) familial risk for major depressive disorder were almost four times as likely to have two copies of the short allele at 5HTTLPR, suggesting that incorporation of family history could be helpful in identifying genetic differences.

Differential activation of immune factors in neurons and glia contribute to individual differences in resilience/vulnerability to sleep disruption

Individuals frequently find themselves confronted with a variety of challenges that threaten their wellbeing. While some individuals face these challenges efficiently and thrive (resilient) others are unable to cope and may suffer persistent consequences (vulnerable). Resilience/vulnerability to sleep disruption may contribute to the vulnerability of individuals exposed to challenging conditions. With that in mind we exploited individual differences in a fly's ability to form short-term memory (STM) following 3 different types of sleep disruption to identify the underlying genes. Our analysis showed that in each category of flies examined, there are individuals that form STM in the face of sleep loss (resilient) while other individuals show dramatic declines in cognitive behavior (vulnerable). Molecular genetic studies revealed that Antimicrobial Peptides, factors important for innate immunity, were candidates for conferring resilience/vulnerability to sleep deprivation. Specifically, Metchnikowin (Mtk), drosocin (dro) and Attacin (Att) transcript levels seemed to be differentially increased by sleep deprivation in glia (Mtk), neurons (dro) or primarily in the head fat body (Att). Follow-up genetic studies confirmed that expressing Mtk in glia but not neurons, and expressing dro in neurons but not glia, disrupted memory while modulating sleep in opposite directions. These data indicate that various factors within glia or neurons can contribute to individual differences in resilience/vulnerability to sleep deprivation.

Functional outcome in major psychiatric disorders and associated clinical and psychosocial variables: A potential cross-diagnostic phenotype for further genetic investigations?

OBJECTIVES

Functional outcome has recently become of interest for cross-diagnostic subphenotype approaches in psychiatric genetics. Therefore, it is crucial to know about clinical, demographic and psychosocial variables that correlate with long-term functioning. Unfortunately, there is a lack of studies that directly compare the importance of correlates for functional outcome between different disorders.

METHODS

Applying regression models to samples of patients with schizophrenia (SZ, n = 238), bipolar disorder (BD, n = 533) and major depressive disorder (MDD, n = 398), we compared the magnitude of association of potential correlates with functional outcome, measured by the Global Assessment of Functioning (GAF) score.

RESULTS

Shared correlates for worse functional outcome were poor premorbid functioning, insidious illness onset and poor premorbid work or social adjustment in all three disorders, and negative symptomatology in SZ and BD. Disorder-specific correlates for SZ were longer duration of illness, lower functioning during episodes and being life-time single, for BD substance abuse and suicidality, and for MDD premorbid unemployment and having a premorbid personality disorder.

CONCLUSIONS

We found different patterns of correlates for long-term functioning in SZ, BD and MDD. Knowledge of these patterns may improve the quality of genetic investigations focussing on functional outcome.

Prediction of treatment outcomes in psychiatry--where do we stand ?

Psychiatric treatment relies on a solid armamentarium of pharmacologic and nonpharmacologic treatment modalities that perform reasonably well for many patients but leave others in a state of chronic disability or troubled by problematic side effects. Treatment planning in psychiatry remains an art that depends on considerable trial and error. Thus, there is an urgent need for better tools that will provide a means for matching individual patients with the most effective treatments while minimizing the risk of adverse events. This review will consider the current state of the science in predicting treatment outcomes in psychiatry. Genetic and other biomarkers will be considered alongside clinical diagnostic, and family history data. Problems inherent in prediction medicine will also be discussed, along with recent developments that support the hope that psychiatry can do a better job in quickly identifying the best treatments for each patient.

Cryptorchidism and infertility in rats with targeted disruption of the Adamts16 locus

A Disintegrin And Metalloproteinase with ThromboSpondin motifs16 (ADAMTS-16) is a member of a family of metalloproteinases. Using a novel zinc-finger nuclease based gene-edited rat model harboring a targeted mutation of the Adamts16 locus, we previously reported this gene to be linked to blood pressure regulation. Here we document our observation with this model that Adamts16 is essential for normal development of the testis. Absence of Adamts16 in the homozygous Adamts16^mutant males resulted in cryptorchidism and male sterility. Heterozygous Adamts16^mutant males were normal, indicating that this is a recessive trait. Testes of homozygous Adamts16^mutant males were significantly smaller with significant histological changes associated with the lack of sperm production. Temporal histological assessments of the testis demonstrated that the seminiferous tubules did not support active spermatogenesis, but progressively lost germ cells, accumulated vacuoles and did not have any sperm. These observations, taken together with our previous report of renal abnormalities observed with the same Adamts16^mutant rats, suggest an important mechanistic link between Adamts16 and the functioning of the male genitourinary system.