Interferon signaling and hypercytokinemia-related gene expression in the blood of antidepressant non-responders.

genes identified in the training set yielded 85% discrimination accuracy for antidepressant responsiveness in the 34 test samples. Pathway analysis of the RNA sequencing data for antidepressant responsiveness identified that hypercytokinemia- and interferon-related genes were increased in non-responders. Disease and biofunction analysis identified changes in genes related to inflammatory and infectious diseases, including coronavirus disease. These results strongly suggest an association between antidepressant responsiveness and inflammation, which may be useful for future treatment strategies for depression.

Only 50% of patients with depression respond to the first antidepressant drug administered. Thus, biomarkers for prediction of antidepressant responses are needed, as predicting which patients will not respond to antidepressants can optimize selection of alternative therapies. We aimed to identify biomarkers that could predict antidepressant responsiveness using a novel data-driven approach based on statistical pattern recognition. We retrospectively divided patients with major depressive disorder into antidepressant responder and non-responder groups. Comprehensive gene expression analysis was performed using peripheral blood without narrowing the genes. We designed a classifier according to our own discrete Bayes decision rule that can handle categorical data. Nineteen genes showed differential expression in the antidepressant non-responder group (n = 15) compared to the antidepressant responder group (n = 15). In the training sample of 30 individuals, eight candidate genes had significantly altered expression according to quantitative real-time polymerase chain reaction. The expression of these genes was examined in an independent test sample of antidepressant responders (n = 22) and non-responders (n = 12). Using the discrete Bayes classifier with the


Metabolomic alterations in the blood plasma of older adults with mild cognitive impairment and Alzheimer's disease (from the Nakayama Study).

Alzheimer's disease (AD) is a progressive disease, and the number of AD patients is increasing every year as the population ages. One of the pathophysiological mechanisms of AD is thought to be the effect of metabolomic abnormalities. There have been several studies of metabolomic abnormalities of AD, and new biomarkers are being investigated. Metabolomic studies have been attracting attention, and the aim of this study was to identify metabolomic biomarkers associated with AD and mild cognitive impairment (MCI). Of the 927 participants in the Nakayama Study conducted in Iyo City, Ehime Prefecture, 106 were selected for this study as Control (n = 40), MCI (n = 26), and AD (n = 40) groups, matched by age and sex. Metabolomic comparisons were made across the three groups. Then, correlations between metabolites and clinical symptoms were examined. The blood mRNA levels of the ornithine metabolic enzymes were also measured. Of the plasma metabolites, significant differences were found in ornithine, uracil, and lysine. Ornithine was significantly decreased in the AD group compared to the Control and MCI groups (Control vs. AD: 97.2 vs. 77.4; P = 0.01, MCI vs. AD: 92.5 vs. 77.4; P = 0.02). Uracil and lysine were also significantly decreased in the AD group compared to the Control group (uracil, Control vs. AD: 272 vs. 235; P = 0.04, lysine, Control vs. AD: 208 vs. 176; P = 0.03). In the total sample, the MMSE score was significantly correlated with lysine, ornithine, thymine, and uracil. The Barthel index score was significantly correlated with lysine. The instrumental activities of daily living (IADL) score were significantly correlated with lysine, betaine, creatine, and thymine. In the ornithine metabolism pathway, the spermine synthase mRNA level was significantly decreased in AD. Ornithine was decreased, and mRNA expressions related to its metabolism were changed in the AD group compared to the Control and MCI groups, suggesting an association between abnormal ornithine metabolism and AD. Increased betaine and decreased methionine may also have the potential to serve as markers of higher IADL in elderly persons. Plasma metabolites may be useful for predicting the progression of AD.


免疫療法が著効し，髄液中の抗グルタミン酸受容体抗体が陽性であった小児自己免疫性溶連菌感染関連性精神神経障害が疑われた1例


Left DLPFC activity is associated with plasma kynurenine levels and can predict treatment response to escitalopram in major depressive disorder.

Decreased resting-state regional activity of the left DLPFC and decreased plasma kynurenine levels may predict treatment response to escitalopram, suggesting that it may be involved in the pathophysiology of major depressive disorder in response to escitalopram treatment.

Blood metabolite levels and resting-state brain activity were measured in patients with moderate to severe depression (n = 65) before and after 6-8 weeks of treatment with escitalopram, and these were compared between Responders and Nonresponders to treatment. We then examined the relationship between blood metabolites and brain activity related to treatment responsiveness in patients and healthy controls (n = 36).


Optimized protocol for the extraction of RNA and DNA from frozen whole blood sample stored in a single EDTA tube.

Cryopreservation of whole blood is useful for DNA collection, and clinical and basic research. Blood samples in ethylenediaminetetraacetic acid disodium salt (EDTA) tubes stored at - 80 °C are suitable for DNA extraction, but not for high-quality RNA extraction. Herein, a new methodology for high-quality RNA extraction from human blood samples is described. Quickly thawing frozen whole blood on aluminum blocks at room temperature could minimize RNA degradation, and improve RNA yield and quality compared with thawing the samples in a 37 °C water bath. Furthermore, the use of the NucleoSpin RNA kit increased RNA yield by fivefold compared with the PAXgene Blood RNA Kit. Thawing blood samples on aluminum blocks significantly increased the DNA yield by ~ 20% compared with thawing in a 37 °C water bath or on ice. Moreover, by thawing on aluminum blocks and using the NucleoSpin RNA and QIAamp DNA Blood kits, the extraction of RNA and DNA of sufficient quality and quantity was achieved from frozen EDTA whole blood samples that were stored for up to 8.5 years. Thus, extracting RNA from frozen whole blood in EDTA tubes after long-term storage is feasible. These findings may help advance gene expression analysis, as well as biomarker research for various diseases.


Role of an Atypical Cadherin Gene, Cdh23 in Prepulse Inhibition, and Implication of CDH23 in Schizophrenia.

We previously identified quantitative trait loci (QTL) for prepulse inhibition (PPI), an endophenotype of schizophrenia, on mouse chromosome 10 and reported Fabp7 as a candidate gene from an analysis of F2 mice from inbred strains with high (C57BL/6N; B6) and low (C3H/HeN; C3H) PPI levels. Here, we reanalyzed the previously reported QTLs with increased marker density. The highest logarithm of odds score (26.66) peaked at a synonymous coding and splice-site variant, c.753G>A (rs257098870), in the Cdh23 gene on chromosome 10; the c.753G (C3H) allele showed a PPI-lowering effect. Bayesian multiple QTL mapping also supported the same variant with a posterior probability of 1. Thus, we engineered the c.753G (C3H) allele into the B6 genetic background, which led to dampened PPI. We also revealed an e-QTL (expression QTL) effect imparted by the c.753G>A variant for the Cdh23 expression in the brain. In a human study, a homologous variant (c.753G>A; rs769896655) in CDH23 showed a nominally significant enrichment in individuals with schizophrenia. We also identified multiple potentially deleterious CDH23 variants in individuals with schizophrenia. Collectively, the present study reveals a PPI-regulating Cdh23 variant and a possible contribution of CDH23 to schizophrenia susceptibility.


An attempt to analyze the longitudinal psychological state of cancer patients in the active treatment stage.

The psychological state and changes over time of cancer patients in the active treatment stage were classified into emotions by the speech and behavior of the patient described in the medical record article of the cancer psychological interview record, and the analysis of the "emotional state map" was attempted. In all cases, positive / negative emotions were mixed and appeared with variation, but a relatively large number of positive emotions, including <joy>, <relief>, and <liking>, were manifested, and the same was true in patients who experienced stressful treatment events. In the background, the existence of appropriate support from medical professionals and psychological characteristics peculiar to the stage of active treatment was inferred, such as the active treatment of the target patient, the hospitalization environment in which mental and physical pain promptly appealed to medical professionals, and the influence of psychological interviews. Cancer patients during active treatment perceived and expressed changes in the body and pain caused by the disease, and after responses from medical professionals and family members, they were conscious of their physical condition and emotions. It is suggested that this analysis method helps to objectively understand and explain the invisible and ever-changing psychological state of cancer patients in the active treatment stage. J. Med. Invest. 68 : 148-153, February, 2021.

The Journal of Medical Investigation : JMI


Peritraumatic reactions, PTSD symptoms, and pain : A study of train disasters in Japan.

Objective : The purpose of this study was to examine the relationship between peritraumatic reactions, posttraumatic stress disorder (PTSD) symptoms, and pain in people injured in train disasters. Methods : The participants were injured in a train crash in Japan that left more than 100 dead. There were 218 participants in the analysis, with a mean age of 37.50 ± 14.67 years. Peritraumatic reactions were assessed using the Peritraumatic Distress Inventory. PTSD symptoms were evaluated using the Impact of Event Scale-Revised Japanese-language version. Pain was measured using the Visual Analog Scale. Results : Peritraumatic reactions did not directly affect PTSD symptoms but were found to be associated via latent variables. Regarding pain and PTSD symptoms, intrusive memories were more associated with pain than other symptoms were. There was an associative path from intrusion to pain, but no such path from pain to intrusion. Conclusions : Our results suggest that a therapeutic approach to intrusion may be effective in ameliorating the pain caused by injury. Future research should examine integrated treatment approaches for both PTSD and pain, rather than just for aspects of PTSD. J. Med. Invest. 68 : 85-89, February, 2021.


Association between serum folate levels and schizophrenia based on sex.

Our findings suggest that: (i) a low serum folate level may be associated with schizophrenia regardless of sex; and (ii) folate administration may be beneficial for the treatment of schizophrenia. In schizophrenic patients with low serum folate levels, folate administration might result in improvements in high tHcy and an increase in low vitamin B6 levels.


Metacognitive training for depression to elderly woman with depression : A case report

抑うつ症状を呈した高齢女性に対してうつ病のためのメタ認知トレーニングを実施した症例

Japanese Journal of Psychiatric Treatment


Decelerated epigenetic aging associated with mood stabilizers in the blood of patients with bipolar disorder.

There is high mortality among patients with bipolar disorder (BD). Studies have reported accelerated biological aging in patients with BD. Recently, Horvath and Hannum et al. independently developed DNA methylation (DNAm) profiles as "epigenetic clocks," which are the most accurate biological age estimate. This led to the development of two accomplished measures of epigenetic age acceleration (EAA) using blood samples, namely, intrinsic and extrinsic EAA (IEAA and EEAA, respectively). IEAA, which is based on Horvath's clock, is independent of blood cell counts and indicates cell-intrinsic aging. On the other hand, EEAA, which is based on Hannum's clock, is associated with age-dependent changes in blood cell counts and indicates immune system aging. Further, Lu et al. developed the "GrimAge" clock, which can strongly predict the mortality risk, and DNAm-based telomere length (DNAmTL). We used a DNAm dataset from whole blood samples obtained from 30 patients with BD and 30 healthy controls. We investigated Horvath EAA, IEAA, Hannum EAA, EEAA, Grim EAA, DNAmTL, and DNAm-based blood cell composition. Compared with controls, there was a decrease in Horvath EAA and IEAA in patients with BD. Further, there was a significant decrease in Horvath EAA and IEAA in patients with BD taking medication combinations of mood stabilizers (including lithium carbonate, sodium valproate, and carbamazepine) than in those taking no medication/monotherapy. This study provides novel evidence indicating decelerated epigenetic aging associated with mood stabilizers in patients with BD.


Structural variation in the glycogen synthase kinase 3β and brain-derived neurotrophic factor genes in Japanese patients with bipolar disorders.

Lithium is the first-line drug for the treatment of bipolar disorders (BDs); however, not all patients responded. Glycogen synthase kinase (GSK) 3β and brain-derived neurotrophic factor (BDNF) play a role in the therapeutic action of lithium. Since structural variations were reported in these genes, it is possible that these genomic variations may be involved in the therapeutic responses to lithium. Fifty patients with BDs and 50 healthy subjects (mean age 55.0 ± 15.0 years; M/F 19/31) participated. We examined structural variation of the GSK3β and BDNF genes by real-time PCR. We examined the influence of structural variation of these genes on the therapeutic responses to lithium and the occurrence of antidepressant-emergent affective switch (AEAS). The efficacy of lithium was assessed using the Alda scale, and AEAS was evaluated using Young Mania Rating Scale. Although we examined structural variations within intron II and VII of the GSK3 gene and from the end of exon IV to intron IV and within exon IX of the BDNF gene, no structural variation was found in BDs. Whereas 5 of 50 patients exhibited three copies of the genomic region within exon IV of the BDNF gene, all healthy subjects had two copies. No difference in the therapeutic efficacy of lithium was found between patients with three and two copies. No difference in the occurrence of AEAS was found between the two groups. The amplification of the BDNF gene influenced neither the therapeutic responses to lithium nor the occurrence of AEAS.


Predictors of life skills in people with schizophrenia

Objective : The purpose of the present study is to examine clinical factors related to life skills in people with schizophrenia. Method : The participants were 51 stabilized outpatients with schizophrenia. Their mean age was 38.91 (SD = 10.73) years. Life skills were assessed using the Life skills profile (LSP). Cognitive function was evaluated with the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB). Clinical symptoms were assessed using the Positive and Negative Syndrome scale (PANSS), the Calgary Depression Scale for Schizophrenia (CDSS) and the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS). Results : Cognitive function was not correlated with the LSP scores at all. Among clinical symptoms, scores of the PANSS positive and negative syndrome scales, the CDSS, and the DIEPSS had negative correlations with the LSP total score and the subscales. Stepwise regression analyses showed that the CDSS and PANSS negative syndrome scale scores were independent predictors of the LSP total score and two of the subscales. Conclusions : These results indicate that cognitive function is not associated with life skills but clinical symptoms such as depressive and negative symptoms have considerable impacts on life skills in people with schizophrenia. J. Med. Invest. 67 : 75-82, February, 2020.


ABCA7 Gene Expression and Genetic Association Study in Schizophrenia.

Although ATP-binding cassette sub-family A member 7 gene () is known to be associated with Alzheimer's disease, the relationship between and schizophrenia has been unknown. Schizophrenia patients (n = 50; 24 males, 62.1 ± 0.50 years old) and age- and sex-matched healthy controls (n = 50) were recruited for the mRNA analysis. Additionally, a case-control study for the rs3764650 genotypes was performed with 1308 samples (control subjects; n = 527, schizophrenia patients; n = 781). All participants were Japanese, unrelated to each other, and living in the same area. The distributions of the rs3764650 genotypes in schizophrenia patients were not different from that of controls. However, the mRNA expression levels in schizophrenia patients were significantly higher than those in controls by a logistic regression analysis. Additionally, the mRNA expression levels in schizophrenia patients were correlated with the rs3764650 genotypes in a dose-dependent manner. The mRNA expression levels in peripheral blood with the rs3764650 genotypes may be related to pathological mechanisms in schizophrenia and may be a biological marker for schizophrenia.


Plasma levels of matrix metalloproteinase-9 (MMP-9) are associated with cognitive performance in patients with schizophrenia.

Matrix metalloproteinase-9 (MMP-9) has been shown to modulate synaptic plasticity and may contribute to the pathophysiology of schizophrenia. This study investigated the peripheral levels of MMP-9 and its association with cognitive functions in patients with schizophrenia to see the possible involvement of MMP-9 in pathophysiology of schizophrenia, especially in cognitive decline. We measured the plasma levels of MMP-9 in 257 healthy controls and 249 patients with schizophrenia, including antipsychotic drug-free patients. We also explored the possible association between plasma MMP-9 levels and cognitive performance in healthy controls and patients with schizophrenia using the Wechsler Adult Intelligence Scale, Third Edition (WAIS- III), the Wechsler Memory Scale-Revised (WMS-R), and the Rey Auditory Verbal Learning Test (AVLT). We found that the plasma levels of MMP-9 were significantly higher in patients with schizophrenia, including antipsychotic drug-free patients, than in healthy controls. We found a significant negative association between plasma MMP-9 levels and cognitive performance in controls and patients with schizophrenia. Together, these convergent data suggest a possible biological mechanism for schizophrenia, whereby increased MMP-9 levels are associated with cognitive impairment.


Two children exhibiting social withdrawal, school refusal, and underlying generalized anxiety disorder successfully treated using a selective serotonin reuptake inhibitor.

Generalized anxiety disorder (GAD) sometimes exists in the background of social withdrawal and school refusal. Although clinical evidence suggests that selective serotonin reuptake inhibitors (SSRIs) are an effective treatment for GAD, they are not officially approved for GAD in Japan. In addition, it has been established that the use of SSRIs increases the risk for suicide and activation syndrome among young individuals. As such, there is currently little domestic clinical experience in prescribing SSRIs to young patients with GAD. The authors report two cases involving 10-year-old patients with GAD who were treated successfully with escitalopram and experienced subsequent improvement in social withdrawal and school refusal. One patient had autistic spectrum disorder and exhibited self-harm associated with anxiety symptoms, requiring careful use of SSRIs under hospitalization. The other patient was treated at an outpatient clinic without any side effects. In each case, improvement of anxiety symptoms with the use of SSRIs facilitated the introduction of psychoeducation and psychotherapy. It is important to accurately diagnose GAD, which may exist in the background of patients exhibiting social withdrawal and school refusal, and to treat the disorder appropriately. J. Med. Invest. 67 : 355-357, August, 2020.

The Journal of Medical Investigation : JMI


Behavioral and psychological symptoms of dementia (BPSD) and care burden : Examination in the facility staff for elderly residents.

Purpose : We investigated the cognitive function, behavioral and psychological symptoms of dementia (BPSD), and activities of daily living (ADLs) of elderly individuals admitted in care facilities. Moreover, the factors affecting the care burden experienced by facility staffs were examined. Method : 24 care facilities for elderly individuals participated in the study. The Revised Hasegawa Dementia Scale (HDS-R), Japanese version of the Neuropsychiatric Inventory (NPI), and Crichton Geriatric Behavioral Rating Scale (CGBRS) were used to evaluate cognitive function, BPSD, and ADL, respectively. The short Japanese version of the Zarit Burden Interview was used to assess the care burden. A multiple regression analysis was conducted with data obtained from 464 elderly individuals who fulfilled all the scales. Results : The care burden was correlated to the scores of HDS-R, but not with those of dysphoria/depression and disinhibition of NPI, restlessness of CGBRS, and subjective mood of CGBRS (R2 = 0.309, p < 0.005). Conclusion : Dysphoria/depression, disinhibition, restlessness, and subjective mood, but not cognitive decline, have an effect on the care burden experienced by facility staffs who manage elderly individuals. These results indicated that the appropriate diagnosis and treatment of BPSD are important in reducing the burden of facility staffs. J. Med. Invest. 67 : 236-239, August, 2020.


Epigenetic clock analysis of blood samples from Japanese schizophrenia patients.


Clinical factors influencing resilience in patients with anorexia nervosa

This study was to elucidate clinical factors influencing resilience in anorexia nervosa (AN) patients. Twenty female patients with AN (median age =30.0 years, quartile deviation =6.8) and 40 female healthy controls (HCs) (median age =30.0 years, quartile deviation =8.6) participated in the present study. Resilience was assessed with the Connor- Davidson resilience scale (CD-RISC). Clinical symptoms were evaluated with the structured interview guide for the Hamilton depression rating scale (SIGH-D) and the eating disorder inventory-2 (EDI-2). Scores of the CD-RISC in the AN group were lower than those in the HC group, and the SIGH-D score in the AN group was higher than that in the HC group. Scores of interoceptive confusion, interpersonal difficulty and negative self-image subscales of the EDI-2 negatively correlated with the CD-RISC score. Moreover, stepwise regression analysis showed that negative self-image score was an independent predictor of the CD-RISC score. These results suggest that among these clinical factors including psychopathologies, self-dissatisfaction and feeling of being rejected by others are the most important influencing factors on an AN patients' resilience.


Negative and positive self-thoughts predict subjective quality of life in people with schizophrenia.

Recently, cognitive variables such as negative and positive self-belief and thoughts have attracted much attention because they are associated with functional outcomes and quality of life (QOL). However, it is unclear how cognitive variables affect subjective and objective QOL. This study aimed to investigate the relationship of negative and positive self-belief and thoughts with subjective and objective QOL. Thirty-six people with schizophrenia participated in this study. Subjective and objective QOL were assessed with the Schizophrenia Quality of Life Scale (SQLS) and Quality of Life Scale (QLS), respectively. Neurocognitive function was assessed with the Brief Assessment of Cognition in Schizophrenia (BACS). Clinical symptoms were assessed with the Positive and Negative Syndrome Scale and Calgary Depression Scale for Schizophrenia. Side effects were assessed with the Drug-induced Extrapyramidal Symptoms Scale (DIEPSS). Negative and positive self-belief and thoughts were assessed with the Defeatist Performance Belief Scale and Automatic Thoughts Questionnaire-Revised. A generalized linear model was tested, with subjective and objective QOL as the response variable and symptoms, neurocognitive function, and cognitive variables that were significantly correlated with subjective and objective QOL as explanatory variables. In the schizophrenia group, the common objects score on the QLS was predicted by the composite BACS score, and the total QLS score was predicted by the DIEPSS score. Motivation and Energy, Psychosocial, and Symptoms and Side effects scores on the SQLS were predicted by depression and by negative automatic thought (NAT) and positive automatic thought (PAT). Our results indicated that key targets for improving objective and subjective QOL in people with schizophrenia are side effects, neurocognitive function, depression, and NAT and PAT.


Turning on the Left Side Electrode Changed Depressive State to Manic State in a Parkinson's Disease Patient Who Received Bilateral Subthalamic Nucleus Deep Brain Stimulation: A Case Report.

No previous reports have described a case in which deep brain stimulation elicited an acute mood swing from a depressive to manic state simply by switching one side of the bilateral deep brain stimulation electrode on and off. The patient was a 68-year-old woman with a 10-year history of Parkinson's disease. She underwent bilateral subthalamic deep brain stimulation surgery. After undergoing surgery, the patient exhibited hyperthymia. She was scheduled for admission. On the first day of admission, it was clear that resting tremors in the right limbs had relapsed and her hyperthymia had reverted to depression. It was discovered that the left-side electrode of the deep brain stimulation device was found to be accidentally turned off. As soon as the electrode was turned on, motor impairment improved and her mood switched from depression to mania. The authors speculate that the lateral balance of stimulation plays an important role in mood regulation. The current report provides an intriguing insight into possible mechanisms of mood swing in mood disorders.

Clinical Psychopharmacology and Neuroscience


Mitochondrial DNA copy number of peripheral blood in bipolar disorder: The present study and a meta-analysis.

Numerous evidence indicated mitochondrial abnormalities in the pathophysiology of bipolar disorder (BD); however, it remains unclear whether aberrant mitochondrial DNA (mtDNA) copy number (cn) occur in BD due to the conflicting results in previous studies. Here, peripheral blood mtDNAcn in 69 BD patients and 54 controls were analysed via qPCR. BD patients had significantly lower mtDNAcn compared to controls (regardless of their BD type [BD I or II]). Meta-analysis for all previous BD-mtDNAcn studies combining our results with previously published studies failed to identify any significant association. Meanwhile, Asian-specific meta-analysis remarkably revealed lower mtDNAcn in BD patients.


Clozapine Pharmacogenetic Studies in Schizophrenia: Efficacy and Agranulocytosis.

Clozapine is an efficacious atypical antipsychotic for treatment-refractory schizophrenia. Clinical response and appearance of adverse events vary among individual patients receiving clozapine, with genetic and non-genetic factors potentially contributing to individual variabilities. Pharmacogenetic studies investigate associations between genetic variants and drug efficacy and toxicity. To date, most pharmacogenetic studies of clozapine have been conducted through candidate gene approaches. A recent advance in technology made it possible to perform comprehensive genetic mapping underlying clinical phenotypes and outcomes, which allow novel findings beyond biological hypotheses based on current knowledge. In this paper, we will summarize the studies on clozapine pharmacogenetics that have extensively examined clinical response and agranulocytosis. While there is still limited evidence on clozapine efficacy, recent genome-wide studies provide further evidence of the involvement of the human leukocyte antigen (HLA) region in clozapine-induced agranulocytosis.


Comparative Analyses of Copy-Number Variation in Autism Spectrum Disorder and Schizophrenia Reveal Etiological Overlap and Biological Insights.

Compelling evidence in Caucasian populations suggests a role for copy-number variations (CNVs) in autism spectrum disorder (ASD) and schizophrenia (SCZ). We analyzed 1,108 ASD cases, 2,458 SCZ cases, and 2,095 controls in a Japanese population and confirmed an increased burden of rare exonic CNVs in both disorders. Clinically significant (or pathogenic) CNVs, including those at 29 loci common to both disorders, were found in about 8% of ASD and SCZ cases, which was significantly higher than in controls. Phenotypic analysis revealed an association between clinically significant CNVs and intellectual disability. Gene set analysis showed significant overlap of biological pathways in both disorders including oxidative stress response, lipid metabolism/modification, and genomic integrity. Finally, based on bioinformatics analysis, we identified multiple disease-relevant genes in eight well-known ASD/SCZ-associated CNV loci (e.g., 22q11.2, 3q29). Our findings suggest an etiological overlap of ASD and SCZ and provide biological insights into these disorders.


Relationship between social and cognitive functions in people with schizophrenia

The purpose of the present study was to examine clinical factors related to social function in people with schizophrenia. The participants were 55 stabilized outpatients with schizophrenia. Their mean age was 39.36 (SD =10.65) years. Social function was assessed using the Quality of Life Scale (QLS). Cognitive function was evaluated with the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB). Clinical symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale for Schizophrenia, and the Drug-Induced Extrapyramidal Symptoms Scale. Neither the MCCB cognitive domain score nor composite score was correlated with the QLS scores. However, of the 10 MCCB subtests, the Trail Making Test Part A and the Brief Assessment of Cognition in Schizophrenia-Symbol Coding (BACS-SC) scores were positively correlated with the QLS scores. Among clinical variables, especially the PANSS negative syndrome scale score had a strong negative correlation with the QLS scores. Stepwise regression analyses showed that the PANSS negative syndrome scale score was an independent predictor of the QLS scores, and although the BACS-SC score predicted the QLS common objects and activities subscale score, the association was not so strong compared to the PANSS negative syndrome scale score. These results indicate that speed of processing evaluated by BACS-SC could predict some aspect of social function but negative symptoms have a much stronger impact on global social function in people with schizophrenia.


Longer telomeres in elderly schizophrenia are associated with long-term hospitalization in the Japanese population.

Several previous studies have investigated an association between leukocyte telomere length (LTL) and schizophrenia (SCZ). However, results have been largely inconsistent, partially due to the relatively small sample sizes in each study and heterogeneity caused by various uncontrolled confounders (e.g., duration of illness or hospitalization, lifetime antipsychotic dose, and LTL assay methods). Here, we investigate the association of LTL with SCZ with the quantitative polymerase chain reaction method in independent cohorts consisting of 1241 patients with SCZ and 1042 controls (the largest independent sample in this field). Furthermore, we examined whether duration of hospitalization and lifetime antipsychotic dose had an effect on LTL in SCZ. In all samples, we observed significantly longer LTL in patients with SCZ relative to controls. In subgroup analyses, we observed that longer telomeres in SCZ were only visible in elderly patients and not in patients under 50 years old. Moreover, significantly longer LTL in elderly patients with SCZ was only specific to those with long-term hospitalization, but not outpatients or those with short-term hospitalization. This may be because the former received more appropriate lifestyle management. Meanwhile, lifetime antipsychotic dose had no effect on LTL. Our findings suggest that consideration of the effect of age and duration of hospitalization on LTL may improve our understanding of controversial results obtained in previous studies of telomeres in SCZ.


Plasma Levels of Soluble Tumor Necrosis Factor Receptor 2 (sTNFR2) are Associated with Hippocampal Volume and Cognitive Performance in Patients with Schizophrenia.

An imbalance in the inflammatory tumor necrosis factor system, including soluble tumor necrosis factor receptor 2 (sTNFR2), may contribute to the pathophysiology of schizophrenia. We measured the plasma levels of sTNFR2 in 256 healthy controls and 250 patients with schizophrenia including antipsychotic drug-free patients and treatment-resistant patients. We also explored the possible association between plasma sTNFR2 levels and cognitive performance in healthy controls and patients with schizophrenia using the Wechsler Adult Intelligence Scale, Third Edition, the Wechsler Memory Scale-Revised, and the Rey Auditory Verbal Learning Test. An association between plasma sTNFR2 levels and hippocampal volume in controls and patients with schizophrenia was also investigated via MRI. We found that the plasma levels of sTNFR2 were significantly higher in patients with schizophrenia, including both antipsychotic drug-free patients and treatment-resistant patients. We found a significant negative association between plasma sTNFR2 levels and cognitive performance in controls and patients with schizophrenia. Hippocampal volume was also negatively associated with plasma sTNFR2 levels in patients with schizophrenia. Together, these convergent data suggest a possible biological mechanism for schizophrenia, whereby increased sTNFR2 levels are associated with a smaller hippocampal volume and cognitive impairment.

The International Journal of Neuropsychopharmacology


Structural equation modeling approach between salience network dysfunction, depressed mood, and subjective quality of life in schizophrenia: an ICA resting-state fMRI study.

Quality of life (QOL) is an important clinical outcome for patients with schizophrenia, and recent studies have focused on subjective QOL. We evaluated the causal relationship between psychosocial aspect of subjective QOL, symptoms, cognitive functions, and salience network (SN) dysfunction in schizophrenia using structural equation modeling (SEM). We performed a cross-sectional study of 21 patients with symptomatically stabilized schizophrenia and 21 age-, sex-, and education level-matched healthy controls who underwent resting-state functional magnetic resonance imaging. We evaluated SN dysfunction in schizophrenia using independent component analysis (ICA). We rated participant psychopathology using the Positive and Negative Syndrome Scale (PANSS), the Brief Assessment of Cognition in Schizophrenia (BACS), and the Calgary Depression Scale for Schizophrenia (CDSS). We rated psychosocial aspect of subjective QOL using the Schizophrenia Quality of Life Scale (SQLS) psychosocial subscale. We applied SEM to examine the relationships between SN dysfunction, PANSS positive and negative scores, CDSS total scores, BACS composite scores, and SQLS psychosocial subscale scores. In second-level analysis after group ICA, patient group had significant lower right pallidum functional connectivity (FC) within the SN than the controls did (Montreal Neurological Institute [MNI] [] = [22 -2 -6]) ( = 0.027, family-wise error [FWE] corrected). In SEM, we obtained a good fit for an SEM model in which SN dysfunction causes depressed mood, which in turn determines psychosocial aspect of subjective QOL (chi-squared = 0.9, root mean square error of approximation (RMSEA) < 0.001, comparative fit index [CFI] = 1.00, and standardized root mean square residual [SRMR]= 0.020). We found a continuous process by which SN dysfunction causes depressed moods that determine psychosocial aspect of subjective QOL in schizophrenia. This is the first report that offers a unified explanation of functional neuroimaging, symptoms, and outcomes. Future studies combining neuroimaging techniques and clinical assessments would elucidate schizophrenia's pathogenesis.


Effect of cognitive function on jumping to conclusion in patients with schizophrenia.

The "jumping to conclusion" (JTC) bias is related to the formation and maintenance of delusions. Higher JTC bias can be based on both neurocognitive dysfunction and social cognitive dysfunction in patients with schizophrenia. The aim of this study was to assess the relationship between JTC bias, neurocognition, and social cognition in patients with schizophrenia. A total of 22 patients with schizophrenia and 21 controls participated in this study. Neurocognition and social cognition were assessed using the Brief Assessment of Cognition in Schizophrenia (BACS) and Social Cognition Screening Questionnaire (SCSQ), respectively. The JTC bias and the decision confidence were assessed using the beads task. The patients were classified into the JTC group (with higher JTC bias; n = 10) and JTC-non group (n = 12). The JTC group scored significantly lower on verbal memory, working memory, and motor speed sub-scores of BACS than the JTC-non group. No difference in social cognition was observed between the two groups. The decision confidence was predicted by metacognition, which is an SCSQ sub-score. Similarly to the patients, the controls were classified into the JTC group (higher JTC bias; n = 9) and the JTC-non group (n = 12). There were no significant differences in neurocognition and social cognition between the control JTC and JTC-non groups. The present results indicated that JTC bias is related to neurocognition and decision confidence is related to social cognition in patients with schizophrenia. These findings may bridge the gaps between psychotic symptom and cognitive dysfunction in schizophrenia.


Decreased serum pyridoxal levels in schizophrenia: meta-analysis and Mendelian randomization analysis.

Alterations in one-carbon metabolism have been associated with schizophrenia, and vitamin B6 is one of the key components in this pathway. We first conducted a case-control study of serum pyridoxal levels and schizophrenia in a large Japanese cohort ( = 1276). Subsequently, we conducted a meta-analysis of association studies ( = 2125). Second, we investigated whether rs4654748, which was identified in a genome-wide association study as a vitamin B6-related single nucleotide polymorphism, was genetically implicated in patients with schizophrenia in the Japanese population ( = 10 689). Finally, we assessed the effect of serum pyridoxal levels on schizophrenia risk using a Mendelian randomization (MR) approach. Serum pyridoxal levels were significantly lower in patients with schizophrenia than in controls, not only in our cohort, but also in the pooled data set of the meta-analysis of association studies (standardized mean difference -0.48, 95% confidence interval [CI] -0.57 to -0.39, = 9.8 × 10-24). We failed to find a significant association between rs4654748 and schizophrenia. Furthermore, an MR analysis failed to find a causal relationship between pyridoxal levels and schizophrenia risk (odds ratio 0.99, 95% CI 0.65-1.51, = 0.96). Food consumption and medications may have affected serum pyridoxal levels in our cross-sectional study. Sample size, number of instrumental variables and substantial heterogeneity among patients with schizophrenia are limitations of an MR analysis. We found decreased serum pyridoxal levels in patients with schizophrenia in this observational study. However, we failed to obtain data supporting a causal relationship between pyridoxal levels and schizophrenia risk using the MR approach.


Increased serum levels and promoter polymorphisms of macrophage migration inhibitory factor in schizophrenia.

Numerous studies have suggested that an immune system imbalance plays an important role in schizophrenia. Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine. It plays multiple roles in various biological processes, including inflammation and neurogenesis. Furthermore, several exhaustive serum proteomic profiling studies have identified MIF as a potential biomarker of schizophrenia. Here, we investigate MIF protein levels in serum and postmortem prefrontal cortex in patients with schizophrenia and controls. Moreover, we investigate the association of two functional polymorphisms in the MIF gene promoter region (MIF-794CATT microsatellite and MIF-173G/C single-nucleotide polymorphism [SNP]) with schizophrenia. We measured serum MIF levels with an enzyme-linked immunosorbent assay (ELISA) (51 patients vs. 86 controls) and postmortem brain MIF levels with a western blotting assay (18 patients vs. 22 controls). Subsequently, we genotyped the MIF-794CATT microsatellite with a fluorescence-based fragment assay and the MIF-173G/C SNP with a TaqMan SNP genotyping assay (1483 patients vs. 1454 controls). Serum MIF levels were significantly higher in patients with schizophrenia than in controls (p=0.00118), and were positively correlated with antipsychotic dose (Spearman's r=0.222, p=0.0402). In addition, an earlier age of onset was observed in patients with a high serum MIF level (≥40ng/mL) than those with a low serum MIF level (<40ng/mL) (p=0.0392). However, postmortem brain MIF levels did not differ between patients with schizophrenia and controls. The association study revealed that the CATT-G haplotype was nominally significantly associated with schizophrenia (p=0.0338), and that the CATT allele and CATT-G haplotype were significantly associated with female adolescent-onset schizophrenia (AsOS) (corrected p=0.0222 and p=0.0147, respectively). These results suggest that serum MIF level is a potential pharmacodynamic and/or monitoring marker of schizophrenia, and is related to a novel antipsychotic effect beyond dopamine antagonism. Furthermore, the MIF gene polymorphisms are associated with the risk for schizophrenia especially in adolescent females, and are potential stratification markers of schizophrenia. Further studies of MIF are warranted to elucidate the pathophysiology of schizophrenia and the effects of antipsychotics.

Progress in Neuro-Psychopharmacology & Biological Psychiatry


Elevated peripheral blood glutamate levels in major depressive disorder.

There is growing evidence that glutamatergic signaling may be involved in major depressive disorder (MDD). In regard to peripheral blood glutamate changes in MDD, inconsistent findings have been reported. The purpose of the present study was to evaluate whether blood glutamate levels differed between MDD patients and control participants. We conducted a systematic review and meta-analysis of 12 association studies between blood glutamate levels and MDD in a total of 529 MDD patients and 590 controls. Subsequently, we conducted subgroup analyses and a meta-regression analysis to examine the sources of potential heterogeneity. A random effects model showed that blood glutamate levels were significantly higher in MDD patients than in controls (standardized mean difference=0.54, 95% CI=0.27-0.82, =8.5×10) with high heterogeneity (=75.0%, <0.05). Subgroup analyses showed elevated glutamate levels in MDD patients compared with controls in plasma, but not serum studies, and in studies using high-performance liquid chromatography but not with mass spectrometry for glutamate assay. A meta-regression analysis showed no effects of age, gender, medication use, sample size, and published year on blood glutamate levels. Our findings suggest that altered glutamate levels may be implicated in MDD, which provides further evidence of glutamatergic dysfunction in MDD.


A Genome-Wide Association Study Identifies Two Novel Susceptibility Loci and Trans Population Polygenicity Associated With Bipolar Disorder.

Genome-wide association studies (GWASs) have identified several susceptibility loci for bipolar disorder (BD) and shown that the genetic architecture of BD can be explained by polygenicity, with numerous variants contributing to BD. In the present GWAS (Phase I/II), which included 2964 BD and 61 887 control subjects from the Japanese population, we detected a novel susceptibility locus at 11q12.2 (rs28456, P=6.4 × 10), a region known to contain regulatory genes for plasma lipid levels (FADS1/2/3). A subsequent meta-analysis of Phase I/II and the Psychiatric GWAS Consortium for BD (PGC-BD) identified another novel BD gene, NFIX (P=5.8 × 10), and supported three regions previously implicated in BD susceptibility: MAD1L1 (P=1.9 × 10), TRANK1 (P=2.1 × 10) and ODZ4 (P=3.3 × 10). Polygenicity of BD within Japanese and trans-European-Japanese populations was assessed with risk profile score analysis. We detected higher scores in BD cases both within (Phase I/II) and across populations (Phase I/II and PGC-BD). These were defined by (1) Phase II as discovery and Phase I as target, or vice versa (for 'within Japanese comparisons', P~10, R~2%), and (2) European PGC-BD as discovery and Japanese BD (Phase I/II) as target (for 'trans-European-Japanese comparison,' P~10, R~0.27%). This 'trans population' effect was supported by estimation of the genetic correlation using the effect size based on each population (liability estimates~0.7). These results indicate that (1) two novel and three previously implicated loci are significantly associated with BD and that (2) BD 'risk' effect are shared between Japanese and European populations.


Clinical factors influencing quality of life in anorexia nervosa patients


Functional Independence Measure を用いて評価した統合失調症患者の基本的な社会生活機能と臨床諸要因との関連


Impaired central coherence in patients with anorexia nervosa

The purpose of this study was to investigate the characteristics of central coherence in patients with anorexia nervosa (AN). 22 female patients with AN (median age = 31.50 (QD = 8.13) years) and 33 female healthy controls (HC) (median age = 28.00 (QD = 8.50) years) participated in the study. Their central coherence was assessed with the Rey Complex Figure Task (RCFT). Clinical symptoms were evaluated with the Beck Depression Inventory-II and the State-Trait Anxiety Inventory-Form JYZ. The results showed that AN patients' Central Coherence Index and accuracy scores in copy, 3-min delayed recall and 30-min delayed recall tasks of the RCFT were significantly lower than those of HC. Moreover, the significant differences in Central Coherence Index score in copy task and accuracy scores in 3-min delayed recall and 30-min delayed recall tasks remained when the effects of depression, anxiety and starvation were eliminated statistically. These findings may explain some characteristics of AN patients such as focusing on local rather than global picture in their perception of body or life.


Association of schizophrenia onset age and white matter integrity with treatment effect of D-cycloserine: a randomized placebo-controlled double-blind crossover study.

It has been reported that drugs which promote the N-Methyl-D-aspartate-type glutamate receptor function by stimulating the glycine modulatory site in the receptor improve negative symptoms and cognitive dysfunction in schizophrenia patients being treated with antipsychotic drugs. We performed a placebo-controlled double-blind crossover study involving 41 schizophrenia patients in which D-cycloserine 50 mg/day was added-on, and the influence of the onset age and association with white matter integrity on MR diffusion tensor imaging were investigated for the first time. The patients were evaluated using the Positive and Negative Syndrome Scale (PANSS), Scale for the Assessment of Negative Symptoms (SANS), Brief Assessment of Cognition in Schizophrenia (BACS), and other scales. D-cycloserine did not improve positive or negative symptoms or cognitive dysfunction in schizophrenia. The investigation in consideration of the onset age suggests that D-cycloserine may aggravate negative symptoms of early-onset schizophrenia. The better treatment effect of D-cycloserine on BACS was observed when the white matter integrity of the sagittal stratum/ cingulum/fornix stria terminalis/genu of corpus callosum/external capsule was higher, and the better treatment effect on PANSS general psychopathology (PANSS-G) was observed when the white matter integrity of the splenium of corpus callosum was higher. In contrast, the better treatment effect of D-cycloserine on PANSS-G and SANS-IV were observed when the white matter integrity of the posterior thalamic radiation (left) was lower. It was suggested that response to D-cycloserine is influenced by the onset age and white matter integrity. UMIN Clinical Trials Registry (number UMIN000000468 ). Registered 18 August 2006.


Altered KYN/TRP, Gln/Glu, and Met/methionine sulfoxide ratios in the blood plasma of medication-free patients with major depressive disorder.

Capillary electrophoresis-time-of-flight mass spectrometry (CE-TOFMS) is a comprehensive, quantitative, and high throughput tool used to analyze metabolite profiles. In the present study, we used CE-TOFMS to profile metabolites found in the blood plasma of 33 medication-free patients with major depressive disorder (MDD) and 33 non-psychiatric control subjects. We then investigated changes which occurred in the metabolite levels during an 8-week treatment period. The medication-free MDD patients and control subjects showed significant differences in their mean levels of 33 metabolites, including kynurenine (KYN), glutamate (Glu), glutamine (Gln), methionine sulfoxide, and methionine (Met). In particular, the ratios of KYN to tryptophan (TRP), Gln to Glu, and Met to methionine sulfoxide were all significantly different between the two groups. Among the 33 metabolites with altered levels in MDD patients, the levels of KYN and Gln, as well as the ratio of Gln to Glu, were significantly normalized after treatment. Our findings suggest that imbalances in specific metabolite levels may be involved in the pathogenesis of MDD, and provide insight into the mechanisms by which antidepressant agents work in MDD patients.


Transethnic Replication Study to Assess the Association Between Clozapine-Induced Agranulocytosis/Granulocytopenia and Genes at 12p12.2 in a Japanese Population.


大学におけるメンタルヘルス対策の検討 入学時のメンタルヘルス健診と在学中の精神科受療行動との関連から

Japanese Journal of Psychiatric Treatment


Effect of Clozapine on DNA Methylation in Peripheral Leukocytes from Patients with Treatment-Resistant Schizophrenia.

Clozapine is an atypical antipsychotic, that is established as the treatment of choice for treatment-resistant schizophrenia (SCZ). To date, no study investigating comprehensive DNA methylation changes in SCZ patients treated with chronic clozapine has been reported. The purpose of the present study is to reveal the effects of clozapine on DNA methylation in treatment-resistant SCZ. We conducted a genome-wide DNA methylation profiling in peripheral leukocytes (485,764 CpG dinucleotides) from treatment-resistant SCZ patients treated with clozapine (n = 21) in a longitudinal study. Significant changes in DNA methylation were observed at 29,134 sites after one year of treatment with clozapine, and these genes were enriched for "cell substrate adhesion" and "cell matrix adhesion" gene ontology (GO) terms. Furthermore, DNA methylation changes in the CREBBP (CREB binding protein) gene were significantly correlated with the clinical improvements. Our findings provide insights into the action of clozapine in treatment-resistant SCZ.

International Journal of Molecular Sciences


Prefrontal cortex activation during neuropsychological tasks might predict response to pharmacotherapy in patients with obsessive-compulsive disorder.

We investigated oxyhemoglobin change in the prefrontal cortex (PFC) of patients with obsessive-compulsive disorder (OCD) who showed different responses to pharmacotherapy during neuropsychological tasks with near-infrared spectroscopy. A total of 42 patients with OCD (mean age: 35.6±9.6 years, 14 men, 28 women) and healthy control subjects (mean age: 35.4±9.7 years, 13 men, 29 women) were selected. Patients with OCD were divided into three groups (responders to selective serotonin-reuptake inhibitors (SSRIs), responders to SSRIs with antipsychotics, and nonresponders to SSRIs and SSRIs with antipsychotics) based on pharmacological response. We investigated oxyhemoglobin change in the PFC of subjects during Stroop tasks and a verbal fluency test with near-infrared spectroscopy. Responders to SSRIs showed smaller activation compared to control subjects during the Stroop incongruent task and verbal fluency test, but not during the Stroop congruent task. In contrast, responders to SSRIs with antipsychotics showed smaller activation compared to control subjects during all three tasks. Our results suggest that activation of the PFC during Stroop tasks might predict responses to pharmacotherapy of patients with OCD.


Gene expression-based biological test for major depressive disorder: an advanced study.

Recently, we could distinguished patients with major depressive disorder (MDD) from nonpsychiatric controls with high accuracy using a panel of five gene expression markers (ARHGAP24, HDAC5, PDGFC, PRNP, and SLC6A4) in leukocyte. In the present study, we examined whether this biological test is able to discriminate patients with MDD from those without MDD, including those with schizophrenia and bipolar disorder. We measured messenger ribonucleic acid expression levels of the aforementioned five genes in peripheral leukocytes in 17 patients with schizophrenia and 36 patients with bipolar disorder using quantitative real-time polymerase chain reaction (PCR), and we combined these expression data with our previous expression data of 25 patients with MDD and 25 controls. Subsequently, a linear discriminant function was developed for use in discriminating between patients with MDD and without MDD. This expression panel was able to segregate patients with MDD from those without MDD with a sensitivity and specificity of 64% and 67.9%, respectively. Further research to identify MDD-specific markers is needed to improve the performance of this biological test.


Influence of cognitive function on quality of life in anorexia nervosa patients

The purpose of this study was to elucidate determinants of quality of life (QOL) in anorexia nervosa (AN) patients. Twenty-one female patients with AN participated in the study. QOL was assessed with the 36-Item Short Form Health Survey (SF-36), and cognitive function was evaluated using the Wisconsin Card Sorting Test Keio version, the Rey Complex Figure Test, and the Social Cognition Screening Questionnaire. Clinical symptoms were evaluated with the Beck Depression Inventory-II, the State-Trait Anxiety Inventory-Form JYZ (STAI-JYZ), and the Maudsley Obsessive Compulsive Inventory. The Difficulty Maintaining Set score of the Wisconsin Card Sorting Test Keio version was negatively correlated to the SF-36 Physical Component Summary. Scores of the Beck Depression Inventory-II and the STAI-JYZ State and Trait were negatively correlated to the SF-36 Mental Component Summary (MCS), and the Central Coherence Index 30-min Delayed Recall score of the Rey Complex Figure Test was positively correlated with the MCS. Stepwise regression analysis showed that the Difficulty Maintaining Set score was an independent predictor of the Physical Component Summary and scores for Central Coherence Index 30-min Delayed Recall and the STAI-JYZ Trait-predicted MCS. These results suggest that not only trait anxiety but also poor central coherence and impaired ability to maintain new rule worsen AN patients' QOL.


1H-magnetic resonance spectroscopy study of glutamate-related abnormality in bipolar disorder.

Previous studies of patients with bipolar disorder (BD) using magnetic resonance spectroscopy (MRS) have shown neurophysiological abnormalities related to the glutamate (Glu)-glutamine (Gln) cycle, membrane turnover, and neuronal integrity, although the results were neither consistent nor conclusive. Recently it has been reported the Gln/Glu ratio is the most useful index, quantifying neuronal-glial interactions and the balance of glutamatergic metabolites In this MRS study, we elucidated the abnormalities of metabolites in a larger sample of patients with BD with a high-field MRI system. Sixty-two subjects (31 patients with BD and 31 healthy controls [HC]) underwent 3T proton MRS (1H-MRS) of the anterior cingulate cortex (ACC) and left basal ganglia (ltBG) using a stimulated echo acquisition mode (STEAM) sequence. After verifying the data quality, 20 patients with BD and 23 age- and gender-matched HCs were compared using repeated-measures analysis of covariance (ANCOVA). Compared to the HC group, the BD group showed increased levels of Gln, creatine (Cr), N-acetyl aspartate (NAA), choline (Cho), and an increased ratio of Gln to Glu in the ACC, and increased Gln and Cho in the ltBG. These findings remained after the participants with BD were limited to only euthymic patients. After removing the influence of lithium (Li) and sodium valproate (VPA), we observed activated glutamatergic neurotransmission in the ACC but not in the ltBG. The present findings are cross-sectional and metabolites were measured in only two regions. Our results support a wide range of metabolite changes in patients with BD involved in glutamatergic neurotransmission, membrane turnover, and neuronal integrity. Moreover, the elevation of Gln/Glu ratio suggested that hyperactivity of glutamatergic neurotransmission in the ACC is a disease marker for BD.


留学生のキャンパス内の精神科受診傾向の検討

留学生のキャンパス内の精神科受診傾向の検討


認知行動療法的介入が有効であった心因性難聴の事例

認知行動療法的介入が有効であった心因性難聴の事例

Japanese Journal of Child and Adolescent Psychiatry

児童青年精神医学とその近接領域


Cumulative effect of the plasma total homocysteine-related genetic variants on schizophrenia risk.

Previous studies suggest that elevated total homocysteine levels and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, which correlates with plasma total homocysteine levels, are risk factors for schizophrenia (SCZ). Recently, a large genome-wide association study (GWAS) of plasma total homocysteine levels in individuals of European ancestry identified many single-nucleotide polymorphisms (SNPs) (n=13,974). The primary purpose of this study was to examine the association between these plasma total homocysteine-related SNPs and SCZ in the Japanese population. First, we investigated associations between six SNPs and plasma total homocysteine levels in non-psychiatric subjects in the Japanese population (n=1030). Then, we evaluated the cumulative effects of three SNPs on SCZ risk by calculating the Genotype Risk Score (GRS) (1120 cases, 2643 controls). Of the six SNPs examined, we replicated similar associations with the European GWAS at four loci (CENPQ, CPS1, MTHFR, and MUT). GRS based on three SNPs (CENPQ, CPS1, and MTHFR) was significantly associated with SCZ. Our findings suggest that common polygenic variations, which are associated with the plasma total homocysteine levels, may contribute to the risk of SCZ.


Impaired social cognition in anorexia nervosa patients

The purpose of this study was to investigate the characteristics of social cognition in patients with anorexia nervosa (AN). Eighteen female patients with AN (mean age =35.4±8.6 years) and 18 female healthy controls (HC) (mean age =32.8±9.4 years) participated in the study. Their social cognition was assessed with the Social Cognition Screening Questionnaire (SCSQ). The results showed that total score of the SCSQ and scores of theory of mind and metacognition were significantly lower in AN group than those in HC group. Moreover, significant differences in theory of mind, metacognition, and total score of the SCSQ remained when the effects of depression, anxiety, and starvation were eliminated statistically. These results suggest that patients with AN may have difficulty inferring other people's intention and also monitoring and evaluating their own cognitive activities. Therefore, these features may explain some aspects of the pathology of AN.


Low methylation rates of dopamine receptor D2 gene promoter sites in Japanese schizophrenia subjects.

According to the dopamine hypothesis, several studies on the gene for the dopamine receptor D2 (DRD2) have been conducted. However, no trait biomarkers on DRD2 are available. We examined whether the methylation rates in the upstream region of DRD2 in leukocytes are different in schizophrenia (SCZ) subjects compared to control subjects. We selected seven CpG sites in the upstream region of DRD2 that may theoretically bind major transcription factors. The methylation rates in these regions of 50 medicated and 18 drug-naïve SCZ subjects were compared with those of age-matched control subjects. The methylation rates were significantly lower in medicated (CpG2, P < 0.0001; CpG4, P = 0.013; CpG7, P < 0.0001; and average: 12.9 ± 1.8 vs. 14.1 ± 2.2, P = 0.005) and drug-naïve SCZ subjects (CpG1, P = 0.006; CpG2, P = 0.001; CpG3, P = 0.001; CpG5, P = 0.02; CpG6, P = 0.015; CpG7, P = 0.027; and average: 9.86 ± 0.9 vs. 11.2 ± 1.3, P = 0.002). We confirmed low methylation rates in the upstream region of DRD2 in both medicated and drug-naïve SCZ subjects. Low methylation rates of DRD2 in leukocytes may be a trait biomarker for SCZ.

The World Journal of Biological Psychiatry


Calcium Signaling Pathway Is Associated with the Long-Term Clinical Response to Selective Serotonin Reuptake Inhibitors (SSRI) and SSRI with Antipsychotics in Patients with Obsessive-Compulsive Disorder.

Selective serotonin reuptake inhibitors (SSRI) are established first-line pharmacological treatments for obsessive-compulsive disorder (OCD), while antipsychotics are used as an augmentation strategy for SSRI in OCD patients who have either no response or a partial response to SSRI treatment. The goal of the present study was to identify genetic variants and pathways that are associated with the long-term clinical response of OCD patients to SSRI or SSRI with antipsychotics. We first performed a genome-wide association study of 96 OCD patients to examine genetic variants contributing to the response to SSRI or SSRI with antipsychotics. Subsequently, we conducted pathway-based analyses by using Improved Gene Set Enrichment Analysis for Genome-wide Association Study (i-GSEA4GWAS) to examine the combined effects of genetic variants on the clinical response in OCD. While we failed to detect specific genetic variants associated with clinical responses to SSRI or to SSRI with an atypical antipsychotic at genome-wide levels of significance, we identified 8 enriched pathways for the SSRI treatment response and 5 enriched pathways for the treatment response to SSRI with an antipsychotic medication. Notably, the calcium signaling pathway was identified in both treatment responses. Our results provide novel insight into the molecular mechanisms underlying the variability in clinical response to SSRI and SSRI with antipsychotics in OCD patients.


High-resolution copy number variation analysis of schizophrenia in Japan

Recent schizophrenia (SCZ) studies have reported an increased burden of de novo copy number variants (CNVs) and identified specific high-risk CNVs, although with variable phenotype expressivity. However, the pathogenesis of SCZ has not been fully elucidated. Using array comparative genomic hybridization, we performed a high-resolution genome-wide CNV analysis on a mainly (92%) Japanese population (1699 SCZ cases and 824 controls) and identified 7066 rare CNVs, 70.0% of which were small (<100 kb). Clinically significant CNVs were significantly more frequent in cases than in controls (odds ratio=3.04, P=9.3 × 10(-9), 9.0% of cases). We confirmed a significant association of X-chromosome aneuploidies with SCZ and identified 11 de novo CNVs (e.g., MBD5 deletion) in cases. In patients with clinically significant CNVs, 41.7% had a history of congenital/developmental phenotypes, and the rate of treatment resistance was significantly higher (odds ratio=2.79, P=0.0036). We found more severe clinical manifestations in patients with two clinically significant CNVs. Gene set analysis replicated previous findings (e.g., synapse, calcium signaling) and identified novel biological pathways including oxidative stress response, genomic integrity, kinase and small GTPase signaling. Furthermore, involvement of multiple SCZ candidate genes and biological pathways in the pathogenesis of SCZ was suggested in established SCZ-associated CNV loci. Our study shows the high genetic heterogeneity of SCZ and its clinical features and raises the possibility that genomic instability is involved in its pathogenesis, which may be related to the increased burden of de novo CNVs and variable expressivity of CNVs.Molecular Psychiatry advance online publication, 31 May 2016; doi:10.1038/mp.2016.88.


Elevated TREM2 mRNA Expression in Leukocytes in Schizophrenia but not Major Depressive Disorder

The pathological mechanisms of schizophrenia (SCZ) have not been clarified, but the microglia hypothesis has recently been discussed. We previously reported that the mRNA for a protein related to activation of microglia, triggering receptor expressed on myeloid cell 2 (TREM2), is expressed higher in peripheral leukocytes in SCZ than controls. In this study, we analyzed TREM2 mRNA expression in leukocytes from both SCZ and major depressive disorder (MDD) patients. We compared 50 SCZ patients and 42 MDD patients with age-matched controls. Levels of TREM2 mRNA in leukocytes were analyzed with quantitative real-time PCR method using TaqMan probe. TREM2 mRNA expression was significantly higher in leukocytes of SCZ subjects than controls, but the expression level was non-significantly different in MDD subjects. We observed a decrease in TREM2 mRNA expression in leukocytes from one SCZ patient after clozapine treatment. The expression did not change following ECT, but the expression level in this patient was still significantly higher than that in controls. We conclude that the high amount of TREM2 mRNA expression in leukocytes is specific to SCZ but not MDD and that changes in TREM2 mRNA expression may be a trait biomarker for SCZ.


Association study of polymorphism in the serotonin transporter gene promoter, methylation profiles, and expression in patients with major depressive disorder.

The serotonin transporter (5HTT) may be associated with the pathogenesis of major depressive disorder (MDD). The 5HTT-linked polymorphic region (5HTTLPR) genotype may determine how levels of 5HTT mRNA are influenced by promoter methylation. We examined the association of 5HTT gene methylation, which influences gene expression, and the 5HTTLPR genotype before antidepressant treatment and expression before and after treatment. The aims of this study were (1) to investigate the association between 5HTT methylation or expression in leukocytes and depression and (2) to investigate a possible effect of 5HTT methylation, expression, and genotype on clinical symptoms in MDD. The 5HTTLPR genotype was significantly associated with mean methylation levels in patients only (patients: r = 0.40, p = 0.035, controls: p = 0.96). The mean methylation level was significantly increased in patients compared with controls (patients: 5.30 ± 0.24, controls: 4.70 ± 0.19, unpaired t-test, p = 0.04). 5HTT expression using real-time PCR and Taqman probes was increased in unmedicated patients compared with controls and then decreased 8 weeks after antidepressant treatment. The mean 5HTT expression level was not associated with the 5HTTLPR genotype in patients or controls. Increased depressive symptoms were related to decreased levels of methylation. Copyright © 2016 John Wiley & Sons, Ltd.


No association between BDNF Val66Met polymorphism and treatment response in obsessive-compulsive disorder in the Japanese population.

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family, and it promotes the development and function of dopaminergic and serotonergic neurons. The Met allele of the BDNF Val66Met polymorphism is associated with a decrease in activity-dependent secretion of BDNF compared with the Val allele, and a number of studies have provided evidence for the association between this polymorphism and obsessive-compulsive disorder (OCD). The purpose of this study was to investigate whether this functional variant of the BDNF gene is associated with OCD and treatment response in patients with OCD in the Japanese population. We first performed a case-control association study between the BDNF Val66Met polymorphism and OCD (175 cases and 2,027 controls). Then, we examined an association between this polymorphism and treatment response in 96 patients with OCD. We found no significant association between the Met allele and OCD risk or between the Met allele and treatment responses to selective serotonin reuptake inhibitors or serotonin reuptake inhibitor with an atypical antipsychotic (P>0.05). Our results suggest that the BDNF Val66Met polymorphism may not be associated as a risk factor for developing OCD or with therapeutic response in patients with OCD in the Japanese population.


Pharmacogenomic Study of Clozapine-Induced Agranulocytosis/Granulocytopenia in a Japanese Population.

Clozapine-induced agranulocytosis (CIA)/clozapine-induced granulocytopenia (CIG) (CIAG) is a life-threatening event for schizophrenic subjects treated with clozapine. To examine the genetic factor for CIAG, a genome-wide pharmacogenomic analysis was conducted using 50 subjects with CIAG and 2905 control subjects. We identified a significant association in the human leukocyte antigen (HLA) region (rs1800625, p = 3.46 × 10(-9), odds ratio [OR] = 3.8); therefore, subsequent HLA typing was performed. We detected a significant association of HLA-B*59:01 with CIAG (p = 3.81 × 10(-8), OR = 10.7) and confirmed this association by comparing with an independent clozapine-tolerant control group (n = 380, p = 2.97 × 10(-5), OR = 6.3). As we observed that the OR of CIA (OR: 9.3~15.8) was approximately double that in CIG (OR: 4.4~7.4), we hypothesized that the CIG subjects were a mixed population of those who potentially would develop CIA and those who would not develop CIA (non-CIA). This hypothesis allowed the proportion of the CIG who were non-CIA to be calculated, enabling us to estimate the positive predictive value of the nonrisk allele on non-CIA in CIG subjects. Assuming this model, we estimated that 1) ~50% of CIG subjects would be non-CIA; and 2) ~60% of the CIG subjects without the risk allele would be non-CIA and therefore not expected to develop CIA. Our results suggest that HLA-B*59:01 is a risk factor for CIAG in the Japanese population. Furthermore, if our model is true, the results suggest that rechallenging certain CIG subjects with clozapine may not be always contraindicated.


Clinical correlates associated with basic ability of social life in schizophrenia inpa-tients


Relationship between cognitive function and employment in Japanese schizophrenia patients


The Report of the Survey to the Members of the Society about the Functional Dissociation of the Psychiatric Hospital beds

「病床機能分化と地域移行」に関する学会員へのアンケート調査結果報告

精神保健福祉法第41条の「指針」の中の「病床機能分化」に関して，日本精神神経学会会員の意見を把握することを目的にアンケート調査を実施した．平成27年5月1∼30日の間に学会ホームページに質問事項(9項目)を掲載し，回答者が特定されないよう，web上で回答を求める手法で調査を行った．862名(会員全体の5.3%)の回答が得られた．回答の動向をみると，賛成群が圧倒的に多かった(80%以上)質問項目は，「回復期入院治療を多職種で充実する」「重度かつ慢性患者については病状の程度に応じて処遇する」「地域移行は受け皿の整備状況を見ながら進める」の3項目であった．賛成群がやや多かった(55∼62%)質問項目は，「急性期充実のために慢性期病床を削減する」「身体合併症・高齢者については病床転換型老健類似施設で処遇する」「病院内の人材を地域に移動させる必要がある」の3項目であった．反対群が賛成群よりもやや多かった(反対が47%程度)質問項目は，「慢性患者の症状評価は第三者機関で」「生活訓練施設は地域内に置くべきである」の2項目であった．アンケート調査によって各種問題に対する会員の意向を知ることができ，極めて有意義な調査であった．


Risk factors for refeeding hypophosphatemia in Japanese inpatients with anorexia nervosa.

Refeeding in patients with anorexia nervosa (AN) is associated with a risk of refeeding syndrome, which is a disruption in metabolism with a variety of features including hypophosphatemia. We evaluated the risk factors for refeeding hypophosphatemia (RH) during nutritional replenishment in Japanese patients with AN. We retrospectively examined clinical data for 99 female inpatients (mean age 30.9 ± 10.7 years; range, 9 - 56 years). RH (phosphate < 2.3 mg/dL) occurred within 4.8 ± 3.7 days of hospital admission and was still observed at 28 days after admission in 21 of the 99 cases (21.2%). Oral or intravenous phosphate was given to some patients to treat or prevent RH. Patients with RH had a significantly lower body mass index, were older, and had higher blood urea nitrogen than those without RH. Severe complications associated with RH were recorded in only one patient who showed convulsions and disturbed consciousness at Day 3 when her serum phosphate level was 1.6 mg/dL. The significant risk factors for RH that we identified were lower body mass index, older age, and higher blood urea nitrogen at admission. No significant difference in total energy intake was seen between the RH and no RH groups, suggesting that RH may not be entirely correlated with energy intake. Precisely predicting and preventing RH is difficult, even in patients with AN who are given phosphate for prophylaxis. Thus, serum phosphate levels should be monitored for more than 5 days after admission.

The International Journal of Eating Disorders


成人高機能自閉症スペクトラム障害におけるWechsler式知能検査と自閉症スペクトラム指数との関連


TREM2 mRNA Expression in Leukocytes Is Increased in Alzheimer's Disease and Schizophrenia.

TREM2 and TYROBP are causal genes for Nasu-Hakola disease (NHD), a rare autosomal recessive disease characterized by bone lesions and early-onset progressive dementia. TREM2 forms a receptor signaling complex with TYROBP, which triggers the activation of immune responses in macrophages and dendritic cells, and the functional polymorphism of TREM2 is reported to be associated with neurodegenerative disorders such as Alzheimer's disease (AD). The objective of this study was to reveal the involvement of TYROBP and TREM2 in the pathophysiology of AD and schizophrenia. We investigated the mRNA expression level of the 2 genes in leukocytes of 26 patients with AD and 24 with schizophrenia in comparison with age-matched controls. Moreover, we performed gene association analysis between these 2 genes and schizophrenia. No differences were found in TYROBP mRNA expression in patients with AD and schizophrenia; however, TREM2 mRNA expression was increased in patients with AD and schizophrenia compared with controls (P < 0.001). There were no genetic associations of either gene with schizophrenia in Japanese patients. TREM2 expression in leukocytes is elevated not only in AD but also in schizophrenia. Inflammatory processes involving TREM2 may occur in schizophrenia, as observed in neurocognitive disorders such as AD. TREM2 expression in leukocytes may be a novel biomarker for neurological and psychiatric disorders.


Evaluation of an association between plasma total homocysteine and schizophrenia by a Mendelian randomization analysis.

The results of meta-analyses conducted by previous association studies between total homocysteine and schizophrenia suggest that an elevated total homocysteine level is a risk factor for schizophrenia. However, observational studies have potential limitations, such as confounding and reverse causation. In the present study, we evaluated a causal relationship between plasma total homocysteine and schizophrenia by conducting a Mendelian randomization analysis. We used the MTHFR C677T polymorphism as an instrumental variable, which affects the plasma total homocysteine levels. To calculate the risk estimate for the association of this single nucleotide polymorphism (SNP) with schizophrenia, we conducted a meta-analysis of case-control studies that comprise a total of 11,042 patients with schizophrenia and 14,557 control subjects. We obtained an estimate for the association of this SNP with the plasma total homocysteine levels from a meta-analysis of genome-wide association studies comprising 44,147 individuals. By combining these two estimates, we demonstrated a significant effect of the plasma total homocysteine on schizophrenia risk, representing an OR of 2.15 (95 % CI = 1.39-3.32; p = 5.3 x 10(-4)) for schizophrenia per 1-SD increase in the natural log-transformed plasma total homocysteine levels. We provided evidence of a causal relationship between the plasma total homocysteine and schizophrenia, and this result will add insight into the pathology and treatment of schizophrenia.


Sex differences of leukocytes DNA methylation adjusted for estimated cellular proportions.

DNA methylation, which is most frequently the transference of a methyl group to the 5-carbon position of the cytosine in a CpG dinucleotide, plays an important role in both normal development and diseases. To date, several genome-wide methylome studies have revealed sex-biased DNA methylation, yet no studies have investigated sex differences in DNA methylation by taking into account cellular heterogeneity. The aim of the present study was to investigate sex-biased DNA methylation on the autosomes in human blood by adjusting for estimated cellular proportions because cell-type proportions may vary by sex. We performed a genome-wide DNA methylation profiling of the peripheral leukocytes in two sets of samples, a discovery set (49 males and 44 females) and a replication set (14 males and 10 females) using Infinium HumanMethylation450 BeadChips for 485,764 CpG dinucleotides and then examined the effect of sex on DNA methylation with a multiple linear regression analysis after adjusting for age, the estimated 6 cell-type proportions, and the covariates identified in a surrogate variable analysis. We identified differential DNA methylation between males and females at 292 autosomal CpG site loci in the discovery set (Bonferroni-adjusted p < 0.05). Of these 292 CpG sites, significant sex differences were also observed at 98 sites in the replication set (p < 0.05). These findings provided further evidence that DNA methylation may play a role in the differentiation or maintenance of sexual dimorphisms. Our methylome mapping of the effects of sex may be useful to understanding the molecular mechanism involved in both normal development and diseases.


No association between the COMT Val158Met polymorphism and the long-term clinical response in obsessive-compulsive disorder in the Japanese population.

Catechol-O-methyltransferase (COMT) is an enzyme that participates in the metabolic inactivation of dopamine and norepinephrine, and the Met allele of the COMT Val158Met polymorphism is associated with lower enzymatic activity. The purpose of the present study was to investigate whether this functional variant is associated with obsessive-compulsive disorder (OCD) and the clinical responses in OCD. We first performed a case-control association study between the COMT Val158Met polymorphism and OCD (171 cases and 944 controls). Then, we examined the association between this polymorphism and the clinical responses in 91 of the OCD patients. Our study did not find a significant association between the Met allele and OCD risk or between the Met allele and clinical responses (p > 0.05). The present case-control/pharmacogenetic study did not provide clear evidence that the COMT Val158Met polymorphism is a predictor of OCD or of OCD patients' clinical responses.


Polymorphism in the promoter of the gene for the serotonin transporter affects the age of onset of major depressive disorder in the Japanese population.

Recent research has suggested that a functional polymorphism in the promoter region of the serotonin transporter gene (serotonin transporter-linked polymorphic region, 5HTTLPR) may be implicated in gene-environment interactions leading to major depressive disorder (MDD). Our study examined the association between 5HTTLPR and clinical variables of MDD in the Japanese population. We genotyped 5HTTLPR in 216 patients with MDD and 213 age- and sex-matched controls. The genotype distributions and allele frequencies were similar in the patients and controls. When the relationships between the polymorphism and several clinical variables (i.e., age of onset, number of episodes, presence of psychotic features, suicidal behavior, and family history) were examined, the dose of the long (l) allele had significant effects on the age of onset. These results suggest that 5HTTLPR may not be entirely related to the development of MDD but may be related to the age of onset of MDD, which may be due to gene-environment interactions in the Japanese population. Because of the low frequencies of psychotic features and suicidal behavior, our results must be treated with caution until they are replicated in larger numbers of Japanese samples. MDD patients did not undergo a structured interview. Clinical information from the medical records may have not been complete.


Biological tests for major depressive disorder that involve leukocyte gene expression assays.

Development of easy-to-use biological diagnostic tests for major depressive disorder (MDD) may facilitate MDD diagnosis and delivery of optimal treatment. Here, we examined leukocyte gene expression to develop a biological diagnostic test for MDD. 25 drug-naive MDD patients (MDDs) and 25 age- and sex-matched healthy subjects (Controls) participated in a pilot study. A subsequent replication study involved 20 MDDs and 18 Controls. We used custom-made PCR array plates to examine mRNA levels of 40 candidate genes in leukocyte samples to assess whether any combination of these genes could be used to differentiate MDDs from Controls based on expression profiles. Among 40 candidate genes, we identified a set of seven genes (PDGFC, SLC6A4, PDLIM5, ARHGAP24, PRNP, HDAC5, and IL1R2), each of which had expression levels that differed significantly between MDD and Control samples in the pilot study. To identify genes whose expression best differentiated between MDDs and Controls, a linear discriminant function was developed to discriminate between MDDs and Controls based on the standardized values of gene expression after Z-score transformation. Ultimately, five genes (PDGFC, SLC6A4, ARHGAP24, PRNP, and HDAC5) were selected for a multi-assay diagnostic test. In the pilot study, this diagnostic test demonstrated sensitivity and specificity of 80% and 92%, respectively. The replication study yielded nearly identical results, sensitivity of 85% and specificity of 89%. Using leukocyte gene expression profiles, we could differentiate MDDs from Controls with adequate sensitivity and specificity. Additional markers not yet identified might further improve the performance of this test.


Association of autism tendency and hemodynamic changes in the prefrontal cortex during facial expression stimuli measured by multi-channel near-infrared spectroscopy.

The aim of this study is to examine the hemodynamic changes induced by the cognitive process of facial expression by using multi-channel near-infrared spectroscopy in healthy subjects with varying degrees of autism tendency. Subjects were 38 volunteers, 20 men and 18 women. Autism tendency was measured by the Autism Spectrum Quotient. The hemodynamic changes in the prefrontal cortex were measured by 24-channel near-infrared spectroscopy system, while subjects were asked to judge their own emotional response to standardized pictures of eight kinds of facial expressions on a computer screen. There were significant negative correlations between Autism Spectrum Quotient scores and accuracy of fearful expression recognition as well as increases in the concentration of oxygenated hemoglobin in response to four kinds of emotional faces (fear, contempt, sadness and disgust). Our findings suggest that the greater tendency to autism that subjects have, the more difficulty they have in recognizing a fearful expression and the less hemodynamic change in the prefrontal cortex they show in response to negative facial expressions.


Blood diagnostic biomarkers for major depressive disorder using multiplex DNA methylation profiles: discovery and validation.

Aberrant DNA methylation in the blood of patients with major depressive disorder (MDD) has been reported in several previous studies. However, no comprehensive studies using medication-free subjects with MDD have been conducted. Furthermore, the majority of these previous studies has been limited to the analysis of the CpG sites in CpG islands (CGIs) in the gene promoter regions. The main aim of the present study is to identify DNA methylation markers that distinguish patients with MDD from non-psychiatric controls. Genome-wide DNA methylation profiling of peripheral leukocytes was conducted in two set of samples, a discovery set (20 medication-free patients with MDD and 19 controls) and a replication set (12 medication-free patients with MDD and 12 controls), using Infinium HumanMethylation450 BeadChips. Significant diagnostic differences in DNA methylation were observed at 363 CpG sites in the discovery set. All of these loci demonstrated lower DNA methylation in patients with MDD than in the controls, and most of them (85.7%) were located in the CGIs in the gene promoter regions. We were able to distinguish patients with MDD from the control subjects with high accuracy in the discriminant analysis using the top DNA methylation markers. We also validated these selected DNA methylation markers in the replication set. Our results indicate that multiplex DNA methylation markers may be useful for distinguishing patients with MDD from non-psychiatric controls.


Prefrontal activation during two Japanese Stroop tasks revealed with multi-channel near-infrared spectroscopy.

The Stroop task is sometimes used in psychiatric research to elicit prefrontal activity, which presumably reflects cognitive functioning. Although there are two Stroop tasks (Kana script and Kanji script) in Japan, it is unclear whether these tasks elicit the same hemoglobin changes. Moreover, it is unclear whether psychological conditions or characteristics influence hemoglobin changes in the Japanese Stroop task. The aim of this study was to clarify whether hemoglobin changes elicited by the two Japanese Stroop tasks accurately reflected cognitive functioning. Hemoglobin changes were measured with multi-channel near-infrared spectroscopy (NIRS) in 100 healthy Japanese participants performing two Japanese Stroop tasks. The Beck-Depression Inventory (BDI), State-Trait-Anxiety Inventory (STAI), and Maudsley Obsessive Compulsive Inventory (MOCI) were administered to participants to identify psychological conditions or personality characteristics. Compared with the Kanji task, the Kana task produced a greater Stroop effect and a larger increase in oxyhemoglobin (oxy-Hb) concentration. Moreover there were no significant correlations between oxy-Hb concentration and BDI, STAI-trait, STAI-state, or MOCI scores. Therefore we found that a participant's psychological conditions or characteristics did not influence the hemodynamic changes during either task. These data suggest the Kana Stroop task is more useful than the Kanji Stroop task for NIRS studies in psychiatric research.

The Journal of Medical Investigation : JMI


Risk of bipolar disorder and psychotic features in patients initially hospitalised with severe depression.

Severe depression may be a risk factor for diagnostic conversion into bipolar disorder (BD), and psychotic depression (PD) has been consistently associated with BD. The aims of the present study were to investigate the stability of the diagnosis of severe depression and the differences between PD and non-psychotic severe depression (non-PD), as well as to assess the effectiveness of electroconvulsive therapy (ECT). Patients who were hospitalised for severe depression (diagnosed according to ICD-10) both with and without psychotic symptoms (n=89; mean age=55.6 years, SD=13.9) from 2001 to 2010 were retrospectively assessed. By the 75th month of follow-up assessments, 11(12.4%) patients had developed BD. Among these 11 converters, nine had developed BD within 1 year after admission. Only sub-threshold hypomanic symptoms were significantly related to developing BD. The number of depressive episodes and history of physical diseases were significantly increased in non-PD compared with PD patients, whereas ECT was significantly increased in PD compared with non-PD patients. There was a significant association between length of stay at the hospital and the number of days between admission and ECT. Sub-threshold hypomanic symptoms may represent a prodrome of BD or an indicator of an already manifest phenotype, especially in older patients, which suggests cautious use of antidepressants. In severe depression, non-PD may often occur secondary to physical diseases and patients may experience increased recurrences compared with PD patients, which may be a more 'primary' disorder and often requires ECT treatments. ECT is effective for severe depression regardless of the presence of any psychotic feature; the earlier ECT is introduced, the better the expected treatment outcome.


Changes in plasma d-serine, l-serine, and glycine levels in treatment-resistant schizophrenia before and after clozapine treatment.

Hypofunction of the N-methyl-d-aspartate (NMDA) subtype of glutamate receptors may be involved in the pathophysiology of schizophrenia. Many studies have investigated peripheral NMDA receptor-related glutamatergic amino acid levels because of their potential as biological markers. Peripheral d-serine levels and the ratio of d-serine to total serine have been reported to be significantly lower in patients with schizophrenia than in controls. Peripheral d-serine levels and the d-/l-serine ratio have also been reported to significantly increase in patients with schizophrenia as their clinical symptoms improve from the time of admission to the time of discharge. In this study, we examined whether peripheral NMDA receptor-related glutamatergic amino acids levels were altered in patients with treatment-resistant schizophrenia compared to controls and whether these peripheral amino acids levels were altered by clozapine treatment. Twenty-two patients with treatment-resistant schizophrenia and 22 age- and gender-matched healthy controls were enrolled. The plasma levels of d-serine, l-serine, glycine, glutamate, and glutamine were measured before and after clozapine treatment. We found that the plasma levels of d-serine and the d-/l-serine ratio were significantly lower in the patients before clozapine treatment than in the controls. The d-/l-serine ratio was significantly increased by clozapine treatment in patients, and no significant difference was observed in the plasma levels of d-serine and the d-/l-serine ratio between the patients after clozapine treatment and the controls. We also found that plasma glycine levels and the glycine/l-serine ratio were significantly increased following clozapine treatment in the patients, and the glycine/l-serine ratio was significantly higher in the patients after clozapine treatment than in the controls. There was no significant difference in the plasma levels of glutamate and glutamine both between the controls and patients and between before and after clozapine treatment. This study firstly demonstrated changes of d-/l-serine and glycine/l-serine ratio between before and after clozapine treatment, suggesting that the plasma d-/l-serine ratio and glycine/l-serine ratio could be markers of therapeutic efficacy or clinical state in treatment-resistant schizophrenia.


Neuropsychological and psychiatric assessments following bilateral deep brain stimulation of the subthalamic nucleus in Japanese patients with Parkinson's disease.

The physical benefits of subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) patients are well documented, but the mental benefits are uncertain, particularly in Japanese patients. This study evaluated the clinical and neuropsychological characteristics before and after STN-DBS surgery in Japanese PD patients. PD patients (n=13, age 67.0 ± 7.8 years) were evaluated pre-surgery (baseline) and at 1 and 6 months post-surgery by two trained psychiatrists. The motor symptoms were assessed by the Unified Parkinson's Disease Rating Scale (UPDRS) motor score. The neuropsychological and psychiatric tests performed were the Mini-Mental State Examination, the Wisconsin Card Sorting Test (WCST), the Verbal Fluency Test (VFT), the Hamilton Depression Rating Scale and the Hamilton Anxiety Rating Scale (HAM-A). The UPDRS motor score (p<0.001) and HAM-A score (p=0.004) showed significant improvement at 1 month post-surgery, but a significant decline was observed in the WCST total error (p=0.005) and the semantic VFT score (p<0.001). The phonetic VFT also showed a substantial decline (p=0.015) at 1 month post-surgery. At 6 months post-surgery, the improvement in the UPDRS motor score was maintained, and the scores on the neuropsychological and psychiatric tests had returned to baseline. Although bilateral STN-DBS did not appear to have long-term effects on neuropsychological and psychiatric outcomes, the microlesion effects associated with STN-DBS appear to increase the risk of transient cognitive and psychiatric complications. These complications should be monitored by careful observation of neurological and psychiatric symptoms.


Meta-analyses of Blood Homocysteine Levels for Gender and Genetic Association Studies of the MTHFR C677T Polymorphism in Schizophrenia.

Previous studies suggest that elevated blood homocysteine levels and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism are risk factors for schizophrenia. However, the effects of gender and MTHFR C677T genotypes on blood homocysteine levels in schizophrenia have not been consistent. We first investigated whether plasma total homocysteine levels were higher in patients with schizophrenia than in controls with stratification by gender and by the MTHFR C677T genotypes in a large cohort (N = 1379). Second, we conducted a meta-analysis of association studies between blood homocysteine levels and schizophrenia separately by gender (N = 4714). Third, we performed a case-control association study between the MTHFR C677T polymorphism and schizophrenia (N = 4998) and conducted a meta-analysis of genetic association studies based on Japanese subjects (N = 10 378). Finally, we assessed the effect of plasma total homocysteine levels on schizophrenia by a mendelian randomization approach. The ANCOVA after adjustment for age demonstrated a significant effect of diagnosis on the plasma total homocysteine levels in all strata, and the subsequent meta-analysis for gender demonstrated elevated blood homocysteine levels in both male and female patients with schizophrenia although antipsychotic medication might influence the outcome. The meta-analysis of the Japanese genetic association studies demonstrated a significant association between the MTHFR C677T polymorphism and schizophrenia. The mendelian randomization analysis in the Japanese populations yielded an OR of 1.15 for schizophrenia per 1-SD increase in plasma total homocysteine. Our study suggests that increased plasma total homocysteine levels may be associated with an increased risk of schizophrenia.


No abnormal hexanucleotide repeat expansion of C9ORF72 in Japanese schizophrenia patients.

Abnormal hexanucleotide repeat expansion of C9ORF72 is known to cause neurodegenerative disorders such as frontotemporal dementia. Additionally, patients with psychotic symptoms are more likely to have abnormal hexanucleotide repeat expansion than are patients without them. We investigated the hexanucleotide repeat sizes of C9ORF72 in 466 Japanese schizophrenia patients. We found no abnormal hexanucleotide repeat expansion. In conclusion, C9ORF72 may not be responsible for schizophrenia susceptibility in the Japanese population.


Missense variants of the alanine:glyoxylate aminotransferase 2 gene are not associated with Japanese schizophrenia patients.

Alanine:glyoxylate aminotransferase 2 (AGXT2) is the only enzyme that degrades D-3-aminoisobutyrate (D-AIB), which is an intermediate product of thymine, and 30-40% of Japanese lack AGXT2 activity genetically and excrete high amounts of D-AIB in their urine. Recently, AGXT2 is reported to metabolize asymmetric dimethyl arginine (ADMA), a competitive inhibitor of nitric oxide (NO) synthase. Since AGXT2 is expressed in the central nervous system, the loss of AGXT2 activity will be related to the vulnerability for neuropsychiatric disorders related to the NO system. In this study, we recruited 85 Japanese subjects to discover loss variants of the AGXT2 gene with the amount of D-AIB excretion in their urine. From the statistical relevance between them, we found three missense polymorphisms (rs37370, rs37369, and rs180749) independently related to AGXT2 activity (P<0.0001). Then, we performed a case-control association analysis of its missense polymorphisms with 1136 schizophrenia and 1908 control subjects because the NO system may be involved in the vulnerability of schizophrenia processes. We could not find any associations of three functional SNPs with schizophrenia pathogenesis in the analyses of either genotypic or allelic models. We concluded that the AGXT2 gene is not associated with schizophrenia in Japanese subjects.

Progress in Neuro-Psychopharmacology & Biological Psychiatry