DNA Methylation Profiles of the DRD2 and NR3C1 Genes in Patients with Recent-Onset Psychosis.

Objectives: Dopamine receptor D2 gene (DRD2) and glucocorticoid receptor gene (NR3C1) are implicated in the development of psychosis. We investigated methylation levels of DRD2 and NR3C1 in peripheral blood of patients with recent-onset (RO) psychosis using bisulfite pyrosequencing as well as its association with childhood trauma and rumination. Methods: In all, 51 individuals with RO psychosis and 47 healthy controls were recruited. DNA methylation levels in the targeted regions of two genes were analyzed and compared. Childhood trauma and rumination were evaluated using the Early Trauma Inventory Self-Report Short Form (ETI-SF) and Brooding Scale (BS), respectively. Correlations between the scores of the ETI-SF and BS and methylation levels were explored. Results: For DRD2, we found no significant differences between groups in terms of methylation level or association with childhood trauma or rumination. For NR3C1, we found a trend level significance for average value of all CpG sites and significant hypermethylation or hypomethylation at specific sites. There was also a significant positive correlation between the methylation level at the CpG8 site of NR3C1 exon 1F and negative symptom subscale score of the PANSS (PANSS-N). Conclusion: Epigenetic alterations of NR3C1 are associated with the pathophysiology of psychosis. Further epigenetic studies will elucidate the molecular mechanisms underpinning the pathophysiology of psychosis.

Methylome-wide Association Study of Patients with Recent-onset Psychosis.

Objective: Dysregulation of gene expression through epigenetic mechanisms may have a vital role in the pathogenesis of schizophrenia (SZ). In this study, we investigated the association of altered methylation patterns with SZ symptoms and early trauma in patients and healthy controls. Methods: The present study was conducted to identify methylation changes in CpG sites in peripheral blood associated with recent-onset (RO) psychosis using methylome-wide analysis. Lifestyle factors, such as smoking, alcohol, exercise, and diet, were controlled. Results: We identified 2,912 differentially methylated CpG sites in patients with RO psychosis compared to controls. Most of the genes associated with the top 20 differentially methylated sites had not been reported in previous methylation studies and were involved in apoptosis, autophagy, axonal growth, neuroinflammation, protein folding, etc. The top 15 significantly enriched Kyoto Encyclopedia of Genes and Genomes pathways included the oxytocin signaling pathway, long-term depression pathway, axon guidance, endometrial cancer, long-term potentiation, mitogen-activated protein kinase signaling pathway, and glutamatergic pathway, among others. In the patient group, significant associations of novel methylated genes with early trauma and psychopathology were observed. Conclusion: Our results suggest an association of differential DNA methylation with the pathophysiology of psychosis and early trauma. Blood DNA methylation signatures show promise as biomarkers of future psychosis.

Development of the Korea-Polyenvironmental Risk Score for Psychosis.

OBJECTIVE: Comprehensive understanding of polyenvironmental risk factors for the development of psychosis is important. Based on a review of related evidence, we developed the Korea Polyenvironmental Risk Score (K-PERS) for psychosis. We investigated whether the K-PERS can differentiate patients with schizophrenia spectrum disorders (SSDs) from healthy controls (HCs). METHODS: We reviewed existing tools for measuring polyenvironmental risk factors for psychosis, including the Maudsley Environmental Risk Score (ERS), polyenviromic risk score (PERS), and Psychosis Polyrisk Score (PPS). Using odds ratios and relative risks for Western studies and the "population proportion" (PP) of risk factors for Korean data, we developed the K-PERS, and compared the scores thereon between patients with SSDs and HCs. In addition, correlation was performed between the K-PERS and Positive and Negative Syndrome Scale (PANSS). RESULTS: We first constructed the "K-PERS-I," comprising five factors based on the PPS, and then the "K-PERS-II" comprising six factors based on the ERS. The instruments accurately predicted participants' status (case vs. control). In addition, the K-PERS-I and -II scores exhibited significant negative correlations with the negative symptom factor score of the PANSS. CONCLUSION: The K-PERS is the first comprehensive tool developed based on PP data obtained from Korean studies that measures polyenvironmental risk factors for psychosis. Using pilot data, the K-PERS predicted patient status (SSD vs. HC). Further research is warranted to examine the relationship of K-PERS scores with clinical outcomes of psychosis and schizophrenia.

Comparison of clinical features and 1-year outcomes between patients with psychotic disorder not otherwise specified and those with schizophrenia.

AIM: Research on psychotic disorder not otherwise specified (PNOS) that clearly mentions its subgroups is very rare. This study was conducted to identify the demographic and clinical features, cognitive function, and 1-year outcomes of patients with early stage PNOS compared with those with early stage schizophrenia (SZ). METHODS: The study subjects were 54 and 321 patients with PNOS and SZ, respectively, who were registered at least more than 1 year ago. Due to drop out, only 37 and 210 patients with PNOS and SZ were evaluated at the 1-year follow-up. We compared clinical variables (duration of untreated psychosis, symptom severity, self-rating scales, and so on), cognitive function, and short-term outcomes (treatment response, remission, compliance, drop out, relapse) between the two groups. RESULTS: The patients with PNOS were associated with higher diagnostic stability (53.7%) compared with those in previous studies. They had lower symptom severity, better treatment response at 2 months and higher remission rates at 12 months, but poorer compliance at 6 months compared with patients with SZ. Level of cognitive impairment in PNOS was intermediate between those of SZ patients and healthy controls. CONCLUSIONS: These findings indicate that PNOS has unique clinical features, suggesting that it should be treated as a distinct clinical syndrome. At the same time, however, prevention of its possible progression to other psychotic disorders in some patients with PNOS is also important.

Symptomatic and full remission rates in first-episode psychosis: A 12-month follow-up study in Korea.

AIM: In the present study, the prevalence and predictors of symptomatic and full remission were investigated in patients with first-episode psychosis (FEP) at the 12-month follow-up. METHODS: A total of 308 participants aged 18-45 years fulfilled the study inclusion criteria and 214 completed the 12-month follow-up. RESULTS: At the 12-month follow-up, 67.3% (142) and 25.9% (55) of the FEP patients met the criteria for symptomatic and full remission, respectively. Stepwise logistic regression analysis showed a shorter duration of untreated psychosis (DUP), no family history, lower Positive and Negative Syndrome Scale (PANSS) negative symptom scores at baseline and higher familial support predicted symptomatic remission at the 12-month follow-up. A higher educational level, shorter DUP, lower PANSS general symptoms scores at baseline and higher subjective well-being under neuroleptics emotional regulation scores predicted full remission. CONCLUSIONS: Our findings regarding the rates of symptomatic and full remission are consistent with previous studies. The results indicate a large discrepancy between symptomatic versus full remission rates at a 12-month follow-up in patients with FEP. Effective psychosocial interventions are necessary to improve the outcomes of FEP patients.

Longitudinal symptom network structure in first-episode psychosis: a possible marker for remission.

BACKGROUND: Network approach has been applied to a wide variety of psychiatric disorders. The aim of the present study was to identify network structures of remitters and non-remitters in patients with first-episode psychosis (FEP) at baseline and the 6-month follow-up. METHODS: Participants (n = 252) from the Korean Early Psychosis Study (KEPS) were enrolled. They were classified as remitters or non-remitters using Andreasen's criteria. We estimated network structure with 10 symptoms (three symptoms from the Positive and Negative Syndrome Scale, one depressive symptom, and six symptoms related to schema and rumination) as nodes using a Gaussian graphical model. Global and local network metrics were compared within and between the networks over time. RESULTS: Global network metrics did not differ between the remitters and non-remitters at baseline or 6 months. However, the network structure and nodal strengths associated with positive-self and positive-others scores changed significantly in the remitters over time. Unique central symptoms for remitters and non-remitters were cognitive brooding and negative-self, respectively. The correlation stability coefficients for nodal strength were within the acceptable range. CONCLUSION: Our findings indicate that network structure and some nodal strengths were more flexible in remitters. Negative-self could be an important target for therapeutic intervention.

Network analysis of trauma in patients with early-stage psychosis.

Childhood trauma (ChT) is a risk factor for psychosis. Negative lifestyle factors such as rumination, negative schemas, and poor diet and exercise are common in psychosis. The present study aimed to perform a network analysis of interactions between ChT and negative lifestyle in patients and controls. We used data of patients with early-stage psychosis (n = 500) and healthy controls (n = 202). Networks were constructed using 12 nodes from five scales: the Brief Core Schema Scale (BCSS), Brooding Scale (BS), Dietary Habits Questionnaire, Physical Activity Rating, and Early Trauma Inventory Self Report-Short Form (ETI). Graph metrics were calculated. The nodes with the highest predictability and expected influence in both patients and controls were cognitive and emotional components of the BS and emotional abuse of the ETI. The emotional abuse was a mediator in the shortest pathway connecting the ETI and negative lifestyle for both groups. The negative others and negative self of the BCSS mediated emotional abuse to other BCSS or BS for patients and controls, respectively. Our findings suggest that rumination and emotional abuse were central symptoms in both groups and that negative others and negative self played important mediating roles for patients and controls, respectively.Trial Registration: ClinicalTrials.gov identifier: CUH201411002.

Effects of Stathmin 1 Gene Knockout on Behaviors and Dopaminergic Markers in Mice Exposed to Social Defeat Stress.

Stathmin (STMN), a microtubule-destabilizing factor, can regulate fear, anxiety, and learning. Social defeat stress (SDS) has detrimental effects on mental health and increases the risk of various psychiatric diseases. This study investigated the effects of STMN1 gene knockout (KO) on behavioral parameters and dopaminergic markers using an SDS mouse model. The STMN1 KO mice showed anxious hyperactivity, impaired object recognition, and decreased levels of neutral and social investigating behaviors at baseline compared to wild-type (WT) mice. The impact of SDS on neutral, social investigating and dominant behaviors differed markedly between the STMN1 WT and KO mice. In addition, different levels of total DARPP-32 and pDARPP-32 Thr75 expression were observed among the control, unsusceptible, and susceptible groups of STMN1 KO mice. Our results show that STMN1 has specific roles in locomotion, object recognition, and social interactions. Moreover, SDS had differential impacts on social interactions and dopaminergic markers between STMN1 WT and KO mice.

Negative Schema and Rumination as Mediators of the Relationship Between Childhood Trauma and Recent Suicidal Ideation in Patients With Early Psychosis.

OBJECTIVE: High rates of childhood trauma and adult suicidality have been reported in patients who have schizophrenia. This study sought to explore mediators between childhood trauma and suicidality in adulthood to help determine therapeutic approaches. METHODS: This study included 314 adult patients with early psychosis who were participants in the Korean Early Psychosis Cohort Study, which was a prospective naturalistic observational cohort study started in December 2014. DSM-5 criteria were used to assign the diagnosis of schizophrenia spectrum and other psychotic disorders. Cross-sectional data obtained at baseline were used for analysis. The Early Trauma Inventory Self Report-Short Form and the Columbia Suicide Severity Rating Scale were employed to collect data on childhood trauma and suicidal ideation and attempts. Other measures were used to evaluate depression, empathy, psychopathology, and rumination. RESULTS: A total of 90.1% of the participants experienced at least 1 childhood traumatic event. The rates of significant` physical punishment, emotional abuse, and sexual events were 37.3%, 35.6%, and 6.4%, respectively. The rates of recent suicidal ideation and attempts were 32.0% and 10.0%, respectively. Independent predictors of recent suicidal ideation included depression, negative schema, and rumination. Furthermore, negative schema and rumination played partial or full mediating roles in the relationship between childhood trauma and recent suicidal ideation. CONCLUSIONS: These findings highlight the importance of performing careful evaluations of childhood trauma and suicidality and of developing effective strategies to reduce mediating factors that may be amenable to psychosocial approaches.

Metabolite signature associated with stress susceptibility in socially defeated mice.

OBJECTIVE: Social defeat represents a naturalistic form of conditioned fear and is often used as an animal model of depression. The present study aimed to identify the neurochemicals in select brain regions of mice exposed to social defeat stress. METHODS: Adult C57BL/6N mice were subjected social defeat stress for 10 days. Using high-resolution magic angle spinning 1H nuclear magnetic resonance (HR-MAS 1H NMR), untargeted metabolomes were measured in the amygdala (AMY), dorsal hippocampus (dHIP), dorsal striatum (dST), and prefrontal cortex (PFC). RESULTS: We observed perturbations of glutamine in the AMY; glutamate in the dHIP; glycine and myo-inositol in the dST; and aspartate, choline, and phosphoethanolamine in the PFC of susceptible and/or unsusceptible groups compared to the control group. The susceptible and unsusceptible groups significantly differed with regard to three metabolites: glutamine, glycine, and choline. CONCLUSION: These findings suggest that social defeat stress induces disturbances in the metabolism of amino acids, lipids, and neurotransmitters in several brain areas. The resulting susceptibility-related metabolites may provide new insights into the pathophysiology underlying stress-related mental illness.