The effect of education regarding treatment guidelines for schizophrenia and major depressive disorders on psychiatrists' hypnotic medication prescribing behavior: a multicenter study.

BACKGROUND: To examine whether the "Effectiveness of Guideline for Dissemination and Education in psychiatric treatment (EGIUDE)" project affects the rate of prescriptions of hypnotic medication and the type of hypnotic medications prescribed among psychiatrists, for schizophrenia and major depressive disorder in Japan. METHODS: The EGUIDE project is a nationwide prospective study of evidence-based clinical guidelines for schizophrenia and major depressive disorder in Japan. From 2016 to 2021, clinical and prescribing data from patients discharged from hospitals participating in the EGUIDE project were used to examine hypnotic medication prescriptions The prescribing rate of hypnotics and the prescribing rate of each type of hypnotic (benzodiazepine receptor agonist, nonbenzodiazepine receptor agonist, melatonin receptor agonist, and orexin receptor antagonist) were compared among patients who had been prescribed medication by psychiatrists participating in the EGUIDE project and patients who had been prescribed medication by nonparticipating psychiatrists. Multivariate logistic regression analysis was performed to examine the effect of the EGUIDE project on the prescription of hypnotic medications. RESULTS: A total of 12,161 patients with schizophrenia and 6,167 patients with major depressive disorder were included. Psychiatrists participating in the EGUIDE project significantly reduced the rate of prescribing hypnotic medication and benzodiazepine receptor agonists for both schizophrenia (P < 0.001) and major depressive disorder (P < 0.001) patients. CONCLUSION: This is the first study to investigate the educational effects of guidelines for the treatment of psychiatric disorders on psychiatrists in terms of prescribing hypnotic medications to patients. The EGUIDE project may play an important role in reducing hypnotic medication prescription rates, particularly with respect to benzodiazepine receptor agonists. The results suggest that the EGUIDE project may result in improved therapeutic behavior.

Combination Psychotropic Use for Schizophrenia With Long-Acting Injectable Antipsychotics and Oral Antipsychotics: A Nationwide Real-World Study in Japan.

BACKGROUND: Although several guidelines recommend monotherapy with antipsychotics for the treatment of schizophrenia, patients who receive long-acting injectable antipsychotics (LAIs) are frequently treated with oral antipsychotics (OAPs). In the present study, we investigated the detailed use of psychotropic medications among patients throughout Japan with schizophrenia who received LAIs or OAPs. METHODS: The present study used data from the project for the Effectiveness of Guidelines for Dissemination and Education in psychiatric treatment from 94 facilities in Japan. The LAI group included patients who received any LAI, and the non-LAI group included patients who took only OAP medications at discharge. The participants of this study were 2518 schizophrenia patients (263 in the LAI group and 2255 in the non-LAI group) who received inpatient treatment and had prescription information at discharge between 2016 and 2020. RESULTS: This study revealed significantly higher rates of polypharmacy antipsychotics, number of antipsychotics, and chlorpromazine equivalents in the LAI group than in the non-LAI group. In contrast, the LAI group showed lower rate of concomitant use of hypnotic and/or antianxiety medication than the non-LAI group. CONCLUSIONS: Presenting these real-world clinical results, we want to encourage clinicians to keep monotherapy in mind for the treatment of schizophrenia, especially by reducing concomitant use of antipsychotics in the LAI group and reducing hypnotic and/or antianxiety medication in the non-LAI group.

Generalizable brain network markers of major depressive disorder across multiple imaging sites.

Many studies have highlighted the difficulty inherent to the clinical application of fundamental neuroscience knowledge based on machine learning techniques. It is difficult to generalize machine learning brain markers to the data acquired from independent imaging sites, mainly due to large site differences in functional magnetic resonance imaging. We address the difficulty of finding a generalizable marker of major depressive disorder (MDD) that would distinguish patients from healthy controls based on resting-state functional connectivity patterns. For the discovery dataset with 713 participants from 4 imaging sites, we removed site differences using our recently developed harmonization method and developed a machine learning MDD classifier. The classifier achieved an approximately 70% generalization accuracy for an independent validation dataset with 521 participants from 5 different imaging sites. The successful generalization to a perfectly independent dataset acquired from multiple imaging sites is novel and ensures scientific reproducibility and clinical applicability.

Effects of electroconvulsive therapy on the use of anxiolytics and sleep medications: a propensity score-matched analysis.

AIM: We investigated the association of electroconvulsive therapy (ECT) with anxiolytic and sleep medication use in patients with major depressive disorder (MDD) and schizophrenia (SZ). METHODS: This nationwide observational study analyzed data from 3483 MDD inpatients and 6663 SZ inpatients. Patients with MDD and SZ were classified into those who underwent ECT during hospitalization and those who did not. A propensity score-matching method was performed to adjust for preadmission characteristics and clinical information, which were expected bias between the two groups. Rates of anxiolytic and sleep medication use at discharge were compared in the matched sample. RESULTS: 500 MDD patients were assigned to both groups. In the matched MDD sample, the rate of anxiolytic and sleep medication use at discharge was significantly lower in the ECT group than in the non-ECT group (64.9% vs. 75.8%, P = 1.7 × 10-4 ). In the ECT group, the rate of anxiolytic and sleep medication use at discharge was significantly lower than that prior to admission (64.9% vs. 73.2%, P = 1.2 × 10-14 ). 390 SZ patients were allocated. In the matched SZ sample, the ECT group was not significantly different from the non-ECT group in the rate of anxiolytics and sleep medications use at discharge (61.3% vs. 68.2%, P = 4.3 × 10-2 ). In the ECT group, the rate of anxiolytics and sleep medications use at discharge was significantly lower than that before admission (61.3% vs. 70.5%, P = 4.4 × 10-4 ), although this was not the primary outcome. CONCLUSION: Reduction of anxiolytic and sleep medication use may be considered positively when ECT is indicated for treatment of MDD.

Effect of education regarding treatment guidelines for schizophrenia and depression on the treatment behavior of psychiatrists: A multicenter study.

AIM: This study aims to examine the real-world effectiveness of education regarding clinical guidelines for psychiatric disorders using 'the Effectiveness of guidelines for dissemination and education in psychiatric treatment (EGUIDE)' project. METHODS: The EGUIDE project is a nationwide prospective implementation study of two clinical practice guidelines, i.e., the Guideline for Pharmacological Therapy of Schizophrenia and the Treatment Guidelines for Major Depressive Disorders, in Japan. Between 2016 and 2019, 782 psychiatrists belonging to 176 hospitals with psychiatric wards participated in the project and attended lectures on clinical practice guidelines. The proportions of guideline-recommended treatments in 7405 patients with schizophrenia and 3794 patients with major depressive disorder at participating hospitals were compared between patients under the care of psychiatrists participating in the project and those not participating in the project. Clinical and prescribing data on the patients discharged from April to September each year from participating hospitals of the project were also analyzed. RESULTS: The proportions of three quality indicators (antipsychotic monotherapy regardless of whether other psychotropics medication, antipsychotic monotherapy without other psychotropics and no prescription of anxiolytics or hypnotics) for schizophrenia were higher among participating psychiatrists than among nonparticipating psychiatrists. As similar results were obtained in major depressive disorder, the effectiveness of the project for the dissemination of guideline-recommended treatment has been replicated. CONCLUSION: This strategy of providing education regarding the clinical guidelines for psychiatric disorders was effective in improving the treatment-related behavior of psychiatrists. The use of this education-based strategy might contribute to resolving the mental health treatment gap.

Harmonization of resting-state functional MRI data across multiple imaging sites via the separation of site differences into sampling bias and measurement bias.

When collecting large amounts of neuroimaging data associated with psychiatric disorders, images must be acquired from multiple sites because of the limited capacity of a single site. However, site differences represent a barrier when acquiring multisite neuroimaging data. We utilized a traveling-subject dataset in conjunction with a multisite, multidisorder dataset to demonstrate that site differences are composed of biological sampling bias and engineering measurement bias. The effects on resting-state functional MRI connectivity based on pairwise correlations because of both bias types were greater than or equal to psychiatric disorder differences. Furthermore, our findings indicated that each site can sample only from a subpopulation of participants. This result suggests that it is essential to collect large amounts of neuroimaging data from as many sites as possible to appropriately estimate the distribution of the grand population. Finally, we developed a novel harmonization method that removed only the measurement bias by using a traveling-subject dataset and achieved the reduction of the measurement bias by 29% and improvement of the signal-to-noise ratios by 40%. Our results provide fundamental knowledge regarding site effects, which is important for future research using multisite, multidisorder resting-state functional MRI data.

The characteristics of discharge prescriptions including pro re nata psychotropic medications for patients with schizophrenia and major depressive disorder from the survey of the "Effectiveness of guidelines for dissemination and education in psychiatric treatment (EGUIDE)" project.

BACKGROUND: Several guidelines recommend monotherapy in pharmacotherapy for schizophrenia and major depressive disorder. The content of regular prescriptions has been reported in several studies, but not enough research has been conducted on the content of pharmacotherapy, including pro re nata (PRN) medications. The purpose of this study was to evaluate the content of pharmacotherapy, including PRN medications, and to clarify the relationship with regular prescriptions. METHODS: We used data from the "Effectiveness of Guidelines for Dissemination And Education in psychiatric treatment" (EGUIDE) project to investigate the presence or absence of PRN psychotropic medications at discharge for each drug category. We compared the PRN psychotropic prescription ratio at discharge by diagnosis for each drug category. The antipsychotic monotherapy ratio and no prescription ratio of other psychotropics for schizophrenia at discharge and the antidepressant monotherapy ratio and no prescription ratio of other psychotropics for major depressive disorder at discharge were calculated for each regular prescription, including PRN psychotropic medications, as quality indicators (QIs). Spearman's rank correlation test was performed for QI values of regular prescriptions and the QI ratio between regular prescriptions and prescriptions including PRN medications for each diagnosis. RESULTS: The PRN psychotropic prescription ratio at discharge was 28.7% for schizophrenia and 30.4% for major depressive disorder, with no significant differences by diagnosis. The prescription ratios of PRN antipsychotic medications and PRN antiparkinsonian medications were significantly higher for schizophrenia. The prescription ratios of PRN anxiolytic and hypnotic and PRN antidepressant medications were significantly higher for patients with major depressive disorder. For both schizophrenia and major depressive disorder, the QI was lower for discharge prescriptions, including PRN medications, than for regular prescriptions. QI values for regular prescriptions and the QI ratio were positively correlated. CONCLUSIONS: Considering PRN psychotropic medications, the monotherapy ratio and no prescription ratio of other psychotropics at discharge decreased in pharmacotherapy for schizophrenia and major depressive disorder. A higher ratio of monotherapy and no prescription of other psychotropics on regular prescriptions may result in less concomitant use of PRN psychotropic medications. Further studies are needed to optimize PRN psychotropic prescriptions.

Characterization of the signature of peripheral innate immunity in women with later-life major depressive disorder.

The prevalence of depression in later life is higher in women than in men. However, the sex difference in the pathophysiology of depression in elderly patients is not fully understood. Here, we performed gene expression profiling in leukocytes of middle-aged and elderly patients with major depressive disorder, termed later-life depression (LLD) in this context, and we characterized the sex-dependent pathophysiology of LLD. A microarray dataset obtained from leukocytes of patients (aged ≥50 years) with LLD (32 males and 39 females) and age-matched healthy individuals (20 males and 24 females) was used. Differentially expressed probes were determined by comparing the expression levels between patients and healthy individuals, and then functional annotation analyses (Ingenuity Pathway Analysis, Reactome pathway analysis, and cell-type enrichment analysis) were performed. A total of 1656 probes were differentially expressed in LLD females, but only 3 genes were differentially expressed in LLD males. The differentially expressed genes in LLD females were relevant to leukocyte extravasation signaling, Tec kinase signaling and the innate immune response. The upregulated genes were relevant to myeloid lineage cells such as CD14+ monocytes. In contrast, the downregulated genes were relevant to CD4+ and CD8+ T cells. Remarkable innate immune signatures are present in the leukocytes of LLD females but not males. Because inflammation is involved in the pathophysiology of depression, the altered inflammatory activity may be involved in the pathophysiology of LLD in women. In contrast, abnormal inflammation may be an uncommon feature in LLD males.

Distinctive Neuroanatomical Substrates for Depression in Bipolar Disorder versus Major Depressive Disorder.

No neuroanatomical substrates for distinguishing between depression of bipolar disorder (dBD) and major depressive disorder (dMDD) are currently known. The aim of the current multicenter study was to identify neuroanatomical patterns distinct to depressed patients with the two disorders. Further analysis was conducted on an independent sample to enable generalization of results. We directly compared MR images of these subjects using voxel-based morphometry (VBM) and a support vector machine (SVM) algorithm using 1531 participants. The VBM analysis showed significantly reduced gray matter volumes in the bilateral dorsolateral prefrontal (DLPFC) and anterior cingulate cortices (ACC) in patients with dBD compared with those with dMDD. Patients with the two disorders shared small gray matter volumes for the right ACC and left inferior frontal gyrus when compared with healthy subjects. Voxel signals in these regions during SVM analysis contributed to an accurate classification of the two diagnoses. The VBM and SVM results in the second cohort also supported these results. The current findings provide new evidence that gray matter volumes in the DLPFC and ACC are core regions in displaying shared and distinct neuroanatomical substrates and can shed light on elucidation of neural mechanism for depression within the bipolar/major depressive disorder continuum.

Epigenetic mechanisms of major depression: Targeting neuronal plasticity.

Major depressive disorder is one of the most common mental illnesses as it affects more than 350 million people globally. Major depressive disorder is etiologically complex and disabling. Genetic factors play a role in the etiology of major depression. However, identical twin studies have shown high rates of discordance, indicating non-genetic mechanisms as well. For instance, stressful life events increase the risk of depression. Environmental stressors also induce stable changes in gene expression within the brain that may lead to maladaptive neuronal plasticity in regions implicated in disease pathogenesis. Epigenetic events alter the chromatin structure and thus modulate expression of genes that play a role in neuronal plasticity, behavioral response to stress, depressive behaviors, and response to antidepressants. Here, we review new information regarding current understanding of epigenetic events that may impact depression. In particular, we discuss the roles of histone acetylation, DNA methylation, and non-coding RNA. These novel mechanisms of action may lead to new therapeutic strategies for treating major depression.

Genetic Demonstration of a Role for Stathmin in Adult Hippocampal Neurogenesis, Spinogenesis, and NMDA Receptor-Dependent Memory.

Neurogenesis and memory formation are essential features of the dentate gyrus (DG) area of the hippocampus, but to what extent the mechanisms responsible for both processes overlap remains poorly understood. Stathmin protein, whose tubulin-binding and microtubule-destabilizing activity is negatively regulated by its phosphorylation, is prominently expressed in the DG. We show here that stathmin is involved in neurogenesis, spinogenesis, and memory formation in the DG. tTA/tetO-regulated bitransgenic mice, expressing the unphosphorylatable constitutively active Stathmin4A mutant (Stat4A), exhibit impaired adult hippocampal neurogenesis and reduced spine density in the DG granule neurons. Although Stat4A mice display deficient NMDA receptor-dependent memory in contextual discrimination learning, which is dependent on hippocampal neurogenesis, their NMDA receptor-independent memory is normal. Confirming NMDA receptor involvement in the memory deficits, Stat4A mutant mice have a decrease in the level of synaptic NMDA receptors and a reduction in learning-dependent CREB-mediated gene transcription. The deficits in neurogenesis, spinogenesis, and memory in Stat4A mice are not present in mice in which tTA/tetO-dependent transgene transcription is blocked by doxycycline through their life. The memory deficits are also rescued within 3 d by intrahippocampal infusion of doxycycline, further indicating a role for stathmin expressed in the DG in contextual memory. Our findings therefore point to stathmin and microtubules as a mechanistic link between neurogenesis, spinogenesis, and NMDA receptor-dependent memory formation in the DG. SIGNIFICANCE STATEMENT: In the present study, we aimed to clarify the role of stathmin in neuronal and behavioral functions. We characterized the neurogenic, behavioral, and molecular consequences of the gain-of-function stathmin mutation using a bitransgenic mouse expressing a constitutively active form of stathmin. We found that stathmin plays an important role in adult hippocampal neurogenesis and spinogenesis. In addition, stathmin mutation led to impaired NMDA receptor-dependent and neurogenesis-associated memory and did not affect NMDA receptor-independent memory. Moreover, biochemical analysis suggested that stathmin regulates the synaptic transport of NMDA receptors, which in turn influence CREB-mediated gene transcription machinery. Overall, these data suggest that stathmin is an important molecule for neurogenesis, spinogenesis, and NMDA receptor-dependent learning and memory.

Hippocampal MicroRNA-124 Enhances Chronic Stress Resilience in Mice.

UNLABELLED: Chronic stress-induced aberrant gene expression in the brain and subsequent dysfunctional neuronal plasticity have been implicated in the etiology and pathophysiology of mood disorders. In this study, we examined whether altered expression of small, regulatory, noncoding microRNAs (miRNAs) contributes to the depression-like behaviors and aberrant neuronal plasticity associated with chronic stress. Mice exposed to chronic ultra-mild stress (CUMS) exhibited increased depression-like behaviors and reduced hippocampal expression of the brain-enriched miRNA-124 (miR-124). Aberrant behaviors and dysregulated miR-124 expression were blocked by chronic treatment with an antidepressant drug. The depression-like behaviors are likely not conferred directly by miR-124 downregulation because neither viral-mediated hippocampal overexpression nor intrahippocampal infusion of an miR-124 inhibitor affected depression-like behaviors in nonstressed mice. However, viral-mediated miR-124 overexpression in hippocampal neurons conferred behavioral resilience to CUMS, whereas inhibition of miR-124 led to greater behavioral susceptibility to a milder stress paradigm. Moreover, we identified histone deacetylase 4 (HDAC4), HDAC5, and glycogen synthase kinase 3ß (GSK3ß) as targets for miR-124 and found that intrahippocampal infusion of a selective HDAC4/5 inhibitor or GSK3 inhibitor had antidepressant-like actions on behavior. We propose that miR-124-mediated posttranscriptional controls of HDAC4/5 and GSK3ß expressions in the hippocampus have pivotal roles in susceptibility/resilience to chronic stress. SIGNIFICANCE STATEMENT: Depressive disorders are a major public health concern worldwide. Although a clear understanding of the etiology of depression is still lacking, chronic stress-elicited aberrant neuronal plasticity has been implicated in the pathophysiology of depression. We show that the hippocampal expression of microRNA-124 (miR-124), an endogenous small, noncoding RNA that represses gene expression posttranscriptionally, controls resilience/susceptibility to chronic stress-induced depression-like behaviors. These effects on depression-like behaviors may be mediated through regulation of the mRNA or protein expression levels of histone deacetylases HDAC4/5 and glycogen synthase kinase 3ß, all highly conserved miR-124 targets. Moreover, miR-124 contributes to stress-induced dendritic hypotrophy and reduced spine density of dentate gyrus granule neurons. Modulation of hippocampal miR-124 pathways may have potential antidepressant effects.

Imipramine ameliorates pain-related negative emotion via induction of brain-derived neurotrophic factor.

Depression-like behavior is often complicated by chronic pain. Antidepressants including imipramine (IMI) are widely used to treat chronic pain, but the mechanisms are not fully understood. Brain-derived neurotrophic factor (BDNF) is a neuromodulator that reduces depression by regulating synaptic transmission. We aimed to characterize the antidepressant effects of IMI without analgesia based on BDNF (trkB)-mediated signaling and gene expression in chronic pain. A chronic constriction injury (CCI) model was constructed in Sprague-Dawley (SD) rats. IMI (5 mg/kg, i.p.) was administered from day 10 after CCI. The pain response was assessed using the paw withdrawal latency (PWL) and depression was judged from the immobility time in a forced swim test. Anti-BDNF antibody, K252a, or 5,7-dihydroxytryptamine (5,7-DHT) were used to examine the antidepressant effects of imipramine. Changes in pERK1/2 (immunohistochemistry), 5-HT and BDNF (ELISA), and BDNF mRNA (RT-PCR) were measured in the anterior cingulate cortex (ACC), rostral ventromedial medulla (RVM), and spinal cord. After CCI, rats showed decreased PWL and increased immobility time. A low dose of IMI reduced the immobility time without having analgesic effects. This antidepressant effect was reversed by anti-BDNF antibody, K252a, and 5,7-DHT. IMI reduced excessive activation of pERK1/2 associated with decreased pCREB and BDNF mRNA, and these changes were reversed by 5,7-DHT. These results show that IMI reduces pain-related negative emotion without influencing pain and that this effect is diminished by denervation of 5-HT neurons and by anti-BDNF treatment. IMI also normalizes derangement of ERK/CREB coupling, which leads to induction of BDNF. This suggests a possible interaction between 5-HT and BDNF.

Impaired hippocampal spinogenesis and neurogenesis and altered affective behavior in mice lacking heat shock factor 1.

Aberrant transcriptional regulation in the brain is thought to be one of the key components of the pathogenesis and pathophysiology of neuropsychiatric disorders. Heat shock factors (HSFs) modulate cellular homeostasis through the control of gene expression. However, the roles of HSFs in brain function have yet to be elucidated fully. In the present study, we attempted to clarify the role of HSF1-mediated gene regulation in neuronal and behavioral development using HSF1-deficient (HSF1(-/-)) mice. We found granule neurons of aberrant morphology and impaired neurogenesis in the dentate gyrus of HSF1(-/-) mice. In addition, HSF1(-/-) mice showed aberrant affective behavior, including reduced anxiety and sociability but increased depression-like behavior and aggression. Furthermore, HSF1 deficiency enhanced behavioral vulnerability to repeated exposure to restraint stress. Importantly, rescuing the HSF1 deficiency in the neonatal but not the adult hippocampus reversed the aberrant anxiety and depression-like behaviors. These results indicate a crucial role for hippocampal HSF1 in neuronal and behavioral development. Analysis of the molecular mechanisms revealed that HSF1 directly modulates the expression of polysialyltransferase genes, which then modulate polysialic acid-neural cell adhesion molecule (PSA-NCAM) levels in the hippocampus. Enzymatic removal of PSA from the neonatal hippocampus resulted in aberrant behavior during adulthood, similar to that observed in HSF1(-/-) mice. Thus, these results suggest that one role of HSF1 is to control hippocampal PSA-NCAM levels through the transcriptional regulation of polysialyltransferases, a process that might be involved in neuronal and behavioral development in mice.

Manifold alteration between major depressive disorder and healthy control subjects using dynamic mode decomposition in resting-state fMRI data.

Background: The World Health Organization has reported that approximately 300 million individuals suffer from the mood disorder known as MDD. Non-invasive measurement techniques have been utilized to reveal the mechanism of MDD, with rsfMRI being the predominant method. The previous functional connectivity and energy landscape studies have shown the difference in the coactivation patterns between MDD and HCs. However, these studies did not consider oscillatory temporal dynamics. Methods: In this study, the dynamic mode decomposition, a method to compute a set of coherent spatial patterns associated with the oscillation frequency and temporal decay rate, was employed to investigate the alteration of the occurrence of dynamic modes between MDD and HCs. Specifically, The BOLD signals of each subject were transformed into dynamic modes representing coherent spatial patterns and discrete-time eigenvalues to capture temporal variations using dynamic mode decomposition. All the dynamic modes were disentangled into a two-dimensional manifold using t-SNE. Density estimation and density ratio estimation were applied to the two-dimensional manifolds after the two-dimensional manifold was split based on HCs and MDD. Results: The dynamic modes that uniquely emerged in the MDD were not observed. Instead, we have found some dynamic modes that have shown increased or reduced occurrence in MDD compared with HCs. The reduced dynamic modes were associated with the visual and saliency networks while the increased dynamic modes were associated with the default mode and sensory-motor networks. Conclusion: To the best of our knowledge, this study showed initial evidence of the alteration of occurrence of the dynamic modes between MDD and HCs. To deepen understanding of how the alteration of the dynamic modes emerges from the structure, it is vital to investigate the relationship between the dynamic modes, cortical thickness, and surface areas.

Antidepressant Response and Stress Resilience Are Promoted by CART Peptides in GABAergic Neurons of the Anterior Cingulate Cortex.

Background: A key challenge in the understanding and treatment of depression is identifying cell types and molecular mechanisms that mediate behavioral responses to antidepressant drugs. Because treatment responses in clinical depression are heterogeneous, it is crucial to examine treatment responders and nonresponders in preclinical studies. Methods: We used the large variance in behavioral responses to long-term treatment with multiple classes of antidepressant drugs in different inbred mouse strains and classified the mice into responders and nonresponders based on their response in the forced swim test. Medial prefrontal cortex tissues were subjected to RNA sequencing to identify molecules that are consistently associated across antidepressant responders. We developed and used virus-mediated gene transfer to induce the gene of interest in specific cell types and performed forced swim, sucrose preference, social interaction, and open field tests to investigate antidepressant-like and anxiety-like behaviors. Results: Cartpt expression was consistently upregulated in responders to four types of antidepressants but not in nonresponders in different mice strains. Responder mice given a single dose of ketamine, a fast-acting non-monoamine-based antidepressant, exhibited high CART peptide expression. CART peptide overexpression in the GABAergic (gamma-aminobutyric acidergic) neurons of the anterior cingulate cortex led to antidepressant-like behavior and drove chronic stress resiliency independently of mouse genetic background. Conclusions: These data demonstrate that activation of CART peptide signaling in GABAergic neurons of the anterior cingulate cortex is a common molecular mechanism across antidepressant responders and that this pathway also drives stress resilience.

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

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 HERC5, IFI6, and IFI44 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.

Development of an individual fitness score (IFS) based on the depression treatment guidelines of in the Japanese Society of Mood Disorders.

AIM: Treatment guidelines are designed to assist patients and health care providers and are used as tools for making treatment decisions in clinical situations. The treatment guidelines of the Japanese Society of Mood Disorders establish treatment recommendations for each severity of depression. The individual fitness score (IFS) was developed as a simple and objective indicator to assess whether individual patients are practicing treatment by the recommendations of the depression treatment guidelines of the Japanese Society of Mood Disorders. METHODS: The EGUIDE project members determined the IFS through the modified Delphi method. In this article, the IFS was calculated based on the treatment of depressed patients treated and discharged between 2016 and 2020 at facilities participating in the EGUIDE project. In addition, we compared scores at admission and discharge. RESULTS: The study included 428 depressed patients (mild n = 22, moderate/severe n = 331, psychotic n = 75) at 57 facilities. The mean IFS scores by severity were statistically significantly higher at discharge than at admission with moderate/severe depression (mild 36.1 ± 34.2 vs. 41.6 ± 36.9, p = 0.49; moderate/severe 50.2 ± 33.6 vs. 55.7 ± 32.6, p = 2.1 × 10-3; psychotic 47.4 ± 32.9 versus 52.9 ± 36.0, p = 0.23). CONCLUSION: We developed the IFS based on the depression treatment guideline, which enables us to objectively determine how close the treatment is to the guideline at the time of evaluation in individual cases. Therefore, the IFS may influence guideline-oriented treatment behavior and lead to the equalization of depression treatment in Japan, including pharmacotherapy.

[Epigenetic regulation in depression].

Recent research has raised the notion that epigenetic mechanisms (e.g., DNA methylation and histone modifications), which exert lasting control over gene expression without altering the genetic code, could mediate stable changes in brain function. However, the role of environmental factors along with genetic factors in the epigenetic regulation of the pathogenesis of depression is largely unknown. Two genetically distinct mice strains, BALB/c (BALB) and C57BL/6 (B6), exhibit different behavioral responses to chronic stress. With chronic stress, BALB mice showed depressive-like behaviors, but not B6 mice, and glial cell-derived neurotrophic factor (GDNF) expression level was decreased in the ventral striatum of BALB mice but increased in B6 mice. In BALB mice, depressive-like behaviors and decreased GDNF expression were recovered by chronic antidepressant treatment. Therefore, we used these two mice strains to investigate how the epigenetic status of the GDNF gene in the ventral striatum modulates stress vulnerability. Both mice strains showed increased DNA methylation levels and MeCP2 recruitment in the GDNF promoter region. However, histone H3 acetylation level was decreased in BALB mice, but increased in B6 mice. Furthermore, BALB mice showed increased histone deacetylase2 (HDAC2) expression level and Re-ChIP assay revealed HDAC2-MeCP2 complex in BALB mice. Our results indicate the crucial role of histone modification by HDAC2 and MeCP2 complex for the control of GDNF expression and subsequent behavioral responses to chronic stress, in other words, the susceptibility to stress. In addition, we investigated the effect of antidepressants on the epigenetic regulation of GDNF expression. We found a reduced level of HDAC4 recruitment at the GDNF promoter region with antidepressants. Thus, our data suggest that antidepressants increase transcriptional activity of the GDNF gene through the modulation of histone acetylation by HDAC4. Finally, we examined the expressions of GDNF and epigenetic-related molecules mRNAs with major depressive and bipolar disorder patients by using quantitative real-time PCR. We found the aberrant expression of GDNF and epigenetic-related genes including HDAC2 and HDAC4 in mood disorder patients. Thus, our data provide novel insights suggesting that epigenetic mechanisms of GDNF expression are involved in the pathogenesis or pathophysiology of depression.