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Kunii, Y.

Publications and source records attributed to Kunii, Y..

6 recordsLinked to original sources

Developmental prefrontal myelination shapes inhibitory interneuron function and adult social behavior

Early-life adversity and abnormal myelination are implicated in psychiatric disorders, but how developmental myelination influences adult social cognition remains unclear. Here, we tested whether disrupting developmental myelination in the medial prefrontal cortex (mPFC) impairs adult social behavior. Using complementary genetic strategies in male mice, we suppressed Myelin Regulatory Factor (Myrf)-dependent myelination locally in the juvenile mPFC or broadly in oligodendrocyte-lineage cells. Both approaches selectively impaired adult social novelty preference while sparing sociability, locomotion, and affective behaviors. Focal prefrontal dysmyelination also reduced social dominance. Spatial transcriptomics revealed coupling between myelin-related genes and parvalbumin (PV) interneuron markers in the healthy mPFC, which was disrupted by developmental hypomyelination. Consistent with this transcriptional alteration, PV interneurons showed reduced high-frequency firing despite preserved intrinsic excitability. In the human prefrontal cortex, MBP-PV expression was correlated in controls but not in individuals with schizophrenia. These findings indicate that developmental prefrontal myelination contributes to PV interneuron maturation and suggest that disrupted oligodendrocyte-interneuron coordination may contribute to impaired social recognition.

neuroscience↗

Integrative Transcriptomics Reveals Layer 1 Astrocytes Altered in Schizophrenia

Schizophrenia is one of the most prevalent psychiatric disorders with unclear pathophysiology despite a century-long history of intense research. Schizophrenia affects multiple networks across different brain regions. The anterior cingulate cortex (ACC) is the region that connects the limbic system to cognitive areas such as the prefrontal cortex and represents a pivotal region for the etiology of schizophrenia; however, the molecular pathology, considering its cellular and anatomical complexity, is not well understood. Here, we performed an integrative analysis of spatial and single-nucleus transcriptomics of the postmortem ACC of people with schizophrenia, together with a thorough histological analysis. The data revealed major transcriptomics signatures altered in schizophrenia, pointing at the dysregulation of glial cells, primarily in astrocytes. We further discovered a decrease in the cellular density and abundance of processes of interlaminar astrocytes, a subpopulation of astrocytes specific to primates that localize in the layer 1 and influence the superficial cortical microenvironment across layer 1 and layers 2/3 of the cortex. Our study suggests that aberrant changes in interlaminar astrocytes could explain the cell-to-cell circuit alterations found in schizophrenia and represent novel therapeutic targets to ameliorate schizophrenia-associated dysfunction.

neuroscience↗

A single-cell atlas of transcribed cis-regulatory elements in the human genome

Transcribed cis-regulatory elements (tCREs), such as promoters and enhancers, are fundamental to modulate gene expression and define cell identity. The detailed mapping of tCREs at single-cell resolution is essential for understanding the regulatory mechanisms that govern cellular functions. Prior tCRE catalogs, limited by bulk analysis, have often overlooked cellular heterogeneity. We have constructed a tCRE atlas using single-cell 5-RNA-seq, capturing over 340,000 single-cells from 23 human tissues and annotating more than 175,000 tCREs, substantially enhancing the scope and granularity of existing cis-regulatory element annotations in the human genome. This atlas unveils patterns of gene regulation, revealing connections between broadly expressed promoters and cell type-specific distal tCREs. Assessing trait heritability at single-cell resolution with a novel tCRE module-based approach, we uncovered the nuanced trait-gene regulatory relationships across a continuum of cell populations, offering insights beyond traditional gene-level and bulk-sample analyses. Our study bridges the gap between gene regulation and trait heritability, underscoring the potential of single-cell analysis to elucidate the genetic foundations of complex traits. These insights set the stage for future research to investigate the impact of genetic variations on diseases at the individual level, advancing the understanding of cellular and molecular basis of trait heritability.

genomics↗

Lipid-correlated alterations in the transcriptome are enriched in several specific pathways in the postmortem prefrontal cortex of Japanese patients with schizophrenia

BackgroundSchizophrenia is a chronic relapsing psychiatric disorder that is characterized by many symptoms and has a high heritability. A previous study showed that specific lipid molecules belong to phosphatidylinositol (PI) and phosphatidylserine (PS) was reduced in the postmortem prefrontal cortex of patients with schizophrenia1. However, signaling pathways contributing to the lipid changes remain unknown. Here we performed two types of transcriptome analyses in patients with schizophrenia: an un-biased transcriptome analysis solely based on RNA-seq data and a correlation analysis between levels of gene expression and lipids. Methodology/Principal FindingsRNA-Seq analysis was performed in the postmortem prefrontal cortex from 10 subjects with schizophrenia and 5 controls. Correlation analysis between the transcriptome and lipidome from 9 subjects which are the same samples in the previous lipidomics study1 (Table 1). Extraction of differentially expressed genes (DEGs) and further sequence and functional group analysis revealed changes of gene expression levels in phosphoinositide 3-kinase (PI3K)-Akt signaling and the complement system. In addition, a correlation analysis clarified alterations in several signaling/metabolic pathways including lipid-correlated genes, most of which are not found as DEGs in transcriptome analysis alone. O_TBL View this table: org.highwire.dtl.DTLVardef@80d74eorg.highwire.dtl.DTLVardef@b780b7org.highwire.dtl.DTLVardef@1637f28org.highwire.dtl.DTLVardef@1315439org.highwire.dtl.DTLVardef@190a230_HPS_FORMAT_FIGEXP M_TBL O_FLOATNOTable 1.C_FLOATNO O_TABLECAPTIONCharacteristics of patients from whom postmortem brain samples were obtained. Abbreviations: PMI, postmortem interval, the time that has elapsed since a person has died; DOI, duration of illness, The samples used in correlation analysis are shown by black circles. C_TABLECAPTION C_TBL ConclusionsThis study provided results of the first integrated analysis of the schizophrenia-associated transcriptome and lipidome within the PFC and revealed that lipid-correlated alterations in the transcriptome are enriched in specific pathways including PI3K-Akt signaling.

pathology↗

Angiopathy with impaired glucose logistics observed in schizophrenia-like model mice

Metabolic dysfunction is thought to contribute to the severity of psychiatric disorders; however, it has been unclear whether current high-simple-sugar diets contribute to pathogenesis of these diseases. Here we demonstrate that a high-sucrose diet during adolescence induces psychosis-related behavioral endophenotypes, including hyperactivity, poor working memory, impaired sensory gating, and disrupted interneuron function in mice deficient for glyoxalase-1 (Glo1), an enzyme involved in detoxification of sucrose metabolites. Further, the high-sucrose diet induced microcapillary impairments and reduced brain glucose uptake in brains of Glo1 deficient mice. Aspirin protected against this angiopathy, enhancing brain glucose uptake, and preventing abnormal behavioral phenotypes. Similar vascular damage to our model mice was found in the brains of randomly collected schizophrenia and bipolar disorder patients, suggesting that psychiatric disorders are associated with angiopathy in the brain caused by various environmental stresses, including metabolic stress.

neuroscience↗

Investigation of betaine as a novel psychotherapeutic for schizophrenia

Betaine is known to act against various biological stresses and its levels were reported to be decreased in schizophrenia patients. Using Chdh (a gene for betaine synthesis)-deficient mice and betaine-supplemented inbred mice, we assessed the role of betaine in psychiatric pathophysiology, and its potential as a novel psychotherapeutic, by leveraging metabolomics, behavioral-, transcriptomics and DNA methylation analyses. The Chdh-deficient mice revealed remnants of psychiatric behaviors along with schizophrenia-related molecular perturbations. Betaine supplementation elicited genetic background-dependent improvement in cognitive performance, and suppressed methamphetamine (MAP)-induced behavioral sensitization. Furthermore, betaine rectified the altered antioxidative and proinflammatory responses induced by MAP and in vitro phencyclidine treatments. Notably, betaine levels were decreased in the postmortem brains from schizophrenia, and a coexisting elevated carbonyl stress, a form of oxidative stress, demarcated a subset of schizophrenia with \"betaine deficit-oxidative stress pathology\". We revealed the decrease of betaine levels in glyoxylase 1 (GLO1)-deficient hiPSCs, which shows elevated carbonyl stress, and the efficacy of betaine in alleviating it, thus supporting a causal link between betaine and oxidative stress conditions. Furthermore, a CHDH variant, rs35518479, was identified as a cis-expression quantitative trait locus (QTL) for CHDH expression in postmortem brains from schizophrenia, allowing genotype-based stratification of schizophrenia patients for betaine efficacy. In conclusion, the present study underscores the potential benefit of betaine in a subset of schizophrenia.

neuroscience↗