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Matsunaga, H.

Publications and source records attributed to Matsunaga, H..

12 recordsLinked to original sources

Osteopontin Upregulation Defines a Pre-Rupture State in Thoracic Aortic Aneurysms in Mice and Humans

BackgroundThoracic aortic aneurysm (TAA) is a life-threatening condition with an unpredictable lisk of rupture. Current clinical parameters have limited ability to accurately predict imminent rupture. Osteopontin (OPN) has been implicated in aortic aneurysm pathology, however, it role as a marker of imminent rupture remains. unclear. We investigated the dynamics of OPN expression dynamics in a mouse model with predictable rupture timing and validated our findings in human TAA. MethodsOne-month-old fibrillin-1 hypomorphic (Fbn1mgR/mgR) mice were used as a TAA model; with wild-type (WT) mice served as controls. Angiotensin II (AngII) was administered to Fbn1mgR/mgR to induce acute aortic rupture. Single-section transcriptome analysis and immunofluorescence staining were performed on ascending aortic tissue at 24 and 72 hours after AngII infusion, with pre-treatment Fbn1mgR/mgR and WT mice serving as controls. To determine conservation in human disease, we reanalyzed publicly available single-cell RNA sequencing data from ascending thoracic aortic aneurysm (ATAA) patients. ResultsAngII infusion induced progressive mortality beginning at 24 hours, with approximately 60% survival at 72 hours and nearly no survival by 8 days in Fbn1mgR/mgR mice. At this pre-rupture time point, OPN showed prominent upregulation at both mRNA and protein levels in ascending aortic tissues compared to controls. Immunofluorescence staining revealed increased OPN expression in the aortic wall, particularly in regions exhibiting structural deterioration. Reanalysis of human ATAA single-cell data showed elevated OPN expression compared to controls, with enrichment in immune cell populations, especially macrophages. Within the macrophage compartment, subcluster analysis identified a stress-responsive subpopulation (MC1) that was markedly expanded and almost exclusively composed of ATAA-derived cells, representing the primary source of OPN upregulation. ConclusionsOPN upregulation represents a conserved molecular signature of the pre-rupture state in TAA across mice and humans. Our mode, which enables predictable rupture timing, allowed the capture of acute pre-rupture molecular changes, suggesting OPN as a potential biomarker for predicting imminent aortic rupture.

molecular biology↗

Integrating spatial and single-cell multi-omics analysis of induced pluripotent stem cell-derived cervical adenocarcinoma model

Human papillomavirus 18 (HPV18) preferentially infects cervical stem cell-like cells and is strongly associated with adenocarcinoma. However, the mechanisms underlying differentiation into cervical adenocarcinoma remain unclear due to the lack of appropriate experimental models. We aimed to establish a model of HPV18-associated cervical adenocarcinoma and elucidate its molecular and cellular differentiation mechanisms. HPV18 E6/E7 were introduced into induced pluripotent stem cell-derived reserve cell-like cells (iRCs) to generate tumor models. Spatial transcriptomics and single-cell multi-omics analyses were performed to integrate histological and molecular data. A distinct component (Gland_A) exhibited morphological and immunohistochemical features of cervical adenocarcinoma and was efficiently induced in iRC-18 tumors. Gland_A showed increased chromatin accessibility and elevated expression of FOXA1, FOXA2, and ALDH1A1. Analysis of clinical samples confirmed enrichment of ALDH1A1 in HPV-associated adenocarcinomas. This model recapitulates key features of HPV18-associated cervical adenocarcinoma and provides insights into its differentiation mechanisms.

cancer biology↗

Linking Pain and Delirium via Microglial Activation: A Mouse Study Using BSEEG, Behavioral Assays, Immunohistochemistry, and RNA Sequencing

BackgroundThe rising incidence of delirium in surgical and critical care settings, especially in older patients, calls for improved preventative and management strategies. Chronic pain is increasingly recognized as a key risk factor for delirium, and microglial activation may be the central mediator linking these two conditions. MethodsWe used a spared nerve injury (SNI) model of persistent neuropathic pain in tandem with a postoperative delirium (POD) mouse model. Pain assessments, electroencephalography (EEG) recording, and immunofluorescence were performed to characterize pain and delirium-like states. Microglia were isolated for RNA-seq to elucidate gene expression changes comprehensively. ResultsSNI mice showed persistent mechanical hypersensitivity from Day 7 onwards and demonstrated disrupted sleep-wake patterns in EEG indices. Immunofluorescence revealed sustained microglial activation in both the hippocampus and cortex following SNI. RNA-seq analyses indicated the upregulation of pro-inflammatory pathways (e.g., interleukin-6 production, NF-{kappa}B signaling) in SNI mice that also underwent head-mount surgery. Notably, the coincidence of persistent pain and an acute delirium-like state further exacerbated neuroinflammation. ConclusionOur findings suggest that neuropathic pain-induced microglial activation primes the brain for exaggerated inflammatory responses under additional surgical stress, potentially worsening delirium. Further investigations into microglia-focused therapies may inform novel strategies for mitigating delirium in patients with neuropathic pain.

neuroscience↗

Human mutations in SLITRK3 implicated in GABAergic synapse development in mice

We report on biallelic homozygous and monoallelic de-novo variants in SLITRK3 in 3 unrelated families presenting with epileptic encephalopathy associated with a broad neurological involvement characterized by microcephaly, intellectual disability, seizures, and global developmental delay. SLITRK3 encodes for a transmembrane protein that is involved in controlling neurite outgrowth and inhibitory synapse development and that has an important role in brain function and neurological diseases. Using primary cultures of hippocampal neurons carrying patients SLITRK3 variants and in combination with electrophysiology, we demonstrate that recessive variants are loss-of-function alleles. By analyzing the development and phenotype of SLITRK3 KO (SLITRK3-/-) mice, we bring additional evidence of enhanced susceptibility to pentylenetetrazole-induced seizure with the appearance of spontaneous epileptiform EEG, as well as developmental deficits such as higher motor activities and reduced parvalbumin interneurons. Taken together, our results exhibit impaired development of peripheral and central nervous system and support a conserved role of this transmembrane protein in neurological function. Our study delineates an emerging spectrum of human core synaptopathies caused by variants in genes that encode SLITRK proteins and essential regulatory components of the synaptic machinery. The hallmark of these disorders is impaired postsynaptic neurotransmission at nerve terminals; an impaired neurotransmission resulting in a wide array of (often overlapping) clinical features, including neurodevelopmental impairment, weakness, seizures, and abnormal movements. The genetic synaptopathy caused by SLITRK3 mutations highlights the key roles of this gene in human brain development and function.

genetics↗

Reproducible and sensitive micro-tissue RNA-sequencing from formalin-fixed paraffin-embedded tissue for spatial gene expression analysis

Spatial transcriptome analysis of formalin-fixed paraffin-embedded (FFPE) tissues using RNA-sequencing (RNA-seq) provides interactive information on morphology and gene expression, which is useful for clinical applications. However, despite the advantages of long-term storage at room temperature, FFPE tissues may be severely damaged by methylene crosslinking and provide less gene information than fresh-frozen tissues. In this study, we proposed a sensitive FFPE micro-tissue RNA-seq method that combines the punching of tissue sections (diameter: 100 m) and the direct construction of RNA-seq libraries. We evaluated a method using mouse liver tissues at 2 years after fixation and embedding and detected approximately 7,000 genes in micro-punched tissue-spots (thickness: 10 m), similar to that detected with purified total RNA (2.5 ng) equivalent to the several dozen cells in the spot. We applied this method to clinical FFPE specimens of lung cancer that had been fixed and embedded 6 years prior, and found that it was possible to determine characteristic gene expression in the microenvironment containing tumor and non-tumor cells of different morphologies. This result indicates that spatial gene expression analysis of the tumor microenvironment is feasible using FFPE tissue sections stored for extensive periods in medical facilities.

molecular biology↗

Spatial transcriptomics reveals the two cancer stem cell-like populations in triple-negative breast cancer

Gene expression analysis at the single-cell level by next generation sequencing has revealed the existence of clonal dissemination and microheterogeneity in cancer metastasis. The current spatial analysis technologies can elucidate the heterogeneity of cell-cell interactions in situ. To reveal the regional and expressional heterogeneity in primary tumors and metastases, we performed transcriptomic analysis of microtissues dissected from a triple-negative breast cancer (TNBC) cell line MDA-MB-231 xenograft model with our automated tissue microdissection punching technology. This multiple-microtissue transcriptome analysis revealed three cancer cell-type clusters in the primary tumor and axillary lymph node metastasis, two of which were cancer stem cell (CSC)-like clusters (CD44/MYC-high, HMGA1-high). Reanalysis of public single-cell RNA-seq (scRNA-seq) datasets confirmed that the two CSC-like populations existed both in TNBC xenograft models and TNBC patients. In addition, the gene signature of the HMGA1-high CSC-like cluster has the potential to serve as a novel biomarker for diagnosis. The diversity of these multiple CSC-like populations may cause differential anticancer drug resistance, increasing the difficulty of curing this cancer.

cancer biology↗

Deep learning-based chest X-ray age serves as a novel biomarker for cardiovascular aging

Chest X-ray (CXR) is one of the most commonly performed medical imaging tests. Although aging, sex and disease status have been known to cause changes in CXR findings, the extent of these effects has not been fully characterized. Here, we present a deep neural network (DNN) model trained using more than 100,000 CXRs to estimate the patients age and sex solely from CXRs. Our DNN exhibited high performance in terms of estimating age and sex, with Pearsons correlation coefficient between the actual and estimated age of above 0.9 and an area under the ROC curve of 0.98 for sex estimation. The difference between the actual and estimated age is large in CXRs with abnormal findings, suggesting that the estimated age ("CXR age") can be a biomarker for disease status. Furthermore, by applying our DNN to CXRs of consecutive 1,562 hospitalized heart failure patients, we demonstrated that an elevated CXR age is not only associated with aging-related diseases, such as hypertension and atrial fibrillation, but also a worse outcome of heart failure. Given these results, our new concept "CXR age" serves as a novel biomarker for cardiovascular aging and can help clinicians to predict, prevent, and manage cardiovascular diseases.

bioinformatics↗

Exploring Efficient Linear Mixed Models to Detect Quantitative Trait Locus-by-environment Interactions

Genotype-by-environment interactions (GxE) are important for understanding genotype-phenotype relationships. To date, various statistical models have been proposed to account for GxE effects, especially in genomic selection (GS) studies. Generally, GS does not focus on the detection of each quantitative trait locus (QTL), while the genome-wide association study (GWAS) was designed for QTL detection. GxE modeling methods in GS can be included as covariates in GWAS using unified linear mixed models (LMMs). However, the efficacy of GxE modeling methods in GS studies has not been evaluated for GWAS. In this study, we performed a comprehensive comparison of LMMs that integrate the GxE modeling methods to detect both QTL and QTL-by-environment interaction (QxE) effects. Model efficacy was evaluated using simulation experiments. For the fixed effect terms representing QxE effects, simultaneous scoring of specific and non-specific environmental effects was recommended because of the higher recall and improved genomic inflation factor value. For random effects, it was necessary to account for both GxE and genotype-by-trial (GxT) effects to control genomic inflation factor value. Thus, the recommended LMM includes fixed QTL effect terms that simultaneously score specific and non-specific environmental effects and random effects accounting for both GxE and GxT. The LMM was applied to real tomato phenotype data obtained from two different cropping seasons. We detected not only QTLs with persistent effects across the cropping seasons but also QTLs with QxE effects. The optimal LMM identified in this study successfully detected more QTLs with QxE effects.

genetics↗

Activation of prodynorphin neurons in the dorsomedial hypothalamus inhibits food intake and promotes positive valence

The regulation of food intake is one of the major research areas in the study of metabolic syndromes such as obesity. Gene targeting studies have clarified the roles of hypothalamic neurons in feeding behaviour. However, our understanding of neural function under physiological conditions is still limited. Immediate early genes, such as activity-regulated cytoskeleton-associated protein (Arc/Arg3.1), are useful markers of neuronal activity. Here, we investigated the role of Arc/Arg3.1 gene-expressing neurons in the hypothalamus after refeeding using the targeted recombination in active populations method. We identified refeeding-responsive prodynorphin/cholecystokinin neurons in the dorsomedial hypothalamus that project to the paraventricular hypothalamic nucleus. Chemogenetic activation of these neurons decreased food intake and promoted positive valence. Our findings provide insight into the role of newly identified hedonic neurons in the process of feeding-induced satiety.

physiology↗

Prostaglandin in the ventromedial hypothalamus regulates peripheral glucose metabolism

The hypothalamus plays a central role in monitoring and regulating systemic glucose metabolism. The brain is enriched with phospholipids containing poly-unsaturated fatty acids, which are biologically active in physiological regulation. Here, we show that intraperitoneal glucose injection induced changes in hypothalamic distribution and amount of phospholipids, especially arachidonic-acid-containing phospholipids, that were then metabolized to produce prostaglandins. Knockdown of cytosolic phospholipase A2 (cPLA2), a key enzyme for generating arachidonic acid from phospholipids, in the hypothalamic ventromedial nucleus (VMH), lowered insulin sensitivity in muscles during regular chow diet (RCD) feeding. Conversely, the down-regulation of glucose metabolism by high fat diet (HFD) feeding was improved by knockdown of cPLA2 in the VMH through changing hepatic insulin sensitivity and hypothalamic inflammation. Our data suggest that cPLA2-mediated hypothalamic phospholipid metabolism is critical for controlling systemic glucose metabolism during RCD, while continuous activation of the same pathway to produce prostaglandins during HFD deteriorates glucose metabolism.

physiology↗

Population-specific and transethnic genome-wide analyses reveal distinct and shared genetic risks of coronary artery disease

To elucidate the genetics of coronary artery disease (CAD) in the Japanese population, we conducted a large-scale genome-wide association study (GWAS) of 168,228 Japanese (25,892 cases and 142,336 controls) with genotype imputation using a newly developed reference panel of Japanese haplotypes including 1,782 CAD cases and 3,148 controls. We detected 9 novel disease-susceptibility loci and Japanese-specific rare variants contributing to disease severity and increased cardiovascular mortality. We then conducted a transethnic meta-analysis and discovered 37 additional novel loci. Using the result of the meta-analysis, we derived a polygenic risk score (PRS) for CAD, which outperformed those derived from either Japanese or European GWAS. The PRS prioritized risk factors among various clinical parameters and segregated individuals with increased risk of long-term cardiovascular mortality. Our data improves clinical characterization of CAD genetics and suggests the utility of transethnic meta-analysis for PRS derivation in non-European populations.

genetics↗

Transethnic meta-analysis of genome-wide association studies identifies three new loci and characterizes population-specific differences for coronary artery disease

BackgroundGenome-wide association studies (GWAS) provided many biological insights into coronary artery disease (CAD), but these studies were mainly performed in Europeans. GWAS in diverse populations have the potential to advance our understanding of CAD.\n\nMethods and ResultsWe conducted two GWAS for CAD in the Japanese population, which included 12,494 cases and 28,879 controls, and 2,808 cases and 7,261 controls, respectively. Then, we performed transethnic meta-analysis using the results of the CARDIoGRAMplusC4D 1000 Genomes meta-analysis with UK Biobank. We identified 3 new loci on chromosome 1q21 (CTSS), 10q26 (WDR11-FGFR2), and 11q22 (RDX-FDX1). Quantitative trait locus analyses suggested the association of CTSS and RDX-FDX1 with atherosclerotic immune cells. Tissue/cell type enrichment analysis showed the involvement of arteries, adrenal glands and fat tissues in the development of CAD. Finally, we performed tissue/cell type enrichment analysis using East Asian-frequent and European-frequent variants according to the risk allele frequencies, and identified significant enrichment of adrenal glands in the East Asian-frequent group while the enrichment of arteries and fat tissues was found in the European-frequent group. These findings indicate biological differences in CAD susceptibility between Japanese and Europeans.\n\nConclusionsWe identified 3 new loci for CAD and highlighted the genetic differences between the Japanese and European populations. Moreover, our transethnic analyses showed both shared and unique genetic architectures between the Japanese and Europeans. While most of the underlying genetic bases for CAD are shared, further analyses in diverse populations will be needed to elucidate variations fully.

genetics↗