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Noguchi, S.

Publications and source records attributed to Noguchi, S..

15 recordsLinked to original sources

Luteal-phase resistance training enhances nocturnal heat dissipation and delta power during sleep

Study ObjectivesThis study examined the effects of resistance training on sleep architecture, physiological heat dissipation, and {delta} power in young adult women during the follicular and luteal phases of the menstrual cycle. MethodsNine healthy young women participated in a four-condition crossover protocol comprising (1) follicular phase non-exercise, (2) follicular phase exercise, (3) luteal phase non-exercise, and (4) luteal phase exercise. The exercise condition consisted of 30 minutes of resistance training at 70% of one-repetition maximum performed during the day. During each night, electroencephalography, body temperature, and core body temperature were measured in the home environment. The distal-proximal body temperature gradient (DPG), which is a validated indicator of heat dissipation, was calculated ResultsResistance training enhanced heat dissipation, as reflected by increased DPG values, and increased the proportion of stage N3 sleep during both menstrual cycle phases, with more pronounced effects during the luteal phase. Sleep from bedtime to wake time was divided into four equal segments. Under the luteal phase with exercise, the appearance of stage N3, {delta} power, and the DPG were elevated in the mid-to-late segments of sleep. ConclusionsThese findings suggest that daytime resistance training promotes nocturnal deep sleep and facilitates thermoregulatory heat loss, as indicated by an increased DPG, particularly during the luteal phase when thermoregulation is less stable than the follicular phase. This training may represent a practical intervention to improve sleep quality and physiological recovery in women across different phases of the menstrual cycle. STATEMENT OF SIGNIFICANCEWomen often experience sleep disturbances during the luteal phase of the menstrual cycle, but the physiological mechanisms and effective interventions remain unclear. This study shows that daytime resistance training enhances nighttime heat dissipation and increases slow-wave sleep during this phase. These findings suggest that exercise is a practical approach to alleviate menstrual cycle-related sleep issues. By clarifying how exercise interacts with thermoregulation and sleep across the cycle, this work contributes to understanding female-specific sleep physiology and supports the development of non-pharmacological strategies to improve womens sleep health in women. Future research should examine the long-term effects of daytime resistance training and compare different exercise modalities across diverse populations.

neuroscience↗

Decoding the emergent properties of microbial community functions through sub-community observations and interpretable machine learning

The functions of microbial communities, including substrate conversion and pathogen suppression, arise not as a simple sum of individual species capabilities but through complex interspecies interactions. Understanding how such functions arise from individual species and their interactions remains a major challenge, limiting efforts to rationally understand microbial roles in both natural and engineered ecosystems. Because current holistic (meta-omics) and reductionist (isolation- or single-cell-based) approaches struggle to capture these emergent microbial community functions, this study explores an intermediate strategy: analyzing simple sub-community combinations to enable a bottom-up understanding of community-level functions. To examine the validity of this approach, we used a nine-member synthetic microbial community capable of degrading the environmental pollutant aniline, and systematically generated a dataset of 256 sub-community combinations and their associated functions. Analyses using random forest models revealed that the sub-community combinations of just three to four species enabled the quantitative prediction of functions in larger communities (5-9-member; Pearsons r = 0.78-0.80). Prediction performance remained robust even with limited sub-community data, suggesting applicability to more diverse microbial communities where exhaustive sub-community observation is infeasible. Moreover, interpreting models trained on these simple sub-community combinations enabled the identification of key species and interspecies interactions that strongly influence the overall community function. These findings provide a methodological framework for mechanistically dissecting complex microbial community functions through sub-community-based analysis.

microbiology↗

Establishment of a second-generation transgenic marmoset model of polyglutamine disease recapitulating neurological symptoms and pathology

Neurodegenerative diseases, including polyglutamine diseases, remain a major clinical challenge, partly because of limited animal models that recapitulate human disease. Here, we describe a second-generation transgenic marmoset model of spinocerebellar ataxia 3 (SCA3), a polyglutamine disease, which stably expresses expanded CAG repeats in ATXN3. All five offspring of the founder marmoset harbored the transgene with reduced transgene integration sites and without repeat instability or genetic mosaicism, offering improved construct validity. Three of the five marmosets developed progressive motor impairments that segregated into two distinct phenotypes: early onset with rapid progression and late onset with mild progression, accompanied by corresponding patterns in body weight gain and grip strength. Pathological analysis revealed cerebellar Purkinje cell loss, spinal cord neurodegeneration, and widespread intranuclear inclusions. The severity of motor phenotypes correlated with transgene expression levels in disease-relevant brain regions, including the cerebellum, spinal cord, and striatum. By overcoming the common translational limitations of rodent systems, our second-generation model offers a powerful platform for investigating disease mechanisms and testing potential therapeutic interventions. Our results advance the utility of transgenic marmosets as clinically relevant models of neurodegenerative diseases. Summary StatementSecond-generation transgenic marmoset models of spinocerebellar ataxia 3 replicated the progressive motor deficits and neuropathology of the founder marmoset, providing a powerful platform for studying disease mechanisms and developing therapies.

neuroscience↗

A novel RyR2-selective stabilizer prevents and ameliorates severe arrhythmias in stress-induced ventricular tachycardia

Background and PurposeAberrant activation of the type 2 ryanodine receptor (RyR2) causes lethal arrhythmias, such as catecholaminergic polymorphic ventricular tachycardia (CPVT). Developing drugs that suppress RyR2 hyperactivation may be key to novel arrhythmia treatments. This study evaluated the antiarrhythmic potential of Ryanozole, a recently developed novel RyR2 modulator with high affinity and selectivity, using CPVT mouse models harboring mutant RyR2s. Experimental approachIn vitro effects of Ryanozole were evaluated by ER Ca2+-based assay and [3H]Ryanodine binding assay using RyR2-expressing HEK293 cells. Two lines of mice with different arrhythmia severity, RyR2-R420W and -K4750Q, were employed for in vivo assessments. Intracellular Ca2+ signals were analyzed in isolated cardiomyocytes using Cal520. Antiarrhythmic effects were evaluated by ECG under catecholaminergic challenge in anesthetized mice and during spontaneous arrhythmias in conscious mice. ECG and echocardiographic parameters were evaluated before and after drug administration. Key resultsRyanozole inhibited both wild type and mutant RyR2s with similar IC50 of 15-40 nM. The inhibition was more potent at lower cytosolic Ca2+ concentrations. It suppressed Ca2+ waves and Ca2+ sparks without affecting action potential-evoked Ca2+ transients. Ryanozole effectively prevented adrenaline-induced arrhythmias and rapidly terminated spontaneous arrhythmias during daily activity. Importantly, Ryanozole did not impair cardiac conduction or contractility, unlike conventional antiarrhythmic drugs. Conclusions and implicationsRyanozole strongly suppresses RyR2 under diastolic Ca2+ conditions, thereby preventing the arrhythmogenic trigger of aberrant Ca2+ release. This mechanism likely provides potent antiarrhythmic effects while preserving cardiac function. Ryanozole is a promising therapeutic candidate treating RyR2-mediated arrhythmias, such as CPVT.

pharmacology and toxicology↗

The gut lactic acid bacteria metabolite, 10-oxo-cis-6,trans-11-octadecadienoic acid, suppresses inflammatory bowel disease in mice by modulating the NRF2 pathway and GPCR-signaling

Various gut bacteria, including Lactobacillus plantarum, possess several enzymes that produce hydroxy fatty acids (FAs), oxo FAs, conjugated FAs, and partially saturated FAs from polyunsaturated FAs as secondary metabolites. Among these derivatives, we identified 10-oxo-cis-6,trans-11-octadecadienoic acid ({gamma}KetoC), a {gamma}-linolenic acid (GLA)-derived enon FA, as the most effective immunomodulator, which inhibited the antigen-induced immunoactivation and LPS-induced production of inflammatory cytokines. The treatment with {gamma}KetoC significantly suppressed proliferation of CD4+ T cells, LPS-induced activation of bone marrow-derived dendritic cells (BMDCs), and LPS-induced IL-6 release from peritoneal cells, splenocytes, and CD11c+ cells isolated from the spleen. {gamma}KetoC also inhibited the release of inflammatory cytokines from BMDCs stimulated with poly-I:C, R-848, or CpG. Further in vitro experiments using an agonist of GPR40/120 suggested the involvement of these GPCRs in the effects of {gamma}KetoC on DCs. We also found that {gamma}KetoC stimulated the NRF2 pathway in DCs, and the suppressive effects of {gamma}KetoC and agonist of GPR40/120 on the release of IL-6 and IL-12 were reduced in Nrf2-/- BMDCs. We evaluated the role of NRF2 in the anti-inflammatory effects of {gamma}KetoC in a dextran sodium sulfate-induced colitis model. The oral administration of {gamma}KetoC significantly reduced body weight loss, improved stool scores, and attenuated atrophy of the colon, in wild-type C57BL/6 and Nrf2+/- mice with colitis. In contrast, the pathology of colitis was deteriorated in Nrf2-/- mice even with the administration of {gamma}KetoC. Collectively, the present results demonstrated the involvement of the NRF2 pathway and GPCRs in {gamma}KetoC-mediated anti-inflammatory responses.

immunology↗

Kaempferol suppresses the activation of mast cells by modulating the expression of FcϵRI and SHIP1

In the present study, we evaluated the effects of kaempferol on bone marrow-derived mast cells (BMMCs). Kaempferol treatment significantly and dose-dependently inhibited IgE-induced degranulation, and cytokine production of BMMCs under the condition that cell viability was maintained. Kaempferol downregulated the surface expression levels of Fc{varepsilon}RI on BMMCs, but the mRNA levels of Fc{varepsilon}RI, {beta}, and {gamma}-chains were not changed by kaempferol treatment. Furthermore, the kaempferol-mediated downregulation of surface Fc{varepsilon}RI on BMMCs was still observed in the presence of a protein-synthesis inhibitor. These results suggest that kaempferol reduced the surface Fc{varepsilon}RI on BMMCs, independently of transcription and translation. We also found that kaempferol inhibited both LPS- and IL-33-induced IL-6 production from BMMCs, without affecting the expression levels of their receptors, TLR4 and ST2. Although kaempferol treatment increased the protein amount of NRF2, a master transcription factor of antioxidant stress, in BMMCs, inhibition of NRF2 did not alter the suppressive effect of kaempferol on degranulation. Finally, we observed that kaempferol treatment increased the levels of mRNA and protein of a phosphatase SHIP1 in BMMCs. These results indicate that kaempferol inhibited the IgE-induced activation of BMMCs by downregulating Fc{varepsilon}RI and upregulating SHIP1, and the SHIP1 increase is involved in the suppression of various signaling-mediated stimulations of BMMCs, such as those associated with TLR4 and ST2.

immunology↗

Distinct chaperonopathy in skeletal muscle associated with the dominant variant in DNAJB4

DnaJ homolog, subfamily B, member 4, a member of the heat shock protein 40 chaperones encoded by DNAJB4, is highly expressed in myofibers. We identified a heterozygous c.270 T>A (p.F90L) variant in DNAJB4 in a family with a dominantly inherited distal myopathy, in which affected members have specific features on muscle pathology represented by the presence of cytoplasmic inclusions and the accumulation of desmin, p62, HSP70 and DNAJB4 predominantly in type 1 fibers. Both Dnajb4- F90L knock-in and knockout mice developed muscle weakness and recapitulated the patient muscle pathology in the soleus muscle, where DNAJB4 has the highest expression. These data indicate that the identified variant is causative resulting in defective chaperone function and selective muscle degeneration in specific muscle fibers. This study demonstrates the importance of DNAJB4 in skeletal muscle proteostasis by identifying the associated chaperonopathy.

neuroscience↗

Imaging-based evaluation of pathogenicity by novel DNM2 variants associated with centronuclear myopathy

Centronuclear myopathy (CNM) is characterized clinically by muscle weakness and pathologically by the presence of centralized nuclei and disarrangement of T-tubules in muscle fibers. DNM2 which encodes a large GTPase dynamin 2 have been identified as a causative gene for CNM. Nevertheless, the identification of DNM2 variants may not always lead to the definitive diagnosis as their pathogenicity is often unknown. In this study, by imaging T-tubule-like structures reconstituted in cellulo, we demonstrated that aberrant membrane remodeling by mutant dynamin 2 is tightly associated with gain-of-function features of DNM2 variants. This simple in cellulo assay provided quantitative data required for accurately evaluating pathogenicity of reported and novel DNM2 variants identified from CNM patients in our cohort. Our approaches combining the in cellulo assay with clinical information of the patients enabled to explain the course of a disease progression by pathogenesis of each variant in DNM2-associated CNM.

cell biology↗

Direct uptake mechanism in lysosome required for neuromuscular homeostasis

The degradation of cellular components plays an essential role in homeostasis. However, the known degradation pathways cannot account for the levels of proteolysis in cells. Here, we demonstrate that cytosolic proteins are imported into lysosomes in an ATP-dependent manner for degradation through a direct uptake mechanism distinct from any known pathway. SIDT2, a lysosomal membrane protein previously reported as an RNA transporter, translocates substrate proteins across the lysosomal membrane. Furthermore, we identify a dominant-negative mutation in SIDT2 that causes neuropathy and distal myopathy with rimmed vacuoles, a protein aggregation disease in humans. We generate Sidt2 knockout mice, recapitulating the characteristic features of this disease. Our results reveal a novel degradation pathway and illustrate its crucial role in cellular proteostasis, physiology, and pathophysiology. One Sentence SummaryDiscovery of a novel proteolytic pathway in cells, the dysfunction of which leads to protein aggregation disease in humans.

cell biology↗

A novel saline-soluble, rapidly-metabolized RyR1 inhibitor rescues volatile anesthesia-induced death and environmental heat stroke in a mouse model relevant to malignant hyperthermia

Mutations in the type 1 ryanodine receptor (RyR1), a Ca2+ release channel in skeletal muscle, hyperactivate the channel to cause malignant hyperthermia (MH) and are implicated in severe heat stroke. Dantrolene, the only approved drug for MH, has the disadvantages of having very poor water solubility and long plasma half-life. We show here that a novel RyR1-selective inhibitor, 6,7-(methylenedioxy)-1-octyl-4-quinolone-3-carboxylic acid (Compound 1, Cpd1), effectively prevents and treats MH and heat stroke in several mouse models relevant to MH. Cpd1 reduced resting intracellular Ca2+, inhibited halothane- and isoflurane-induced Ca2+ release, suppressed caffeine-induced contracture in skeletal muscle, reduced sarcolemmal cation influx, and prevented or reversed the fulminant MH crisis induced by isoflurane anesthesia and rescued animals from heat stroke caused by environmental heat stress. Notably, Cpd1 has great advantages of better water solubility and rapid clearance in vivo over dantrolene. Cpd1 has the potential to be a promising new candidate for effective treatment of patients carrying RyR1 mutations.

pharmacology and toxicology↗

Assessment of mapping strategies for determining the 5'-end of mRNAs and long-noncoding RNAs with short read sequences

BackgroundGenome mapping is an essential step in data processing for transcriptome analysis, and many previous studies have evaluated various methods and strategies for mapping RNA-seq data. Cap Analysis of Gene Expression (CAGE) is a sequencing-based protocol particularly designed to capture the 5{square}-ends of transcripts for quantitatively measuring the expression levels of transcription start sites genome-wide. Because CAGE analysis can also predict the activities of promoters and enhancers, this protocol has been an essential tool in studies of transcriptional regulation. Typically, the same mapping software is used to align both RNA-seq data and CAGE reads to a reference genome, but which mapping software and options are most appropriate for mapping the 5{square}-end sequence reads obtained through CAGE has not previously been evaluated systematically. ResultsHere we assessed various strategies for aligning CAGE reads, particularly [~]50-bp sequences, with the human genome by using the HISAT2, LAST, and STAR programs both with and without a reference transcriptome. One of the major inconsistencies among the tested strategies involves alignments to pseudogenes and parent genes: some of the strategies prioritized alignments with pseudogenes even when the read could be aligned with coding genes with fewer mismatches. Another inconsistency concerned the detection of exon-exon junctions. These preferences depended on the program applied and whether a reference transcriptome was included. Overall, the choice of strategy yielded different mapping results for approximately 2% of all promoters. ConclusionsAlthough the various alignment strategies produced very similar results overall, we noted several important and measurable differences. In particular, using the reference transcriptome in STAR yielded alignments with the fewest mismatches. In addition, the inconsistencies among the strategies were especially noticeable regarding alignments to pseudogenes and novel splice junctions. Our results indicate that the choice of alignment strategy is important because it might affect the biological interpretation of the data.

bioinformatics↗

Quality assessment of single-cell RNA sequencing data by coverage skewness analysis

Analysis and interpretation of single-cell RNA-sequencing (scRNA-seq) experiments are compromised by the presence of poor quality cells. For meaningful analyses, such poor quality cells should be excluded to avoid biases and large variation. However, no clear guidelines exist. We introduce SkewC, a novel quality-assessment method to identify poor quality single-cells in scRNA-seq experiments. The method is based on the assessment of gene coverage for each single cell and its skewness as a quality measure. To validate the method, we investigated the impact of poor quality cells on downstream analyses and compared biological differences between typical and poor quality cells. Moreover, we measured the ratio of intergenic expression, suggesting genomic contamination, and foreign organism contamination of single-cell samples. SkewC is tested in 37,993 single-cells generated by 15 scRNA-seq protocols. We envision SkewC as an indispensable QC method to be incorporated into scRNA-seq experiment to preclude the possibility of scRNA-seq data misinterpretation.

genomics↗

RADICL-seq identifies general and cell type-specific principles of genome-wide RNA-chromatin interactions

Mammalian genomes encode tens of thousands of noncoding RNAs. Most noncoding transcripts exhibit nuclear localization and several have been shown to play a role in the regulation of gene expression and chromatin remodelling. To investigate the function of such RNAs, methods to massively map the genomic interacting sites of multiple transcripts have been developed. However, they still present some limitations. Here, we introduce RNA And DNA Interacting Complexes Ligated and sequenced (RADICL-seq), a technology that maps genome-wide RNA-chromatin interactions in intact nuclei. RADICL-seq is a proximity ligation-based methodology that reduces the bias for nascent transcription, while increasing genomic coverage and unique mapping rate efficiency compared to existing methods. RADICL-seq identifies distinct patterns of genome occupancy for different classes of transcripts as well as cell type-specific RNA-chromatin interactions, and emphasizes the role of transcription in the establishment of chromatin structure.

genomics↗

Combinatorial perturbation analysis reveals divergent regulations of mesenchymal genes during epithelial-to-mesenchymal transition

Epithelial-to-mesenchymal transition (EMT), a fundamental transdifferentiation process in development, produces diverse phenotypes in different physiological or pathological conditions. Many genes involved in EMT have been identified to date, but mechanisms contributing to the phenotypic diversity and those governing the coupling between the dynamics of epithelial (E) genes and that of the mesenchymal (M) genes are unclear. In this study, we employed combinatorial perturbations to mammary epithelial cells to induce a series of EMT phenotypes by manipulating two essential EMT-inducing elements, namely TGF-{beta} and ZEB1. By measuring transcriptional changes in more than 700 E- and M-genes, we discovered that the M-genes exhibit a significant diversity in their dependency to these regulatory elements and identified three groups of M-genes that are controlled by different regulatory circuits. Notably, functional differences were detected among the M-gene clusters in motility regulation and in survival of breast cancer patients. We computationally predicted and experimentally confirmed that the reciprocity and reversibility of EMT are jointly regulated by ZEB1. Our integrative analysis reveals the key roles of ZEB1 in coordinating the dynamics of a large number of genes during EMT, and it provides new insights into the mechanisms for the diversity of EMT phenotypes.

systems biology↗

OVOL2 induces mesenchymal-to-epithelial transition in fibroblasts and enhances reprogramming to epithelial lineages

Mesenchymal-to-epithelial transition (MET) is an important step in cell reprogramming from fibroblasts (a cell type frequently used for this purpose) to various epithelial cell types. However, the mechanism underlying MET induction in fibroblasts remains to be understood. The present study aimed to identify the transcription factors (TFs) that efficiently induce MET in dermal fibroblasts. OVOL2 was identified as a potent inducer of key epithelial genes, and OVOL2 cooperatively enhanced MET induced by HNF1A, TP63, and KLF4, which are known reprogramming TFs to epithelial lineages. In TP63/KLF4-induced keratinocyte-like cell-state reprogramming, OVOL2 greatly facilitated the activation of epithelial and keratinocyte-specific genes. This was accompanied by enhanced changes in chromatin accessibility across the genome. Mechanistically, motif enrichment analysis revealed that the target loci of KLF4 and TP63 become accessible upon induction of TFs, whereas the OVOL2 target loci become inaccessible. This indicates that KLF4 and TP63 positively regulate keratinocyte-associated genes whereas OVOL2 suppresses fibroblast-associated genes. The exogenous expression of OVOL2 therefore disrupts fibroblast lineage identity and facilitates fibroblast cell reprogramming into epithelial lineages cooperatively with tissue-specific reprogramming factors. Identification of OVOL2 as a MET inducer and an epithelial reprogramming enhancer in fibroblasts provides new insights into cellular reprogramming improvement for future applications.

cell biology↗