Biology subjects

Nishiguchi, T.

Publications and source records attributed to Nishiguchi, T..

11 recordsLinked to original sources

bioRxiv2026

Zuranolone mitigates delirium-like bispectral EEG changes, behavioral deficits, and neuroinflammation across surgical and inflammatory mouse models and age groups

Delirium is an acute, fluctuating brain dysfunction that commonly follows surgery and systemic inflammation, disproportionately affects older adults, and remains difficult to quantify continuously over time and treat pharmacologically. Here, we tested whether the neuroactive steroid zuranolone, a positive allosteric modulator of synaptic and extrasynaptic GABA_A receptors, mitigates delirium-like abnormalities across two complementary murine delirium models, a lipopolysaccharide-induced systemic inflammation (LPS) model and a postoperative delirium (POD) model, primarily in young and aged mice, with selected analyses in super-aged mice. Using continuous EEG with a validated bispectral EEG (BSEEG) metric, we found that zuranolone attenuated delirium-like EEG slowing in the LPS model in young mice in a dose-dependent manner and retained efficacy in aged mice. In the POD model, prophylactic dosing provided limited benefit in young mice, whereas post-surgery treatment reduced postoperative BSEEG elevations. In aged mice, prophylactic dosing suppressed POD-associated BSEEG abnormalities, and in super-aged mice, prophylactic zuranolone improved survival after POD induction. In parallel, zuranolone reduced microglial density and activation markers (IBA1 and CD68 immunoreactivity) at 24 h after POD surgery and after LPS challenge, with effects that were particularly evident in peri-screw site tissue in young POD mice and more broadly distributed across regions in aged mice. Finally, in young mice, zuranolone improved a composite behavioral severity score in the LPS model, whereas behavioral effects in the POD model were modest and domain-specific. Together, these findings support zuranolone as a candidate strategy to reduce delirium-like electrophysiological and neuroimmune abnormalities, with the strongest effects in inflammation-driven and age-vulnerable contexts.

neuroscience↗

bioRxiv2025

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↗

bioRxiv2025

Epigenetic markers of middle-age: non-linear DNA methylation changes with aging in humans

BackgroundHuman DNA is known to exhibit an overall tendency toward demethylation with aging. However, assuming a simple linear relationship between DNA methylation and age does not align with the phenotype of human development and the aging process. This study aimed to investigate the existence of DNA methylation patterns with peaks or troughs at specific ages in addition to simple linear changes. MethodsA large-scale dataset of genome-wide DNA methylation data from 10,420 individuals was analyzed. Hierarchical multiple regression models were applied to detect patterns of the association between age and DNA methylation: linear increase, linear decrease, U-shaped curve, and inverse U-shaped curve. ResultsAmong the 864,627 CpG sites analyzed, 8.4% exhibited an increase in DNA methylation with age, 23.9% showed a decrease, and 5.5% were better explained by a quadratic model (P < 5.7815x10 ). Within the non-linear subset, inverse U-shaped CpG sites peaking in methylation during middle age were predominant. Genes exhibiting quadratic association patterns between DNA methylation and age, and those linked to diseases with common onset during middle age, were also detected. ConclusionsNon-linear age-related DNA methylation patterns, with peaks or troughs occurring at specific ages, were detected. This suggests that humans do not simply age linearly, but that programmed mechanisms or cascade-like processes may exist to promote or suppress the expression of specific genes at certain ages, contributing onset of certain diseases at specific timings.

genomics↗

bioRxiv2025

Non-linear Age-related Change in Human Interleukin-11 and the receptor subunit alpha DNA Methylation

IntroductionInterleukin-11 (IL-11) is a cytokine involved in inflammatory processes and a previous study showed that blocking or knocking down IL11 in mice prolongs a healthy lifespan. This study investigates DNA methylation (DNAm) changes in the IL11 and IL-11 receptor subunit alpha (IL-11RA) gene across ages to reveal how aging might influence IL-11 production and sensitivity. MethodsA genome-wide DNAm database focusing on Cytosine-phosphate-Guanine (CpG) sites within the IL11 and IL11RA was analyzed. Hierarchical regression analyses examined the relationship between DNAm, age, and the squared age term for quadratic associations. ResultsThe database comprised 10,297 samples (5,156 males and 5,141 females) with a mean age of 53.9 years (SD = 14.1 years). The majority of IL11 and IL11RA CpG sites in the TSS1500 and 3UTR regions exhibited significant inverse U-shaped associations with age. DNAm levels were low during youth, increased in middle age (40s-50s), and decreased again in older age. ConclusionThe observed inverse U-shaped DNAm patterns in the IL11 and IL11RA suggest n non-linear, age-related regulation of IL-11 expression and sensitivity. These findings indicate that IL-11 may have different roles across life stages and suggest that therapeutic interventions targeting IL-11 should consider age-specific effects.

genetics↗

bioRxiv2025

Glial Contribution to the Pathogenesis of Post-Operative Delirium Revealed by Multi-omic Analysis of Brain Tissue from Neurosurgery Patients

Post-operative delirium (POD) is a common complication after surgery especially in elderly patients, characterized by acute disturbances in consciousness and cognition, which negatively impacts long-term outcomes. Effective treatments remain elusive due to the unclear pathophysiology of POD. To address the knowledge gap, we investigated DNA methylation profiles and gene expression changes in brain cells from POD and non-POD patients who underwent brain resection surgery for medication refractory epilepsy. DNA methylation analysis revealed alteration in epigenetic status of immune and inflammation-related genes. Single-nucleus RNA sequencing (snRNAseq) identified POD-specific glial cell alterations, particularly in microglia, where neuroinflammation was strongly enhanced, consistent with epigenetic findings. Astrocytes exhibited changes in synapse-related functions and migration. Furthermore, downstream analysis indicated similarities between POD-associated glial cell states and pathologies such as encephalitis and dementia. Overall, this study--the first multi-omics analysis of brain tissue from POD patients--provides direct evidence of glial cell contributions to POD pathogenesis, and highlights potential therapeutic targets.

neuroscience↗

bioRxiv2025

The age-related susceptibility to postoperative delirium quantified by bispectral electroencephalography (BSEEG) correlates with postoperative delirium-like behavior in mice

Postoperative delirium (POD) is a severe neuropsychiatric state characterized by acute fluctuating various mental symptoms. Despite its prevalence, the underlying mechanisms of POD remain largely unknown, and effective biomarkers for its detection are lacking. We have successfully developed a novel delirium detection method, the bispectral electroencephalography (BSEEG) method, which has shown excellent performance in delirium detection and outcome prediction. From there, similar to the clinical situation, we hypothesize that BSEEG scores can serve as indicators of POD-like states in mice. This study investigated the correlation between POD-like behavior and BSEEG score in a mouse model following EEG head mount implantation surgery. 2-3 and 22-23 month-old male C57BL/6J mice underwent EEG head-mount implantation surgery, followed by EEG monitoring and a battery of behavioral tests, including Buried Food Test, Open Field Test, and Y-maze, to assess POD-like behavior. We measured BSEEG scores and analyzed the correlation between these scores and the behavior measurements. The results showed that BSEEG scores correlated with attention deficit and decreases in locomotor activity in young mice, whilst BSEEG scores only correlated with a decrease in locomotor activity in aged mice. Notably, composite Z scores representing delirium severity also showed a correlation with BSEEG scores in young mice. Our findings indicate that the BSEEG method can be an indicator of POD-like states consistent with those measured by behavior tests. This study provides a novel preclinical framework for understanding the pathophysiology of POD and underscores the potential of BSEEG as a valuable tool for delirium detection and severity assessment.

animal behavior and cognition↗

bioRxiv2024

LPS-induced delirium-like behavior and microglial activation in mice correlate with bispectral electroencephalography (BSEEG)

Delirium is a multifactorial medical condition characterized by impairment across various mental functions and is one of the greatest risk factors for prolonged hospitalization, morbidity, and mortality. Research focused on delirium has proven to be challenging due to a lack of objective measures for diagnosing patients, and few laboratory models have been validated. Our recent studies report the efficacy of bispectral electroencephalography (BSEEG) in diagnosing delirium in patients and predicting patient outcomes. We applied BSEEG to validate a lipopolysaccharide (LPS)-induced mouse model of delirium. Moreover, we investigated the relationship between BSEEG score, delirium-like behaviors, and microglia activation in hippocampal dentate gyrus and cortex regions in young and aged mice. There was a significant correlation between BSEEG score and impairment of attention in young mice. Additionally, there was a significant correlation between BSEEG score and microglial activation in hippocampal dentate gyrus and cortex regions in young and aged mice. We have successfully validated the BSEEG method by showing its associations with a level of behavioral change and microglial activation in an LPS-induced mouse model of delirium. In addition, the BSEEG method was able to sensitively capture an LPS-induced delirium-like condition that behavioral tests could not capture because of a hypoactive state.

neuroscience↗

bioRxiv2024

The bispectral EEG (BSEEG) method quantifies post-operative delirium-like states in young and aged mice after head mount implantation surgery

Delirium, a syndrome characterized by an acute change in attention, awareness, and cognition, is commonly observed in older adults and has multiple potential triggers, including illness, drug, trauma, and surgery. There are few quantitative monitoring methods in clinical settings. We developed the bispectral electroencephalography (BSEEG) method in clinical research that can detect the presence of and quantify the severity of delirium using a novel algorithm. In the pre-clinical model, we reported that the BSEEG method can capture a delirium-like state in mice following LPS administration. However, its application to post-operative delirium (POD) has not yet been validated in animal experiments. Therefore, this study aimed to create a POD model mouse with the BSEEG method by monitoring BSEEG scores after EEG head-mount implantation surgery throughout the recovery phase. We compared the BSEEG scores of C57BL/6J young (2-3 months old) with aged (18-19 months old) mice for quantitative evaluation of the delirium-like state after the surgery. Postoperatively, both groups showed increased BSEEG scores and a loss of regular diurnal changes in BSEEG scores every daytime and night. In young mice, BSEEG scores and regular diurnal changes recovered relatively quickly to baseline by around postoperative day 3. On the other hand, aged mice had prolonged increases in postoperative BSEEG scores and it reached steady state only after around postoperative day 8. This study suggests the BSEEG method can be utilized to quantitatively evaluate POD and also assess the effect of aging on recovery from POD in pre-clinical model.

neuroscience↗

bioRxiv2024

Persistent tailoring of MSC activation through genetic priming

Mesenchymal stem/stromal cells (MSCs) are an attractive platform for cell therapy due to their safety profile and unique ability to secrete broad arrays of immunomodulatory and regenerative molecules. Yet, MSCs are well known to require preconditioning or priming to boost their therapeutic efficacy. Current priming methods offer limited control over MSC activation, yield transient effects, and often induce expression of pro-inflammatory effectors that can potentiate immunogenicity. Here, we describe a genetic priming method that can both selectively and sustainably boost MSC potency via the controlled expression of the inflammatory-stimulus-responsive transcription factor IRF1 (interferon response factor 1). MSCs engineered to hyper-express IRF1 recapitulate many core responses that are accessed by biochemical priming using the proinflammatory cytokine interferon-{gamma} (IFN{gamma}). This includes the upregulation of anti-inflammatory effector molecules and the potentiation of MSC capacities to suppress T cell activation. However, we show that IRF1-mediated genetic priming is much more persistent than biochemical priming and can circumvent IFN{gamma}-dependent expression of immunogenic MHC class II molecules. Together, the ability to sustainably activate and selectively tailor MSC priming responses creates the possibility of programming MSC activation more comprehensively for therapeutic applications. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=158 SRC="FIGDIR/small/578489v1_ufig1.gif" ALT="Figure 1"> View larger version (49K): org.highwire.dtl.DTLVardef@8be46aorg.highwire.dtl.DTLVardef@40fcdeorg.highwire.dtl.DTLVardef@995a21org.highwire.dtl.DTLVardef@1ec53d0_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2019

Persistent DNA Hyper-methylation Dampens Host Anti-Mycobacterial Immunity

Mycobacterium tuberculosis (Mtb) has co-evolved with humans for millennia and developed multiple mechanisms to evade host immunity. Restoring host immunity in order to shorten existing therapy and improve outcomes will require identifying the full complement by which host immunity is inhibited. Perturbing host DNA methylation is a mechanism induced by chronic infections such as HIV, HPV, LCMV and schistosomiasis to evade host immunity. Here, we evaluated the DNA methylation status of TB patients and their asymptomatic household contacts demonstrating that TB patients have DNA hyper-methylation of the IL-2-STAT5, TNF-NF-{varkappa}B and IFN-{gamma} signaling pathways. By MSRE-qPCR, multiple genes of the IL-12-IFN-{gamma} signaling pathway (IL12B, IL12RB2, TYK2, IFNGR1, JAK1 and JAK2) were hyper-methylated in TB patients. The DNA hyper-methylation of these pathways is associated with decreased immune responsiveness with decreased mitogen induced upregulation of IFN-{gamma}, TNF, IL-6 and IL-1{beta} production. The DNA hyper-methylation of the IL-12-IFN-{gamma} pathway was associated with decreased IFN-{gamma} induced gene expression and decreased IL-12 inducible up-regulation of IFN-{gamma}. This work demonstrates that immune cells from TB patients are characterized by DNA hyper-methylation of genes critical to mycobacterial immunity resulting in decreased mycobacteria-specific and non-specific immune responsiveness.

immunology↗

bioRxiv2018

Schistosomiasis Induces Persistent DNA Methylation and Tuberculosis-specific Immune Changes

Epigenetic mechanisms, like DNA methylation, determine immune cell phenotype. To understand the epigenetic alterations induced by helminth co-infections, we evaluated the longitudinal effect of ascariasis and schistosomiasis infection on CD4+ T cell DNA methylation and the downstream tuberculosis (TB)-specific and BCG-induced immune phenotype. All experiments were performed on human primary immune cells from a longitudinal cohort of recently TB-exposed children. Compared to age-matched uninfected controls, children with active Schistosoma haematobium and Ascaris lumbricoides infection had 751 differentially DNA methylated genes with 72% hyper-methylated. Gene ontology pathway analysis identified inhibition of IFN-{gamma} signaling, cellular proliferation, and the Th1 pathway. Targeted RT-PCR after methyl-specific endonuclease digestion confirmed DNA hyper-methylation of the transcription factors BATF3, ID2, STAT5A, IRF5, PPARg, RUNX2, IRF4 and NFATC1 and cytokines or cytokine receptors IFNGR1, TNFS11, RELT (TNF receptor), IL12RB2 and IL12B (p< 0.001; Sidak-Bonferroni). Functional blockage of the IFN-{gamma} signaling pathway was confirmed with helminth-infected individuals having decreased up-regulation of IFN-{gamma}-inducible genes (Mann-Whitney p < 0.05). Hypo-methylation of the IL-4 pathway and DNA hyper-methylation of the Th1 pathway was confirmed by antigen-specific multidimensional flow cytometry demonstrating decreased TB-specific IFN-{gamma} and TNF and increased IL-4 production by CD4+ T cells (Wilcoxon signed rank P <0.05). In S.haematobium infected individuals, these DNA methylation and immune phenotypic changes persisted at least six months after successful deworming. This work demonstrates that helminth infection induces DNA methylation and immune perturbations that inhibit TB-specific immune control and that the duration of these changes are helminth-specific.

immunology↗