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Transcriptomic insights into the coordinated regulation of signaling, apoptosis, immunity, and metabolism during Sinonovacula constricta larval metamorphosis.

Metamorphosis is a critical ontogenetic transition for marine bivalves, marking the shift from planktonic to benthic lifestyles, where successful transformation dictates survival. The razor clam Sinonovacula constricta is economically important; however, low larval metamorphosis rates remain a major bottleneck in seedling production. To elucidate the mechanisms governing this process, we performed a comparative transcriptome analysis of S. constricta larvae at pre- and post-metamorphosis stages using Illumina sequencing. A total of 3701 differentially expressed genes (DEGs) were identified, including 3254 up-regulated and 447 down-regulated genes. Functional annotation of the respective top 20 significantly up-regulated and down-regulated DEGs indicated their potential pivotal roles in signal transduction (e.g., up-regulated: CAV1, CHRNA2; down-regulated: APP, NOTCH1), cellular proliferation and differentiation (e.g., up-regulated: TUBA, EGF1; down-regulated: KIF23, TTC25), transcriptional and epigenetic regulation (e.g., up-regulated: NFIL3; down-regulated: OVO, HMX1), substance transport (e.g., up-regulated: LRP2, LRP1B; down-regulated: SLC51A, Slc33a1), substance metabolism (e.g., up-regulated: CPK3, CYP26A1; down-regulated: RDMT1, ADAC), immunomodulation (e.g., up-regulated: CPN2, CRISP2), and protein homeostasis (e.g., up-regulated: HSP27, NAS-27). Functional enrichment analysis further revealed that DEGs were significantly enriched in pathways related to signal transduction and developmental regulation (e.g., Ras, TNF), cell death and homeostasis (e.g., apoptosis), immune responses (e.g., Toll-like receptor), energy metabolism (e.g., lipid), cardiovascular related (e.g., Fluid shear stress), cell junction and architecture (e.g., Tight junction), and infectious disease (e.g., measles). These results suggest a synergistic interplay between signaling, apoptosis, immunity, and metabolism during S. constricta metamorphosis. This study advances our understanding of marine bivalve metamorphosis and offers candidate genes for further mechanistic studies.

Animals

Quantitative susceptibility mapping in neurodegenerative diseases: An umbrella review of iron-related biomarkers and mechanisms.

Pathological iron accumulation is a common pathophysiological hallmark across multiple neurodegenerative diseases (NDDs), motivating the need for accurate, non-invasive quantification methods. Quantitative susceptibility mapping (QSM) is an advanced magnetic resonance imaging (MRI) technique that enables in vivo measurement of tissue magnetic susceptibility (χ), providing a sensitive proxy for iron content. This umbrella review systematically evaluates the diagnostic accuracy, clinical correlations, and distinct iron distribution patterns of QSM in major NDDs, such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and atypical Parkinsonism. We included 15 (13/15 were rated Low or Critically Low on AMSTAR 2) systematic reviews and meta-analyses (through July 15, 2026); however, the findings should be interpreted cautiously because of heterogeneity and the low methodological quality. A Corrected Covered Area (CCA) analysis demonstrated only slight overlap of primary studies across the included reviews (CCA = 5.42%). Collectively, the evidence indicates that QSM provides comparable or higher diagnostic sensitivity and reliability than conventional R2* and SWI techniques, particularly for deep gray matter structures. The findings support significant iron overload in the substantia nigra, particularly in the pars compacta, as a robust biomarker for PD that correlates with motor severity and disease duration. Furthermore, regional iron profiling in the basal ganglia is critical for differential diagnosis; specifically, elevated χ in the putamen and globus pallidus effectively distinguishes multiple system atrophy and progressive supranuclear palsy from idiopathic PD. Distinctively, AD and ALS exhibit specific χ alterations in the thalamus, motor cortex, and hippocampus, reflecting divergent iron-related pathophysiological mechanisms, which correlate with cognitive impairment and upper motor neuron signs. Overall, QSM shows diagnostic promise and offers mechanistic insights into iron-related neurodegenerative processes.

Humans

Clinical and psychological characteristics of adolescents at risk of mood disorders compared with adolescents with suicidal behavior.

Suicide is one of the leading causes of death among adolescents, yet little is understood about the biopsychosocial factors related to suicidality. The demographic, clinical, and biological characteristics of adolescents with and without psychiatric histories may help inform mechanistic approaches to treatment of mood disorders and suicidality. The 'characterizing the inflammatory profile and suicidal behavior in adolescents' and 'RAD arm of the Texas Resilience Against Depression' studies aimed to characterize the clinical and biological profiles of youth with suicidal behavior and youth at risk for mood disorders, compared to healthy adolescents (n&#xa0;=&#xa0;75 in each group). Here, we report the descriptive baseline clinical and psychological characteristics of adolescents at risk of mood disorders and those with suicidal behavior. The adolescents with suicidal behavior reported 3.53 lifetime suicidal events on average, predominantly reported moderate to very severe depression (34.7%, 24%, to 9.3%), moderate to severe anxiety (58.6%), low optimism (91.9%), and mild (39.2%) to moderate (28.4%) degree of hopelessness. The at-risk adolescents predominantly reported no depression (60%) or anxiety (68.9%), moderate optimism (50%), and a positive outlook (85.7%). Healthy adolescents predominantly reported no depression (88.3%) or anxiety (93.2%), moderate optimism (59%), and a positive outlook (87%). The adolescents with suicidal behavior and those at risk of mood disorders exhibited significantly higher irritability and borderline personality disorder features (uncorrected p&#xa0;=&#xa0;0.02 to p&#xa0;<&#xa0;0.001) and lower resilience compared to healthy adolescents. Ongoing investigations using the longitudinal clinical and biological data will help identify the immune biosignatures of suicidality in youth.

Humans

A therapeutic atlas of monogenic inflammatory bowel disease.

BACKGROUND AND AIMS: Evidence-based, mechanism-guided therapies are urgently needed for treating monogenic inflammatory bowel disease (mIBD). For such rare diseases, mechanistic insight is essential to guide treatment when conventional clinical trials are often not feasible. We aimed to summarize literature-based evidence and to identify knowledge gaps. METHODS: We conducted a systematic review of published manuscripts evaluating the therapeutic efficacy in mIBD. We quantified and compared the global therapeutic response score across treatments and conditions. In a subset of conditions, biomarkers of longitudinal therapeutic response were evaluated in comparison to non-monogenic pediatric IBD cohorts. RESULTS: Responses to 35 therapeutics across the 102 known genetic causes of mIBD were evaluated in 241 articles and 669 patients, summarizing 302 gene-drug responses. The efficacy of at least one pharmacological intervention was identified in 61% (n&#x2009;=&#x2009;62/102) of the mIBD conditions, highlighting a major unmet need for effective medications in many others. Gene- and pathway-specific responses were demonstrated for several therapies, including allogeneic hematopoietic stem cell transplantation, gene therapy, and advanced therapies such as anti-TNF agents, IL-1 inhibitors, mTOR inhibitors, as well as eculizumab in CD55 deficiency, abatacept in CTLA4 deficiency, and the immunometabolic agent empagliflozin in glycogen storage disease type 1b. CONCLUSIONS: This study highlights the potential of precision medicine approaches tailored to genetic and pathway-specific mechanisms, while underscoring the urgent need for effective therapies in many monogenic conditions that remain without established treatment options.

Humans

New Evidence in Heart Failure: 2026 Update.

Heart failure (HF) remains a major cause of morbidity, mortality, impaired quality of life and healthcare expenditure worldwide. The global burden of HF continues to increase due to population aging, improved survival, and the growing prevalence of cardiovascular, renal, and metabolic comorbidities. Simultaneously, the pace of scientific progress in HF has accelerated considerably. Recent advances have refined our understanding of HF epidemiology, prognosis, and disease trajectories, including emerging concepts of HF improvement, remission, and recovery. The Second Universal Definition of HF has also updated the classification framework, moving beyond the traditional ejection fraction-based categories. HF is now broadly classified into two major phenotypes: heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). Novel mechanistic insights highlight the role of inflammation, immune activation, metabolic dysfunction, mitochondrial biology, and multisystem interactions in HF progression. There has also been significant progress in the characterization and management of major comorbidities, including chronic kidney disease (CKD), diabetes, obesity, atrial fibrillation (AF), pulmonary hypertension, frailty, malnutrition, and cancer. Diagnostic innovations include novel biomarkers, multi-omics technologies, artificial intelligence-based approaches, advanced imaging techniques, congestion assessment tools, and emerging digital health solutions. Important advances have occurred in specific HF aetiologies, including cardiomyopathies, cardiac amyloidosis (CA), myocarditis, arrhythmia-induced cardiomyopathy (AiCM), and Chagas cardiomyopathy. Therapeutic developments continue to reshape HF management across the spectrum of left ventricular ejection fraction. Recent evidence has focused on optimization of guideline-directed medical therapy in HFrEF, expansion of evidence-based therapies in HFpEF, and growing roles for sodium-glucose cotransporter-2 inhibitors, finerenone, incretin-based therapies, and transcatheter valve interventions. Collectively, these advances support the transition from a predominantly phenotype-based approach towards a more personalized and biologically informed model of HF care, with the potential to further improve outcomes across the entire HF spectrum.

Journal Article

Illicium verum polysaccharide targets fimbriae and flagella to disrupt biofilm and inhibit multidrug-resistant Escherichia coli proliferation.

The widespread dissemination of multidrug-resistant (MDR) E. coli has led to a decrease in the efficacy of antibiotics, posing severe challenges to clinical anti-infective therapy. Owing to their safety, multitarget activities, and low risk of inducing drug resistance, plant polysaccharides represent a promising alternative strategy. In this study, an acidic polysaccharide (IVP-3) was isolated and purified from the medicinal and edible plant Illicium verum, and it was found to inhibit MDR E. coli colonization by disrupting its biofilm. The Mw of IVP-3 was determined to be 35.566&#xa0;kDa. Its backbone consists of &#x2192;4)-&#x3b1;-D-GalpA-6-OMe-(1&#x2192;, &#x2192;4)-&#x3b1;-D-GalpA-(1&#x2192;, &#x2192;4)-&#x3b2;-D-Galp-(1&#x2192;, and &#x2192;3,4)-&#x3b1;-D-GalpA-(1&#xa0;&#x2192;&#xa0;residues, whereas the branched chain is composed of &#x3b1;-L-Araf-(1&#xa0;&#x2192;&#xa0;5)-&#x3b1;-L-Araf-(1&#xa0;&#x2192;&#xa0;attached to the O-5 position of &#x2192;2,5)-&#x3b1;-L-Araf-(1&#x2192;, which is further linked to the O-3 position of the backbone. Mechanistically, IVP-3 disrupts the structure of fimbriae and flagella, inhibits bacterial motility, effectively prevents initial biofilm adhesion, and eradicates preformed mature biofilms. Additionally, IVP-3 damages cell membrane integrity, disrupts the proton motive force, and induces energy metabolism disorder, efflux pump inhibition, and oxidative stress, ultimately leading to bacterial lysis. This study provides a theoretical basis for the development of natural antibacterial agents targeting MDR E. coli biofilms and for the high-value utilization of Illicium verum.

Biofilms

Evolutionary conservation of heat shock proteins in Blattodea and their roles in wing morphogenesis and ovarian development of Blattella germanica.

Heat shock proteins (Hsps) are essential molecular chaperones for protein homeostasis and stress responses. However, the Hsp repertoires and functions in Blattodea remain underexplored. Our genome-scale survey of nine Blattodea species revealed 37-46 conserved Hsp90, Hsp70, and DNAJ (Hsp40) genes, with DNAJ the most abundant and Hsp90 the least. Phylogenetic analysis confirmed the evolutionary conservation of three Hsp90, seven Hsp70, and 29 DNAJ subclades in Blattodea. Selection pressure analysis revealed predominant purifying selection (dN/dS&#xa0;&#x226a;&#xa0;1) across lineages, strongest in DNAJ and highest in Hsp90 conservation. In Blattella germanica, expression of six representative BgHsp genes progressively increased during development, peaking in fifth-instar nymphs. Tissue expression profiling revealed that BgHspA1-2/3/4 were predominantly expressed in legs, BgDNAJB5 and BgHsp90AB1-2 were enriched in the fat body, and BgHsp90AB1 was highly expressed in the head. dsRNA injection targeting conserved Hsp gene regions achieved 61.9-94.1% knockdown of all six target genes. RNAi knockdown of six BgHsp genes disrupted wing morphogenesis, causing distinct phenotypes: wing whitening (56.7%, dsBgHspA1-4), unequal length (66.7%, dsBgHspA1-3; 76.7%, dsBgDNAJB5), and wing wrinkling (70%, dsBgHspA1-2; 63.3%, dsBgHsp90AB1; 76.7%, dsBgHsp90AB1-2). During ovarian formation, the developmental delay was most severe in the dsBgHsp90AB1 group, moderate in the dsBgHsp90AB1-2 and dsBgHspA1-2/3/4 groups, and weakest in the dsBgDNAJB5 group. Besides, knockdown significantly downregulated key developmental genes (apterous-a, nubbin, scalloped, ultrabithorax, wingless, and vitellogenin). These findings provide a reference for understanding the evolutionary patterns of Hsps in Blattodea, and offer mechanistic insights into the developmental regulation mediated by Hsps in this important public-health pest.

Animals

Utility of monocyte-derived cells to investigate immune-mediated drug-induced liver injury.

Immune-mediated drug-induced liver injury (DILI) is triggered or exacerbated by the immune system mounting an attack against the drug or its metabolites. The array of in vitro assays for evaluating drug immune liability is limited, highlighting a significant gap in effectively predicting and understanding immune-mediated hepatotoxicity. We aimed to investigate whether monocytes differentiated with the Metaheps (MH) protocol could provide insights into the molecular mechanisms of immune-mediated DILI. MH were generated from monocytes of healthy volunteers (HV) and DILI patients. MH phenotypic characterization was performed by proteomics and qPCR. MH sensitivity to drugs associated with immune-mediated DILI was assessed by lactate dehydrogenase (LDH) assay. Drug-induced LDH release by DILI-derived MH was compared to the upper limit of the 95% CI calculated from HV-derived MH cells treated with the same drug. The 95% CI determined in HV-derived MH was set as the sensitivity threshold for the specific drug. MH cells retain the expression of several immune-related proteins of the parental monocytes and activate a pro-inflammatory response upon exposure to lipopolysaccharide. For all MH (6 out of 6) generated from patients with penicillin-induced DILI, the LDH release upon re-challenge was above the threshold. The sensitivity of MH generated from seven patients with immune checkpoint inhibitor (ICI)-induced hepatotoxicity was ICI-dependent, responding to nivolumab and/or ipilimumab (4 out of 5), but not to pembrolizumab (0 out of 2). Additionally, DILI-derived MH were not sensitive to non-DILI drugs. In conclusion, monocyte-derived cells may serve as an additional tool for drug-specific mechanistic studies of immune-mediated DILI.

Humans

Fatty acids and breast cancer: Epidemiology, subtype-specific metabolism, immune regulation, and clinical translation.

Fatty acids (FAs) are bioactive dietary and metabolic molecules that participate in membrane architecture, energy homeostasis, inflammatory signaling, gene regulation and immune function, all of which intersect with breast cancer (BC) risk, progression and treatment response. In this narrative review we integrate epidemiological, clinical, translational and mechanistic evidence on the role of FAs in BC. Saturated, monounsaturated, trans- and polyunsaturated FAs (PUFAs) are treated as distinct biological exposures rather than interchangeable measures of total fat intake. Similarly, evidence from dietary assessment, circulating biomarkers, erythrocyte membrane composition, adipose tissue stores and tumor lipid signatures is interpreted separately, because each captures exposure and biology at a different level. BC subtypes differ in FA synthesis, uptake, oxidation, storage and remodeling: luminal tumors are frequently linked to hormone-regulated lipogenesis, human epidermal growth factor receptor 2 (HER2)-positive tumors to growth-factor-driven lipid metabolism, and triple-negative tumors to exogenous FA uptake, inflammatory lipid mediators and ferroptosis-related vulnerabilities. FA-derived mediators also shape immune-cell polarization, cytokine signaling and the tumor microenvironment, and dietary FAs may reshape the gut microbiota; the fiber-derived short-chain FAs it produces, distinct from dietary FAs, likewise help regulate immune and inflammatory tone. Clinical data suggest possible roles for fat-quality modification and selected n-3 PUFA interventions, but findings are heterogeneous and not yet sufficient to support routine biomarker-guided precision onco-nutrition. Candidate biomarkers, such as erythrocyte n-6:n-3 composition, require prospective validation before clinical implementation. FA biology thus represents a modifiable but complex axis in BC prevention, tumor biology and supportive care.

Humans

Transcriptomic insights into temperature regulation of proliferation and differentiation in skeletal muscle cells of Nibea albiflora.

Myogenesis involves sequential stages of muscle satellite cell activation, myoblast proliferation, differentiation, and fusion into multinucleated myotubes. Teleost muscle exhibits indeterminate growth and is highly sensitive to environmental temperature, yet the underlying mechanisms by which temperature regulate proliferation and differentiation remain poorly understood. In this study, we established a primary skeletal muscle cell culture from the yellow drum (Nibea albiflora), an economically important marine fish, and integrated morphological observations with comparative transcriptomics analysis to characterize cellular and molecular responses at 28&#xa0;&#xb0;C and 20&#xa0;&#xb0;C during both proliferation and differentiation stages. Phenotypic analysis revealed that 28&#xa0;&#xb0;C significantly enhanced both myoblast proliferation and myogenic differentiation ability compared with 20&#xa0;&#xb0;C. Transcriptomic profiling revealed that at 28&#xa0;&#xb0;C, differentiation upregulated extracellular matrix(ECM) organization, calcium signaling, and sarcomere assembly, while proliferation enhanced focal adhesion, growth factor signaling, and lipid metabolism. At 20&#xa0;&#xb0;C, differentiation was characterized by glutathione metabolism, and ferroptosis, while proliferation involved cytokine-cytokine receptor interaction and negative regulation of signal transduction. Core myogenic regulatory factors (MRFs), particularly myogenin, were strongly upregulated at 28&#xa0;&#xb0;C during the differentiation stage, serving as an internal control. Based on these findings, we propose a testable model that elevated temperature coordinates Ca2+-dependent MRF activation with ECM-integrin signaling to drive sarcomere assembly and muscle growth. Key differentially expressed genes (DEGs) regulating myogenesis in N. albiflora were also identified. This study provides a mechanistic framework for temperature adaptation in teleost skeletal muscle and identifies candidate genes for functional validation and marker-assisted selection, as well as a rationale for temperature management strategies to improve aquaculture yield of N. albiflora.

Animals

Pathogenic properties of myasthenia gravis AChR autoantibodies associate with clinical response to efgartigimod.

BACKGROUND: Efgartigimod, a neonatal Fc receptor (FcRn) blocker, effectively reduces total IgG, including pathogenic acetylcholine receptor (AChR) autoantibodies in myasthenia gravis (MG); however, clinical responses vary. To investigate this variability, we studied how efgartigimod impacts AChR-specific autoantibody profiles and associated pathogenic mechanisms, including complement activation, AChR internalisation and ACh-binding site blockade. METHODS: Serum samples (N=150) were sourced from 50 AChR autoantibody-positive generalised MG patients participating in the phase 3 ADAPT study, randomised to receive efgartigimod (N=40) or placebo (N=10) in cycles of 4-weekly infusions. Samples were collected at baseline, day 29 and day 57 during the first cycle. Live cell-based assays quantified AChR-specific IgG subclasses and isotypes and assessed their capacity to mediate pathomechanisms. RESULTS: Efgartigimod decreased all detectable AChR-specific IgG subclasses. At baseline, AChR autoantibody-mediated C3b deposition, AChR internalisation and ACh-binding site blockade were detected in 42 (84%), 41 (82%) and 10 (20%) patients, respectively. After 4-weekly infusions of efgartigimod, the magnitude of all three pathomechanisms was significantly decreased. However, the extent of this reduction varied across individuals. Double responders on both MG-activities of daily living and quantitative MG scores demonstrated a greater reduction in complement activity and AChR internalisation compared with patients who responded on only one score or were double non-responders. In addition, efgartigimod reduced IgG-dependent IgM binding to AChR. CONCLUSIONS: These findings suggest that clinical efficacy may be more closely associated with functional modulation of the AChR-specific autoantibodies than with their absolute quantity alone. These results support the evaluation of mechanistic pathway monitoring as a potential strategy to predict or guide efgartigimod treatment response.

Humans

Discovery of NAT-6-321056 as a novel modulator of VEGFR2 signaling to suppress tumor angiogenesis.

Vascular endothelial growth factor receptor 2 (VEGFR2) is a master regulator of angiogenesis and cancer progression. However, current VEGFR2 modulators face significant challenges, including off-target toxicity and acquired resistance, underscoring the urgent need for novel therapeutic agents with improved efficacy and safety profiles. Here, we reported that virtual screening of 39,442 natural products from the ZINC natural products-derived library, coupled with molecular docking and molecular dynamics (MD) simulations to evaluate the binding stability of candidate compounds, identified NAT-6-321056 as a highly promising modulator of VEGFR2 signaling. Biological evaluations demonstrated that NAT-6-321056 exerted potent inhibition on the growth of a broad spectrum of cancer cells, including both solid tumors and hematological malignancies. In EA.hy 926 endothelial cells and SK-N-DZ neuroblast cells, the compound significantly suppressed proliferation, migration, and invasion. Microscale thermophoresis (MST) confirmed direct binding of NAT-6-321056 to VEGFR2 with favorable affinity. Kinase profiling against a panel of 33 kinases indicated that NAT-6-321056 exhibited a multi-kinase modulation profile. Mechanistic studies revealed that NAT-6-321056 suppressed the expression of hypoxia-inducible factor 1-alpha (HIF-1&#x3b1;) and was associated with reduced VEGFR2 phosphorylation and attenuation of the downstream ERK/JNK/AKT signaling pathways. Moreover, NAT-6-321056 exhibited robust in vivo anti-angiogenic effects in both the chick chorioallantoic membrane (CAM) assay and transgenic zebrafish vascular fluorescence imaging models. Computational absorption, distribution, metabolism, excretion, and toxicity (ADMET) prediction suggested acceptable drug-like properties. Collectively, these findings demonstrated that NAT-6-321056 is a promising modulator of VEGFR2 signaling with potent anti-angiogenic activity and represents a viable candidate for cancer therapy.

Vascular Endothelial Growth Factor Receptor-2

Acetazolamide to prevent ventilatory drive withdrawal in REM sleep apnoea: a randomised controlled trial.

BACKGROUND: Obstructive sleep apnoea (OSA) pathogenesis during rapid-eye movement (REM) sleep has been linked to dips in ventilatory drive and downstream genioglossus hypotonia. The carbonic anhydrase inhibitor acetazolamide is known to increase ventilatory drive and improve OSA severity. Therefore, we tested the effect of acetazolamide on REM-predominant OSA severity (apnoea hypopnoea index (AHI) and hypoxic burden, co-primary outcomes) and underlying physiological mechanisms (ventilatory drive, ventilation and pharyngeal muscle activity). METHODS: 11 participants with REM-predominant OSA per baseline polysomnography (REM AHI/non-REM AHI&#x2265;2) were allocated to receiving acetazolamide 500&#x2009;mg for three nights (first night at half dose) or placebo according to a randomised, crossover, double-blind design. Detailed physiological polysomnography with recording of diaphragm and genioglossus electromyography was conducted after each intervention, with a 1-week washout in between. RESULTS: As hypothesised, acetazolamide reduced AHI by 35.5% (95% CI 23.1% to 46.3%) and hypoxic burden by 35.9% (95% CI 21.1% to 48.4%) vs placebo (p<0.001), meeting the primary endpoint. Mechanistic analysis in REM revealed that, unexpectedly, acetazolamide did not mitigate dips in ventilatory drive versus placebo (first decile (+0.1 (-1.0 to 1.3) L/min, p=0.8). Rather, acetazolamide reduced collapsibility (increased ventilation at eupneic drive: +1.4 (1.2 to 1.8) L/min) and raised muscle responsiveness (ventilation vs drive slope: +32 (25 to 41) %ventilation/drive, p<0.001; genioglossus versus drive slope: +0.33 (0.13 to 0.54) %max/(L/min), p=0.001). CONCLUSIONS: Acetazolamide modestly improved REM OSA, with meaningful improvements in upper airway physiology, but failed to mitigate the dips in ventilatory drive responsible for REM OSA. TRIAL REGISTRATION NUMBER: NCT05589792.

Humans

Multi-omics reveal microbial functional traits and antifungal metabolites associated with lower Pseudogymnoascus destructans loads in bat cave soils.

White-nose syndrome, caused by Pseudogymnoascus destructans (Pd), is a major fungal disease threatening hibernating bats. Cave soils can serve as environmental reservoirs for Pd, yet the microbial and biochemical mechanisms underlying naturally low Pd burdens in some cave environments remain poorly understood. Here, we integrated soil microbiome profiling, metagenomics, metabolomics, multi-omics network analysis, and in vitro validation to investigate the ecological and functional basis of differential Pd loads in hibernating bat caves in Northeast China. The three caves shared cold, humid, and weakly acidic microenvironments, but differed significantly in electrical conductivity, soil water content, nutrient availability, and extracellular enzyme activities. Soil microbial communities showed significant inter-cave variation in composition, diversity, and niche breadth, with stochastic processes contributing substantially to community assembly. Environmental variables, particularly pH and Pd load, were important predictors of microbial community structure. Functional analyses revealed that the low-Pd Gezi Cave was enriched in genes associated with organic carbon degradation, nitrogen input and retention, and secondary metabolism. Metabolomic profiling further identified cave-specific metabolite signatures, among which Biochanin A, 4-Hydroxybenzaldehyde, Vanillin, and Arachidonic acid were negatively correlated with Pd loads. Integrated pathway and network analyses showed that differential genes and metabolites jointly mapped to secondary metabolite biosynthesis, aminobenzoate degradation, and flavonoid degradation pathways, forming a microbe-metabolite-functional gene coupling network involving key taxa such as Rhodococcus, Pseudorhodoplanes, and Rhodoplanes. In vitro assays confirmed that 4-Hydroxybenzaldehyde, Coumarin, and Vanillin inhibited Pd growth. Structural equation modelling further indicated that environmental heterogeneity was associated with variation in Pd loads through microbial functional attributes and metabolite profiles. These findings suggest that naturally low-Pd cave soils are associated with coordinated environmental filtering, microbial functional specialization, and antifungal metabolite production, providing mechanistic insight into microbial and biochemical constraints on Pd persistence in cave reservoirs.

Animals

Form and function of actin impacts actin health and aging.

The actin cytoskeleton is a fundamental and highly conserved structure that functions in diverse cellular processes, yet its direct contribution to organismal aging remains unclear. Here, we systematically interrogated how genetic and pharmacologic perturbations of actin structure and function influence lifespan and various hallmarks of aging in Caenorhabditis elegans. Whole-animal and tissue-specific knockdown of actin and key actin-binding proteins (ABPs)-arx-2 (Arp2/3), unc-60 (cofilin), and lev-11 (tropomyosin)-led to premature disruption of filament organization, reduced lifespan, and tissue-specific physiological defects. Actin dysfunction also displayed a more "aged" transcriptome using previously validated transcriptomics clocks, and broadly exacerbated many age-associated phenotypes, including mitochondrial dysfunction, lipid dysregulation, loss of proteostasis, impaired autophagy, and intestinal barrier failure. Pharmacological destabilization with Latrunculin A mirrored genetic knockdowns, while mild stabilization with Jasplakinolide modestly extended lifespan, emphasizing that optimal and finely tuned actin function is critical for healthy aging. Finally, analysis of human genome-wide association data revealed that common ACTB polymorphisms correlate with differences in age-related decline in gait speed, suggesting some links between aging and actin across organisms. Taken together, our results provide a comprehensive and publicly accessible resource that maps, for the first time, how changes in actin integrity correlate with diverse aging phenotypes across tissues. This descriptive framework is intended to enable future mechanistic discovery by offering a deep, unbiased dataset that can be integrated with emerging studies to define how actin dynamics can potentially influence aging.

actin

Global prevalence of metabolic syndrome in adults with obstructive sleep apnea: a systematic review and meta-analysis.

STUDY OBJECTIVES: Metabolic syndrome (MetS) is considered to exhibit increased prevalence among adults with obstructive sleep apnea (OSA), but the reported prevalence estimates among such patients vary. Thus, this systematic review and meta-analysis aimed to investigate the global prevalence of MetS in adults with confirmed OSA. MATERIALS AND METHODS: Ovid Medline, Embase, CINAHL, and the Cochrane Library databases were searched for all primary studies published in English that used standard polysomnography for OSA diagnosis and reported MetS estimates. At least two reviewers independently screened for eligible studies, extracted data, and graded the risk of bias using the Risk of Bias Assessment Tool for Non-randomised Studies. Three-level random-effects model was applied for the meta-analysis, reporting pooled prevalence estimate with 95% confidence intervals (CIs). Pre-specified subgroup analyses and meta-regression were also performed. Heterogeneity was quantified using I2 and chi-square statistics. RESULTS: A total of 102 studies were eligible for inclusion (34&#x2009;013 adults with OSA from 28 countries). The combined MetS prevalence was 55.4% (95% CI: 51.0%, 59.8%). Considerable heterogeneity was noted among the included studies (I2&#x2009;=&#x2009;97.8%), whilst the risk of bias ranged from low to high. Subgroup analysis examining the effects of geographic region, study design, MetS definition, and apnea-hypopnea index threshold showed a significant variation in prevalence estimates across most subgroups (p&#x2009;<&#x2009;0.0001). Meta-regression analysis indicated a positive association between mean body mass index (&#x3b2;&#x2009;=&#x2009;0.0772, t&#x2009;=&#x2009;4.56, p&#x2009;<&#x2009;0.0001) and MetS prevalence. CONCLUSIONS: MetS has a high prevalence among adults with polysomnography-confirmed OSA, underscoring the need for prompt MetS screening in these patients. Future longitudinal and genetic/mechanistic studies should investigate the factors accounting for this association. PROSPERO REGISTRATION NUMBER: CRD420251073055.

Humans

Peripheral pain threshold, glycaemic status, and LAMP3 genetic variation: A community-based analysis.

Diabetic polyneuropathy is a common complication of diabetes, yet substantial inter-individual variation in peripheral pain perception suggests underlying genetic influences. This population-based study investigated clinical, metabolic, and genetic determinants of pain threshold using intraepidermal electrical stimulation in 906 participants from the Iwaki Health Promotion Project 2017. Genome-wide association analysis identified 12 loci showing suggestive associations, among which a missense variant in LAMP3 (rs482912) was prioritized as a biologically plausible candidate. Phenotype-stratified analyses showed that individuals carrying the CT or CC genotypes had lower PINT indices than those with the TT genotype, indicating reduced pain thresholds. Notably, the CC genotype retained an association with lower pain threshold using intraepidermal electrical stimulation under conditions of metabolic stress, including impaired glucose tolerance, elevated HbA1c, and obesity, whereas this association was attenuated in the presence of hypertension. Single-cell RNA sequencing analysis of human skin revealed that LAMP3-positive mature dendritic cells, enriched in immunoregulatory molecules, exhibited transcriptional enrichment of inflammatory, antigen-presenting, and nociception-related pathways, including NF-&#x3ba;B, JAK-STAT, cytokine signaling, and neuroimmune sensitization cascades. Autopsy-based skin analysis further demonstrated genotype-associated differences in dermal LAMP3-positive cell infiltration and CD8-positive T-cell abundance, while CD4-positive T-cell abundance and intraepidermal nerve fiber density remained unchanged across genotypes. Taken together, these findings suggest a potential association between LAMP3 variation and individual differences in peripheral pain threshold and provide biological context supporting a role for neuroimmune interactions in early sensory modulation under metabolic stress. Given the suggestive genetic evidence and indirect mechanistic data, these observations should be interpreted as exploratory and hypothesis-generating.

Humans

Protein persulfidation emerges as a conserved component of the redox response to DNA damage.

Genotoxic stress is frequently accompanied by alterations in cellular redox homeostasis; however, the mechanisms linking redox regulation to the DNA damage response (DDR) remain incompletely understood. Here, we investigated the early redox response to DNA damage induced by methyl methanesulfonate (MMS) in Saccharomyces cerevisiae, focusing on cysteine oxidative post-translational modifications (PTM). We show that activation of the DNA damage response is accompanied by rapid redox changes that occur in the absence of a generalized oxidative stress response. MMS exposure promotes selective remodeling of cysteine oxidative modifications, characterized by decreased free thiols, robust induction of protein persulfidation, and comparatively modest changes in sulfenylation. These alterations are accompanied by increased intracellular hydrogen sulfide levels, supporting the involvement of reactive sulfur species in the cellular response to DNA damage. Proteome-wide analyses revealed that cysteine oxidative modifications preferentially target proteins involved in central metabolism, nucleotide biosynthesis, and genome maintenance. Consistent with these observations, MMS-induced genotoxic stress promotes metabolic adaptation characterized by increased mitochondrial respiration, elevated ATP production, and mitochondrial morphological remodeling, linking bioenergetic adaptation to redox regulation. Importantly, perturbation of intracellular redox balance using N-acetylcysteine compromises survival under DNA-damaging conditions, supporting a functional role for redox signaling during the DDR. Finally, MMS treatment also induces protein persulfidation in mammalian cells. Moreover, exposure to etoposide, a mechanistically distinct genotoxic agent that induces DNA double-strand breaks through topoisomerase II inhibition, showed a similar trend, suggesting that protein persulfidation may not be restricted to alkylation-induced DNA damage. Together our findings identify protein persulfidation as a prominent component of the redox response to DNA damage and provide new insight into the functional interplay between mitochondrial metabolism, cysteine-based redox regulation, and genome maintenance.

Oxidation-Reduction