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Ren, X.

Publications and source records attributed to Ren, X..

At least 19 recordsLinked to original sources

The fusion gene occurrence spectrum predicts the spatial structure of chromosomes

Chromosome was "self-assembled" into a complex three-dimensional topology in the nucleus, which provided the structural basis for important biological processes such as gene expression regulation and cell differentiation. The current understanding of the three-dimensional organization of the genome is based on high-throughput sequencing and imaging technologies to visualize the conformation of chromatin in its native environment. This study proposes a new research perspective and technical means to use fusion genes to determine the interaction information and three-dimensional structure of chromosomes. This three-dimensional information provided by the fusion gene spectrum not only shows the universality of the spatial layout of chromosomes, but also increases the interpretability of the occurrence of fusion genes. The chromatin conformation capture data of multiple tissues and periods is significantly correlated with the strength of fusion genes. For example, the frequency of trans-interaction between chromosomes 11 and 17 was the highest, and the frequency of fusion gene occurrence corresponding to KMT2A on chromosome 11 was the highest. Therefore, we infer that this structural universality is a common feature of the human genome, which provides a theoretical basis and data for predicting chromosome fusion events.

cancer biology↗

Molecular Editing in Protein Degradation: From a Dual NSD2/GSPT1 Degrader to an NSD2-Selective PROTAC and a GSPT1-Selective Molecular Glue

Both NSD2 and GSPT1 represent compelling targets for anti-cancer drug discovery. Herein, we carried out single-atom modification of LLC0424, an NSD2 degrader with GSPT1 neosubstrate engagement, to yield two structurally analogous molecules with divergent modes of action: 424-ND, an NSD2-selective degrader, and 424-GD, a GSPT1-selective degrader. 424-ND drove selective NSD2 degradation and suppressed androgen receptor (AR) signaling in prostate cancer cells. 424-GD induced selective degradation of GSPT1 and upregulated the integrated stress response markers ATF4 and ATF3. Biolayer interferometry revealed distinct ternary complex cooperativity profiles in the presence of NSD2 or GSPT1, which directly correlate with the observed biased degradation activity. Molecular dynamics and metadynamics simulations showed that the compounds adopt distinct low-energy conformational ensembles with different spatial orientations, likely underlying their divergent cooperativity and selectivity. These findings demonstrate that minimal structural alteration permits precision control over degrader target selectivity, while furnishing selective chemical probes for NSD2 and GSPT1.

cancer biology↗

Dose-Dependent Effects of Low-Intensity Focused Ultrasound on Human Deep White Matter Tracts

Background: Low-intensity focused ultrasound (LIFU) is emerging as a method for anatomically specific, noninvasive, and reversible neuromodulation of deep brain structures relevant to psychopathology. A key requirement for clinical translation is evidence of graded target engagement. We examined whether LIFU applied to deep white matter tracts produces dose-dependent functional connectivity changes in healthy adults. Methods: In this preregistered, double-blind, randomized study, 35 healthy adults underwent LIFU targeting (80 s, 10% duty cycle, estimated ISPPA 2.26 W/cm2, 0.5 MHz, in a {theta}-burst pattern) of individually modeled right thalamo-prefrontal white matter tracts under two dose conditions: one and three consecutive sonications. Dose-dependent changes in resting-state functional connectivity were examined during a 30-minute poststimulation period in 31 participants. Results: One sonication acutely increased right thalamic functional connectivity with the left thalamus (28 voxels; Z = 5.48, Cohen's d = 0.61), whereas three sonications decreased connectivity with the right dorsolateral prefrontal cortex (Z = -4.05, Cohen's d = -0.45). Poststimulation time-course analysis revealed a 3-LIFU-specific linear recovery trend in the left cerebellum (Z = 4.14, d = 0.48), reflecting initial suppression followed by progressive recovery across 30 minutes. Stronger thalamo-prefrontal structural connectivity was associated with condition-specific functional connectivity changes (left frontal pole; F = 14.73, {rho}2 = 0.41). Conclusions: These findings provide initial human evidence that LIFU is well tolerated and produces dose-dependent changes in functional connectivity associated with deep white matter tract stimulation, informing parameter selection for future circuit-based mechanistic and clinical studies.

neuroscience↗

RGC-specific reversal of lipid peroxidation drives neuroprotection and vision restoration in optic nerve ischemia by targeting GPX4

Nonarteritic anterior ischemic optic neuropathy (NAION) is the leading cause of acute optic nerve related vision loss in older adults, yet no disease modifying therapy exists. Although ischemia is a defining feature of NAION, prior therapeutic efforts targeting vascular insufficiency or nonspecific oxidative stress have failed to prevent irreversible retinal ganglion cell (RGC) degeneration, underscoring an unresolved mechanistic gap between ischemic insult and permanent axonal failure. In this endeavour, we identify lipid peroxidation as an important driver of neurodegeneration in NAION. Analyses of human NAION retina, together with a rigorously validated mouse model, demonstrated a remarkable activation of phospholipid peroxidation within the retina following ischemic injury. RGC-specific overexpression of glutathione peroxidase 4 (GPX4), the only known enzyme capable of directly detoxifying phospholipid hydroperoxides within biological membranes, confers striking protection of RGC survival, axonal integrity, and visual function. We further demonstrate that mitochondrial-targeted GPX4 provides superior protection, suggesting mitochondria as a critical locus of lipid peroxidation-driven vulnerability in NAION. Leveraging real-time multiparametric in vivo imaging to directly interrogate axonal metabolism and function, we demonstrate that RGC-specific GPX4 overexpression robustly restores axonal and retinal mitochondrial abundance, improves ATP bioenergetics, and suppresses superoxide stress following optic nerve ischemia. Mitochondria-targeted GPX4 expression further restores axonal transport and retinofugal projections to central visual targets, thereby stabilizing visual pathway connectivity. Notably, these neuroprotective effects are recapitulated by Ebselen, a clinically tested GPX mimetic, identifying lipid peroxide detoxification as a translatable and imaging-validated therapeutic strategy. Collectively, this work establishes ischemia-induced lipid peroxidation as an essential driver of neurodegeneration in NAION and identifies GPX4 as a key molecular determinant of retinal ganglion cell resilience.

neuroscience↗

Flux-species sampling enables holistic exploration of biocircuit behavior

Biocircuit behavior is usually discovered by drawing uncertain kinetic parameters and simulating, but the scored phenotypes are functions of steady-state species, catalytic fluxes, dominance relations, and local response matrices. We introduce flux-species sampling (FSS), which samples that functional layer directly and algebraically inverts to parameters. This coordinate change turns regulatory modes into simple dominance chambers, gives every full-dimensional behavior-realizing regime positive measure, and can replace the sampling stage of existing pipelines without changing downstream stability or phenotype tests. A sequestration toy shows how a large species regime can collapse into a narrow parameter strip. In an enzymatic feedback motif, FSS rescues free-A* adaptation missed by parameter sampling and identifies the regime as non-Michaelian and complex-dominated. In MultiFate-N, FSS separates a sampling limitation from a structural limitation and rescues parameter sets realizing all 2N states. HighlightsO_LIFlux-species sampling (FSS) draws the control/function layer where biocircuit behavior is read C_LIO_LIFSS boxes intersect every full-dimensional behavior-realizing regime with positive measure C_LIO_LIFSS is no slower than parameter-space sampling and is a hot fix for existing pipelines C_LIO_LIFSS rescues non-Michaelian free-A* adaptation missed by parameter sampling C_LIO_LIFSS rescues the all-2N symmetric MultiFate regime missed by fixed parameter boxes C_LI eTOC blurbThis study reframes biocircuit exploration by sampling steady-state species and fluxes rather than raw parameters. The resulting flux-species coordinate exposes regulatory dominance regimes, rescues adaptation and multistability regimes missed by parameter sampling, and gives finite sampling nulls an explicit scope.

systems biology↗

Inhibition of integrin αvβ8-mediated TGFβ activation and active-TGFβ blockade promote anti-tumor immunity through distinct biological mechanisms

Transforming Growth Factor {beta} (TGF{beta}) is a potent immunosuppressor and a primary driver of resistance to cancer immunotherapy. While preclinical models have long suggested that TGF{beta} inhibition could synergize with immune checkpoint inhibitors, these effects have proven difficult to replicate in clinical settings. The highly regulated TGF{beta} pathway can be inhibited through various mechanisms, including neutralizing activated ligands or inhibiting upstream activators, such as integrins. Recent structural data demonstrated that integrin v{beta}8 can enable TGF{beta}1/3 signaling without releasing the active cytokines from their Latency-Associated Peptides, suggesting that ligand-blocking antibodies may have limited access to their epitopes. Here, we show that integrin v{beta}8 blockade, while achieving anti-tumor responses similar to those of anti-TGF{beta} antibodies, does so through a distinct mechanism of action. Anti-v{beta}8 is 3 orders of magnitude more potent at inhibiting v{beta}8-mediated TGF{beta} activity than a commonly used antibody against the mature form of the cytokine. Whereas TGF{beta} ligand inhibition has little effect on TGF{beta} signaling in tumor-draining lymph nodes (tdLN) and requires IFN{gamma} for its anti-tumor effects, v{beta}8 blockade strongly inhibits TGF{beta} signaling in tdLN and, in combination with PD-L1 blockade, drives tumor control through an IFN{gamma} -independent mechanism that strictly requires T cell egress from tdLN. Combined v{beta}8 and anti-PD-L1 blockade enhances antigen presentation in dendritic cells (DCs) and, unlike TGF{beta} ligand blockade, improves the efficiency of DC-induced T cell activation in response to cross-presented antigen. These findings suggest that v{beta}8 blockade can disable an immunologically critical source of TGF{beta} signaling that is not addressed by antibodies targeting TGF{beta} ligands, suggesting a promising new approach to TGF{beta} pathway modulation. One Sentence SummaryUnlike ligand-neutralizing antibodies, v{beta}8 blockade suppresses TGF{beta} in tdLN and boosts DC-T cell activation, a differentiated immunotherapy strategy.

immunology↗

IgG4⁺ plasma cell enrichment and {lambda}-chain-biased BCR remodeling drive low-grade autoimmunity in chronic obstructive pulmonary disease

BackgroundThis study aimed to elucidate B cell subset pathology in COPD, a poorly characterized area, with a focus on its similarities to and differences from classical autoimmune disorders. MethodsThe single-cell RNA-sequencing (scRNA-seq) data from COPD and autoimmune diseases were obtained from Gene Expression Omnibus (GEO) for comparative analyses of B cell subsets and functions via differentially expressed genes (DEGs), KEGG, protein-protein interaction (PPI), and cell-cell communication analyses. Serum IgG4 was measured by ELISA and correlated with clinical parameters. The peripheral blood B cells were sorted by flow cytometry for single-cell B cell receptor (BCR) sequencing. A v-Abl/Bcl2 pro-B cell line was stimulated with cigarette smoke extract (CSE) to assess abnormal development in vitro. ResultsIn lung tissue, IgG4+ plasma cells were enriched and expressed BCR activation/inflammatory genes and TNF/NF-{kappa}B/MAPK pathways. Serum IgG4 concentrations correlated negatively with pre-and post-bronchodilator FEV1/FVC. B cell interacted with monocytes, macrophages, fibroblasts and endothelial cells via IL-1{beta}/IL-6, integrin and chemokine signalling, contributing to chronic inflammation and remodelling. In peripheral blood, transitional T1 B cells were increased, accompanied by {lambda}-chain enrichment and increased IGLV1-47 usage, as well as enrichment of autoimmune pathways. In the bone marrow, the numbers of pre-B I cells were increased while those of small pre-B III cells were reduced, with altered expression of BCR development genes. CSE stimulation of the pro-B cell line reduced {lambda}5 expression in a concentration-dependent manner. ConclusionsThe autoimmune abnormalities in COPD appear more restricted, although IgG4 antibody generation may contribute to immune-mediated lung damage.

immunology↗

Buffered sweat microfluidics with AI-enabled translation for clinically actionable blood urea estimation and renal risk stratification

Kidney-function assessment relies on blood urea as a clinically informative metabolic marker; however, its dependence on venipuncture and centralised laboratory testing limits high-frequency monitoring and delays timely clinical intervention. Here, we report an integrated platform combining a wearable buffered microfluidic patch with a physiology-informed, data-driven calibration framework for real-time, non-invasive estimation of blood urea from microlitre-scale sweat volumes (4.79 L). By precisely regulating the release kinetics of internal buffer salts, the device stabilises the local reaction microenvironment, mitigating variability in sweat pH and flow to ensure reproducible measurement. The resulting signals are processed through an artificial intelligence (AI)-enabled analysis pipeline that integrates sweat urea with patient-specific physiological information to generate clinically interpretable outputs. In multicentre studies, sweat urea shows a strong association with blood urea across diverse cohorts, but with nonlinear and time-lagged relationships that limit direct use. The AI-enabled calibration model compensates for these effects, enabling high-fidelity estimation of blood urea (r = 0.945 versus gold-standard measurements) at clinically relevant concordance levels. The platform further identifies kidney injury with 89.1% accuracy and stratifies disease severity with 83.2% accuracy. Notably, these results demonstrate that the integration of physicochemical stabilisation and AI-enabled data-driven translation establishes sweat as a clinically actionable surrogate for renal monitoring, supporting population-level estimation and highlighting the potential for personalised longitudinal assessment, and enabling a scalable, non-invasive strategy for high-frequency kidney disease management.

biophysics↗

Interstitium-mimicking porous alveolar membranes enable physiologic aerosol transport and distinct acute-chronic lung injury responses

Barrier membranes govern transport and mechanochemical coupling in lung-on-chip systems but typically exhibit low open porosity, limited pore interconnectivity, and diffusion distances exceeding native thin septal regions. An interstitium-mimicking, alveolus-shaped poly({varepsilon}-caprolactone) membrane is developed using dual-templated nonsolvent-induced phase separation followed by controlled enzymatic pore enlargement. The resulting architecture achieves [~]40% total porosity with 97% pore interconnectivity and incorporates a locally thinned dome region ([~]2.5 {micro}m). This structure sustains cyclic deformation while increasing oxygen diffusivity fivefold compared with conventional Transwell(R) membranes under both acellular and epithelial-endothelial co-culture conditions. Integrated into an air-liquid interface platform, the membrane enables direct aerosol deposition and quantitative interrogation of cross-barrier mass transfer. Using carbonaceous nanoscale particulate matter as a model inhaled aerosol, controlled exposure induces dose-dependent oxidative, inflammatory, and genotoxic responses. Matched cumulative dose studies reveal distinct biological trajectories: acute high-dose exposure produces rapid cytotoxic stress and barrier disruption, whereas chronic low-dose exposure preserves viability yet promotes sustained DNA repair and genome-maintenance programs. Compartment-resolved analysis and therapeutic intervention further demonstrate the platforms utility for spatial and translational interrogation of lung injury. By restoring physiologically relevant diffusion distance, interconnectivity, and strain responsiveness, the interstitium-mimicking membrane advances lung-on-chip design toward functional replication of alveolar transport dynamics for studying lung injury and barrier dysfunction.

bioengineering↗

Short-Term Developmental Trajectories of Dorsal-Ventral Pathways and Their Relationships with First-Grade Learning

The first year of formal schooling is a year of foundational reading and math learning, and individual differences emerging within this single year predict academic achievement decades later. Yet, how brain changes throughout this critical year relate to individual differences in reading and math learning remains uncharacterized. In this pre-registered study (https://osf.io/97ybe), we acquired monthly both behavioral assessments of reading- and math-learning, and diffusion-weighted MRI scans to measure white matter microstructure, across the first-grade year. Behavioral learning trajectories follow either a sigmoid for reading or an inverted-U for math. Month-to-month microstructural changes in the right middle longitudinal fasciculus predicted corresponding changes in math performance, but not in reading. Findings highlight white matter microstructure as a dynamic substrate of early math learning, and reveal a more general principle: rapid changes in white-matter microstructure during the foundational learning window may be associated with distinct academic domains. FundingR01 HD114489

neuroscience↗

Intron 13 retention expands the ADAR1 isoform repertoire to rewire PKR signaling and promote tumorigenesis

For decades, the biology of ADAR1 has been framed around two major isoforms: the nuclear-enriched p110 and the predominantly cytoplasmic p150. Here, we reveal an unexpected repertoire expansion of ADAR1 isoforms that is driven by intron retention. Specifically, intron 13 (I13) can be retained in ADAR1 transcripts, conferred by an evolutionarily conserved weaker 5SS. In addition, we found that the I13 retention (I13R) is negatively autoregulated by ADAR1 through antagonizing the binding of hnRNPA1 to I13 in an editing-independent manner. Despite being sensitive to nonsense-mediated decay, I13R generates two previously uncharacterized truncated isoforms - p90 and p130, that both lack the C-terminal portion of the deaminase domain. Intriguingly, ADAR1p90 - a derivative of the canonical nuclear-enriched p110 isoform - is predominantly cytoplasmic, that effectively represses PKR and eIF2 activation through the sequestration of immunogenic double-stranded RNA (dsRNA) substrates. Furthermore, in a colorectal cancer (CRC) cohort, p90 levels are increased in most tumors relative to matched normal tissues that positively correlates with hnRNPA1 expression. Functionally, xenografts expressing ADAR1p90 grow significantly faster and larger than those expressing ADAR1p110, indicating enhanced tumorigenic potential. These findings revise the canonical view of ADAR1 isoforms, demonstrating that intron retention can generate alternative isoforms with augmented functions that tumors readily exploit. One Sentence SummaryThe conserved retention of I13 in ADAR1 transcripts gives rise to previously uncharacterized C-terminal truncated cytoplasmic ADAR1 isoforms, p90 and p130, which, although devoid of catalytic activity, sequester immunogenic dsRNA substrates, thereby preventing PKR binding and downstream activation of eIF2.

cell biology↗

A novel reporter mouse for astrocyte-derived extracellular vesicles reveals trafficking of cargo to neuronal mitochondria

Extracellular vesicles (EVs) mediate intercellular transfer of lipids, proteins, and nucleic acids between nearly all cell types. We previously showed that astrocyte-derived EVs modulate neuronal mitochondria in vitro, but whether endogenous astrocytic EVs are trafficked to neuronal mitochondria in vivo remained unknown. To address this, we generated an EV reporter mouse, Aldh1l1-Cre; CD9-tGFPfl/fl, in which astrocyte-secreted EVs are labeled with a CD9-turboGFP fusion protein (CD9-tGFP). Astrocyte-specific expression of CD9-tGFP was verified in brain tissue and isolated EVs, comprising 13.2 {+/-} 1.6% of total brain EVs. In primary glial cultures, CD9-tGFP was restricted to astrocytes, localizing to vesicular compartments and cell protrusions (filopodia and cilia), with 89.3 {+/-} 2.2% of astrocyte-derived EVs carrying the label. These EVs were enriched with the sphingolipid ceramide, consistent with its co-distribution with CD9-tGFP in astrocytic cell protrusions. In the cortex, hippocampus, and cerebellum, CD9-tGFP was predominantly detected in astrocytic processes co-labeled with GLAST1 and GFAP, forming contacts with laminin-positive capillaries and parvalbumin-positive neurons. CD9-tGFP-labeled EVs were detected inside capillaries and neurons, and super-resolution STED microscopy revealed partial overlap with neuronal mitochondria. Live-cell spinning disk confocal imaging and AI-assisted proximity analysis confirmed uptake of CD9-tGFP EVs by neuronal cells and trafficking of their cargo to mitochondria in vitro. Biochemical isolation of synaptic and non-synaptic mitochondria confirmed EV-derived cargo on mitochondria in vivo, with 3-fold higher association of CD9-tGFP with synaptic than non-synaptic mitochondria. Together, these findings validate the Aldh1l1-Cre; CD9-tGFPfl/fl reporter mouse as a powerful tool for tracking astrocyte-derived EVs in vivo and provide direct evidence that their cargo is preferentially trafficked to synaptic mitochondria. Graphical AbstractAstrocyte-derived extracellular vesicles target neuronal mitochondria in vivo O_FIG O_LINKSMALLFIG WIDTH=156 HEIGHT=200 SRC="FIGDIR/small/718987v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@174d92aorg.highwire.dtl.DTLVardef@5d8248org.highwire.dtl.DTLVardef@114483borg.highwire.dtl.DTLVardef@924d55_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

A unified spatial transcriptome profiling of ten mouse organs

Spatial transcriptomics has enabled numerous deep learning models in this area, and training them requires large amounts of high-quality data, especially expression matrices paired with histological images. Here, we present a unified spatial transcriptomic dataset generated using the Stereo-seq platform, covering 10 mouse organs--including brain, kidney, lung, thymus, large intestine, skin, spleen, ovary, testis, and uterus--encompassing 23 tissue sections generated from 21 chips, each with matched ssDNA or H&E staining images. The dataset comprises single-cell-resolution (cell-bin) or square bin-50 (25 {micro}m x 25 {micro}m) expression matrices for each sample, accompanied by corresponding cell type annotations. Annotation robustness was further supported by concordance across different sections of the same tissue and corroboration with canonical marker gene expression patterns. Finally, we compared the characteristics of the cell-bin and bin-50 expression matrices and demonstrated the advantages of cell-bin resolution for cell annotation. This dataset provides a standardized resource for spatial transcriptomics method development, benchmarking, and multimodal analysis.

bioinformatics↗

FOXA1 preserves cell polarity and restrains lysosome biogenesis in non-small cell lung adenocarcinoma

BackgroundThis study investigates the role of the pioneer transcription factor FOXA1 as a master gene in sustaining epithelial cell polarization in early-stage lung adenocarcinoma. The partial loss of FOXA1 is explored to determine if it will affect plasticity and progression of lung adenocarcinoma. The study also addresses the transcriptional circuitry that links polarity defects to lysosome homeostasis. MethodsA multiomics approach was used to define the status of the chromatin in epithelial and mesenchymal states of A549 adenocarcinoma cells obtained with a newly synthetized TGF-{beta} receptor inhibitor or TGF-{beta} respectively. The study leveraged ATAC-seq, RNA sequencing, Cut&Tag sequencing of FOXA1 and histone marks profiling. The functional impact of FOXA1 was examined by partial silencing in vitro and by heterozygous FOXA1 deletion in a KrasG12D mouse model. Three-dimensional organoid culture, high-resolution electron microscopy, spatial transcriptomics and multiplex immunohistochemistry assessed carcinoma cell polarity, proliferation, the tumor microenvironment and organelle content. Group differences were evaluated with two-tailed t tests or one-way analysis of variance. ResultsFOXA1 binding and expression were highest in cells harboring an epithelial phenotype. In mouse KrasG12D LUAD tumors FOXA1 marked polarized, CDH1-positive cells; heterozygous loss diminished CDH1, disrupted apical-basal architecture, lowered organoid-forming efficiency and remodeled the immune microenvironment. Spatial transcriptomics and ultrastructural analyses showed that FOXA1-deficient carcinoma cells accumulated lysosomes, down-regulated vesicle fusion genes of the SNARE family and activated the lysosomal CLEAR gene network. FOXA1 occupied enhancers of lysosome-associated genes and competed with the transcription factor TFE3, thereby suppressing transcription of cathepsin B and cathepsin C and restricting lysosome biogenesis. ConclusionsFOXA1 is a central regulator that preserves epithelial cell polarity and limits lysosome formation in lung adenocarcinoma. Targeting the FOXA1-TFE3-lysosome axis may affect tumor plasticity and provide new therapeutic opportunities.

cancer biology↗

Ceramide-rich extracellular vesicles as pathogenic biomarkers in traumatic brain injury

Extracellular vesicles (EVs) contribute to the damage caused by traumatic brain injury (TBI) and can cross the blood-brain barrier (BBB). We analyzed plasma-derived EVs from human TBI patients to identify factors potentially contributing to TBI pathology. EVs were isolated using membrane affinity (ExoEasy) and size exclusion chromatography (iZone), both yielding CD9(+) and CD63(+) EVs with minimal contamination by serum albumin and apolipoprotein. Immunoblotting detected GFAP in TBI but not control EVs, indicating astrocyte-derived EVs crossing the BBB. Proteomic analysis and immunoblotting of EVs from TBI samples identified C-reactive protein and 14-3-3 proteins, which were not detected in control EVs, indicating inflammation associated with TBI. Lipidomic analysis showed ceramide enrichment in TBI EVs, validated by anti-ceramide immunoprecipitation. In a mouse closed head-controlled cortical impact model, brain EVs similarly showed elevated ceramide, confirming ceramide-rich EV release after TBI. Immunocytochemistry localized acid sphingomyelinase (ASM), a ceramide-generating enzyme, to ependymal cilia, suggesting these sites as a potential source of EVs. This was further supported by the detection of ASM in both brain- and plasma-derived EVs, along with the ciliary marker Arl13b in the brain. To assess function, we treated murine neuronal (N2a) cells with TBI EVs. Transcriptomics and STRING analyses revealed enrichment of mitochondrial-associated transcripts. Immunoblotting showed increased p53 and voltage-dependent anion channel 1 (VDAC1), which mediate ceramide-induced apoptosis. Seahorse assays showed that TBI EVs suppressed glycolysis, as indicated by reduced ECAR, while mitochondrial respiration (OCR) remained unchanged. LDH assays further indicated that TBI EVs were more neurotoxic than control EVs. Together, these findings identify ceramide-rich EVs as plasma biomarkers of TBI-induced inflammation, potential mediators of neuronal mitochondrial dysfunction, and pharmacological targets to prevent TBI-induced damage.

neuroscience↗

The motive cocktail in childrens altruistic behaviors

Children frequently intervene in social conflicts by punishing violators or helping victims, yet the motivational mechanisms underlying such third-party altruistic behavior remain poorly understood. It remains unclear how children balance fairness concerns against self-interest, how these motivations interact with intervention costs and impact on outcomes, and whether gender and individual differences reflect distinct motivational structures. Here, we applied the motive cocktail model, which assumes that altruistic behavior arises from multiple prosocial motives, to dissociate motivations underlying third-party interventions. We studied 229 children aged 8-12 years (123 boys), an age when fairness and inequality aversion are reliably expressed. The third-party intervention task manipulated inequality between others, the personal cost of intervention, its impact on outcomes, and the form of intervention (punishment versus helping). Children intervened more as inequality increased and less as intervention costs rose, indicating a trade-off between moral benefits and self-interest. Gender differences emerged only under high-cost and high-impact conditions, with boys engaging in more punishment interventions. The motive cocktail model outperformed alternative models and revealed that boys showed stronger aversion to disadvantageous inequality and a greater tendency to reverse victims disadvantage than girls. Clustering analyses further identified distinct motivational profiles within each gender. These findings demonstrate that childrens third-party altruistic behavior is governed by multiple dissociable motives. This study provides a mechanistic account of how social motivations are organized and weighted during late childhood.

neuroscience↗

Nonanticoagulated Heparin Derivatives Mediate Goblet Cell Differentiation to Restore the Mucosal Barrier for Ulcerative Colitis Therapy

Epithelial mucus barrier dysfunction is a pathological hallmark of ulcerative colitis (UC), yet current clinical therapeutic strategies primarily suppress inflammation, lacking reliable approaches for restoration of the mucosal layer. Here, through a systematic screen of our established library of deanticoagulated heparins, we identified NALHP, a non-anticoagulant low-molecular-weight heparin derivative, and its representative fraction S6 as orally active epithelial repair-promoting glycans. NALHP/S6 restored crypt architecture, mucus production and epithelial barrier integrity in experimental colitis. In UC patient-derived colonic organoids, NALHP/S6 reduced aberrant stem/proliferative programs while promoting secretory, absorptive and junctional maturation. Single-cell transcriptomics and temporal validation identified a transient repair-secretory transitional state (RSTS) positioned between classical Wnt-associated stemness and mature barrier-forming epithelial states. Transcriptomic analysis revealed coordinated attenuation of Wnt and Notch signaling, whereas pharmacological reactivation of these pathways opposed NALHP/S6-induced epithelial state progression. These findings define mucosal repair as a regulated epithelial-state transition and identify NALHP/S6 as glycan-based modulators capable of restoring this progression in UC epithelium.

pathology↗

Cell type-resolved proteomics reveals intra- and intercellular signalingin Alzheimers disease

Alzheimers disease (AD) arises from pathological interactions among diverse brain cell types, but cell-specific proteomic changes remain underexplored. Here, we present deep proteomic profiling of sorted or proximity-labeled brain cells from AD mouse models (5xFAD and AppNL-G-F) at multiple ages, quantifying 13,411 proteins in microglia (three subtypes), astrocytes, oligodendrocyte precursor cells, and neurons. We identified 3,028 differentially abundant proteins across these cell types, the majority of which were not detected in bulk proteomic datasets, and constructed cell type-specific networks to define functional modules and hub proteins. Comparison with transcriptomic data revealed that [~]30% of proteomic changes are RNA-independent. Further analyses uncovered cross-cell type signaling proteins conserved in human AD brains, such as pleiotrophin (Ptn), which is transcriptionally enriched in astrocytes but accumulates in microglia. Importantly, recombinant PTN directly activates induced microglia-like (iMG) human cells. Thus, these findings provide a comprehensive cell type-resolved proteomic atlas of AD models, highlighting novel intra- and intercellular signaling events. HighlightsO_LIA high-resolution cell type-resolved proteomic atlas of Alzheimers disease mouse models C_LIO_LI[~]3,000 cell type-specific protein alterations identified beyond bulk tissue analyses C_LIO_LIProteomic profiling of microglial subtypes reveals subtype-specific changes in Alzheimers disease C_LIO_LIAstrocyte-microglia signaling is highlighted and validated through PTN-mediated interactions C_LI

neuroscience↗