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Wei, Z.

Publications and source records attributed to Wei, Z..

At least 73 records · Page 4Linked to original sources

Glis3 is a modifier of cyst progression in autosomal dominant polycystic kidney disease

BackgroundAutosomal dominant polycystic kidney disease (ADPKD) is caused by mutations affecting polycystin-1 (PC1) or -2 (PC2). The existence of a cilia-dependent cyst activation (CDCA) pathway has been identified by demonstrating that structurally intact primary cilia are crucial for cyst growth following loss of polycystins. We previously used translating ribosome affinity purification (TRAP) RNA-Seq on pre- cystic mouse kidneys to determine the translatome that meet the criteria for CDCA and identified Glis2 as an early effector of polycystin signaling. Here, we investigate the potential role of Glis3 in ADPKD, which, while not transcriptionally altered, encodes a cilia-localized transcription factor belonging to the same family of genes as Glis2. MethodsWe used live cell confocal imaging to study the subcellular localization of Glis3 in the presence or absence of Pkd1. We used Glis3 conditional knockout mice to investigate the genetic interaction between Glis3 and Pkd1. Changes in gene expression and chromatin accessibility were assessed by RNA-Seq and ATAC-Seq on an allelic series of Glis3 and Pkd1 kidney selective inactivation models at 7-weeks age to evaluate the function of Glis3. ResultsThe ciliary localization of Glis3 is not affected by Pkd1 mutation status. Kidney selective Glis3 by itself does not affect kidney structure or function, but dual inactivation of Glis3 and Pkd1 significantly worsen polycystic kidney disease. Integration of transcriptomic profiling and chromatin accessibility assays suggested that kidney tubule specific Glis3 inactivation results in dysregulated fatty acid metabolism and circadian. ConclusionsGlis3 is a primary cilium localized transcription factor that genetically interacts with Pkd1 and modifies kidney epithelial cell metabolism and circadian function.

genetics↗

OriGene: A Self-Evolving Virtual Disease Biologist Automating Therapeutic Target Discovery

Here, we present OriGene, a self-evolving multi-agent system that functions as a virtual disease biologist, systematically identifying original and mechanistically grounded therapeutic targets at scale. OriGenes architecture integrates over 600 specialized tools through a Model Context Protocol (MCP), enabling it to reason across diverse data modalities including genomics, protein networks, pharmacology, clinical records and literature evidence, to generate and prioritize target discovery hypotheses. We implemented a strategy combining a knowledge graph-based Tool RAG with an advanced agent selection mechanism to enable dynamic, context-aware tool deployment. Through a self-evolving framework, OriGene continuously integrates human and experimental feedback to iteratively refine its core thinking templates, tool composition, and analytical protocols, thereby enhancing both accuracy and adaptability over time. To comprehensively evaluate its performance, we established TRQA, an original benchmark comprising over 1,900 expert-level question-answer pairs spanning a wide range of diseases and target classes. OriGene consistently outperforms human experts, leading research agents, and state-of-the-art large language models in accuracy, recall, and robustness, particularly under conditions of data sparsity or noise. Critically, OriGene nominated previously underexplored therapeutic targets for liver (GPR160) and colorectal cancer (ARG2), which demonstrated significant anti-tumor activity in patient-derived organoid and tumor fragment models mirroring human clinical exposures. These findings demonstrate OriGenes potential as a scalable and adaptive platform for AI-driven discovery of mechanistically grounded therapeutic targets, offering a new paradigm to accelerate drug development.

bioinformatics↗

Bacterial Community Structure and Diversity of Common Mosquito Species in Chengdu: Insights from PacBio Third-Generation

Mosquitoes, as critical vectors of diseases such as Japanese encephalitis, dengue fever, and yellow fever, pose significant public health risks in Chengdu, a subtropical city in southwestern China. This study integrated ecological surveillance and PacBio third-generation sequencing to characterize the symbiotic microbiota of four dominant mosquito species (Aedes albopictus, Culex pipiens, Culex tritaeniorhynchus, and Armigeres subalbatus) across urban and rural habitats. From 2020 to 2024, mosquito density monitoring revealed spatial heterogeneity(Aedes albopictus, Culex pipiens, Culex tritaeniorhynchus, and Anopheles sinensis), with outer ring areas exhibiting the highest density (34.69 mosquitoes per trap), while central urban zones had the lowest (3.60). Sequencing identified 717 high-quality Amplicon Sequence Variants (ASVs), with Aedes albopictus harboring the most unique bacterial species (191). Beta diversity analysis demonstrated distinct microbial clustering among species, driven by Pseudomonadota dominance (54.27-93.89%) and variations in secondary phyla (Bacteroidota, Campylobacterota). Functional prediction via KEGG highlighted elevated human disease-associated pathways in Ae. albopictus, contrasting with reduced environmental adaptation activity. Notably, Wolbachia (clade B) and Klebsiella variicola exhibited species-specific abundance patterns, underscoring their roles in pathogen suppression and public health risks. Unclassified taxa (norank_d Bacteria, Candidatus_Hydrogenedentes) clustered near novel mosquito-associated spirochetes, suggesting underexplored functional microbiota. This study provides foundational data for understanding mosquito-microbe interactions and informs strategies for mitigating vector-borne disease. Author SummaryMosquito-borne diseases such as dengue fever and Japanese encephalitis pose severe public health risks in subtropical regions, yet critical gaps remain in understanding how mosquito-associated microbes influence disease transmission in under-resourced areas. Chengdu, a megacity in southwestern China, faces unique challenges due to rapid urbanization, climatic suitability for mosquito proliferation, and disparities in public health infrastructure compared to eastern coastal regions. This study integrates five years of ecological surveillance (2020-2024) and PacBio third-generation sequencing to map mosquito density patterns and characterize symbiotic bacterial communities in four dominant mosquito species (Aedes albopictus, Culex pipiens, Culex tritaeniorhynchus, and Armigeres subalbatus). Key findings reveal stark spatial heterogeneity in mosquito density, with rural outer-ring areas harboring 10-fold higher densities (34.69 mosquitoes/trap) than urban centers. Notably, Aedes albopictus exhibited the highest diversity of unique symbiotic bacteria (191 species), including Wolbachia (clade B), known to suppress arboviruses like dengue. Conversely, Armigeres subalbatus carried high abundances of Klebsiella variicola, an emerging human pathogen linked to severe infections. Functional analyses further highlighted elevated human disease-associated pathways in Ae. albopictus, underscoring its dual role as a disease vector and microbial reservoir. This work provides the first comprehensive baseline data on mosquito-microbe interactions in Chengdu, identifying actionable targets for biocontrol (e.g., leveraging Wolbachia) and early-warning systems for pathogen surveillance. By bridging ecological, molecular, and public health perspectives, our findings offer critical insights for mitigating neglected tropical diseases in subtropical regions where socioeconomic disparities intersect with high disease burdens.

microbiology↗

A Universal 6iL/E4 Culture System for Deriving and Maintaining Embryonic Stem Cells Across Mammalian Species

The derivation of authentic embryonic stem cells (ESCs) from diverse mammalian species offers valuable opportunities for advancing regenerative medicine, studying developmental biology, and enabling species conservation. Here, we report the development of a robust, serum-free culture system, termed 6iL/E4 that enables the derivation and long-term self-renewal of ESCs from multiple mammalian species, including mouse, rat, bovine, rabbit, and human. Using systematic signaling pathway analysis, we identified key regulators--including GSK3, STAT3, PDGFR, BRAF, and LATS--critical for ESC maintenance across species. Additionally, inducible expression of KLF2 and NANOG enhances the naive pluripotency and chimeric potential of bovine ESCs. The E4 medium also supports stable ESC growth while minimizing lineage bias. These findings reveal conserved principles underlying ESC self-renewal across divergent mammalian species and provide a universal platform for cross-species stem cell research, disease modeling, and biotechnology applications. In BriefWang et al. developed 6iL/E4, a serum-free system sustaining ESCs from mouse, rat, bovine, rabbit, and human. These findings reveal conserved fundamental mechanisms governing ESC self-renewal across diverse mammalian species. HighlightsO_LIDeveloped 6iL/E4 system for ESC derivation across five mammalian species. C_LIO_LIPDGFR signaling inhibition as critical for ESC derivation across species. C_LIO_LIE4 medium improves ESC maintenance and avoids neural bias of traditional N2B27. C_LIO_LIInducible KLF2/NANOG enhances naive pluripotency and chimera formation in bovine. C_LI

cell biology↗

Study on Liver Sinusoidal Endothelial Cell Fenestrations Based on Cellular Omics-Structure Integration Technology and Its Application in Metabolic Diseases

This study developed a new Cellular Omics-Structural Integration (COSI) technology platform to address the limitation of traditional technologies in simultaneously obtaining gene expression profiles and super-resolution cellular structural information at the single-cell level. The platform comprises three core functional modules: (1) a single-cell transcriptomics and super-resolution fluorescence microscopy integration module that enables simultaneous acquisition of gene expression profiles and super-resolution fluorescence images at the single-cell level; (2) an electron microscopy and super-resolution fluorescence microscopy integration module with deep learning resolution enhancement that further gives fluorescence image high resolution features; and (3) a comprehensive analysis module that integrates transcriptomic data with enhanced super-resolution morphological data. Application of this technology to primary liver sinusoidal endothelial cells successfully achieved efficient matching and analysis of ultrastructural information and gene transcription data at the single-cell level, revealing associations between specific genes and endothelial cell fenestration formation. Through correlation analysis and multivariate statistical methods, we identified specific gene sets associated with fenestration number and average area. Validation in published non-alcoholic steatohepatitis (NASH) and diabetic mouse models demonstrated that these gene sets can effectively assess disease status and drug intervention efficacy, with fenestration number-related gene sets showing significant reduction in NASH and time-dependent changes in response to diabetes treatments. These findings not only expand our understanding of the mechanisms underlying liver and kidney endothelial cell fenestration formation but also provide novel molecular markers and potential therapeutic targets for early diagnosis and treatment evaluation of metabolic diseases. As a fundamental research tool, COSI technology fills critical gaps in existing spatial omics and cellular biology research, particularly for studying cellular structures lacking specific markers, and demonstrates significant potential for clinical applications in chronic metabolic diseases.

systems biology↗

A Unique Role for the Hippocampus in Cue Integration During Human Spatial Navigation

It is a central question in cognitive neuroscience how the brain integrates diverse sensory inputs to improve cognitive performance. This study investigated this question in the domain of human spatial navigation using high-field fMRI, a novel navigation task, and desktop virtual reality. Participants learned and retrieved spatial locations using landmarks alone (landmark condition), visual self-motion cues alone (i.e., optic flow; self-motion condition), or both cues together (combination condition). Behaviorally, participants benefited from cue integration. fMRI analyses revealed a cue integration effect in the hippocampus, which displayed positional coding only in the combination condition, and only in participants who showed behavioral evidence of cue integration. Notably, the posterior hippocampus exhibited stronger positional coding in the combination condition than in both single-cue conditions. Additionally, positional coding in the hippocampus predominantly reflected actual, rather than self-reported, locations, suggesting relatively early involvement in the cue integration process. These findings suggest that the hippocampus supports precise memory-guided navigation by integrating different spatial cues, a function beyond simple spatial representation. More broadly, this work helps reconcile the longstanding debate regarding the hippocampuss role in spatial navigation versus episodic and relational memory, facilitating a unified understanding of hippocampal function.

neuroscience↗

Tracing Siderophore Precursors to Primary Metabolism for Ecological Applications

Microbial fitness depends on balancing between primary metabolism supporting basic survival, and secondary metabolism producing metabolites for environmental adaptation. These two systems are interconnected, with most secondary metabolites deriving from primary metabolic precursors. However, systematic frameworks for studying their relationships across diverse microbes remain limited. Using siderophores--iron-chelating secondary metabolites crucial for microbial competition--as a model, we developed a stepwise "siderophore-monomer-precursor-pathway analysis" framework to trace the biosynthetic connections from siderophore structures to primary metabolism. We applied this framework to an expanded SIDERITE database containing 1018 siderophore structures. To demonstrate practical applications, we identified specific precursors utilized by the beneficial rhizobacterium Bacillus amyloliquefaciens but not by the plant pathogen Ralstonia solanacearum. Supplementing these precursors under iron-limited conditions enhanced both siderophore production in B. amyloliquefaciens and its inhibitory activity against R. solanacearum. This work establishes a direct link between primary metabolism and siderophore-mediated microbial interactions, offering new strategies for pathogen suppression through targeted metabolic interventions.

biochemistry↗

A molecular circuit regulates fate plasticity in emerging and adult AT2 cells

Alveolar AT1 and AT2 cells are vital for lung gas exchange and become compromised in several diseases. While key differentiation signals are known, their emergence and fate plasticity are unclear. Here we show in the embryonic lung that single AT2s emerge at intermediate zones, extrude, and connect with nearby epithelium via interlumenal junctioning. We observe that AT2s retain fate plasticity until the bZIP transcription factor C/EBP suppresses Notch signaling at a novel Dlk1 enhancer. Both Dlk1 and Cebpa are regulated by the polycomb repressive complex (PRC2), which together form a "pulse generator" circuit that times Dlk1 expression and thus Notch activation, resulting in a "salt and pepper" pattern of AT1 and AT2 fate. In injured adult lungs, C/EBP downregulation is required to re-access AT2 fate plasticity and is mediated by the dominant negative C/EBP family member CHOP. Finally, Cebpa loss also activates a "defender" AT2 state, distinct from its reparative state, and we propose AT2s toggle between either state following infection to protect and repair alveoli.

developmental biology↗

Anks3 mediates cilia dependent polycystin signaling and is essential for adult kidney homeostasis

The existence of a cilia-dependent cyst activation (CDCA) pathway underlying autosomal dominant polycystic kidney disease was identified by showing that cyst progression following loss of polycystins is significantly suppressed by removal of structurally intact cilia. We applied translating ribosome affinity purification RNASeq on pre-cystic mouse kidneys to determine a cell-autonomous in vivo translatome associated with CDCA and identified Glis2 as an early effector of polycystin signaling. Here, to discover additional components of CDCA, we used polycystin-dependent Glis2 expression as a functional readout and identified Anks3, from the CDCA pattern translatome, as a candidate cytosolic regulator of polycystin signaling. Anks3 regulates polycystin-dependent Glis2 expression both in vitro and in vivo. Anks3 also undergoes polycystin-dependent changes in phosphorylation state. Inactivation of Anks3 in Pkd1 mouse models suppresses cyst progression, but also results in rapidly progressive kidney injury independent of polycystins. Anks3 inactivation also normalizes a broader spectrum of polycystin-dependent CDCA translatome changes. These findings define Anks3 as a central regulator of cilia dependent polycystin signaling, functioning downstream of cilia and polycystins and upstream of Glis2, and show that Anks3 has broader functions in maintaining renal structural and functional homeostasis.

genetics↗

Cell type-specific contributions to impaired blood-brain barrier and cerebral metabolism in presymptomatic 5XFAD mice

Altered cerebral metabolism and blood-brain barrier (BBB) dysfunction are emerging as critical contributors to the preclinical phase of Alzheimers disease (AD), underscoring their role in early pathogenesis. To identify sensitive biomarkers before irreversible neuronal loss and cognitive decline, we examined 5XFAD mice at 3 months of age by applying multiple advanced MRI techniques. Arterial spin tagging based MRI revealed increased BBB permeability and water extraction fraction, indicating compromised BBB integrity at the early stage of pathogenesis in 5xFAD mice. Despite preserved cerebral blood flow, a decreased unit mass cerebral metabolic rate of oxygen (CMRO2) was evident in the same cohorts of 5XFAD mice. Interestingly, a region-specific decrease of tissue pH values was detected in the hippocampus of these 5XFAD mice by creatine chemical exchange saturation transfer MRI. Elevated neuronal H4K12 lactylation in the hippocampus supports the reduced pH values. To further dissect the cellular and molecular mechanisms underlying these MRI-detectable changes in 5XFAD mice, we conducted single-nucleus RNA sequencing (snRNA-Seq) with optimized blood vessel enrichment protocols. Our results revealed cell type-specific transcriptomic changes in the hippocampus of 3-month-old 5XFAD mice, including downregulation of synaptogenesis and synaptic transmission genes in the CA1 and dentate gyrus excitatory neurons, impaired endothelial gene expression linked to brain barrier function and angiogenesis, altered innate immune response genes in astrocytes, as well as upregulation of cholesterol biosynthesis and metabolism genes in the CA1 excitatory neurons. These findings underlie the intricate interplay between BBB disruption and metabolic dysregulation before the onset of cognitive decline in AD. Our study demonstrates that BBB dysfunction and cerebral metabolic alterations preceded brain hypoperfusion and cognitive decline, emphasizing potential molecular pathways for early intervention. These findings, once validated in human studies, could significantly enhance early diagnosis and inform novel therapeutic strategies targeting early AD pathogenesis.

neuroscience↗

Inulin reduces Ralstonia invasion by promoting cooperation between Lysinibacillus sphaericus and Pseudoarthrobacter spp.

In field production, beneficial microbial agents are typically applied along with key resources that beneficial microbes prefer to utilize. This practice aims to help the beneficial microbes colonize the field and exert their disease resistance functions. However, the mechanisms by which these key resources influence the colonization and disease resistance effects of beneficial microbes remain unknown. In this study, we found that inulin can enhance the growth capacity of Lysinibacillus sphaericus HR92 and its ability to inhibit Ralstonia solanacearum. Further investigation revealed that inulin can enhance strain HR92s flagellar assembly, bacterial chemotaxis, fatty acid metabolism, and siderophore synthesis capabilities, ultimately improving strain HR92s effectiveness in controlling bacterial wilt. Moreover, adding inulin to the soil can enrich Pseudarthrobacter strains. This genus enhances the expression of genes involved in the synthesis of the antibacterial substance HR92, and competes for nutrients with Ralstonia solanacearum, thereby further inhibiting the occurrence of bacterial wilt disease. Additionally, the combination of inulin and Pseudarthrobacter strains upregulates the valine and leucine pathway genes in strain HR92. These genes play a crucial role in the synthesis of surfactin and the antimicrobial VOC 3-methyl-1-butanol. We have demonstrated that the addition of key resources not only enhances the control efficacy of beneficial bacteria against soil-borne diseases but also enriches the "helpers" of beneficial bacteria in soil. ImportanceRalstonia solanacearum is a plant pathogen that can cause bacterial wilt in several important crops. Given the limitations of beneficial bacterial inoculation, we propose a strategy to enhance the biocontrol efficacy of beneficial microorganisms by utilizing key resources. In this study, we demonstrate that key resources inulin can improve the biological control effects of beneficial bacteria, thereby maintaining plant health. Furthermore, we found that increasing the concentration of inulin altered the diversity of the rhizosphere microbiota and specifically enriched the abundance of Pseudarthrobacter, which compete with pathogens for nutrients on one hand and, on the other hand, synergize with inulin to enhance the biocontrol efficacy of the beneficial bacterium HR92. Together, our study reveals that key resources can enhance the biocontrol efficacy of beneficial bacteria and enrich potential beneficial bacteria in resident microbial communities, further reducing tomato diseases.

microbiology↗

Fleming: An AI Agent for Antibiotic Discovery in Mycobacterium Tuberculosis

Antibiotic development is challenged by high costs and failure rates. Artificial intelligence (AI) holds promise to overcome these challenges by predicting inhibitory properties of novel compounds, generating new candidates, and contextualizing property predictions in the biological background. Fleming is an integrative AI agent that explores novel chemical space to identify lead compounds meeting multiple criteria. The discriminative and generative AI models for Mycobacterium tuberculosis (Mtb) inhibition were trained on a set of 114,900 diverse compounds and fragments based on in vitro growth inhibition. We combined both models as well as molecular optimization, ADMET prediction and literature search functions to make Fleming an integrated agent for Mtb preclinical lead identification. Fleming has 17% higher discrimination between known Mtb leads and leads for other diseases than a generic LLM agent along with 13% higher discrimination than molecular property prediction alone on challenging ADMET tasks. Fleming demonstrates an 83% in vitro hit rate of predicted inhibition and a 100% hit rate of de novo generative design. Flemings generative designs also demonstrate an 83% rate of favorable ADMET profiles. Fleming is an integrative AI agent able to explore new regions of the chemical space to select lead compounds that simultaneously meet several desirable criteria.

bioinformatics↗

Dissecting Opioid Effects in Cell-Cell Communication Within the Ventral Tegmental Area

Opioid use disorders (OUD) exacerbate the complexity of neurocognitive impairments and neurodevelopmental disorders, with poorly understood molecular mechanisms at the intercellular communication level. This study utilized single-nuclei RNA sequencing (snRNA-seq) data from the SCORCH (Single-Cell Opioid Responses in the Context of HIV) program, examining brain samples from 95 donors, including individuals with and without a history of opioid abuse, to explore the cellular communication networks within the ventral tegmental area (VTA). Our analysis, using CellChat to quantify interactions based on validated ligand-receptor pairs, revealed a significant reduction in overall cell-cell communication (CCC) in subjects with opioid abuse compared to controls. Interestingly, despite this reduction, specific communication pathways, particularly involving NRXN signaling between non-dopaminergic neurons and oligodendrocyte progenitor cells, were markedly enhanced in the opioid group. These findings suggest opioid-induced selective alterations in synaptic networking, potentially contributing to the addiction pathology and offering new insights into the molecular underpinnings of opioid-related neurocognitive dysfunction. This work expands our understanding of the mechanisms through which substance use disorders and HIV may synergistically impact brain function through altered cellular communication networks, potentially revealing novel targets for therapeutic intervention.

bioinformatics↗

Dysregulated Gene Regulatory Networks in Substance Use Disorder and HIV Infection: Insights from Single-Cell Genomics

Opioid use disorders (OUD) exacerbate the complexity of neurocognitive impairments and neurodevelopmental disorders, with poorly understood molecular mechanisms at the gene regulatory level. This study utilized single-nuclei RNA sequencing (snRNA-seq) data from the SCORCH (Single-Cell Opioid Responses in the Context of HIV) program, examining brain samples from 95 donors, including individuals with and without a history of opioid abuse, to explore the gene regulatory networks within the ventral tegmental area (VTA). While traditional differential gene expression analysis identified some significantly altered genes, including downregulation of FOS (p = 1.105e-3) in astrocytes from opioid users, our network-based approach revealed more profound disruptions in regulatory relationships. Most notably, correlation network analysis identified substantial alteration in FOS-centered regulatory networks, including complete loss of the FOS-NR4A1 connection despite unchanged NR4A1 expression levels. These findings suggest opioid-induced selective alterations in intracellular gene regulation, potentially contributing to addiction pathology and offering new insights into the molecular underpinnings of opioid-related neurocognitive dysfunction. This work expands our understanding of the mechanisms through which substance use disorders and HIV may synergistically impact brain function through altered gene regulatory networks, potentially revealing novel targets for therapeutic intervention.

systems biology↗

Whole-brain, all-optical interrogation of neuronal dynamics underlying gut interoception in zebrafish

Internal signals from the body and external signals from the environment are processed by brain-wide circuits to guide behavior. However, the complete brain-wide circuit activity underlying interoception--the perception of bodily signals--and its interactions with sensorimotor circuits remain unclear due to technical barriers to accessing whole-brain activity at the cellular level during organ physiology perturbations. We developed an all-optical system for whole-brain neuronal imaging in behaving larval zebrafish during optical uncaging of gut-targeted nutrients and visuo-motor stimulation. Widespread neural activity throughout the brain encoded nutrient delivery, unfolding on multiple timescales across many specific peripheral and central regions. Evoked activity depended on delivery location and occurred with amino acids and D-glucose, but not L-glucose. Many gut-sensitive neurons also responded to swimming and visual stimuli, with brainstem areas primarily integrating gut and motor signals and midbrain regions integrating gut and visual signals. This platform links body-brain communication studies to brain-wide neural computation in awake, behaving vertebrates.

neuroscience↗

Altered Interpersonal Neural Synchronization during Social Interaction After Shared Excluded Experiences in Depressed Adolescents

BackgroundMajor depressive disorder (MDD) is common in adolescents, and the special development stage, during which adolescents brain and neuroendocrine system develop intensively, makes it subtly difficult to develop prevention and treatment strategies for depressed adolescents compared with depressed adults. Meanwhile, public psychosocial stressors significantly influence adolescents mental health and social interaction, rendering it essential to explore how a shared psychosocial stressor, i.e., shared excluded experiences, influences social interaction in depressed adolescents. MethodsWe designed a 4-player cyberball game to probe adolescents responses to shared excluded experiences and explore the underlying interpersonal neural synchronization (INS) with functional near-infrared spectroscopy (fNIRS). ResultsWe found that shared excluded experiences could enhance adolescents social interaction preferences but decreased INS in each pair of excluded adolescents, which indicates a reduced willingness to interact with others after the exclusion. However, no significantly different behavioral responses to the shared excluded experiences were found in depressed adolescents compared to adolescents as healthy controls (HC). Further analyses revealed that adolescents with MDD experienced more negative feelings than HC after exclusion. Of note, adolescents with MDD demonstrated stronger INS than HC, indicating the potential empathic stress in depressed adolescents. In addition, there existed altered brain-behavioral association patterns in responses to shared excluded experiences in depressed adolescents. ConclusionsIn summary, our study gives us deeper insights into how a shared psychosocial stressor impacts the INS in depressed adolescents, and it might be demonstrated that INS could be more sensitive than behavioral responses to detect social interaction deficits in depressed adolescents.

neuroscience↗

Progressively reduced cerebral oxygen metabolism and elevated plasma NfL levels in the zQ175DN mouse model of Huntington disease

Huntingtons disease (HD) is a progressive neurodegenerative disorder caused by a CAG-repeat expansion in exon-1 of the huntingtin gene. Currently, no disease-modifying therapies are available, with a significant challenge in evaluating therapeutic efficacy before clinical symptoms emerge. This highlights the need for early biomarkers and intervention strategies. Therefore, it is essential to develop and characterize accurate mouse models and identify early biomarkers for preclinical therapeutic development. In this study, we characterized the pathological progression of the heterozygous zQ175 neo-deleted knock in (zQ175DN) mouse model across four age groups: 3, 6, 10, and 16 months to identify human translatable outcome measures. T2-relaxation-under-spin-tagging (TRUST) MRI was used to assess global CMRO2, while T2-weighted MRI was used to analyze brain volumes. Significant brain volume loss was detected as early as 6 months of age, worsening progressively with age in the zQ175 DN mice, resembling HD brain volumetric changes. A decline in CMRO2 was observed in 6-month-old zQ175 DN mice, with significant and progressive reductions in 10- and 16-months old HD mice. Additionally, PHP1-positive mutant huntingtin (mHTT) aggregates were present in the striatum of zQ175 DN mice at all four age groups, with intranuclear localization prior to 6 months, transitioning to both intranuclear and neuropil aggregates in older zQ175 DN mice, suggesting that the localization of mHTT aggregates may reflect the severity of HD pathogenesis. Interestingly, plasma neurofilament light chain (NfL) protein concentrations were significantly elevated at 6 months of age and older zQ175DN mice. These findings provide valuable insights for selecting outcome measures in preclinical evaluations of HD therapies using the zQ175 DN mouse model.

neuroscience↗

Bidirectional crusher gradient method for estimating the labeling efficiency of pseudo-continuous arterial spin labeling MRI in mice

Pseudo-continuous arterial spin labeling (pCASL) MRI is a widely used imaging technique for studying brain perfusion in health and disease due to its non-invasive and non-contrast nature. Accurate quantification of absolute perfusion values from pCASL signals requires the knowledge of labeling efficiency. However, to date, a reliable technique to measure pCASL labeling efficiency has not been available. In this study, we propose a method using bidirectional crusher gradients to modulate vascular signals in the azygos pericallosal artery (azPA) of the mouse brain, applied with and without pCASL labeling. The combination of corresponding signals allows the estimation of labeling efficiency. Upon systematic testing, optimal acquisition parameters included a labeling duration [≥] 1170 ms, a repetition time of 3 seconds, and an imaging slice thickness of 0.75 mm. In order to quantitatively estimate labeling efficiency, the bolus arrival time to azPA is required and found to be 218.7 +/- 13.3 ms. Typical labeling efficiencies in mouse pCASL scans were 0.780 +/- 0.048 (mean +/- standard deviation). Furthermore, faster arterial flow induced by hypercapnia was found to increase pCASL labeling efficiency. Our method can improve the accuracy of pCASL quantification in mice, offering great potential for advancing its applications in pathophysiological studies.

neuroscience↗