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Chen, C.

Publications and source records attributed to Chen, C..

At least 91 records · Page 5Linked to original sources

Diet-dependent effects of kombucha on the gut microbiome and its neuroactive potential: Associations with reduced anxiety and depressive-like behaviors in mice

Fermented foods are increasingly recognized for their health-boosting potential, yet the mechanisms involved are not fully resolved. Here, we tested whether kombucha reshapes the gastrointestinal microbiome and whether these changes are associated with stress-related behaviors under contrasting dietary backgrounds. Male C57BL/6 mice were fed either a total Western diet (TWD) or a control diet (CTRL) supplemented with kombucha or water three times weekly for seven weeks. Depressive-like and anxiety-related behaviors were evaluated using the forced swimming (FST) and marble burying tests (MBT). Ileum, cecum, and colon microbiomes were profiled via 16S rRNA, ITS2, and shotgun metagenomics, while feces and whole brains were profiled by LC-MS metabolomics. Serum cytokines were measured by ELISA. Results highlight diet-dependent effects of Kombucha on behavioral, microbial and metabolic outcomes. Kombucha reduced immobility in the FST under both diets, whereas fewer marbles buried were observed only under TWD. Kombucha intake enriched Bifidobacterium pseudolongum in the ileum under CTRL and TWD diets, while cecal microbial functions related to amino acid metabolism were stimulated mainly under CTRL. Only CTRL mice receiving kombucha showed higher fecal acetate and butyrate together with lower fecal levels of neurochemically relevant amino acids, including glutamine, phenylalanine, tryptophan, and tyrosine. Under TWD, kombucha was associated with lower spleen weight and altered brain tryptophan/kynurenine profiles. These findings identify kombucha as a food intervention that can remodel gastrointestinal microbial and neuroactive metabolism in a diet depending manner. Associations with reduced depressive and anxiety-related behaviors are promising but warrant further exploration. Key HighlightsO_LIKombucha supplementation reshaped the mice gastrointestinal microbiome and its neuroactive potential C_LIO_LIKombucha intake was associated reduced depressive and anxious like behaviors C_LIO_LIThe potential of kombucha to modulate microbial, metabolic and behavioral outcomes may be dependent on subject dietary background C_LI

microbiology↗

G4 Eurasian avian-like H1N1 swine influenza viruses exhibit enhanced pathogenicity potential in mice and pigs

Currently circulating swine influenza viruses (SIVs) mainly include H1N1, H1N2, and H3N2 subtypes. In this study, two G4 genotype Eurasian avian-like (EA) H1N1 SIVs were isolated from 556 samples collected between 2023 and 2026. A systematic analysis was conducted on the two EA H1N1 isolates (FYD30 and YZF69) to assess their pandemic potential. The hemagglutinin (HA) proteins of both H1N1 viruses possessed residues 225E and 228S, indicating enhanced affinity for human-like -2,6-linked sialic acid receptors, which was confirmed by receptor-binding assays. Polymerase activity tests demonstrated that the two SIVs exhibited significantly higher activity in mammalian cells, relative to avian cells, which is consistent with the efficient replication in mammalian cells. Challenge experiments revealed that both H1N1 caused significant pathogenicity in mice and pigs, with YZF69 exhibited higher virulence than FYD30. The higher virulence of YZF69 may be attributed to its molecular features, including the NP Q357K mutation, and an additional glycosylation site in HA. In conclusion, currently circulating EA H1N1 SIVs have acquired key molecular signatures of mammalian adaptation, exhibit enhanced virulence in mammals, and continue to undergo extensive reassortment driven by international swine trade. These findings highlight the potential pandemic risk of SIVs and underscore the urgent need for strengthened surveillance.

microbiology↗

miR-128 Regulates Hypertensive Vascular Remodeling via PPAR-γ

OBJECTIVEThis study aimed to explore the role and underlying mechanism of microRNA-128 (miR-128) in regulating vascular remodeling in spontaneously hypertensive rats (SHRs), focusing on its targeting of peroxisome proliferator-activated receptor {gamma} (PPAR-{gamma}) and modulation of the Toll-like receptor 4/nuclear factor-{kappa}B (TLR4/NF-{kappa}B) inflammatory pathway. METHODSAll experimental procedures were approved by the Animal Care and Use Committee of Fujian Medical University. In vivo, ten-week-old male SHRs were randomly assigned to three groups: renal denervation (RDN, n=6), sacubitril/valsartan (Sac/Val, n=6), and Sham (n=6). Age-matched Wistar-Kyoto (WKY) rats served as normotensive controls (n=6).Eight weeks after intervention, mesenteric arteries were harvested for histological, functional, and molecular analyses. Serum miR-128 levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The expression levels of key proteins in the vascular wall were assessed via immunofluorescence (IF), immunohistochemistry (IHC), and Western blotting (WB). Bioinformatics analysis and RNA sequencing (RNA-seq) were employed to identify core genes and signaling pathways associated with hypertension-induced pathological inflammation. RESULTSIn vivo, in the SHR sham-operated group, elevated blood pressure, severe vascular remodeling, and impaired vasodilatory function were observed, accompanied by downregulated miR-128 expression and upregulated TLR4/NF-{kappa}B signaling activity (all p < 0.0001).RDN postoperative, miR-128 expression was significantly restored, which in turn inhibited the TLR4/NF-{kappa}B pathway, reduced the production of pro-inflammatory cytokines (including IL-1{beta}, IL-6, and TNF-), and ameliorated vascular dilation dysfunction in SHRs (all p < 0.0001). Mechanistically, miR-128 negatively regulated the TLR4/NF-{kappa}B signaling pathway while upregulating the expression of PPAR-{gamma} (p < 0.05). CONCLUSIONRDN not only exerts a hypotensive effect but also improves hypertensive vascular remodeling. miR-128 inhibits excessive inflammation in vascular smooth muscle cells and alleviates vascular remodeling in SHRs via the PPAR-{gamma}/TLR4/NF-{kappa}B axis. These findings identify miR-128 as a potential therapeutic target for RDN in the treatment of hypertension, providing a novel regulatory strategy for the precision management of cardiovascular diseases.

bioinformatics↗

On the state of protein function prediction: a report on the fourth CAFA challenge

BackgroundThe Critical Assessment of Functional Annotation (CAFA) is a community effort held to understand the field of computational protein function prediction. Every three years, since 2010, the organizers initiate an experiment to collect function predictions on a large set of proteins and then evaluate the performance of predicting methods on a subset of proteins that have accumulated experimental annotations between the submission deadline and the evaluation time. CAFA provides an independent and rigorous assessment of the current state of the art, thus leveling the playing field, highlighting successes, revealing bottlenecks, and offering a forum for the exchange of ideas in protein science. Here, we report the results of the fourth CAFA experiment (CAFA4). ResultsCAFA4 featured the participation of 148 methods from 70 research groups on a total of 46,205 unique proteins over a 5-year annotation accumulation phase, the longest in any CAFA. In a comparison across CAFA2-CAFA4 methods, the prediction of Gene Ontology (GO) terms has clearly improved across all three GO aspects and traditional evaluation settings. While not achieving the first rank, several CAFA2 and CAFA3 methods featured in the top ten methods in many evaluations, suggesting that earlier methods still hold relevance. The performance is weaker in the newly introduced "partial knowledge" evaluation category (proteins with experimental annotations before submission deadline that gained additional annotations in the same GO aspect during the annotation accumulation phase), highlighting the need for a new class of methods. The rankings of the methods were stable over the years in traditional evaluation settings, but less so in the new partial knowledge evaluation. Overall, the field continues to progress with some influx of new participants. Sustained efforts will be necessary to substantially advance it.

bioinformatics↗

Mannosylated nanoparticle immunogens enhance the circumsporozoite protein-specific B cell response and improve protection against sporozoite challenge

Underprocessed oligomannose glycans on protein nanoparticle immunogens engage the innate immune system through mannose-binding lectin and complement, enhancing immunogen trafficking and B cell responses. However, the extent to which oligomannose glycans directly improve protective immunity has remained unclear. Here we generate a series of CSP-bearing I53-50 nanoparticle malaria vaccine candidates with defined numbers and types of engineered N-linked glycans and systematically evaluate their immunogenicity and protective efficacy. Oligomannose display enhanced early plasmablast and germinal center B cell responses, leading to increased CSP-specific memory B cells, long-lived plasma cells, and durable serum antibody titers. Furthermore, nanoparticles bearing oligomannose glycans conferred the strongest protection against sporozoite challenge. By comparing immunogens with defined glycoforms, we attribute improved immune responses and protection specifically to oligomannose rather than complex or truncated glycans. These results will help guide the development of general strategies for glycan engineering aimed at enhancing the protective efficacy of nanoparticle vaccines.

immunology↗

Functional Landscape of Motifs within the Sarbecovirus Spike Cytoplasmic Tail

Sarbecoviruses exhibit extensive diversity in host range and zoonotic potential. Although the ectodomain of the viral spike protein has been well characterized, the functional landscape of the cytoplasmic tail (CT) remains poorly defined. To address this gap, we systematically generated CT truncation variants of representative spike proteins from all major ACE2-utilizing clades to define the roles of conserved host factor-interacting motifs associated with COPI, COPII, FERM, and SNX27. Using vesicular stomatitis virus (VSV)- and lentivirus-based pseudotyping systems, we evaluated viral entry in cells expressing varying levels of ACE2 and TMPRSS2. Our results demonstrate that CT-associated motifs differentially regulate viral infectivity. Specifically, truncation of the COPI- or SNX27-binding motifs markedly reduces entry efficiency, whereas disruption of the COPII-binding motif produces the opposite outcome. By contrast, removal of the FERM-binding motif consistently enhances infectivity across lineages. Mechanistically, truncation of this motif increases spike expression, cell surface localization, incorporation into virions, and particle stability. Importantly, despite these pronounced effects on viral infectivity, deletion of the FERM-binding motif does not affect antigenicity, receptor dependence, or sensitivity to protease inhibitors, as demonstrated by neutralization and inhibition assays. In addition, this approach substantially increases spike protein density on virus-like particles (VLPs). Collectively, by extending the analysis beyond SARS-CoV-1 and SARS-CoV-2, our study reveals a generalizable mechanism in which cytoskeletal anchoring mediated by the FERM-binding motif acts as a limiting determinant of viral assembly. These findings provide a practical framework for optimizing pseudovirus platforms and guiding vaccine development against emerging viral threats.

microbiology↗

Foxp4+ Mandibular Skeletal Stem Cells Orchestrate Bone/Tooth Development and Regeneration

The identity of stem/progenitor cells that drive mandible/tooth development and regeneration remains poorly understood. Here, we show that cranial neural crest-derived Foxp4+ mesenchymal cells condense to form Meckels cartilage, and simultaneously promote mandible development and tooth germ formation. In postnatal mandibles, Foxp4+ cells localize in the endosteum, periosteum and dental pulp, which undergo osteogenesis and odontogenesis under steady state, as well as chondrogenesis during fracture repair. Importantly, transplantation of embryonic or adult Foxp4+CD200+CD105- mandibular skeletal stem cells (mdSSCs) generate ectopic bone and tooth. In contrast, genetic ablation of Foxp4+ cells severely impairs mandible/tooth development and delays fracture healing. Mechanistically, we find that primary cilia critically regulate mdSSC maintenance and differentiation into bone and tooth. FOXP4+PDPN+CADM1+ mdSSCs also exist in adult human mandible, which generate ectopic bone and intact tooth upon transplantation into immunodeficient mice. Taken together, we identify Foxp4+ mdSSCs with potential therapeutic applications in regenerating mandibular bone and tooth.

cell biology↗

Resilience to persistent pain is characterized by stable periodic and increased aperiodic cortical activity

Individual variability in pain perception raises fundamental questions about how biological and experiential factors shape pain processing. Cognitive-demanding motor training is a key driver of use-dependent brain plasticity and may contribute to differences in pain responses. Using musicians as a model of cognitive-motor expertise, we examined how such experience influences cortical dynamics and pain perception during experimentally induced prolonged musculoskeletal pain. Resting-state electroencephalography (EEG) was recorded in musicians and non-musicians before (Day 1) and during pain development (Days 3 and 8) following intramuscular nerve growth factor (NGF) administration. We parameterized periodic (alpha peak frequency, power, frontal asymmetry) and aperiodic (exponent, offset) components of the EEG signal to characterize intrinsic cortical activity. During pain development, non-musicians exhibited slowing of peak alpha frequency, a neural marker associated with ongoing pain. In contrast, musicians showed preserved alpha dynamics and greater left frontal asymmetry, reflecting resilient top-down pain regulation. Musicians also displayed higher aperiodic exponent across sessions, suggesting that musical training shapes the excitation-to-inhibition (E:I) balance potentially reflecting a shift toward greater inhibitory activity. Notably, across all participants, only aperiodic features improved the prediction of pain severity, with higher exponents and higher offsets associated with lower pain ratings. These findings demonstrate that cognitive-motor training shapes cortical dynamics during sustained pain, supporting more stable, resilient cortical responses to pain. Such training also contributes to inter-individual variability in pain processing. Moreover, this study identifies aperiodic EEG components as predictors of pain severity and resilience.

neuroscience↗

Distinct neural architectures of focus: Memory-related engagement is associated with control disengagement

Prevailing models propose that sustained focus is a product of top-down control that amplifies task-relevant representations while suppressing distraction. We challenge this view, demonstrating that the neural signatures of mental focus differ across cognitive modes. In two neuroimaging studies, we used a paradigm that creates conflict between external task goals and self-generated thought and modelled neural activity as a function of trial-by-trial subjective focus to identify how people stay on task in contexts varying in memory engagement. In Study 1, on-task thoughts were associated with distinct neural architectures in arithmetic and comprehension: arithmetic-related focus recruited visual-motor regions, while comprehension-related focus was characterized by the recruitment of memory systems and reduced activation of control regions. Study 2 extended these findings, with both externally directed comprehension and internal memory retrieval associated with a shared neural profile of reduced control engagement, despite reliance on distinct memory systems. Furthermore, focus covaried with activity in heteromodal semantic regions across both reading and listening, suggesting semantic engagement is a primary marker of being on-task during comprehension. Our findings indicate that sustained focus during memory-guided cognition is characterized by mutual disengagement between control and memory networks. This discovery challenges the view that top-down supervision is a universal requirement for task focus, since sustained attention is associated with distinct neural configurations in different cognitive modes.

neuroscience↗

Lipid mobilization establishes metabolic tolerance and prevents autonomic collapse in infection

Survival during infection depends on both pathogen clearance and the ability to tolerate infection-induced physiological changes. Metabolic adaptations are a central component of this tolerance, but the mechanisms underlying these responses remain incompletely defined. Here, we identify white adipose tissue (WAT) lipolysis as a central regulator of metabolic tolerance to infection. In patients with sepsis, higher circulating non-esterified fatty acid (NEFA) levels were associated with reduced mortality. In mouse models of polymicrobial sepsis, infection induced robust adipose lipolysis and increased circulating NEFAs. Genetic ablation of adipose triglyceride lipase (ATGL) in adipose tissue impaired lipolysis, leading to hypothermia, bradycardia, and increased mortality without altering immune cell populations or pathogen burden, consistent with a defect in tolerance rather than resistance. Mechanistically, lipolysis-derived NEFAs, but not glycerol, were required for protection, as restoring circulating NEFAs rescued autonomic stability and survival in adipose tissue ATGL-deficient mice. Infection-induced lipolysis was redundantly regulated and did not depend on any single upstream signaling pathway. Both pharmacologic activation of lipolysis using a {beta}3-adrenergic agonist and exogenous fatty acid supplementation increased circulating NEFAs, improved survival, and promoted tolerance in mice. Consistent with these findings, analysis of real-world electronic health record data demonstrated that septic patients receiving FDA-approved {beta}3-adrenergic agonists had reduced mortality or hospice discharge in a propensity-matched cohort. Together, these results identify WAT lipolysis and circulating fatty acids as key mediators of tolerance to infection and support a therapeutic strategy based on repurposing clinically available {beta}3-adrenergic agonists to improve outcomes in sepsis. One Sentence SummaryWhite adipose tissue lipolysis promotes metabolic tolerance to infection through circulating fatty acids and is associated with improved survival in sepsis

physiology↗

A cinnamyl alcohol dehydrogenase scaffold organizes monoterpenoid indole alkaloid biosynthesis

Biosynthesis of ~3,000 monoterpenoid indole alkaloids (MIAs), including the anticancer drug vinblastine, involves the highly unstable intermediate strictosidine aglycone. Its formation by strictosidine {beta}-glucosidase (SGD) and subsequent conversion by geissoschizine synthase (GS) occur in spatially separated compartments, representing a major biosynthesis bottleneck. Here we discover VinBLAST, a cinnamyl alcohol dehydrogenase-like protein repurposed as a scaffold for efficient processing of this labile intermediate. VinBLAST physically mediates SGD and GS interaction in the nucleus and allosterically enhances GS catalytic efficiency. VinBLAST homologues from diverse plant families enhance biosynthesis of several representative MIAs, with the production of catharanthine increased to ~160 mg L-1 in yeast, nearly 1,000-fold higher than previous studies. Our discovery provides a missing link in organizing MIA biosynthesis and enables scalable bioproduction of geissoschizine-derived therapeutics.

synthetic biology↗

Loss of Mast cells and histaminergic signaling link diet to platelet-mediated NETosis and mammary cancer recurrence

Breast cancer recurrence remains a clinical challenge. The period after the treatment of the primary tumor while cancer cells that evaded initial treatment lay dormant, provides a unique window of opportunity for interventions to prevent recurrence. Specific modifiable factors such as consumption of high fat diets or elevated circulating cholesterol are associated with decreased time to recurrence. Mechanistically, oxidized cholesterol and lipid species have been implicated in the regulation of the tumor microenvironment. This suggests that consumption of food prepared under oxidizing conditions such as pan-frying, may be an underappreciated risk. Using murine models of mammary cancer dormancy, we found that a diet enriched with fat from fried, cured bacon (cfBF) decreased dormancy latency times. Resulting lesions had fewer mast cells (MCs). Loss of MCs alone resulted in reemergence from dormancy. Elevated expression of a MC gene signature in breast tumors was associated with improved progression free and overall survival, highlighting the human relevance of these findings. MCs are a major source of tissue histamine, and lesions from mice fed cfBF had decreased concentrations. Importantly, antagonists of the histamine receptor 2 (H2R) sparked reemergence from dormancy. H2R antagonists are over-the-counter drugs are taken to alleviate gastroesophageal reflux disease. Chronic treatment of mice with H2R-antagonists sensitized platelets towards activation and crosstalk with neutrophils, and subsequent formation of neutrophil extracellular traps (NETs). The loss of platelet or NETosis activity mitigated the H2R-antagonist stimulated reemergence from dormancy. Therefore, we establish a novel metastatic axis which links diet to recurrence via MCs, histaminergic signaling and NETosis: Diet -- MC -- H2R -- (decreased) Platelet Activity -- (decreased) Neutrophil-NETosis -- (decreased) Reemergence from Dormancy. Our data reveal several potential intervention strategies: lifestyle, MC stabilization, histaminergic signaling, and neutrophil and platelet activity.

cancer biology↗

Meningeal neutrophil infiltration drives inflammation-exacerbated pediatric stroke through IL-36γ signaling

Infection and systemic inflammation have been identified as major risk factors for pediatric stroke; however, the immune mechanisms underlying these clinical observations remain poorly understood. Here, we utilized an LPS-sensitized photothrombotic stroke model (LPS/PT) to investigate the contribution of immune cell infiltration to pediatric stroke pathogenesis and identified a previously unrecognized route of neutrophil entry into the injured brain. Compared with photothrombotic stroke alone (PT), LPS/PT mice exhibited markedly increased neutrophil infiltration accompanied by a hyperactivated phenotype. Depletion of neutrophils, but not monocytes, significantly reduced infarct size in LPS/PT animals, indicating a central role for neutrophils in inflammation-exacerbated pediatric stroke. Notably, we observed that neutrophils first accumulated within the leptomeningeal space before entering the brain parenchyma during the early phase of stroke, suggesting that the meninges may serve as an initial staging site for neutrophil recruitment. Using KikGR photoconvertible reporter mice combined with two-photon imaging, we further demonstrated that neutrophils infiltrate the ischemic brain through a compromised meningeal barrier following stroke. Transcriptomic analysis of infiltrating neutrophils revealed distinct gene expression signatures between meningeal neutrophils and circulating blood-derived neutrophils. Among these, IL-36{gamma} was highly enriched in meninges-associated neutrophils during pediatric stroke. Consistently, single-cell RNA sequencing of meningeal immune cells confirmed elevated IL-36{gamma} expression within the neutrophil cluster in LPS/PT animals. Importantly, intracisternal administration of IL-36 receptor antagonist (IL-36Ra) or anti-ICAM-1 antibody significantly reduced infarct volume in this pediatric stroke model. Together, our findings identify the meningeal barrier as a critical gateway for neutrophil infiltration and reveal IL-36{gamma} as a key inflammatory mediator regulating neuroinflammation in pediatric stroke, highlighting a potential therapeutic target for limiting immune-mediated brain injury.

neuroscience↗

Genome-wide DNA supercoiling arises from transcription and SMC activity and mediates transcriptional negative feedback

Genome-wide DNA supercoiling is closely linked to chromatin organization and gene expression, yet the mechanisms establishing genome-scale supercoiling in living cells and its functional consequences remain unclear. Here, we show that genome-wide supercoiling arises from transcription-driven asymmetric topological relaxation together with contributions from SMC complexes in human cells. During RNA polymerase elongation, human topoisomerases preferentially relax positive over negative supercoils, leading to the accumulation of negative supercoiling around genes. This imbalance enriches supercoiling at transcriptionally active regions including TAD boundaries, and promotes the emergence of large-scale topology. In parallel, SMC complexes independently shape genome-wide supercoiling, with cohesin contributing to interphase topology and condensin establishing an overall positively supercoiled mitotic genome. Functionally, the accumulation of transcription-driven negative supercoiling represses local transcription, revealing a supercoiling-mediated negative feedback mechanism. Together, these findings define the mechanistic basis of genome-scale supercoiling in human cells and establish DNA topology as an integral regulatory layer of transcription.

molecular biology↗

Somatic evolution of a cross-reactive germline antibody that expands its breadth to neutralize new SARS-CoV-2 variants

Rapid antigenic drift of the SARS-CoV-2 receptor-binding domain (RBD) underlies immune escape and continues to challenge the durability of antibody-mediated protection. Among the major classes of RBD-directed antibodies, germline-encoded IGHV3-53 responses are highly potent against early SARS-CoV-2 variants but are generally compromised by Omicron-associated mutations. Here, we identify an intrinsically cross-reactive IGHV3-53 germline antibody that recognizes multiple pre-Omicron variants, including SARS-CoV-2 wild-type, Alpha, and Delta. Notably, we demonstrate that targeted somatic evolution can further expand this breadth to overcome the immune escape of different Omicron variants. Guided by integrated structural and sequence analyses, we introduce four somatic mutations (G26E, T28I, S53P, and Y58F) into the germline antibody, resulting in markedly enhanced binding and neutralization of Omicron BA.1, BA.2, and BA.4/5. High-resolution crystal structures reveal that these mutations re-establish critical interactions disrupted by substitutions on Omicron RBD and optimize affinity at a remodeled epitope interface. Collectively, our findings delineate a structural and mechanistic pathway through which an inherently cross-reactive germline antibody lineage can be adaptively refined to counter highly divergent SARS-CoV-2 variants. This work highlights the underappreciated breadth encoded within the naive B-cell repertoire and provides a conceptual framework for engineering and eliciting antibody responses resilient to future antigenic drift.

immunology↗

WTR: A Toolkit for Functional Anterograde Transsynaptic Circuit Mapping

The brain coordinates animal physiology and behavior via neuronal circuits. To understand and simulate brain functions, it is essential to delineate the synaptic connectivity between neurons. Transsynaptic tracers serve as powerful tools for such purposes. In response to the demand for anterograde tracers for circuit mapping and functional interrogation, we developed WTR, a fusion protein of mammalian codon-optimized WGA, TEV-protease cleavage sequence, and Recombinase. WTR expressed via AAV vectors in cell-type-specific starter neurons reaches their postsynaptic neurons and releases Cre/Flpo upon exposure to TEV-protease expressed in downstream neurons. Accompanied by Cre/Flpo-dependent expression of EGFP, GCaMP7s, or ChR2, the toolkit enables labeling, recording, or manipulation of downstream neurons. We utilized WTR to characterize downstream neurons of either glutamatergic or GABAergic neurons in the preoptic area of anterior hypothalamus for their differential actions in thermoregulation or stress responses, respectively. These results establish WTR as a versatile platform for functional anterograde circuit mapping.

neuroscience↗

Multimodal analysis of cell-free DNA identifies epigenetic biomarkers for amyotrophic lateral sclerosis diagnosis and progression

The role of the epigenome in age-related neurodegenerative disorders remains understudied. Here, we analyzed circulating cell-free DNA (cfDNA) from blood to detect methylation changes as a liquid-biopsy for Amyotrophic Lateral Sclerosis (ALS). Our study included 20 patients with sporadic ALS, 10 patients with C9orf72-associated ALS, 10 asymptomatic carriers of the C9orf72 repeat expansion mutation, and 21 non-disease controls. Following targeted enzymatic methyl-sequencing (EM-seq) of [~]4 million CpG sites, we detected numerous differentially methylated genes, including several implicated in ALS disease risk and pathogenesis. By integrating multiple epigenetic features, we delineated a distinct epigenetic signature, which achieved an average area under the curve (AUC) of 0.91 {+/-} 0.10 upon receiver operator characteristic (ROC) analysis, which enabled detection of [~]70% of ALS patients with close to 100% specificity. Furthermore, we also identified a set of genes whose methylation status significantly correlated with clinical disease progression and cerebrospinal fluid (CSF) neurofilament levels. Our results reveal the potential of cfDNA-based biomarkers to accurately diagnose ALS and potentially predict disease progression.

genetics↗

Hepatocyte Embryonic Ectoderm Development (Eed) Deficiency Causes Liver Injury, Fibrosis and Impacts Liver Regeneration

Regeneration depends on tightly coordinated transcriptional programs governed by a dynamic epigenetic landscape to regulate cell identity, proliferation, and tissue remodelling following injury. The liver is highly regenerative due to its ability to rapidly upregulate genes that drive the cell cycle and other genes important for hepatocyte proliferation. In the uninjured liver, many of these genes are poised for activation based on promoter occupancy of trimethylated histone 3 lysine 27 (H3K27me3) and regenerative stimulus provided by partial hepatectomy leads to evacuation of this mark, suggesting this is a key component of proregenerative gene regulation in the liver. H3K27me3 is deposited by the polycomb repressive complex 2 (PRC2). Were we deplete H3K27me3 using hepatocyte specific deletion of key component of PRC2, Embryonic Ectoderm Development (EedHepKO). This results in reduced liver size, increased hepatocyte death, proliferation, and fibrosis associated with upregulation of cell cycle and fibrogenic genes. Though these mice are less likely to survive two-thirds partial hepatectomy than WT (WT) controls, those that do survive increase liver mass faster than WTs. Importantly, genes occupied by H3K27me3 in uninjured WT livers are upregulated in EEDHepKO livers, and become further induced following PH. This demonstrates that PRC2 loss induces liver injury and dysregulates pro-regenerative gene expression, highlighting that epigenetic modulation depends requires precise targeting to achieve enhanced regenerative

pathology↗