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Li, Z.

Publications and source records attributed to Li, Z..

At least 343 records · Page 19Linked to original sources

AniMarkerDB: a comprehensive database for exploring cell types and marker genes in livestock and poultry at single-cell resolution

Single-cell RNA sequencing (scRNA-seq) has dramatically advanced the understanding of cellular heterogeneity. While numerous marker gene databases are available for humans and mice, a lack of systematic resources for livestock and poultry species remains, limiting progress in functional genomics, immunology, and breeding.. To address this challenge, we developed AniMarkerDB (https://animarkerdb.bio), a comprehensive and curated database dedicated to marker genes and immune-related epitopes in economically animals, including chicken, pig, and duck. AniMarkerDB integrates 7,010 marker gene across 37 tissues and 846 cell types, together with 71,442 immune epitope records from IEDB. All entries undergo rigorous literature curation, manual validation, and multi-level quality control, with standardized nomenclature and annotation to ensure data consistency and reusability. The platform supports flexible queries by species, tissue, cell type, or gene. It offers analytical tools for cross-species comparison model organisms such as human and mouse, interactive single-cell atlas visualization, and user-defined cell type annotation. Additionally, AniMarkerDB provides dynamic visualizations and export options, enabling researchers to efficiently obtain large-scale marker and epitope data for downstream applications such as infectious disease research, vaccine target design, and comparative immunology. Looking ahead, AniMarkerDB will expand species coverage and incorporate additional modalities, including single-cell atlases from healthy and disease models, establishing itself as a comprehensive and authoritative platform for animal cell biology, disease modeling, and translational research. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=136 SRC="FIGDIR/small/682327v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@af7e7borg.highwire.dtl.DTLVardef@198d114org.highwire.dtl.DTLVardef@1c69ed2org.highwire.dtl.DTLVardef@e4fc43_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

Propionate metabolism dysregulation promotes drug-tolerant persister cell survival in non-small cell lung cancer

Recent studies show that genetic sequencing can not fully explain drug resistance in non-small cell lung cancer (NSCLC), suggesting undiscovered non-genetic mechanisms that can enable cancer cell survival. Propionate metabolism is the pathway by which odd-chain fatty acids, branched chain amino acids, and cholesterol are metabolized. We have previously shown that methylmalonic acid (MMA), a byproduct of propionate metabolism that accumulates when the pathway is disrupted, can activate epithelial-to-mesenchymal transition (EMT) in cell lines. But the clinical significance of propionate metabolism in cancer patients is not known. Here we show, for the first time, that propionate metabolism is dysregulated in patients with non-small cell lung cancer. MMA is elevated in lung tumors and in the serum of patients with metastatic NSCLC. Metabolism of cobalamin associated B (MMAB), a key regulatory gene of propionate metabolism, is downregulated in NSCLC and drug-tolerant persister cells, leading to MMA accumulation and EMT activation. We show that restoring expression of MMAB in NSCLC enhances targeted therapy and suppresses TGFB signaling. These findings reveal propionate metabolism dysregulation as a non-genetic mechanism of drug resistance and highlight propionate metabolism as a potential therapeutic target.

cancer biology↗

Phosphoproteomics uncovers rapid and specific transition from plant two-component system signaling to Ser/Thr phosphorylation by the intracellular redox sensor AHK5

The Arabidopsis thaliana histidine kinase 5 (AHK5) is proposed to function as a intracellular sensor of active oxygen species (ROS) and redox conditions, fine-tuning responses to diverse ROS-inducing stimuli through a multistep phosphorelay (MSP) system. To elucidate the mechanism of ROS perception by AHK5 and signaling through posttranslational modifications, a comparative phosphoproteomics analysis was conducted using ahk5 loss-of-function and wild type seedlings in response to exogenously applied H2O2. Under control and H2O2-related conditions, a rapid signaling transition from the MSP to Ser/Thr phosphorylation was observed. AHK5 appears to regulate ROS-responsive phosphorylation at the plasma membrane by the modification of nanodomain components such as remorins, aquaporins, IQDs, and patellins, positioning it as a central integrator of redox signaling during adaptation to diverse stresses. AHK5 drives a distinct, ABA-independent signaling pathway for H2O2-induced stomatal closure, likely by regulating phosphorylation of key components such as RBOHD, CAS, and HPCA1. Moreover, AHK5-fine-tuned root development involves ABA-dependent signaling and appears to act through modulation of auxin transport via phosphorylation of auxin carrier, highlighting a mechanistic divergence between ROS responses in the shoot and root. Our data further suggest that AHK5 orchestrates stress-responsive nanodomain-associated signaling hubs through regulation of membrane trafficking, cytoskeletal dynamics, and endocytosis to mediate stress responses. HighlightAHK5 perceives and may amplify H2O2 signaling by linking two-component systems to Ser/Thr phosphorylation, likely by modulating membrane-associated signalosomes, thereby fine-tuning responses to stress-induced reactive oxygen species.

plant biology↗

Imaging Cellular Metabolic Rewiring with SuMMIT-SRS

Cells dynamically rewire their metabolic pathways in response to physiological and pathological cues. Such plasticity is particularly critical in neurons, stem cells, cancer cells, and immune cells, where biosynthetic demands can shift rapidly. However, current metabolic imaging techniques using isotope labeling typically track only one metabolite at a time, limiting their ability to capture the rapid dynamics of complex metabolic networks including coordinated precursor utilization, crosstalk, and turnover. Here, we present Subcellular Multiplexed Metabolic Isotope Tracing Stimulated Raman Scattering microscopy (SuMMIT-SRS), a platform that enables simultaneous visualization of multiple metabolic dynamics at subcellular resolution. By exploiting the distinct vibrational signatures of carbon-deuterium bonds derived from multiple deuterated amino acids, lipids, and monosaccharide tracers, SuMMIT-SRS maps co-regulated DNA, RNA, protein, and lipid synthesis at the same time and resolves various individual amino acid-mediated metabolic pathways within intact cells and tissues. We demonstrate SuMMITs broad utility across Drosophila fat body tissue and developing brain, tumor organoids, aged human neurons, and mouse liver, capturing cell type-specific metabolic rewiring under genetic and pathological perturbations. This approach extends SRS to multiplexed isotope tracing, offering a powerful tool to uncover dynamic and complex biosynthesis programs in development, health, and disease.

bioengineering↗

Agro-STARR-seq enables in planta genome-wide enhancer discovery and AI-empowerd enhancer design

Comprehensive enhancer screening is essential for dissecting gene regulatory networks. However, methods for such screening remain limited in plants. We present Agro-STARR-seq, an in planta enhancer screening platform using Agrobacterium-mediated delivery of STARR-seq libraries into Nicotiana benthamiana leaves. In the Arabidopsis genome, we identified 14,715 sequences with enhancer activity, of which 91.59% were located outside of open chromatin regions. This largest in planta enhancer dataset to date enabled AI-assisted design of highly active synthetic enhancers. For the large N. benthamiana genome, we pre-processed the genomic DNA with an Assay for Transposase Accessible Chromatin (ATAC) procedure before the Agro-STARR-seq protocol,and found that only one-third of open chromatin exhibited enhancer activity, 76.00% of which showed no canonical H3K27ac histone marks. Footprinting analysis further enables systematic linkage of transcription factor (TF) binding to enhancer function. Overall, Agro-STARR-seq provides a novel platform for dissecting and engineering plant enhancers.

genomics↗

A Genome-Based Pipeline for Digital Siderophore Typing in Pseudomonas Iron-Interaction Network

Siderophores are key mediators of microbial interactions, especially in iron-limited environments. While traditional experimental methods for siderophore typing are time-consuming and low-throughput, we present a genome-based pipeline for high-throughput digital siderophore typing in Pseudomonas. Our approach integrates profile Hidden Markov Models (pHMMs), substrate-specific motif identification, and co-evolutionary analysis to predict both the structure of pyoverdines and their corresponding uptake receptors from any given Pseudomonas genome. By this approach, we developed pHMM from 94 previously defined receptor groups and validated their accuracy and robustness across 14,230 Pseudomonas genomes. Application of our method to this large dataset demonstrated the potential of our algorithm for identifying both novel "lock-key" receptor groups and previously uncharacterized pyoverdine structures. Notably, our pipeline corrected long-term misclassifications in classical strains and proposed a new reference for the canonical Group III pyoverdine. Furthermore, interaction network analysis supports the observation of distinct siderophore utilization patterns between pathogenic and non-pathogenic strains. This standardized, user-friendly platform offers a robust tool for annotating siderophore behaviors in Pseudomonas and demonstrates the potential of digital siderophore typing in exploring iron-mediated ecology across microbes. Impact statementIron is vital for microbes. In most environments, they secrete diverse siderophores to scavenge iron. The types of siderophores a strain produces and uptakes shape its interactions, from cooperation to cheating and competition; characterizing this is called "siderophore typing." While traditional methods are limited by experimental capacities, our genome-based digital pipeline revolutionizes the process by predicting siderophore structures and receptor types directly from genomes, enabling large-scale analysis of 14,230 Pseudomonas strains. The results reveal novel groups, correct historical misclassifications, and link patterns to pathogenicity, providing a standardized software for ecological studies, antibiotic design, and bioremediation.

microbiology↗

Multilayer control of KaiR1D-autoreceptor function by the auxiliary protein Neto

Kainate-type glutamate receptors and their dedicated auxiliary protein Neto function at both pre- and postsynaptic sites to regulate the activity of synaptic networks. However, attributing specific synaptic functions to Neto and/or kainate receptors is challenging. Here we focus on Drosophila KaiR1D receptors, which modulate synaptic transmission at neuromuscular junction, and elucidate the role of Neto in the regulation of autoreceptor activities and neurotransmitter release. We show that Neto- limits the presynaptic accumulation and function of KaiR1D autoreceptors in vivo. Using outside-out patch recordings, we demonstrate that Neto- modulates the KaiR1D gating properties, slowing desensitization and attenuating the block by intracellular polyamines and extracellular toxins. Neto- also promotes the axonal distribution of KaiR1D, but this function is not critical for the KaiR1D-dependent regulation of synaptic transmission. Instead, Neto- increases the charge transfer and likely the KaiR1D-mediated influx of Ca2+ in the presynaptic compartment leading to increased neurotransmitter release. Our data demonstrate that Neto- provides multiple layers of modulation to KaiR1D autoreceptors to ensure proper neurotransmitter release. These findings broaden our view on how auxiliary subunits shape channel gating and subcellular distribution, suggesting that coordinated regulation of receptor function and localization represents an ancestral strategy to safeguard synaptic stability.

neuroscience↗

Quantitative Multicolored Deep Imaging of Human Bones Reveals a Composite Osteo-Sinusoidal Niche for Mesenchymal Stromal Cells.

Human bone marrow mesenchymal stromal/stem cells (BM-MSCs) are widely utilized in clinical trials and tissue engineering; however, their native microenvironment remains poorly understood. Here, we introduced a tissue-clearing protocol for human bones and integrated it with simultaneous mRNA and protein detection. Using this protocol, named DeepBone, we spatially mapped BM-MSCs relative to key bone microenvironment components, including human blood capillaries, adipocytes, sinusoids, and bony trabeculae. Quantitative analysis revealed that the native microenvironment of human BM-MSCs in young bone is enriched in vasculature, sinusoids, bone matrix, and adipocytes. In contrast, in aged bone, BM-MSCs showed no preferential association with bone or adipocytes. Proliferative BM-MSCs were predominantly found along blood vessels. Moreover, we identified a specialized microenvironment for BM-MCs in young bone, characterized by sinusoids coiled around trabeculae and enriched by R-type vessels. These findings provide novel insights into the native niches of BM-MSCs, offering a foundation for the development of tissue-engineering strategies that mimic their physiological context.

cell biology↗

Functional interrogation uncovers a critical role for a high-plasticity cell state in lung adenocarcinoma

Plasticity--the ability of cells to undergo phenotypic transitions--drives cancer progression and therapy resistance1-3. To date, strategies targeting cancer plasticity have not advanced to the clinic due to a lack of fundamental understanding of the underlying mechanisms. Recent studies have suggested that plasticity in solid tumors is concentrated in a minority subset of cancer cells4-6, yet functional studies interrogating this high plasticity cell state (HPCS) in situ are lacking. Here, we developed mouse models enabling detection, longitudinal lineage tracing, and ablation of the HPCS in autochthonous lung tumors in vivo. Using lineage tracing, we uncover the HPCS cells are dedifferentiated but possess high capacity for cell state transitions, giving rise to both early neoplastic (differentiated) and advanced lung cancer cell states in situ. Longitudinal lineage tracing using secreted luciferases reveals HPCS-derived cells harbor high capacity for growth when compared to bulk cancer cells or another defined cancer cell state with features of differentiated lung epithelium. Suicide gene-mediated ablation of the HPCS in early neoplasias abrogates tumor progression. Ablating HPCS cells in established tumors by suicide gene or HPCS-directed CAR T cells robustly reduces tumor burden, whereas ablation of a differentiated lung cancer cell state had no effect. We further demonstrate that the HPCS gives rise to therapy-resistant cell states, whereas ablation of the HPCS abrogates resistance to chemotherapy and oncoprotein-targeted therapy. Interestingly, an HPCS-like state is ubiquitous in regenerating epithelia and in carcinomas of multiple other tissues, revealing a convergence of plasticity programs. Our work establishes the HPCS as a critical hub enabling reciprocal transitions between cancer cell states, including acquisition of states adapted to cancer therapies. Targeting the HPCS in lung cancer and in other carcinomas may suppress cancer progression and eradicate treatment resistance.

cancer biology↗

Site-specific genome engineering of primary human natural killer cells for programmable anti-tumor function

Natural killer (NK) cells are emerging as a promising platform for engineered adoptive cell therapies. However, gene editing in NK cells remains challenging, and more effective strategies are needed. Here, we established a robust, feeder-free, and modular workflow for genome engineering in primary human NK cells, combining CRISPR/Cas9 with AAV6-mediated transgene delivery. Efficient site-specific transgene integration was achieved at various loci and can be coupled with concurrent disruption of the target locus in a single editing step. Furthermore, transgene expression was tunable according to the integration site and promoter. We applied this strategy to target a chimeric antigen receptor (CAR) transgene to a panel of inhibitory NK receptor loci, establishing a synergistic approach to enhance anti-tumor activity and facilitate the reliable comparison of CAR variants without expression bias. We identified TIGIT as an ideal locus that supports strong CAR expression and anti-tumor function. This genome engineering framework, which leverages multiple, complementary and precisely controlled genetic edits, can support the rational design of future NK-cell therapies tailored to overcome cell-intrinsic limitations and tumor-specific barriers.

immunology↗

Base-editing a single missense mutation in A20 enhances CAR-T cell efficacy

T cell exhaustion limits the efficacy of cancer immunotherapies. Here, we performed genome-wide loss-of-function screening in repetitively stimulated human T cells and identified the mulitfunctional ubiquitin-modifying protein A20/TNFAIP3 as a major negative regulator of exhausted T cell persistence. Protein large language modeling, deep base-editing mutagenesis, and studies in immunocompetent mice with domain-specific inactivating mutations revealed A20s non-enzymatic M1 ubiquitin-binding zinc finger 7 (A20ZF7) motif as critical to suppression of anti-tumor immunity. A20ZF7-deficient CD8+ tumor-infiltrating lymphocytes (TILs) resisted terminal exhaustion and circumvented an unappreciated mechanism restraining perforin degranulation in terminally exhausted cells. Human chimeric antigen receptor (CAR)-T cells engineered via base-editing to inactivate A20ZF7 via a single missense mutation also resisted exhaustion, secreted more perforin and robustly suppressed cancer in vivo. These studies pinpoint A20ZF7 as a novel T cell checkpoint and reveal precision base-editing of missense mutations as an effective approach to enhance CAR-T cell therapy.

immunology↗

JMJD1B-mediated FEN1 demethylation allows timely switching of Okazaki fragment maturation core enzymes to avoid mutagenic flap ligation by PARP1-LIG3

Efficient and faithful Okazaki fragment maturation (OFM) depends on the PCNA-coordinated actions of core enzymes Pol{delta}, FEN1, and LIG1. We demonstrate that Pol{delta}, FEN1, and LIG1 sequentially but not simultaneously bind to PCNA in mammalian cells. The association of FEN1 with PCNA, which lies at the center of this orderly program, is mediated by FEN1 R192 methylation, which is also crucial for preventing premature loading of LIG1. Conversely, FEN1 demethylation by the recently identified arginine demethylase JMJD1B promotes FEN1 dissociation from PCNA and LIG1 recruitment. Disruption of the sequential PCNA binding program in R192Q or Jmjd1b-/- cells results in unprocessed 5 flaps that prevent OFM and induction of PARP1-dependent recruitment of LIG3, which has flap ligation activity to join incompletely processed OFs. This alternative OFM process supports cell survival but causes duplications and other DNA mutations. Our findings define fundamental and alternative DNA replication processes underlying mutagenesis and cell survival. HighlightsO_LIThe core enzymes involved in Okazaki fragment maturation (OFM), DNA polymerase {delta} (Pol{delta}), flap endonuclease 1 (FEN1), and ligase 1 (LIG1), sequentially bind to the scaffold protein PCNA for their concerted actions C_LIO_LIFEN1 R192 methylation enables FEN1 binding to PCNA; JMJD1B-mediated FEN1 arginine demethylation provokes FEN1 exit from PCNA and LIG1 recruitment C_LIO_LIFEN1 R192Q mutation and JMJD1B deficiency oppositely alter dynamic PCNA interactions with FEN1 and LIG1 and result in distinct OFM DNA intermediate structures C_LIO_LIActivation of PARP1 at replication forks due to disruption of the sequential PCNA binding program induces LIG3-mediated alternative mutagenic 5 flap ligation for survival. C_LI

cell biology↗

Macrophages display spatiotemporal specificity in intrahepatic cholangiocarcinoma and drive tumour progression via OSM and THBS1

Tumor-associated macrophages (TAMs) are abundant in intrahepatic cholangiocarcinoma (ICC) and correlate with poor prognosis, but their non-immunosuppressive roles remain unclear. This study aimed to define TAM transcriptional heterogeneity and map their interactions with ICC cells that promote malignancy beyond immune suppression. Single-cell and spatial transcriptome analysis with mouse and human ICC tissues revealed a TAM subpopulation, designated M{varphi}_VEGFA, that emerged as the major macrophage population from the intermediate stage of ICC development onward. Data from Gene Expression Omnibus (GEO) and spatial transcriptome indicate that M{varphi}_VEGFA was associated with poor prognosis and spatially localized to the ICC cells. Cell co-culture and cell-cell communication analyses revealed that M{varphi}_VEGFA promoted ICC cell proliferation via secreted OSM and downstream OSMR-STAT3-CCND1 axis, and enhanced ICC cell invasion through THBS1 and downstream CD47-mTOR/DBN1 signaling. Critically, multiplex immunofluorescence with human ICC tissue microarray indicated that OSM and THBS1 were co-elevated in human ICCs, and dual blockade of both targets inhibited ICC progression in mouse models. This study uncovers the direct and critical roles of M{varphi}_VEGFA in driving ICC progression with paracrine signaling and further highlights the potential of targeting macrophages in ICC treatment.

cancer biology↗

Absolute hand determination of glycofibrils from natural sources in cryo-EM

Glycans are one of the four fundamental macromolecules that constitute life. However, compared with proteins and nucleic acids, our understanding of the structures and functional mechanisms of glycans remains limited. Moreover, it is generally challenging to obtain high-resolution three-dimensional structures of glycans. Recent studies have demonstrated the potential of the CryoSeek strategy in enabling high-throughput structural determination of glycans, thereby presenting novel avenues for their structural investigation. Meanwhhile, unlike proteins, near atomic resolution density maps of glycofibrils do not inherently facilitate the determination of absolute hand, which is a prerequisite for building atomic models of glycofibrils. Existing absolute hand determination methods have severe limitations in the cases of glycofibrils from natural sources. In this study, we introduce Ahaha, a straightforward and efficient method for determining such absolute hand in cryo-EM. With their absolute hand measured by Ahaha, we built atomic models of four glycofibrils derived from a natural water sample, facilitating the study of glycans. The online service of Ahaha is available at https://cryoseek.org/ahaha.

biophysics↗

A Pangenomic Method for Establishing a Somatic Variant Detection Resource in HapMap Mixtures

Somatic mosaicism is essential in human biology and disease, yet robust benchmarks are scarce. The SMaHT Consortium mixed six HapMap cell lines to create artificial somatic variants spanning 0.25% to 16.5% variant allele fractions. We developed a technology-agnostic method that builds pangenome graphs from individual assemblies to create unified benchmarking sets: > 6M single-nucleotide variants, 1.8M small insertions/deletions, 49K structural variations, and 10K mobile element insertions across autosomes, X, and mitochondrial chromosomes. We validated the variants using ultra-deep simulated reads and developed a binomial-based model to estimate coverage requirements for variant detection. Evaluating multiple callers showed CHM13 alignment improves structural variant detection and offers advantages in difficult-to-map regions compared to GRCh38. Systematic characterization showed regions with low detection rate are enriched in centromeres, satellite sequences, tandem repeats, and falsely duplicated genes. This accurate, versatile resource enables systematic evaluation of somatic variant detection technologies.

genomics↗

CryoSeek identification of glycofibrils with diverse compositions and structural assemblies

Last year, we reported CryoSeek, a research strategy that employs cryo-electron microscopy (cryo-EM) to discover novel bio-entities from any accessible source, supplemented with AI-facilitated data processing and bioinformatic analyses. Here we report CryoSeek characterization of five additional glycofibrils isolated from the Tsinghua Lotus Pond (TLP), named TLP-IPT, TLP-12, TLP-3, TLP-2, and TLP-0, with overall resolutions ranging from 3.0-3.5 [A]. These five glycofibrils, all covered with dense glycoshells, have decreasing ratios of the central protein components, with TLP-0 with no protein at all. IPT (immunoglobulin-like, plexins, transcription factors) refers to the tandem domain that constitutes the central filament of this type of glycofibrils. In TLP-12, the central cylindrical stem is made of a trimer of dodecapeptide repeats that weave to {beta}-sheet ribbons. The central stem of TLP-3 is also a trimer, but of linear tripeptide repeats. TLP-2, similar to our previously reported TLP-4, only has a linear chain of dipeptide repeats, and glycosylation occurs to a phosphoserine in each repeat. Glycan-mediated interactions are essential for the assembly of all five glycofibrils. Our previous and present studies demonstrate the diversity in the high-order structure and folding of glycans.

biophysics↗

Lifespan Trajectories of Asymmetry in White Matter Tracts

Asymmetry in white matter is believed to give rise to the brains capacity for specialized processing and is involved in the lateralization of various cognitive processes, such as language and visuo-spatial reasoning. Although studies of white matter asymmetry have been previously documented, they have often been constrained by limited age ranges, sample sizes, or the scope of the tracts and structural features examined. While normative lifespan charts for brain structures are emerging, comprehensive charts detailing white matter asymmetries across numerous pathways and diverse structural measures have been notably absent. This study addresses this gap by leveraging a large-scale dataset of 35,120 typically developing and aging individuals, ranging from 0 to 100 years of age, from 50 primary neuroimaging studies. We generated comprehensive lifespan trajectories for 30 lateralized association and projection white matter tracts, examining 6 distinct microstructural and macrostructural features of these pathways. Our findings reveal that: (1) asymmetries are widespread across the brains white matter and are present in all 30 pathways; (2) for a given pathway, the degree and direction of asymmetry differ between features of tissue microstructure and pathway macrostructure; (3) asymmetries vary across and within pathway types (association and projection tracts); and (4) these asymmetries are not static, following unique trajectories across the lifespan, with distinct changes during development, and a general trend of becoming more asymmetric with increasing age (particularly in later adulthood) across pathways. This study represents the most extensive characterization of white matter asymmetry across the lifespan to date, charting how lateralization patterns emerge, mature, and change throughout life. It provides a foundational resource for understanding the principles of white matter organization from early to late life, its relation to functional specialization and inter-individual variability, and offers a key reference for interpreting deviations during healthy development and aging as well as those associated with clinical populations.

neuroscience↗

Low Dose GLP-1 Therapy Attenuates Pathological Cardiac and Hepatic Remodelling in HFpEF Independent of Weight Loss

BACKGROUND AND AIMSHeart failure with preserved ejection fraction (HFpEF) remains a therapeutic challenge. GLP-1 receptor agonists (GLP-1RAs) show clinical promise, and the prevailing hypothesis is that their benefits are primarily driven by weight loss and the downstream benefits of improved functional status. We investigated the weight loss-independent effects of low-dose GLP-1RA therapy in a clinically relevant rodent model of severe cardiometabolic HFpEF. METHODSTen-week-old male ZSF1 obese rats with spontaneous HFpEF were treated with low-dose semaglutide (30 nmol/kg twice weekly, n=6) or vehicle for 16 weeks. Comprehensive assessments included body weight, 2-D echocardiography, invasive hemodynamics, exercise capacity as well as cardiac and hepatic fibrosis and lipid deposition. The study utilized advanced multi-omics approaches, including single-cell RNA sequencing of the heart and liver, as well as cardiac, hepatic and plasma proteomics, to explore underlying mechanisms. RESULTSIn ZSF1 obese rats, low-dose semaglutide in the absence of weight loss, significantly improved cardiac function, exercise tolerance, and attenuated fibrosis in the heart and liver. Interestingly, semaglutide therapy reduced cardiac and hepatic lipid content as well as lipid droplets in cardiac myocytes and hepatocytes. Mechanistically, multi-omics analyses of cardiac and hepatic tissues revealed that semaglutide exerted these benefits by improving cardiac metabolism, interfering with pro-fibrotic and pro-hypertrophic signals, and by reducing systemic inflammation. CONCLUSIONSLow-dose semaglutide provides significant cardioprotective, hepatoprotective, and metabolic benefits in HFpEF independent of weight loss. Our findings support the investigation of lower GLP-1RA dosing in HFpEF and other cardiovascular conditions, including in non-obese patients, to expand the clinical utility of these potent drugs. Translational PerspectiveWe demonstrate that low-dose semaglutide attenuates HFpEF-mediated pathological cardiac and hepatic remodelling in HFpEF independently of the weight loss effects of GLP-1 receptor activation. Primary mechanisms are attenuated cardiac and hepatic fibrosis and reverse lipid transport. These findings provide a mechanistic basis for the direct cardiovascular actions of GLP-1RAs, revealing their potential to modulate key disease drivers like fibrosis and lipotoxicity. These data support the use of lower, better-tolerated doses of GLP-1RAs to treat HFpEF, potentially benefiting a wider range of patients, including those who are not obese or who suffer from side effects with current GLP-1 regimens.

pharmacology and toxicology↗