JHEP Reports

Background & AimsHepatitis B virus (HBV) drives hepatocellular carcinoma in part through the activity of its X protein (HBx), yet the mechanisms by which HBx alters hepatocyte function remain incompletely understood. Progress has been limited by the lack of relevant human models that support controlled HBx expression in mature hepatocytes. Here, we use an improved hepatocyte-like organoid (HLO) platform that supports enhanced hepatocyte maturation to investigate HBx function in a differentiated hepatocyte context. MethodsAdult stem cell-derived HLOs were differentiated using an optimized protocol to generate hepatocyte-like cells with enhanced maturation and transcriptional similarity to primary liver tissue. HBx function was interrogated using both cognate promoter-driven expression and doxycycline-inducible systems across multiple donor-derived organoid lines. Transcriptomic, pathway, and single-cell imaging analyses were performed to assess the impact of HBx expression on hepatocytes. ResultsHBx expression consistently suppressed apoptosis-associated transcripts and reduced expression of core hepatocyte identity genes, including CYP3A4. Pathway analysis revealed downregulation of liver-specific functions, including metabolism, detoxification, complement, and coagulation. At the single-cell level, higher HBx expression was associated with reduced caspase 3/7 activation following apoptotic challenge and decreased hepatocyte marker expression. Functionally, HBx expression increased resistance to apoptosis and enhanced the ability of differentiated hepatocyte-like cells to revert to a proliferative, less differentiated state. ConclusionsHBx expression in differentiated human liver organoids reduces apoptosis and impairs hepatocyte identity, consistently across donors and expression systems. These findings support a model in which HBx promotes a survival-permissive less differentiated state that may contribute to early HBV-driven tumorigenesis. This HLO platform provides a relevant system to dissect HBV-host interactions and reveals a mechanism by which HBV may prime the liver for malignant transformation. Impact and implicationsUnderstanding how HBV promotes hepatocellular carcinoma remains a critical challenge, partly due to the lack of physiologically relevant human derived model systems to study HBx function. Using a differentiated adult human liver organoid system, we show that HBx simultaneously suppresses apoptosis and disrupts hepatocyte identity, providing a mechanistic framework for how HBV may prime hepatocytes for malignant transformation. These findings are particularly relevant for researchers studying HBV pathogenesis and liver cancer, as well as for clinicians aiming to better understand early disease progression. While further validation in more complex multicellular systems is needed, this platform can support the identification of HBx-targeted therapeutic strategies and guide the development of improved adult human derived models for virus-host interaction studies.

Purpose Metabolic dysfunction-associated steatotic liver disease (MASLD) is a major cause of chronic liver disease and liver-related morbidity worldwide. Although dietary factors may influence MASLD progression, the long-term liver-specific implications of artificially sweetened beverage (ASB) intake remain unclear. We aimed to examine the association between ASB intake and the risk of liver-related adverse events and liver-related death among individuals with MASLD. Methods This prospective cohort study included 50,562 participants with MASLD from the UK Biobank. ASB intake was assessed using 24-hour dietary recalls and categorized as 0, >0-1, and >1 serving/day. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for liver-related adverse events and liver-related death. Restricted cubic spline models were used to assess dose-response patterns, and competing-risk analyses were performed by treating liver-related death as a competing event for liver-related adverse events. Additional substitution, subgroup and sensitivity analyses were conducted to evaluate the robustness of the findings. Results During a median follow-up of 12.8 years, 292 liver-related adverse events and 91 liver-related deaths occurred. Compared with participants reporting no ASB intake, those consuming >1 serving/day had a higher risk of liver-related adverse events in the fully adjusted model (HR 1.40, 95% CI 1.02-1.93; P = 0.039), whereas the association for >0-1 serving/day was not statistically significant (HR 1.26, 95% CI 0.92-1.71; P = 0.149). The risk of liver-related adverse events increased across ASB intake categories (P for trend = 0.023). Restricted cubic spline analysis indicated a positive linear association between ASB intake and liver-related adverse events (P-overall <0.001; P-nonlinearity = 0.72). In competing-risk analysis, the association for >1 serving/day remained consistent after accounting for liver-related death as a competing event (sub-HR 1.40, 95% CI 1.02-1.93; P = 0.038; Gray test P = 0.006). The association was robust in sensitivity analyses. ASB intake was not significantly associated with liver-related death, and beverage substitution analyses showed no significant associations. Conclusion Among individuals with MASLD, high ASB intake, particularly >1 serving/day, was associated with an increased risk of liver-related adverse events, but not liver-related death. This association was consistent across dose-response, competing-risk, and sensitivity analyses, suggesting that high ASB intake may represent a potential dietary risk marker for adverse liver outcomes in MASLD.

miRNA-based transcriptomic analysis of extracellular vesicles (EVs) provide a promising strategy for identifying non-invasive biomarkers and understanding complex pathological mechanisms. Recently, however, urinary extracellular vesicles (uEVs) have emerged as a valuable window into molecular alterations. Despite the high morbidity and mortality associated with alcohol use disorder (AUD), the molecular mechanisms underlying its sex-specific differences remain poorly understood. To address this, we characterize for the first time the uEV miRNome in AUD, revealing its sexually dimorphic profile. We employed uEVs from actively drinking AUD patients of both sexes who did not have advanced liver disease, alongside matched controls. Deep sequencing revealed 14 differentially expressed miRNAs in females (e.g., hsa-miR-197-3p, hsa-miR-19b-3p, hsa-miR-505-3p, hsa-miR-625-5p, and hsa-miR-27a-5p) and 6 in males (e.g., hsa-miR-1290, hsa-miR-1246, hsa-miR-450a-5p, and miR-590-5p). Notably, whereas hsa-miR-4787-5p was consistently overexpressed in uEVs from both sexes, it was absent in plasma-derived EVs, highlighting the specificity of the urinary compartment. Remarkably, the miRNA signatures we uncovered reflect the multiorgan impact of AUD. For instance, hsa-miR-1290 and hsa-miR-197-3p point to alcohol-related liver injury and systemic inflammation, whereas hsa-miR-19b-3p and hsa-miR-1246 signal neuroinflammation and neuronal stress. A subset, including hsa-miR-1290, hsa-miR-1246, and hsa-miR-27a-5p, has been implicated in cancer contexts. Collectively, these findings support the uEV miRNome as a promising sex-informed molecular signature of AUD with biomarker and mechanistic relevance.

Overnutrition-related liver dysfunction and cancer are increasingly prevalent and highly resistant to immunotherapy. While metabolic dysregulation is a hallmark of hepatocellular carcinoma (HCC), how nutrient overload impairs antitumor immunity remains unclear. Here, we show that short-term Western diet (WD) exposure drives near-complete loss of CD8 T cell infiltration and antitumor function in HCC. We identify dietary linoleic acid (LA), the most abundant {omega}-6 fatty acid, as the dominant immunosuppressive driver. Cancer cell-restricted FADS2-mediated desaturation of LA to longer-chain {omega}-6 PUFAs drives their accumulation in the tumor interstitial fluid, suppressing infiltrating CD8 T cells via lipid peroxidation. FADS2 inhibition restores CD8 T cell function and sensitizes WD-driven HCC to PD-1-based immunotherapy. Further, the Parkinsons disease-associated deglycase DJ-1 protects LA-handling proteins from methylglyoxal-mediated glycation, sustaining tumoral immunosuppressive PUFA production. Across multiple independent human MASLD-HCC cohorts, LA metabolic activity correlates with CD8 T cell impairment, immune exclusion, and immunotherapy resistance. Overall, these studies identify a dietary lipid axis as a therapeutically actionable vulnerability in WD-associated HCC.

Autoimmune hepatitis (AIH) is a chronic progressive liver disease that despite suggestive serum autoantibodies or plasma cell enrichment, remains functionally a diagnosis of exclusion. Whether the broader cellular composition of the liver might enable improved specificity of diagnosis has not been systematically tested. We prospectively recruited patients undergoing a clinically-indicated liver biopsy for suspected AIH and performed single-nucleus RNA sequencing (snRNA-seq) on biopsy tissue to map the cellular landscape of AIH and its diagnostic mimics. Unsupervised clustering on cell-type abundances alone largely separated AIH from non-AIH samples. Among individual populations, a subset of CD8 T-cells marked by high TOX and PD1 expression was the most discriminating feature: its enrichment perfectly distinguished AIH by both snRNA-seq and in situ density (AUC = 1.00), outperforming plasma cell abundance (AUC = 0.83). CD8TOX T-cell enrichment may therefore be the histologic lesion that marks the diagnosis of AIH.

Wolman disease (WD), the severe infantile form of lysosomal acid lipase deficiency, is a rare metabolic disorder caused by inactivating mutations in the LIPA gene. Although WD is characterized by profound hepatic dysfunction, experimental human systems capable of modelling multicellular liver pathology and supporting therapeutic testing remain limited. Here, we generated an isogenic human model of WD by introducing LIPA loss-of-function mutations into induced pluripotent stem cells and differentiating them into multicellular human liver organoids (HLO). LIPA-deficient HLO preserved hepatic lineage specification while recapitulating key biochemical and cellular features of WD, including loss of LIPA activity, lysosomal expansion, lipid accumulation, and activation of inflammatory and fibrogenic programs. Single-cell RNA sequencing resolved cell-type-specific disease states across hepatocyte-, stromal-, and biliary-like populations, revealing the emergence of a reactive biliary program consistent with ductular reaction, a complex tissue response associated with chronic liver injury. Importantly, this reactive biliary phenotype was supported by targeted gene-expression analysis in WD liver organoids and independently validated in liver tissue from mouse models and WD patients. Isolated LIPA-deficient cholangiocyte organoids failed to reproduce the DR-associated program, indicating that this response depends on multicellular interactions within the hepatic microenvironment rather than on biliary cell-autonomous dysfunction alone. Consistently, hepatocyte-directed AAV-mediated restoration of LIPA expression attenuated metabolic stress, inflammatory and fibrogenic programs, and suppressed ductular reaction both in organoids and in vivo. Together, these findings establish multicellular human liver organoids as a physiologically relevant platform for modelling emergent tissue-level responses in WD and for evaluating therapeutic rescue strategies in a human context.

BACKGROUNDMetabolic dysfunction-associated steatotic liver disease (MASLD) is a systemic immunometabolic disorder rapidly increasing worldwide, affecting nearly 38% of adults. Gut dysbiosis and host genetic factors, such as PNPLA3 I148M variant, modulate disease development and progression. Through the gut-liver axis, increased intestinal permeability enables microbial translocation to the liver, promoting inflammation and metabolic disruption. However, the composition and functional potential of the hepatic microbiome remain poorly characterized. Understanding its relationship with histological injury and genetic susceptibility may provide novel mechanistic insights. We hypothesized that the hepatic microbiome composition and function are associated with histological severity and PNPLA3 genotype in this disease. AIMTo characterize the hepatic microbiome and assess its association with histological severity and PNPLA3 genotype. METHODSThis cross-sectional observational study included 30 patients with MASLD from a tertiary care hospital. Liver tissue underwent shotgun metagenomic sequencing. Histological severity was assessed using the NAFLD Activity Score (NAS). PNPLA3 genotype was determined by PCR. Differential abundance and functional enrichment analyses were performed using MaAsLin2. Somatic variants were identified using Mutect2. Correlation networks were constructed using Spearmans correlation coefficients. RESULTSPatients with advanced histological injury (NAS [&ge;]5) and PNPLA3 I148M carriers showed a trend toward higher somatic mutational load and a markedly reduced microbial abundance. Analyses revealed broad compositional shifts across bacterial, fungal, viral, and eukaryotic taxa, affecting both commensal and context-dependent pathobiont lineages. Pseudomonas species were enriched, whereas Siphoviridae phages were depleted in advanced disease and PNPLA3 I148M carriers. Functional analysis revealed enrichment of pathways related to nutrient transport and metabolic stress adaptation, while TonB-associated functions were enriched in advanced liver injury but depleted in PNPLA3 I148M carriers. Network analysis identified Sphingomonas leidyi as a keystone node associated with hexosamine metabolism. Salmonella enterica abundance positively correlated with somatic variant burden, suggesting a link between microbial signatures and genomic instability. Histological progression and the risk PNPLA3 genotype were accompanied by marked topological simplification, reflecting less resilient community structures. CONCLUSIONSThe hepatic microbiome in MASLD is a low-biomass, polymicrobial ecosystem shaped by the host genetic background. Its functional activity, taxonomic composition and system architecture bidirectionally relate to liver DNA instability and the severity of histological damage. Core tipThis study characterizes the multi-kingdom hepatic microbiome in MASLD using FFPE-derived metagenomics. We demonstrate that microbial abundance-including bacteria, fungi, protozoa, and viruses- significantly decreases with increased histological severity and the PNPLA3 risk genotype. Rather than global diversity shifts, results showed that disease progression could be linked to specific functional adaptations and simplified microbial network connectivity. In addition, we described associations between specific taxa and somatic mutational burden, suggesting a link between microbial signals and genomic instability. These findings indicate that changes in the liver microbiome as a whole, rather than specific taxonomic modifications, influence MASLD pathophysiology.

Nicotine accumulates in the gut and drives non-alcoholic steatohepatitis (NASH) via the gut-liver axis, yet no effective clinical intervention is currently available. To address this challenge, the probiotic Escherichia coli Nissle 1917 (EcN) was engineered for in situ nicotine clearance in the gut. Mutational screening of nicotine oxidoreductase 2 (PpNicA2) identified a highly active variant, PpNicA2A107R. Its incorporation into EcN together with an electron transfer protein (CycN) and a newly identified transporter (T3/T7) yielded 80% nicotine-degrading activity. Chromosomal integration of this module generated a stable strain, EcN-N12, which in NASH mouse models depleted intestinal nicotine, rescued hepatic lipid metabolism, alleviated tissue damage, and intercepted the nicotine-mediated gut-liver axis pathological progression. This work thus offers an effective and clinically translatable approach for nicotine-associated diseases.

Sex differences strongly influence susceptibility to metabolic dysfunction-associated steatotic liver disease (MASLD), yet the regulatory mechanisms underlying these differences remain incompletely understood. To examine sex-specific hepatic adaptation to a high-fat (HF) diet mouse model of MASLD, we integrated proteomics, transcriptomics, and Oxford Nanopore direct RNA sequencing for transcriptome-wide m6A profiling in male and female mouse livers. Female mice were relatively protected from HF diet-induced hepatic steatosis and exhibited distinct proteome remodeling enriched for peroxisomal pathways. In contrast, transcriptomic responses in females were dominated by inflammatory signatures and did not recapitulate the metabolic adaptations observed at the protein level, revealing extensive RNA-protein discordance and post-transcriptional remodeling. Integrated RNA-protein analyses identified female-specific amplification of peroxisomal proteins despite modest transcript-level changes. HF diet also induced sex-specific remodeling of m6A RNA methylation and altered regulation of the m6A methylation system. Notably, reduced 3' UTR m6A methylation of peroxisomal transcripts inversely correlated with increased protein abundance relative to RNA expression in female mice. Together, these findings implicate m6A-associated post-transcriptional regulation in sex-specific hepatic adaptation to HF diet exposure and the basis for discordance between many of the mRNAs and proteins in the liver.

Mammalian energy homeostasis depends on coordinated metabolism across tissues, with the liver acting as a central hub for systemic energy balance and biosynthetic precursor supply. Although hepatic mitochondrial dysfunction is implicated in diverse pathologies, mitochondrial regulation across liver microanatomical space and time remains incompletely defined. Here, we mapped how mitochondrial- and nuclear-encoded genes supporting mitochondrial function vary along spatial gradients within the lobule and across the feeding-fasting cycle in mice. Integrating these transcriptomic features with quantitative measurements of mitochondrial morphology in periportal and pericentral hepatocytes, we showed that functional hepatocyte subtypes are distinguished by pronounced mitochondrial divergence, including cells with exceptionally low mitochondrial gene expression and reduced secretory protein production. We described that higher periportal oxidative phosphorylation relies on an exceptionally high periportal mitochondrial transcript fraction, while nuclear mitochondrial-function genes do not follow this pattern. The increased periportal mitochondrial transcript abundance coincided with substantially increased periportal cytoplasmic mitochondrial density. In humans, we recapitulated the higher periportal mitochondrial transcript abundance and showed that mitochondrial-function genes exhibited rhythmic expression patterns, more so in women. Together, these data establish a spatially and temporally resolved reference dataset of hepatic mitochondrial regulation that provides a reference for interpreting liver single-cell datasets and mechanistic pathophysiological studies.

Metastatic progression requires cancer cells to adapt to the unique constraints of distant organ microenvironments, yet the mechanisms that drive organ-specific adaptations remain poorly understood. Here, we show that the liver actively rewrites metastatic cancer cell identity, driving tumor cells toward a hepatobiliary progenitor-like state. Through integrated transcriptomic, proteomic, metabolomic, and epigenomic analyses of patient-derived rapid-autopsy samples and experimental models, we identify this state as selectively enriched in liver metastases. It is characterized by co-activation of hepatic and biliary/progenitor regulators HNF4A and SOX9 and is observed across multiple epithelial cancers, indicating a conserved response to the hepatic niche. Mechanistically, hepatocyte-derived TGF-{beta} and hypoxia converge to activate a HIF-1-ACLY axis, increasing nuclear acetyl-coenzyme A availability and histone acetylation at hepatic lineage regulatory elements to drive hepatobiliary reprogramming. This coordinated niche-response program can be captured transcriptionally and is associated with inferior overall survival. Disruption of this pathway suppresses hepatic reprogramming and impairs liver metastatic fitness. These findings identify the liver as an active determinant of metastatic cell fate, linking microenvironmental signaling to metabolic and chromatin remodeling programs that enable lineage plasticity. More broadly, they reveal organ-specific reprogramming as a fundamental principle of metastasis and a therapeutic vulnerability in liver metastases.

Hypoxia is a potent stressor and a major cause of {beta}-cell failure and loss after islet transplantation. Autophagy is a critical homeostatic mechanism that preserves organelle integrity and metabolic balance in cells under stress, but whether it supports {beta}-cell adaptation to sustained oxygen deprivation is unclear. Here, we used {beta}-cell-specific Atg5 knockout together with hypoxia and transplantation models, to demonstrate that autophagy is a major determinant of {beta}-cell survival during oxygen limitation and supports islet graft function. However, prolonged hypoxia suppressed autophagic flux, reduced lysosomal activity, and led to autophagosome accumulation, indicating failure of the lysosomal clearance pathway. This was accompanied by a marked reduction in transcription factor EB (TFEB) and its lysosomal target genes. Genetic and pharmacological activation of TFEB restored lysosomal gene expression and cathepsin B activity and improved {beta}-cell viability under hypoxia, implicating TFEB decline as a contributor to autophagy-lysosome dysfunction. Together, these findings outline a sequence in which autophagy initially safeguards {beta}-cells but becomes ineffective under sustained hypoxia as TFEB levels fall, identifying TFEB as a potential target to strengthen {beta}-cell resilience and survival in islet transplantation.

Complement factor D, also known as adipsin, is produced by adipose tissue, and the liver that links metabolic regulation with innate immunity. Despite its established systemic functions, the regulation of hepatic adipsin expression and its contribution to metabolic disease remain poorly defined. Here, we show that hepatic adipsin protein abundance is markedly increased in individuals with type 2 diabetes (T2D), and positively correlates with glycated hemoglobin, despite unchanged mRNA expression. Concordantly, hepatic adipsin protein levels were elevated in multiple murine models of hyperglycemia, including type 1 diabetes (T1D), T2D, and following fasting-refeeding transitions. In cultured hepatocytes, glucose exposure induced a rapid, dose-dependent increase in adipsin protein without altering transcript abundance, demonstrating post-transcriptional regulation. Mechanistically, glucose stimulates adipsin translation via dephosphorylation of eukaryotic initiation factor 2 (eIF2), and activation of the mammalian target of rapamycin, mediated by the 5' untranslated region of adipsin mRNA. Functionally, hepatocyte-specific depletion of adipsin impaired postprandial glucose tolerance, with reduced glucose uptake and a marked downregulation of glucose transporter type 2 (GLUT2). Taken together, these findings identify hepatic adipsin as a glucose-responsive translational target that couples nutrient availability to metabolic adaptation, revealing a new layer of regulation with potential relevance to diabetes pathogenesis. HighlightsO_LIHepatic adipsin protein increases in type 2 diabetes and correlates with glycemic status independent of mRNA expression. C_LIO_LIGlucose induces adipsin translation through eIF2 dephosphorylation and mTOR activation. C_LIO_LImTOR controls adipsin synthesis via structured 5'UTR of adipsin mRNA. C_LIO_LILiver-specific adipsin depletion impairs post-prandial glucose tolerance by downregulating GLUT2. C_LIO_LIHepatic adipsin acts as a glucose-responsive effector of glycemic control. C_LI

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related mortality worldwide despite recent therapeutic advances, driven in part by its marked etiological and molecular heterogeneity and the lack of broadly effective therapeutic targets. Identifying conserved tumor dependencies shared across distinct etiological backgrounds may provide new opportunities for targeted therapy. Here, we developed an integrative computational framework to systematically integrate transcriptomic, functional genomics, and clinical datasets for the identification and prioritization of candidate tumor dependency genes in liver cancer. We reanalyzed transcriptomic data from murine models of liver cancer driven by genotoxic (DEN), oncogenic (c-Myc), and inflammatory (lymphotoxin) stimuli, identifying more than 380 genes consistently upregulated across all tumor models. Functional enrichment analysis revealed a strong overrepresentation of cell cycle-related pathways and liver cancer signatures. Integration with DepMap dependency datasets identified 26 genes with strong dependency scores. Candidate genes were further prioritized by comparing their expression across models of liver regeneration, chronic liver injury, and liver cancer. Analysis of the TCGA-LIHC cohort confirmed significant overexpression of all 26 genes in human HCC, with high expression associated with poor patient survival. Together, these findings establish an integrative framework for identifying conserved tumor dependencies, providing a prioritized set of proliferation-associated genes for functional evaluation as therapeutic targets in HCC.

Type 1 diabetes (T1D) involves immune-mediated destruction of pancreatic {beta}-cells, yet current disease-modifying therapies mainly target immunity without enhancing {beta}-cell resilience. We show selective neuropeptide Y4 receptor (Y4R) agonism protects {beta}-cells while reshaping islet immunity across T1D models. Multi-modal localisation using cell sorting, qPCR, RNAscope and fluorescent ligand competition demonstrated predominant Y4R expression and functional accessibility on mouse and human {beta}-cells. Selective Y4R agonism was non-toxic and did not impair islet network integrity, Ca{superscript 2} dynamics, glucose-stimulated insulin secretion or systemic glucose tolerance. Y4R activation conferred cytoprotection against inflammatory cytokines, streptozotocin, lipotoxicity and ER stress, reducing caspase-3/7 activation and {beta}-cell loss whilst sustaining insulin release and promoting proliferation in both mouse and human islets. Bulk RNA-seq revealed a coordinated {beta}-cell resilience programme characterised by reinforced identity and insulin processing, KEAP1-NFE2L2-driven antioxidative and proteostatic activation, and suppression of EIF2 signalling and associated biosynthetic and ER stress pathways. Concurrently, Y4R agonism dampened pathogenic chemokine and cytokine networks, including CXCL10, CCL3/4/7 and IL-6, while preserving IL-2 and Foxp3 signals, thereby limiting CD8 T cell, CD4 T cell and macrophage chemotaxis toward cytokine-stressed islets. Reduced immune-cell recruitment was conserved in a fully human immune-islet system, where Y4R activation significantly attenuated IL-2-activated human PBMC migration and invasion toward cytokine-stressed human islets. In a stringent NY8.3 CD8 T cell adoptive-transfer model, systemic Y4R agonism significantly delayed diabetes onset. These data position Y4R as a {beta}-cell-centric therapeutic target coupling intrinsic resilience with local immune modulation, offering a complementary approach for {beta}-cell preservation in T1D and islet replacement therapies. Graphical abstractThe selective Y4 receptor agonist K22 binds {beta}-cell-enriched NPY4R in mouse and human islets, activates a {beta}-cell resilience programme that preserves insulin secretion under inflammatory and metabolic stress, and simultaneously dampens islet chemokine output, thereby limiting innate and adaptive immune-cell recruitment and delaying autoimmune diabetes onset. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=119 SRC="FIGDIR/small/736290v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@11af8d3org.highwire.dtl.DTLVardef@1c60d37org.highwire.dtl.DTLVardef@18dd142org.highwire.dtl.DTLVardef@1a56cdb_HPS_FORMAT_FIGEXP M_FIG C_FIG

The intermittent energy restriction (iER) represents an effective dietary strategy for improving metabolic diseases including metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes mellitus (T2DM), yet the underlying mechanisms remain elusive. In this study, we integrated human clinical data, mouse models, and in vitro experiments to investigate the role of iER in modulating the gut-liver axis in comorbid MASLD and T2DM. We demonstrate that an iER diet improves hyperglycemia, hepatic steatosis and decreases the abundance of gut pathogen Klebsiella pneumoniae, which is strongly associated with reductions in blood endotoxin, lipopolysaccharide (LPS) levels, suggesting a potential role of K. pneumoniae-derived LPS in mediating effects of the iER on hepatometabolic improvements. We confirm that K. pneumoniae-derived LPS exacerbates lipid accumulation and inflammation using an in vitro model. Mechanistically, we reveal a core target of protein lysine acetylation (Kac), hydroxyacyl-CoA dehydrogenase -subunit (HADHA) Lys353 in the liver of db/db mice through a multi-omics analysis. The iER decreases HADHA-K353 acetylation and enhances its enzyme activity. A Kac-mimicking mutation (K353R) increases its enzyme activity and stability, blocks its binding to the inflammasome adaptor ASC, and alleviates lipid accumulation and inflammation in K. pneumoniae-derived LPS induced in vitro model. This study provides novel insights into the potential benefits of the iER in comorbid MASLD and T2DM.

Metabolites are emerging as signaling molecules that mediate cellular function, extending beyond their well-established roles in metabolic pathways. Members of the solute carrier (SLC) family mediate metabolite transport across cellular compartments, raising the possibility that these proteins may sense environmental stimuli and regulate cellular biological processes by triggering signaling cascades linked to metabolite transport. This study investigated the response of the SLC25A family, a unique set of inner mitochondrial membrane-localized transporters, to cold as an environmental stimulus in mediating metabolic reprogramming; and whether this reprogramming, driven by the metabolites transported by SLC25A proteins, subsequently promotes the activation of thermogenesis in brown adipocytes. After screening members of the SLC25A family for their responsiveness to cold stimuli and brown adipose tissue (BAT) activation, we found that Slc25a34 was robustly induced under these conditions. We further demonstrated that Slc25a34 mediates the transport of adenosine monophosphate (AMP), derived from de novo glucose synthesis, from mitochondria to the cytosol. This transport potentiates AMP-activated protein kinase (AMPK) signaling and glycolytic flux in brown adipocytes, both of which facilitate BAT thermogenesis during cold exposure. Intriguingly, cold exposure directly promoted the activation of peroxisome proliferator-activated receptor gamma (PPAR{gamma}), which transcriptionally upregulated Slc25a34 expression. More importantly, genetic ablation of Slc25a34 impaired BAT thermogenesis. Thus, our study reveals a novel cold-induced metabolite-sensing pathway, where Slc25a34-mediated AMP transport between mitochondria and the cytosol serves as a critical signal for activating BAT thermogenesis. These findings provide compelling evidence that metabolite transport across cellular compartments acts as a key driver of cellular physiology, thereby offering novel insights into metabolite-based therapeutic strategies for metabolic diseases. HighlightsO_LISlc25a34 is cold-responsive and transcriptionally regulated by PPAR{gamma}. C_LIO_LISlc25a34 functions specifically to mediate the mitochondrial-to-cytosolic transport of AMP in brown adipocytes. C_LIO_LIMitochondrially sequestered de novo synthesized AMP acts as a signaling reservoir, and its Slc25a34-mediated efflux to the cytosol activates AMPK and glycolysis, supporting BAT thermogenesis. C_LI

Pancreatic cancer (PC) exhibits a striking association with depression, with neuropsychiatric symptoms frequently preceding diagnosis. However, the biological mechanisms linking pancreatic tumor development to central nervous system dysfunction remain poorly understood. Here, we investigated the impact of PC progression on adult hippocampal neurogenesis using complementary orthotopic xenograft and genetically engineered mouse models. Tumor-bearing mice developed depressive-like behavioral abnormalities accompanied by reduced adult hippocampal neurogenesis, including depletion of neural stem cell populations and immature neurons in both dorsal and ventral dentate gyrus regions. In the genetic model, neurogenic impairment progressed in parallel with disease severity. Exposure of primary hippocampal neural stem cells to serum derived from tumor-bearing mice selectively impaired cell survival, indicating that circulating factors are sufficient to compromise neurogenic capacity. Consistent with this, cytokine profiling revealed profound systemic inflammatory alterations, with IL-6 emerging as the only cytokine consistently elevated across both models. Together, our findings identify disruption of the adult hippocampal neurogenic niche as a previously unrecognized consequence of pancreatic cancer progression and provide a biological framework for pancreatic cancer-associated depression.

Fibrotic extracellular matrix (ECM) is not merely a structural scaffold but an instructive signaling interface that shapes epithelial cell state. However, the molecular cues by which matrix remodeling controls tubular metabolism during kidney fibrosis remain poorly defined. Here, we identify Fibulin-2 (FBLN2) as a fibroblast-derived matrix cue that transduces fibrotic ECM remodeling into tubular mitochondrial metabolic reprogramming. Using fibroblast-selective deletion of Smoothened (Smo) across distinct fibroblast subpopulations, we found that loss of fibroblast Smo preserved kidney function and attenuated fibrosis in mouse models of chronic kidney injury. Multi-omics profiling revealed coordinated remodeling of the fibrotic matrisome, highlighted by suppression of FBLN2, an ECM glycoprotein genetically linked to kidney function in humans. Mechanistically, FBLN2 engaged EGFR in tubular epithelial cells and activated EGFR-AKT signaling in a non-canonical ligand-like manner. This signaling axis suppressed acetyl-CoA acetyltransferase 1 (ACAT1), a mitochondrial regulator of fatty acid oxidation and amino acid metabolism. Disruption of fibroblast Smo-FBLN2 signaling restored ACAT1-dependent oxidative metabolism and reduced tubular fibrotic activation. Spatial lipidomics revealed compartment-specific lipid remodeling associated with altered mitochondrial fatty acid metabolism, including acylcarnitine and phospholipid changes linked to reduced fibrotic injury. Together, these findings define a Fibulin-2-EGFR-ACAT1 matrix-to-metabolism signaling axis that couples fibrotic ECM remodeling to tubular mitochondrial metabolism during kidney fibrosis.

Glandular architecture - the coordination of lumen-containing structures by an apical-basal polarised epithelium - is frequently maintained in colorectal cancer (CRC), yet whether it actively contributes to tumour progression or metastatic competence remains unclear. Here, we identify Podocalyxin (PODXL), a developmental regulator of epithelial lumen formation, as a key determinant of glandular tumour architecture in CRC. PODXL is upregulated in CRC, particularly in poor-prognosis Consensus Molecular Subtype 4 (CMS4) tumours, where high expression predicts reduced survival. Using genetically engineered mouse models, matched organoids, human cell lines and xenografts, we show that PODXL promotes organisation of CRC cells into gland-like, lumen-containing structures. Loss of PODXL disrupts glandular architecture in both primary tumours and liver metastases, reducing tumour growth and metastatic colonisation. Mechanistically, TGF-{beta} signalling drives PODXL upregulation. Together, these findings establish glandular architecture as an active determinant of CRC progression and identify PODXL as a functional contributor rather than merely a prognostic biomarker.