bims-nimamd Biomed News
on Neuroimmunity and neuroinflammation in ageing and metabolic disease
Issue of 2025–04–20
thirty-one papers selected by
Fawaz Alzaïd, Sorbonne Université
  1. Mutant CEBPA promotes tolerance to inflammatory stress through deficient AP-1 activation.
  2. Why women experience Alzheimer's disease differently from men.
  3. Reframe perspectives on Alzheimer's disease.
  4. Metabolic rewiring caused by mitochondrial dysfunction promotes mTORC1-dependent skeletal aging.
  5. You're only human: a six-step strategy to surviving your PhD.
  6. Signalling from adipose tissue to the brain is not just about leptin.
  7. Africa CDC must become financially independent.
  8. scMultiSim: simulation of single-cell multi-omics and spatial data guided by gene regulatory networks and cell-cell interactions.
  9. Dietary methionine restriction started late in life promotes healthy aging in a sex-specific manner.
  10. Elevated mitochondrial membrane potential is a therapeutic vulnerability in Dnmt3a-mutant clonal hematopoiesis.
  11. Engineering mitochondrial DNA deletions in human cells improves disease modeling.
  12. Five years on: how Brexit changed three scientists' careers.
  13. Twenty years of genome-wide association studies.
  14. Not a 'DEI hire'.
  15. High-resolution dynamic imaging of chromatin DNA communication using Oligo-LiveFISH.
  16. Prdm16-dependent antigen-presenting cells induce tolerance to gut antigens.
  17. Cell-intrinsic insulin signaling defects in human iPS cell-derived hepatocytes in type 2 diabetes.
  18. Coupling of ribosome biogenesis and translation initiation in human mitochondria.
  19. Activin B improves glucose metabolism via induction of Fgf21 and hepatic glucagon resistance.
  20. Spatial analysis of mitochondrial gene expression reveals dynamic translation hubs and remodeling in stress.
  21. Not just obesity: GLP-1 receptor agonists advance on addiction.
  22. Do infections have a role in Alzheimer's disease?
  23. GDF15 links adipose tissue lipolysis with anxiety.
  24. Mitochondrial complexity is regulated at ER-mitochondria contact sites via PDZD8-FKBP8 tethering.
  25. Active control of mitochondrial network morphology by metabolism-driven redox state.
  26. Age-related blood condition counteracted with a common diabetes drug.
  27. Spatial regulation of glucose and lipid metabolism by hepatic insulin signaling.
  28. The extra-islet pancreas supports autoimmunity in human type 1 diabetes.
  29. Itaconate modulates immune responses via inhibition of peroxiredoxin 5.
  30. Virus-associated inflammation imprints an inflammatory profile on monocyte-derived macrophages in the human liver.
  31. Integrated analysis of transcriptional and metabolic responses to mitochondrial stress.
  1. Nat Commun. 2025 Apr 12. 16(1): 3492
    Mutant CEBPA promotes tolerance to inflammatory stress through deficient AP-1 activation.
    Maria Cadefau-Fabregat, Gerard Martínez-Cebrián, Lucía Lorenzi, Felix D Weiss, Anne-Katrine Frank, José Manuel Castelló-García, Eric Julià-Vilella, Andrés Gámez-García, Laura Yera, Carini Picardi Morais de Castro, Yi-Fang Wang, Felix Meissner, Alejandro Vaquero, Matthias Merkenschlager, Bo T Porse, Sergi Cuartero.
      The CEBPA transcription factor is frequently mutated in acute myeloid leukemia (AML). Mutations in the CEBPA gene, which are typically biallelic, result in the production of a shorter isoform known as p30. Both the canonical 42-kDa isoform (p42) and the AML-associated p30 isoform bind chromatin and activate transcription, but the specific transcriptional programs controlled by each protein and how they are linked to a selective advantage in AML is not well understood. Here, we show that cells expressing the AML-associated p30 have reduced baseline inflammatory gene expression and display altered dynamics of transcriptional induction in response to LPS, consequently impacting cytokine secretion. This confers p30-expressing cells an increased resistance to the adverse effects of prolonged exposure to inflammatory signals. Mechanistically, we show that these differences primarily arise from the differential regulation of AP-1 family proteins. In addition, we find that the impaired function of the AP-1 member ATF4 in p30-expressing cells alters their response to ER stress. Collectively, these findings uncover a link between mutant CEBPA, inflammation and the stress response, potentially revealing a vulnerability in AML.
    DOI:  https://doi.org/10.1038/s41467-025-58712-7
  2. Nature. 2025 Apr;640(8059): S14-S17
    Why women experience Alzheimer's disease differently from men.
    Katherine Bourzac.
      
    Keywords:  Alzheimer's disease; Medical research; Neurodegeneration
    DOI:  https://doi.org/10.1038/d41586-025-01106-y
  3. Nature. 2025 Apr;640(8059): S1
    Reframe perspectives on Alzheimer's disease.
    Richard Hodson.
      
    Keywords:  Alzheimer's disease; Brain; Medical research; Neurodegeneration
    DOI:  https://doi.org/10.1038/d41586-025-01100-4
  4. Sci Adv. 2025 Apr 18. 11(16): eads1842
    Metabolic rewiring caused by mitochondrial dysfunction promotes mTORC1-dependent skeletal aging.
    Kristina Bubb, Julia Etich, Kristina Probst, Tanvi Parashar, Maximilian Schuetter, Frederik Dethloff, Susanna Reincke, Janica L Nolte, Marcus Krüger, Ursula Schlötzer-Schrehard, Julian Nüchel, Constantinos Demetriades, Patrick Giavalisco, Jan Riemer, Bent Brachvogel.
      Decline of mitochondrial respiratory chain (mtRC) capacity is a hallmark of mitochondrial diseases. Patients with mtRC dysfunction often present reduced skeletal growth as a sign of premature cartilage degeneration and aging, but how metabolic adaptations contribute to this phenotype is poorly understood. Here we show that, in mice with impaired mtRC in cartilage, reductive/reverse TCA cycle segments are activated to produce metabolite-derived amino acids and stimulate biosynthesis processes by mechanistic target of rapamycin complex 1 (mTORC1) activation during a period of massive skeletal growth and biomass production. However, chronic hyperactivation of mTORC1 suppresses autophagy-mediated organelle recycling and disturbs extracellular matrix secretion to trigger chondrocytes death, which is ameliorated by targeting the reductive metabolism. These findings explain how a primarily beneficial metabolic adaptation response required to counterbalance the loss of mtRC function, eventually translates into profound cell death and cartilage tissue degeneration. The knowledge of these dysregulated key nutrient signaling pathways can be used to target skeletal aging in mitochondrial disease.
    DOI:  https://doi.org/10.1126/sciadv.ads1842
  5. Nature. 2025 Apr 16.
    You're only human: a six-step strategy to surviving your PhD.
    Gauthier Weissbart.
      
    Keywords:  Careers; Lab life; Research management
    DOI:  https://doi.org/10.1038/d41586-025-00967-7
  6. Nat Metab. 2025 Apr 15.
    Signalling from adipose tissue to the brain is not just about leptin.
    Peter Arner.
      
    DOI:  https://doi.org/10.1038/s42255-025-01277-y
  7. Nature. 2025 Apr;640(8059): 602
    Africa CDC must become financially independent.
    Nelson Aghogho Evaborhene, Jessica Oga, Echezona Udokanma.
      
    Keywords:  Funding; Policy; Public health
    DOI:  https://doi.org/10.1038/d41586-025-01201-0
  8. Nat Methods. 2025 Apr 17.
    scMultiSim: simulation of single-cell multi-omics and spatial data guided by gene regulatory networks and cell-cell interactions.
    Hechen Li, Ziqi Zhang, Michael Squires, Xi Chen, Xiuwei Zhang.
      Simulated single-cell data are essential for designing and evaluating computational methods in the absence of experimental ground truth. Here we present scMultiSim, a comprehensive simulator that generates multimodal single-cell data encompassing gene expression, chromatin accessibility, RNA velocity and spatial cell locations while accounting for the relationships between modalities. Unlike existing tools that focus on limited biological factors, scMultiSim simultaneously models cell identity, gene regulatory networks, cell-cell interactions and chromatin accessibility while incorporating technical noise. Moreover, it allows users to adjust each factor's effect easily. Here we show that scMultiSim generates data with expected biological effects, and demonstrate its applications by benchmarking a wide range of computational tasks, including multimodal and multi-batch data integration, RNA velocity estimation, gene regulatory network inference and cell-cell interaction inference using spatially resolved gene expression data. Compared to existing simulators, scMultiSim can benchmark a much broader range of existing computational problems and even new potential tasks.
    DOI:  https://doi.org/10.1038/s41592-025-02651-0
  9. Sci Adv. 2025 Apr 18. 11(16): eads1532
    Dietary methionine restriction started late in life promotes healthy aging in a sex-specific manner.
    Ulalume Hernández-Arciga, Ceda Stamenkovic, Shweta Yadav, Chiara Nicoletti, Wafaa N Albalawy, Farazdaq Al Hammood, Tiffany Fuentes Gonzalez, Maitreyi U Naikwadi, Aidan Graham, Christian Smarz, Gabriela J Little, Sean-Paul G Williams, Brenda McMahon, Ian J Sipula, Amber M Vandevender, Byron Chuan, Diana Cooke, Antonio F M Pinto, Lisa C Flores, Hannah L Hartman, Jolene K Diedrich, Robert T Brooke, Jonathan K Alder, Krystle A Frahm, Laura E Pascal, Emma Stolt, Hannibal Troensegaard, Bente Øvrebø, Amany Elshorbagy, Elsa Molina, Kathrine J Vinknes, Roderick J Tan, Ora A Weisz, Marta Bueno, Oliver Eickelberg, Matthew L Steinhauser, Toren Finkel, Gene P Ables, Yuji Ikeno, Thomas Olsen, Alessandra Sacco, Michael J Jurczak, Stacey J Sukoff Rizzo, Andrey A Parkhitko.
      Aging is associated with dysregulated methionine metabolism and increased levels of enzymes in the tyrosine degradation pathway (TDP). To investigate the efficacy of targeting either methionine metabolism or the TDP for healthspan improvement in advanced age, we initiated dietary MetR or TDP inhibition in 18-month-old C57BL/6J mice. MetR significantly improved neuromuscular function, metabolic health, lung function, and frailty. In addition, we confirmed improved neuromuscular function from dietary MetR in 5XFAD mice, whose weight was not affected by MetR. We did not observe benefits with TDP inhibition. Single-nucleus RNA and ATAC sequencing of muscle revealed cell type-specific responses to MetR, although MetR did not significantly affect mouse aging epigenetic clock markers. Similarly, an 8-week MetR intervention in a human trial (NCT04701346) showed no significant impact on epigenetic clocks. The observed benefits from late-life MetR provide translational rationale to develop MetR mimetics as an antiaging intervention.
    DOI:  https://doi.org/10.1126/sciadv.ads1532
  10. Nat Commun. 2025 Apr 16. 16(1): 3306
    Elevated mitochondrial membrane potential is a therapeutic vulnerability in Dnmt3a-mutant clonal hematopoiesis.
    Kira A Young, Mohsen Hosseini, Jayna J Mistry, Claudia Morganti, Taylor S Mills, Xiurong Cai, Brandon T James, Griffin J Nye, Natalie R Fournier, Veronique Voisin, Ali Chegini, Aaron D Schimmer, Gary D Bader, Grace Egan, Marc R Mansour, Grant A Challen, Eric M Pietras, Kelsey H Fisher-Wellman, Keisuke Ito, Steven M Chan, Jennifer J Trowbridge.
      The competitive advantage of mutant hematopoietic stem and progenitor cells (HSPCs) underlies clonal hematopoiesis (CH). Drivers of CH include aging and inflammation; however, how CH-mutant cells gain a selective advantage in these contexts is an unresolved question. Using a murine model of CH (Dnmt3aR878H/+), we discover that mutant HSPCs sustain elevated mitochondrial respiration which is associated with their resistance to aging-related changes in the bone marrow microenvironment. Mutant HSPCs have DNA hypomethylation and increased expression of oxidative phosphorylation gene signatures, increased functional oxidative phosphorylation capacity, high mitochondrial membrane potential (Δψm), and greater dependence on mitochondrial respiration compared to wild-type HSPCs. Exploiting the elevated Δψm of mutant HSPCs, long-chain alkyl-TPP molecules (MitoQ, d-TPP) selectively accumulate in the mitochondria and cause reduced mitochondrial respiration, mitochondrial-driven apoptosis and ablate the competitive advantage of HSPCs ex vivo and in vivo in aged recipient mice. Further, MitoQ targets elevated mitochondrial respiration and the selective advantage of human DNMT3A-knockdown HSPCs, supporting species conservation. These data suggest that mitochondrial activity is a targetable mechanism by which CH-mutant HSPCs gain a selective advantage over wild-type HSPCs.
    DOI:  https://doi.org/10.1038/s41467-025-57238-2
  11. Nat Biotechnol. 2025 Apr;43(4): 501
    Engineering mitochondrial DNA deletions in human cells improves disease modeling.
    Iris Marchal.
      
    DOI:  https://doi.org/10.1038/s41587-025-02652-6
  12. Nature. 2025 Apr 14.
    Five years on: how Brexit changed three scientists' careers.
    Anna Napolitano.
      
    Keywords:  Careers; Funding; Government; Institutions
    DOI:  https://doi.org/10.1038/d41586-025-00858-x
  13. Nature. 2025 Apr 15.
    Twenty years of genome-wide association studies.
    Lorraine Southam, Eleftheria Zeggini.
      
    Keywords:  Diseases; Genetics; Genomics; Technology
    DOI:  https://doi.org/10.1038/d41586-025-01128-6
  14. Science. 2025 Apr 18. 388(6744): 330
    Not a 'DEI hire'.
    Troy Christopher Dildine.
      
    DOI:  https://doi.org/10.1126/science.ady1733
  15. Cell. 2025 Apr 11. pii: S0092-8674(25)00350-2. [Epub ahead of print]
    High-resolution dynamic imaging of chromatin DNA communication using Oligo-LiveFISH.
    Yanyu Zhu, Ashwin Balaji, Mengting Han, Leonid Andronov, Anish R Roy, Zheng Wei, Crystal Chen, Leanne Miles, Sa Cai, Zhengxi Gu, Ariana Tse, Betty Chentzu Yu, Takeshi Uenaka, Xueqiu Lin, Andrew J Spakowitz, W E Moerner, Lei S Qi.
      Three-dimensional (3D) genome dynamics are crucial for cellular functions and disease. However, real-time, live-cell DNA visualization remains challenging, as existing methods are often confined to repetitive regions, suffer from low resolution, or require complex genome engineering. Here, we present Oligo-LiveFISH, a high-resolution, reagent-based platform for dynamically tracking non-repetitive genomic loci in diverse cell types, including primary cells. Oligo-LiveFISH utilizes fluorescent guide RNA (gRNA) oligo pools generated by computational design, in vitro transcription, and chemical labeling, delivered as ribonucleoproteins. Utilizing machine learning, we characterized the impact of gRNA design and chromatin features on imaging efficiency. Multi-color Oligo-LiveFISH achieved 20-nm spatial resolution and 50-ms temporal resolution in 3D, capturing real-time enhancer and promoter dynamics. Our measurements and dynamic modeling revealed two distinct modes of chromatin communication, and active transcription slows enhancer-promoter dynamics at endogenous genes like FOS. Oligo-LiveFISH offers a versatile platform for studying 3D genome dynamics and their links to cellular processes and disease.
    Keywords:  CRISPR imaging; DNA communication; Oligo-LiveFISH; dynamic tracking; enhancer-promoter interaction; high-resolution imaging; live DNA imaging; non-repetitive genome imaging; polymer modeling; primary cell
    DOI:  https://doi.org/10.1016/j.cell.2025.03.032
  16. Nature. 2025 Apr 14.
    Prdm16-dependent antigen-presenting cells induce tolerance to gut antigens.
    Liuhui Fu, Rabi Upadhyay, Maria Pokrovskii, Francis M Chen, Gabriela Romero-Meza, Adam Griesemer, Dan R Littman.
      The gastrointestinal tract is continuously exposed to foreign antigens in food and commensal microbes with potential to induce adaptive immune responses. Peripherally induced T regulatory (pTreg) cells are essential for mitigating inflammatory responses to these agents1-4. While RORγt+ antigen-presenting cells (RORγt-APCs) were shown to program gut microbiota-specific pTreg5-7, their definition remains incomplete, and the APC responsible for food tolerance has remained elusive. Here, we identify an APC subset required for differentiation of both food- and microbiota-specific pTreg cells and for establishment of oral tolerance. Development and function of these APCs require expression of the transcription factors Prdm16 and RORγt, as well as a unique Rorc(t) cis-regulatory element. Gene expression, chromatin accessibility, and surface marker analysis establish the pTreg-inducing APCs as myeloid in origin, distinct from ILC3, and sharing epigenetic profiles with classical dendritic cells (cDC), and designate them Prdm16+ RORγt+ tolerizing DC (tolDC). Upon genetic perturbation of tolDC, we observe a substantial increase in food antigen-specific T helper 2 (Th2) cells in lieu of pTreg, leading to compromised tolerance in mouse models of asthma and food allergy. Single-cell analyses of freshly resected mesenteric lymph nodes from a human organ donor, as well as multiple specimens of human intestine and tonsil, reveal candidate tolDC with co-expression of PRDM16 and RORC and an extensive transcriptome shared with mice, highlighting an evolutionarily conserved role across species. Our findings suggest that a better understanding of how tolDC develop and how they regulate T cell responses to food and microbial antigens could offer new insights into developing therapeutic strategies for autoimmune and allergic diseases as well as organ transplant tolerance.
    DOI:  https://doi.org/10.1038/s41586-025-08982-4
  17. J Clin Invest. 2025 Apr 15. pii: e183513. [Epub ahead of print]135(8):
    Cell-intrinsic insulin signaling defects in human iPS cell-derived hepatocytes in type 2 diabetes.
    Arijeet K Gattu, Maria Tanzer, Tomer M Yaron-Barir, Jared L Johnson, Ashok Kumar Jayavelu, Hui Pan, Jonathan M Dreyfuss, Lewis C Cantley, Matthias Mann, C Ronald Kahn.
      Hepatic insulin resistance is central to type 2 diabetes (T2D) and metabolic syndrome, but defining the molecular basis of this defect in humans is challenging because of limited tissue access. Utilizing inducible pluripotent stem cells differentiated into hepatocytes from control individuals and patients with T2D and liquid chromatography with tandem mass spectrometry-based (LC-MS/MS-based) phosphoproteomics analysis, we identified a large network of cell-intrinsic alterations in signaling in T2D. Over 300 phosphosites showed impaired or reduced insulin signaling, including losses in the classical insulin-stimulated PI3K/AKT cascade and their downstream targets. In addition, we identified over 500 phosphosites of emergent, i.e., new or enhanced, signaling. These occurred on proteins involved in the Rho-GTPase pathway, RNA metabolism, vesicle trafficking, and chromatin modification. Kinome analysis indicated that the impaired phosphorylation sites represented reduced actions of AKT2/3, PKCθ, CHK2, PHKG2, and/or STK32C kinases. By contrast, the emergent phosphorylation sites were predicted to be mediated by increased action of the Rho-associated kinases 1 and 2 (ROCK1/2), mammalian STE20-like protein kinase 4 (MST4), and/or branched-chain α-ketoacid dehydrogenase kinase (BCKDK). Inhibiting ROCK1/2 activity in T2D induced pluripotent stem cell-derived hepatocytes restored some of the alterations in insulin action. Thus, insulin resistance in the liver in T2D did not simply involve a loss of canonical insulin signaling but the also appearance of new phosphorylations representing a change in the balance of multiple kinases. Together, these led to altered insulin action in the liver and identified important targets for the therapy of hepatic insulin resistance.
    Keywords:  Adult stem cells; Diabetes; Endocrinology; Hepatology; Metabolism
    DOI:  https://doi.org/10.1172/JCI183513
  18. Nat Commun. 2025 Apr 17. 16(1): 3641
    Coupling of ribosome biogenesis and translation initiation in human mitochondria.
    Marleen Heinrichs, Anna Franziska Finke, Shintaro Aibara, Angelique Krempler, Angela Boshnakovska, Peter Rehling, Hauke S Hillen, Ricarda Richter-Dennerlein.
      Biogenesis of mitoribosomes requires dedicated chaperones, RNA-modifying enzymes, and GTPases, and defects in mitoribosome assembly lead to severe mitochondriopathies in humans. Here, we characterize late-step assembly states of the small mitoribosomal subunit (mtSSU) by combining genetic perturbation and mutagenesis analysis with biochemical and structural approaches. Isolation of native mtSSU biogenesis intermediates via a FLAG-tagged variant of the GTPase MTG3 reveals three distinct assembly states, which show how factors cooperate to mature the 12S rRNA. In addition, we observe four distinct primed initiation mtSSU states with an incompletely matured rRNA, suggesting that biogenesis and translation initiation are not mutually exclusive processes but can occur simultaneously. Together, these results provide insights into mtSSU biogenesis and suggest a functional coupling between ribosome biogenesis and translation initiation in human mitochondria.
    DOI:  https://doi.org/10.1038/s41467-025-58827-x
  19. Nat Commun. 2025 Apr 17. 16(1): 3678
    Activin B improves glucose metabolism via induction of Fgf21 and hepatic glucagon resistance.
    Naoki Kobayashi, Yukiko Okazaki, Aya Iwane, Kazuo Hara, Momoko Horikoshi, Motoharu Awazawa, Kotaro Soeda, Maya Matsushita, Takayoshi Sasako, Kotaro Yoshimura, Nobuyuki Itoh, Kenta Kobayashi, Yasuyuki Seto, Toshimasa Yamauchi, Hiroyuki Aburatani, Matthias Blüher, Takashi Kadowaki, Kohjiro Ueki.
      Orchestrated hormonal interactions in response to feeding and fasting play a pivotal role in regulating glucose homeostasis. Here, we show that in obesity, the production of follistatin-like 3 (FSTL3), an endogenous inhibitor of Activin B, in adipose tissue is increased in both mice and humans. The knockdown of FSTL3 improves insulin sensitivity and glucose tolerance in diabetic obese db/db mice. Notably, the overexpression of Activin B, a member of the TGFβ superfamily that is induced in liver sinusoidal endothelial cells by fasting, exerts multiple metabolically beneficial effects, including improvement of insulin sensitivity, suppression of hepatic glucose production, and enhancement of glucose-stimulated insulin secretion, all of which are attenuated by the overexpression of FSTL3. Activin B increases insulin sensitivity and reduces fat by inducing fibroblast growth factor 21 (FGF21) while suppressing glucagon action in the liver by increasing phosphodiesterase 4 B (PDE4B), leading to hepatic glucagon resistance and resultant hyperglucagonemia. Activin B-induced hyperglucagonemia enhances glucose-stimulated insulin secretion by stimulating glucagon-like peptide-1 (GLP-1) receptor in pancreatic β-cells. Thus, enhancing the action of Activin B which improves multiple components of the pathogenesis of diabetes may be a promising strategy for diabetes treatment.
    DOI:  https://doi.org/10.1038/s41467-025-58836-w
  20. Sci Adv. 2025 Apr 18. 11(16): eads6830
    Spatial analysis of mitochondrial gene expression reveals dynamic translation hubs and remodeling in stress.
    Adam Begeman, John A Smolka, Ahmad Shami, Tejashree Pradip Waingankar, Samantha C Lewis.
      Protein- and RNA-rich bodies contribute to the spatial organization of gene expression in the cell and are also sites of quality control critical to cell fitness. In most eukaryotes, mitochondria harbor their own genome, and all steps of mitochondrial gene expression co-occur within a single compartment-the matrix. Here, we report that processed mitochondrial RNAs are consolidated into micrometer-scale translation hubs distal to mitochondrial DNA transcription and RNA processing sites in human cells. We find that, during stress, mitochondrial messenger and ribosomal RNA are sequestered in mesoscale bodies containing mitoribosome components, concurrent with suppression of active translation. Stress bodies are triggered by proteotoxic stress downstream of double-stranded RNA accumulation in cells lacking unwinding activity of the highly conserved helicase SUPV3L1/SUV3. We propose that the spatial organization of nascent polypeptide synthesis into discrete domains serves to throttle the flow of genetic information to support recovery of mitochondrial quality control.
    DOI:  https://doi.org/10.1126/sciadv.ads6830
  21. Nat Biotechnol. 2025 Apr;43(4): 455-457
    Not just obesity: GLP-1 receptor agonists advance on addiction.
    Cormac Sheridan.
      
    DOI:  https://doi.org/10.1038/s41587-025-02644-6
  22. Nature. 2025 Apr;640(8059): S8-S10
    Do infections have a role in Alzheimer's disease?
    Michael Eisenstein.
      
    Keywords:  Alzheimer's disease; Brain; Neurodegeneration; Neuroscience
    DOI:  https://doi.org/10.1038/d41586-025-01104-0
  23. Nat Metab. 2025 Apr 15.
    GDF15 links adipose tissue lipolysis with anxiety.
    Logan K Townsend, Dongdong Wang, Carly M Knuth, Russta Fayyazi, Ahmad Mohammad, Léa J Becker, Evangelia E Tsakiridis, Eric M Desjardins, Zeel Patel, Celina M Valvano, Junfeng Lu, Alice E Payne, Ofure Itua, Kyle D Medak, Daniel M Marko, Jonathan D Schertzer, David C Wright, Shawn M Beaudette, Katherine M Morrison, André C Carpentier, Denis P Blondin, Rebecca E K MacPherson, Jordan G McCall, Marc G Jeschke, Gregory R Steinberg.
      Psychological stress changes both behaviour and metabolism to protect organisms. Adrenaline is an important driver of this response. Anxiety correlates with circulating free fatty acid levels and can be alleviated by a peripherally restricted β-blocker, suggesting a peripheral signal linking metabolism with behaviour. Here we show that adrenaline, the β3 agonist CL316,243 and acute restraint stress induce growth differentiation factor 15 (GDF15) secretion in white adipose tissue of mice. Genetic inhibition of adipose triglyceride lipase or genetic deletion of β-adrenergic receptors blocks β-adrenergic-induced increases in GDF15. Increases in circulating GDF15 require lipolysis-induced free fatty acid stimulation of M2-like macrophages within white adipose tissue. Anxiety-like behaviour elicited by adrenaline or restraint stress is eliminated in mice lacking the GDF15 receptor GFRAL. These data provide molecular insights into the mechanisms linking metabolism and behaviour and suggest that inhibition of GDF15-GFRAL signalling might reduce acute anxiety.
    DOI:  https://doi.org/10.1038/s42255-025-01264-3
  24. Nat Commun. 2025 Apr 17. 16(1): 3401
    Mitochondrial complexity is regulated at ER-mitochondria contact sites via PDZD8-FKBP8 tethering.
    Koki Nakamura, Saeko Aoyama-Ishiwatari, Takahiro Nagao, Mohammadreza Paaran, Christopher J Obara, Yui Sakurai-Saito, Jake Johnston, Yudan Du, Shogo Suga, Masafumi Tsuboi, Makoto Nakakido, Kouhei Tsumoto, Yusuke Kishi, Yukiko Gotoh, Chulhwan Kwak, Hyun-Woo Rhee, Jeong Kon Seo, Hidetaka Kosako, Clint Potter, Bridget Carragher, Jennifer Lippincott-Schwartz, Franck Polleux, Yusuke Hirabayashi.
      Mitochondria-ER membrane contact sites (MERCS) represent a fundamental ultrastructural feature underlying unique biochemistry and physiology in eukaryotic cells. The ER protein PDZD8 is required for the formation of MERCS in many cell types, however, its tethering partner on the outer mitochondrial membrane (OMM) is currently unknown. Here we identify the OMM protein FKBP8 as the tethering partner of PDZD8 using a combination of unbiased proximity proteomics, CRISPR-Cas9 endogenous protein tagging, Cryo-electron tomography, and correlative light-electron microscopy. Single molecule tracking reveals highly dynamic diffusion properties of PDZD8 along the ER membrane with significant pauses and captures at MERCS. Overexpression of FKBP8 is sufficient to narrow the ER-OMM distance, whereas independent versus combined deletions of these two proteins demonstrate their interdependence for MERCS formation. Furthermore, PDZD8 enhances mitochondrial complexity in a FKBP8-dependent manner. Our results identify a novel ER-mitochondria tethering complex that regulates mitochondrial morphology in mammalian cells.
    DOI:  https://doi.org/10.1038/s41467-025-58538-3
  25. Proc Natl Acad Sci U S A. 2025 Apr 22. 122(16): e2421953122
    Active control of mitochondrial network morphology by metabolism-driven redox state.
    Gaurav Singh, Vineeth Vengayil, Aayushee Khanna, Swagata Adhikary, Sunil Laxman.
      Mitochondria are dynamic organelles that constantly change morphology. What controls mitochondrial morphology however remains unresolved. Using actively respiring yeast cells growing in distinct carbon sources, we find that mitochondrial morphology and activity are unrelated. Cells can exhibit fragmented or networked mitochondrial morphology in different nutrient environments independent of mitochondrial activity. Instead, mitochondrial morphology is controlled by the intracellular redox state, which itself depends on the nature of electron entry into the electron transport chain (ETC)-through complex I/II or directly to coenzyme Q/cytochrome c. In metabolic conditions where direct electron entry is high, reactive oxygen species (ROS) increase, resulting in an oxidized cytosolic environment and rapid mitochondrial fragmentation. Decreasing direct electron entry into the ETC by genetic or chemical means, or reducing the cytosolic environment rapidly restores networked morphologies. Using controlled disruptions of electron flow to alter ROS and redox state, we demonstrate minute-scale, reversible control between networked and fragmented forms in an activity-independent manner. Mechanistically, the fission machinery through Dnm1 responds in minute-scale to redox state changes, preceding the change in mitochondrial form. Thus, the metabolic state of the cell and its consequent cellular redox state actively control mitochondrial form.
    Keywords:  electron transport chain; mitochondrial network; reactive oxygen species; redox state
    DOI:  https://doi.org/10.1073/pnas.2421953122
  26. Nature. 2025 Apr 16.
    Age-related blood condition counteracted with a common diabetes drug.
    Elmira Khabusheva, Margaret A Goodell.
      
    Keywords:  Ageing; Cancer; Metabolism; Stem cells
    DOI:  https://doi.org/10.1038/d41586-025-01129-5
  27. Cell Metab. 2025 Apr 09. pii: S1550-4131(25)00207-4. [Epub ahead of print]
    Spatial regulation of glucose and lipid metabolism by hepatic insulin signaling.
    Baiyu He, Kyle D Copps, Oliver Stöhr, Beikl Liu, Songhua Hu, Shakchhi Joshi, Marcia C Haigis, Morris F White, Hao Zhu, Rongya Tao.
      Hepatic insulin sensitivity is critical for systemic glucose and lipid homeostasis. The liver is spatially organized into zones in which hepatocytes express distinct metabolic enzymes; however, the functional significance of this zonation to metabolic dysregulation caused by insulin resistance is undetermined. Here, we used CreER mice to selectively disrupt insulin signaling in periportal (PP) and pericentral (PC) hepatocytes. PP-insulin resistance has been suggested to drive combined hyperglycemia and excess lipogenesis in individuals with type 2 diabetes. However, PP-insulin resistance in mice impaired lipogenesis and suppressed high-fat diet (HFD)-induced hepatosteatosis, despite elevated gluconeogenesis and insulin. In contrast, PC-insulin resistance reduced HFD-induced PC steatosis while preserving normal glucose homeostasis, in part by shifting glycolytic metabolism from the liver to the muscle. These results demonstrate distinct roles of insulin in PP versus PC hepatocytes and suggest that PC-insulin resistance might be therapeutically useful to combat hepatosteatosis without compromising glucose homeostasis.
    Keywords:  de novo lipogenesis; gluconeogenesis; hepatic glucose production; insulin resistance; insulin signaling; lipid metabolism; liver zonation; pericentral hepatocytes; periportal hepatocytes
    DOI:  https://doi.org/10.1016/j.cmet.2025.03.015
  28. Elife. 2025 Apr 15. pii: RP100535. [Epub ahead of print]13
    The extra-islet pancreas supports autoimmunity in human type 1 diabetes.
    Graham L Barlow, Christian M Schürch, Salil S Bhate, Darci J Phillips, Arabella Young, Shen Dong, Hunter A Martinez, Gernot Kaber, Nadine Nagy, Sasvath Ramachandran, Janet Meng, Eva Korpos, Jeffrey A Bluestone, Garry P Nolan, Paul L Bollyky.
      In autoimmune type 1 diabetes (T1D), immune cells infiltrate and destroy the islets of Langerhans - islands of endocrine tissue dispersed throughout the pancreas. However, the contribution of cellular programs outside islets to insulitis is unclear. Here, using CO-Detection by indEXing (CODEX) tissue imaging and cadaveric pancreas samples, we simultaneously examine islet and extra-islet inflammation in human T1D. We identify four sub-states of inflamed islets characterized by the activation profiles of CD8+T cells enriched in islets relative to the surrounding tissue. We further find that the extra-islet space of lobules with extensive islet-infiltration differs from the extra-islet space of less infiltrated areas within the same tissue section. Finally, we identify lymphoid structures away from islets enriched in CD45RA+ T cells - a population also enriched in one of the inflamed islet sub-states. Together, these data help define the coordination between islets and the extra-islet pancreas in the pathogenesis of human T1D.
    Keywords:  autoimmunity; human; immunology; inflammation; type 1 diabetes
    DOI:  https://doi.org/10.7554/eLife.100535
  29. Nat Metab. 2025 Apr 18.
    Itaconate modulates immune responses via inhibition of peroxiredoxin 5.
    Tomas Paulenda, Barbora Echalar, Lucie Potuckova, Veronika Vachova, Denis A Kleverov, Johannes Mehringer, Ekaterina Potekhina, Alex Jacoby, Devashish Sen, Chris Nelson, Rick Stegeman, Vladimir Sukhov, Danielle Kemper, Cheryl F Lichti, Nicholas J Day, Tong Zhang, Kamila Husarcikova, Monika Bambouskova, Daved H Fremont, Wei-Jun Qian, Sergej Djuranovic, Slavica Pavlovic-Djuranovic, Vsevolod V Belousov, Andrzej M Krezel, Maxim N Artyomov.
      The immunoregulatory metabolite itaconate accumulates in innate immune cells upon Toll-like receptor stimulation. In response to macrophage activation by lipopolysaccharide, itaconate inhibits inflammasome activation and boosts type I interferon signalling; however, the molecular mechanism of this immunoregulation remains unclear. Here, we show that the enhancement of type I interferon secretion by itaconate depends on the inhibition of peroxiredoxin 5 and on mitochondrial reactive oxygen species. We find that itaconate non-covalently inhibits peroxiredoxin 5, leading to the modulation of mitochondrial peroxide in activating macrophages. Through genetic manipulation, we confirm that peroxiredoxin 5 modulates type I interferon secretion in macrophages. The non-electrophilic itaconate mimetic 2-methylsuccinate inhibits peroxiredoxin 5 and phenocopies immunoregulatory action of itaconate on type I interferon and inflammasome activation, providing further support for a non-covalent inhibition of peroxiredoxin 5 by itaconate. Our work provides insight into the molecular mechanism of actions and biological rationale for the predominantly immune specification of itaconate.
    DOI:  https://doi.org/10.1038/s42255-025-01275-0
  30. J Clin Invest. 2025 Apr 15. pii: e175241. [Epub ahead of print]135(8):
    Virus-associated inflammation imprints an inflammatory profile on monocyte-derived macrophages in the human liver.
    Juan Diego Sanchez Vasquez, Shirin Nkongolo, Daniel Traum, Valentin Sotov, Samuel C Kim, Deeqa Mahamed, Aman Mehrotra, Anjali Patel, Diana Y Chen, Scott Fung, Anuj Gaggar, Jordan J Feld, Kyong-Mi Chang, Jeffrey J Wallin, Ben X Wang, Harry LA Janssen, Adam J Gehring.
      Chronic liver injury triggers the activation and recruitment of immune cells, causing antigen-independent tissue damage and liver disease progression. Tissue inflammation can reshape macrophage composition through monocyte replacement. Replacement of tissue macrophages with monocytes differentiating in an inflammatory environment can potentially imprint a phenotype that switches the liver from an immune-tolerant organ to one predisposed to tissue damage. We longitudinally sampled the liver of patients with chronic hepatitis B who had active liver inflammation and were starting antiviral therapy. Antiviral therapy suppressed viral replication and liver inflammation, which coincided with decreased myeloid activation markers. Single-cell RNA-Seq mapped peripheral inflammatory markers to a monocyte-derived macrophage population, distinct from Kupffer cells, with an inflammatory transcriptional profile. The inflammatory macrophages (iMacs) differentiated from blood monocytes and were unique from macrophage found in healthy or cirrhotic liver. iMacs retained their core transcriptional signature after inflammation resolved, indicating inflammation-mediated remodeling of the macrophage population in the human liver that may affect progressive liver disease and immunotherapy.
    Keywords:  Hepatitis; Hepatology; Immunology; Infectious disease; Macrophages
    DOI:  https://doi.org/10.1172/JCI175241
  31. Cell Rep Methods. 2025 Apr 08. pii: S2667-2375(25)00063-3. [Epub ahead of print] 101027
    Integrated analysis of transcriptional and metabolic responses to mitochondrial stress.
    Liam P Kelley, Song-Hua Hu, Sarah A Boswell, Peter K Sorger, Alison E Ringel, Marcia C Haigis.
      Mitochondrial stress arises from a variety of sources, including mutations to mitochondrial DNA, the generation of reactive oxygen species, and an insufficient supply of oxygen or fuel. Mitochondrial stress induces a range of dedicated responses that repair damage and restore mitochondrial health. However, a systematic characterization of transcriptional and metabolic signatures induced by distinct types of mitochondrial stress is lacking. Here, we defined how primary human fibroblasts respond to a panel of mitochondrial inhibitors to trigger adaptive stress responses. Using metabolomic and transcriptomic analyses, we established integrated signatures of mitochondrial stress. We developed a tool, stress quantification using integrated datasets (SQUID), to deconvolute mitochondrial stress signatures from existing datasets. Using SQUID, we profiled mitochondrial stress in The Cancer Genome Atlas (TCGA) PanCancer Atlas, identifying a signature of pyruvate import deficiency in IDH1-mutant glioma. Thus, this study defines a tool to identify specific mitochondrial stress signatures, which may be applied to a range of systems.
    Keywords:  CP: Metabolism; CP: Systems biology; cancer metabolism; integrated multi-omics; integrated stress response; metabolomics; mitochondria; mitochondrial stress response; mitochondrial unfolded protein response; stress signatures
    DOI:  https://doi.org/10.1016/j.crmeth.2025.101027
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