The Polycomb group (PcG) protein chromobox 8 (CBX8) is the subunit of Polycomb repressive complex 1 (PRC1) and recognizes the trimethylation of histone H3 on Lysine 27 (H3K27me3), and coordinates with PRC2 complex to function as an epigenetic gene silencer. CBX8 plays a key role in cell proliferation, stem cell biology, cell senescence, and cancer development. However, the post-translational modifications of CBX8 remain poorly understood. Here, we report that protein kinase D1 (PKD1) interacts and phosphorylates CBX8 at Thr234 and Ser256 /311 residues. PKD1-mediated CBX8 phosphorylation at Thr234 reduced its expression level by promoting its ubiquitination-mediated degradation, whereas Ser256/311 phosphorylation decreased CBX8 binding to other PRC1 components BMI1 and RING1A. Overall, CBX8 phosphorylation by PKD1 impaired PRC1 complex integrity and activity, mitigated H2AK119ub1 level, caused the upregulation of multiple target genes repressed by CBX8, and decreased CBX8, H2AK119ub1, and H3K27me3 enrichment at INK4A/ARF locus, thereby derepressing p16INK4A and facilitating cellular senescence. Collectively, these results suggest that PKD1-mediated CBX8 phosphorylation at T234 and S256/311 is a key mechanism governing CBX8 function, including cell senescence. © 2025. The Author(s), under exclusive licence to Springer Nature Limited.

The insulin-like growth factor-1 (IGF-1) signaling pathway is known as a potent aging modifier, disruption of which consistently associates with lifespan extension across diverse species. Despite this established association, the mechanisms by which IGF-1 signaling modulates organ aging remain poorly understood. In this study, we assessed age-related changes in IGF-1 expression across multiple organs in mice and identified a more prominent increase in skin IGF-1 levels with aging-a phenomenon also observed in human skin. To explore the consequences of elevated IGF-1, we developed transgenic mice ectopically expressing human IGF-1 in the epidermis, driven by the bovine keratin 5 promoter (IGF-1 Tg). These mice exhibited premature aging of hair follicles, as evidenced by accelerated hair graying and loss. Single-cell RNA sequencing analyses of dorsal skin highlighted an upsurge in cellular senescence markers and the senescence-associated secretory phenotype (SASP) in hair follicle stem cells (HFSCs), alongside a decline in hair growth and HFSC exhaustion. Our findings indicate that excessive IGF-1 triggers HFSC senescence, thereby disrupting hair follicle homeostasis. Remarkably, interventions in IGF-1 signaling via downstream mechanisms-specifically blocking Ac-p53 activation via SIRT1 overexpression or senolytic treatment for senescent cell clearance, or reducing IGF-1 through dietary restriction-significantly reduced senescence markers, mitigated premature hair follicle aging phenotypes, and restored the stem cell pool. Our findings provide fundamental insights into the biological processes of hair aging and highlight the therapeutic promise of targeted interventions to rejuvenate aged HFSCs and promote hair follicle health. © 2025 The Author(s). Aging Cell published by Anatomical Society and John Wiley & Sons Ltd.

The National Genomics Data Center (NGDC), which is a part of the China National Center for Bioinformation (CNCB), offers a comprehensive suite of database resources to support the global scientific community. Amidst the unprecedented accumulation of multi-omics data, CNCB-NGDC is committed to continually evolving and updating its core database resources through big data archiving, integrative analysis and value-added curation. Over the past year, CNCB-NGDC has expanded its collaborations with international databases and established new subcenters focusing on biodiversity, traditional Chinese medicine and tumor genetics. Substantial efforts have been made toward encompassing a broad spectrum of multi-omics data, developing innovative resources and enhancing existing resources. Notably, new resources have been developed for single-cell omics (scTWAS Atlas), genome and variation (VDGE), health and disease (CVD Atlas, CPMKG, Immunosenescence Inventory, HemAtlas, Cyclicpepedia, IDeAS), biodiversity and biosynthesis (RefMetaPlant, MASH-Ocean) and research tools (CCLHunter). All resources and services are publicly accessible at https://ngdc.cncb.ac.cn. © The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.

DEAD-box helicase 17 (DDX17) is a typical member of the DEAD-box family with transcriptional cofactor activity. Although DDX17 is abundantly expressed in the myocardium, its role in heart is not fully understood. We generated cardiomyocyte-specific Ddx17-knockout mice (Ddx17-cKO), cardiomyocyte-specific Ddx17 transgenic mice (Ddx17-Tg), and various models of cardiomyocyte injury and heart failure (HF). DDX17 is downregulated in the myocardium of mouse models of heart failure and cardiomyocyte injury. Cardiomyocyte-specific knockout of Ddx17 promotes autophagic flux blockage and cardiomyocyte apoptosis, leading to progressive cardiac dysfunction, maladaptive remodeling and progression to heart failure. Restoration of DDX17 expression in cardiomyocytes protects cardiac function under pathological conditions. Further studies showed that DDX17 can bind to the transcriptional repressor B-cell lymphoma 6 (BCL6) and inhibit the expression of dynamin-related protein 1 (DRP1). When DDX17 expression is reduced, transcriptional repression of BCL6 is attenuated, leading to increased DRP1 expression and mitochondrial fission, which in turn leads to impaired mitochondrial homeostasis and heart failure. We also investigated the correlation of DDX17 expression with cardiac function and DRP1 expression in myocardial biopsy samples from patients with heart failure. These findings suggest that DDX17 protects cardiac function by promoting mitochondrial homeostasis through the BCL6-DRP1 pathway in heart failure.

ObjectiveIn December 2019, a novel pneumonia associated with the 2019 coronavirus emerged unexpectedly. However, limited data exist on the effects of COVID-19 on ACTH and cortisol levels. To address this gap in knowledge, we conducted a meta-analysis of published studies on the relationship between COVID-19 patients and their ACTH and cortisol levels.MethodsWe conducted a thorough search of the PubMed, Embase, Cochrane Library, and Web of Science databases up until May 2023. We assessed the relevance of each study we found, specifically looking for studies that reported on ACTH and cortisol levels in COVID-19 patients. We calculated weighted mean differences (WMD) and 95% confidence intervals (CI) to investigate the relationship between ACTH and cortisol levels in COVID-19 patients. We evaluated the quality of each study using the Newcastle Ottawa scale (NOS), and we assessed publication bias using Begg's rank correlation test, Egger's test, and funnel plot. We conducted our meta-analysis using the Stata 12.0 (Stata Corporation, TX).ResultsOur search yielded nine studies that met our inclusion criteria, which included a total of 440 COVID-19 patients and 474 controls, with data up to May 2023. Seven of these studies reported on ACTH levels, and six studies reported on cortisol levels. Our findings revealed that COVID-19 patients had significantly higher levels of cortisol compared to controls (WMD 3.46 (95% CI 2.29 to 4.62)). However, there was no significant difference in ACTH levels between COVID-19 patients and controls (WMD 1.58 (95% CI -5.79 to 8.94)).ConclusionsThis meta-analysis indicates a potential relationship between elevated cortisol levels and COVID-19 infection. However, more well-designed, adequately powered, randomized controlled trial will be needed to assess the use of cortisol in patients with COVID-19 infection.

Age-associated hypercoagulability is accompanied by the increase of plasma levels of some coagulation factors including fibrinogen which may contribute to the increased risk of cardiovascular, cerebrovascular, and thrombotic diseases in elderly people. However, the underlying mechanism of increased plasma fibrinogen concentration during aging is still elusive. GRSF1 belongs to the heterogeneous nuclear ribonucleoproteins F/H (hnRNP F/H) subfamily. Here, we report that GRSF1 attenuates hypercoagulability via negative modulation of fibrinogen expression. We demonstrated that GRSF1 negatively regulated fibrinogen expression at both mRNA and protein levels. GRSF1 directly interacted with the coding region (CDS) of FGA, FGB, and FGG mRNAs, and decreased their stability thus mitigating fibrinogen expression. We further identified that only a few G-tracts within the Fib C domain of FGA, FGB, and FGG CDS and the qRRM2 domain of GRSF1 were required for their interaction. Moreover, we confirmed hypercoagulability and the decrease of GRSF1 expression level during mice aging. Functionally, GRSF1 overexpression in old mice liver decreased fibrinogen plasma level, reduced hypercoagulability, and mitigated blood coagulation activity, whereas GRSF1 knockdown in young mice liver increased fibrinogen plasma level and promoted blood coagulation activity. Collectively, our findings unveil a novel posttranscriptional regulation of fibrinogen by GRSF1 and uncover a critical role of GRSF1 in regulating blood coagulation activity. © 2023. The Author(s).

Mesenchymal stromal cells (MSCs) derived from human embryonic stem cells (hESCs) are a desirable cell source for cell therapy owing to their capacity to be produced stably and homogeneously in large quantities. However, a scalable culture system for hPSC-derived MSCs is urgently needed to meet the cell quantity and quality requirements of practical clinical applications. In this study, we developed a new microcarrier with hyaluronic acid (HA) as the core material, which allowed scalable serum-free suspension culture of hESC-derived MSCs (IMRCs). We used optimal microcarriers with a coating collagen concentration of 100 ​μg/mL or concave-structured surface (cHAMCs) for IMRC amplification in a stirred bioreactor, expanding IMRCs within six days with the highest yield of over one million cells per milliliter. In addition, the harvested cells exhibited high viability, immunomodulatory and regenerative therapeutic promise comparable to monolayer cultured MSCs while showing more increased secretion of extracellular matrix (ECM), particularly collagen-related proteins. In summary, we have established a scalable culture system for hESC-MSCs, providing novel approaches for future cell therapies. © 2023

Exhausted T (TEX) cells are main immunotherapy targets in cancer, but it lacks a general identification method to characterize TEX cell in disease. To assess the characterization of TEX cell, we extract signature of TEX cell from large cancer and chronic infection cohorts. Based on single-cell transcriptomes, a systematic T cell exhaustion prediction (TEXP) model is designed to define TEX cell in cancer and chronic infection. We then prioritize 42 marker genes, including HAVCR2, PDCD1, TOX, TIGIT and LAG3, which are associated with T cell exhaustion. TEXP could identify high TEX and low TEX subtypes in pan-cancer of TCGA. The high TEX subtypes are characterized by high immune score, immune cell infil-tration, high expression of TEX marker genes and poor prognosis. In summary, TEXP and marker genes provide a resource for understanding the function of TEX cell, with implications for immune prediction and immunotherapy in chronic infection and cancer.

The authors characterized m(6)A dynamics in primate tissue aging and revealed a new role for the METTL3-m(6)A-NPNT axis in maintaining skeletal muscle homeostasis, thereby providing insight into the epitranscriptomic machinery underlying primate aging.How N-6-methyladenosine (m(6)A), the most abundant mRNA modification, contributes to primate tissue homeostasis and physiological aging remains elusive. Here, we characterize the m(6)A epitranscriptome across the liver, heart and skeletal muscle in young and old nonhuman primates. Our data reveal a positive correlation between m(6)A modifications and gene expression homeostasis across tissues as well as tissue-type-specific aging-associated m(6)A dynamics. Among these tissues, skeletal muscle is the most susceptible to m(6)A loss in aging and shows a reduction in the m(6)A methyltransferase METTL3. We further show that METTL3 deficiency in human pluripotent stem cell-derived myotubes leads to senescence and apoptosis, and identify NPNT as a key element downstream of METTL3 involved in myotube homeostasis, whose expression and m(6)A levels are both decreased in senescent myotubes. Our study provides a resource for elucidating m(6)A-mediated mechanisms of tissue aging and reveals a METTL3-m(6)A-NPNT axis counteracting aging-associated skeletal muscle degeneration.

IFT-A plays crucial roles in bidirectional ciliary transport, vital for cilia biogenesis and signaling. Here, Ma et al. report the IFT-A structure in two distinct states and unveil the assembly mechanism of IFT-A into the anterograde train.Intraflagellar transport (IFT) trains, the polymers composed of two multi-subunit complexes, IFT-A and IFT-B, carry out bidirectional intracellular transport in cilia, vital for cilia biogenesis and signaling. IFT-A plays crucial roles in the ciliary import of membrane proteins and the retrograde cargo trafficking. However, the molecular architecture of IFT-A and the assembly mechanism of the IFT-A into the IFT trains in vivo remains elusive. Here, we report the cryo-electron microscopic structures of the IFT-A complex from protozoa Tetrahymena thermophila. We find that IFT-A complexes present two distinct, elongated and folded states. Remarkably, comparison with the in situ cryo-electron tomography structure of the anterograde IFT train unveils a series of adjustments of the flexible arms in apo IFT-A when incorporated into the anterograde train. Our results provide an atomic-resolution model for the IFT-A complex and valuable insights into the assembly mechanism of anterograde IFT trains.