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Human health and neurological functions are significantly impacted by lipids, the fundamental building block of cell membranes. The central nervous system is rich in lipids, and they are evidently disturbed in neurological conditions and neurodegenerative diseases like Alzheimer's disease (AD). Alteration in lipid profile is highly linked with aging. During early onset of AD, there is a noted lipid peroxidation and modifications of fatty acids at the level of lipid rafts in the neuronal cells. AD is an age-linked neurodegenerative condition with multifaceted etiology, with combining genetic and environmental risk factors, which lacks disease-modifying therapies. While the aberrant deposition of lipids was shown in the initial studies of AD neuropathology. Clinically, lipidomic and metabolomic research have constantly exposed the changes in the levels of various lipid classes emerging in early onset of AD individuals. Also, decades of investigations have discovered multifactorial link between lipid metabolism and key AD pathogenic pathway such as amyloidogenesis, bioenergetic deficit, oxidative stress, neuroinflammation, and myelin degeneration. Herewith, we highlighted the features that impact lipid composition in neuronal cells, and the association of different lipids with known aspects of AD pathogenesis, and potential therapeutics that aim lipid crossroads.

Sequence-to-function models have been very successful in predicting gene expression, chromatin accessibility, and epigenetic marks from DNA sequences alone. However, current state-of-the-art models have a fundamental limitation: they cannot extrapolate beyond the cell types and conditions included in their training dataset. Here, we introduce Corgi, a context-aware sequence-to-function model that overcomes this limitation by integrating DNA sequence and trans-regulator expression to predict chromatin accessibility, histone modifications, and gene expression coverage, even in held-out cell types. Trained on a diverse set of bulk and single-cell sequencing datasets, Corgi achieves top performance in joint cross-sequence and cross-cell-type epigenetic track prediction. Additionally, we present an advanced model version, Corgi+, which is state-of-the-art in imputation of epigenetic tracks using only RNA-seq data. We further show that Corgi learns key cell type-specific trans-regulators in a zero-shot manner, and it can predict genomic variant effects in held-out cell types.

The plasma membrane is a ∼5nm lipid bilayer that ensheathes all living cells. Lateral heterogeneity and transbilayer asymmetry in lipid and protein distributions generate local variations in lipid packing, polarity, viscosity, lateral tension and curvature that regulate membrane protein conformation, nanoscale organisation and signalling. The composition and organisation are therefore tightly controlled and intimately coupled to cellular function. Thus, in parallel, a diverse toolkit comprising environment-sensitive small molecules, lipid-binding protein probes, hybrid chemical-genetic reporters and label-free imaging modalities has emerged to visualise membrane composition and its biophysical properties in living cells and tissues. Here, we highlight recent advances in (i) fluorescence-based readout of composition and membrane properties and (ii) mass spectrometry and vibrational imaging strategies for label-free spatial mapping of membrane composition and structure. We focus on sensing mechanisms, design principles and exemplar applications.

In RAS-mutant tumours, ERK phosphorylates the mitochondrial fission GTPase DRP1 to promote mitochondrial fission. DRP1 activity is tumour-promoting in pancreatic and other RAS-driven cancers, but its role in therapeutic resistance is unknown. We developed a panel of patient-derived pancreatic cancer cell lines resistant to the MEK inhibitor trametinib. We used immunofluorescence imaging, in vitro growth assays and orthotopic xenografts to determine the role of DRP1 in trametinib resistance. We find that trametinib-resistant cells exhibit increased expression and phosphorylation of DRP1 compared to sensitive counterparts. Quantitative analysis of mitochondrial structure reveals that mitochondria in resistant cells are morphologically distinct and relatively smaller than sensitive cells treated with trametinib. Genetic and pharmacological inhibition of both c-Myc and CDK6 are sufficient to block DRP1 phosphorylation in resistant cells, suggesting that activation of a c-Myc-CDK6 signalling axis drives reactivation of mitochondrial fission in the absence of MAPK signalling. Importantly, deletion of DRP1 leads to either growth inhibition or re-sensitisation to trametinib in resistant lines. These findings suggest DRP1 contributes to drug resistance, and that inhibition of mitochondrial fission might be a promising therapeutic strategy to combat resistance to MAPK and RAS inhibitors.

Hyperproteinemia is characterized by an unusually high plasma protein concentration (PPC). It affects both humans and animals. In this study, we used a silkworm model of hyperproteinemia to explore the mechanisms by which high PPC impairs female reproduction. Analysis of ovarian transcriptomes and qRT-PCR revealed that high PPC reduced the expression of vitellogenin (Vg) in the fat body and vitellogenin receptor (VgR) in the ovary. Further biochemical and gene expression analyses showed that high PPC decreased the titer of 20-hydroxyecdysone (20E) and the expression of key genes in the 20E-Vg/VgR signaling pathway. Exogenous 20E supplementation restored the expression of pathway components and effectively rescued female reproductive function. These findings offer new evidence for how high PPC affects female reproduction and provide a useful reference for future clinical research.

Adoptive T-cell therapy is a promising strategy for cancer immunotherapy; however, its efficacy is often limited by the immunosuppressive tumor microenvironment. γδ T cells, particularly the Vγ9Vδ2 subset, exhibit innate-like cytotoxicity and are emerging candidates for adoptive immunotherapy. Pemetrexed, an antifolate chemotherapeutic agent, has documented immunomodulatory effects in αβ T-cell settings; however, its impact on γδ T-cell antitumor responses remains insufficiently defined. Here, Vγ9Vδ2 T cells were isolated and expanded from healthy-donor peripheral blood mononuclear cells (PMBCs) and co-cultured with non-small cell lung cancer (NSCLC) cells with or without pemetrexed pretreatment. Pemetrexed significantly enhanced γδ T cell-mediated cytotoxicity compared with either treatment alone. Mechanistically, pemetrexed increased the expression of NKG2D ligands, including MHC class I chain-related proteins A/B (MICA/B) and UL16-binding proteins (ULBPs), through the ataxia-telangiectasia mutated (ATM)-stimulator of interferon genes (STING)-nuclear factor-κB (NF-κB) signaling axis. ATM activation triggered cyclic GMP-AMP synthase-independent STING signaling and preferentially activated NF-κB rather than interferon regulatory factor 3 (IRF3), thereby promoting transcriptional upregulation of NKG2D ligands and improving tumor recognition by γδ T cells. Consistent with the cell-line findings, pemetrexed increased MICA/B and ULBP2/5/6 expression in NSCLC patient-derived organoids. Furthermore, in an in vivo NSCLC animal model, combined pemetrexed and adoptive γδ T-cell therapy suppressed tumor growth more effectively than either treatment alone and was accompanied by increased NKG2D ligand expression. Collectively, these findings reveal a tumor-sensitizing mechanism by which pemetrexed potentiates γδ T-cell antitumor function and support combining pemetrexed with γδ T cell-based immunotherapy for NSCLC.

Proper oropharyngeal function is essential for suckling, feeding, and speech, and relies on the coordinated development of the palate, oropharyngeal musculature, and the cranial nerves that control them. Disruption of this integration leads to severe neonatal complications. However, how neuromuscular architecture is developmentally coordinated to support oropharyngeal function remains unclear. Using single-cell and spatial transcriptomics, we identify trigeminal nerve-derived GDF11 as a crucial regulator of soft palatal muscle architecture that acts through cranial neural crest-derived perimysial cells and is mediated by Akt-FoxO1-Thbs3 signaling to establish muscle structural integrity and bilateral continuity. To assess its functional relevance in vivo, we employ a battery of physiological assays to evaluate oropharyngeal function in neonatal mice and find that sensory neuron-specific Gdf11 deletion recapitulates soft palatal deformities and associated oropharyngeal dysfunction observed in individuals carrying GDF11 mutations, including impaired suckling, reduced oropharyngeal motor efficacy, and abnormal vocalizations. Pharmacological activation of AKT partially restores soft palatal muscle organization and ameliorates associated physiological deficits in Gdf11 mutant mice. Collectively, these findings demonstrate that sensory nerve-derived trophic signaling is indispensable for coordinated oropharyngeal morphogenesis and function, and establish a pre-clinical framework for the therapeutic approach targeting neuromuscular integration in congenital oropharyngeal disorders.

Triphenyltin (TPT), a widespread organotin pollutant with significant ecological risks, has been reported to induce vascular injury, though the underlying mechanisms remain unclear. We hypothesized that TPT exposure impairs vascular development in zebrafish larvae through mitochondrial dysfunction and oxidative stress, leading to endothelial cell death and vascular structural defects. Here, we used transgenic zebrafish, imaging, histology, mitochondrial assays, qPCR and transcriptomics to assess TPT-induced vascular toxicity across morphological, functional and molecular levels. In this study, zebrafish larvae were exposed to TPT from 24 to 96&#x202f;h post-fertilization at 12.5, 25, and 50&#x202f;nM, corresponding to approximately 1/5, 1/3 and 3/4 of the 96-h LC50 (68&#x202f;nM). The lowest concentration is within environmentally relevant ranges. TPT exposure caused pronounced vascular damage, as visualized using transgenic live imaging lines. At 50&#x202f;nM TPT, heart rate decreased by 32%, blood flow velocity decreased by 58%, and intersegmental vessel length decreased by 45% (all p&#x202f;<&#x202f;0.01 vs. control). At the cellular level, increased endothelial cell death was evident. Mechanistically, TPT exposure led to mitochondrial dysfunction, as indicated by reductions in mitochondrial content, and upregulated expression of pro-apoptotic genes such as bax and caspase-3. Contrary to our initial hypothesis, several VEGF/Notch signaling components (e.g., vegfaa, notch1) were significantly upregulated, which may represent a compensatory response rather than direct pathway suppression. All experiments included at least three biological replicates. Statistical significance was assessed by one-way ANOVA with Tukey's post-hoc test (p&#x202f;<&#x202f;0.05). Collectively, these findings demonstrated that TPT exposure induces vascular developmental toxicity in zebrafish associated with mitochondrial dysfunction and cell death, along with dysregulated expression of VEGF/Notch pathway transcripts, and underscore the importance of further research on the ecological and health risks of organotin pollutants.

A catalyst-free visible-light-induced protocol for the C4-selective C-H arylation of pyrimidine derivatives has been developed using arylazo sulfones as aryl radical precursors. Under mild conditions and without external photocatalysts or transition metals, a broad range of arylated pyrimidines were obtained in moderate to excellent yields. Mechanistic studies, including radical trapping experiments and light-control tests, support a visible-light-triggered radical pathway. Selected compounds exhibited promising antiproliferative activities against A549 and MCF-7 cell lines.

Improvements in pediatric cancer survival has increased the risk of long-term, treatment-related complications, including persistent skeletal muscle deficits. These impairments are often interpreted through mechanisms derived from adult models, which emphasize mitochondrial dysfunction and metabolic stress. However, pediatric cancer therapies are delivered during periods of active growth, when skeletal muscle expansion depends on satellite cell-mediated myonuclear accretion and establishment of the adult stem cell pool. In this Perspective, we propose that radiation and chemotherapy disrupt satellite cell-dependent processes during development, leading to impaired muscle growth and long-term functional deficits. Evidence from radiation models demonstrates reduced satellite cell abundance, impaired regeneration, and persistent structural abnormalities throughout pediatric development, while emerging chemotherapy data indicate alterations in myogenic regulatory programs and reduced satellite cell number, with limited overlap with adult responses. Together, these findings support a framework in which pediatric cancer therapies impair developmental muscle growth rather than solely inducing atrophy. Targeting satellite cells may represent a therapeutic strategy to restore muscle development and improve long-term outcomes in pediatric cancer survivors.

Accumulation of neurofibrillary tangles (NFTs) in the neuronal cells is the predominant features of Alzheimer's diseases (AD) and other Tauopathies. Studies on molecular mechanism of human neurodegenerative disease shows that the substantial posttranslational modifications (PTMs) of Tau is essential for the conversion of monomeric soluble form into the aberrant insoluble aggregates in pathological condition. During pathogenesis of AD, Tau phosphorylation state is altered by the activation of various kinases and phosphates and eventually Tau become hyperphosphorylated. Hyperphosphorylated Tau detach from microtubules and aggregate intracellularly in affected neurons. This pathological Tau invades the subcellular organelles including mitochondria and leads to degeneration and cell death. Ageing is the crucial factor causing alteration in brain including, structural and functional role of Tau. Pathological Tau disrupts signaling cascades of mitochondria, energy-associated mechanism and this causes the elevation of oxidative stress in the neurons. Furthermore, hyperphosphorylated Tau also inhibits the mitophagy and autophagy-lysosomal pathway, resulting in the buildup of dysfunctional mitochondria in the affected neurons. This review highlights the major signaling cascades involved in Tau PTMs and its interlinked role in mitochondrial damage in aging population in AD.

Peritoneal fibrosis (PF) is a major cause of technique failure in long-term peritoneal dialysis (PD) patients, driven by a chronic microinflammatory state. While T-cell activation is implicated, the role of soluble programmed death-1 (sPD-1), primarily derived from activated T cells, in PF pathogenesis remains elusive. We initially analyzed serum sPD-1 levels in PD patients and employed a mice PF model induced by high-glucose dialysate and lipopolysaccharide (LPS). The functional impact of sPD-1 on the progression of PF was assessed through the administration of a PD-L1 fusion protein, or engineered exosomes designed to adsorb sPD-1. Serum sPD-1 levels were significantly elevated in long-term PD patients and were positively correlated with dialysis duration and markers of fibrosis, but inversely correlating with peritoneal function. In mice, exogenous sPD-1 exacerbated PF, whereas blockade with a PD-L1 fusion protein or sPD-1-adsorbing engineered exosomes markedly attenuated fibrosis, reduced T-cell infiltration, and preserved peritoneal function. Mechanistically, sPD-1 bound to PD-L1 on PMCs, triggering clathrin-mediated endocytosis. This interaction diverted PD-L1 from the lysosomal degradation pathway towards the Rab11-positive recycling endosome pathway, resulting in sustained upregulation of surface PD-L1 expression. This aberrant PD-L1 recycling activated pro-fibrotic signaling, culminating in mesothelial-to-mesenchymal transition (MMT). sPD-1 is a pivotal mediator linking peritoneal microinflammation to fibrosis by modulating the endocytic fate of PD-L1 in mesothelial cells. Targeting sPD-1, particularly using engineered exosomes or a PD-L1 fusion protein, represents a promising therapeutic strategy for preventing and treating peritoneal fibrosis.

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With the widespread application of lithium-ion batteries (LIBs) globally, lithium nickel cobalt manganese oxide (LiNi0.5Co0.2Mn0.3O2, NCM523) has emerged, as a core cathode material, raising growing concerns over its prominent risk of respiratory exposure throughout its entire life cycle. This study established a mouse exposure model via intratracheal instillation to systematically explore the pulmonary toxicity and underlying molecular mechanisms of NCM523 by combining spatial metabolomics, single-cell RNA sequencing (scRNA-seq), and other complementary techniques. The results demonstrated that NCM523 exposure led to significant deposition of Ni, Co, Mn, and Li within mouse lung tissues, inducing restrictive ventilatory dysfunction and pulmonary fibrosis. Spatial metabolomics revealed a significant reduction in essential phospholipids, such as phosphatidylcholine in alveolar injury regions, alongside enrichment of metabolites related to fibroblast activation within fibrotic regions. Meanwhile, scRNA-seq and experimental validation confirmed the induction of the epithelial-mesenchymal transition (EMT) phenotype both in vivo and in vitro. Mechanistically, NCM523 preferentially accumulated as particulates on the plasma membranes of mouse alveolar type II epithelial cells, physically activating the mechanosensitive ion channel Piezo1. This activation triggered calcium influx and endoplasmic reticulum stress (ERS), thereby reducing phospholipid levels and ultimately inducing EMT. Pharmacological inhibition of Piezo1 by GsMTx4 effectively reversed the aforementioned pathological abnormalities, while the agonist Yoda1 exacerbated the damage. And inhibition of Piezo1 could alleviate NCM523-induced pulmonary fibrosis. This study highlighted the critical role of the particulate physical properties in lung injury, clarified Piezo1-mediated mechanotransduction as a central pathway in NCM523-induced pulmonary fibrosis, and provided an important basis for understanding LIBs-related pulmonary fibrosis risks and developing targeted intervention strategies.

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Loss of filaggrin (FLG) function impairs skin barrier formation and contributes to common inflammatory skin diseases. In this study, we established a FLG knockout human induced pluripotent stem cell (iPSC) line based on KOLF2.1&#xa0;J using CRISPR/Cas12a (Cpf1)-mediated genome editing. A guide RNA targeting exon 2 introduced a homozygous mutation, which was confirmed by sequencing. The edited cells maintained typical pluripotent stem cell morphology, expressed key undifferentiated markers, and retained the ability to differentiate into all three germ layers. Karyotype and copy number variation (CNV) analyses confirmed genomic stability and parental origin; the cells were free of mycoplasma. This cell line enables studies of FLG-associated skin biology and pathology.

Cell free RNA (cfRNA) based liquid biopsy is pushing noninvasive diagnostics forward, moving the field from a static view focused on genomics into a more dynamic space centered on functional transcriptomics. Circulating tumor DNA (ctDNA) mainly tells us about genetic alterations, but cfRNA provides a distinct informational dimension by capturing gene expression as it happens, along with splicing changes, non-coding regulation, and post-transcriptional modifications. This yields a more functional and comprehensive picture of disease biology. This review systematically examines the molecular features of cfRNA, contemporary analytical technologies, and clinical applications spanning early cancer detection, molecular subtyping, and prediction of pregnancy complications. Emerging dimensions including fragmentomics, epitranscriptomics, and microbial-derived cfRNA are also examined. Current challenges around standardization, sensitivity, and clinical validation are addressed. With advances in multi-omics integration and artificial intelligence, cfRNA has substantial potential to evolve from a supplementary biomarker into a core technology for early disease detection, longitudinal monitoring, and personalized treatment. The goal of this review is to delineate the current state of the field, identify key obstacles, and outline pathways through which cfRNA may achieve routine clinical implementation.

Spike antigenemia has been proposed as a mechanism underlying post-COVID condition (PCC). We determined whether persistent free SARS-CoV-2 Spike or Nucleocapsid antigenemia is associated with post-COVID condition (PCC) or systemic inflammation. As a secondary methodological aim, we evaluated whether dithiothreitol (DTT) treatment reliably unmasks antibody-bound Spike. Within the ORCHESTRA project, we quantified free Spike and Nucleocapsid in 200 participants (112 PCC, 58 non-PCC and 30 pre-pandemic controls), analysing 576 samples collected during acute infection (n=99) and at 3, 6, 12, and 18 months post-infection (n=447). Correlations between free Spike and proinflammatory markers were assessed. The effect of 10 mM DTT on Spike detectability was validated prior to analysis. During acute infection, Nucleocapsid was detectable in nearly all participants (n=98/99), and Spike in 15/99 (15.2%). Low-level antigen persisted in a subset of participants up to 18 months, however, neither free Spike nor Nucleocapsid differed between PCC and controls or were independently associated with PCC (Spike: OR, 0.99; 95% CI, 0.55-1.78; Nucleocapsid: OR, 0.52; 95% CI, 0.14-2.03). At 3-6 months post-infection, free Spike correlated with proinflammatory cytokines, with stronger associations in PCC than controls (all p<0.05). Methodologically, DTT reduced recombinant Spike detectability by 90.9&#xb1;0.7% at 10 mM (p<0.001) yet increased measured plasma signal 2.6&#xb1;2.7-fold in pandemic samples and 5.5&#xb1;2.4-fold in pre-pandemic controls (p<0.001), indicating non-specific assay artifact rather than recovery of antibody-bound antigen. Low-level systemic antigen persistence occurs in a subset of individuals but does not differentiate PCC from recovered controls. Early convalescent Spike-cytokine correlations likely reflect transient, host-specific immune activation rather than a persistent viral driver. Furthermore, DTT does not recover true immune-complexed antigen but generates non-specific assay artifacts. These data argue against persistent circulating antigenemia as a primary, generalizable driver of PCC, highlighting the need for cautious biomarker interpretation.

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a biodegradable copolymer whose mechanical properties can be tuned by the 3-hydroxyhexanoate (3HHx) fraction. However, current industrial production largely relies on established hosts and plant oil-based feedstocks. Here, we developed Rhodobacter capsulatus SB1003 as a new PHBH-producing platform by focusing on the two key determinants of copolymer formation: polyhydroxyalkanoate (PHA) synthase substrate specificity and intracellular monomer supply. A PHA synthase with broad-substrate specificity was integrated into the native phaC locus to generate a heterologous phaC strain. All PHA production experiments were performed under anaerobic photoheterotrophic conditions in 8-mL screw-cap tubes containing 7.6 mL of medium and illuminated with continuous white light. During butyrate cultivation under these conditions, the engineered strain accumulated polymer up to 41.5% of cell dry weight and incorporated detectable 3HHx, whereas the wild type showed no 3HHx incorporation. To increase 3HHx-CoA availability from butyrate, we introduced C4-to-C6 precursor-supply modules involving &#x3b2;-ketothiolase (BktB)/&#x3b2;-ketoacyl-CoA reductase (PhaB) and crotonyl-CoA carboxylase/reductase (Ccr)/ethylmalonyl-CoA decarboxylase (Emd), but these modifications led to only marginal improvements in the 3HHx fraction. In contrast, supplying C6 or longer fatty acids under the same conditions markedly increased 3HHx incorporation; cultivation on hexanoate yielded PHBH containing 32.4 mol% 3HHx. Collectively, this study demonstrates PHBH biosynthesis in R. capsulatus and indicates that limited 3HHx-CoA supply rather than polymerization capacity is the primary bottleneck, providing a foundation for further pathway and host optimization toward flexible PHBH production from diverse substrates.