参考文献

Increasing shreds of evidence suggest that neurogenic-to-gliogenic shift may be critical to the abnormal neurodevelopment observed in individuals with Down syndrome (DS). REST,the Repressor Element-1 Silencing Transcription factor,regulates the differentiation and development of neural cells. Downregulation of REST may lead to defects in post-differentiation neuronal morphology in the brain of the DS fetal. This study aims to elucidate the role of REST in DS-derived NPCs using bioinformatics analyses and laboratory validations. We identified and validated vital REST-targeted DEGs: CD44,TGFB1,FN1,ITGB1,and COL1A1. Interestingly,these genes are involved in neurogenesis and gliogenesis in DS-derived NPCs. Furthermore,we identified nuclear REST loss and the neuroblast marker,DCX,was downregulated in DS human trisomic induced pluripotent stem cells (hiPSCs)-derived NPCs,whereas the glioblast marker,NFIA,was upregulated. Our findings indicate that the loss of REST is critical in the neurogenic-to-gliogenic shift observed in DS-derived NPCs. REST and its target genes may collectively regulate the NPC phenotype.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-87314-y. View Publication

Peroxisomes are eukaryotic organelles that are essential for multiple metabolic pathways,including fatty acid oxidation,degradation of amino acids,and biosynthesis of ether lipids. Consequently,peroxisome dysfunction leads to pediatric-onset neurodegenerative conditions,including Peroxisome Biogenesis Disorders (PBD). Due to the dynamic,tissue-specific,and context-dependent nature of their biogenesis and function,live cell imaging of peroxisomes is essential for studying peroxisome regulation,as well as for the diagnosis of PBD-linked abnormalities. However,the peroxisomal imaging toolkit is lacking in many respects,with no reporters for substrate import,nor cell-permeable probes that could stain dysfunctional peroxisomes. Here we report that the BODIPY-C12 fluorescent fatty acid probe stains functional and dysfunctional peroxisomes in live mammalian cells. We then go on to improve BODIPY-C12,generating peroxisome-specific reagents,PeroxiSPY650 and PeroxiSPY555. These probes combine high peroxisome specificity,bright fluorescence in the red and far-red spectrum,and fast non-cytotoxic staining,making them ideal tools for live cell,whole organism,or tissue imaging of peroxisomes. Finally,we demonstrate that PeroxiSPY enables diagnosis of peroxisome abnormalities in the PBD CRISPR/Cas9 cell models and patient-derived cell lines. The array of tools to image peroxisome regulation is still limited. Here,the authors develop improved fatty acid-based probes with high peroxisome specificity and bright fluorescence in the red/far-red spectrum,which makes them ideal to study peroxisomes in live cells and whole organisms. View Publication

Somatic cell reprogramming into human induced pluripotent stem cells entails significant intracellular changes,including modifications in mitochondrial metabolism and a decrease in mitochondrial DNA copy number. However,the mechanisms underlying this decrease in mitochondrial DNA copy number during reprogramming remain unclear. Here we aimed to elucidate these underlying mechanisms. Through a meta-analysis of several RNA sequencing datasets,we identified genes responsible for the decrease in mitochondrial DNA. We investigated the functions of these identified genes and assessed their regulatory mechanisms. In particular,the expression of the thymidine kinase 2 gene (TK2),located in the mitochondria and required for mitochondrial DNA synthesis,is decreased in human pluripotent stem cells as compared with its expression in somatic cells. TK2 was significantly downregulated during reprogramming and markedly upregulated during differentiation. Collectively,this decrease in TK2 levels induces a decrease in mitochondrial DNA copy number and contributes to shaping the metabolic characteristics of human pluripotent stem cells. However,contrary to our expectations,treatment with a TK2 inhibitor impaired somatic cell reprogramming. These results suggest that decreased TK2 expression may result from metabolic conversion during somatic cell reprogramming. Mitochondrial DNA loss linked to stem cell reprogrammingInduced pluripotent stem (iPS) cells are special cells created by reprogramming regular body cells. Researchers explored how these cells change their energy production methods during reprogramming. The study focused on a protein called thymidine kinase 2 (TK2),which is important for maintaining mitochondrial DNA (mtDNA). Mitochondria are the cell’s powerhouses,and their DNA is crucial for energy production. Researchers used human cell lines to study how TK2 affects mtDNA during reprogramming. They found that,as cells become iPS cells,TK2 levels drop,leading to reduced mtDNA and a shift in energy production from oxidative phosphorylation to glycolysis. Results suggest that reducing TK2 and mtDNA is key for cells to gain pluripotency. This shift helps support the rapid growth and development of iPS cells. Understanding this process could improve stem cell therapies and regenerative medicine in the future.This summary was initially drafted using artificial intelligence,then revised and fact-checked by the author. View Publication

The angiotensin-converting enzyme 2 (ACE2) is a primary cell surface viral binding receptor for SARS-CoV-2,so finding new regulatory molecules to modulate ACE2 expression levels is a promising strategy against COVID-19. In the current study,we utilized islet organoids derived from human embryonic stem cells (hESCs),animal models and COVID-19 patients to discover that fibroblast growth factor 7 (FGF7) enhances ACE2 expression within the islets,facilitating SARS-CoV-2 infection and resulting in impaired insulin secretion. Using hESC-derived islet organoids,we demonstrated that FGF7 interacts with FGF receptor 2 (FGFR2) and FGFR1 to upregulate ACE2 expression predominantly in ? cells. This upregulation increases both insulin secretion and susceptibility of ? cells to SARS-CoV-2 infection. Inhibiting FGFR counteracts the FGF7-induced ACE2 upregulation,subsequently reducing viral infection and replication in the islets. Furthermore,retrospective clinical data revealed that diabetic patients with severe COVID-19 symptoms exhibited elevated serum FGF7 levels compared to those with mild symptoms. Finally,animal experiments indicated that SARS-CoV-2 infection increased pancreatic FGF7 levels,resulting in a reduction of insulin concentrations in situ. Taken together,our research offers a potential regulatory strategy for ACE2 by controlling FGF7,thereby protecting islets from SARS-CoV-2 infection and preventing the progression of diabetes in the context of COVID-19. View Publication

Neurogenin3 (NEUROG3) is required for endocrine lineage formation of the pancreas and intestine. Patients with NEUROG3 mutations are born with congenital malabsorptive diarrhea due to complete loss of enteroendocrine cells,whereas endocrine pancreas development varies in an allele-specific manner. These findings suggest a context-dependent requirement for NEUROG3 in pancreas versus intestine. We utilized human tissue differentiated from NEUROG3-/- pluripotent stem cells for functional analyses. Most disease-associated alleles had hypomorphic or null phenotype in both tissues,whereas the S171fsX68 mutation had reduced activity in the pancreas but largely null in the intestine. Biochemical studies revealed NEUROG3 variants have distinct molecular defects with altered protein stability,DNA binding,and gene transcription. Moreover,NEUROG3 was highly unstable in the intestinal epithelium,explaining the enhanced sensitivity of intestinal defects relative to the pancreas. These studies emphasize that studies of human mutations in the endogenous tissue context may be required to assess structure-function relationships. View Publication

Graphene quantum dots (GQDs) have gained significant attention in various biomedical applications. The physicochemical properties of these nanoparticles,including toxic effects,are largely determined by their surface modifications. Previous studies have demonstrated high in vitro cytotoxicity of the hydroxylated GQDs (OH-GQDs). The focus of this study was on the intestinal toxicity of OH-GQDs. Briefly,C57BL/6J mice were given daily oral gavage of 0.05,0.5 or 5 mg/kg OH-GQD for 7 days,and the indices of intestinal damage were evaluated. Higher doses of the OH-GQDs caused significant intestinal injuries,such as enhanced intestinal permeability,shortened villi and crypt loss. The number of Lgr5+ intestinal stem cells also decreased dramatically upon OH-GQDs exposure,which also inhibited the Ki67+ proliferative progenitor cells. In addition,an increased number of crypt cells harboring the oxidized DNA base 8-OHdG and $\gamma$H2AX foci were also detected in the intestines of OH-GQD-treated mice. Mechanistically,the OH-GQDs up-regulated both total and phosphorylated p53. Consistent with this,the average number of TUNEL+ and cleaved caspase-3+ apoptotic intestinal epithelial cells were significantly increased after OH-GQDs treatment. Finally,a 3-dimensional organoid culture was established using isolated crypts,and OH-GQDs treatment significantly reduced the size of the surviving intestinal organoids. Taken together,the intestinal toxicity of the OH-GQDs should be taken into account during biomedical applications. View Publication

Shiga toxigenic Escherichia coli (STEC) are responsible for a worldwide foodborne disease,which is characterized by severe bloody diarrhea and hemolytic uremic syndrome (HUS). Subtilase cytotoxin (SubAB) is a novel AB5 toxin,which is produced by Locus for Enterocyte Effacement (LEE)-negative STEC. Cleavage of the BiP protein by SubAB induces endoplasmic reticulum (ER) stress,followed by induction of cytotoxicity in vitro or lethal severe hemorrhagic inflammation in mice. Here we found that steroids and diacylglycerol (DAG) analogues (e.g.,bryostatin 1,Ingenol-3-angelate) inhibited SubAB cytotoxicity. In addition,steroid-induced Bcl-xL expression was a key step in the inhibition of SubAB cytotoxicity. Bcl-xL knockdown increased SubAB-induced apoptosis in steroid-treated HeLa cells,whereas SubAB-induced cytotoxicity was suppressed in Bcl-xL overexpressing cells. In contrast,DAG analogues suppressed SubAB activity independent of Bcl-xL expression at early time points. Addition of Shiga toxin 2 (Stx2) with SubAB to cells enhanced cytotoxicity even in the presence of steroids. In contrast,DAG analogues suppressed cytotoxicity seen in the presence of both toxins. Here,we show the mechanism by which steroids and DAG analogues protect cells against SubAB toxin produced by LEE-negative STEC. View Publication

Despite implementation of virtual crossmatches,flow cytometry crossmatches (FCXM) are still used by many transplant centers to determine immunological risk before kidney transplantation. To determine if common profiles of patients prone to false positive FCXM exist,we examined the demographics and native diseases of kidney patients tested with autologous FCXM (n = 480). Improvements to FCXM and cell isolation methods significantly reduced the positive rate from 15.1{\%} to 5.3{\%}. Patients with native diseases considered 'immunological' (vasculitis,lupus,IgA nephropathy) had more positive autologous FCXM (OR = 3.36,p = 0.003) vs. patients with all other diseases. Patients who were tested using our updated method (n = 321) still showed that these immunological diseases were a significant predictor for positive autologous FCXM (OR = 4.79,p = 0.006). Interestingly,patients on peritoneal dialysis (PD) also had significantly more positive autologous FCXM than patients on hemodialysis or waiting for pre-emptive kidney transplants (OR = 3.27,p = 0.02). These findings were confirmed in patients who had false positive allogeneic FCXM. Twenty of 24 (83.3{\%}) patients with false positive allogeneic FCXM tested with updated method either had immunological diseases originally or were on PD. Our findings are helpful when interpreting an unexpected positive FCXM,especially for transplantation from deceased donors. View Publication

The vascular wall is a source of progenitor cells that are able to induce skeletal repair,primarily by paracrine mechanisms. Here,the paracrine role of extracellular vesicles (EVs) in bone healing was investigated. First,purified human perivascular stem cells (PSCs) were observed to induce mitogenic,pro-migratory,and pro-osteogenic effects on osteoprogenitor cells while in non-contact co-culture via elaboration of EVs. PSC-derived EVs shared mitogenic,pro-migratory,and pro-osteogenic properties of their parent cell. PSC-EV effects were dependent on surface-associated tetraspanins,as demonstrated by EV trypsinization,or neutralizing antibodies for CD9 or CD81. Moreover,shRNA knockdown in recipient cells demonstrated requirement for the CD9/CD81 binding partners IGSF8 and PTGFRN for EV bioactivity. Finally,PSC-EVs stimulated bone repair,and did so via stimulation of skeletal cell proliferation,migration,and osteodifferentiation. In sum,PSC-EVs mediate the same tissue repair effects of perivascular stem cells,and represent an 'off-the-shelf' alternative for bone tissue regeneration. View Publication

Ethanol (EtOH)-induced alterations in intestinal homeostasis lead to multi-system pathologies,including liver injury. $\omega$-6 PUFAs exert pro-inflammatory activity,while $\omega$-3 PUFAs promote anti-inflammatory activity that is mediated,in part,through specialized pro-resolving mediators [e.g.,resolvin D1 (RvD1)]. We tested the hypothesis that a decrease in the $\omega$-6:$\omega$-3 PUFA ratio would attenuate EtOH-mediated alterations in the gut-liver axis. $\omega$-3 FA desaturase-1 (fat-1) mice,which endogenously increase $\omega$-3 PUFA levels,were protected against EtOH-mediated downregulation of intestinal tight junction proteins in organoid cultures and in vivo. EtOH- and lipopolysaccharide-induced expression of INF-$\gamma$,Il-6,and Cxcl1 was attenuated in fat-1 and WT RvD1-treated mice. RNA-seq of ileum tissue revealed upregulation of several genes involved in cell proliferation,stem cell renewal,and antimicrobial defense (including Alpi and Leap2) in fat-1 versus WT mice fed EtOH. fat-1 mice were also resistant to EtOH-mediated downregulation of genes important for xenobiotic/bile acid detoxification. Further,gut microbiome and plasma metabolomics revealed several changes in fat-1 versus WT mice that may contribute to a reduced inflammatory response. Finally,these data correlated with a significant reduction in liver injury. Our study suggests that $\omega$-3 PUFA enrichment or treatment with resolvins can attenuate the disruption in intestinal homeostasis caused by EtOH consumption and systemic inflammation with a concomitant reduction in liver injury. View Publication