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1.
Nat Immunol ; 23(10): 1433-1444, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36138184

RESUMO

Naive T cells undergo radical changes during the transition from dormant to hyperactive states upon activation, which necessitates de novo protein production via transcription and translation. However, the mechanism whereby T cells globally promote translation remains largely unknown. Here, we show that on exit from quiescence, T cells upregulate transfer RNA (tRNA) m1A58 'writer' proteins TRMT61A and TRMT6, which confer m1A58 RNA modification on a specific subset of early expressed tRNAs. These m1A-modified early tRNAs enhance translation efficiency, enabling rapid and necessary synthesis of MYC and of a specific group of key functional proteins. The MYC protein then guides the exit of naive T cells from a quiescent state into a proliferative state and promotes rapid T cell expansion after activation. Conditional deletion of the Trmt61a gene in mouse CD4+ T cells causes MYC protein deficiency and cell cycle arrest, disrupts T cell expansion upon cognate antigen stimulation and alleviates colitis in a mouse adoptive transfer colitis model. Our study elucidates for the first time, to our knowledge, the in vivo physiological roles of tRNA-m1A58 modification in T cell-mediated pathogenesis and reveals a new mechanism of tRNA-m1A58-controlled T cell homeostasis and signal-dependent translational control of specific key proteins.


Assuntos
Colite , RNA de Transferência , Transferência Adotiva , Animais , Proliferação de Células/genética , Colite/genética , Camundongos , Biossíntese de Proteínas , RNA de Transferência/genética , RNA de Transferência/metabolismo , Linfócitos T/metabolismo
2.
Mol Cell ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39002544

RESUMO

5-methylcytosine (m5C) is a prevalent RNA modification crucial for gene expression regulation. However, accurate and sensitive m5C sites identification remains challenging due to severe RNA degradation and reduced sequence complexity during bisulfite sequencing (BS-seq). Here, we report m5C-TAC-seq, a bisulfite-free approach combining TET-assisted m5C-to-f5C oxidation with selective chemical labeling, therefore enabling direct base-resolution m5C detection through pre-enrichment and C-to-T transitions at m5C sites. With m5C-TAC-seq, we comprehensively profiled the m5C methylomes in human and mouse cells, identifying a substantially larger number of confident m5C sites. Through perturbing potential m5C methyltransferases, we deciphered the responsible enzymes for most m5C sites, including the characterization of NSUN5's involvement in mRNA m5C deposition. Additionally, we characterized m5C dynamics during mESC differentiation. Notably, the mild reaction conditions and preservation of nucleotide composition in m5C-TAC-seq allow m5C detection in chromatin-associated RNAs. The accurate and robust m5C-TAC-seq will advance research into m5C methylation functional investigation.

3.
Nature ; 608(7924): 766-777, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948637

RESUMO

Myocardial infarction is a leading cause of death worldwide1. Although advances have been made in acute treatment, an incomplete understanding of remodelling processes has limited the effectiveness of therapies to reduce late-stage mortality2. Here we generate an integrative high-resolution map of human cardiac remodelling after myocardial infarction using single-cell gene expression, chromatin accessibility and spatial transcriptomic profiling of multiple physiological zones at distinct time points in myocardium from patients with myocardial infarction and controls. Multi-modal data integration enabled us to evaluate cardiac cell-type compositions at increased resolution, yielding insights into changes of the cardiac transcriptome and epigenome through the identification of distinct tissue structures of injury, repair and remodelling. We identified and validated disease-specific cardiac cell states of major cell types and analysed them in their spatial context, evaluating their dependency on other cell types. Our data elucidate the molecular principles of human myocardial tissue organization, recapitulating a gradual cardiomyocyte and myeloid continuum following ischaemic injury. In sum, our study provides an integrative molecular map of human myocardial infarction, represents an essential reference for the field and paves the way for advanced mechanistic and therapeutic studies of cardiac disease.


Assuntos
Remodelamento Atrial , Montagem e Desmontagem da Cromatina , Perfilação da Expressão Gênica , Infarto do Miocárdio , Análise de Célula Única , Remodelação Ventricular , Remodelamento Atrial/genética , Estudos de Casos e Controles , Cromatina/genética , Epigenoma , Humanos , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fatores de Tempo , Remodelação Ventricular/genética
4.
Mol Cell ; 77(2): 426-440.e6, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31676230

RESUMO

N6-methyladenosine (m6A), the most abundant internal mRNA modification, and N6,2'-O-dimethyladenosine (m6Am), found at the first-transcribed nucleotide, are two reversible epitranscriptomic marks. However, the profiles and distribution patterns of m6A and m6Am across human and mouse tissues are poorly characterized. Here, we report the m6A and m6Am methylome through profiling of 43 human and 16 mouse tissues and demonstrate strongest tissue specificity for the brain tissues. A small subset of tissue-specific m6A peaks can also readily classify tissue types. The overall m6A and m6Am level is partially correlated with the expression level of their writers and erasers. Additionally, the m6A-containing regions are enriched for SNPs. Furthermore, cross-species analysis revealed that species rather than tissue type is the primary determinant of methylation. Collectively, our study provides an in-depth resource for dissecting the landscape and regulation of the m6A and m6Am epitranscriptomic marks across mammalian tissues.


Assuntos
RNA Mensageiro/genética , Animais , Encéfalo/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Células HT29 , Células HeLa , Humanos , Células Jurkat , Células K562 , Masculino , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Polimorfismo de Nucleotídeo Único/genética
5.
Nature ; 589(7841): 281-286, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33176333

RESUMO

Kidney fibrosis is the hallmark of chronic kidney disease progression; however, at present no antifibrotic therapies exist1-3. The origin, functional heterogeneity and regulation of scar-forming cells that occur during human kidney fibrosis remain poorly understood1,2,4. Here, using single-cell RNA sequencing, we profiled the transcriptomes of cells from the proximal and non-proximal tubules of healthy and fibrotic human kidneys to map the entire human kidney. This analysis enabled us to map all matrix-producing cells at high resolution, and to identify distinct subpopulations of pericytes and fibroblasts as the main cellular sources of scar-forming myofibroblasts during human kidney fibrosis. We used genetic fate-tracing, time-course single-cell RNA sequencing and ATAC-seq (assay for transposase-accessible chromatin using sequencing) experiments in mice, and spatial transcriptomics in human kidney fibrosis, to shed light on the cellular origins and differentiation of human kidney myofibroblasts and their precursors at high resolution. Finally, we used this strategy to detect potential therapeutic targets, and identified NKD2 as a myofibroblast-specific target in human kidney fibrosis.


Assuntos
Linhagem da Célula , Fibrose/patologia , Túbulos Renais/patologia , Miofibroblastos/patologia , Insuficiência Renal Crônica/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Estudos de Casos e Controles , Diferenciação Celular , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Masculino , Mesoderma/citologia , Mesoderma/patologia , Camundongos , Miofibroblastos/metabolismo , Pericitos/citologia , Pericitos/patologia , RNA-Seq , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Análise de Célula Única , Transcriptoma
6.
RNA ; 30(5): 537-547, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38531648

RESUMO

Over the past decade, advancements in epitranscriptomics have significantly enhanced our understanding of mRNA metabolism and its role in human development and diseases. This period has witnessed breakthroughs in sequencing technologies and the identification of key proteins involved in RNA modification processes. Alongside the well-studied m6A, Ψ and m1A have emerged as key epitranscriptomic markers. Initially identified through transcriptome-wide profiling, these modifications are now recognized for their broad impact on RNA metabolism and gene expression. In this Perspective, we focus on the detections and functions of Ψ and m1A modifications in mRNA and discuss previous discrepancies and future challenges. We summarize recent advances and highlight the latest sequencing technologies for stoichiometric detection and their mechanistic investigations for functional unveiling in mRNA as the new research directions.


Assuntos
Processamento Pós-Transcricional do RNA , Transcriptoma , Humanos , RNA Mensageiro/genética , Sequenciamento de Nucleotídeos em Larga Escala , Perfilação da Expressão Gênica , RNA
7.
Environ Res ; 245: 118078, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38159665

RESUMO

Highly efficient resource recycling and comprehensive utilization play a crucial role in achieving the goal of reducing resource wasting, environmental protection, and achieving goal of sustainable development. In this work, the two kinds waste resources of agricultural rice husk and metal ions (Co, Ni, and Mn) from spent lithium-ion batteries have been skillfully utilized to synthesize novel Fenton-like catalysts. Desiliconized rice husk carbon (DRHC) with rich pore structure and large specific surface area from rice husk has been prepared and used as scalable carrier, and dandelion-like nanoparticles cluster could be grown in situ on the surface of the carrier by using metal ions contained waste water. The designed catalysts (X@DRHC) as well as their preparation process were characterized in detail by SEM, TEM, BET, XRD and XPS, respectively. Meanwhile, their catalytic abilities were also studied by activating potassium peroxomonosulfate (PMS) to remove methylene blue (MB). The results indicate X@DRHC displays excellent degradation efficiency on MB with wide pH range and stable reusability, which is suitable for the degradation of various dyes. This work has realized the recycling and high-value utilization of waste resources from biomass and spent lithium-ion batteries, which not only creates an efficient way to dispose waste resources, but also shows high economic benefits in large-scale water treatment.


Assuntos
Lítio , Oryza , Peróxidos , Carbono , Metais , Reciclagem/métodos , Fontes de Energia Elétrica , Íons
8.
J Nanobiotechnology ; 22(1): 338, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890737

RESUMO

BACKGROUND: Incomplete radiofrequency ablation (iRFA) in hepatocellular carcinoma (HCC) often leads to local recurrence and distant metastasis of the residual tumor. This is closely linked to the development of a tumor immunosuppressive environment (TIME). In this study, underlying mechanisms and potential therapeutic targets involved in the formation of TIME in residual tumors following iRFA were explored. Then, TAK-981-loaded nanocomposite hydrogel was constructed, and its therapeutic effects on residual tumors were investigated. RESULTS: This study reveals that the upregulation of small ubiquitin-like modifier 2 (Sumo2) and activated SUMOylation is intricately tied to immunosuppression in residual tumors post-iRFA. Both knockdown of Sumo2 and inhibiting SUMOylation with TAK-981 activate IFN-1 signaling in HCC cells, thereby promoting dendritic cell maturation. Herein, we propose an injectable PDLLA-PEG-PDLLA (PLEL) nanocomposite hydrogel which incorporates self-assembled TAK-981 and BSA nanoparticles for complementary localized treatment of residual tumor after iRFA. The sustained release of TAK-981 from this hydrogel curbs the expansion of residual tumors and notably stimulates the dendritic cell and cytotoxic lymphocyte-mediated antitumor immune response in residual tumors while maintaining biosafety. Furthermore, the treatment with TAK-981 nanocomposite hydrogel resulted in a widespread elevation in PD-L1 levels. Combining TAK-981 nanocomposite hydrogel with PD-L1 blockade therapy synergistically eradicates residual tumors and suppresses distant tumors. CONCLUSIONS: These findings underscore the potential of the TAK-981-based strategy as an effective therapy to enhance RFA therapy for HCC.


Assuntos
Carcinoma Hepatocelular , Hidrogéis , Neoplasias Hepáticas , Nanocompostos , Ablação por Radiofrequência , Sumoilação , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Animais , Hidrogéis/química , Nanocompostos/química , Nanocompostos/uso terapêutico , Humanos , Camundongos , Ablação por Radiofrequência/métodos , Sumoilação/efeitos dos fármacos , Linhagem Celular Tumoral , Masculino
9.
Cell Mol Biol Lett ; 29(1): 28, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395751

RESUMO

BACKGROUND: Bladder cancer (BCa) ranks among the predominant malignancies affecting the urinary system. Cisplatin (CDDP) remains a cornerstone therapeutic agent for BCa management. Recent insights suggest pivotal roles of circular RNA (circRNA) and N6-methyladenosine (m6A) in modulating CDDP resistance in BCa, emphasizing the importance of elucidating these pathways to optimize cisplatin-based treatments. METHODS: Comprehensive bioinformatics assessments were undertaken to discern circ_104797 expression patterns, its specific interaction domains, and m6A motifs. These findings were subsequently corroborated through experimental validations. To ascertain the functional implications of circ_104797 in BCa metastasis, in vivo assays employing CRISPR/dCas13b-ALKBH5 were conducted. Techniques, such as RNA immunoprecipitation, biotin pull-down, RNA pull-down, luciferase reporter assays, and western blotting, were employed to delineate the underlying molecular intricacies. RESULTS: Our investigations revealed an elevated expression of circ_104797 in CDDP-resistant BCa cells, underscoring its pivotal role in sustaining cisplatin resistance. Remarkably, demethylation of circ_104797 markedly augmented the potency of cisplatin-mediated apoptosis. The amplification of circ_104797 in CDDP-resistant cells was attributed to enhanced RNA stability, stemming from an augmented m6A level at a distinct adenosine within circ_104797. Delving deeper, we discerned that circ_104797 functioned as a microRNA reservoir, specifically sequestering miR-103a and miR-660-3p, thereby potentiating cisplatin resistance. CONCLUSIONS: Our findings unveil a previously uncharted mechanism underpinning cisplatin resistance and advocate the potential therapeutic targeting of circ_104797 in cisplatin-administered patients with BCa, offering a promising avenue for advanced BCa management.


Assuntos
Adenosina/análogos & derivados , MicroRNAs , Neoplasias da Bexiga Urinária , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-38430174

RESUMO

Objective: To explore the effect of evidence-based care plus aerobic exercise on blood pressure control and pregnancy outcome in patients with hypertensive disorders during pregnancy. Methods: A total of 100 patients diagnosed with hypertensive disorder in pregnancy treated in our hospital between February 2020 and November 2021 were recruited, analyzed and assigned at a ratio of 1:1 to receive routine nursing (control group) or evidence-based care plus aerobic exercise (experimental group) via random number table method. Outcome measures included blood pressure, negative emotions, sleep duration, and pregnancy outcome. Results: The blood pressure of both groups decreased after nursing, and the diastolic and systolic blood pressure of patients in the experimental group (79.84±5.18 mmHg, 111.62±7.96 mmHg) were lower than those in the control group (88.65±5.69 mmHg, 132.15±8.14 mmHg) (P < .05). After the completion of the nursing period, assessments using the Self-Rating Anxiety Scale and Hamilton Depression Scale were conducted. The results revealed significantly lower scores in the experimental group, which received evidence-based care along with aerobic exercise, compared to the control patients who received routine care. The sleep duration was prolonged in both groups after nursing, and patients in the experimental group got longer sleep duration than those in the control group (P < .05). The experimental group showed a significantly lower incidence of adverse pregnancy outcomes than the control group (P < .05). Limitations: While our study demonstrates the positive impact of evidence-based care combined with moderate aerobic exercise on patients with hypertensive disorders during pregnancy, it is essential to acknowledge some notable limitations. First, the sample size was relatively small, which may limit the generalizability of our findings to a larger population. Furthermore, our study primarily focused on short-term outcomes, and future research could explore the sustained benefits of this approach. Finally, individual variations in exercise tolerance and compliance may also affect the effectiveness of the intervention. Despite these limitations, our findings hold promise and provide a foundation for further research in this area. Conclusion: Evidence-based care combined with moderate aerobic exercise has proven to be an effective approach in enhancing the overall management of patients with hypertensive disorders during pregnancy. This combined intervention not only effectively regulates blood pressure levels but also mitigates adverse emotional states, enhances sleep quality, and ultimately leads to improved pregnancy outcomes. These findings hold significant promise for clinical application. Healthcare providers may consider implementing this approach to improve the well-being of pregnant individuals with hypertensive disorders, potentially reducing the risk of complications and enhancing the overall quality of care. Pregnant individuals, on the other hand, can benefit from a more comprehensive and holistic approach to their care, which may result in better health and pregnancy outcomes. Future research in this area could explore the long-term sustainability and cost-effectiveness of this intervention, as well as its potential applicability to diverse patient populations and healthcare settings.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38290439

RESUMO

Objective: This study aimed to evaluate the impact of quality care on maternal and infant outcomes in patients with hypertensive disorders complicating pregnancy (HDCP) complicated by cerebral hemorrhage. Methods: From February 2020 to September 2021, 68 women with HDCP complicated by cerebral hemorrhage hospitalized at our hospital were included and divided into a routine group (standard care) and a quality group (quality care). Outcome measures included National Institutes of Health Stroke Scale (NIHSS) scores, blood pressure, self-rating anxiety scale (SAS) scores, self-rating depression scale (SDS) scores, and maternal and infant outcomes. Results: Patients in the quality group (3.22±1.89) had significantly lower NIHSS scores aftercare than those in the routine group (6.15±3.24) (P < .05). Quality care resulted in lower diastolic blood pressure (Quality group:81.23±6.15; Routine: 90.58±7.98), systolic blood pressure (Quality group:125.49±13.37; Routine: 139.74±16.67), SAS scores (Quality group: 48.42±2.65; Routine: 58.15±2.43), and SDS scores versus routine care (Quality group:48.42±2.65; Routine: 58.15±2.43)(P < .05). The quality group showed a lower incidence of adverse maternal and infant pregnancy outcomes than the routine group (P < .05). Conclusion: The findings underscore the positive impact of quality care in reducing adverse maternal and newborn pregnancy outcomes. This reduction is particularly significant for clinical practice, as it is achieved through the amelioration of various factors, such as neurological impairments, blood pressure regulation, and the alleviation of negative emotions, including anxiety and depression, in patients with HDCP complicated by cerebral hemorrhage. The practical implications of these findings for healthcare providers and patients are substantial. They highlight the potential to improve patient outcomes, enhance the overall quality of care, and reduce the burden on healthcare systems. By addressing these factors, healthcare providers can enhance the well-being of both mothers and newborns, leading to improved clinical outcomes and increased patient satisfaction.

12.
Inflammopharmacology ; 32(1): 537-550, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37620622

RESUMO

Sepsis is a complex, multifactorial syndrome characterized by a dysregulated host response to infection, leading to severe organ dysfunction and high mortality rates among critically ill patients. Hypovitaminosis C and vitamin C deficiency are frequently observed in septic patients, prompting interest in the potential therapeutic role of ascorbic acid. Although intravenous administration of ascorbic acid has been investigated in multiple clinical trials for sepsis treatment, the specific immunomodulatory mechanisms underlying its effects remain elusive. This study aimed to investigate the protective effects of high-dose ascorbic acid on experimental sepsis. Results show that intravenous administration of high-dose ascorbic acid (250 mg/kg) attenuated sepsis-induced organ dysfunctions in a cecal ligation and puncture (CLP)-induced septic mouse model. Ascorbic acid improved splenic cell apoptosis and increased the number of CD3+ T cells in septic mice induced by CLP. Furthermore, ascorbic acid downregulated PD-L1 expression in livers, reduced PD-1 expression in spleens, and inhibited the phosphorylation of STAT1 at Y701 in multiple organs of CLP-induced septic mice. The in vitro experiments also revealed that 800 µM ascorbic acid suppressed STAT1 phosphorylation and inhibited lipopolysaccharide (LPS) and IFN-γ-induced PD-L1 expression in macrophages. These findings suggest that ascorbic acid prevents sepsis-associated organ dysfunction through the p-STAT1/PD-L1 signaling pathway. Our study provides new insights into the potential therapeutic use of ascorbic acid in sepsis.


Assuntos
Antineoplásicos , Sepse , Humanos , Animais , Camundongos , Antígeno B7-H1 , Insuficiência de Múltiplos Órgãos , Fosforilação , Sepse/tratamento farmacológico , Ácido Ascórbico/farmacologia , Fator de Transcrição STAT1
13.
Angew Chem Int Ed Engl ; 63(1): e202315861, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37985247

RESUMO

Atherosclerosis is a lipoprotein-driven disease, and there is no effective therapy to reverse atherosclerosis or existing plaques. Therefore, it is urgently necessary to create a noninvasive and reliable approach for early atherosclerosis detection to prevent initial plaque formation. Atherosclerosis is intimately associated with inflammation, which is accompanied by an excess of reactive oxygen species (ROS), leading to cells requiring more glutathione (GSH) to resist severe oxidative stress. Therefore, the GSH-hydrolyzed protein γ-glutamyl transpeptidase (GGT) and the ROS-hypobromous acid (HBrO) are potential biomarkers for predicting atherogenesis. Hence, to avoid false-positive diagnoses caused by a single biomarker, we constructed an ingenious sequence-activated double-locked TP fluorescent probe, C-HBrO-GGT, in which two sequential triggers of GGT and HBrO are meticulously designed to ensure that the probe fluoresces in response to HBrO only after GGT hydrolyzes the probe. By utilization of C-HBrO-GGT, the voltage-gated chloride channel (CLC-1)-HBrO-catalase (CAT)-GGT signaling pathway was confirmed in cellular level. Notably, the forthcoming atherosclerotic plaques were successfully predicted before the plaques could be observed via the naked eye or classical immunofluorescent staining. Collectively, this research proposed a powerful tool to indicate the precise position of mature plaques and provide early warning of atherosclerotic plaques.


Assuntos
Aterosclerose , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/diagnóstico por imagem , gama-Glutamiltransferase/metabolismo , Corantes Fluorescentes/metabolismo , Fluorescência , Espécies Reativas de Oxigênio , Aterosclerose/diagnóstico
14.
BMC Genomics ; 24(1): 209, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37076818

RESUMO

BACKGROUND: Sulfate-reducing bacteria (SRB) drive the ocean sulfur and carbon cycling. They constitute a diverse phylogenetic and physiological group and are widely distributed in anoxic marine environments. From a physiological viewpoint, SRB's can be categorized as complete or incomplete oxidizers, meaning that they either oxidize their carbon substrate completely to CO2 or to a stoichiometric mix of CO2 and acetate. Members of Desulfofabaceae family are incomplete oxidizers, and within that family, Desulfofaba is the only genus with three isolates that are classified into three species. Previous physiological experiments revealed their capability of respiring oxygen. RESULTS: Here, we sequenced the genomes of three isolates in Desulfofaba genus and reported on a genomic comparison of the three species to reveal their metabolic potentials. Based on their genomic contents, they all could oxidize propionate to acetate and CO2. We confirmed their phylogenetic position as incomplete oxidizers based on dissimilatory sulfate reductase (DsrAB) phylogeny. We found the complete pathway for dissimilatory sulfate reduction, but also different key genes for nitrogen cycling, including nitrogen fixation, assimilatory nitrate/nitrite reduction, and hydroxylamine reduction to nitrous oxide. Their genomes also contain genes that allow them to cope with oxygen and oxidative stress. They have genes that encode for diverse central metabolisms for utilizing different substrates with the potential for more strains to be isolated in the future, yet their distribution is limited. CONCLUSIONS: Results based on marker gene search and curated metagenome assembled genomes search suggest a limited environmental distribution of this genus. Our results reveal a large metabolic versatility within the Desulfofaba genus which establishes their importance in biogeochemical cycling of carbon in their respective habitats, as well as in the support of the entire microbial community through releasing easily degraded organic matters.


Assuntos
Dióxido de Carbono , Sulfatos , Sulfatos/metabolismo , Filogenia , Dióxido de Carbono/metabolismo , Bactérias/genética , Genômica , Oxirredução , Carbono/metabolismo
15.
Gastroenterology ; 163(4): 891-907, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35700773

RESUMO

BACKGROUND & AIMS: N6-Methyladenosine (m6A) is the most prevalent RNA modification and recognized as an important epitranscriptomic mechanism in colorectal cancer (CRC). We aimed to exploit whether and how tumor-intrinsic m6A modification driven by methyltransferase like 3 (METTL3) can dictate the immune landscape of CRC. METHODS: Mettl3 knockout mice, CD34+ humanized mice, and different syngeneic mice models were used. Immune cell composition and cytokine level were analyzed by flow cytometry and Cytokine 23-Plex immunoassay, respectively. M6A sequencing and RNA sequencing were performed to identify downstream targets and pathways of METTL3. Human CRC specimens (n = 176) were used to evaluate correlation between METTL3 expression and myeloid-derived suppressor cell (MDSC) infiltration. RESULTS: We demonstrated that silencing of METTL3 in CRC cells reduced MDSC accumulation to sustain activation and proliferation of CD4+ and CD8+ T cells, and eventually suppressed CRC in ApcMin/+Mettl3+/- mice, CD34+ humanized mice, and syngeneic mice models. Mechanistically, METTL3 activated the m6A-BHLHE41-CXCL1 axis by analysis of m6A sequencing, RNA sequencing, and cytokine arrays. METTL3 promoted BHLHE41 expression in an m6A-dependent manner, which subsequently induced CXCL1 transcription to enhance MDSC migration in vitro. However, the effect was negligible on BHLHE41 depletion, CXCL1 protein or CXCR2 inhibitor SB265610 administration, inferring that METTL3 promotes MDSC migration via BHLHE41-CXCL1/CXCR2. Consistently, depletion of MDSCs by anti-Gr1 antibody or SB265610 blocked the tumor-promoting effect of METTL3 in vivo. Importantly, targeting METTL3 by METTL3-single guide RNA or specific inhibitor potentiated the effect of anti-programmed cell death protein 1 (anti-PD1) treatment. CONCLUSIONS: Our study identifies METTL3 as a potential therapeutic target for CRC immunotherapy whose inhibition reverses immune suppression through the m6A-BHLHE41-CXCL1 axis. METTL3 inhibition plus anti-PD1 treatment shows promising antitumor efficacy against CRC.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias Colorretais , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Quimiocina CXCL1 , Neoplasias Colorretais/patologia , Citocinas/metabolismo , Humanos , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Camundongos Knockout , Compostos de Fenilureia , RNA Guia de Cinetoplastídeos , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/metabolismo , Triazóis
16.
J Transl Med ; 21(1): 218, 2023 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-36964576

RESUMO

BACKGROUND: The recurrence of hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) remains a major clinical problem. Cells that survive the sublethal heat stress that is induced by incomplete RFA are the main source of HCC relapse. Heat stress has long been reported to increase intracellular reactive oxygen species (ROS) generation. Although ROS can induce apoptosis, a pro-survival effect of ROS has also been demonstrated. However, the role of ROS in HCC cells exposed to sublethal heat stress remains unclear. METHODS: HepG2 and HuH7 cells were used for this experiment. Insufficient RFA was performed in cells and in a xenograft model. ROS and antioxidant levels were measured. Apoptosis was analyed by Annexin-V/PI staining and flow cytometry. Protein expression was measured using western blotting. Colocalization of lysosomes and mitochondria was analyzed to assess mitophagy. Corresponding activators or inhibitors were applied to verify the function of specific objectives. RESULTS: Here,we showed that sublethal heat stress induced a ROS burst, which caused acute oxidative stress. This ROS burst was generated by mitochondria, and it was initiated by upregulated NOX4 expression in the mitochondria. N-acetylcysteine (NAC) decreased HCC cell survival under sublethal heat stress conditions in vivo and in vitro. NOX4 triggers the production of mitochondrial ROS (mtROS), and NOX4 inhibitors or siNOX4 also decreased HCC cell survival under sublethal heat stress conditions in vitro. Increased mtROS trigger PINK1-dependent mitophagy to eliminate the mitochondria that are damaged by sublethal heat stress and to protect cells from apoptosis. Nrf2 expression was elevated in response to this ROS burst and mediated the ROS burst-induced increase in PINK1 expression after sublethal heat stress. CONCLUSION: These data confirmed that the ROS burst that occurs after iRFA exerted a pro-survival effect. NOX4 increased the generation of ROS by mitochondria. This short-term ROS burst induced PINK1-dependent mitophagy to eliminate damaged mitochondria by increasing Nrf2 expression.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ablação por Radiofrequência , Humanos , Mitofagia , Carcinoma Hepatocelular/patologia , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Regulação para Cima , Sobrevivência Celular , Proteínas Quinases/metabolismo , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Mitocôndrias/metabolismo , NADPH Oxidase 4/metabolismo
17.
Haematologica ; 108(10): 2677-2689, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37165848

RESUMO

Aged hematopoietic stem cells (HSC) exhibit compromised reconstitution capacity and differentiation-bias towards myeloid lineage, however, the molecular mechanism behind it remains not fully understood. In this study, we observed that the expression of pseudouridine (Ψ) synthase 10 is increased in aged hematopoietic stem and progenitor cells (HSPC) and enforced protein of Ψ synthase 10 (PUS10) recapitulates the phenotype of aged HSC, which is not achieved by its Ψ synthase activity. Consistently, we observed no difference of transcribed RNA pseudouridylation profile between young and aged HSPC. No significant alteration of hematopoietic homeostasis and HSC function is observed in young Pus10-/- mice, while aged Pus10-/- mice exhibit mild alteration of hematopoietic homeostasis and HSC function. Moreover, we observed that PUS10 is ubiquitinated by E3 ubiquitin ligase CRL4DCAF1 complex and the increase of PUS10 in aged HSPC is due to aging-declined CRL4DCAF1- mediated ubiquitination degradation signaling. Taken together, this study for the first time evaluated the role of PUS10 in HSC aging and function, and provided a novel insight into HSC rejuvenation and its clinical application.


Assuntos
Transferases Intramoleculares , RNA , Animais , Camundongos , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Envelhecimento
18.
Soft Matter ; 20(1): 255-265, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38086671

RESUMO

It is of great research significance to prepare a new shear thickening fluid (STF) with a simple process, remarkable thickening effect and excellent impact resistance from the properties of the particles. Inspired by the shear thickening mechanism, nano-silica particle clusters (SPC) with different morphological structures were prepared by the reaction of amino-modified silica with polyethylene glycol diglycidyl ether (PEGDGE), and the structure models of particle clusters were designed through theoretical analysis. The structure of SPC was affected by the degree of amination modification and the molecular weight of PEGDGE, which was analyzed by DLS and TEM. The shear thickening behavior of the fluid was evaluated by steady-state rheology and dynamic-state rheology analysis. The shear thickening behavior of the fluid composed of SPC also changed greatly with the influence of the degree of amination modification and the molecular weight of PEGDGE. In addition, compared with the STF contained original silica, the STF contained SPC could produce a faster and stronger shear thickening response. Therefore, silica particle clusters are not only a promising candidate for the preparation of high-performance shear thickening fluids, but can also be better applied to industrial and scientific fields such as impact protection and shock absorption.

19.
J Immunol ; 206(5): 1088-1101, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33495235

RESUMO

The skin of vertebrates is the outermost organ of the body and serves as the first line of defense against external aggressions. In contrast to mammalian skin, that of teleost fish lacks keratinization and has evolved to operate as a mucosal surface containing a skin-associated lymphoid tissue (SALT). Thus far, IgT representing the prevalent Ig in SALT have only been reported upon infection with a parasite. However, very little is known about the types of B cells and Igs responding to bacterial infection in the teleost skin mucosa, as well as the inductive or effector role of the SALT in such responses. To address these questions, in this study, we analyzed the immune response of trout skin upon infection with one of the most widespread fish skin bacterial pathogens, Flavobacterium columnare This pathogen induced strong skin innate immune and inflammatory responses at the initial phases of infection. More critically, we found that the skin mucus of fish having survived the infection contained significant IgT- but not IgM- or IgD-specific titers against the bacteria. Moreover, we demonstrate the local proliferation and production of IgT+ B cells and specific IgT titers, respectively, within the SALT upon bacterial infection. Thus, our findings represent the first demonstration that IgT is the main Ig isotype induced by the skin mucosa upon bacterial infection and that, because of the large surface of the skin, its SALT probably represents a prominent IgT-inductive site in fish.


Assuntos
Linfócitos B/imunologia , Infecções por Flavobacteriaceae/imunologia , Imunidade nas Mucosas/imunologia , Imunoglobulinas/imunologia , Mucosa/imunologia , Oncorhynchus mykiss/imunologia , Pele/imunologia , Animais , Proliferação de Células/fisiologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes , Infecções por Flavobacteriaceae/microbiologia , Flavobacterium/imunologia , Imunidade Inata/imunologia , Isotipos de Imunoglobulinas/imunologia , Inflamação/imunologia , Inflamação/microbiologia , Tecido Linfoide/imunologia , Mucosa/microbiologia , Oncorhynchus mykiss/microbiologia , Pele/microbiologia
20.
Lipids Health Dis ; 22(1): 117, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37537579

RESUMO

BACKGROUND: This study analyzed the clinical features and biomarkers of alcohol-associated liver disease (ALD) to investigate the diagnostic value of age, bilirubin, international normalized ratio (INR), and creatinine (ABIC) score to triglyceride (TG) ratio (ABIC/TG) in ALD-associated primary liver carcinoma (PLC). MATERIALS AND METHODS: Data were collected from 410 participants with ALD, and the epidemiological and clinical records of 266 participants were analyzed. Participants were divided into ALD-without-PLC and ALD-associated-PLC groups. Relationships between clinical characteristics, biomarkers and ALD-associated PLC were estimated. Serum lipid levels and liver function were compared between ALD patients without PLC and patients with ALD-associated PLC. Scoring systems were calculated to investigate ALD severity. The robustness of the relationship was analyzed by the receiver operating characteristic (ROC) curve. RESULTS: Age and dyslipidemia were more strongly associated with ALD-associated PLC than with ALD-without PLC, with AORs of 2.39 and 0.25, respectively, with P less than 0.05. Drinking time and average daily intake, ABIC score, and ABIC/TG ratio were significantly higher in the ALD-associated-PLC group than in the ALD-without-PLC group. The AUC for the ABIC/TG ratio predicting the incidence of PLC was 0.80 (P < 0.01), which was higher than that of the ABIC and TG scores alone; additionally, the specificity and Youden index for the ABIC/TG ratio were also higher, and the cutoff value was 6.99. CONCLUSIONS: In ALD patients, age, drinking time, and average daily intake were risk factors for PLC. Drinking time, average daily intake, TG and ABIC score have diagnostic value for ALD-associated PLC. The ABIC/TG ratio had a higher AUC value and Youden index than the ABIC score and TG level.


Assuntos
Bilirrubina , Carcinoma , Humanos , Estudos Retrospectivos , Creatinina , Coeficiente Internacional Normatizado , Triglicerídeos , Prognóstico , Índice de Gravidade de Doença , Valor Preditivo dos Testes , Biomarcadores , Etanol , Fígado
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