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1.
Nat Immunol ; 23(4): 568-580, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35314846

RESUMO

Tumor-associated macrophages are composed of distinct populations arising from monocytes or tissue macrophages, with a poorly understood link to disease pathogenesis. Here, we demonstrate that mouse monocyte migration was supported by glutaminyl-peptide cyclotransferase-like (QPCTL), an intracellular enzyme that mediates N-terminal modification of several substrates, including the monocyte chemoattractants CCL2 and CCL7, protecting them from proteolytic inactivation. Knockout of Qpctl disrupted monocyte homeostasis, attenuated tumor growth and reshaped myeloid cell infiltration, with loss of monocyte-derived populations with immunosuppressive and pro-angiogenic profiles. Antibody targeting of the receptor CSF1R, which more broadly eliminates tumor-associated macrophages, reversed tumor growth inhibition in Qpctl-/- mice and prevented lymphocyte infiltration. Modulation of QPCTL synergized with anti-PD-L1 to expand CD8+ T cells and limit tumor growth. QPCTL inhibition constitutes an effective approach for myeloid cell-targeted cancer immunotherapy.


Assuntos
Aminoaciltransferases , Linfócitos T CD8-Positivos , Quimiocinas , Neoplasias , Aminoaciltransferases/genética , Aminoaciltransferases/metabolismo , Animais , Linfócitos T CD8-Positivos/patologia , Quimiocinas/metabolismo , Imunoterapia , Infiltração Leucêmica , Camundongos , Camundongos Knockout , Monócitos , Neoplasias/imunologia
2.
Immunity ; 55(8): 1466-1482.e9, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35863346

RESUMO

Although many studies have addressed the regulatory circuits affecting neuronal activities, local non-synaptic mechanisms that determine neuronal excitability remain unclear. Here, we found that microglia prevented overactivation of pre-sympathetic neurons in the hypothalamic paraventricular nucleus (PVN) at steady state. Microglia constitutively released platelet-derived growth factor (PDGF) B, which signaled via PDGFRα on neuronal cells and promoted their expression of Kv4.3, a key subunit that conducts potassium currents. Ablation of microglia, conditional deletion of microglial PDGFB, or suppression of neuronal PDGFRα expression in the PVN elevated the excitability of pre-sympathetic neurons and sympathetic outflow, resulting in a profound autonomic dysfunction. Disruption of the PDGFBMG-Kv4.3Neuron pathway predisposed mice to develop hypertension, whereas central supplementation of exogenous PDGFB suppressed pressor response when mice were under hypertensive insult. Our results point to a non-immune action of resident microglia in maintaining the balance of sympathetic outflow, which is important in preventing cardiovascular diseases.


Assuntos
Hipertensão , Microglia , Animais , Hipertensão/metabolismo , Camundongos , Neurônios/fisiologia , Potássio/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo
3.
Nucleic Acids Res ; 52(11): 6333-6346, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38634797

RESUMO

Transcription-coupled repair (TCR) and global genomic repair (GGR) are two subpathways of nucleotide excision repair (NER). The TFIIH subunit Tfb1 contains a Pleckstrin homology domain (PHD), which was shown to interact with one PHD-binding segment (PB) of Rad4 and two PHD-binding segments (PB1 and PB2) of Rad2 in vitro. Whether and how the different Rad2 and Rad4 PBs interact with the same Tfb1 PHD, and whether and how they affect TCR and GGR within the cell remain mysterious. We found that Rad4 PB constitutively interacts with Tfb1 PHD, and the two proteins may function within one module for damage recognition in TCR and GGR. Rad2 PB1 protects Tfb1 from degradation and interacts with Tfb1 PHD at a basal level, presumably within transcription preinitiation complexes when NER is inactive. During a late step of NER, the interaction between Rad2 PB1 and Tfb1 PHD augments, enabling efficient TCR and GGR. Rather than interacting with Tfb1 PHD, Rad2 PB2 constrains the basal interaction between Rad2 PB1 and Tfb1 PHD, thereby weakening the protection of Tfb1 from degradation and enabling rapid augmentation of their interactions within TCR and GGR complexes. Our results shed new light on NER mechanisms.


Assuntos
Reparo do DNA , Proteínas de Saccharomyces cerevisiae , Transcrição Gênica , Dano ao DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Endodesoxirribonucleases , Reparo por Excisão , Ligação Proteica , Domínios Proteicos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Fator de Transcrição TFIIH/metabolismo , Fator de Transcrição TFIIH/genética
4.
Nucleic Acids Res ; 52(D1): D1024-D1032, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37941143

RESUMO

The silkworm Bombyx mori is a domesticated insect that serves as an animal model for research and agriculture. The silkworm super-pan-genome dataset, which we published last year, is a unique resource for the study of global genomic diversity and phenotype-genotype association. Here we present SilkMeta (http://silkmeta.org.cn), a comprehensive database covering the available silkworm pan-genome and multi-omics data. The database contains 1082 short-read genomes, 546 long-read assembled genomes, 1168 transcriptomes, 294 phenotype characterizations (phenome), tens of millions of variations (variome), 7253 long non-coding RNAs (lncRNAs), 18 717 full length transcripts and a set of population statistics. We have compiled publications on functional genomics research and genetic stock deciphering (mutant map). A range of bioinformatics tools is also provided for data visualization and retrieval. The large batch of omics data and tools were integrated in twelve functional modules that provide useful strategies and data for comparative and functional genomics research. The interactive bioinformatics platform SilkMeta will benefit not only the silkworm but also the insect biology communities.


Assuntos
Bombyx , Genoma de Inseto , Animais , Bombyx/genética , Biologia Computacional , Genômica , Metadados , Multiômica
5.
Development ; 149(2)2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35088829

RESUMO

A long-standing view in the field of evo-devo is that insect forewings develop without any Hox gene input. The Hox gene Antennapedia (Antp), despite being expressed in the thoracic segments of insects, has no effect on wing development. This view has been obtained from studies in two main model species: Drosophila and Tribolium. Here, we show that partial loss of function of Antp resulted in reduced and malformed adult wings in Bombyx, Drosophila and Tribolium. Antp mediates wing growth in Bombyx by directly regulating the ecdysteriod biosynthesis enzyme gene (shade) in the wing tissue, which leads to local production of the growth hormone 20-hydroxyecdysone. Additional targets of Antp are wing cuticular protein genes CPG24, CPH28 and CPG9, which are essential for wing development. We propose, therefore, that insect wing development occurs in an Antp-dependent manner. This article has an associated 'The people behind the papers' interview.


Assuntos
Proteínas de Homeodomínio/metabolismo , Proteínas de Insetos/metabolismo , Asas de Animais/embriologia , Animais , Bombyx , Drosophila , Ecdisterona/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Insetos/genética , Mutação com Perda de Função , Morfogênese , Tribolium , Asas de Animais/metabolismo
6.
Nat Chem Biol ; 19(12): 1504-1512, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37443393

RESUMO

Continuous evolution can generate biomolecules for synthetic biology and enable evolutionary investigation. The orthogonal DNA replication system (OrthoRep) in yeast can efficiently mutate long DNA fragments in an easy-to-operate manner. However, such a system is lacking in bacteria. Therefore, we developed a bacterial orthogonal DNA replication system (BacORep) for continuous evolution. We achieved this by harnessing the temperate phage GIL16 DNA replication machinery in Bacillus thuringiensis with an engineered error-prone orthogonal DNA polymerase. BacORep introduces all 12 types of nucleotide substitution in 15-kilobase genes on orthogonally replicating linear plasmids with a 6,700-fold higher mutation rate than that of the host genome, the mutation rate of which is unchanged. Here we demonstrate the utility of BacORep-based continuous evolution by generating strong promoters applicable to model bacteria, Bacillus subtilis and Escherichia coli, and achieving a 7.4-fold methanol assimilation increase in B. thuringiensis. BacORep is a powerful tool for continuous evolution in prokaryotic cells.


Assuntos
DNA Polimerase Dirigida por DNA , Saccharomyces cerevisiae , DNA Bacteriano , DNA Polimerase Dirigida por DNA/metabolismo , Plasmídeos/genética , Saccharomyces cerevisiae/genética , Replicação do DNA , Bactérias/genética , Bacillus subtilis/genética , Bacillus subtilis/metabolismo
7.
Mol Biol Evol ; 40(2)2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36718535

RESUMO

The genetic basis of phenotypic variation is a long-standing concern of evolutionary biology. Coloration has proven to be a visual, easily quantifiable, and highly tractable system for genetic analysis and is an ever-evolving focus of biological research. Compared with the homogenized brown-yellow cocoons of wild silkworms, the cocoons of domestic silkworms are spectacularly diverse in color, such as white, green, and yellow-red; this provides an outstanding model for exploring the phenotypic diversification and biological coloration. Herein, the molecular mechanism underlying silkworm green cocoon formation was investigated, which was not fully understood. We demonstrated that five of the seven members of a sugar transporter gene cluster were specifically duplicated in the Bombycidae and evolved new spatial expression patterns predominantly expressed in silk glands, accompanying complementary temporal expression; they synergistically facilitate the uptake of flavonoids, thus determining the green cocoon. Subsequently, polymorphic cocoon coloring landscape involving multiple loci and the evolution of cocoon color from wild to domestic silkworms were analyzed based on the pan-genome sequencing data. It was found that cocoon coloration involved epistatic interaction between loci; all the identified cocoon color-related loci existed in wild silkworms; the genetic segregation, recombination, and variation of these loci shaped the multicolored cocoons of domestic silkworms. This study revealed a new mechanism for flavonoids-based biological coloration that highlights the crucial role of gene duplication followed by functional diversification in acquiring new genetic functions; furthermore, the results in this work provide insight into phenotypic innovation during domestication.


Assuntos
Bombyx , Animais , Bombyx/genética , Bombyx/metabolismo , Seda/genética , Seda/metabolismo , Sequência de Bases , Flavonoides/metabolismo
8.
Clin Immunol ; 261: 109929, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38331303

RESUMO

Previous studies have shown that epigenetic factors are involved in the occurrence and development of rheumatoid arthritis (RA). However, the role of N6-methyladenosine (m6A) methylation in RA has not been determined. The aim of this study was to investigate the role and regulatory mechanisms of hypoxia-induced expression of the m6A demethylase alkB homolog 5 (ALKBH5) in RA fibroblast-like synoviocytes (FLSs). Synovial tissues were collected from RA and osteoarthritis (OA) patients, and RA FLSs were obtained. ALKBH5 expression in RA FLSs and collagen-induced arthritis (CIA) model rats was determined using quantitative reverse transcription-PCR (qRT-PCR), western blotting and immunohistochemistry (IHC). Using ALKBH5 overexpression and knockdown, we determined the role of ALKBH5 in RA FLS aggression and inflammation. The role of ALKBH5 in RA FLS regulation was explored using m6A-methylated RNA sequencing and methylated RNA immunoprecipitation coupled with quantitative real-time PCR. The expression of ALKBH5 was increased in RA synovial tissues, CIA model rats and RA FLSs, and a hypoxic environment increased the expression of ALKBH5 in FLSs. Increased expression of ALKBH5 promoted the proliferation and migration of RA-FLSs and inflammation. Conversely, decreased ALKBH5 expression inhibited the migration of RA-FLSs and inflammation. Mechanistically, hypoxia-induced ALKBH5 expression promoted FLS aggression and inflammation by regulating CH25H mRNA stability. Our study elucidated the functional roles of ALKBH5 and mRNA m6A methylation in RA and revealed that the HIF1α/2α-ALKBH5-CH25H pathway may be key for FLS aggression and inflammation. This study provides a novel approach for the treatment of RA by targeting the HIF1α/2α-ALKBH5-CH25H pathway.


Assuntos
Adenina/análogos & derivados , Agressão , Artrite Reumatoide , Humanos , Ratos , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Inflamação/metabolismo , Hipóxia , Fibroblastos/metabolismo , Proliferação de Células , Células Cultivadas , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
9.
Anal Chem ; 96(2): 810-820, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38173421

RESUMO

Monitoring mitochondrial esterase activity is crucial not only for investigating mitochondrial metabolism but also for assessing the effectiveness of mitochondrial-targeting prodrugs. However, accurately detecting esterase activity within mitochondria poses challenges due to its ubiquitous presence in cells and the uncontrolled localization of fluorogenic probes. To overcome this hurdle and reveal variations among different mitochondria, we isolated mitochondria and preserved their activity and functionality in a buffered environment. Subsequently, we utilized a laboratory-built nano-flow cytometer in conjunction with an esterase-responsive calcein-AM fluorescent probe to measure the esterase activity of individual mitochondria. This approach enabled us to investigate the influence of temperature, pH, metal ions, and various compounds on the mitochondrial esterase activity without any interference from other cellular constituents. Interestingly, we observed a decline in the mitochondrial esterase activity following the administration of mitochondrial respiratory chain inhibitors. Furthermore, we found that mitochondrial esterase activity was notably higher in the presence of a high concentration of ATP compared to that of ADP and AMP. Additionally, we noticed a correlation between elevated levels of complex IV and increased mitochondrial esterase activity. These findings suggest a functional connection between the mitochondrial respiratory chain and mitochondrial esterase activity. Moreover, we detected an upsurge in mitochondrial esterase activity during the early stages of apoptosis, while cellular esterase activity decreased. This highlights the significance of analyzing enzyme activity within specific organelle subregions. In summary, the integration of a nano-flow cytometer and fluorescent dyes introduces a novel method for quantifying mitochondrial enzyme activity with the potential to uncover the alterations and unique functions of other mitochondrial enzymes.


Assuntos
Corantes Fluorescentes , Mitocôndrias , Mitocôndrias/metabolismo , Corantes Fluorescentes/química , Apoptose , Membranas Mitocondriais , Esterases/metabolismo
10.
Small ; : e2402025, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766971

RESUMO

Aqueous aluminum ion batteries (AAIBs) possess the advantages of high safety, cost-effectiveness, eco-friendliness and high theoretical capacity. However, the Al2O3 film on the Al anode surface, a natural physical barrier to the plating of hydrated aluminum ions, is a key factor in the decomposition of the aqueous electrolyte and the severe hydrogen precipitation reaction. To circumvent the obnoxious Al anode, a proof-of-concept of an anode-free AAIB is first proposed, in which Al2TiO5, as a cathode pre-aluminum additive (Al source), can replenish Al loss by over cycling. The Al-Cu alloy layer, formed by plating Al on the Cu foil surface during the charge process, possesses a reversible electrochemical property and is paired with a polyaniline (cathode) to stimulate the battery to exhibit high initial discharge capacity (175 mAh g-1), high power density (≈410 Wh L-1) and ultra-long cycle life (4000 cycles) with the capacity retention of ≈60% after 1000 cycles. This work will act as a primer to ignite the enormous prospective researches on the anode-free aqueous Al ion batteries.

11.
J Transl Med ; 22(1): 499, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796415

RESUMO

BACKGROUND: Myocardial ischemia-reperfusion injury (MIRI) is caused by reperfusion after ischemic heart disease. LncRNA Snhg1 regulates the progression of various diseases. N6-methyladenosine (m6A) is the frequent RNA modification and plays a critical role in MIRI. However, it is unclear whether lncRNA Snhg1 regulates MIRI progression and whether the lncRNA Snhg1 was modified by m6A methylation. METHODS: Mouse cardiomyocytes HL-1 cells were utilized to construct the hypoxia/reoxygenation (H/R) injury model. HL-1 cell viability was evaluated utilizing CCK-8 method. Cell apoptosis, mitochondrial reactive oxygen species (ROS), and mitochondrial membrane potential (MMP) were quantitated utilizing flow cytometry. RNA immunoprecipitation and dual-luciferase reporter assays were applied to measure the m6A methylation and the interactions between lncRNA Snhg1 and targeted miRNA or target miRNAs and its target gene. The I/R mouse model was constructed with adenovirus expressing lncRNA Snhg1. HE and TUNEL staining were used to evaluate myocardial tissue damage and apoptosis. RESULTS: LncRNA Snhg1 was down-regulated after H/R injury, and overexpressed lncRNA Snhg1 suppressed H/R-stimulated cell apoptosis, mitochondrial ROS level and polarization. Besides, lncRNA Snhg1 could target miR-361-5p, and miR-361-5p targeted OPA1. Overexpressed lncRNA Snhg1 suppressed H/R-stimulated cell apoptosis, mitochondrial ROS level and polarization though the miR-361-5p/OPA1 axis. Furthermore, WTAP induced lncRNA Snhg1 m6A modification in H/R-stimulated HL-1 cells. Moreover, enforced lncRNA Snhg1 repressed I/R-stimulated myocardial tissue damage and apoptosis and regulated the miR-361-5p and OPA1 levels. CONCLUSION: WTAP-mediated m6A modification of lncRNA Snhg1 regulated MIRI progression through modulating myocardial apoptosis, mitochondrial ROS production, and mitochondrial polarization via miR-361-5p/OPA1 axis, providing the evidence for lncRNA as the prospective target for alleviating MIRI progression.


Assuntos
Apoptose , MicroRNAs , Dinâmica Mitocondrial , Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , RNA Longo não Codificante , Animais , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , MicroRNAs/metabolismo , MicroRNAs/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Camundongos , Apoptose/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Linhagem Celular , Masculino , Camundongos Endogâmicos C57BL , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética , Espécies Reativas de Oxigênio/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Sequência de Bases , Metilação , Potencial da Membrana Mitocondrial
12.
Acta Neuropathol ; 147(1): 13, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38194050

RESUMO

The development of the cerebral cortex involves a series of dynamic events, including cell proliferation and migration, which rely on the motor protein dynein and its regulators NDE1 and NDEL1. While the loss of function in NDE1 leads to microcephaly-related malformations of cortical development (MCDs), NDEL1 variants have not been detected in MCD patients. Here, we identified two patients with pachygyria, with or without subcortical band heterotopia (SBH), carrying the same de novo somatic mosaic NDEL1 variant, p.Arg105Pro (p.R105P). Through single-cell RNA sequencing and spatial transcriptomic analysis, we observed complementary expression of Nde1/NDE1 and Ndel1/NDEL1 in neural progenitors and post-mitotic neurons, respectively. Ndel1 knockdown by in utero electroporation resulted in impaired neuronal migration, a phenotype that could not be rescued by p.R105P. Remarkably, p.R105P expression alone strongly disrupted neuronal migration, increased the length of the leading process, and impaired nucleus-centrosome coupling, suggesting a failure in nucleokinesis. Mechanistically, p.R105P disrupted NDEL1 binding to the dynein regulator LIS1. This study identifies the first lissencephaly-associated NDEL1 variant and sheds light on the distinct roles of NDE1 and NDEL1 in nucleokinesis and MCD pathogenesis.


Assuntos
Lisencefalia , Humanos , Lisencefalia/genética , Movimento Celular/genética , Proliferação de Células , Córtex Cerebral , Dineínas/genética , Proteínas de Transporte , Proteínas Associadas aos Microtúbulos/genética
13.
Virol J ; 21(1): 123, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822405

RESUMO

BACKGROUND: Long coronavirus disease (COVID) after COVID-19 infection is continuously threatening the health of people all over the world. Early prediction of the risk of Long COVID in hospitalized patients will help clinical management of COVID-19, but there is still no reliable and effective prediction model. METHODS: A total of 1905 hospitalized patients with COVID-19 infection were included in this study, and their Long COVID status was followed up 4-8 weeks after discharge. Univariable and multivariable logistic regression analysis were used to determine the risk factors for Long COVID. Patients were randomly divided into a training cohort (70%) and a validation cohort (30%), and factors for constructing the model were screened using Lasso regression in the training cohort. Visualize the Long COVID risk prediction model using nomogram. Evaluate the performance of the model in the training and validation cohort using the area under the curve (AUC), calibration curve, and decision curve analysis (DCA). RESULTS: A total of 657 patients (34.5%) reported that they had symptoms of long COVID. The most common symptoms were fatigue or muscle weakness (16.8%), followed by sleep difficulties (11.1%) and cough (9.5%). The risk prediction nomogram of age, diabetes, chronic kidney disease, vaccination status, procalcitonin, leukocytes, lymphocytes, interleukin-6 and D-dimer were included for early identification of high-risk patients with Long COVID. AUCs of the model in the training cohort and validation cohort are 0.762 and 0.713, respectively, demonstrating relatively high discrimination of the model. The calibration curve further substantiated the proximity of the nomogram's predicted outcomes to the ideal curve, the consistency between the predicted outcomes and the actual outcomes, and the potential benefits for all patients as indicated by DCA. This observation was further validated in the validation cohort. CONCLUSIONS: We established a nomogram model to predict the long COVID risk of hospitalized patients with COVID-19, and proved its relatively good predictive performance. This model is helpful for the clinical management of long COVID.


Assuntos
COVID-19 , Nomogramas , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/complicações , COVID-19/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Estudos de Coortes , Idoso , Adulto , Hospitalização/estatística & dados numéricos , Medição de Risco , Síndrome de COVID-19 Pós-Aguda
14.
Biotechnol Bioeng ; 121(5): 1642-1658, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38381097

RESUMO

Bacillus licheniformis formulations are effective for environmental remediation, gut microbiota modulation, and soil improvement. An adequate spore quantity is crucial for the activity of B. licheniformis formulations. This study investigated the synergistic effects of carbon/nitrogen source consumption and concentration on B. licheniformis BF-002 cultivation, with the aim of developing an automatic co-feeding strategy to enhance spore production. Initial glucose (10 g/L) and amino nitrogen (1.5 g/L) concentrations promote cell growth, followed by reduced glucose (2.0 g/L) and amino nitrogen (0.5 g/L) concentrations for sustained spore generation. The spore quantity reached 2.59 × 1010 CFU/mL. An automatic co-feeding strategy was developed and implemented in 5 and 50 L cultivations, resulting in spore quantities of 2.35 × 1010 and 2.86 × 1010 CFU/mL, respectively, improving by 6.81% and 30.00% compared to that with a fixed glucose concentration (10.0 g/L). The culture broth obtained at both the 5 and 50 L scales was spray-dried, resulting in bacterial powder with cell viability rates of 85.94% and 82.68%, respectively. Even after exposure to harsh conditions involving high temperature and humidity, cell viability remained at 72.80% and 69.89%, respectively. Employing the automatic co-feeding strategy increased the transcription levels of the spore formation-related genes spo0A, spoIIGA, bofA, and spoIV by 7.42%, 8.46%, 8.87%, and 9.79%, respectively. The proposed strategy effectively promoted Bacillus growth and spore formation, thereby enhancing the quality of B. licheniformis formulations.


Assuntos
Bacillus licheniformis , Bacillus , Carbono , Nitrogênio , Esporos Bacterianos , Bacillus/genética , Bacillus licheniformis/genética , Glucose
15.
Nitric Oxide ; 147: 1-5, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38547960

RESUMO

Endotoxin tolerance (ET) is the hyporesponsiveness to lipopolysaccharide (LPS) after prior exposure. It is characterized by the downregulation of pro-inflammatory cytokine levels. Although ET protects against inflammation, its abolishment or recovery is critical for immunity. Nitric oxide (NO) plays various roles in the development of ET; however, its specific role in ET recovery remains unknown. To induce ET, RAW264.7 cells (a murine macrophage cell line) were pre-exposed to LPS (LPS1, 100 ng/mL for 24 h) and subsequently re-stimulated with LPS (LPS2, 100 ng/mL for 24 h). Expression of cytokines, NO, nitrite and inducible NO synthase (iNOS) were measured after 0, 12, 24, and 36 h of resting after LPS1 treatment with or without the iNOS-specific inhibitor, 1400W. LPS2-induced tumor necrosis factor-⍺ (TNF-⍺) and interleukin-6 (IL-6) were downregulated after LPS1 treatment, confirming the development of ET. Notably, TNF-⍺ and IL-6 levels spontaneously rebounded after 12-24 h of resting following LPS1 treatment. In contrast, levles of NO, nitrite and iNOS increased during ET development and decreased during ET recovery. Moreover, 1400W inhibited ET development and blocked the early production of NO (<12 h) during ET recovery. Our findings suggest a negative correlation between iNOS-induced NO and cytokine levels in the abolishment of ET.


Assuntos
Lipopolissacarídeos , Óxido Nítrico Sintase Tipo II , Óxido Nítrico , Fator de Necrose Tumoral alfa , Animais , Óxido Nítrico/metabolismo , Camundongos , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Interleucina-6/metabolismo , Endotoxinas/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo
16.
Pharmacol Res ; : 107275, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908615

RESUMO

Triptolide (TP) is the principal bioactive compound of Tripterygium wilfordii with significant anti-tumor, anti-inflammatory and immunosuppressive activities. However, its severe hepatotoxicity greatly limits its clinical use. The underlying mechanism of TP-induced liver damage is still poorly understood. Here, we estimate the role of the gut microbiota in TP hepatotoxicity and investigate the bile acid metabolism mechanisms involved. The results of the antibiotic cocktail (ABX) and fecal microbiota transplantation (FMT) experiment demonstrate the involvement of intestinal flora in TP hepatotoxicity. Moreover, TP treatment significantly perturbed gut microbial composition and reduced the relative abundances of Lactobacillus rhamnosus GG (LGG). Supplementation with LGG reversed TP-induced hepatotoxicity by increasing bile salt hydrolase (BSH) activity and reducing the increased conjugated bile acids (BA). LGG supplementation upregulates hepatic FXR expression and inhibits NLRP3 inflammasome activation in TP-treated mice. In summary, this study found that gut microbiota is involved in TP hepatotoxicity. LGG supplementation protects mice against TP-induced liver damage. The underlying mechanism was associated with the gut microbiota-BA-FXR axis. Therefore, LGG holds the potential to prevent and treat TP hepatotoxicity in the clinic.

17.
Clin Exp Rheumatol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38855955

RESUMO

OBJECTVES: Among immunosuppressants, rituximab is most strongly associated with the risk of hepatitis B virus (HBV) reactivation in chronic HBV individuals. Current guidelines recommending antiviral prophylaxis for these patients on rituximab are predominantly based on studies in oncology. However, limited data existed for the precise risk of HBV flares, effectiveness and optimal duration of antiviral prophylaxis in rituximab-treated rheumatic patients, whose immune status and treatment regimen differ significantly from those of oncology patients. Therefore, we aimed to assess the incidence and clinical outcome of HBV reactivation in HBsAg-positive patients receiving rituximab for various autoimmune diseases who discontinue the antiviral agents. METHODS: A retrospective analysis was performed on 95 hepatitis B surface antigen (HBsAg)-positive patients treated with rituximab for autoimmune diseases in a single centre in Taiwan. HBV related hepatitis, defined as alanine aminotransferase (ALT) more than 3 times of baseline level and concurrent HBV reactivation, after anti-viral discontinuation, was the primary endpoint. Factors associated with HBV hepatitis flare and off-antiviral hepatitis flare were also analysed. RESULTS: With nucleos(t)ide analogues (NA) prophylaxis, no hepatitis flares occurred. However, without prophylaxis, 59% had flare (24.5 per 100 person-years) and 8% experienced liver decompensation. Concurrent steroid use was a dose-dependent risk factor for flare. After NA discontinuation, rituximab "retreatment" led to flares in 75% of cases and liver decompensation in 63% of patients. Stopping NAs within one-year post-rituximab, even without further rituximab treatment, resulted in a 38% flare rate. CONCLUSIONS: This study offers the direct evidence for the necessity of universal antiviral prophylaxis in rheumatic patients with chronic HBV receiving rituximab. After NA discontinuation, rituximab "retreatment" led to even higher flare rate and worse outcome. Patients who completed rituximab treatment should also keep antiviral agents for at least one more year to prevent hepatitis flare.

18.
Phys Chem Chem Phys ; 26(20): 14538-14546, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38715520

RESUMO

Metal-doped nitrogen clusters serve as effective models for elucidating the geometries and electronic properties of nitrogen-rich compounds at the molecular scale. Herein, we have conducted a systematic study of VIB-group metal chromium (Cr) doped nitrogen clusters through a combination of mass spectrometry techniques and density functional theory (DFT) calculations. The laser ablation is employed to generate CrNn+ clusters. The results reveal that CrN8+ cluster exhibits the highest signal intensity in mass spectrometry. The photodissociation experiments with 266 nm photons confirm that the chromium heteroazide clusters are composed of chromium ions and N2 molecules. Further structural searches and electronic structure calculations indicate that the cationic CrN8+ cluster possesses an X shaped geometry with D2 symmetry and exhibits robust stability. Molecular orbital and chemical bonding analyses demonstrate the existence of strong interactions between Cr+ cation and N2 ligands. The present findings enrich the geometries of metal doped nitrogen clusters and provide valuable guidance for the rational design and synthesis of novel transition metal nitrides.

19.
BMC Cardiovasc Disord ; 24(1): 199, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582861

RESUMO

BACKGROUND: The study set out to develop an accurate and clinically valuable prognostic nomogram to assess the risk of in-hospital death in patients with acute decompensated chronic heart failure (ADCHF) and diabetes. METHODS: We extracted clinical data of patients diagnosed with ADCHF and diabetes from the Medical Information Mart for Intensive Care III database. Risk variables were selected utilizing least absolute shrinkage and selection operator regression analysis, and were included in multivariate logistic regression and presented in nomogram. bootstrap was used for internal validation. The discriminative power and predictive accuracy of the nomogram were estimated using the area under the receiver operating characteristic curve (AUC), calibration curve and decision curve analysis (DCA). RESULTS: Among 867 patients with ADCHF and diabetes, In-hospital death occurred in 81 (9.3%) patients. Age, heart rate, systolic blood pressure, red blood cell distribution width, shock, ß-blockers, angiotensin converting enzyme inhibitors or angiotensin receptor blockers, assisted ventilation, and blood urea nitrogen were brought into the nomogram model. The calibration curves suggested that the nomogram was well calibrated. The AUC of the nomogram was 0.873 (95% CI: 0.834-0.911), which was higher that of the Simplified Acute Physiology Score II [0.761 (95% CI: 0.711-0.810)] and sequential organ failure assessment score [0.699 (95% CI: 0.642-0.756)], and Guidelines-Heart Failure score [0.782 (95% CI: 0.731-0.835)], indicating that the nomogram had better ability to predict in-hospital mortality. In addition, the internally validated C-index was 0.857 (95% CI: 0.825-0.891), which again verified the validity of this model. CONCLUSIONS: This study constructed a simple and accurate nomogram for predicting in-hospital mortality in patients with ADCHF and diabetes, especially in those who admitted to the intensive care unit for more than 48 hours, which contributed clinicians to assess the risk and individualize the treatment of patients, thereby reducing in-hospital mortality.


Assuntos
Diabetes Mellitus , Insuficiência Cardíaca , Humanos , Nomogramas , Mortalidade Hospitalar , Unidades de Terapia Intensiva , Diabetes Mellitus/diagnóstico , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Estudos Retrospectivos
20.
Bioorg Chem ; 143: 107054, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157670

RESUMO

Atopic dermatitis (AD) is a common inflammatory disease and it is very difficult to treat. In the present work, a series of costunolide derivatives have been prepared, and in vitro and in vivo anti-inflammatory activities have evaluated. The results showed that most derivatives displayed good inhibition of NO generation with low cytotoxicity, and 7d could inhibit the phosphorylation of P38, P65 NF-κB and IκB-α in LPS-induced RAW264.7 model. The in vivo researches showed that 7d could improve skin injury symptoms, decrease Th2-type cytokine levels, inhibit HIS levels, alleviate scratching and repaire the damaged skin barrier through the inhibition of phosphorylation of MAPK and NF-κB signaling pathways on MC903-induced AD model. Therefore, costunolide derivatives may be new potent anti-AD agents for further study.


Assuntos
Dermatite Atópica , Sesquiterpenos , Anti-Inflamatórios/efeitos adversos , Citocinas/metabolismo , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/induzido quimicamente , Lipopolissacarídeos/efeitos adversos , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células RAW 264.7 , Camundongos , Animais
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