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1.
Nature ; 616(7955): 113-122, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36922587

RESUMO

Emerging spatial technologies, including spatial transcriptomics and spatial epigenomics, are becoming powerful tools for profiling of cellular states in the tissue context1-5. However, current methods capture only one layer of omics information at a time, precluding the possibility of examining the mechanistic relationship across the central dogma of molecular biology. Here, we present two technologies for spatially resolved, genome-wide, joint profiling of the epigenome and transcriptome by cosequencing chromatin accessibility and gene expression, or histone modifications (H3K27me3, H3K27ac or H3K4me3) and gene expression on the same tissue section at near-single-cell resolution. These were applied to embryonic and juvenile mouse brain, as well as adult human brain, to map how epigenetic mechanisms control transcriptional phenotype and cell dynamics in tissue. Although highly concordant tissue features were identified by either spatial epigenome or spatial transcriptome we also observed distinct patterns, suggesting their differential roles in defining cell states. Linking epigenome to transcriptome pixel by pixel allows the uncovering of new insights in spatial epigenetic priming, differentiation and gene regulation within the tissue architecture. These technologies are of great interest in life science and biomedical research.


Assuntos
Cromatina , Epigenoma , Mamíferos , Transcriptoma , Animais , Humanos , Camundongos , Cromatina/genética , Cromatina/metabolismo , Epigênese Genética , Epigenômica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Mamíferos/genética , Histonas/química , Histonas/metabolismo , Análise de Célula Única , Especificidade de Órgãos , Encéfalo/embriologia , Encéfalo/metabolismo , Envelhecimento/genética
2.
Nature ; 623(7986): 432-441, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37914932

RESUMO

Chromatin accessibility is essential in regulating gene expression and cellular identity, and alterations in accessibility have been implicated in driving cancer initiation, progression and metastasis1-4. Although the genetic contributions to oncogenic transitions have been investigated, epigenetic drivers remain less understood. Here we constructed a pan-cancer epigenetic and transcriptomic atlas using single-nucleus chromatin accessibility data (using single-nucleus assay for transposase-accessible chromatin) from 225 samples and matched single-cell or single-nucleus RNA-sequencing expression data from 206 samples. With over 1 million cells from each platform analysed through the enrichment of accessible chromatin regions, transcription factor motifs and regulons, we identified epigenetic drivers associated with cancer transitions. Some epigenetic drivers appeared in multiple cancers (for example, regulatory regions of ABCC1 and VEGFA; GATA6 and FOX-family motifs), whereas others were cancer specific (for example, regulatory regions of FGF19, ASAP2 and EN1, and the PBX3 motif). Among epigenetically altered pathways, TP53, hypoxia and TNF signalling were linked to cancer initiation, whereas oestrogen response, epithelial-mesenchymal transition and apical junction were tied to metastatic transition. Furthermore, we revealed a marked correlation between enhancer accessibility and gene expression and uncovered cooperation between epigenetic and genetic drivers. This atlas provides a foundation for further investigation of epigenetic dynamics in cancer transitions.


Assuntos
Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias , Humanos , Hipóxia Celular , Núcleo Celular , Cromatina/genética , Cromatina/metabolismo , Elementos Facilitadores Genéticos/genética , Epigênese Genética/genética , Transição Epitelial-Mesenquimal , Estrogênios/metabolismo , Perfilação da Expressão Gênica , Proteínas Ativadoras de GTPase/metabolismo , Metástase Neoplásica , Neoplasias/classificação , Neoplasias/genética , Neoplasias/patologia , Sequências Reguladoras de Ácido Nucleico/genética , Análise de Célula Única , Fatores de Transcrição/metabolismo
3.
Nat Chem Biol ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039256

RESUMO

Growing resistance toward ribosome-targeting macrolide antibiotics has limited their clinical utility and urged the search for superior compounds. Macrolones are synthetic macrolide derivatives with a quinolone side chain, structurally similar to DNA topoisomerase-targeting fluoroquinolones. While macrolones show enhanced activity, their modes of action have remained unknown. Here, we present the first structures of ribosome-bound macrolones, showing that the macrolide part occupies the macrolide-binding site in the ribosomal exit tunnel, whereas the quinolone moiety establishes new interactions with the tunnel. Macrolones efficiently inhibit both the ribosome and DNA topoisomerase in vitro. However, in the cell, they target either the ribosome or DNA gyrase or concurrently both of them. In contrast to macrolide or fluoroquinolone antibiotics alone, dual-targeting macrolones are less prone to select resistant bacteria carrying target-site mutations or to activate inducible macrolide resistance genes. Furthermore, because some macrolones engage Erm-modified ribosomes, they retain activity even against strains with constitutive erm resistance genes.

4.
Nano Lett ; 24(14): 4150-4157, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38529926

RESUMO

Metallic Zn is considered as a promising anode material because of its abundance, eco-friendliness, and high theoretical capacity. However, the uncontrolled dendrite growth and side reactions restrict its further practical application. Herein, we proposed a ß-cyclodextrin-modified multiwalled carbon nanotube (CD-MWCNT) layer for Zn metal anodes. The obtained CD-MWCNT layer with high affinity to Zn can significantly reduce the transfer barrier of Zn2+ at the electrode/electrolyte interface, facilitating the uniform deposition of Zn2+ and suppressing water-caused side reactions. Consequently, the Zn||Zn symmetric cell assembled with CD-MWCNT shows a significantly enhanced cycling durability, maintaining a cycling life exceeding 1000 h even under a high current density of 5 mA cm-2. Furthermore, the full battery equipped with a V2O5 cathode displays an unparalleled long life. This work unveils a promising avenue toward the achievement of high-performance Zn metal anodes.

5.
EMBO J ; 39(16): e103631, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32643828

RESUMO

Priming of synaptic vesicles involves Munc13-catalyzed transition of the Munc18-1/syntaxin-1 complex to the SNARE complex in the presence of SNAP-25 and synaptobrevin-2; Munc13 drives opening of syntaxin-1 via the MUN domain while Munc18-1 primes SNARE assembly via domain 3a. However, the underlying mechanism remains unclear. In this study, we have identified a number of residues in domain 3a of Munc18-1 that are crucial for Munc13 and Munc18-1 actions in SNARE complex assembly and synaptic vesicle priming. Our results showed that two residues (Q301/K308) at the side of domain 3a mediate the interaction between the Munc18-1/syntaxin-1 complex and the MUN domain. This interaction enables the MUN domain to drive the opening of syntaxin-1 linker region, thereby leading to the extension of domain 3a and promoting synaptobrevin-2 binding. In addition, we identified two residues (K332/K333) at the bottom of domain 3a that mediate the interaction between Munc18-1 and the SNARE motif of syntaxin-1. This interaction ensures Munc18-1 to persistently associate with syntaxin-1 during the conformational change of syntaxin-1 from closed to open, which reinforces the role of Munc18-1 in templating SNARE assembly. Taken together, our data suggest a mechanism by which Munc13 activates the Munc18-1/syntaxin-1 complex and enables Munc18-1 to prime SNARE assembly.


Assuntos
Proteínas Munc18 , Proteínas do Tecido Nervoso , Proteínas SNARE , Membranas Sinápticas , Sintaxina 1 , Animais , Células HEK293 , Humanos , Camundongos , Proteínas Munc18/química , Proteínas Munc18/genética , Proteínas Munc18/metabolismo , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Domínios Proteicos , Ratos , Proteínas SNARE/química , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Membranas Sinápticas/química , Membranas Sinápticas/genética , Membranas Sinápticas/metabolismo , Sintaxina 1/química , Sintaxina 1/genética , Sintaxina 1/metabolismo
6.
BMC Med ; 22(1): 171, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38649992

RESUMO

BACKGROUND: Little is known about the safety and efficacy of discontinuing antiplatelet therapy via LMWH bridging therapy in elderly patients with coronary stents implanted for > 12 months undergoing non-cardiac surgery. This randomized trial was designed to compare the clinical benefits and risks of antiplatelet drug discontinuation via LMWH bridging therapy. METHODS: Patients were randomized 1:1 to receive subcutaneous injections of either dalteparin sodium or placebo. The primary efficacy endpoint was cardiac or cerebrovascular events. The primary safety endpoint was major bleeding. RESULTS: Among 2476 randomized patients, the variables (sex, age, body mass index, comorbidities, medications, and procedural characteristics) and percutaneous coronary intervention information were not significantly different between the bridging and non-bridging groups. During the follow-up period, the rate of the combined endpoint in the bridging group was significantly lower than in the non-bridging group (5.79% vs. 8.42%, p = 0.012). The incidence of myocardial injury in the bridging group was significantly lower than in the non-bridging group (3.14% vs. 5.19%, p = 0.011). Deep vein thrombosis occurred more frequently in the non-bridging group (1.21% vs. 0.4%, p = 0.024), and there was a trend toward a higher rate of pulmonary embolism (0.32% vs. 0.08%, p = 0.177). There was no significant difference between the groups in the rates of acute myocardial infarction (0.81% vs. 1.38%), cardiac death (0.24% vs. 0.41%), stroke (0.16% vs. 0.24%), or major bleeding (1.22% vs. 1.45%). Multivariable analysis showed that LMWH bridging, creatinine clearance < 30 mL/min, preoperative hemoglobin < 10 g/dL, and diabetes mellitus were independent predictors of ischemic events. LMWH bridging and a preoperative platelet count of < 70 × 109/L were independent predictors of minor bleeding events. CONCLUSIONS: This study showed the safety and efficacy of perioperative LMWH bridging therapy in elderly patients with coronary stents implanted > 12 months undergoing non-cardiac surgery. An alternative approach might be the use of bridging therapy with half-dose LMWH. TRIAL REGISTRATION: ISRCTN65203415.


Assuntos
Stents , Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/uso terapêutico , Inibidores da Agregação Plaquetária/efeitos adversos , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/uso terapêutico , Heparina de Baixo Peso Molecular/efeitos adversos , Dalteparina/administração & dosagem , Dalteparina/uso terapêutico , Dalteparina/efeitos adversos , Resultado do Tratamento , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Hemorragia/induzido quimicamente , Placebos/administração & dosagem , Assistência Perioperatória/métodos
7.
Appl Environ Microbiol ; 90(8): e0071724, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39016615

RESUMO

Mechanistic investigations are of paramount importance in elucidating the modes of action of antibiotics and facilitating the discovery of novel drugs. We reported a luciferase-based reporter system using bacterial cells to unveil mechanisms of antimicrobials targeting transcription and translation. The reporter gene Nluc encoding NanoLuciferase (NanoLuc) was integrated into the genome of the Gram-positive model organism, Bacillus subtilis, to generate a reporter strain BS2019. Cellular transcription and translation levels were assessed by quantifying the amount of Nluc mRNA as well as the luminescence catalyzed by the enzyme NanoLuc. We validated this system using three known inhibitors of transcription (rifampicin), translation (chloramphenicol), and cell wall synthesis (ampicillin). The B. subtilis reporter strain BS2019 successfully revealed a decline in Nluc expression by rifampicin and NanoLuc enzyme activity by chloramphenicol, while ampicillin produced no observable effect. The assay was employed to characterize a previously discovered bacterial transcription inhibitor, CUHK242, with known antimicrobial activity against drug-resistant Staphylococcus aureus. Production of Nluc mRNA in our reporter BS2019 was suppressed in the presence of CUHK242, demonstrating the usefulness of the construct, which provides a simple way to study the mechanism of potential antibiotic candidates at early stages of drug discovery. The reporter system can also be modified by adopting different promoters and reporter genes to extend its scope of contribution to other fields of work. IMPORTANCE: Discovering new classes of antibiotics is desperately needed to combat the emergence of multidrug-resistant pathogens. To facilitate the drug discovery process, a simple cell-based assay for mechanistic studies is essential to characterize antimicrobial candidates. In this work, we developed a luciferase-based reporter system to quantify the transcriptional and translational effects of potential compounds and validated our system using two currently marketed drugs. Reporter strains generated in this study provide readily available means for identifying bacterial transcription inhibitors as prospective novel antibacterials. We also provided a series of plasmids for characterizing promoters under various conditions such as stress.


Assuntos
Antibacterianos , Bacillus subtilis , Genes Reporter , Luciferases , Bacillus subtilis/genética , Bacillus subtilis/efeitos dos fármacos , Antibacterianos/farmacologia , Luciferases/genética , Testes de Sensibilidade Microbiana
8.
Epidemiology ; 35(4): 559-567, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38534181

RESUMO

BACKGROUND: Artificial light at night, a well-recognized circadian clock disrupter, causes disturbances in endocrine homeostasis. However, the association of artificial light at night with polycystic ovary syndrome (PCOS) is still unknown. This study examines the effects of outdoor artificial light at night on sex hormones, glucose homeostasis markers, and PCOS prevalence in Anhui Province, China. METHODS: We recruited 20,633 women of reproductive age from Anhui Medical University Reproductive Medicine Center. PCOS was diagnosed according to Rotterdam criteria. We estimated long-term (previous year) and short-term (previous month) artificial light at night values for residential addresses using 500 m resolution satellite imagery. We fitted multivariable models, using both linear and logistic regression, to estimate the association of artificial light at night with sex hormones, glucose homeostasis markers, and PCOS prevalence. RESULTS: Both long-term and short-term exposure to outdoor artificial light at night were negatively associated with follicle-stimulating hormone and luteinizing hormone levels, while positively associated with testosterone, fasting insulin, homeostasis model assessment-insulin resistance, and homeostasis model assessment-insulin resistance-ß levels. The second-highest quintile of artificial light at night was associated with increased PCOS prevalence (odds ratio [OR long-term ] = 1.4; 95% confidence interval [CI] = 1.2, 1.6 and OR short-term = 1.3; 95% CI = 1.1, 1.5) compared with the lowest quintile. In addition, prevalence of PCOS was linearly associated with long-term exposure to artificial light at night, but nonlinearly associated with short-term exposure. This association was more evident in younger, obese or overweight, moderately educated, rural women, and for the summer and fall seasons. CONCLUSION: Outdoor artificial light at night may be a novel risk factor for PCOS.


Assuntos
Hormônio Foliculoestimulante , Homeostase , Resistência à Insulina , Hormônio Luteinizante , Síndrome do Ovário Policístico , Humanos , Feminino , Síndrome do Ovário Policístico/epidemiologia , Adulto , China/epidemiologia , Hormônio Luteinizante/sangue , Adulto Jovem , Hormônio Foliculoestimulante/sangue , Glicemia/análise , Iluminação/efeitos adversos , Testosterona/sangue , Prevalência , Adolescente , Insulina/sangue , Modelos Logísticos
9.
Cardiovasc Diabetol ; 23(1): 108, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553738

RESUMO

BACKGROUND: Coronary inflammation plays crucial role in type 2 diabetes mellitus (T2DM) induced cardiovascular complications. Both glucose-lowering drug interventions (GLDIS) and glycemic control (GC) status potentially correlate coronary inflammation, as indicated by changes in pericoronary adipose tissue (PCAT) attenuation, and thus influence cardiovascular risk. This study evaluated the impact of GLDIS and GC status on PCAT attenuation in T2DM patients. METHODS: This retrospective study collected clinical data and coronary computed tomography angiography (CCTA) images of 1,342 patients, including 547 T2DM patients and 795 non-T2DM patients in two tertiary hospitals. T2DM patients were subgroup based on two criteria: (1) GC status: well: HbA1c < 7%, moderate: 7 ≤ HbA1c ≤ 9%, and poor: HbA1c > 9%; (2) GLDIS and non-GLDIS. PCAT attenuations of the left anterior descending artery (LAD-PCAT), left circumflex artery (LCX-PCAT), and right coronary artery (RCA-PCAT) were measured. Propensity matching (PSM) was used to cross compare PCAT attenuation of non-T2DM and all subgroups of T2DM patients. Linear regressions were conducted to evaluate the impact of GC status and GLDIS on PCAT attenuation in T2DM patients. RESULTS: Significant differences were observed in RCA-PCAT and LCX-PCAT between poor GC-T2DM and non-T2DM patients (LCX: - 68.75 ± 7.59 HU vs. - 71.93 ± 7.25 HU, p = 0.008; RCA: - 74.37 ± 8.44 HU vs. - 77.2 ± 7.42 HU, p = 0.026). Higher PCAT attenuation was observed in LAD-PCAT, LCX-PCAT, and RCA-PCAT in non-GLDIS T2DM patients compared with GLDIS T2DM patients (LAD: - 78.11 ± 8.01 HU vs. - 75.04 ± 8.26 HU, p = 0.022; LCX: - 71.10 ± 8.13 HU vs. - 68.31 ± 7.90 HU, p = 0.037; RCA: - 78.17 ± 8.64 HU vs. - 73.35 ± 9.32 HU, p = 0.001). In the linear regression, other than sex and duration of diabetes, both metformin and acarbose were found to be significantly associated with lower LAD-PCAT (metformin: ß coefficient = - 2.476, p=0.021; acarbose: ß coefficient = - 1.841, p = 0.031). CONCLUSION: Inadequate diabetes management, including poor GC and lack of GLDIS, may be associated with increased coronary artery inflammation in T2DM patients, as indicated by PCAT attenuation on CCTA, leading to increased cardiovascular risk. This finding could help healthcare providers identify T2DM patients with increased cardiovascular risk, develop improved cardiovascular management programs, and reduce subsequent cardiovascular related mortality.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Metformina , Placa Aterosclerótica , Humanos , Angiografia Coronária/métodos , Estudos Retrospectivos , Tecido Adiposo Epicárdico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Acarbose , Hemoglobinas Glicadas , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Angiografia por Tomografia Computadorizada/métodos , Tecido Adiposo/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem
10.
Toxicol Appl Pharmacol ; 492: 117118, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39362309

RESUMO

Bisphenol A (BPA) is among the extensively researched environmental endocrine-disrupting chemicals (EDCs), and its utilization is restricted owing to the detrimental impacts it has on human health. Bisphenol AP (BPAP) is one of the alternatives to BPA, but the influence of BPAP on human health has not been elucidated. The objective of the current research was to determine the influence of BPAP exposure on the in vitro maturation of mouse oocytes and to explore its potential reproductive toxicity. BPAP exposure was found to inhibit polar body extrusion during mouse oocyte maturation, resulting in an arrest at the metaphase I stage of meiosis. Exposure to BPAP led to sustained activation of BubR1, preventing the degradation of both Securin and Cyclin B1. Mechanistically, BPAP exposure disrupts spindle assembly and chromosome alignment. Levels of acetylated α-tubulin were significantly elevated in BPAP-treated oocytes, reflecting decreased spindle stability. Exposure to BPAP also induced DNA damage and impaired DNA damage repair. In addition, BPAP exposure altered histone modification levels. In summary, this investigation suggests that exposure to BPAP can influence cytoskeletal assembly, interfere with cell cycle progression, induce DNA damage, alter histone modifications, and ultimately impede oocyte meiotic maturation. This investigation enhances understanding of the impact of bisphenol analogs on female gametes, underscoring that BPAP cannot be considered a reliable replacement for BPA.

11.
J Appl Microbiol ; 135(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830792

RESUMO

AIMS: Cytidine, as an important commercial precursor in the chemical synthesis of antiviral and antitumor drugs, is in great demand in the market. Therefore, the purpose of this study is to build a microbial cell factory with high cytidine production. METHODS AND RESULTS: A mutant E. coli NXBG-11-F34 with high tolerance to uridine monophosphate structural analogs and good genetic stability was obtained by atmospheric room temperature plasma (ARTP) mutagenesis combined with high-throughput screening. Then, the udk and rihA genes involved in cytidine catabolism were knocked out by CRISPR/Cas9 gene editing technology, and the recombinant strain E. coli NXBG-13 was constructed. The titer, yield, and productivity of cytidine fermented in a 5 l bioreactor were 15.7 g l-1, 0.164 g g-1, and 0.327 g l-1 h-1, respectively. Transcriptome analysis of the original strain and the recombinant strain E. coli NXBG-13 showed that the gene expression profiles of the two strains changed significantly, and the cytidine de novo pathway gene of the recombinant strain was up-regulated significantly. CONCLUSIONS: ARTP mutagenesis combined with metabolic engineering is an effective method to construct cytidine-producing strains.


Assuntos
Citidina , Escherichia coli , Engenharia Metabólica , Mutagênese , Escherichia coli/genética , Escherichia coli/metabolismo , Citidina/genética , Citidina/metabolismo , Gases em Plasma , Reatores Biológicos , Edição de Genes/métodos , Sistemas CRISPR-Cas , Fermentação , Temperatura
12.
Bioorg Chem ; 151: 107712, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39146761

RESUMO

Ketolides (3-keto) such as TE-802 and acylides (3-O-acyl) like TEA0929 are ineffective against constitutively resistant pathogens harboring erythromycin ribosomal methylation (erm) genes. Following our previous work on alkylides (3-O-alkyl), we explored the structure-activity relationships of hybrids combining (R/S) 3-descladinosyl erythromycin with 6/7-quinolone motifs, featuring extended ether-linked spacers, with a focus on their efficacy against pathogens bearing constitutive erm gene resistance. Optimized compounds 17a and 31f not only reinstated efficacy against inducibly resistant pathogens but also demonstrated significantly augmented activities against constitutively resistant strains of Streptococcus pneumoniae and Streptococcus pyogenes, which are typically refractory to existing C-3 modified macrolides. Notably, hybrid 31f (coded ZN-51) represented a pioneering class of agents distinguished by its dual modes of action, with ribosomes as the primary target and topoisomerases as the secondary target. As a novel chemotype of macrolide-quinolone hybrids, alkylide 31f is a valuable addition to our armamentarium against macrolide-resistant bacteria.


Assuntos
Antibacterianos , Macrolídeos , Testes de Sensibilidade Microbiana , Quinolonas , Streptococcus pneumoniae , Relação Estrutura-Atividade , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Quinolonas/química , Quinolonas/farmacologia , Quinolonas/síntese química , Macrolídeos/química , Macrolídeos/farmacologia , Streptococcus pneumoniae/efeitos dos fármacos , Estrutura Molecular , Desenho de Fármacos , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/enzimologia , Relação Dose-Resposta a Droga , Éteres/química , Éteres/farmacologia , Éteres/síntese química
13.
Bioorg Chem ; 143: 106983, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38016396

RESUMO

RNA polymerase is an essential enzyme involved in bacterial transcription, playing a crucial role in RNA synthesis. However, it requires the association with sigma factors to initiate this process. In our previous work, we utilized a structure-based drug discovery approach to create benzoyl and benzyl benzoic acid compounds. These compounds were designed based on the amino acid residues within the key binding site of sigma factors, which are crucial for their interaction with RNA polymerase. By inhibiting bacterial transcription, these compounds exhibited notable antimicrobial activity, and we coined them as sigmacidins to highlight their resemblance to sigma factors and the benzoic acid structure. In this study, we further modified the compound scaffolds and developed a series of sulfonamidyl benzoic acid derivatives. These derivatives displayed potent antimicrobial activity, with minimum inhibitory concentrations (MICs) as low as 1 µg/mL, demonstrating their efficacy against bacteria. Furthermore, these compounds demonstrated low cytotoxicity, indicating their potential as safe antimicrobial agents. To ascertain their mechanism of action in interfering with bacterial transcription, we conducted biochemical and cellular assays. Overall, this study showcases the effectiveness of sulfonamidyl benzoic acid derivatives as antimicrobial agents by targeting protein-protein interactions involving RNA polymerase and sigma factors. Their strong antimicrobial activity and low cytotoxicity implicate their potential in combating antibiotic-resistant bacteria.


Assuntos
Antibacterianos , Anti-Infecciosos , Antibacterianos/farmacologia , Antibacterianos/química , Fator sigma/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Bactérias/metabolismo , Ácido Benzoico/farmacologia , Testes de Sensibilidade Microbiana
14.
Environ Res ; 249: 118344, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38311200

RESUMO

More and more previously designed wastewater treatment plants (WWTPs) are upgraded to tertiary treatment to meet the higher effluent discharge standards of conventional pollutants. Contaminants of emerging concern (CECs) can cause adverse effects on organisms and usually flow into WWTPs along with urban sewage. How the retrofitted WWTPs targeting conventional pollutants will influence the treatment efficiency of CECs is seldom discussed. This study investigates the removal of CECs in two full-scale newly retrofitted WWTPs (CD and JM WWTPs), containing high-efficiency sedimentation tank and denitrification deep bed filter for enhancing total nitrogen removal. The overall CEC removal efficiencies in the CD and JM WWTPs were 73.79 % and 93.63 %, respectively. Mass balance results indicated that CD WWTP and JM WWTP release a total of 36.89 and 88.58 g/d of CECs into the environment through effluent and excess sludge, respectively. Analysis of the concentration of CECs along the treatment process revealed most CECs were removed in the biological treatment units. The incorporation of newly constructed tertiary treatment proved beneficial for CEC removal and removed 2.93 % and 2.36 % CECs, corresponding to CEC removal of 2.92 and 27.49 g/d in the CD and JM WWTPs, respectively. The data of this study were further used to evaluate the suitability of the SimpleTreat model for simulating the fate of CECs in WWTPs. The predicted fraction of CECs discharged through the biological treatment effluent were generally within ten-fold difference from the measured results, highlighting its potential for estimating CEC removal in WWTPs.


Assuntos
Nitrogênio , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Nitrogênio/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Águas Residuárias/análise
15.
Ecotoxicol Environ Saf ; 282: 116703, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38986335

RESUMO

3-methyl-4-nitrophenol (PNMC), a degradation product of organophosphorus insecticides and a byproduct of fuel combustion, exerting endocrine-disrupting effects. However, its impact on the meiotic process of oocytes remains unclear. In the present study, we investigated the effects of PNMC on meiotic maturation of mouse oocytes in vitro and related mechanisms. Morphologically, PNMC-exposure affected germinal vesicle breakdown (GVBD) and polar body extrusion (PBE) in mouse oocytes. Proteomic analysis suggested that PNMC-exposure altered oocyte protein expression that are associated with cytoskeleton, mitochondrial function and oxidative stress. Further studies demonstrated that PNMC-exposure disrupted spindle assembly and chromosome alignment, caused sustained activation of spindle assembly checkpoint (SAC), and arrested meiosis in oocytes. Specifically, PNMC-exposure interfered with the function of microtubule organizing centers (MTOCs) by significantly reducing phosphorylated mitogen activated protein kinase (p-MAPK) expression and disrupting the localization of Pericentrin and p-Aurora A, leading to spindle assembly failure. Besides, PNMC-exposure also increased α-tubulin acetylation, decreased microtubule stability. Moreover, PNMC-exposure impaired mitochondrial function, evidenced by abnormal mitochondrial distribution, decreased mitochondrial membrane potential and ATP levels, release of Cytochrome C into the cytoplasm, and elevated ROS levels. As a result, exposure to PNMC caused DNA damage and early apoptosis in oocytes. Fortunately, melatonin was able to promote oocyte maturation by removing the excessive ROS and enhancing mitochondrial function. These results highlight the adverse effects of PNMC on meiotic maturation, and underscore the protective role of melatonin against PNMC-induced damage.


Assuntos
Meiose , Melatonina , Mitocôndrias , Oócitos , Fuso Acromático , Animais , Oócitos/efeitos dos fármacos , Melatonina/farmacologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Feminino , Fuso Acromático/efeitos dos fármacos , Meiose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes , Inseticidas/toxicidade
16.
Ecotoxicol Environ Saf ; 276: 116312, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38608383

RESUMO

The use of bisphenol A (BPA) has been restricted due to its endocrine-disrupting effects. As a widely used alternative to BPA today, environmental levels of bisphenol Z (BPZ) continue to rise and accumulate in humans. Oocyte quality is critical for a successful pregnancy. Nevertheless, the toxic impacts of BPZ on the maturation of mammalian oocytes remain unexplored. Therefore, the impacts of BPZ and BPA on oocyte meiotic maturation were compared in an in vitro mouse oocyte culture model. Exposure to 150 µM of both BPZ and BPA disrupted the assembly of the meiotic spindle and the alignment of chromosomes, and BPZ exerted stronger toxicological effects than BPA. Furthermore, BPZ resulted in aberrant expression of F-actin, preventing the formation of the actin cap. Mechanistically, BPZ exposure disrupted the mitochondrial localization pattern, reduced mitochondrial membrane potential and ATP content, leading to impaired mitochondrial function. Further studies revealed that BPZ exposure resulted in oxidative stress and altered expression of genes associated with anti-oxidative stress. Moreover, BPZ induced severe DNA damage and triggered early apoptosis in oocytes, accompanied by impaired lysosomal function. Overall, the data in this study suggest that BPZ is not a safe alternative to BPA. BPZ can trigger early apoptosis by affecting mitochondrial function and causing oxidative stress and DNA damage in oocytes. These processes disrupt cytoskeletal assembly, arrest the cell cycle, and ultimately inhibit oocyte meiotic maturation.


Assuntos
Compostos Benzidrílicos , Dano ao DNA , Disruptores Endócrinos , Meiose , Mitocôndrias , Oócitos , Estresse Oxidativo , Fenóis , Animais , Fenóis/toxicidade , Oócitos/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Meiose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Feminino , Disruptores Endócrinos/toxicidade , Apoptose/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Actinas/metabolismo
17.
Ecotoxicol Environ Saf ; 284: 116915, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39178764

RESUMO

Fine particulate matter (PM2.5) may disrupt women's reproductive hormones, posing potential reproductive risks. However, the exact compositions of PM2.5 responsible for these effects remain unclear. Our investigation explored the long-term impacts of PM2.5 constituents on reproductive hormones, based on a large longitudinal assisted reproductive cohort study in Anhui, China. We included 24,396 reproductive hormone samples from 19,845 women attending assisted reproductive technologies (ART) between 2014 and 2020. Using high-resolution gridded data (1-km resolution), we calculated the residence-specified PM2.5 constituents during the year before the month of hormone testing. Relationships between PM2.5 constituents [organic matter (OM), chloride (Cl-), sulfate (SO42-), ammonium (NH4+), black carbon, and nitrate] and reproductive hormones were investigated using the linear mixed model with subject-specific intercepts. The constituent-proportion model and the constituent-residual model were also constructed. Additionally, cubic spline analysis was used to examine the potential non-linear exposure-response relationship. We found that per interquartile range (IQR) increment in OM was associated with a 5.31 % (3.74 %, 6.89 %) increase in estradiol, and per IQR increment in Cl- and NH4+ were associated with 13.56 % (7.63 %, 19.82 %) and 9.07 % (4.35 %, 14.01 %) increases in luteinizing hormone. Conversely, per IQR increment in OM and Cl- were associated with -7.27 % (-9.34 %, -5.16 %) and -8.52 % (-10.99 %, -5.98 %) decreases in progesterone, and per IQR increment in SO42- was associated with a -9.15 % (-10.31 %, -7.98 %) decrease in testosterone. These associations were held in both proportional and residual models. Moreover, exposure-response curves for estradiol and progesterone with PM2.5 constituents exhibited approximately U-shaped. These results suggested that specific PM2.5 constituents might disrupt reproductive hormone homeostasis in women attending ART, providing new evidence for formulating PM2.5 pollution reduction strategies that could benefit women's reproductive health.


Assuntos
Poluentes Atmosféricos , Estradiol , Material Particulado , Técnicas de Reprodução Assistida , Material Particulado/análise , Feminino , Humanos , Estudos Longitudinais , Adulto , China , Poluentes Atmosféricos/análise , Homeostase/efeitos dos fármacos , Progesterona , Exposição Ambiental , Hormônio Luteinizante
18.
BMC Biol ; 21(1): 158, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443000

RESUMO

BACKGROUND: Neurotransmitter release depends on the fusion of synaptic vesicles with the presynaptic membrane and is mainly mediated by SNARE complex assembly. During the transition of Munc18-1/Syntaxin-1 to the SNARE complex, the opening of the Syntaxin-1 linker region catalyzed by Munc13-1 leads to the extension of the domain 3a hinge loop, which enables domain 3a to bind SNARE motifs in Synaptobrevin-2 and Syntaxin-1 and template the SNARE complex assembly. However, the exact mechanism of domain 3a extension remains elusive. RESULTS: Here, we characterized residues on the domain 3a hinge loop that are crucial for the extension of domain 3a by using biophysical and biochemical approaches and electrophysiological recordings. We showed that the mutation of residues T323/M324/R325 disrupted Munc13-1-mediated SNARE complex assembly and membrane fusion starting from Munc18-1/Syntaxin-1 in vitro and caused severe defects in the synaptic exocytosis of mouse cortex neurons in vivo. Moreover, the mutation had no effect on the binding of Synaptobrevin-2 to isolated Munc18-1 or the conformational change of the Syntaxin-1 linker region catalyzed by the Munc13-1 MUN domain. However, the extension of the domain 3a hinge loop in Munc18-1/Syntaxin-1 was completely disrupted by the mutation, leading to the failure of Synaptobrevin-2 binding to Munc18-1/Syntaxin-1. CONCLUSIONS: Together with previous results, our data further support the model that the template function of Munc18-1 in SNARE complex assembly requires the extension of domain 3a, and particular residues in the domain 3a hinge loop are crucial for the autoinhibitory release of domain 3a after the MUN domain opens the Syntaxin-1 linker region.


Assuntos
Proteínas do Tecido Nervoso , Proteína 2 Associada à Membrana da Vesícula , Camundongos , Animais , Proteínas do Tecido Nervoso/genética , Proteína 2 Associada à Membrana da Vesícula/genética , Proteína 2 Associada à Membrana da Vesícula/metabolismo , Sintaxina 1/genética , Sintaxina 1/química , Sintaxina 1/metabolismo , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Proteínas SNARE/metabolismo , Ligação Proteica
19.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279241

RESUMO

We previously discovered WS-6 as a new antidepressant in correlation to its function of stimulating neurogenesis. Herein, several different scaffolds (stilbene, 1,3-diphenyl 1-propene, 1,3-diphenyl 2-propene, 1,2-diphenyl acrylo-1-nitrile, 1,2-diphenyl acrylo-2-nitrile, 1,3-diphenyl trimethylamine), further varied through substitutions of twelve amide substituents plus the addition of a methylene unit and an inverted amide, were examined to elucidate the SARs for promoting adult rat neurogenesis. Most of the compounds could stimulate proliferation of progenitors, but just a few chemicals possessing a specific structural profile, exemplified by diphenyl acrylonitrile 29b, 32a, and 32b, showed better activity than the clinical drug NSI-189 in promoting newborn cells differentiation into mature neurons. The most potent diphenyl acrylonitrile 32b had an excellent brain AUC to plasma AUC ratio (B/P = 1.6), suggesting its potential for further development as a new lead.


Assuntos
Acrilonitrila , Alcenos , Compostos de Bifenilo , Ratos , Animais , Acrilonitrila/farmacologia , Neurogênese , Hipocampo , Nitrilas/farmacologia , Amidas
20.
Angew Chem Int Ed Engl ; 63(20): e202402910, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38441480

RESUMO

The challenge of constructing a mechanically robust yet lightweight artificial solid-electrolyte interphase layer on lithium (Li) anodes highlights a trade-off between high battery safety and high energy density. Inspired by the intricate microstructure of the white sea urchin, we first develop a polyvinyl fluoride-hexafluoropropylene (PVDF-HFP) interfacial layer with a triple periodic minimal surface structure (TPMS) that could offer maximal modulus with minimal weight. This design endows high mechanical strength to an ordered porous structure, effectively reduces local current density, polarization, and internal resistance, and stabilizes the anode interface. At a low N/P ratio of ~3, using LiFePO4 as the cathode, Li anodes protected by TPMS-structured PVDF-HFP achieve an extremely low capacity-fading-rate of approximately 0.002 % per cycle over 200 cycles at 1 C, with an average discharge capacity of 142 mAh g-1. Meanwhile, the TPMS porous structure saves 50 wt % of the interfacial layer mass, thereby enhancing the energy density of the battery. The TPMS structure is conducive to large-scale additive manufacturing, which will provide a reference for the future development of lightweight, high-energy-density secondary batteries.

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