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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38555472

RESUMO

Predicting interactions between microbes and hosts plays critical roles in microbiome population genetics and microbial ecology and evolution. How to systematically characterize the sophisticated mechanisms and signal interplay between microbes and hosts is a significant challenge for global health risks. Identifying microbe-host interactions (MHIs) can not only provide helpful insights into their fundamental regulatory mechanisms, but also facilitate the development of targeted therapies for microbial infections. In recent years, computational methods have become an appealing alternative due to the high risk and cost of wet-lab experiments. Therefore, in this study, we utilized rich microbial metagenomic information to construct a novel heterogeneous microbial network (HMN)-based model named KGVHI to predict candidate microbes for target hosts. Specifically, KGVHI first built a HMN by integrating human proteins, viruses and pathogenic bacteria with their biological attributes. Then KGVHI adopted a knowledge graph embedding strategy to capture the global topological structure information of the whole network. A natural language processing algorithm is used to extract the local biological attribute information from the nodes in HMN. Finally, we combined the local and global information and fed it into a blended deep neural network (DNN) for training and prediction. Compared to state-of-the-art methods, the comprehensive experimental results show that our model can obtain excellent results on the corresponding three MHI datasets. Furthermore, we also conducted two pathogenic bacteria case studies to further indicate that KGVHI has excellent predictive capabilities for potential MHI pairs.


Assuntos
Aprendizado Profundo , Humanos , Reconhecimento Automatizado de Padrão , Redes Neurais de Computação , Algoritmos , Bactérias
2.
Blood ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657197

RESUMO

Thrombotic microangiopathy (TMA) is characterized by immunothrombosis and life-threatening organ failure, but the precise underlying mechanism driving its pathogenesis remains elusive. In this study, we hypothesized that gasdermin D (GSDMD), a pore-forming protein serving as the final downstream effector of pyroptosis/interleukin (IL)-1pathway, contributes to TMA and its consequences by amplifying neutrophil maturation and subsequent necrosis. Using a murine model of focal crystalline TMA, we found that Gsdmd-deficiency ameliorated immunothrombosis, acute tissue injury and failure. Gsdmd-/- mice exhibited a decrease in mature IL-1, as well as in neutrophil maturation, 2 integrin activation, and recruitment to TMA lesions, where they formed reduced neutrophil extracellular traps both in arteries and interstitial tissue. The GSDMD inhibitor disulfiram dose-dependently suppressed human neutrophil pyroptosis in response to cholesterol crystals. Experiments with GSDMD-deficient human induced pluripotent stem cell-derived neutrophils confirmed the involvement of GSDMD in neutrophil 2 integrin activation, maturation as well as pyroptosis. Both prophylactic and therapeutic administration of disulfiram protected mice from focal TMA, acute tissue injury and failure. Our data identify GSDMD as a key mediator of focal crystalline TMA and its consequences: ischemic tissue infarction and organ failure. GSDMD could potentially serve as a therapeutic target for systemic forms of TMA.

3.
Proc Natl Acad Sci U S A ; 120(34): e2305142120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37585462

RESUMO

Introducing nitrogen fixation (nif  ) genes into eukaryotic genomes and targeting Nif components to mitochondria or chloroplasts is a promising strategy for engineering nitrogen-fixing plants. A prerequisite for achieving nitrogen fixation in crops is stable and stoichiometric expression of each component in organelles. Previously, we designed a polyprotein-based nitrogenase system depending on Tobacco Etch Virus protease (TEVp) to release functional Nif components from five polyproteins. Although this system satisfies the demand for specific expression ratios of Nif components in Escherichia coli, we encountered issues with TEVp cleavage of polyproteins targeted to yeast mitochondria. To overcome this obstacle, a version of the Nif polyprotein system was constructed by replacing TEVp cleavage sites with minimal peptide sequences, identified by knowledge-based engineering, that are susceptible to cleavage by the endogenous mitochondrial-processing peptidase. This replacement not only further reduces the number of genes required, but also prevents potential precleavage of polyproteins outside the target organelle. This version of the polyprotein-based nitrogenase system achieved levels of nitrogenase activity in E. coli, comparable to those observed with the TEVp-based polyprotein nitrogenase system. When applied to yeast mitochondria, stable and balanced expression of Nif components was realized. This strategy has potential advantages, not only for transferring nitrogen fixation to eukaryotic cells, but also for the engineering of other metabolic pathways that require mitochondrial compartmentalization.


Assuntos
Escherichia coli , Fixação de Nitrogênio , Fixação de Nitrogênio/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Saccharomyces cerevisiae/metabolismo , Poliproteínas/genética , Poliproteínas/metabolismo , Nitrogenase/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Nitrogênio/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(11): e2122954119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35238654

RESUMO

SignificanceSARS-CoV-2 continues to evolve through emerging variants, more frequently observed with higher transmissibility. Despite the wide application of vaccines and antibodies, the selection pressure on the Spike protein may lead to further evolution of variants that include mutations that can evade immune response. To catch up with the virus's evolution, we introduced a deep learning approach to redesign the complementarity-determining regions (CDRs) to target multiple virus variants and obtained an antibody that broadly neutralizes SARS-CoV-2 variants.


Assuntos
Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Amplamente Neutralizantes/farmacologia , Vacinas contra COVID-19/imunologia , Regiões Determinantes de Complementaridade , Aprendizado Profundo , Epitopos/imunologia , Humanos , Imunoterapia/métodos , Testes de Neutralização/métodos , Domínios Proteicos , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
5.
J Am Chem Soc ; 146(11): 7400-7407, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456799

RESUMO

Peptidoglycan (PG), an essential exoskeletal polymer in bacteria, is a well-known antibiotic target. PG polymerization requires the action of bacterial transglycosylases (TGases), which couple the incoming glycosyl acceptor to the donor. Interfering with the TGase activity can interrupt the PG assembly. Existing TGase inhibitors like moenomycin and Lipid II analogues always occupy the TGase active sites; other strategies to interfere with proper PG elongation have not been widely exploited. Inspired by the natural 1,6-anhydro-MurNAc termini that mark the ends of PG strands in bacteria, we hypothesized that the incorporation of an anhydromuramyl-containing glycosyl acceptor by TGase into the growing PG may effectively inhibit PG elongation. To explore this possibility, we synthesized 4-O-(N-acetyl-ß-d-glucosaminyl)-1,6-anhydro-N-acetyl-ß-d-muramyl-l-Ala-γ-d-Glu-l-Lys-d-Ala-d-Ala, 1, within 15 steps, and demonstrated that this anhydromuropeptide and its analogue lacking the peptide, 1-deAA, were both utilized by bacterial TGase as noncanonical anhydro glycosyl acceptors in vitro. The incorporation of an anhydromuramyl moiety into PG strands by TGases afforded efficient termination of glycan chain extension. Moreover, the preliminary in vitro studies of 1-deAA against Staphylococcus aureus showed that 1-deAA served as a reasonable antimicrobial adjunct of vancomycin. These insights imply the potential application of such anhydromuropeptides as novel classes of PG-terminating inhibitors, pointing toward novel strategies in antibacterial agent development.


Assuntos
Antibacterianos , Peptidoglicano , Peptidoglicano/química , Antibacterianos/farmacologia , Bactérias/metabolismo , Glicosiltransferases/metabolismo
6.
Small ; : e2401770, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764303

RESUMO

Ultrathin PtSe2 ribbons can host spin-polarized edge states and distinct edge electrocatalytic activity, emerging as a promising candidate for versatile applications in various fields. However, the direct synthesis is still challenging and the growth mechanism is still unclear. Herein, the arrayed growth of ultrathin PtSe2 ribbons on bunched vicinal Au(001) facets, via a facile chemical vapor deposition (CVD) route is reported. The ultrathin PtSe2 flakes can transform from traditional irregular shapes to desired ribbon shapes by increasing the height of bunched and unidirectionally oriented Au steps (with step height hstep) is found. This crossover, occurring at hstep ≈ 3.0 nm, defines the tailored growth from step-flow to single-terrace-confined modes, as validated by density functional theory calculations of the different system energies. On the millimeter-scale single-crystal Au(001) films with aligned steps, the arrayed ultrathin PtSe2 ribbons with tunable width of ≈20-1000 nm, which are then served as prototype electrocatalysts for hydrogen evolution reaction (HER) is achieved. This work should represent a huge leap in the direct synthesis and the mechanism exploration of arrayed ultrathin transition-metal dichalcogenides (TMDCs) ribbons, which should stimulate further explorations of the edge-related physical properties and practical applications.

7.
BMC Microbiol ; 24(1): 64, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373913

RESUMO

BACKGROUND: Multi-drug-resistant organisms (MDROs) in gram-negative bacteria have caused a global epidemic, especially the bacterial resistance to carbapenem agents. Plasmid is the common vehicle for carrying antimicrobial resistance genes (ARGs), and the transmission of plasmids is also one of the important reasons for the emergence of MDROs. Different incompatibility group plasmid replicons are highly correlated with the acquisition, dissemination, and evolution of resistance genes. Based on this, the study aims to identify relevant characteristics of various plasmids and provide a theoretical foundation for clinical anti-infection treatment. METHODS: 330 gram-negative strains with different antimicrobial phenotypes from a tertiary hospital in Henan Province were included in this study to clarify the difference in incompatibility group plasmid replicons. Additionally, we combined the information from the PLSDB database to elaborate on the potential association between different plasmid replicons and ARGs. The VITEK mass spectrometer was used for species identification, and the VITEK-compact 2 automatic microbial system was used for the antimicrobial susceptibility test (AST). PCR-based replicon typing (PBRT) detected the plasmid profiles, and thirty-three different plasmid replicons were determined. All the carbapenem-resistant organisms (CROs) were tested for the carbapenemase genes. RESULTS: 21 plasmid replicon types were detected in this experiment, with the highest prevalence of IncFII, IncFIB, IncR, and IncFIA. Notably, the detection rate of IncX3 plasmids in CROs is higher, which is different in strains with other antimicrobial phenotypes. The number of plasmid replicons they carried increased with the strain resistance increase. Enterobacterales took a higher number of plasmid replicons than other gram-negative bacteria. The same strain tends to have more than one plasmid replicon type. IncF-type plasmids tend to be associated with MDROs. Combined with PLSDB database analysis, IncFII and IncX3 are critical platforms for taking blaKPC-2 and blaNDM. CONCLUSIONS: MDROs tend to carry more complex plasmid replicons compared with non-MDROs. The plasmid replicons that are predominantly prevalent and associated with ARGs differ in various species. The wide distribution of IncF-type plasmids and their close association with MDROs should deserve our attention. Further investigation into the critical role of plasmids in the carriage, evolution, and transmission of ARGs is needed.


Assuntos
Antibacterianos , Anti-Infecciosos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Plasmídeos/genética , beta-Lactamases/genética , Bactérias Gram-Negativas/genética , Carbapenêmicos/farmacologia , Fenótipo , Replicon , Testes de Sensibilidade Microbiana , Klebsiella pneumoniae/genética
8.
Blood ; 139(23): 3402-3417, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35303071

RESUMO

Neutrophils are key players during host defense and sterile inflammation. Neutrophil dysfunction is a characteristic feature of the acquired immunodeficiency during kidney disease. We speculated that the impaired renal clearance of the intrinsic purine metabolite soluble uric acid (sUA) may account for neutrophil dysfunction. Indeed, hyperuricemia (HU, serum UA of 9-12 mg/dL) related or unrelated to kidney dysfunction significantly diminished neutrophil adhesion and extravasation in mice with crystal- and coronavirus-related sterile inflammation using intravital microscopy and an air pouch model. This impaired neutrophil recruitment was partially reversible by depleting UA with rasburicase. We validated these findings in vitro using either neutrophils or serum from patients with kidney dysfunction-related HU with or without UA depletion, which partially normalized the defective migration of neutrophils. Mechanistically, sUA impaired ß2 integrin activity and internalization/recycling by regulating intracellular pH and cytoskeletal dynamics, physiological processes that are known to alter the migratory and phagocytic capability of neutrophils. This effect was fully reversible by blocking intracellular uptake of sUA via urate transporters. In contrast, sUA had no effect on neutrophil extracellular trap formation in neutrophils from healthy subjects or patients with kidney dysfunction. Our results identify an unexpected immunoregulatory role of the intrinsic purine metabolite sUA, which contrasts the well-known immunostimulatory effects of crystalline UA. Specifically targeting UA may help to overcome certain forms of immunodeficiency, for example in kidney dysfunction, but may enhance sterile forms of inflammation.


Assuntos
Antígenos CD18 , Ácido Úrico , Animais , Antígenos CD18/metabolismo , Humanos , Imunidade Inata , Inflamação , Camundongos , Infiltração de Neutrófilos , Neutrófilos , Ácido Úrico/farmacologia , Ácido Úrico/urina
9.
Genome ; 67(6): 178-188, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38394647

RESUMO

For peanut, the lack of stable cytological markers is a barrier to tracking specific chromosomes, elucidating the genetic relationships between genomes and identifying chromosomal variations. Chromosome mapping using single-copy oligonucleotide (oligo) probe libraries has unique advantages for identifying homologous chromosomes and chromosomal rearrangements. In this study, we developed two whole-chromosome single-copy oligo probe libraries, LS-7A and LS-8A, based on the reference genome sequences of chromosomes 7A and 8A of Arachis duranensis. Fluorescence in situ hybridization (FISH) analysis confirmed that the libraries could specifically paint chromosomes 7 and 8. In addition, sequential FISH and electronic localization of LS-7A and LS-8A in A. duranensis (AA) and A. ipaensis (BB) showed that chromosomes 7A and 8A contained translocations and inversions relative to chromosomes 7B and 8B. Analysis of the chromosomes of wild Arachis species using LS-8A confirmed that this library could accurately and effectively identify A genome species. Finally, LS-7A and LS-8A were used to paint the chromosomes of interspecific hybrids and their progenies, which verified the authenticity of the interspecific hybrids and identified a disomic addition line. This study provides a model for developing specific oligo probes to identify the structural variations of other chromosomes in Arachis and demonstrates the practical utility of LS-7A and LS-8A.


Assuntos
Arachis , Coloração Cromossômica , Cromossomos de Plantas , Hibridização in Situ Fluorescente , Coloração Cromossômica/métodos , Cromossomos de Plantas/genética , Arachis/genética , Mapeamento Cromossômico , Oligonucleotídeos/genética , Translocação Genética
10.
Microb Cell Fact ; 23(1): 94, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539197

RESUMO

BACKGROUND: Surfactin, a green lipopeptide bio-surfactant, exhibits excellent surface, hemolytic, antibacterial, and emulsifying activities. However, a lack of clear understanding of the synthesis regulation mechanism of surfactin homologue components has hindered the customized production of surfactin products with different biological activities. RESULTS: In this study, exogenous valine and 2-methylbutyric acid supplementation significantly facilitated the production of C14-C15 surfactin proportions (up to 75% or more), with a positive correlation between the homologue proportion and fortified concentration. Subsequently, the branched-chain amino acid degradation pathway and the glutamate synthesis pathway are identified as critical pathways in regulating C14-C15 surfactin synthesis by transcriptome analysis. Overexpression of genes bkdAB and glnA resulted in a 1.4-fold and 1.3-fold increase in C14 surfactin, respectively. Finally, the C14-rich surfactin was observed to significantly enhance emulsification activity, achieving an EI24 exceeding 60% against hexadecane, while simultaneously reducing hemolytic activity. Conversely, the C15-rich surfactin demonstrated an increase in both hemolytic and antibacterial activities. CONCLUSION: This study presents the first evidence of a potential connection between surfactin homologue synthesis and the conversion of glutamate and glutamine, providing a theoretical basis for targeting the synthesis regulation and structure-activity relationships of surfactin and other lipopeptide compounds.


Assuntos
Ácidos Graxos , Tensoativos , Ácidos Graxos/metabolismo , Tensoativos/metabolismo , Ácido Glutâmico/metabolismo , Lipopeptídeos , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Peptídeos Cíclicos/química , Bacillus subtilis/genética
11.
Environ Res ; 242: 117739, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38007076

RESUMO

In wastewater treatment plants (WWTPs), ammonia oxidation is primarily carried out by three types of ammonia oxidation microorganisms (AOMs): ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), and comammox (CMX). Antibiotic resistance genes (ARGs), which pose an important public health concern, have been identified at every stage of wastewater treatment. However, few studies have focused on the impact of ARGs on ammonia removal performance. Therefore, our study sought to investigate the effect of the representative multidrug-resistant plasmid RP4 on the functional microorganisms involved in ammonia oxidation. Using an inhibitor-based method, we first evaluated the contributions of AOA, AOB, and CMX to ammonia oxidation in activated sludge, which were determined to be 13.7%, 41.1%, and 39.1%, respectively. The inhibitory effects of C2H2, C8H14, and 3,4-dimethylpyrazole phosphate (DMPP) were then validated by qPCR. After adding donor strains to the sludge, fluorescence in situ hybridization (FISH) imaging analysis demonstrated the co-localization of RP4 plasmids and all three AOMs, thus confirming the horizontal gene transfer (HGT) of the RP4 plasmid among these microorganisms. Significant inhibitory effects of the RP4 plasmid on the ammonia nitrogen consumption of AOA, AOB, and CMX were also observed, with inhibition rates of 39.7%, 36.2%, and 49.7%, respectively. Moreover, amoA expression in AOB and CMX was variably inhibited by the RP4 plasmid, whereas AOA amoA expression was not inhibited. These results demonstrate the adverse environmental effects of the RP4 plasmid and provide indirect evidence supporting plasmid-mediated conjugation transfer from bacteria to archaea.


Assuntos
Archaea , Betaproteobacteria , Archaea/genética , Archaea/metabolismo , Esgotos/microbiologia , Amônia , Nitrogênio/metabolismo , Desnitrificação , Hibridização in Situ Fluorescente , Oxirredução , Bactérias/genética , Bactérias/metabolismo , Plasmídeos/genética , Betaproteobacteria/genética , Betaproteobacteria/metabolismo , Antibacterianos , Filogenia , Microbiologia do Solo
12.
PLoS Genet ; 17(8): e1009724, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34398892

RESUMO

Feeding is essential for animal survival and reproduction and is regulated by both internal states and external stimuli. However, little is known about how internal states influence the perception of external sensory cues that regulate feeding behavior. Here, we investigated the neuronal and molecular mechanisms behind nutritional state-mediated regulation of gustatory perception in control of feeding behavior in the brown planthopper and Drosophila. We found that feeding increases the expression of the cholecystokinin-like peptide, sulfakinin (SK), and the activity of a set of SK-expressing neurons. Starvation elevates the transcription of the sugar receptor Gr64f and SK negatively regulates the expression of Gr64f in both insects. Interestingly, we found that one of the two known SK receptors, CCKLR-17D3, is expressed by some of Gr64f-expressing neurons in the proboscis and proleg tarsi. Thus, we have identified SK as a neuropeptide signal in a neuronal circuitry that responds to food intake, and regulates feeding behavior by diminishing gustatory receptor gene expression and activity of sweet sensing GRNs. Our findings demonstrate one nutritional state-dependent pathway that modulates sweet perception and thereby feeding behavior, but our experiments cannot exclude further parallel pathways. Importantly, we show that the underlying mechanisms are conserved in the two distantly related insect species.


Assuntos
Comportamento Alimentar/fisiologia , Percepção Gustatória/genética , Animais , Encéfalo/metabolismo , Metabolismo dos Carboidratos/fisiologia , Carboidratos/fisiologia , Colecistocinina/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Comportamento Alimentar/psicologia , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Hemípteros/genética , Hemípteros/fisiologia , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Receptores de Superfície Celular/genética , Inanição/metabolismo , Açúcares/metabolismo , Paladar/fisiologia , Percepção Gustatória/fisiologia
13.
Ecotoxicol Environ Saf ; 276: 116288, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581909

RESUMO

Cylindrospermopsin (CYN), a cyanobacterial toxin, has been detected in the global water environment. However, information concerning the potential environmental risk of CYN is limited, since the majority of previous studies have mainly focused on the adverse health effects of CYN through contaminated drinking water. The present study reported that CYN at environmentally relevant levels (0.1-100 µg/L) can significantly enhance the conjugative transfer of RP4 plasmid in Escherichia coli genera, wherein application of 10 µg/L of CYN led to maximum fold change of ∼6.5- fold at 16 h of exposure. Meanwhile, evaluation of underlying mechanisms revealed that environmental concentration of CYN exposure could increase oxidative stress in the bacterial cells, resulting in ROS overproduction. In turn, this led to an upregulation of antioxidant enzyme-related genes to avoid ROS attack. Further, inhibition of the synthesis of glutathione (GSH) was also detected, which led to the rapid depletion of GSH in cells and thus triggered the SOS response and promoted the conjugative transfer process. Increase in cell membrane permeability, upregulation of expression of genes related to pilus generation, ATP synthesis, and RP4 gene expression were also observed. These results highlight the potential impact on the spread of antimicrobial resistance in water environments.


Assuntos
Alcaloides , Toxinas Bacterianas , Toxinas de Cianobactérias , Escherichia coli , Glutationa , Plasmídeos , Uracila , Plasmídeos/genética , Glutationa/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Toxinas Bacterianas/toxicidade , Uracila/análogos & derivados , Uracila/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Conjugação Genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética
14.
J Am Soc Nephrol ; 34(3): 394-411, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36857499

RESUMO

SIGNIFICANCE STATEMENT: Cells undergoing necrosis release extracellular high mobility group box (HMGB)-1, which triggers sterile inflammation upon AKI in mice. Neither deletion of HMGB1 from tubular epithelial cells, nor HMGB1 antagonism with small molecules, affects initial ischemic tubular necrosis and immediate GFR loss upon unilateral ischemia/reperfusion injury (IRI). On the contrary, tubular cell-specific HMGB1 deficiency, and even late-onset pharmacological HMGB1 inhibition, increased functional and structural recovery from AKI, indicating that intracellular HMGB1 partially counters the effects of extracellular HMGB1. In vitro studies indicate that intracellular HMGB1 decreases resilience of tubular cells from prolonged ischemic stress, as in unilateral IRI. Intracellular HMGB1 is a potential target to enhance kidney regeneration and to improve long-term prognosis in AKI. BACKGROUND: Late diagnosis is a hurdle for treatment of AKI, but targeting AKI-CKD transition may improve outcomes. High mobility group box-1 (HMGB1) is a nuclear regulator of transcription and a driver of necroinflammation in AKI. We hypothesized that HMGB1 would also modulate AKI-CKD transition in other ways. METHODS: We conducted single-cell transcriptome analysis of human and mouse AKI and mouse in vivo and in vitro studies with tubular cell-specific depletion of Hmgb1 and HMGB1 antagonists. RESULTS: HMGB1 was ubiquitously expressed in kidney cells. Preemptive HMGB1 antagonism with glycyrrhizic acid (Gly) and ethyl pyruvate (EP) did not affect postischemic AKI but attenuated AKI-CKD transition in a model of persistent kidney hypoxia. Consistently, tubular Hmgb1 depletion in Pax8 rtTA, TetO Cre, Hmgb1fl/fl mice did not protect from AKI, but from AKI-CKD transition. In vitro studies confirmed that absence of HMGB1 or HMGB1 inhibition with Gly and EP does not affect ischemic necrosis of growth-arrested differentiated tubular cells but increased the resilience of cycling tubular cells that survived the acute injury to oxidative stress. This effect persisted when neutralizing extracellular HMGB1 with 2G7. Consistently, late-onset HMGB1 blockade with EP started after the peak of ischemic AKI in mice prevented AKI-CKD transition, even when 2G7 blocked extracellular HMGB1. CONCLUSION: Treatment of AKI could become feasible when ( 1 ) focusing on long-term outcomes of AKI; ( 2 ) targeting AKI-CKD transition with drugs initiated after the AKI peak; and ( 3 ) targeting with drugs that block HMGB1 in intracellular and extracellular compartments.


Assuntos
Injúria Renal Aguda , Proteína HMGB1 , Insuficiência Renal Crônica , Humanos , Animais , Camundongos , Rim , Regeneração , Células Epiteliais , Estresse Oxidativo , Ácido Glicirrízico
15.
J Am Soc Nephrol ; 34(9): 1513-1520, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37428955

RESUMO

SIGNIFICANCE STATEMENT: We hypothesized that triple therapy with inhibitors of the renin-angiotensin system (RAS), sodium-glucose transporter (SGLT)-2, and the mineralocorticoid receptor (MR) would be superior to dual RAS/SGLT2 blockade in attenuating CKD progression in Col4a3 -deficient mice, a model of Alport syndrome. Late-onset ramipril monotherapy or dual ramipril/empagliflozin therapy attenuated CKD and prolonged overall survival by 2 weeks. Adding the nonsteroidal MR antagonist finerenone extended survival by 4 weeks. Pathomics and RNA sequencing revealed significant protective effects on the tubulointerstitium when adding finerenone to RAS/SGLT2 inhibition. Thus, triple RAS/SGLT2/MR blockade has synergistic effects and might attenuate CKD progression in patients with Alport syndrome and possibly other progressive chronic kidney disorders. BACKGROUND: Dual inhibition of the renin-angiotensin system (RAS) plus sodium-glucose transporter (SGLT)-2 or the mineralocorticoid receptor (MR) demonstrated additive renoprotective effects in large clinical trials. We hypothesized that triple therapy with RAS/SGLT2/MR inhibitors would be superior to dual RAS/SGLT2 blockade in attenuating CKD progression. METHODS: We performed a preclinical randomized controlled trial (PCTE0000266) in Col4a3 -deficient mice with established Alport nephropathy. Treatment was initiated late (age 6 weeks) in mice with elevated serum creatinine and albuminuria and with glomerulosclerosis, interstitial fibrosis, and tubular atrophy. We block-randomized 40 male and 40 female mice to either nil (vehicle) or late-onset food admixes of ramipril monotherapy (10 mg/kg), ramipril plus empagliflozin (30 mg/kg), or ramipril plus empagliflozin plus finerenone (10 mg/kg). Primary end point was mean survival. RESULTS: Mean survival was 63.7±10.0 days (vehicle), 77.3±5.3 days (ramipril), 80.3±11.0 days (dual), and 103.1±20.3 days (triple). Sex did not affect outcome. Histopathology, pathomics, and RNA sequencing revealed that finerenone mainly suppressed the residual interstitial inflammation and fibrosis despite dual RAS/SGLT2 inhibition. CONCLUSION: Experiments in mice suggest that triple RAS/SGLT2/MR blockade may substantially improve renal outcomes in Alport syndrome and possibly other progressive CKDs because of synergistic effects on the glomerular and tubulointerstitial compartments.


Assuntos
Diabetes Mellitus Tipo 2 , Nefrite Hereditária , Insuficiência Renal Crônica , Animais , Feminino , Masculino , Camundongos , Anti-Hipertensivos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fibrose , Proteínas Facilitadoras de Transporte de Glucose/farmacologia , Proteínas Facilitadoras de Transporte de Glucose/uso terapêutico , Nefrite Hereditária/tratamento farmacológico , Nefrite Hereditária/genética , Nefrite Hereditária/patologia , Ramipril/uso terapêutico , Receptores de Mineralocorticoides , Insuficiência Renal Crônica/tratamento farmacológico , Sistema Renina-Angiotensina , Sódio , Transportador 2 de Glucose-Sódio/farmacologia , Transportador 2 de Glucose-Sódio/uso terapêutico
16.
Nano Lett ; 23(11): 5342-5349, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37219946

RESUMO

Raman spectroscopy is a powerful technique to probe structural and doping behaviors of two-dimensional (2D) materials. In MoS2, the always coexisting in-plane (E2g1) and out-of-plane (A1g) vibrational modes are used as reliable fingerprints to distinguish the number of layers, strains, and doping levels. In this work, however, we report an abnormal Raman behavior, i.e., the absence of the A1g mode in cetyltrimethylammonium bromide (CTAB)-intercalated MoS2 superlattice. This unusual behavior is quite different from the softening of the A1g mode induced by surface engineering or electric-field gating. Interestingly, under a strong laser illumination, heating, or mechanical indentation, an A1g peak gradually appears, accompanied by the migration of intercalated CTA+ cations. The abnormal Raman behavior is mainly attributed to the constraint of the out-of-plane vibration due to intercalations and resulting severe electron doping. Our work renews the understanding of Raman spectra of 2D semiconducting materials and sheds light on developing next-generation devices with tunable structures.

17.
Int J Mol Sci ; 25(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38339199

RESUMO

Multiple cis-acting elements are present in promoter sequences that play critical regulatory roles in gene transcription and expression. In this study, we isolated the cotton FDH (Fiddlehead) gene promoter (pGhFDH) using a real-time reverse transcription-PCR (qRT-PCR) expression analysis and performed a cis-acting elements prediction analysis. The plant expression vector pGhFDH::GUS was constructed using the Gateway approach and was used for the genetic transformation of Arabidopsis and upland cotton plants to obtain transgenic lines. Histochemical staining and a ß-glucuronidase (GUS) activity assay showed that the GUS protein was detected in the roots, stems, leaves, inflorescences, and pods of transgenic Arabidopsis thaliana lines. Notably, high GUS activity was observed in different tissues. In the transgenic lines, high GUS activity was detected in different tissues such as leaves, stalks, buds, petals, androecium, endosperm, and fibers, where the pGhFDH-driven GUS expression levels were 3-10-fold higher compared to those under the CaMV 35S promoter at 10-30 days post-anthesis (DPA) during fiber development. The results indicate that pGhFDH can be used as an endogenous constitutive promoter to drive the expression of target genes in various cotton tissues to facilitate functional genomic studies and accelerate cotton molecular breeding.


Assuntos
Arabidopsis , Gossypium , Gossypium/genética , Gossypium/metabolismo , Regiões Promotoras Genéticas , Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Glucuronidase/genética , Glucuronidase/metabolismo
18.
Int Wound J ; 21(2): e14733, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38339798

RESUMO

Keloids, pathological scars resulting from skin trauma, have traditionally posed significant clinical management challenges due to their persistence and high recurrence rates. Our research elucidates the pivotal roles of lipids and their derivatives in keloid development, driven by underlying mechanisms of abnormal cell proliferation, apoptosis, and extracellular matrix deposition. Key findings suggest that abnormalities in arachidonic acid (AA) synthesis and non-essential fatty acid synthesis are integral to keloid formation. Further, a complex interplay exists between lipid derivatives, notably butyric acid (BA), prostaglandin E2 (PGE2), prostaglandin D2 (PGD2), and the regulation of hyperfibrosis. Additionally, combinations of docosahexaenoic acid (DHA) with BA and 15-deoxy-Δ12,14-Prostaglandin J2 have exhibited pronounced cytotoxic effects. Among sphingolipids, ceramide (Cer) displayed limited pro-apoptotic effects in keloid fibroblasts (KFBs), whereas sphingosine 1-phosphate (S1P) was found to promote keloid hyperfibrosis, with its analogue, FTY720, demonstrating contrasting benefits. Both Vitamin D and hexadecylphosphorylcholine (HePC) showed potential antifibrotic and antiproliferative properties, suggesting their utility in keloid management. While keloids remain a prevalent concern in clinical practice, this study underscores the promising potential of targeting specific lipid molecules for the advancement of keloid therapeutic strategies.


Assuntos
Queloide , Humanos , Queloide/tratamento farmacológico , Queloide/patologia , Matriz Extracelular , Fibrose , Apoptose , Lipídeos/farmacologia , Lipídeos/uso terapêutico , Fibroblastos
19.
Biochem Biophys Res Commun ; 669: 61-67, 2023 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-37267861

RESUMO

As a member of the gasdermin family, gasdermin E (GSDME) is specifically cleaved by caspase-3, resulting in pyroptosis. To date, the biological characteristics and functions of human and mouse GSDME have been extensively studied; however, little is known of porcine GSDME (pGSDME). In this study, the full-length pGSDME-FL was cloned, which encodes 495 amino acids (aa) that have closely evolutionary relationships to the homolog of camelus, aquatic mammals, cattle and goat. Moreover, pGSDME was detected at different levels of expression in 21 tissues and 5 pig-derived cell lines tested by qRT-PCR, with the highest expression levels in mesenteric lymph nodes and PK-15 cell lines. Anti-pGSDME polyclonal antibody (pAb) with good specificity was generated by expressing the truncated recombinant protein pGSDME-1-208 and immunizing the rabbits. By western blot analysis using highly specific anti-pGSDME polyclonal antibody (pAb) prepared as primary antibody, it was not only confirmed that paclitaxel and cisplatin were positive stimuli to pGSDME cleavage and caspase-3 activation, but also identified the aspartate (D268) at position 268th of pGSDME as a cleavage site of caspase-3, and the overexpressed pGSDME-1-268 possesses cytotoxicity to HEK-293T cells, indicating that pGSDME-1-268 may contain active domains and involve pGSDME-mediated pyroptosis. These results lay a foundation for further investigating the function of pGSDME, especially its role in pyroptosis and its interaction with pathogens.


Assuntos
Gasderminas , Piroptose , Bovinos , Humanos , Animais , Camundongos , Suínos , Coelhos , Caspase 3/genética , Caspase 3/metabolismo , Piroptose/fisiologia , Cisplatino , Clonagem Molecular , Mamíferos/metabolismo
20.
Small ; 19(23): e2300766, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36866500

RESUMO

Scaling up the chemical vapor deposition (CVD) of monolayer transition metal dichalcogenides (TMDCs) is in high demand for practical applications. However, for CVD-grown TMDCs on a large scale, there are many existing factors that result in their poor uniformity. In particular, gas flow, which usually leads to inhomogeneous distributions of precursor concentrations, has yet to be well controlled. In this work, the growth of uniform monolayer MoS2 on a large scale by the delicate control of gas flows of precursors, which is realized by vertically aligning a well-designed perforated carbon nanotube (p-CNT) film face-to-face with the substrate in a horizontal tube furnace, is achieved. The p-CNT film releases gaseous Mo precursor from the solid part and allows S vapor to pass through the hollow part, resulting in uniform distributions of both gas flow rate and precursor concentrations near the substrate. Simulation results further verify that the well-designed p-CNT film guarantees a steady gas flow and a uniform spatial distribution of precursors. Consequently, the as-grown monolayer MoS2 shows quite good uniformity in geometry, density, structure, and electrical properties. This work provides a universal pathway for the synthesis of large-scale uniform monolayer TMDCs, and will advance their applications in high-performance electronic devices.

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