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Clostridium perfringens (C. perfringens), a Gram-positive bacterium, produces a variety of toxins and extracellular enzymes that can lead to disease in both humans and animals. Common symptoms include abdominal swelling, diarrhea, and intestinal inflammation. Severe cases can result in complications like intestinal hemorrhage, edema, and even death. The primary toxins contributing to morbidity in C. perfringens-infected intestines are CPA, CPB, CPB2, CPE, and PFO. Amongst these, CPB, CPB2, and CPE are implicated in apoptosis development, while CPA is associated with cell death, increased intracellular ROS levels, and the release of the inflammatory factor IL-18. However, the exact mechanism by which PFO toxins exert their effects in the infected gut is still unidentified. This study demonstrates that a C. perfringens PFO toxin infection disrupts the intestinal epithelial barrier function through in vitro and in vivo models. This study emphasizes the notable influence of PFO toxins on intestinal barrier integrity in the context of C. perfringens infections. It reveals that PFO toxins increase ROS production by causing mitochondrial damage, triggering pyroptosis in IPEC-J2 cells, and consequently resulting in compromised intestinal barrier function. These results offer a scientific foundation for developing preventive and therapeutic approaches against C. perfringens infections.
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Toxinas Bacterianas , Clostridium perfringens , Células Epiteliais , Proteínas Hemolisinas , Mucosa Intestinal , Piroptose , Espécies Reativas de Oxigênio , Clostridium perfringens/patogenicidade , Toxinas Bacterianas/toxicidade , Toxinas Bacterianas/metabolismo , Piroptose/efeitos dos fármacos , Animais , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/toxicidade , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Camundongos , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacosRESUMO
The blood-brain barrier (BBB) is a complex structure that separates the central nervous system (CNS) from the peripheral blood circulation. Effective communication between different cell types within the BBB is crucial for its proper functioning and maintenance of homeostasis. In this study, we demonstrate that meningitic Escherichia coli (E. coli)-induced WNT5B plays a role in facilitating intercellular communication between astrocytes and brain microvascular endothelial cells (BMECs). We discovered that astrocytes-derived WNT5B activates the non-canonical WNT signaling pathway JNK/c-JUN in BMECs through its receptor ROR1, leading to inhibition of ZO-1 expression and impairment of the tight junction integrity in BMECs. Notably, our findings reveal that c-JUN, a transcription factor, directly regulates ZO-1 expression. By employing a dual luciferase reporting system and chromatin immunoprecipitation techniques, we identified specific binding sites of c-JUN on the ZO-1 promoter region. Overall, our study highlights the involvement of WNT5B in mediating intercellular communication between astrocytes and BMECs, provides insights into the role of WNT5B in meningitic E. coli-induced disruption of BBB integrity, and suggests potential therapeutic targeting of WNT5B as a strategy to address BBB dysfunction.
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Escherichia coli (E. coli) is an important foodborne pathogen and a biomarker for monitoring antimicrobial resistance. Investigating the prevalence of E. coli in the poultry industry holds great importance, particularly in Henan province, a major poultry-producing region in China. Here, we investigated the antimicrobial resistance (AMR) phenotypes of E. coli strains obtained from the poultry industry in Henan, China. A total of 344 E. coli strains were isolated from 638 samples collected from seven farms, three slaughterhouses, and ten terminal markets. Approximately 96.4%, 81.7%, and 52.5% of the isolates from the farms, slaughterhouses, and terminal markets exhibited multidrug resistance. Whole-genome sequencing was performed on 169 strains to reveal their genomic characteristics. The sequence type (ST) analysis revealed that ST10 and ST156 were the most frequent types within the poultry supply chain, whereas ST10 and ST162 were commonly found across the farms, slaughterhouses, and terminal markets. Fourteen ST10 E. coli strains belonged to phylogenetic group A, while fifteen ST165 and six ST162 E. coli strains belonged to phylogenetic group B1. In addition, several antimicrobial resistance genes and virulence factor genes were identified. The blaNDM-5 gene mediated carbapenem resistance in two E. coli strains, while mcr-1-mediated colistin resistance was detected in nine E. coli strains. Phylogenetic group A exhibited fewer virulence genes compared to other groups of E. coli. Plasmid replicons, such as IncFIB (AP001918), IncX1, IncFIC (FII), and IncFII (pHN7A8), were frequently observed. These findings provide valuable insights into the current AMR profiles of E. coli strains isolated from the poultry industry in Central China and highlight the need to implement good manufacturing practices and reduce antibiotic usage to mitigate potential risks associated with E. coli.
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Streptococcus pneumoniae (S. pneumoniae) represents a major human bacterial pathogen leading to high morbidity and mortality in children and the elderly. Recent research emphasizes the role of extracellular vesicles (EVs) in bacterial pathogenicity. However, the contribution of S. pneumoniae EVs (pEVs) to host-microbe interactions has remained unclear. Here, we observed that S. pneumoniae infections in mice led to severe lung injuries and alveolar epithelial barrier (AEB) dysfunction. Infections of S. pneumoniae reduced the protein expression of tight junction protein OCLN (occludin) and activated macroautophagy/autophagy in lung tissues of mice and A549 cells. Mechanically, S. pneumoniae induced autophagosomal degradation of OCLN leading to AEB impairment in the A549 monolayer. S. pneumoniae released the pEVs that could be internalized by alveolar epithelial cells. Through proteomics, we profiled the cargo proteins inside pEVs and found that these pEVs contained many virulence factors, among which we identified a eukaryotic-like serine-threonine kinase protein StkP. The internalized StkP could induce the phosphorylation of BECN1 (beclin 1) at Ser93 and Ser96 sites, initiating autophagy and resulting in autophagy-dependent OCLN degradation and AEB dysfunction. Finally, the deletion of stkP in S. pneumoniae completely protected infected mice from death, significantly alleviated OCLN degradation in vivo, and largely abolished the AEB disruption caused by pEVs in vitro. Overall, our results suggested that pEVs played a crucial role in the spread of S. pneumoniae virulence factors. The cargo protein StkP in pEVs could communicate with host target proteins and even hijack the BECN1 autophagy initiation pathway, contributing to AEB disruption and bacterial pathogenicity.Abbreviations: AEB: alveolarepithelial barrier; AECs: alveolar epithelial cells; ATG16L1: autophagy related 16 like 1; ATP:adenosine 5'-triphosphate; BafA1: bafilomycin A1; BBB: blood-brain barrier; CFU: colony-forming unit; co-IP: co-immunoprecipitation; CQ:chloroquine; CTRL: control; DiO: 3,3'-dioctadecylox-acarbocyanineperchlorate; DOX: doxycycline; DTT: dithiothreitol; ECIS: electricalcell-substrate impedance sensing; eGFP: enhanced green fluorescentprotein; ermR: erythromycin-resistance expression cassette; Ery: erythromycin; eSTKs: eukaryotic-like serine-threoninekinases; EVs: extracellular vesicles; HA: hemagglutinin; H&E: hematoxylin and eosin; HsLC3B: human LC3B; hpi: hours post-infection; IP: immunoprecipitation; KD: knockdown; KO: knockout; LAMP1: lysosomal associated membrane protein 1; LC/MS: liquid chromatography-mass spectrometry; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MVs: membranevesicles; NC:negative control; NETs:neutrophil extracellular traps; OD: optical density; OMVs: outer membrane vesicles; PBS: phosphate-buffered saline; pEVs: S.pneumoniaeextracellular vesicles; protK: proteinase K; Rapa: rapamycin; RNAi: RNA interference; S.aureus: Staphylococcusaureus; SNF:supernatant fluid; sgRNA: single guide RNA; S.pneumoniae: Streptococcuspneumoniae; S.suis: Streptococcussuis; TEER: trans-epithelium electrical resistance; moi: multiplicity ofinfection; TEM:transmission electron microscope; TJproteins: tight junction proteins; TJP1/ZO-1: tight junction protein1; TSA: tryptic soy agar; WB: western blot; WT: wild-type.
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Células Epiteliais Alveolares , Autofagia , Vesículas Extracelulares , Streptococcus pneumoniae , Animais , Vesículas Extracelulares/metabolismo , Autofagia/fisiologia , Streptococcus pneumoniae/patogenicidade , Streptococcus pneumoniae/metabolismo , Humanos , Células A549 , Camundongos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/microbiologia , Camundongos Endogâmicos C57BL , Proteína Beclina-1/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , FosforilaçãoRESUMO
Zoonoses are diseases and infections naturally transmitted between humans and vertebrate animals. They form the dominant group of diseases among emerging infectious diseases and represent critical threats to global health security. This dilemma is largely attributed to our insufficient knowledge of the pathogenesis regarding zoonotic spillover. Long non-coding RNAs (lncRNAs) are transcripts with limited coding capacity. Recent technological advancements have enabled the identification of numerous lncRNAs in humans, animals, and even pathogens. An increasing body of literature suggests that lncRNAs function as key regulators in zoonotic infection. They regulate immune-related epigenetic, transcriptional, and post-transcriptional events across a broad range of organisms. In this review, we discuss the recent research progress on the roles of lncRNAs in zoonoses. We address the classification and regulatory mechanisms of lncRNAs in the interaction between host and zoonotic pathogens. Additionally, we explore the surprising function of pathogen-derived lncRNAs in mediating the pathogenicity and life cycle of zoonotic bacteria, viruses, and parasites. Understanding how these lncRNAs influence the zoonotic pathogenesis will provide important therapeutic insights to the prevention and control of zoonoses.
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Doenças Transmissíveis Emergentes , RNA Longo não Codificante , Vírus , Animais , Humanos , RNA Longo não Codificante/genética , Zoonoses/genéticaRESUMO
Enterotoxigenic Escherichia coli (ETEC) causes severe diarrhea in piglets. The current primary approach for ETEC prevention and control relies on antibiotics, as few effective vaccines are available. Consequently, an urgent clinical demand exists for developing an effective vaccine to combat this disease. Here, we utilized food-grade Lactococcus lactis NZ3900 and expression plasmid pNZ8149 as live vectors, together with the secreted expression peptide Usp45 and the cell wall non-covalent linking motif LysM, to effectively present the mutant LTA subunit, the LTB subunit of heat-labile enterotoxin, and the FaeG of F4 pilus on the surface of recombinant lactic acid bacteria (LAB). Combining three recombinant LAB as a live vector oral vaccine, we assessed its efficacy in preventing F4+ ETEC infection. The results demonstrate that oral immunization conferred effective protection against F4+ ETEC infection in mice and piglets lacking maternal antibodies during weaning. Sow immunization during late pregnancy generated significantly elevated antibodies in colostrum, which protected piglets against F4+ ETEC infection during lactation. Moreover, booster immunization on piglets during lactation significantly enhanced their resistance to F4+ ETEC infection during the weaning stage. This study highlights the efficacy of an oral LAB vaccine in preventing F4+ ETEC infection in piglets by combining the sow immunization and booster immunization of piglets, providing a promising vaccination strategy for future prevention and control of ETEC-induced diarrhea in piglets.
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With the continuous development of cloud computing, the application of cloud storage has become more and more popular. To ensure the integrity and availability of cloud data, scholars have proposed several cloud data auditing schemes. Still, most need help with outsourced data integrity, controlled outsourcing, and source file auditing. Therefore, we propose a controlled delegation outsourcing data integrity auditing scheme based on the identity-based encryption model. Our proposed scheme allows users to specify a dedicated agent to assist in uploading data to the cloud. These authorized proxies use recognizable identities for authentication and authorization, thus avoiding the need for cumbersome certificate management in a secure distributed computing system. While solving the above problems, our scheme adopts a bucket-based red-black tree structure to efficiently realize the dynamic updating of data, which can complete the updating of data and rebalancing of structural updates constantly and realize the high efficiency of data operations. We define the security model of the scheme in detail and prove the scheme's security under the difficult problem assumption. In the performance analysis section, the proposed scheme is analyzed experimentally in comparison with other schemes, and the results show that the proposed scheme is efficient and secure.
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Escherichia coli continues to be the predominant Gram-negative pathogen causing neonatal meningitis worldwide. Inflammatory mediators have been implicated in the pathogenesis of meningitis and are key therapeutic targets. The role of interleukin-22 (IL-22) in various diseases is diverse, with both protective and pathogenic effects. However, little is understood about the mechanisms underlying the damaging effects of IL-22 on the blood-brain barrier (BBB) in E. coli meningitis. We observed that meningitic E. coli infection induced IL-22 expression in the serum and brain of mice. The tight junction proteins (TJPs) components ZO-1, Occludin, and Claudin-5 were degraded in the mouse brain and human brain microvascular endothelial cells (hBMEC) following IL-22 administration. Moreover, the meningitic E. coli-caused increase in BBB permeability in wild-type mice was restored by knocking out IL-22. Mechanistically, IL-22 activated the STAT3-VEGFA signaling cascade in E. coli meningitis, thus eliciting the degradation of TJPs to induce BBB disruption. Our data indicated that IL-22 is an essential host accomplice during E. coli-caused BBB disruption and could be targeted for the therapy of bacterial meningitis.
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Infecções por Escherichia coli , Meningites Bacterianas , Meningite devida a Escherichia coli , Humanos , Camundongos , Animais , Barreira Hematoencefálica , Meningite devida a Escherichia coli/metabolismo , Meningite devida a Escherichia coli/microbiologia , Meningite devida a Escherichia coli/patologia , Escherichia coli/metabolismo , Células Endoteliais , Interleucina 22 , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/farmacologiaRESUMO
The advanced Gas Insulated Switchgear/Gas Insulated Lines (GIS/GIL) transmission equipment serves as an essential physical infrastructure for establishing a new energy power system. An analysis spanning nearly a decade on faults arising from extra/ultra-high voltage discharges reveals that over 60% of such faults are attributed to the discharge of metal particles and dust. While existing technical means, such as ultra-high frequency and ultrasonic sensing, exhibit effectiveness in online monitoring of particles larger than sub-millimeter dimensions, the inherent randomness and elusive nature of micron-nano dust pose challenges for effective characterization through current technology. This elusive micron-nano dust, likely concealed as a latent threat, necessitates special attention due to its potential as a "safety killer". To address the challenges associated with detecting micron-nano dust and comprehending its intricate mechanisms, this paper introduces a micron-nano dust adsorption experimental platform tailored for observation and practical application in GIS/GIL operations. The findings highlight that micron-nano dust's adsorption state in the electric field predominantly involves agglomerative adsorption along the insulator surface and diffusive adsorption along the direction of the ground electrode. The pivotal factors influencing dust movement include the micron-nano dust's initial position, mass, material composition, and applied voltage. Further elucidation emphasizes the potential of micron-nano dust as a concealed safety hazard. The study reveals specific physical phenomena during the adsorption process. Agglomerative adsorption results in micron-nano dust speckles forming on the epoxy resin insulator's surface. With increasing voltage, these speckles undergo an "explosion", forming an annular dust halo with deepening contours. This phenomenon, distinct from the initial adsorption, is considered a contributing factor to flashovers along the insulator's surface. The physical mechanism behind flashovers triggered by micron-nano dust is uncovered, highlighting the formation of a localized short circuit area and intense electric field distortion constituted by dust speckles. These findings establish a theoretical foundation and technical support for enhancing the safe operational performance of AC and DC transmission pipelines' insulation.
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BACKGROUND: Meningitic Escherichia coli (E. coli) is the major etiological agent of bacterial meningitis, a life-threatening infectious disease with severe neurological sequelae and high mortality. The major cause of central nervous system (CNS) damage and sequelae is the bacterial-induced inflammatory storm, where the immune response of the blood-brain barrier (BBB) is crucial. METHODS: Western blot, real-time PCR, enzyme-linked immunosorbent assay, immunofluorescence, and dual-luciferase reporter assay were used to investigate the suppressor role of transforming growth factor beta 1 (TGFß1) in the immune response of brain microvascular endothelial cells elicited by meningitic E. coli. RESULT: In this work, we showed that exogenous TGFß1 and induced noncanonical Hedgehog (HH) signaling suppressed the endothelial immune response to meningitic E. coli infection via upregulation of intracellular miR-155. Consequently, the increased miR-155 suppressed ERK1/2 activation by negatively regulating KRAS, thereby decreasing IL-6, MIP-2, and E-selectin expression. In addition, the exogenous HH signaling agonist SAG demonstrated promising protection against meningitic E. coli-induced neuroinflammation. CONCLUSION: Our work revealed the effect of TGFß1 antagonism on E. coli-induced BBB immune response and suggested that activation of HH signaling may be a potential protective strategy for future bacterial meningitis therapy. Video Abstract.
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Meningites Bacterianas , Meningite devida a Escherichia coli , MicroRNAs , Humanos , Escherichia coli/genética , Proteínas Hedgehog/metabolismo , Células Endoteliais/metabolismo , Meningite devida a Escherichia coli/metabolismo , Encéfalo/metabolismo , Barreira Hematoencefálica/microbiologia , Meningites Bacterianas/metabolismo , Imunidade , MicroRNAs/metabolismoRESUMO
Numerous studies have shown that exosomes play a regulatory role in a variety of biological processes as well as in disease development and progression. However, exosome-mediated intercellular communication between brain microvascular endothelial cells (BMECs) and astrocytes during meningitic Escherichia coli (E. coli)-induced neuroinflammation remains largely unknown. Here, by using in vivo and in vitro models, we demonstrate that exosomes derived from meningitic E. coli-infected BMECs can activate the inflammatory response of astrocytes. A label-free quantitation approach coupled with LC-MS/MS was used to compare the exosome proteomic profiles of human BMECs (hBMECs) in response to meningitic E. coli infection. A total of 57 proteins exhibited significant differences in BMEC-derived exosomes during the infection. Among these proteins, growth differentiation factor 15 (GDF15) was significantly increased in BMEC-derived exosomes during the infection, which triggered the Erk1/2 signaling pathway and promoted the activation of astrocytes. The identification and characterization of exosome protein profiles in BMECs during meningitic E. coli infection will contribute to the understanding of the underlying pathogenic mechanisms from the perspective of intercellular communication between BMECs and astrocytes, and provide new insights for future prevention and treatment of E. coli meningitis.
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Astrócitos , Encéfalo , Células Endoteliais , Escherichia coli , Exossomos , Exossomos/metabolismo , Astrócitos/metabolismo , Astrócitos/microbiologia , Astrócitos/patologia , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , Células Endoteliais/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Humanos , Animais , Microvasos/patologia , Microvasos/metabolismo , Meningite devida a Escherichia coli/metabolismo , Meningite devida a Escherichia coli/microbiologia , Meningite devida a Escherichia coli/patologiaRESUMO
Bacterial meningitis remains a leading cause of infection-related mortality worldwide. Although Escherichia coli (E. coli) is the most common etiology of neonatal meningitis, the underlying mechanisms governing bacterial blood-brain barrier (BBB) disruption during infection remain elusive. We observed that infection of human brain microvascular endothelial cells with meningitic E. coli triggers the activation of early growth response 1 (Egr-1), a host transcriptional activator. Through integrated chromatin immunoprecipitation sequencing and transcriptome analysis, we identified Egr-1 as a crucial regulator for maintaining BBB integrity. Mechanistically, Egr-1 induced cytoskeletal changes and downregulated tight junction protein expression by directly targeting VEGFA, PDGFB, and ANGPTL4, resulting in increased BBB permeability. Meanwhile, Egr-1 also served as a master regulator in the initiation of neuroinflammatory response during meningitic E. coli infection. Our findings support an Egr-1-dependent mechanism of BBB disruption by meningitic E. coli, highlighting a promising therapeutic target for bacterial meningitis.
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Meningites Bacterianas , Meningite devida a Escherichia coli , Humanos , Recém-Nascido , Barreira Hematoencefálica/microbiologia , Células Endoteliais/metabolismo , Escherichia coli , Meningites Bacterianas/metabolismo , Meningite devida a Escherichia coli/metabolismoRESUMO
Receptor-interacting protein kinase 1 (RIPK1) is a key regulator of cellular necroptosis, which is considered as an important therapeutic target for necroptosis-related indications. Herein, we report the structural optimization and structure-activity relationship investigations of a series of eutectic 5-substituted-indole-3-carboxamide derivatives. The prioritized compound 10b exhibited low nanomolar IC50 values against RIPK1 and showed good kinase selectivity. Based on its eutectic structure, 10b occupied both the allosteric and ATP binding pockets of RIPK1, making it a potent dual-mode inhibitor of RIPK1. In vitro, 10b had a potent protective effect against necroptosis in cells. Compound 10b also provided robust protection in a TNFα-induced systemic inflammatory response syndrome (SIRS) model and imiquimod (IMQ)-induced psoriasis model. It also showed good pharmacokinetic properties and low toxicity. Overall, 10b is a promising lead compound for drug discovery targeting RIPK1 and warrants further study.
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Síndrome de Resposta Inflamatória Sistêmica , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/metabolismo , Relação Estrutura-Atividade , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores , Apoptose , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/químicaRESUMO
Neuroinflammation has been implicated in the initiation and progression of several central nervous system (CNS) disorders, including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, ischemic stroke, traumatic brain injury, spinal cord injury, viral encephalitis, and bacterial encephalitis. Microglia and astrocytes are essential in neural development, maintenance of synaptic connections, and homeostasis in a healthy brain. The activation of astrocytes and microglia is a defense mechanism of the brain against damaged tissues and harmful pathogens. However, their activation triggers neuroinflammation, which can exacerbate or induce CNS injury. Non-coding RNAs (ncRNAs) are functional RNA molecules that lack coding capabilities but can actively regulate mRNA expression and function through various mechanisms. ncRNAs are highly expressed in astrocytes and microglia and are potential mediators of neuroinflammation. We reviewed the recent research progress on the role of miRNAs, lncRNAs, and circRNAs in regulating neuroinflammation in various CNS diseases. Understanding how these ncRNAs affect neuroinflammation will provide important therapeutic insights for preventing and managing CNS dysfunction.
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MicroRNAs , RNA Longo não Codificante , Humanos , Astrócitos , Microglia , Doenças Neuroinflamatórias , RNA Longo não Codificante/genéticaRESUMO
Meningitis is a major clinical manifestation of Escherichia coli (E. coli) infection characterized by inflammation of the meninges and subarachnoid space. Many chemokines are secreted during meningitic E. coli infection, of which C-X-C motif chemokine 3 (CXCL3) is the most highly expressed. However, it is unclear how CXCL3 plays a role in meningitic E. coli infection. Therefore, this study used in vitro and in vivo assays to clarify these contributions and to identify novel therapeutic targets for central nervous system inflammation. We found a significantly upregulated expression of CXCL3 in human brain microvascular endothelial cells and U251 cells after meningitic E. coli infection, and the CXCL3 receptor, C-X-C motif chemokine receptor 2 (CXCR2), was expressed in microglia. Furthermore, CXCL3 induced M1 microglia by selectively activating mitogen-activated protein kinases signaling and significantly upregulating tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6, nitric oxide synthase 2 (NOS2), and cluster of differentiation 86 (CD86) expression levels, promoting an inflammatory response. Our findings clarify the role of CXCL3 in meningitic E. coli-induced neuroinflammation and demonstrate that CXCL3 may be a potential therapeutic target for future investigation and prevention of E. coli-induced neuroinflammation.
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Infecções por Escherichia coli , Meningite , Humanos , Escherichia coli/metabolismo , Microglia/metabolismo , Doenças Neuroinflamatórias , Células Endoteliais , Quimiocinas/metabolismo , Inflamação/metabolismo , Infecções por Escherichia coli/metabolismoRESUMO
Emerging SARS-CoV-2 variants, particularly the Omicron variant and its sublineages, continually threaten the global public health. Small molecule antivirals are an effective treatment strategy to fight against the virus. However, the first-generation antivirals either show limited clinical efficacy and/or have some defects in pharmacokinetic (PK) properties. Moreover, with increased use of these drugs across the globe, they face great pressure of drug resistance. We herein present the discovery and characterization of a new generation antiviral drug candidate (SY110), which is a potent and selective inhibitor of SARS-CoV-2 main protease (Mpro). This compound displayed potent in vitro antiviral activity against not only the predominant SARS-CoV-2 Omicron sublineage BA.5, but also other highly pathogenic human coronaviruses including SARS-CoV-1 and MERS-CoV. In the Omicron-infected K18-hACE2 mouse model, oral treatment with SY110 significantly lowered the viral burdens in lung and alleviated the virus-induced pathology. Importantly, SY110 possesses favorable PK properties with high oral drug exposure and oral bioavailability, and also an outstanding safety profile. Furthermore, SY110 exhibited sensitivity to several drug-resistance Mpro mutations. Collectively, this investigation provides a promising new drug candidate against Omicron and other variants of SARS-CoV-2.
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COVID-19 , Proteases 3C de Coronavírus , SARS-CoV-2 , Animais , Humanos , Camundongos , Administração Oral , Antivirais/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , Tratamento Farmacológico da COVID-19/métodos , Proteases 3C de Coronavírus/antagonistas & inibidoresRESUMO
Despite advances in supportive care and antimicrobial treatment, bacterial meningitis remains the most serious infection of the central nervous system (CNS) that poses a serious risk to life. This clinical dilemma is largely due to our insufficient knowledge of the pathology behind this disease. By controlling the entry of molecules into the CNS microenvironment, the blood-brain barrier (BBB), a highly selective cellular monolayer that is specific to the CNS's microvasculature, regulates communication between the CNS and the rest of the body. A defining feature of the pathogenesis of bacterial meningitis is the increase in BBB permeability. So far, several contributing factors for BBB disruption have been reported, including direct cellular damage brought on by bacterial virulence factors, as well as host-specific proteins or inflammatory pathways being activated. Recent studies have demonstrated that targeting pathological factors contributing to enhanced BBB permeability is an effective therapeutic complement to antimicrobial therapy for treating bacterial meningitis. Hence, understanding how these meningitis-causing pathogens affect the BBB permeability will provide novel perspectives for investigating bacterial meningitis's pathogenesis, prevention, and therapies. Here, we summarized the recent research progress on meningitis-causing pathogens disrupting the barrier function of BBB. This review provides handy information on BBB disruption by meningitis-causing pathogens, and helps design future research as well as develop potential combination therapies.
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Barreira Hematoencefálica , Meningites Bacterianas , Humanos , Barreira Hematoencefálica/metabolismo , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/metabolismo , Sistema Nervoso Central , Transporte Biológico , BactériasRESUMO
In recent years, China's local governments have issued numerous bonds to support the country's economic development. However, as total debt accumulates, the pressure on debt repayments is gradually increasing. To increase the sustainability of local government debt, we propose a multi-period stochastic optimization-based approach to determining the portfolio composition of issued bonds, with the goal of minimizing the expected cost under the constraints of liquidity risk and cost deviation risk. Liquidity risk is measured by conditional payment-at-risk ( CPaR ), and cost deviation risk is measured by conditional value-at-risk ( CVaR ). By bounding CVaR and CPaR , local governments can control the levels of cost deviation risk and liquidity risk. To alleviate future liquidity risk, which is caused by the issuance of a large number of long-term bonds to deliberately reduce repayment pressure within a debt planning horizon, we consider an extended liquidity planning horizon to manage both current and future liquidity risk. Based on this, we analyze the efficient frontier and portfolio compositions of issued bond under the constraints of different CVaR and CPaR levels. Compared with actual Chinese local government bond portfolios, the efficient frontier performs better for different issuance strategies.
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The retrieval of hit/lead compounds with novel scaffolds during early drug development is an important but challenging task. Various generative models have been proposed to create drug-like molecules. However, the capacity of these generative models to design wet-lab-validated and target-specific molecules with novel scaffolds has hardly been verified. We herein propose a generative deep learning (GDL) model, a distribution-learning conditional recurrent neural network (cRNN), to generate tailor-made virtual compound libraries for given biological targets. The GDL model is then applied to RIPK1. Virtual screening against the generated tailor-made compound library and subsequent bioactivity evaluation lead to the discovery of a potent and selective RIPK1 inhibitor with a previously unreported scaffold, RI-962. This compound displays potent in vitro activity in protecting cells from necroptosis, and good in vivo efficacy in two inflammatory models. Collectively, the findings prove the capacity of our GDL model in generating hit/lead compounds with unreported scaffolds, highlighting a great potential of deep learning in drug discovery.
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Aprendizado Profundo , Redes Neurais de Computação , Descoberta de Drogas , Necroptose , Desenho de FármacosRESUMO
BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly contagious, and the neurological symptoms of SARS-CoV-2 infection have already been reported. However, the mechanisms underlying the effect of SARS-CoV-2 infection on patients with central nervous system injuries remain unclear. METHODS: The high-throughput RNA sequencing was applied to analyze the transcriptomic changes in SK-N-SH cells after SARS-CoV-2 infection. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to identify the functions of differentially expressed genes and related pathways. RESULTS: A total of 820 mRNAs were significantly altered, including 671 upregulated and 149 downregulated mRNAs (showing an increase of ≥ 2-fold or decrease to ≤ 0.5-fold, respectively; p ≤ 0.05). Moreover, we verified the significant induction of cytokines, chemokines, and their receptors, as well as the activation of NF-κB, p38, and Akt signaling pathways, in SK-N-SH by SARS-CoV-2. CONCLUSIONS: To our knowledge, this is the first time the transcriptional profiles of the host mRNAs involved in SARS-CoV-2 infection of SK-N-SH cells have been reported. These findings provide novel insight into the pathogenic mechanism of SARS-CoV-2 and might constitute a new approach for future prevention and treatment of SARS-CoV-2-induced central nervous system infection.