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1.
Cell Commun Signal ; 22(1): 123, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360663

RESUMEN

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.


Asunto(s)
Meningitis Bacterianas , Meningitis por Escherichia coli , MicroARNs , Humanos , Escherichia coli/genética , Proteínas Hedgehog/metabolismo , Células Endoteliales/metabolismo , Meningitis por Escherichia coli/metabolismo , Encéfalo/metabolismo , Barrera Hematoencefálica/microbiología , Meningitis Bacterianas/metabolismo , Inmunidad , MicroARNs/metabolismo
2.
ACS Infect Dis ; 10(3): 988-999, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38317607

RESUMEN

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.


Asunto(s)
Infecciones por Escherichia coli , Meningitis Bacterianas , Meningitis por Escherichia coli , Humanos , Ratones , Animales , Barrera Hematoencefálica , Meningitis por Escherichia coli/metabolismo , Meningitis por Escherichia coli/microbiología , Meningitis por Escherichia coli/patología , Escherichia coli/metabolismo , Células Endoteliales , Interleucina-22 , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/farmacología
3.
R I Med J (2013) ; 107(1): 12-14, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38166068

RESUMEN

Spontaneous community-acquired meningitis caused by E. coli is rare in the adult population. It is associated with a high risk of morbidity and mortality. We describe a case of a 72-year-old woman who presented with altered mental status and neck stiffness and was found to have E. coli meningitis. Urine cultures grew E. coli, representing a likely source. The E. coli strain was identified as sequence type 73 (E. coli ST73). Her symptoms and laboratory values improved following antibiotic initiation, and she was discharged from the hospital to a rehabilitation facility.


Asunto(s)
Infecciones por Escherichia coli , Meningitis por Escherichia coli , Meningitis , Anciano , Femenino , Humanos , Antibacterianos/uso terapéutico , Escherichia coli , Infecciones por Escherichia coli/diagnóstico , Infecciones por Escherichia coli/tratamiento farmacológico , Meningitis/diagnóstico , Meningitis/tratamiento farmacológico , Meningitis/etiología , Meningitis por Escherichia coli/diagnóstico , Meningitis por Escherichia coli/complicaciones , Meningitis por Escherichia coli/tratamiento farmacológico
4.
Cell Commun Signal ; 22(1): 44, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233877

RESUMEN

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.


Asunto(s)
Meningitis Bacterianas , Meningitis por Escherichia coli , Humanos , Recién Nacido , Barrera Hematoencefálica/microbiología , Células Endoteliales/metabolismo , Escherichia coli , Meningitis Bacterianas/metabolismo , Meningitis por Escherichia coli/metabolismo
5.
J Child Neurol ; 38(8-9): 528-536, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37574798

RESUMEN

BACKGROUND: We aimed to build a prediction nomogram for early prediction of poor prognosis in children with Escherichia coli meningitis and analyzed the course of treatment and discharge criteria. METHODS: Eighty-seven pediatric patients with E coli meningitis were retrospectively recruited from the Children's Hospital of Chongqing Medical University between June 2012 and November 2021. Univariate analysis and binary logistic analysis were used to evaluate the risk factors, and the prediction model was built. RESULTS: E coli meningitis is more common in children <3 months old in our study (86.2%). Common complications were subdural effusion (39.1%), followed by hydrocephalus (13.8%) and repeated convulsions (12.6%). The mortality rate and sequelae rate of E coli meningitis in children was ∼10.9% and ∼6.3%, respectively. Univariate analysis showed that 13 clinical indicators were associated with poor prognosis of E coli meningitis in children. In binary logistic analysis, risk factors were seizures (P = .032) and the last cerebrospinal fluid glucose content before discharge (P = .002). A graphical nomogram was designed. The area under the receiver operating characteristic curve was 0.913. The Hosmer-Lemeshow test showed that the model was a good fit (P = .648). Internal validation proved the reliability of the prediction nomogram. CONCLUSIONS: E coli meningitis is more common in children <3 months old in our study. The rate of complications and sequelae are high. The prediction nomogram could be used to assess the risk of poor prognosis in children with E coli meningitis by clinicians.


Asunto(s)
Meningitis por Escherichia coli , Meningitis , Humanos , Niño , Lactante , Nomogramas , Meningitis por Escherichia coli/complicaciones , Estudios Retrospectivos , Escherichia coli , Reproducibilidad de los Resultados , Pronóstico
6.
BMJ Case Rep ; 16(8)2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37643819

RESUMEN

Strongyloidiasis, a helminth infection caused by Strongyloides stercoralis, can be complicated by hyperinfection, especially in the setting of immunosuppression; however, many patients go undiagnosed. One clue to diagnosis is unexplained gram-negative bacteraemia or meningitis in patients who are immunosuppressed. Serology can be helpful but may be negative in these patients who are immunocompromised.We present the case of a white cisgender man from Central America in his 40s, living with HIV, with a CD4 count of 77 cells/µL. He was diagnosed with Strongyloides hyperinfection after an increase in his steroid dose. He also had Escherichia coli meningitis and bacteraemia. Strongyloidiasis was diagnosed by stool microscopy despite a negative serology test.This case highlights the challenges in diagnosing strongyloidiasis in the setting of immunosuppression. A high index of clinical suspicion is warranted for patients living with HIV on high-dose corticosteroids. Up to three stool microscopy studies for Strongyloides should be sent in addition to serology.


Asunto(s)
Bacteriemia , Infecciones por VIH , Meningitis por Escherichia coli , Strongyloides stercoralis , Estrongiloidiasis , Masculino , Animales , Humanos , Estrongiloidiasis/complicaciones , Estrongiloidiasis/diagnóstico , Estrongiloidiasis/tratamiento farmacológico , Bacteriemia/tratamiento farmacológico , Infecciones por VIH/complicaciones
7.
Int J Mol Sci ; 24(12)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37373064

RESUMEN

Bacterial meningitis is a devastating disease occurring worldwide, with up to half of survivors left with permanent neurological sequelae. Neonatal meningitis-causing Escherichia coli (NMEC) is the most common Gram-negative bacillary organism that causes meningitis, particularly during the neonatal period. Here, RNA-seq transcriptional profiles of microglia in response to NMEC infection show that microglia are activated to produce inflammatory factors. In addition, we found that the secretion of inflammatory factors is a double-edged sword that promotes polymorphonuclear neutrophil (PMN) recruitment to the brain to clear the pathogens but, at the same time, induces neuronal damage, which may be related to the neurological sequelae. New neuroprotective therapeutic strategies must be developed for the treatment of acute bacterial meningitis. We found that transforming growth factor-ß (TGF-ß) may be a strong candidate in the treatment of acute bacterial meningitis, as it shows a therapeutic effect on bacterial-meningitis-induced brain damage. Prevention of disease and early initiation of the appropriate treatment in patients with suspected or proven bacterial meningitis are the key factors in reducing morbidity and mortality. Novel antibiotic and adjuvant treatment strategies must be developed, and the main goal for new therapies will be dampening the inflammatory response. Based on this view, our findings may help develop novel strategies for bacterial meningitis treatment.


Asunto(s)
Infecciones por Escherichia coli , Meningitis Bacterianas , Meningitis por Escherichia coli , Recién Nacido , Humanos , Microglía , Meningitis por Escherichia coli/microbiología , Meningitis Bacterianas/microbiología , Infecciones por Escherichia coli/microbiología , Escherichia coli
9.
FASEB J ; 36(3): e22197, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35147989

RESUMEN

Neonatal meningitis-associated Escherichia coli (NMEC) is among the leading causes of bacterial meningitis and sepsis in newborn infants. Several virulence factors have been identified as common among NMEC, and have been shown to play an important role in the development of bacteremia and/or meningitis. However, there is significant variability in virulence factor expression between NMEC isolates, and relatively little research has been done to assess the impact of variable virulence factor expression on immune cell activation and the outcome of infection. Here, we investigated the role of NMEC strain-dependent P2X receptor (P2XR) signaling on the outcome of infection in neonatal mice. We found that alpha-hemolysin (HlyA)-expressing NMEC (HlyA+ ) induced robust P2XR-dependent macrophage cell death in vitro, while HlyA- NMEC did not. P2XR-dependent cell death was inflammasome independent, suggesting an uncoupling of P2XR and inflammasome activation in the context of NMEC infection. In vivo inhibition of P2XRs was associated with increased mortality in neonatal mice infected with HlyA+ NMEC, but had no effect on the survival of neonatal mice infected with HlyA- NMEC. Furthermore, we found that P2XR-dependent protection against HlyA+ NMEC in vivo required macrophages, but not neutrophils or NLRP3. Taken together, these data suggest that HlyA+ NMEC activates P2XRs which in turn confers macrophage-dependent protection against infection in neonates. In addition, our findings indicate that strain-dependent virulence factor expression should be taken into account when studying the immune response to NMEC.


Asunto(s)
Proteínas de Escherichia coli/toxicidad , Proteínas Hemolisinas/toxicidad , Inflamasomas/metabolismo , Meningitis por Escherichia coli/metabolismo , Sepsis Neonatal/metabolismo , Receptores Purinérgicos P2X/metabolismo , Animales , Células Cultivadas , Escherichia coli K12 , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Macrófagos/metabolismo , Meningitis por Escherichia coli/microbiología , Ratones , Ratones Endogámicos C57BL , Sepsis Neonatal/microbiología , Receptores Purinérgicos P2X/genética
10.
Int J Mol Sci ; 24(1)2022 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-36613745

RESUMEN

Avian meningitis Escherichia coli (E. coli) can cause acute bacterial meningitis which threatens poultry health, causes great economic losses in the poultry industry, and has recently been speculated as a potential zoonotic pathogen. Melatonin can counteract bacterial meningitis-induced disruption of the blood-brain barrier (BBB), neuroinflammation, and reduce mortality. There are increasing data showing that melatonin's beneficial effects on bacterial meningitis are associated with intestinal microbiota. In this study, our data showed that melatonin alleviated neurological symptoms, enhanced survival rate, protected the integrity of the BBB, reduced the bacterial load in various tissues and blood, and inhibited inflammation and neutrophil infiltration of brain tissue in an APEC TW-XM-meningitis mice model. The results of 16S rRNA showed that melatonin pretreatment significantly maintained the composition of intestinal microbiota in APEC-meningitis mice. The abundance and diversity of intestinal microbiota were disturbed in APEC TW-XM-meningitis mice, with a decreased ratio of Firmicutes to Bacteroides and an increased the abundance of Proteobacteria. Melatonin pretreatment could significantly improve the composition and abundance of harmful bacteria and alleviate the decreased abundance of beneficial bacteria. Importantly, melatonin failed to affect the meningitis neurologic symptoms caused by APEC TW-XM infection in antibiotic-pretreated mice. In conclusion, the results suggest that melatonin can effectively prevent meningitis induced by APEC TW-XM infection in mice, depending on the intestinal microbiota. This finding is helpful to further explore the specific target mechanism of melatonin-mediated intestinal microbiota in the prevention of and protection against Escherichia coli meningitis.


Asunto(s)
Infecciones por Escherichia coli , Microbioma Gastrointestinal , Melatonina , Meningitis Bacterianas , Meningitis por Escherichia coli , Enfermedades de las Aves de Corral , Animales , Ratones , Meningitis por Escherichia coli/tratamiento farmacológico , Escherichia coli/genética , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Melatonina/farmacología , Melatonina/uso terapéutico , ARN Ribosómico 16S/genética , Meningitis Bacterianas/tratamiento farmacológico , Enfermedades de las Aves de Corral/microbiología , Pollos/genética
11.
12.
Acta Neurol Taiwan ; 30(4): 141-150, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34841499

RESUMEN

BACKGROUND: To examine the clinical characteristics and therapeutic outcome of Escherichia (E.) coli adult bacterial meningitis (ABM). METHODS: The demographic data, clinical and laboratory features and therapeutic outcome of 25 E. coli ABM patients were examined retrospectively. The clinical features of the reported E. coli ABM cases were also included for analysis. RESULTS: The 25 E. coli ABM patients included 12 women and 13 men, aged 33-78 years (mean= 59.9). Of these 25 patients, 13 had a postneurosurgical state as the underlying condition. As to the underlying medical conditions, diabetes mellitus was the most common, found in 9 of the 25 cases. Of the clinical manifestation, severe neurologic manifestations including altered consciousness (19), hydrocephalus (10), seizure (7) acute/subacute cerebral infarct (5), brain abscess (2), subdural empyema (1) and spinal abscess (1) were found, and the other clinical features included fever (21), septic shock (8), bacteremia (6) and hyponatremia (3). With treatment, the mortality rate was more than 44.0% and the presence of septic shock was a significant prognostic factor. With literature review, 29 community-acquired and 12 postneurosurgical E. coli ABM cases were enrolled, and severe neurologic manifestation and high mortality rate were also found. CONCLUSIONS: This preliminary overview of E. coli ABM revealed the underlying conditions, severe neurologic manifestation and high mortality rate. Further large-scale, prospective study is needed for a better delineation of this specific infectious syndrome of adult E. coli meningitis.


Asunto(s)
Meningitis Bacterianas , Meningitis por Escherichia coli , Adulto , Escherichia coli , Femenino , Humanos , Masculino , Meningitis Bacterianas/terapia , Meningitis por Escherichia coli/terapia , Estudios Retrospectivos , Resultado del Tratamiento
13.
Front Immunol ; 12: 745854, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721415

RESUMEN

Alpha 7 nicotinic acetylcholine receptor (α7 nAChR) is critical for the pathogenesis of Escherichia coli (E. coli) K1 meningitis, a severe central nervous system infection of the neonates. However, little is known about how E. coli K1 manipulates α7 nAChR signaling. Here, through employing immortalized cell lines, animal models, and human transcriptional analysis, we showed that E. coli K1 infection triggers releasing of secreted Ly6/Plaur domain containing 1 (SLURP1), an endogenous α7 nAChR ligand. Exogenous supplement of SLURP1, combined with SLURP1 knockdown or overexpression cell lines, showed that SLURP1 is required for E. coli K1 invasion and neutrophils migrating across the blood-brain barrier (BBB). Furthermore, we found that SLURP1 is required for E. coli K1-induced α7 nAChR activation. Finally, the promoting effects of SLURP1 on the pathogenesis of E. coli K1 meningitis was significantly abolished in the α7 nAChR knockout mice. These results reveal that E. coli K1 exploits SLURP1 to activate α7 nAChR and facilitate its pathogenesis, and blocking SLURP1-α7 nAChR interaction might represent a novel therapeutic strategy for E. coli K1 meningitis.


Asunto(s)
Antígenos Ly/fisiología , Barrera Hematoencefálica , Infecciones por Escherichia coli/microbiología , Escherichia coli/fisiología , Meningitis por Escherichia coli/fisiopatología , Activador de Plasminógeno de Tipo Uroquinasa/fisiología , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Animales , Antígenos Ly/genética , Línea Celular , Líquido Cefalorraquídeo/microbiología , Células Endoteliales/microbiología , Escherichia coli/aislamiento & purificación , Hipocampo/metabolismo , Interacciones Huésped-Patógeno , Humanos , Recién Nacido , Memantina/farmacología , Meningitis por Escherichia coli/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/fisiología , Proteínas Recombinantes/metabolismo , Organismos Libres de Patógenos Específicos , Activador de Plasminógeno de Tipo Uroquinasa/genética , Receptor Nicotínico de Acetilcolina alfa 7/antagonistas & inhibidores , Receptor Nicotínico de Acetilcolina alfa 7/deficiencia
14.
Microbiology (Reading) ; 167(10)2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34623236

RESUMEN

Appropriate interpretation of environmental signals facilitates niche specificity in pathogenic bacteria. However, the responses of niche-specific pathogens to common host signals are poorly understood. d-Serine (d-ser) is a toxic metabolite present in highly variable concentrations at different colonization sites within the human host that we previously found is capable of inducing changes in gene expression. In this study, we made the striking observation that the global transcriptional response of three Escherichia coli pathotypes - enterohaemorrhagic E. coli (EHEC), uropathogenic E. coli (UPEC) and neonatal meningitis-associated E. coli (NMEC) - to d-ser was highly distinct. In fact, we identified no single differentially expressed gene common to all three strains. We observed the induction of ribosome-associated genes in extraintestinal pathogens UPEC and NMEC only, and the induction of purine metabolism genes in gut-restricted EHEC, and UPEC indicating distinct transcriptional responses to a common signal. UPEC and NMEC encode dsdCXA - a genetic locus required for detoxification and hence normal growth in the presence of d-ser. Specific transcriptional responses were induced in strains accumulating d-ser (WT EHEC and UPEC/NMEC mutants lacking the d-ser-responsive transcriptional activator DsdC), corroborating the notion that d-ser is an unfavourable metabolite if not metabolized. Importantly, many of the UPEC-associated transcriptome alterations correlate with published data on the urinary transcriptome, supporting the hypothesis that d-ser sensing forms a key part of urinary niche adaptation in this pathotype. Collectively, our results demonstrate distinct pleiotropic responses to a common metabolite in diverse E. coli pathotypes, with important implications for niche selectivity.


Asunto(s)
Escherichia coli/genética , Serina/metabolismo , Transcriptoma , Escherichia coli/crecimiento & desarrollo , Escherichia coli/aislamiento & purificación , Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , Humanos , Meningitis por Escherichia coli/microbiología , Especificidad de la Especie , Infecciones Urinarias/microbiología
15.
Microb Pathog ; 160: 105199, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34560248

RESUMEN

Neonatal bacterial meningitis is a life-threatening disease in newborns, and neonatal meningitis Escherichia coli (NMEC) is the second most frequent bacteria causing this disease worldwide. In order to further understand the characteristics of this pathogen, an E. coli isolate W224 N from newborns with meningitis was sequenced for detailed genetic characterization and the virulence was tested by a series of phenotypic experiments. W224 N has a circular chromosome and three plasmids. It belongs to ST95 and the serotype is O18:H7. Comparative genomic analysis showed that W224 N was closely related to E. coli neonatal meningitis isolates RS218 and NMEC O18. There are 11 genomic islands in W224 N and most of the GIs are specific to W224 N. W224 N has most of the virulence factors other neonatal meningitis isolates have. The virulence genes located both on the genome and plasmid. At the same time, we found a virulence factor cdiA only present in W224 N but absent in the other five genomes analyzed. In vitro experiment showed that W224 N has strong serum resistance ability, low biofilm formation ability and high flagellar motility. It also has a very strong toxicity to mice and amoeba. The whole genome as well as in vitro and in vivo experiments showed that W224 N is a high virulent strain. The results can help us better learn about the pathogenicity of neonatal meningitis E. coli.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli/genética , Genoma Bacteriano , Meningitis por Escherichia coli , Animales , Escherichia coli/patogenicidad , Proteínas de la Membrana , Meningitis por Escherichia coli/microbiología , Ratones , Virulencia , Factores de Virulencia/genética
16.
J Vis Exp ; (170)2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33970148

RESUMEN

Escherichia coli (E. coli) is the most common Gram-negative bacteria causing neonatal meningitis. The occurrence of bacteremia and bacterial penetration through the blood-brain barrier are indispensable steps for the development of E. coli meningitis. Reactive oxygen species (ROS) represent the major bactericidal mechanisms of neutrophils to destroy the invaded pathogens. In this protocol, the time-dependent intracellular ROS production in neutrophils infected with meningitic E. coli was quantified using fluorescent ROS probes detected by a real-time fluorescence microplate reader. This method may also be applied to the assessment of ROS production in mammalian cells during pathogen-host interactions.


Asunto(s)
Meningitis por Escherichia coli/microbiología , Neutrófilos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Humanos
17.
J Neuroinflammation ; 18(1): 114, 2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-33985523

RESUMEN

BACKGROUND: Escherichia coli is the most common Gram-negative bacterium causing meningitis, and E. coli meningitis is associated with high mortality and morbidity throughout the world. Our previous study showed that E. coli can colonize the brain and cause neuroinflammation. Increasing evidence supports the involvement of miRNAs as key regulators of neuroinflammation. However, it is not clear whether these molecules participate in the regulation of meningitic E. coli-mediated neuroinflammation. METHODS: The levels of miR-155 and miR-146a, as well as their precursors, in E. coli-infected astrocytes were measured using quantitative real-time PCR (qPCR). Overexpression and knockdown studies of miR-155 and miR-146a were performed to observe the effects on bacterial loads, cytokines, chemokines, and NF-κB signaling pathways. Bioinformatics methods were utilized to predict the target genes, and these target genes were validated using qPCR, Western blotting, and luciferase reporter system. In vivo knockdown of miR-155 and miR-146a was carried out to observe the effects on bacterial loads, inflammatory genes, astrocyte activation, microglia activation, and survival in a mouse model. RESULTS: The levels of miR-155, miR-146a, and their precursors were significantly increased in astrocytes during E. coli infection. miR-155 and miR-146a were induced by the NF-κB-p65 signaling pathway upon infection. Overexpressing and inhibiting miR-155 and miR-146a in astrocytes did not affect the bacterial loads. Further, the in vitro overexpression of miR-155 and miR-146a suppressed the E. coli-induced inflammatory response, whereas the inhibition of miR-155 and miR-146a enhanced it. Mechanistically, miR-155 inhibited TAB2, and miR-146a targeted IRAK1 and TRAF6; therefore, they functioned collaboratively to modulate TLR-mediated NF-κB signaling. In addition, both miR-155 and miR-146a could regulate the EGFR-NF-κB signaling pathway. Finally, the in vivo suppression of E. coli-induced miR-155 and miR-146a further promoted the production of inflammatory cytokines, aggravated astrocyte and microglia activation, and decreased mouse survival time, without affecting the bacterial loads in the blood and brain. CONCLUSIONS: E. coli infection induced miR-155 and miR-146a, which collectively regulated bacteria-triggered neuroinflammatory responses through negative feedback regulation involving the TLR-mediated NF-κB and EGFR-NF-κB signaling pathways, thus protecting the central nervous system from further neuroinflammatory damage.


Asunto(s)
Inflamación/microbiología , Meningitis por Escherichia coli/inmunología , Meningitis por Escherichia coli/metabolismo , MicroARNs/inmunología , MicroARNs/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Antagomirs , Astrocitos/inmunología , Astrocitos/microbiología , Línea Celular , Escherichia coli/inmunología , Inflamación/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1 , Ratones , FN-kappa B/metabolismo , Transducción de Señal , Factor 6 Asociado a Receptor de TNF/metabolismo
18.
BMJ Case Rep ; 14(3)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33674294

RESUMEN

A woman in her 70s presented to the emergency department with fever, fluctuating cognition and headache. A detailed examination revealed neurological weakness to the lower limbs with atonia and areflexia, leading to a diagnosis of bacterial meningitis, alongside a concurrent COVID-19 infection. The patient required critical care escalation for respiratory support. After stepdown to a rehabilitation ward, she had difficulties communicating due to new aphonia, hearing loss and left third nerve palsy. The team used written communication with the patient, and with this the patient was able to signal neurological deterioration. Another neurological examination noted a different pattern of weakness to the lower limbs, along with new urinary retention, and spinal arachnoiditis was identified. After more than 10 weeks in the hospital, the patient was discharged. Throughout this case, there were multiple handovers between teams and specialties, all of which were underpinned by good communication and examination to achieve the best care.


Asunto(s)
COVID-19/complicaciones , Meningitis por Escherichia coli/complicaciones , Anciano , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , COVID-19/diagnóstico por imagen , COVID-19/terapia , Ceftriaxona/uso terapéutico , Coinfección , Terapia Combinada , Comunicación , Confusión/etiología , Cuidados Críticos , Diagnóstico Diferencial , Femenino , Fiebre/etiología , Cefalea/etiología , Humanos , Meningitis por Escherichia coli/diagnóstico por imagen , Meningitis por Escherichia coli/tratamiento farmacológico , Grupo de Atención al Paciente , Modalidades de Fisioterapia , Relaciones Médico-Paciente , Respiración Artificial , SARS-CoV-2 , Resultado del Tratamiento
19.
ACS Infect Dis ; 7(4): 777-789, 2021 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-33723986

RESUMEN

Meningitic Escherichia coli can infiltrate the central nervous system (CNS), consequently increasing the levels of proinflammatory cytokines and chemokines and deteriorating the integrity of the blood-brain barrier (BBB). Resveratrol has emerged in recent years as a compound with antioxidant and anti-inflammatory properties. However, it is still unknown how resveratrol affects meningitic E. coli-induced CNS dysfunction. Here, by using in vivo and in vitro BBB models, we demonstrated that resveratrol treatment significantly inhibited meningitic E. coli invasion of the BBB, protected the integrity of the BBB, and reduced neuroinflammation and lethality. In mechanism, resveratrol inhibited bacterial penetration of the BBB by attenuating the upregulation of caveolin-1 (CAV-1), a class of lipid rafts maintaining endothelial cell function. Resveratrol treatment also maintained BBB permeability by suppressing the ERK1/2-VEGFA signaling cascade. In vivo treatment of resveratrol decreased the production of inflammatory cytokines and improved the survival rate in mice challenged with meningitic E. coli. These findings collectively indicated that resveratrol could attenuate meningitic E. coli-induced CNS injury, which might constitute a new approach for future prevention and treatment of E. coli meningitis.


Asunto(s)
Barrera Hematoencefálica , Meningitis por Escherichia coli , Animales , Células Endoteliales , Escherichia coli , Ratones , Resveratrol/farmacología
20.
Pediatr. catalan ; 81(1): 14-16, ene.-mar. 2021. ilus
Artículo en Español | IBECS | ID: ibc-202629

RESUMEN

INTRODUCCIÓ: Un cefalohematoma és una col·lecció de sang sota el periosti del crani secundària a un traumatisme del part. Afecta entre l'1% I el 2% dels nadons nascuts per un part vaginal I entre el 3% I el 4% dels nascuts mitjançant un part instrumentat. Solen ser benignes I autolimitats, I es resolen espontàniament al cap d'unes setmanes, però alguns casos poden anar acompanyats d'anèmia, hiperbilirubinèmia o fractura cranial, complicar-se amb una calcificació o, rarament, infectar-se. CAS CLINIC: Nounat a terme de 9 dies de vida amb un cefalohematoma present des del naixement que va augmentar de mida després de tenir febre I infectar-se per Escherichia coli, suposadament per l'extensió d'una bacterièmia, I que es va acompanyar d'una meningitis asèptica (pleocitosi) que es va considerar secundària a una osteomielitis per contigüitat. El pacient es va tractar amb antibiòtics I desbridament quirúrgic, I no va tenir seqüeles. COMENTARIS: Cal tenir present que els cefalohematomes, tot I que habitualment tenen un curs autolimitat I una bona evolució, són un lloc potencial d'infecció, I que cal sospitar I descartar la infecció en un pacient amb febre I l'existència prèvia d'un cefalohematoma. S'han descrit casos de meningitis associats a cefalohematoma, però, fins on sabem, només un de meningitis asèptica com el descrit I que es va considerar, a diferència del que presentem, secundària a un retard en la recollida del líquid cefaloraquidi després d'iniciada l'antibioteràpia


INTRODUCCIÓN: Un cefalohematoma es una colección de sangre debajo del periostio del cráneo secundaria a un traumatismo del parto. Afecta a entre el 1% y el 2% de los neonatos nacidos mediante un parto vaginal y a entre el 3% y el 4% de los nacidos mediante un parto instrumentado. Suelen ser benignos, autolimitados y resolverse espontáneamente en semanas, pero en algunos casos se pueden acompañar de anemia, hiperbilirrubinemia o fractura craneal, complicarse con una calcificación o, raramente, infectarse. CASO CLÍNICO: Recién nacido a término de 9 días de vida con un cefalohematoma presente desde el nacimiento que aumentó de tamaño tres haber tenido fiebre e infectarse por Escherichia coli, supuestamente por la extensión de una bacteriemia, y que se acompañó de una meningitis aséptica (pleocitosis) que se consideró secundaria a una osteomielitis por contigüidad. El paciente se trató con antibióticos y desbridamiento quirúrgico y no tuvo secuelas. COMENTARIOS: Debemos tener en cuenta que los cefalohematomas, a pesar de que habitualmente tienen un curso autolimitado y una buena evolución, son un lugar potencial de infección, y que hay que sospechar y descartar la infección en un paciente con fiebre y la existencia de un cefalohematoma previo. Se han descrito algunos casos de meningitis asociados a cefalohematoma, pero hasta donde sabemos solo uno de meningitis aséptica como el descrito y que se consideró, a diferencia del que presentamos, secundaria a un retraso en la recogida del líquido cefalorraquídeo tras el inicio de la antibioterapia


INTRODUCTION: A cephalohematoma is a collection of blood below the periosteum of the skull due to birth trauma. It affects 1-2% of spontaneous vaginal deliveries and 3-4% of instrument-assisted deliveries. It is usually a self-limiting, benign condition which resorbs within weeks. A small proportion of cases can be accompanied by anemia, hyperbilirubinemia or a skull fracture, or be complicated by calcification or rarely by infection. CASE REPORT: 9-day-old full term neonate with a cephalohematoma present at birth that enlarged after the cephalohematoma got infected by Escherichia coli during a septic episode. Aseptic meningitis (pleocytosis) was assumed to be due to contiguous osteomyelitis. The patient was successfully treated with antibiotics and surgical debridement and showed no sequelae. COMMENTS: Clinicians should be aware that even though cephalohematomas are usually a benign, self-limiting condition, they are a potential site of infection. Infection must be suspected and ruled out in a patient with fever and a pre-existing cephalohematoma. A few cases of meningitis accompanying an infected cephalohematoma have been reported, although, to our knowledge, there is only one report of an associated aseptic meningitis. In contrast to the patient we present, in the other reported case lumbar puncture was performed 24 hours after onset of antibiotic treatment, which was suggested as the reason for the cerebrospinal fluid to be sterile


Asunto(s)
Humanos , Masculino , Recién Nacido , Hematoma Epidural Craneal/diagnóstico por imagen , Hematoma Epidural Craneal/terapia , Meningitis por Escherichia coli/etiología , Infecciones por Escherichia coli/etiología , Forceps Obstétrico/efectos adversos , Meningitis por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/tratamiento farmacológico , Hematoma Epidural Craneal/etiología , Antibacterianos/uso terapéutico , Desbridamiento/métodos , Cráneo/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Succión/métodos , Cefotaxima/uso terapéutico
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