TNF-α increases invasion and proliferation of enteroinvasive Escherichia coli in epithellal cell monolayers

The mechanism by which enteropathogenic Escherichia coli (EPEC) causes diarrhea remains elusive. Several alterations within the host cell have been demonstrated to occur following EPEC attachment including increases in intracellular Ca2+ concentration and rearrangement and phosphorylation of several cytoskeletal proteins. The consequences of these intracellular perturbations on host cell function, however, have not been determined. The aim of this study was to examine the effect of EPEC adherence on intestinal epithelial barrier function. T84 cell monolayers were infected with either wild-type EPEC or a nonadherent isogenic derivative. Transepithelial electrical resistance, a measure of barrier function, decreased 33.5 +/- 6.4% after a 6-h incubation with the wild-type strain. Electron microscopy revealed ultrastructurally normal cells, and lactate dehydrogenase release assays failed to demonstrate cytotoxicity. Dual 22Na+ and [3H]mannitol flux studies localized the permeability defect to tight junctions. In addition, cumulative flux of the paracellular marker mannitol was four- to fivefold greater across monolayers infected with wild-type EPEC. Sequestration of intracellular calcium stores by dantrolene completely abrogated the resistance drop associated with EPEC attachment. These data demonstrate that adherence of EPEC to intestinal epithelial cell monolayers disrupts tight junction barrier function via a calcium-requiring event.

Download Full-text

Inhibitory effects of Lepidium sativum polysaccharide extracts on TNF-α production in Escherichia coli-stimulated mouse

3 Biotech ◽

10.1007/s13205-018-1309-9 ◽

2018 ◽

Vol 8 (6) ◽

Cited By ~ 1

Author(s):

Ajaz Ahmad ◽

Basit Latief Jan ◽

Mohammad Raish ◽

Khalid M. Alkharfy ◽

Abdul Ahad ◽

...

Keyword(s):

Escherichia Coli ◽

Lepidium Sativum ◽

Inhibitory Effects ◽

Tnf Α

Download Full-text

Lacticaseibacillus paracasei NK112 mitigates Escherichia coli-induced depression and cognitive impairment in mice by regulating IL-6 expression and gut microbiota

Beneficial Microbes ◽

10.3920/bm2020.0109 ◽

2021 ◽

pp. 1-12

Author(s):

S.-W. Yun ◽

J.-K. Kim ◽

M.J. Han ◽

D.-H. Kim

Keyword(s):

Escherichia Coli ◽

Cognitive Impairment ◽

Gut Microbiota ◽

Psychiatric Disorders ◽

Myeloperoxidase Activity ◽

Bdnf Expression ◽

Strain Collection ◽

Tnf Α ◽

Faecal Bacteria ◽

Anxiety Depression

The gut microbiota communicates with the brain through microbiota-gut-brain (MGB) and hypothalamus-pituitary-adrenal (HPA) axes and other pathways. Excessive expression of interleukin (IL)-6 is closely associated with the occurrence of the psychiatric disorders depression and dementia. Therefore, to understand whether IL-6 expression-suppressing probiotics could alleviate psychiatric disorders, we isolated IL-6 expression-inhibiting Lacticaseibacillus paracasei (formerly Lactobacillus paracasei) NK112 from the human faecal bacteria strain collection (Neurobiota Research Center, Seoul, Korea) and examined its therapeutic effect for the depression and cognitive impairment in mice. C57 BL/6J mice with depression and cognitive impairment were prepared by exposure to Escherichia coli K1. Oral gavage of NK112 significantly alleviated K1-induced anxious, depressive, and memory-impaired behaviours in the elevated plus maze, tail-suspension and Y-maze tasks, IL-1β, IL-6, and tumour necrosis factor (TNF)-α expression, and nuclear factor kappa beta (NF-κB) activation in the hippocampus, while K1-suppressed brain-derived neurotrophic factor (BDNF) expression increased. Treatment with NK112 also improved K1-induced myeloperoxidase activity, IL-6 and TNF-α expression, and NF-κB activation in the colon and reduced K1-induced Proteobacteria population in the gut microbiota. Heat-killed NK112 and its lysate supernatant, and precipitate fractions also improved anxiety/depression, cognitive impairment, and colitis in mice. In conclusion, NK112, even if heat-killed or lysed, alleviated K1 stress-induced colitis, anxiety/depression, and cognitive impairment by suppressing IL-6, TNF-α, and BDNF expression through the regulation of gut microbiota and NF-κB activation.

Download Full-text

An Engineered Infected Epidermis Model for In Vitro Study of the Skin’s Pro-Inflammatory Response

Micromachines ◽

10.3390/mi11020227 ◽

2020 ◽

Vol 11 (2) ◽

pp. 227 ◽

Cited By ~ 1

Author(s):

Maryam Jahanshahi ◽

David Hamdi ◽

Brent Godau ◽

Ehsan Samiei ◽

Carla Sanchez-Lafuente ◽

...

Keyword(s):

Escherichia Coli ◽

Inflammatory Response ◽

Human Skin ◽

Electrical Resistance ◽

Drug Testing ◽

Healing Process ◽

Tnf Α ◽

Hydrogel Matrix ◽

Significant Difference

Wound infection is a major clinical challenge that can significantly delay the healing process, can create pain, and requires prolonged hospital stays. Pre-clinical research to evaluate new drugs normally involves animals. However, ethical concerns, cost, and the challenges associated with interspecies variation remain major obstacles. Tissue engineering enables the development of in vitro human skin models for drug testing. However, existing engineered skin models are representative of healthy human skin and its normal functions. This paper presents a functional infected epidermis model that consists of a multilayer epidermis structure formed at an air-liquid interface on a hydrogel matrix and a three-dimensionally (3D) printed vascular-like network. The function of the engineered epidermis is evaluated by the expression of the terminal differentiation marker, filaggrin, and the barrier function of the epidermis model using the electrical resistance and permeability across the epidermal layer. The results showed that the multilayer structure enhances the electrical resistance by 40% and decreased the drug permeation by 16.9% in the epidermis model compared to the monolayer cell culture on gelatin. We infect the model with Escherichia coli to study the inflammatory response of keratinocytes by measuring the expression level of pro-inflammatory cytokines (interleukin 1 beta and tumor necrosis factor alpha). After 24 h of exposure to Escherichia coli, the level of IL-1β and TNF-α in control samples were 125 ± 78 and 920 ± 187 pg/mL respectively, while in infected samples, they were 1429 ± 101 and 2155.5 ± 279 pg/mL respectively. However, in ciprofloxacin-treated samples the levels of IL-1β and TNF-α without significant difference with respect to the control reached to 246 ± 87 and 1141.5 ± 97 pg/mL respectively. The robust fabrication procedure and functionality of this model suggest that the model has great potential for modeling wound infections and drug testing.

Download Full-text

Administration of Escherichia coli endotoxin to rat increases liver mass and hepatocyte volume in vivo

Biochemical Journal ◽

10.1042/bj3130479 ◽

1996 ◽

Vol 313 (2) ◽

pp. 479-486 ◽

Cited By ~ 20

Author(s):

Dalong QIAN ◽

John T. BROSNAN

Keyword(s):

Escherichia Coli ◽

Intraperitoneal Administration ◽

Polyclonal Antiserum ◽

Metabolic Effects ◽

Morphometric Study ◽

Liver Mass ◽

Hepatic Mass ◽

Tnf Α ◽

Factor Α

We have established, in vivo, an increase in liver mass and hepatocyte volume after a single intraperitoneal administration, to fasted rats, of Escherichia coli lipopolysaccharide (0127:B8) at 3 mg/kg. The phenomenon was time- and dose-dependent and could be prevented by treatment with polyclonal antiserum against tumour necrosis factor-α (TNF-α) before the endotoxin injection. Endotoxin caused an increase of 26% in the hepatic mass compared with fasted controls at 24 h. An increase of 27% in the hepatic water content underlay the altered hepatic mass which could not be accounted for by a change in the volume of hepatic blood and/or interstitial fluid (measured in vivo), suggesting an expansion in the hepatocellular volume. This is supported by an increase of 25% in the K+ content of the endotoxic livers. Morphometric study confirmed a 15% increase in hepatocyte volume after endotoxin administration. The data are discussed in the light of possible metabolic effects of increased hepatocyte volume.

Download Full-text

Escherichia coli and TNF-α Modulate Macrophage Phagocytosis of Candida glabrata

Journal of Surgical Research ◽

10.1016/j.jss.2008.07.022 ◽

2009 ◽

Vol 155 (2) ◽

pp. 217-224 ◽

Cited By ~ 16

Author(s):

Donavon J. Hess ◽

Michelle J. Henry-Stanley ◽

Catherine M. Bendel ◽

Bin Zhang ◽

Mary-Alice Johnson ◽

...

Keyword(s):

Escherichia Coli ◽

Candida Glabrata ◽

Macrophage Phagocytosis ◽

Tnf Α

Download Full-text

INTRACELLULAR PERSISTENCE OF ENTEROAGGREGATIVE ESCHERICHIA COLI INDUCES A PROINFLAMMATORY CYTOKINES SECRETION IN INTESTINAL EPITHELIAL T84 CELLS

Arquivos de Gastroenterologia ◽

10.1590/s0004-2803.201800000-23 ◽

2018 ◽

Vol 55 (2) ◽

pp. 133-137

Author(s):

Ricardo Luís Lopes BRAGA ◽

Ana Claudia Machado PEREIRA ◽

Andréa Fonseca FERREIRA ◽

Ana Cláudia de Paula ROSA ◽

Wânia Ferraz PEREIRA-MANFRO

Keyword(s):

Escherichia Coli ◽

Immune Response ◽

Virulence Genes ◽

Sandwich Elisa ◽

Survival Rates ◽

Epithelial Cell Line ◽

Intestinal Epithelial ◽

T84 Cells ◽

Production Methods ◽

Tnf Α

ABSTRACT BACKGROUND: The competence of enteroaggregative Escherichia coli (EAEC) to adhere to the intestinal epithelium of the host is a key role to the colonization and disease development. The virulence genes are crucial for EAEC pathogenicity during adherence, internalization and persistence in the host. The overwhelming majority of antigen encounters in a host occurs on the intestine surface, which is considered a part of innate mucosal immunity. Intestinal epithelial cells (IECs) can be activated by microorganisms and induce an immune response. OBJECTIVE: The present study investigated the interaction of invasive EAEC strains with T84 intestinal epithelial cell line in respect to bacterial invasiveness, persistence and cytokines production. METHODS: We evaluated intracellular persistence of invasive EAEC strains (H92/3, I49/3 and the prototype 042) and production of cytokines by sandwich ELISA in T84 cells upon 24 hours of infection. RESULTS: The survival rates of the prototype 042 was 0.5x103 CFU/mL while survival of I49/3 and H92/3 reached 3.2x103 CFU/mL and 1.4x103 CFU/mL, respectively. Infection with all EAEC strains tested induced significant amounts of IL-8, IL-6 and TNF-α compared to uninfected T84 cells. CONCLUSION: These data showed that infection by invasive EAEC induce a proinflammatory immune response in intestinal epithelial T84 cells.

Download Full-text

Proinflammatory cytokines tumor necrosis factor-α and interferon-γ alter tight junction structure and function in the rat parotid gland Par-C10 cell line

AJP Cell Physiology ◽

10.1152/ajpcell.00144.2008 ◽

2008 ◽

Vol 295 (5) ◽

pp. C1191-C1201 ◽

Cited By ~ 77

Author(s):

Olga J. Baker ◽

Jean M. Camden ◽

Robert S. Redman ◽

Jonathan E. Jones ◽

Cheikh I. Seye ◽

...

Keyword(s):

Receptor Agonist ◽

Interferon Γ ◽

Anion Secretion ◽

Cell Monolayers ◽

Tnf Α ◽

Rat Parotid Gland ◽

Ifn Γ ◽

Rat Parotid ◽

Factor Α ◽

Necrosis Factor

Sjögren's syndrome (SS) is an autoimmune disorder characterized by inflammation and dysfunction of salivary glands, resulting in impaired secretory function. The production of the proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) is elevated in exocrine glands of patients with SS, although little is known about the effects of these cytokines on salivary epithelial cell functions necessary for saliva secretion, including tight junction (TJ) integrity and the establishment of transepithelial ion gradients. The present study demonstrates that chronic exposure of polarized rat parotid gland (Par-C10) epithelial cell monolayers to TNF-α and IFN-γ decreases transepithelial resistance (TER) and anion secretion, as measured by changes in short-circuit current ( Isc) induced by carbachol, a muscarinic cholinergic receptor agonist, or UTP, a P2Y2 nucleotide receptor agonist. In contrast, TNF-α and IFN-γ had no effect on agonist-induced increases in the intracellular calcium concentration [Ca2+]i in Par-C10 cells. Furthermore, treatment of Par-C10 cell monolayers with TNF-α and IFN-γ increased paracellular permeability to normally impermeant proteins, altered cell and TJ morphology, and downregulated the expression of the TJ protein, claudin-1, but not other TJ proteins expressed in Par-C10 cells. The decreases in TER, agonist-induced transepithelial anion secretion, and claudin-1 expression caused by TNF-α, but not IFN-γ, were reversible by incubation of Par-C10 cell monolayers with cytokine-free medium for 24 h, indicating that IFN-γ causes irreversible inhibition of cellular activities associated with fluid secretion in salivary glands. Our results suggest that cytokine production is an important contributor to secretory dysfunction in SS by disrupting TJ integrity of salivary epithelium.

Download Full-text

Rapid modulation of electrolyte transport in Caco-2 cell monolayers by enteropathogenic Escherichia coli (EPEC) infection

Gut ◽

10.1136/gut.42.2.200 ◽

1998 ◽

Vol 42 (2) ◽

pp. 200-207 ◽

Cited By ~ 64

Author(s):

G K Collington ◽

I W Booth ◽

S Knutton

Keyword(s):

Escherichia Coli ◽

Signal Transduction ◽

Short Circuit ◽

Electrolyte Transport ◽

Host Cells ◽

Ussing Chambers ◽

Cell Monolayers ◽

Initial Adhesion ◽

Rapid Modulation

Background and aims—The pathophysiology of enteropathogenic Escherichia coli (EPEC) diarrhoea remains uncertain. EPEC adhere to enterocytes and transduce signals which produce a characteristic “attaching and effacing” (A/E) lesion in the brush border membrane. The present in vitro study was designed to determine whether signal transduction by EPEC also influences electrolyte transport.Methods—Caco-2 cell monolayers were rapidly infected with wild type EPEC strain E2348/69, or the signal transduction-defective mutant 14.2.1(1), and mounted in Ussing chambers.Results—Strain E2348/69 stimulated a rapid but transient increase in short circuit current (Isc) which coincided with A/E lesion formation; this Isc response was absent on infection with strain 14.2.1(1). While the initial rise inIsc induced by E2348/69 was partially (∼35%) dependent on chloride, the remainder possibly represents an influx of sodium and amino acid(s) across the apical membrane.Conclusions—The study directly shows that, after initial adhesion, EPEC induce major alterations in host cell electrolyte transport. The observed Isc responses indicate a rapid modulation of electrolyte transport in Caco-2 cells by EPEC, including stimulation of chloride secretion, for which signal transduction to host cells is a prerequisite.

Download Full-text