NF-kappa-B activation unveils the presence of inflammatory hotspots in human gut xenografts

ABSTRACTThe single-epithelial cell layer of the gut mucosa serves as an essential barrier between the host and luminal microflora and plays a major role in innate immunity against invading pathogens. Nuclear factor kB (NF-κB), a central component of the cellular signaling machinery, regulates immune response and inflammation. NF-κB proteins are activated by signaling pathways downstream to microbial recognition receptors and cytokines receptors. Highly regulated NF-κB activity in intestinal epithelial cells (IEC) is essential for normal gut homeostasis; dysregulated activity has been linked to a number of disease states, including inflammatory bowel diseases (IBD) such as Crohn’s Disease (CD). Our aim was to visualize and quantify spatial and temporal dynamics of NF-κB activity in steady state and inflamed human gut. Lentivirus technology was used to transduce the IEC of human gut xenografts in SCID mice with a NF-κB luminescence reporter system. NF-κB signaling was visualized and quantified using low resolution, intravital imaging of the whole body and high resolution, immunofluorescence microscopic imaging of the tissues. We show that NF-κB is activated in select subset of IEC with low “leaky” NF-κB activity. These unique inflammatory epithelial cells are clustered in the gut into discrete hotspots of NF-κB activity that are visible in steady state and selectively activated by systemic LPS and human TNFα or luminal bacteria. The presence of inflammatory hotspots in the normal and inflamed gut might explain the patchy mucosal lesions characterizing CD and thus could have important implications for diagnosis and therapy.

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NF-kappa-B activation unveils the presence of inflammatory hotspots in human gut xenografts

PLoS ONE ◽

10.1371/journal.pone.0243010 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0243010

Author(s):

Einat Nissim-Eliraz ◽

Eilam Nir ◽

Noga Marsiano ◽

Simcha Yagel ◽

Nahum Y. Shpigel

Keyword(s):

Steady State ◽

Epithelial Cells ◽

Temporal Dynamics ◽

Whole Body ◽

Central Component ◽

Reporter System ◽

Human Gut ◽

Nf Kappa B ◽

Bowel Diseases ◽

Epithelial Cell Layer

The single-epithelial cell layer of the gut mucosa serves as an essential barrier between the host and luminal microflora and plays a major role in innate immunity against invading pathogens. Nuclear factor kB (NF-κB), a central component of the cellular signaling machinery, regulates immune response and inflammation. NF-κB proteins are activated by signaling pathways downstream to microbial recognition receptors and cytokines receptors. Highly regulated NF-κB activity in intestinal epithelial cells (IEC) is essential for normal gut homeostasis; dysregulated activity has been linked to a number of disease states, including inflammatory bowel diseases (IBD) such as Crohn’s Disease (CD). Our aim was to visualize and quantify spatial and temporal dynamics of NF-κB activity in steady state and inflamed human gut. Lentivirus technology was used to transduce the IEC of human gut xenografts in SCID mice with a NF-κB luminescence reporter system. NF-κB signaling was visualized and quantified using low resolution, intravital imaging of the whole body and high resolution, immunofluorescence microscopic imaging of the tissues. We show that NF-κB is activated in select subset of IEC with low “leaky” NF-κB activity. These unique inflammatory epithelial cells are clustered in the gut into discrete hotspots of NF-κB activity that are visible in steady state and selectively activated by systemic LPS and human TNFα or luminal bacteria. The presence of inflammatory hotspots in the normal and inflamed gut might explain the patchy mucosal lesions characterizing CD and thus could have important implications for diagnosis and therapy.

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Continuous Estimation of CO2 Production during Exercise

Methods of Information in Medicine ◽

10.1055/s-0038-1636856 ◽

1997 ◽

Vol 36 (04/05) ◽

pp. 368-371

Author(s):

R. Soma ◽

Y. Yamamoto

Keyword(s):

Fuzzy Logic ◽

Steady State ◽

Infusion Rate ◽

Feedback System ◽

Whole Body ◽

Co2 Production ◽

Cycle Exercise ◽

Continuous Estimation ◽

Breath Measurement ◽

13Co2 Enrichment

Abstract.A new method was developed for continuous isotopic estimation of human whole body CO2 rate of appearance (Ra) during non-steady state exercise. The technique consisted of a breath-by-breath measurement of 13CO2 enrichment (E) and a real-time fuzzy logic feedback system which controlled NaH13CO3 infusion rate to achieve an isotopic steady state. Ra was estimated from the isotope infusion rate and body 13CO2 enrichment which was equal to E at the isotopic steady state. During a non-steady state incremental cycle exercise (5 w/min or 10 w/min), NaH13CO3 infusion rate was successfully increased by the action of feedback controller so as to keep E constant.

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Gut Mycobiota and Fungal Metabolites in Human Homeostasis

Current Drug Targets ◽

10.2174/1389450119666180724125020 ◽

2018 ◽

Vol 20 (2) ◽

pp. 232-240 ◽

Cited By ~ 3

Author(s):

Izabella Mogilnicka ◽

Marcin Ufnal

Keyword(s):

Wide Spectrum ◽

Biological Effects ◽

Fungal Species ◽

Fungal Metabolites ◽

Human Gut ◽

Fecal Transplantation ◽

Bacterial Microbiota ◽

Bowel Diseases ◽

Inflammatory Bowel

Background:Accumulating evidence suggests that microbiota play an important role in host’s homeostasis. Thus far, researchers have mostly focused on the role of bacterial microbiota. However, human gut is a habitat for several fungal species, which produce numerous metabolites. Furthermore, various types of food and beverages are rich in a wide spectrum of fungi and their metabolites.Methods:We searched PUBMED and Google Scholar databases to identify clinical and pre-clinical studies on fungal metabolites, composition of human mycobiota and fungal dysbiosis.Results:Fungal metabolites may serve as signaling molecules and exert significant biological effects including trophic, anti-inflammatory or antibacterial actions. Finally, research suggests an association between shifts in gut fungi composition and human health. Changes in mycobiota composition have been found in obesity, hepatitis and inflammatory bowel diseases.Conclusion:The influence of mycobiota and dietary fungi on homeostasis in mammals suggests a pharmacotherapeutic potential of modulating the mycobiota which may include treatment with probiotics and fecal transplantation. Furthermore, antibacterial action of fungi-derived molecules may be considered as a substitution for currently used antibacterial agents and preservatives in food industry.

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Cyclic Breathing Simulations in Large Scale Models of the Lung Airway From the Oronasal Opening to the Terminal Bronchioles

Volume 2: Biomedical and Biotechnology ◽

10.1115/imece2012-88901 ◽

2012 ◽

Author(s):

D. Keith Walters ◽

Greg W. Burgreen ◽

Robert L. Hester ◽

David S. Thompson ◽

David M. Lavallee ◽

...

Keyword(s):

Steady State ◽

Boundary Conditions ◽

Large Scale ◽

Whole Body ◽

Patient Specific ◽

Cfd Simulations ◽

Reduced Order ◽

Scale Models ◽

Steady State Simulation ◽

Conducting Zone

Computational fluid dynamics (CFD) simulations were performed for unsteady periodic breathing conditions, using large-scale models of the human lung airway. The computational domain included fully coupled representations of the orotracheal region and large conducting zone up to generation four (G4) obtained from patient-specific CT data, and the small conducting zone (to G16) obtained from a stochastically generated airway tree with statistically realistic geometrical characteristics. A reduced-order geometry was used, in which several airway branches in each generation were truncated, and only select flow paths were retained to G16. The inlet and outlet flow boundaries corresponded to the oronasal opening (superior), the inlet/outlet planes in terminal bronchioles (distal), and the unresolved airway boundaries arising from the truncation procedure (intermediate). The cyclic flow was specified according to the predicted ventilation patterns for a healthy adult male at three different activity levels, supplied by the whole-body modeling software HumMod. The CFD simulations were performed using Ansys FLUENT. The mass flow distribution at the distal boundaries was prescribed using a previously documented methodology, in which the percentage of the total flow for each boundary was first determined from a steady-state simulation with an applied flow rate equal to the average during the inhalation phase of the breathing cycle. The distal pressure boundary conditions for the steady-state simulation were set using a stochastic coupling procedure to ensure physiologically realistic flow conditions. The results show that: 1) physiologically realistic flow is obtained in the model, in terms of cyclic mass conservation and approximately uniform pressure distribution in the distal airways; 2) the predicted alveolar pressure is in good agreement with previously documented values; and 3) the use of reduced-order geometry modeling allows accurate and efficient simulation of large-scale breathing lung flow, provided care is taken to use a physiologically realistic geometry and to properly address the unsteady boundary conditions.

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Proteomic response of inflammatory stimulated intestinal epithelial cells to in vitro digested plums and cabbages rich in carotenoids and polyphenols

Food & Function ◽

10.1039/c6fo00674d ◽

2016 ◽

Vol 7 (10) ◽

pp. 4388-4399 ◽

Cited By ~ 4

Author(s):

Anouk Kaulmann ◽

Sébastien Planchon ◽

Jenny Renaut ◽

Yves-Jacques Schneider ◽

Lucien Hoffmann ◽

...

Keyword(s):

Epithelial Cells ◽

Inflammatory Bowel Diseases ◽

Intestinal Epithelial Cells ◽

Intestinal Cells ◽

Intestinal Epithelial ◽

Bowel Diseases ◽

Inflammatory Bowel ◽

Proteomic Response

Proteomic response of intestinal cells as a model of inflammatory bowel diseases to digested plum and cabbage rich in polyphenols and carotenoids.

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Vitamin D/VDR signaling inhibits colitis by suppressing HIF-1α activation in colonic epithelial cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00061.2021 ◽

2021 ◽

Author(s):

Gang Xue ◽

Ruifang Gao ◽

Zhuanzhuan Liu ◽

Na Xu ◽

Yong Cao ◽

...

Keyword(s):

Vitamin D ◽

Animal Models ◽

Epithelial Cells ◽

Dextran Sulfate ◽

Hypoxia Inducible Factor ◽

Dependent Manner ◽

Trinitrobenzenesulfonic Acid ◽

Colonic Epithelial Cells ◽

Bowel Diseases ◽

Inflammatory Bowel

Vitamin D/vitamin D receptor (VDR) signaling is reported to have a protective effect on the onset or progression of inflammatory bowel diseases (IBD) and hypoxia-inducible factor 1α (HIF-1α) activation is demonstrated to be closely associated with chemical-induced colitis. However, the association between vitamin D/VDR signaling and HIF-1α on IBD development remains a mystery. Here, we showed that HIF-1α expression was largely increased in the colonic epithelial cells of diseased tissues from ulcerative colitis (UC) patients. Consistently, HIF-1α activation was also improved in colonic epithelial cells upon TNFα treatment in a NF-κB pathway-dependent manner. HIF-1α inhibitors treatments ameliorated 2,4,6-trinitrobenzenesulfonic acid (TNBS)- or dextran sulfate sodium (DSS)-induced colitis in animal models. In cell or colitis animal models, vitamin D/VDR signaling suppressed HIF-1α overexpression in colonic epithelial cells via regulating NF-κB pathway, resulting in the inhibition of IFNγ and IL-1β overproductions in these cells. Collectively, these data suggest that vitamin D/VDR signaling relieves colitis development in animal models, at least in part, by suppressing HIF-1α expression in colonic epithelial cells.

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Regulatory mechanism of ulinastatin on autophagy of macrophages and renal tubular epithelial cells

Open Chemistry ◽

10.1515/chem-2018-0025 ◽

2018 ◽

Vol 16 (1) ◽

pp. 298-305

Author(s):

Ming Wu ◽

Min Hu ◽

Huansheng Tong ◽

Junying Liu ◽

Hui Jiang ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Epithelial Cells ◽

Renal Cell ◽

Reactive Oxygen ◽

Whole Body ◽

Inflammatory Factors ◽

Oxygen Species ◽

Tubular Epithelial Cells ◽

Renal Tubular Epithelial Cells ◽

Renal Tubular

AbstractKidney ischemia and hypoxia can cause renal cell apoptosis and activation of inflammatory cells, which lead to the release of inflammatory factors and ultimately result in the damage of kidney tissue and the whole body. Renal tubular cell and macrophage autophagy can reduce the production of reactive oxygen species (ROS), thereby reducing the activation of inflammatory cytoplasm and its key effector protein, caspase-1, which reduces the expression of IL-1β and IL-18 and other inflammatory factors. Ulinastatin (UTI), as a glycoprotein drug, inhibits the activity of multiple proteases and reduces myocardial damage caused by ischemia-reperfusion by upregulating autophagy. However, it can be raised by macrophage autophagy, reduce the production of ROS, and ultimately reduce the expression of inflammatory mediators, thereby reducing renal cell injury, promote renal function recovery is not clear. In this study, a series of cell experiments have shown that ulinastatin is reduced by regulating the autophagy of renal tubular epithelial cells and macrophages to reduce the production of reactive oxygen species and inflammatory factors (TNF-α, IL-1β and IL-1), and then, increase the activity of the cells under the sugar oxygen deprivation model. The simultaneous use of cellular autophagy agonists Rapamycin (RAPA) and ulinastatin has a synergistic effect on the production of reactive oxygen species and the expression of inflammatory factors.

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Levitation of non-magnetizable droplet inside ferrofluid

Journal of Fluid Mechanics ◽

10.1017/jfm.2018.733 ◽

2018 ◽

Vol 857 ◽

pp. 398-448 ◽

Cited By ~ 1

Author(s):

Chamkor Singh ◽

Arup K. Das ◽

Prasanta K. Das

Keyword(s):

Magnetic Field ◽

Steady State ◽

Viscosity Ratio ◽

Temporal Dynamics ◽

Liquid Droplet ◽

Droplet Surface ◽

Two Dimensions ◽

Projection Algorithm ◽

The Stability ◽

The Individual

The central theme of this work is that a stable levitation of a denser non-magnetizable liquid droplet, against gravity, inside a relatively lighter ferrofluid – a system barely considered in ferrohydrodynamics – is possible, and exhibits unique interfacial features; the stability of the levitation trajectory, however, is subject to an appropriate magnetic field modulation. We explore the shapes and the temporal dynamics of a plane non-magnetizable droplet levitating inside a ferrofluid against gravity due to a spatially complex, but systematically generated, magnetic field in two dimensions. The coupled set of Maxwell’s magnetostatic equations and the flow dynamic equations is integrated computationally, utilizing a conservative finite-volume-based second-order pressure projection algorithm combined with the front-tracking algorithm for the advection of the interface of the droplet. The dynamics of the droplet is studied under both the constant ferrofluid magnetic permeability assumption as well as for more realistic field-dependent permeability described by Langevin’s nonlinear magnetization model. Due to the non-homogeneous nature of the magnetic field, unique shapes of the droplet during its levitation, and at its steady state, are realized. The complete spatio-temporal response of the droplet is a function of the Laplace number $La$ , the magnetic Laplace number $La_{m}$ and the Galilei number $Ga$ ; through detailed simulations we separate out the individual roles played by these non-dimensional parameters. The effect of the viscosity ratio, the stability of the levitation path and the possibility of existence of multiple stable equilibrium states is investigated. We find, for certain conditions on the viscosity ratio, that there can be developments of cusps and singularities at the droplet surface; we also observe this phenomenon experimentally and compare with the simulations. Our simulations closely replicate the singular projection on the surface of the levitating droplet. Finally, we present a dynamical model for the vertical trajectory of the droplet. This model reveals a condition for the onset of levitation and the relation for the equilibrium levitation height. The linearization of the model around the steady state captures that the nature of the equilibrium point goes under a transition from being a spiral to a node depending upon the control parameters, which essentially means that the temporal route to the equilibrium can be either monotonic or undulating. The analytical model for the droplet trajectory is in close agreement with the detailed simulations.

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Transgenic overexpression of β2-adrenergic receptors in airway epithelial cells decreases bronchoconstriction

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.2000.279.2.l379 ◽

2000 ◽

Vol 279 (2) ◽

pp. L379-L389 ◽

Cited By ~ 24

Author(s):

Dennis W. McGraw ◽

Susan L. Forbes ◽

Judith C. W. Mak ◽

David P. Witte ◽

Patricia E. Carrigan ◽

...

Keyword(s):

Epithelial Cells ◽

Airway Epithelium ◽

Adrenergic Receptors ◽

Airway Epithelial Cells ◽

Airway Responsiveness ◽

Ozone Exposure ◽

Clara Cell ◽

Whole Body ◽

Airway Epithelial

Airway epithelial cells express β2-adrenergic receptors (β2-ARs), but their role in regulating airway responsiveness is unclear. With the Clara cell secretory protein (CCSP) promoter, we targeted expression of β2-ARs to airway epithelium of transgenic (CCSP-β2-AR) mice, thereby mimicking agonist activation of receptors only in these cells. In situ hybridization confirmed that transgene expression was confined to airway epithelium, and autoradiography showed that β2-AR density in CCSP-β2-AR mice was approximately twofold that of nontransgenic (NTG) mice. Airway responsiveness measured by whole body plethysmography showed that the methacholine dose required to increase enhanced pause to 200% of baseline (ED200) was greater for CCSP-β2-AR than for NTG mice (345 ± 34 vs. 157 ± 14 mg/ml; P < 0.01). CCSP-β2-AR mice were also less responsive to ozone (0.75 ppm for 4 h) because enhanced pause in NTG mice acutely increased to 77% over baseline ( P < 0.05) but remained unchanged in the CCSP-β2-AR mice. Although both groups were hyperreactive to methacholine 6 h after ozone exposure, the ED200for ozone-exposed CCSP-β2-AR mice was equivalent to that for unexposed NTG mice. These findings show that epithelial cell β2-ARs regulate airway responsiveness in vivo and that the bronchodilating effect of β-agonists results from activation of receptors on both epithelial and smooth muscle cells.

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