Blastocystis ratti Contains Cysteine Proteases That Mediate Interleukin-8 Response from Human Intestinal Epithelial Cells in an NF-κB-Dependent Manner

ABSTRACT Blastocystis is a ubiquitous enteric protozoan found in the intestinal tracts of humans and a wide range of animals. Evidence accumulated over the last decade suggests association of Blastocystis with gastrointestinal disorders involving diarrhea, abdominal pain, constipation, nausea, and fatigue. Clinical and experimental studies have associated Blastocystis with intestinal inflammation, and it has been shown that Blastocystis has potential to modulate the host immune response. Blastocystis is also reported to be an opportunistic pathogen in immunosuppressed patients, especially those suffering from AIDS. However, nothing is known about the parasitic virulence factors and early events following host-parasite interactions. In the present study, we investigated the molecular mechanism by which Blastocystis activates interleukin-8 (IL-8) gene expression in human colonic epithelial T84 cells. We demonstrate for the first time that cysteine proteases of Blastocystis ratti WR1, a zoonotic isolate, can activate IL-8 gene expression in human colonic epithelial cells. Furthermore, we show that NF-κB activation is involved in the production of IL-8. In addition, our findings show that treatment with the antiprotozoal drug metronidazole can avert IL-8 production induced by B. ratti WR1. We also show for the first time that the central vacuole of Blastocystis may function as a reservoir for cysteine proteases. Our findings will contribute to an understanding of the pathobiology of a poorly studied parasite whose public health importance is increasingly recognized.

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Mechanism of dexamethasone-mediated interleukin-8 gene suppression in cultured airway epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.2001.280.1.l107 ◽

2001 ◽

Vol 280 (1) ◽

pp. L107-L115 ◽

Cited By ~ 36

Author(s):

Mary Mann-Jong Chang ◽

Maya Juarez ◽

Dallas M. Hyde ◽

Reen Wu

Keyword(s):

Gene Expression ◽

Protein Synthesis ◽

Epithelial Cells ◽

Actinomycin D ◽

Airway Epithelial Cells ◽

Interleukin 8 ◽

Transcriptional Level ◽

Dependent Manner ◽

Airway Epithelial ◽

New Protein

The effects of dexamethasone, a glucocorticoid analog, on interleukin 8 (IL-8) gene expression were studied in cultures of primary human tracheobronchial epithelial cells and an immortalized human bronchial epithelial cell line, HBE1 cells. Dexamethasone inhibited IL-8 mRNA and protein expression in a concentration- and time-dependent manner. The inhibition did not occur at the transcriptional level since both nuclear run-on activity and IL-8 promoter-reporter gene expression assay revealed no significant effect. Instead, there was a change in IL-8 mRNA stability in dexamethasone-treated cultures. Under actinomycin D treatment, IL-8 mRNA was quite stable in dexamethasone-depleted cultures, while in dexamethasone-pretreated cultures, IL-8 message was rapidly degraded within the first hour, then leveled off. When dexamethasone and actinomycin D were added simultaneously to dexamethasone-depleted cultures, IL-8 mRNA remained rather stable. When cycloheximide was used to inhibit new protein synthesis, dexamethasone-dependent inhibition was not observed. These results suggest that a posttranscriptional mechanism, which requires dexamethasone-dependent new protein synthesis, is involved in the regulation of IL-8 mRNA by dexamethasone in airway epithelial cells.

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Interleukin-8 gene expression in human bronchial epithelial cells.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)55037-7 ◽

1991 ◽

Vol 266 (29) ◽

pp. 19611-19617

Author(s):

H. Nakamura ◽

K. Yoshimura ◽

H.A. Jaffe ◽

R.G. Crystal

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Bronchial Epithelial Cells ◽

Interleukin 8 ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial

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Tenascin-C inhibits extracellular matrix-dependent gene expression in mammary epithelial cells. Localization of active regions using recombinant tenascin fragments

Journal of Cell Science ◽

10.1242/jcs.108.2.519 ◽

1995 ◽

Vol 108 (2) ◽

pp. 519-527 ◽

Cited By ~ 6

Author(s):

P.L. Jones ◽

N. Boudreau ◽

C.A. Myers ◽

H.P. Erickson ◽

M.J. Bissell

Keyword(s):

Gene Expression ◽

Extracellular Matrix ◽

Protein Synthesis ◽

Epithelial Cells ◽

Mammary Epithelial Cells ◽

Active Regions ◽

Mammary Epithelial ◽

Dependent Manner ◽

Beta Casein ◽

Casein Protein

The physiological role of tenascin in vivo has remained obscure. Although tenascin is regulated in a stage and tissue-dependent manner, knock-out mice appear normal. When tenascin expression was examined in the normal adult mouse mammary gland, little or none was present during lactation, when epithelial cells actively synthesize and secrete milk proteins in an extracellular matrix/lactogenic hormone-dependent manner. In contrast, tenascin was prominently expressed during involution, a stage characterized by the degradation of the extracellular matrix and the subsequent loss of milk production. Studies with mammary cell lines indicated that tenascin expression was high on plastic, but was suppressed in the presence of the laminin-rich, Engelbreth-Holm-Swarm (EHS) tumour biomatrix. When exogenous tenascin was added together with EHS to mammary epithelial cells, beta-casein protein synthesis and steady-state mRNA levels were inhibited in a concentration-dependent manner. Moreover, this inhibition by tenascin could be segregated from its effects on cell morphology. Using two beta-casein promoter constructs attached to the chloramphenicol acetyltransferase reporter gene we showed that tenascin selectively suppressed extracellular matrix/prolactin-dependent transcription of the beta-casein gene in three-dimensional cultures. Finally, we mapped the active regions within the fibronectin type III repeat region of the tenascin molecule that are capable of inhibiting beta-casein protein synthesis. Our data are consistent with a model where both the loss of a laminin-rich basement membrane by extracellular matrix-degrading enzymes and the induction of tenascin contribute to the loss of tissue-specific gene expression and thus the involuting process.

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Comparison of gene expression and activation of transcription factors in organoid-derived monolayer intestinal epithelial cells and organoids

Bioscience Biotechnology and Biochemistry ◽

10.1093/bbb/zbab136 ◽

2021 ◽

Author(s):

Yu Takahashi ◽

Yu Inoue ◽

Keitaro Kuze ◽

Shintaro Sato ◽

Makoto Shimizu ◽

...

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Gene Expression Regulation ◽

Intestinal Epithelial Cells ◽

Three Dimensional ◽

Culture Conditions ◽

Dependent Manner ◽

Intestinal Epithelial

Abstract Intestinal organoids better represent in vivo intestinal properties than conventionally used established cell lines in vitro. However, they are maintained in three-dimensional culture conditions that may be accompanied by handling complexities. We characterized the properties of human organoid-derived two-dimensionally cultured intestinal epithelial cells (IECs) compared with those of their parental organoids. We found that the expression of several intestinal markers and functional genes were indistinguishable between monolayer IECs and organoids. We further confirmed that their specific ligands equally activate intestinal ligand-activated transcriptional regulators in a dose-dependent manner. The results suggest that culture conditions do not significantly influence the fundamental properties of monolayer IECs originating from organoids, at least from the perspective of gene expression regulation. This will enable their use as novel biological tools to investigate the physiological functions of the human intestine.

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MEK Is a Key Modulator for TLR5-induced Interleukin-8 and MIP3α Gene Expression in Non-transformed Human Colonic Epithelial Cells

Journal of Biological Chemistry ◽

10.1074/jbc.m400967200 ◽

2004 ◽

Vol 279 (24) ◽

pp. 25179-25188 ◽

Cited By ~ 64

Author(s):

Sang Hoon Rhee ◽

Andrew C. Keates ◽

Mary P. Moyer ◽

Charalabos Pothoulakis

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Interleukin 8 ◽

Colonic Epithelial Cells

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Exploiting variability of single cells to uncover the in vivo hierarchy of miRNA targets

10.1101/035097 ◽

2015 ◽

Cited By ~ 2

Author(s):

Andrzej Jerzy Rzepiela ◽

Arnau Vina-Vilaseca ◽

Jeremie Breda ◽

Souvik Ghosh ◽

Afzal P Syed ◽

...

Keyword(s):

Gene Expression ◽

Single Cell ◽

Single Cells ◽

Human Embryonic Kidney Cells ◽

Mirna Targets ◽

Wide Range ◽

Gene Expression Dynamics ◽

Cell To Cell Variability ◽

First Time

MiRNAs are post-transcriptional repressors of gene expression that may additionally reduce the cell-to-cell variability in protein expression, induce correlations between target expression levels and provide a layer through which targets can influence each other's expression as 'competing RNAs' (ceRNAs). Here we combined single cell sequencing of human embryonic kidney cells in which the expression of two distinct miRNAs was induced over a wide range, with mathematical modeling, to estimate Michaelis-Menten (KM)-type constants for hundreds of evolutionarily conserved miRNA targets. These parameters, which we inferred here for the first time in the context of the entire network of endogenous miRNA targets, vary over ~2 orders of magnitude. They reveal an in vivo hierarchy of miRNA targets, defined by the concentration of miRNA-Argonaute complexes at which the targets are most sensitively down-regulated. The data further reveals miRNA-induced correlations in target expression at the single cell level, as well as the response of target noise to the miRNA concentration. The approach is generalizable to other miRNAs and post-transcriptional regulators and provides a deeper understanding of gene expression dynamics.

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The influence of elastin degradation products, glucose and atorvastatin on metalloproteinase-1, -2, -9 and tissue inhibitor of metalloproteinases-1, -2, -3 expression in human retinal pigment epithelial cells.

Acta Biochimica Polonica ◽

10.18388/abp.2014_1894 ◽

2014 ◽

Vol 61 (2) ◽

Cited By ~ 8

Author(s):

Mariola Dorecka ◽

Tomasz Francuz ◽

Wojciech Garczorz ◽

Krzysztof Siemianowicz ◽

Wanda Romaniuk

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Retinal Pigment Epithelial ◽

Degradation Products ◽

Retinal Pigment ◽

Retinal Pigment Epithelial Cells ◽

Dependent Manner ◽

Pigment Epithelial ◽

Elastin Degradation ◽

Pigment Epithelial Cells

Hyperglycemia and increased concentrations of elastin degradation products (EDPs) are common findings in patients with diabetes, atherosclerosis and hypertension. The aim of this study was to assess the influence of high glucose, EDPs and atorvastatin on MMP-1, MMP-2, MMP-9 and TIMP1-3 gene expression in human retinal pigment epithelial cells (HRPE) in vitro. HRPE were cultured for 24 hours with the substances being tested (glucose, EDPs), alone or in combination. Additionally, the cells were treated with atorvastatin in two different concentrations (1 or 10 μM). After incubation, total cellular RNA was extracted and used for gene expression evaluation. Gene expression was measured using the real-time RT-PCR technique. Glucose, EDPs and atorvastatin had no impact on TIMP-1 and TIMP-3 expression. HRPE cells treated with glucose or EDPs with the addition of atorvastatin had a statistically significant decrease of TIMP-2 expression; glucose alone decreased MMP-1 expression. Atorvastatin decreased expression of all assessed genes, except TIMP-1 and TIMP-3 in a dose-dependent manner. Our results confirm the importance of MMPs and TIMPs in retinal vascular biology. Atorvastatin-induced MMPs gene expression can deeply affect extracellular matrix turnover, which may play an important role in the progression of ocular diseases.

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A structural perspective on the mechanisms of quorum sensing activation in bacteria

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201520140482 ◽

2015 ◽

Vol 87 (4) ◽

pp. 2189-2203 ◽

Cited By ~ 5

Author(s):

CAROLINA LIXA ◽

AMANDA MUJO ◽

CRISTIANE D. ANOBOM ◽

ANDERSON S. PINHEIRO

Keyword(s):

Gene Expression ◽

Quorum Sensing ◽

Rational Design ◽

Three Dimensional ◽

Cell Communication ◽

Dependent Manner ◽

Regulate Gene Expression ◽

Wide Range ◽

A Cell ◽

Regulate Gene

Bacteria are able to synchronize the population behavior in order to regulate gene expression through a cell-to-cell communication mechanism called quorum sensing. This phenomenon involves the production, detection and the response to extracellular signaling molecules named autoinducers, which directly or indirectly regulate gene expression in a cell density-dependent manner. Quorum sensing may control a wide range of biological processes in bacteria, such as bioluminescence, virulence factor production, biofilm formation and antibiotic resistance. The autoinducers are recognized by specific receptors that can either be membrane-bound histidine kinase receptors, which work by activating cognate cytoplasmic response regulators, or cytoplasmic receptors acting as transcription factors. In this review, we focused on the cytosolic quorum sensing regulators whose three-dimensional structures helped elucidate their mechanisms of action. Structural studies of quorum sensing receptors may enable the rational design of inhibitor molecules. Ultimately, this approach may represent an effective alternative to treat infections where classical antimicrobial therapy fails to overcome the microorganism virulence.

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Interleukin-8 stimulates the migration of human colonic epithelial cells in vitro

Clinical Science ◽

10.1042/cs0970385 ◽

1999 ◽

Vol 97 (3) ◽

pp. 385-390 ◽

Cited By ~ 29

Author(s):

Andrew J. WILSON ◽

Keith BYRON ◽

Peter R. GIBSON

Keyword(s):

Cell Migration ◽

Epithelial Cells ◽

In Vitro Model ◽

Interleukin 8 ◽

Colonic Epithelium ◽

Dependent Manner ◽

Colonic Epithelial Cells ◽

Tnf Α ◽

Vitro Model

The migration of colonic epithelial cells (restitution) is an important event in the repair of mucosal injuries. Interleukin-8 (IL-8) is a physiological initiator of the chemotactic migration of leucocytes. This study aimed to determine whether IL-8 had a similar effect on migration in an in vitro model of wounded colonic epithelium. Cell migration over 24 h was assessed in circular wounds made in confluent monolayers of the human colon cancer cell line LIM1215. This migration was stimulated in a concentration-dependent manner by IL-8, with maximal effects of approx. 1.75-fold above basal migration. The motogenic effect of IL-8 was mediated independently of effects on cell proliferation. In contrast, it was partially dependent upon gene transcription and protein synthesis and involved the activation of pertussis-toxin-sensitive G-proteins. The short-chain fatty acids, acetate, propionate, butyrate and valerate, the activator of protein kinase C (phorbol-12-myristate-13-acetate) and tumour necrosis factor-α (TNF-α) all stimulated the secretion of IL-8. However, only the motogenic effect of TNF-α was dependent upon IL-8. In conclusion, IL-8 stimulated cell migration in an in vitro model of colonic epithelium, whereas the motogenic effect of at least one physiologically relevant factor was dependent upon an increase in its endogenous levels. If IL-8 stimulates colonic epithelial restitution in vivo, this would have ramifications for the control of repair processes following wounding of the colonic mucosa.

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