scholarly journals 15-Deoxy-Δ12,14-prostaglandin J2-mediated ERK Signaling Inhibits Gram-negative Bacteria-induced RelA Phosphorylation and Interleukin-6 Gene Expression in Intestinal Epithelial Cells through Modulation of Protein Phosphatase 2A Activity

2004 ◽  
Vol 279 (34) ◽  
pp. 36103-36111 ◽  
Author(s):  
Pedro A. Ruiz ◽  
Sandra C. Kim ◽  
R. Balfour Sartor ◽  
Dirk Haller
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Interleukin 6 ◽  
Protein Phosphatase ◽  
Intestinal Epithelial Cells ◽  
Erk Signaling ◽  
Gram Negative Bacteria ◽  
Intestinal Epithelial ◽  
Gram Negative ◽  
Phosphatase 2A

Transcriptomic response of immune signalling pathways in intestinal epithelial cells exposed to lipopolysaccharides, Gram-negative bacteria or potentially probiotic microbes

2012 ◽  
Vol 3 (4) ◽  
pp. 273-286 ◽  
Author(s):  
J. Audy ◽  
O. Mathieu ◽  
J. Belvis ◽  
T.A. Tompkins
Keyword(s):  
Epithelial Cells ◽  
Host Response ◽  
Intestinal Epithelial Cells ◽  
Mitogen Activated Protein Kinase ◽  
Gram Negative Bacteria ◽  
Intestinal Epithelial ◽  
Gram Positive ◽  
Transcriptomic Response ◽  
Gram Negative ◽  
The Impact

In order to understand the appropriate use of potentially probiotic Gram-positive microbes through their introduction in the gut microbiome, it is necessary to understand the influence of individual bacteria on the host-response system at a cellular level. In the present study, we have shown that lipopolysaccharides, flagellated Gram-negative bacteria, potentially probiotic Gram-positive bacteria and yeast interact differently with human intestinal epithelial cells with a custom-designed expression microarray evaluating 17 specific host-response pathways. Only lipopolysaccharides and flagellated Gram-negative bacteria induced inflammatory response, while a subset of Gram-positive microbes had anti-inflammatory potential. The main outcome from the study was the differential regulation of the central mitogen-activated protein kinase signalling pathway by these Gram-positive microbes versus commensal/pathogenic Gram-negative bacteria. The microarray was efficient to highlight the impact of individual bacteria on the response of intestinal epithelial cells, but quantitative real-time polymerase chain reaction validation demonstrated some underestimation for down-regulated genes by the microarray. This immune array will allow us to better understand the mechanisms underlying microbe-induced host immune responses.

Induced TRPC1 expression increases protein phosphatase 2A sensitizing intestinal epithelial cells to apoptosis through inhibition of NF-κB activation

2008 ◽  
Vol 294 (5) ◽  
pp. C1277-C1287 ◽  
Author(s):  
Bernard S. Marasa ◽  
Lan Xiao ◽  
Jaladanki N. Rao ◽  
Tongtong Zou ◽  
Lan Liu ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Protein Phosphatase ◽  
Transient Receptor Potential ◽  
Intestinal Epithelial Cells ◽  
Protein Phosphatase 2A ◽  
Mrna Levels ◽  
Intestinal Epithelial ◽  
Pp2a Activity ◽  
Tnf Α ◽  
Phosphatase 2A

Transient receptor potential canonical-1 (TRPC1) functions as a store-operated Ca2+ channel in intestinal epithelial cells (IECs), and induced TRPC1 expression sensitizes IECs to apoptosis by inhibiting NF-κB activation. However, the exact mechanism by which increased TRPC1 results in NF-κB inactivation remains elusive. Protein phosphatase 2A (PP2A) is a widely conserved protein serine/threonine phosphatase that is implicated in the regulation of a wide array of cellular functions including apoptosis. The present study tests the hypothesis that induced TRPC1 expression inhibits NF-κB activation by increasing PP2A activity through Ca2+ influx in IECs. The expression of TRPC1 induced by stable transfection with the wild-type TRPC1 gene increased PP2A activity as indicated by increases in levels of PP2A proteins and their phosphatase activity. Increased levels of PP2A activity in stable TRPC1-transfected IEC-6 cells (IEC-TRPC1) were associated with decreased nuclear levels of NF-κB proteins and a reduction in NF-κB-dependent transcriptional activity, although there were no changes in total NF-κB protein levels. Inhibition of PP2A activity by treatment with okadaic acid or PP2A silencing with small interfering RNA not only enhanced NF-κB transactivation but also prevented the increased susceptibility of IEC-TRPC1 cells to apoptosis induced by treatment with tumor necrosis factor-α (TNF-α)/cycloheximide (CHX). Decreasing Ca2+ influx by exposure to the Ca2+-free medium reduced PP2A mRNA levels, destabilized PP2A proteins, and induced NF-κB activation, thus blocking the increased sensitivity of IEC-TRPC1 cells to TNF-α/CHX-induced apoptosis. These results indicate that induced TRPC1 expression increases PP2A activity through Ca2+ influx and that increased PP2A sensitizes IECs to apoptosis as a result of NF-κB inactivation.

scholarly journals Antibacterial activity of a synthetic peptide (PR-26) derived from PR-39, a proline-arginine-rich neutrophil antimicrobial peptide.

1996 ◽  
Vol 40 (1) ◽  
pp. 115-121 ◽  
Author(s):  
J Shi ◽  
C R Ross ◽  
M M Chengappa ◽  
M J Sylte ◽  
D S McVey ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Synthetic Peptide ◽  
Intestinal Epithelial Cells ◽  
Functional Domain ◽  
Gram Negative Bacteria ◽  
Intestinal Epithelial ◽  
Amino Acid Residues ◽  
Truncated Form ◽  
Gram Negative ◽  
Salmonella Choleraesuis

PR-39 is a proline-arginine-rich (PR) neutrophil antibacterial peptide originally identified and purified from the porcine small intestine. We report on the synthesis of a functional antibacterial domain of PR-39, the first 26 amino acid residues of the NH2 terminus. PR-26 was as potent as or more potent than PR-39 against enteric gram-negative bacteria. This truncated form of PR-39 potentiated neutrophil phagocytosis of Salmonella choleraesuis and decreased the level of S. typhimurium invasion into intestinal epithelial cells. Scanning electron microscopy confirmed that these peptides did not lyse cells by pore-forming mechanisms; however, they potentiated the antibacterial capabilities of a pore-forming peptide, magainin A. In addition, PR-26 was not toxic to epithelial cells at concentrations several times greater than its bactericidal concentration. These data suggest that PR-39 and its functional domain, PR-26, may potentiate the host's defense capabilities against gram-negative infections.

scholarly journals CDX2 regulates interleukin‐33 gene expression in intestinal epithelial cells (LS174T)

FEBS Open Bio ◽  
2021 ◽  
Author(s):  
Sylvester Larsen ◽  
Jakob Benedict Seidelin ◽  
Johanne Davidsen ◽  
Katja Dahlgaard ◽  
Claus Henrik Nielsen ◽  
...  
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Intestinal Epithelial ◽  
Interleukin 33

GENE EXPRESSION IN INTESTINAL EPITHELIAL CELLS, IEC-6, IS ALTERED BY BURN INJURY-INDUCED CIRCULATING FACTORS

Shock ◽  
2001 ◽  
Vol 16 (4) ◽  
pp. 259-263 ◽  
Author(s):  
Maryam Varedi ◽  
Heung-Man Lee ◽  
George H. Greeley ◽  
David N. Herndon ◽  
Ella W. Englander
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Burn Injury ◽  
Intestinal Epithelial Cells ◽  
Intestinal Epithelial
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