Bile salts-induced PGE2 release, PKCE and COX-2 expression, parallel the increased cellproliferation in an ex vivo model of Barrett's esophagus

Rates of esophageal cancer have increased over the last 40 years. Recent clinical research has identified correlations between the esophageal microbiome and disease. However, mechanisms of action have been difficult to elucidate performing human experimentation. We propose an ex vivo model, which mimics the esophagus and is ideal for mechanistic studies on the esophageal microbiome and resultant transcriptome. To determine the microbiome and transcriptome profile of the human distal esophagus, the microbiome was assessed in 74 patients and the transcriptome profile was assessed in 37 patients with and without Barrett’s esophagus. Thereafter, an ex vivo model of the esophagus was created using an air–liquid interfaced (ALI) design. This design created a sterile apical surface and a nutrient-rich basal surface. An epithelial layer was grown on the apical surface. A normal microbiome and Barrett’s microbiome was harvested and created from patients during endoscopic examination of the esophagus. There was a distinct microbiome in patients with Barrett’s esophagus. The ex vivo model was successfully created with a squamous epithelial layer on the apical surface of the ex vivo system. Using this ex vivo model, multiple normal esophageal and Barrett’s esophageal cell lines will be created and used for experimentation. Each microbiome will be inoculated onto the sterile apical surface of each cell line. The resultant microbiome and transcriptome profile on each surface will be measured and compared to results in the human esophagus to determine the mechanism of the microbiome interaction.

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Acid- and bile-induced PGE2release and hyperproliferation in Barrett's esophagus are COX-2 and PKC-ε dependent

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00543.2001 ◽

2002 ◽

Vol 283 (2) ◽

pp. G327-G334 ◽

Cited By ~ 48

Author(s):

Baljeet S. Kaur ◽

George Triadafilopoulos

Keyword(s):

Bile Salt ◽

Barrett’S Esophagus ◽

Barrett's Esophagus ◽

Bile Salts ◽

Bile Reflux ◽

Salt Mixture ◽

Dramatic Decrease ◽

Pkc Inhibitor ◽

Kinase C ◽

Cox 2

Barrett's esophagus (BE) results from acid and bile reflux and predisposes to cancer. To further understand the mechanisms of acid- and bile-induced hyperproliferation in BE, we investigated the release of PGE2in response to acid or bile salt exposure. Biopsies of esophagus, BE, and duodenum were exposed to a bile salt mixture as a 1-h pulse and compared with exposure to pH 7.4 for up to 24 h, and PGE2release, cyclooxygenase-2 (COX-2), and protein kinase C (PKC) expression were compared. Similar experiments were also performed with acidified media (pH 3.5) alone, in the presence or absence of bisindolylmaleimide (BIM), a selective PKC inhibitor, and NS-398, a COX-2 inhibitor. One-hour pulses of bile salts or acid significantly enhanced proliferation, COX-2 expression, and PGE2release in BE. In contrast, the combination pulse of acid and bile salts had no such effect. Treatment with either BIM or NS-398 led to a dramatic decrease in PGE2release in BE explants and a suppression of proliferation. The acid- or bile salt-mediated hyperproliferation is related to PGE2release. Acid- and bile salt-induced induction of COX-2 and PKC may explain, at least in part, the tumor-promoting effects of acid and bile in BE.

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Contribution of stromal and epithelial cells to cyclooxygenase-2 (COX-2) activity in Barrett's esophagus

Gastroenterology ◽

10.1016/s0016-5085(01)80387-5 ◽

2001 ◽

Vol 120 (5) ◽

pp. A78-A79

Author(s):

N BUTTAR ◽

K WANG ◽

M ANDERSON ◽

L LUTZKE ◽

K KRISHNADATH

Keyword(s):

Epithelial Cells ◽

Barrett’S Esophagus ◽

Barrett's Esophagus ◽

Cyclooxygenase 2 ◽

Cox 2

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Methylene Blue Staining of Dysplastic and Nondysplastic Barrett's Esophagus: An In Vivo and Ex Vivo Study

Endoscopy ◽

10.1055/s-2001-14427 ◽

2001 ◽

Vol 33 (5) ◽

pp. 391-400 ◽

Cited By ~ 103

Author(s):

M. I. Canto ◽

S. Setrakian ◽

J. E. Willis ◽

A. Chak ◽

R. E. Petras ◽

...

Keyword(s):

Methylene Blue ◽

Barrett’S Esophagus ◽

Barrett's Esophagus ◽

Ex Vivo ◽

Blue Staining ◽

Ex Vivo Study

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Bile salts induce or blunt cell proliferation in Barrett's esophagus in an acid-dependent fashion

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.2000.278.6.g1000 ◽

2000 ◽

Vol 278 (6) ◽

pp. G1000-G1009 ◽

Cited By ~ 55

Author(s):

Baljeet S. Kaur ◽

Rodica Ouatu-Lascar ◽

M. Bishr Omary ◽

George Triadafilopoulos

Keyword(s):

Cell Proliferation ◽

Bile Salt ◽

Barrett’S Esophagus ◽

Barrett's Esophagus ◽

Bile Salts ◽

Bile Reflux ◽

Salt Mixture ◽

Complete Obliteration ◽

Protein Kinase C Inhibitor ◽

Incorporation Assay

Barrett's esophagus (BE) results from acid and bile reflux and predisposes to cancer. We investigated the effect of bile salts, with or without acid, on cell proliferation in BE and assessed mechanism(s) involved. To mimic physiological conditions, biopsies of esophagus, BE, and duodenum were exposed to a bile salt mixture, either continuously or as a 1-h pulse, and were compared with control media without bile salts (pH 7.4) for ≤24 h. Similar experiments were also performed with acidified media (pH 3.5) combined with the bile salt mixture as a 1-h pulse. Cell proliferation was assessed by a [3H]thymidine incorporation assay with or without bisindolylmaleimide (BIM), a selective protein kinase C inhibitor. Bile salt pulses enhanced cell proliferation in BE without affecting cell proliferation in esophageal or duodenal epithelia. In the presence of BIM, there was complete obliteration of the bile salt-induced BE hyperproliferation. In contrast, 1-h pulses of bile salts in combination with acid significantly inhibited proliferation in BE but had no effect on esophagus or duodenum. We conclude that in BE explants, brief exposure to bile salts, in the absence of acid, increases proliferation, whereas exposure to a combination of bile salts and acid together inhibits proliferation.

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Detection of early neoplasia in Barrett’s esophagus using lectin-based near-infrared imaging: an ex vivo study on human tissue

Endoscopy ◽

10.1055/s-0043-124080 ◽

2018 ◽

Vol 50 (06) ◽

pp. 618-625 ◽

Cited By ~ 11

Author(s):

André Neves ◽

Massimiliano Di Pietro ◽

Maria O’Donovan ◽

Dale Waterhouse ◽

Sarah Bohndiek ◽

...

Keyword(s):

Barrett’S Esophagus ◽

Barrett's Esophagus ◽

Near Infrared ◽

Infrared Imaging ◽

Ex Vivo ◽

Sampling Error ◽

Nir Light ◽

Nir Imaging ◽

Nir Fluorescence ◽

Nir Dye

Abstract Background and study aims Endoscopic surveillance for Barrett’s esophagus (BE) is limited by long procedure times and sampling error. Near-infrared (NIR) fluorescence imaging minimizes tissue autofluorescence and optical scattering. We assessed the feasibility of a topically applied NIR dye-labeled lectin for the detection of early neoplasia in BE in an ex vivo setting. Methods Consecutive patients undergoing endoscopic mucosal resection (EMR) for BE-related early neoplasia were recruited. Freshly collected EMR specimens were sprayed at the bedside with fluorescent lectin and then imaged. Punch biopsies were collected from each EMR under NIR light guidance. We compared the fluorescence intensity from dysplastic and nondysplastic areas within EMRs and from punch biopsies with different histological grades. Results 29 EMR specimens were included from 17 patients. A significantly lower fluorescence was found for dysplastic regions across whole EMR specimens (P < 0.001). We found a 41 % reduction in the fluorescence of dysplastic compared to nondysplastic punch biopsies (P < 0.001), with a sensitivity and specificity for dysplasia detection of 80 % and 82.9 %, respectively. Conclusion Lectin-based NIR imaging can differentiate dysplastic from nondysplastic Barrett’s mucosa ex vivo.

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Protective Effects Induced by Two Polyphenolic Liquid Complexes from Olive (Olea europaea, mainly Cultivar Coratina) Pressing Juice in Rat Isolated Tissues Challenged with LPS

Molecules ◽

10.3390/molecules24163002 ◽

2019 ◽

Vol 24 (16) ◽

pp. 3002 ◽

Cited By ~ 3

Author(s):

Lucia Recinella ◽

Annalisa Chiavaroli ◽

Giustino Orlando ◽

Luigi Menghini ◽

Claudio Ferrante ◽

...

Keyword(s):

Prefrontal Cortex ◽

Ex Vivo ◽

Protective Role ◽

Rat Colon ◽

Inos Mrna ◽

Mrna Levels ◽

Protective Effects ◽

Ex Vivo Model ◽

Cox 2 ◽

Factor Α

MOMAST(®) HY100 and MOMAST(®) HP30 are polyphenolic liquid complexes from olive pressing juice with a total polyphenolic content of 100 g/kg (at least 50% as hydroxytyrosol) and 36 g/kg (at least 30% as hydroxytyrosol), respectively. We investigated the potential protective role of MOMAST(®) HY100 and MOMAST(®) HP30 on isolated rat colon, liver, heart, and prefrontal cortex specimens treated with Escherichia coli lipopolysaccharide (LPS), a validated ex vivo model of inflammation, by measuring the production of prostaglandin (PG)E2, 8-iso-PGF2α, lactate dehydrogenase (LDH), as well as cyclooxygenase (COX)-2, tumor necrosis factor α (TNFα), and inducible nitric oxide synthase (iNOS) mRNA levels. MOMAST(®) HY100 decreased LPS-stimulated PGE2 and LDH levels in all tested tissues. Following treatment with MOMAST(®) HY100, we found a significant reduction in iNOS levels in prefrontal cortex and heart specimens, COX-2 and TNFα mRNA levels in heart specimens, and 8-iso-PGF2α levels in liver specimens. On the other hand, MOMAST(®) HP30 was found to blunt COX-2, TNFα, and iNOS mRNA levels, as well as 8-iso-PGF2α in cortex, liver, and colon specimens. MOMAST(®) HP30 was also found to decrease PGE2 levels in liver specimens, while it decreased iNOS mRNA, LDH, and 8-iso-PGF2α levels in heart specimens. Both MOMAST(®) HY100 and MOMAST(®) HP30 exhibited protective effects on multiple inflammatory and oxidative stress pathways.

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