Active or Autoclaved Akkermansia muciniphila Relieves TNF-α-Induced Inflammation in Intestinal Epithelial Cells Through Distinct Pathways

Intestinal inflammation is a major threat to the health and growth of young animals such as piglets. As a next-generation probiotics, limited studies have shown that Akkermansia muciniphila could alleviate inflammation of intestinal epithelial cells (IECs). In this study, a TNF-α-induced inflammatory model of IPEC-J2 cells, the intestinal porcine enterocytes, was built to evaluate the effects of active or inactive A. muciniphila on the inflammation of IECs. The viability of IPEC-J2 cells was the highest when treated with active (108 copies/mL) or inactive (109 copies/mL) A. muciniphila for 7.5 h (P < 0.01). Treated with 20 ng/mL of TNF-α and followed by a treatment of A. muciniphila, the mRNA level of proinflammatory cytokines (IL-8, IL-1β, IL-6 and TNF-α) was remarkably reduced (P < 0.05) along with the increased mRNA level of tight junction proteins (ZO-1 and Occludin, P < 0.05). Flow cytometry analysis showed that active or inactive A. muciniphila significantly suppressed the rate of the early and total apoptotic of the inflammatory IPEC-J2 cells (P < 0.05). According to results of transcriptome sequencing, active and inactive A. muciniphila may decline cell apoptosis by down-regulating the expression of key genes in calcium signaling pathway, or up-regulating the expression of key genes in cell cycle signaling pathway. And the bacterium may alleviate the inflammation of IECs by down-regulating the expression of PI3K upstream receptor genes. Our results indicate that A. muciniphila may be a promising NGP targeting intestinal inflammation.

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EZH2 Regulates Intestinal Inflammation and Necroptosis Through the JNK Signaling Pathway in Intestinal Epithelial Cells

Digestive Diseases and Sciences ◽

10.1007/s10620-019-05705-4 ◽

2019 ◽

Vol 64 (12) ◽

pp. 3518-3527 ◽

Cited By ~ 3

Author(s):

Xinhe Lou ◽

Huatuo Zhu ◽

Longgui Ning ◽

Chunxiao Li ◽

Sha Li ◽

...

Keyword(s):

Epithelial Cells ◽

Signaling Pathway ◽

Intestinal Inflammation ◽

Intestinal Epithelial Cells ◽

Intestinal Epithelial ◽

Jnk Signaling ◽

Jnk Signaling Pathway

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Alteration of gene expression by intestinal epithelial cells precedes colitis in interleukin-2-deficient mice

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1998.274.3.g472 ◽

1998 ◽

Vol 274 (3) ◽

pp. G472-G479 ◽

Cited By ~ 9

Author(s):

Maarten A. C. Meijssen ◽

Steven L. Brandwein ◽

Hans-Christian Reinecker ◽

Atul K. Bhan ◽

Daniel K. Podolsky

Keyword(s):

Epithelial Cells ◽

Intestinal Inflammation ◽

Intestinal Epithelial Cells ◽

Mrna Levels ◽

Intestinal Epithelial ◽

Colonic Epithelial Cells ◽

Tnf Α ◽

Small Intestinal ◽

Cd14 Mrna ◽

Tgf Β1

Intestinal epithelial cells may be actively involved in the immunoregulatory pathways leading to intestinal inflammation. The aim of this study was to assess expression by intestinal epithelial cells of cytokines with potential involvement in the development of intestinal inflammation in interleukin (IL)-2-deficient [(−/−)] mice. Wild-type mice, mice heterozygous for the disrupted IL-2 gene, and IL-2(−/−) mice were studied at 6, 16, and 24 wk of age. The mRNA levels of transforming growth factor-β1 (TGF-β1), tumor necrosis factor-α (TNF-α), IL-1β, IL-6, IL-15, KC, JE, and CD14 in colonic and small intestinal epithelial cells were assessed by Northern blot analysis. CD14 was also measured by Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR). TGF-β1 mRNA was constitutively expressed in both colonic and small intestinal epithelial cells with increased expression in the colonic epithelium of colitic mice. CD14 was detected only in colonic epithelial cells, and mRNA levels increased severalfold in IL-2(−/−) mice with colitis. Northern analysis demonstrated increased levels of TGF-β1 and CD14 mRNA in colonic epithelial cells of IL-2(−/−) mice before the development of signs of colitis. CD14 mRNA and protein expression in the epithelial cells of colitic mice were confirmed by RT-PCR and Western blot analysis of isolated cells. In addition, IL-2(−/−) mice also expressed increased levels of IL-15 mRNA in small intestinal and colonic epithelial cells compared with heterozygous control mice. TNF-α, IL-1β, IL-6, KC, and JE mRNAs were only detectable in colonic epithelial cells of mice after the onset of colitis. Enhanced expression of TGF-β1, IL-15, and CD14 by colonic epithelial cells may play a role in the subsequent development of colitis in IL-2(−/−) mice.

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Prohibitin Inhibits Tumor Necrosis Factor alpha–induced Nuclear Factor-kappa B Nuclear Translocation via the Novel Mechanism of Decreasing Importin α3 Expression

Molecular Biology of the Cell ◽

10.1091/mbc.e09-05-0361 ◽

2009 ◽

Vol 20 (20) ◽

pp. 4412-4423 ◽

Cited By ~ 45

Author(s):

Arianne L. Theiss ◽

Aaron K. Jenkins ◽

Ngozi I. Okoro ◽

Jan-Michael A. Klapproth ◽

Didier Merlin ◽

...

Keyword(s):

Epithelial Cells ◽

Intestinal Inflammation ◽

Nuclear Translocation ◽

Intestinal Epithelial Cells ◽

Intestinal Epithelial ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Factor Alpha

Expression of prohibitin 1 (PHB), a multifunctional protein in the cell, is decreased during inflammatory bowel disease (IBD). Little is known regarding the regulation and role of PHB during intestinal inflammation. We examined the effect of tumor necrosis factor alpha (TNF-α), a cytokine that plays a central role in the pathogenesis of IBD, on PHB expression and the effect of sustained PHB expression on TNF-α activation of nuclear factor-kappa B (NF-κB) and epithelial barrier dysfunction, two hallmarks of intestinal inflammation. We show that TNF-α decreased PHB protein and mRNA abundance in intestinal epithelial cells in vitro and in colon mucosa in vivo. Sustained expression of prohibitin in intestinal epithelial cells in vitro and in vivo (prohibitin transgenic mice, PHB TG) resulted in a marked decrease in TNF-α–induced nuclear translocation of the NF-κB protein p65, NF-κB/DNA binding, and NF-κB–mediated transcriptional activation despite robust IκB-α phosphorylation and degradation and increased cytosolic p65. Cells overexpressing PHB were protected from TNF-α–induced increased epithelial permeability. Expression of importin α3, a protein involved in p50/p65 nuclear import, was decreased in cells overexpressing PHB and in colon mucosa of PHB TG mice. Restoration of importin α3 levels sustained NF-κB activation by TNF-α during PHB transfection. These results suggest that PHB inhibits NF-κB nuclear translocation via a novel mechanism involving alteration of importin α3 levels. TNF-α decreases PHB expression in intestinal epithelial cells and restoration of PHB expression in these cells can protect against the deleterious effects of TNF-α and NF-κB on barrier function.

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Fluoxetine inhibits NF-κB signaling in intestinal epithelial cells and ameliorates experimental colitis and colitis-associated colon cancer in mice

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00267.2010 ◽

2011 ◽

Vol 301 (1) ◽

pp. G9-G19 ◽

Cited By ~ 46

Author(s):

Seong-Joon Koh ◽

Jung Mogg Kim ◽

In-Kyoung Kim ◽

Nayoung Kim ◽

Hyun Chae Jung ◽

...

Keyword(s):

Colon Cancer ◽

Epithelial Cells ◽

Intestinal Inflammation ◽

Intestinal Epithelial Cells ◽

Activity Index ◽

Myeloperoxidase Activity ◽

Intestinal Epithelial ◽

Murine Colitis ◽

Iκb Kinase ◽

Tnf Α

Although fluoxetine, a selective serotonin reuptake inhibitor, is known to demonstrate anti-inflammatory activity, little information is available on the effect of fluoxetine regarding intestinal inflammation. This study investigates the role of fluoxetine in the attenuation of acute murine colitis by suppression of the NF-κB pathway in intestinal epithelial cells (IEC). Fluoxetine significantly inhibited activated NF-κB signals and the upregulated expression of interleukin-8 (IL-8) in COLO 205 colon epithelial cells stimulated with tumor necrosis factor-α (TNF-α). Pretreatment with fluoxetine attenuated the increased IκB kinase (IKK) and IκBα phosphorylation induced by TNF-α. In a murine model, administration of fluoxetine significantly reduced the severity of dextran sulfate sodium (DSS)-induced colitis, as assessed by the disease activity index, colon length, and histology. In addition, the DSS-induced phospho-IKK activation, myeloperoxidase activity, a parameter of neutrophil accumulation, and the secretion of macrophage-inflammatory protein-2, a mouse homolog of IL-8, were significantly decreased in fluoxetine-pretreated mice. Moreover, fluoxetine significantly attenuated the development of colon cancer in mice inoculated with azoxymethane and DSS. These results indicate that fluoxetine inhibits NF-κB activation in IEC and that it ameliorates DSS-induced acute murine colitis and colitis-associated tumorigenesis, suggesting that fluoxetine is a potential therapeutic agent for the treatment of inflammatory bowel disease.

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Suppressing Syndecan-1 Shedding Ameliorates Intestinal Epithelial Inflammation through Inhibiting NF-κB Pathway and TNF-α

Gastroenterology Research and Practice ◽

10.1155/2016/6421351 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Yan Zhang ◽

Zhongqiu Wang ◽

Jun Liu ◽

Zhenyu Zhang ◽

Ye Chen

Keyword(s):

Epithelial Cells ◽

Intestinal Inflammation ◽

Inflammatory Responses ◽

Intestinal Epithelial Cells ◽

Underlying Mechanism ◽

Intestinal Epithelial ◽

Cell Models ◽

Tnf Α ◽

Epithelial Inflammation

Syndecan-1 (SDC1), with a long variable ectodomain carrying heparan sulfate chains, participates in many steps of inflammatory responses. But reports about the efforts of SDC1’s unshedding ectodomain on intestinal epithelial inflammation and the precise underlying mechanism are limited. In our study, unshedding SDC1 from intestinal epithelial cell models was established by transfecting with unshedding SDC1 plasmid into the cell, respectively. And the role of unshedding SDC1 in intestinal inflammation was further investigated. We found that components of NF-κB pathway, including P65 and IκBα, and secretion of TNF-αwere upregulated upon LPS stimulation in intestinal epithelial cells. SDC1, especially through its unshed ectodomain, significantly lessened the upregulation extent. It also functioned in inhibiting migration of neutrophils by downregulating secretion of CXCL-1. Taken together, we conclude that suppressing SDC1 shedding from intestinal epithelial cells relieves severity of intestinal inflammation by inactivating NF-κB pathway and downregulating TNF-αexpression. These results indicate that the ectodomain of SDC1 might be the optional therapy for intestinal inflammation.

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Spirulina Crude Protein Promotes the Migration and Proliferation in IEC-6 Cells by Activating EGFR/MAPK Signaling Pathway

Marine Drugs ◽

10.3390/md17040205 ◽

2019 ◽

Vol 17 (4) ◽

pp. 205

Author(s):

Su-Jin Jeong ◽

Jeong-Wook Choi ◽

Min-Kyeong Lee ◽

Youn-Hee Choi ◽

Taek-Jeong Nam

Keyword(s):

Cell Cycle ◽

Epithelial Cells ◽

Signaling Pathway ◽

Crude Protein ◽

Cell Cycle Progression ◽

Intestinal Epithelial Cells ◽

Mapk Signaling ◽

S Phase ◽

Intestinal Epithelial ◽

Cycle Progression

Spirulina is a type of filamentous blue-green microalgae known to be rich in nutrients and to have pharmacological effects, but the effect of spirulina on the small intestine epithelium is not well understood. Therefore, this study aims to investigate the proliferative effects of spirulina crude protein (SPCP) on a rat intestinal epithelial cells IEC-6 to elucidate the mechanisms underlying its effect. First, the results of wound-healing and cell viability assays demonstrated that SPCP promoted migration and proliferation in a dose-dependent manner. Subsequently, when the mechanisms of migration and proliferation promotion by SPCP were confirmed, we found that the epidermal growth factor receptor (EGFR) and mitogen-activated protein (MAPK) signaling pathways were activated by phosphorylation. Cell cycle progression from G0/G1 to S phase was also promoted by SPCP through upregulation of the expression levels of cyclins and cyclin-dependent kinases (Cdks), which regulate cell cycle progression to the S phase. Meanwhile, the expression of cyclin-dependent kinase inhibitors (CKIs), such as p21 and p27, decreased with SPCP. In conclusion, our results indicate that activation of EGFR and its downstream signaling pathway by SPCP treatment regulates cell cycle progression. Therefore, these results contribute to the research on the molecular mechanism for SPCP promoting the migration and proliferation of rat intestinal epithelial cells.

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