scholarly journals Cryptosporidial Infection Suppresses Intestinal Epithelial Cell MAPK Signaling Impairing Host Anti-Parasitic Defense

2021 ◽  
Vol 9 (1) ◽  
pp. 151
Author(s):  
Wei He ◽  
Juan Li ◽  
Ai-Yu Gong ◽  
Silu Deng ◽  
Min Li ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Mapk Signaling ◽  
Host Cells ◽  
Intestinal Epithelial ◽  
Cryptosporidium Infection ◽  
Cryptosporidial Infection

Cryptosporidium is a genus of protozoan parasites that infect the gastrointestinal epithelium of a variety of vertebrate hosts. Intestinal epithelial cells are the first line of defense and play a critical role in orchestrating host immunity against Cryptosporidium infection. To counteract host defense response, Cryptosporidium has developed strategies of immune evasion to promote parasitic replication and survival within epithelial cells, but the underlying mechanisms are largely unclear. Using various models of intestinal cryptosporidiosis, we found that Cryptosporidium infection caused suppression of mitogen-activated protein kinase (MAPK) signaling in infected murine intestinal epithelial cells. Whereas expression levels of most genes encoding the key components of the MAPK signaling pathway were not changed in infected intestinal epithelial cells, we detected a significant downregulation of p38/Mapk, MAP kinase-activated protein kinase 2 (Mk2), and Mk3 genes in infected host cells. Suppression of MAPK signaling was associated with an impaired intestinal epithelial defense against C. parvum infection. Our data suggest that cryptosporidial infection may suppress intestinal epithelial cell MAPK signaling associated with the evasion of host antimicrobial defense.

scholarly journals Rapid protein kinase D1 signaling promotes migration of intestinal epithelial cells

2012 ◽  
Vol 303 (3) ◽  
pp. G356-G366 ◽  
Author(s):  
Steven H. Young ◽  
Nora Rozengurt ◽  
James Sinnett-Smith ◽  
Enrique Rozengurt
Keyword(s):  
Protein Kinase ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Transgenic Mice ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Intestinal Epithelial ◽  
Protein Kinase D1

We have examined the role of protein kinase D1 (PKD1) signaling in intestinal epithelial cell migration. Wounding monolayer cultures of intestinal epithelial cell line IEC-18 or IEC-6 induced rapid PKD1 activation in the cells immediately adjacent to the wound edge, as judged by immunofluorescence microscopy with an antibody that detects the phosphorylated state of PKD1 at Ser916, an autophosphorylation site. An increase in PKD1 phosphorylation at Ser916 was evident as early as 45 s after wounding, reached a maximum after 3 min, and persisted for ≥15 min. PKD1 autophosphorylation at Ser916 was prevented by the PKD family inhibitors kb NB 142-70 and CRT0066101. A kb NB 142-70-sensitive increase in PKD autophosphorylation was also elicited by wounding IEC-6 cells. Using in vitro kinase assays after PKD1 immunoprecipitation, we corroborated that wounding IEC-18 cells induced rapid PKD1 catalytic activation. Further results indicate that PKD1 signaling is required to promote migration of intestinal epithelial cells into the denuded area of the wound. Specifically, treatment with kb NB 142-70 or small interfering RNAs targeting PKD1 markedly reduced wound-induced migration in IEC-18 cells. To test whether PKD1 promotes migration of intestinal epithelial cells in vivo, we used transgenic mice that express elevated PKD1 protein in the small intestinal epithelium. Enterocyte migration was markedly increased in the PKD1 transgenic mice. These results demonstrate that PKD1 activation is one of the early events initiated by wounding a monolayer of intestinal epithelial cells and indicate that PKD1 signaling promotes the migration of these cells in vitro and in vivo.

scholarly journals Schisandrin A protects intestinal cells from mycophenolic acid-induced cytotoxicity and oxidative damage

2021 ◽  
Author(s):  
Yiyun Deng ◽  
Zhe Zhang ◽  
Yuanyuan Hong ◽  
Lijuan Feng ◽  
Yong Su ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Oxidative Damage ◽  
Mycophenolic Acid ◽  
Cell Apoptosis ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Mapk Signaling ◽  
Intestinal Epithelial

Abstract Objectives: The gastrointestinal side effects of mycophenolic acid affect its efficacy in kidney transplant patients, which may be due to its toxicity to the intestinal epithelial mechanical barrier, including intestinal epithelial cell apoptosis and destruction of tight junctions. The toxicity mechanism of mycophenolic acid is related to oxidative stress-mediated the activation of mitogen-activated protein kinases (MAP K). Schisandrin A (Sch A), one of the main active components of the Schisandra chinensis, can protects intestinal epithelial cells from deoxynivalenol-induced cytotoxicity and oxidative damage by antioxidant effects. The aim of this study was to investigate the protective effect and potential mechanism of Sch A on mycophenolic acid-induced damage in intestinal epithelial cell. Methods: Caco-2 cells monolayers were treated with mycophenolic acid (10µM) and/or Sch A (10, 20 and 40µM) at 37°C for 24h, and cell viability was measured by MTT; Western blot and immunofluorescence were used to detect the expression of relevant proteins. Intracellular ROS and apoptosis were measured by flow cytometry, and malondialdehyde (MDA) and superoxide dismutase (SOD) levels were measured by kits. Results: The results showed that Sch A significantly reversed the mycophenolic acid-induced cell viability reduction, restored the expression of tight junction protein ZO-1, occludin and reduced cell apoptosis. In addition, Sch A inhibited mycophenolic acid-mediated MAPK activation and reactive oxygen species (ROS) increase. Conclusions: Sch A protected intestinal epithelial cells from mycophenolic acid intestinal toxicity, at least in part, by reducing oxidative stress and inhibiting MAPK signaling pathway. Conclusions: Sch A protected intestinal epithelial cells from mycophenolic acid intestinal toxicity, at least in part, by reducing oxidative stress and inhibiting MAPK signaling pathway.

Induction of endothelin-1 synthesis by IL-2 and its modulation of rat intestinal epithelial cell growth

1998 ◽  
Vol 275 (3) ◽  
pp. G556-G563 ◽  
Author(s):  
Takeharu Shigematsu ◽  
Soichiro Miura ◽  
Masahiko Hirokawa ◽  
Ryota Hokari ◽  
Hajime Higuchi ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Growth ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Lines ◽  
Proliferative Response ◽  
Intestinal Epithelial Cell ◽  
Culture Media ◽  
Intestinal Epithelial Cells ◽  
Intestinal Epithelial

Endothelin (ET), a vasoconstrictive peptide, is known to have a variety of biological actions. Although ET is released by vascular endothelial cells, other cell populations also have been reported to synthesize and release ET. In this study, we examined whether ET is synthesized by intestinal epithelial cells and whether it affects induction of epithelial cell proliferation by interleukin-2 (IL-2). Subconfluent monolayers of intestinal epithelial cells (IEC-6 and IEC-18) were maintained in serum-free medium before addition of rat IL-2. Both IEC-6 and IEC-18 cells released ET-1 into the medium under unstimulated conditions, as determined by a sandwich ELISA. IL-2 significantly enhanced ET-1 release in a time-dependent manner. ET-3 was not detectable in the culture media of either cell line. Expression of ET-1 and ET-3 mRNA in epithelial cells was assessed by competitive PCR. Both cell lines were shown to express ET-1 mRNA, but no ET-3 mRNA was detected. IL-2 treatment enhanced ET-1 mRNA expression by both IEC-6 and IEC-18 cells. Both cell lines also expressed mRNA for ETA and ETB receptor subtypes. When cell proliferation was assessed, exogenous ET-1 induced a slight proliferative response in both types of cells that was consistent and significant at low ET-1 concentrations; cell growth was inhibited at a higher concentration (10−7M). IL-2 produced a significant proliferative response in both cell lines. However, the addition of ET-1 (10−7 M) to culture media attenuated the IL-2-induced increase in cell proliferation. ETA-receptor antagonists significantly enhanced cellular proliferation, suggesting involvement of the ETA receptor in modulation of IL-2-induced intestinal epithelial cell growth.

Oxidative stress enhances IL-8 and inhibits CCL20 production from intestinal epithelial cells in response to bacterial flagellin

2010 ◽  
Vol 299 (3) ◽  
pp. G733-G741 ◽  
Author(s):  
Sabine M. Ivison ◽  
Ce Wang ◽  
Megan E. Himmel ◽  
Jared Sheridan ◽  
Jonathan Delano ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Protein Kinase ◽  
Epithelial Cells ◽  
Pathogenic Bacteria ◽  
Intestinal Epithelial Cells ◽  
Host Cells ◽  
Dependent Manner ◽  
Intestinal Epithelial ◽  
Chemokine Production ◽  
Molecular Signals

Intestinal epithelial cells act as innate immune sentinels, as the first cells that encounter diarrheal pathogens. They use pattern recognition molecules such as the Toll-like receptors (TLRs) to identify molecular signals found on microbes but not host cells or food components. TLRs cannot generally distinguish the molecular signals on pathogenic bacteria from those found in commensals, yet under healthy conditions epithelial immune responses are kept in check. We hypothesized that, in the setting of tissue damage or stress, intestinal epithelial cells would upregulate their responses to TLR ligands to reflect the greater need for immediate protection against pathogens. We treated Caco-2 cells with the TLR5 agonist flagellin in the presence or absence of H2O2 and measured chemokine production and intracellular signaling pathways. H2O2 increased flagellin-induced IL-8 (CXCL8) production in a dose-dependent manner. This was associated with synergistic phosphorylation of p38 MAP kinase and with prolonged I-κB degradation and NF-κB activation. The H2O2-mediated potentiation of IL-8 production required the activity of p38, tyrosine kinases, phospholipase Cγ, and intracellular calcium, but not protein kinase C or protein kinase D. H2O2 prolonged and augmented NF-κB activation by flagellin. In contrast to IL-8, CCL20 (MIP3α) production by flagellin was reduced by H2O2, and this effect was not calcium dependent. Oxidative stress biases intestinal epithelial responses to flagellin, leading to increased production of IL-8 and decreased production of CCL20. This suggests that epithelial cells are capable of sensing the extracellular environment and adjusting their antimicrobial responses accordingly.

scholarly journals PSIX-17 Investigating the biological activities of sodium cellobionate produced from cellulosic biomass

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 187-187
Author(s):  
Lauren Kovanda ◽  
Zhiliang Fan ◽  
Xunde Li ◽  
Yanhong Liu
Keyword(s):  
Cell Proliferation ◽  
Antimicrobial Activity ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Biological Activities ◽  
Radical Scavenging ◽  
Intestinal Epithelial

Abstract A novel method has been developed to easily hydrolyze cellulose to sodium cellobionate in a filamentous fungas, Neurospora crassa. The objectives of this experiment were to investigate the in vitro biological activities of sodium cellobionate. Antioxidant activity was evaluated with 3 chemical-based assays, including DPPH radical scavenging assay (DPPH), Trolox equivalent antioxidant capacity assay (TEAC), and ferric reducing antioxidant power assay (FRAP). Antimicrobial activity was determined as minimum inhibitory concentration (MIC) that prevented growth of tested bacteria, including four gram-negative bacteria (Escherichia coli F18 and ATCC 25922, and Salmonella Typhimurium ATCC 14028 and a wild strain isolated from cull diary cows in California) and one gram-positive bacteria (Enterococcus faecalis ATCC 29212). Anti-inflammatory activity was tested by analyzing TNF-α production with porcine alveolar macrophages that were challenged with lipopolysaccharide. A porcine intestinal epithelial cell line, IPEC-J2, was also used to test the effects of cellobionate on cell proliferation of intestinal epithelial cells. The tested doses of sodium cellobionate were 0, 0.04, 0.20, 1.00, 2.00, 4.00, 20.00, and 40.00 mg/mL. All assays were performed with over 6 replicates, except that MIC assays were performed as triplicate. All data were analyzed by PROC MIXED of SAS. Sodium cellobionate did not have radical scavenging capacity, but had weak FRAP (9.68 μM L-Cysteine equivalent) and TEAC (69% reduction) at the dose of 40 mg/mL. MIC results revealed that sodium cellobionate did not inhibit the growth of all tested bacteria, indicating it does not have antimicrobial activity within the range of tested doses. Sodium cellobionate did not exhibit anti-inflammatory activities, but significantly enhanced (P < 0.05) intestinal epithelial cell proliferation in vitro by 24.00%, 39.64%, and 25.98% when the doses were 1.00, 2.00, and 4.00 mg/mL, respectively. Results of this experiment indicate that cellobionate has limited biological activities in vitro, except that this biomass product could strongly stimulate the proliferation of intestinal epithelial cells. Future research will focus on the potential impacts of sodium cellobionate on intestinal physiology in vivo.

Iron chelation acutely stimulates fetal human intestinal cell production of IL-6 and VEGF while decreasing HGF: the roles of p38, ERK, and JNK MAPK signaling

2007 ◽  
Vol 292 (4) ◽  
pp. G958-G963 ◽  
Author(s):  
Troy A. Markel ◽  
Paul R. Crisostomo ◽  
Meijing Wang ◽  
Christine M. Herring ◽  
Tim Lahm ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
P38 Mapk ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Iron Chelation ◽  
Intestinal Epithelial ◽  
Cell Production ◽  
Human Intestinal Epithelial Cells ◽  
Tnf Α

Bacteria have developed mechanisms to sequester host iron via chelators such as deferoxamine (DFO). Interestingly, DFO has been shown to stimulate acute intestinal epithelial cell inflammatory cytokine production in the absence of bacteria; however, this mechanism has not been elucidated. Intestinal epithelial cell production of IL-6 and TNF-α is elevated in various gastrointestinal pathologies, including acute intestinal ischemia. Similarly, VEGF and HGF are essential to intestinal epithelial cell integrity. Therapeutic strategies that decrease IL-6 and TNF-α while increasing VEGF and HGF therefore have theoretical appeal. We hypothesized that 1) fetal human intestinal epithelial cells acutely produce increased IL-6, TNF-α, VEGF, and HGF during iron chelation and 2) the MAPK pathway mediates these effects. Fetal human intestinal epithelial cells were stimulated by iron chelation (1 mM DFO) with and without p38 MAPK, ERK, or JNK inhibition. Supernatants were harvested after 24 h of incubation, and IL-6, TNF-α, VEGF, and HGF levels were quantified by ELISA. Activation of MAPK pathways was confirmed by Western blot analysis. DFO stimulation resulted in a significant increase in epithelial cell IL-6 and VEGF production while yielding a decrease in HGF production ( P < 0.05). Unexpectedly, TNF-α was not detectable. p38 MAPK, ERK, and JNK inhibition significantly decreased IL-6, VEGF, and HGF production ( P < 0.05). In conclusion, DFO acutely increases fetal human intestinal epithelial cell IL-6 and VEGF expression while causing an unexpected decrease in HGF expression and no detectable TNF-α production. Furthermore, chelator-induced intestinal epithelial cell cytokine expression depends on p38, ERK, and JNK MAPK pathways.

scholarly journals Lactobacillus acidophilus Induces Cytokine and Chemokine Production via NF-κB and p38 Mitogen-Activated Protein Kinase Signaling Pathways in Intestinal Epithelial Cells

2012 ◽  
Vol 19 (4) ◽  
pp. 603-608 ◽  
Author(s):  
Yujun Jiang ◽  
Xuena Lü ◽  
Chaoxin Man ◽  
Linlin Han ◽  
Yi Shan ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Lines ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Intestinal Epithelial ◽  
Chemokine Production ◽  
Content Type ◽  
Cytokines And Chemokines ◽  
Epithelial Cell Lines

ABSTRACTIntestinal epithelial cells can respond to certain bacteria by producing an array of cytokines and chemokines which are associated with host immune responses.Lactobacillus acidophilusNCFM is a characterized probiotic, originally isolated from human feces. This study aimed to test the ability ofL. acidophilusNCFM to stimulate cytokine and chemokine production in intestinal epithelial cells and to elucidate the mechanisms involved in their upregulation. In experiments using intestinal epithelial cell lines and mouse models, we observed thatL. acidophilusNCFM could rapidly but transiently upregulate a number of effector genes encoding cytokines and chemokines such as interleukin 1α (IL-1α), IL-1β, CCL2, and CCL20 and that cytokines showed lower expression levels withL. acidophilusNCFM treatment than chemokines. Moreover,L. acidophilusNCFM could activate a pathogen-associated molecular pattern receptor, Toll-like receptor 2 (TLR2), in intestinal epithelial cell lines. The phosphorylation of NF-κB p65 and p38 mitogen-activated protein kinase (MAPK) in intestinal epithelial cell lines was also enhanced byL. acidophilusNCFM. Furthermore, inhibitors of NF-κB (pyrrolidine dithiocarbamate [PDTC]) and p38 MAPK (SB203580) significantly reduced cytokine and chemokine production in the intestinal epithelial cell lines stimulated byL. acidophilusNCFM, suggesting that both NF-κB and p38 MAPK signaling pathways were important for the production of cytokines and chemokines induced byL. acidophilusNCFM.

Ca2+-sensing receptors in intestinal epithelium

1997 ◽  
Vol 273 (4) ◽  
pp. C1168-C1175 ◽  
Author(s):  
Lucio Gama ◽  
Lynn M. Baxendale-Cox ◽  
Gerda E. Breitwieser
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Intestinal Epithelium ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Northern Blotting ◽  
Intestinal Epithelial ◽  
Pcr Products ◽  
Intracellular Ca ◽  
Ht 29

Expression of Ca2+-sensing receptors (CaR) was demonstrated in several human intestinal epithelial cell lines (T84, HT-29, and Caco-2) and in rat intestinal epithelium by both reverse transcriptase-polymerase chain reaction (PCR) and Northern blotting of RNA. Restriction patterns of the PCR products were of the sizes predicted by the human and rat sequences. CaR agonists (Ca2+, poly-l-arginine, protamine) mediated an increase in intracellular Ca2+ in HT-29–18-C1 cells (monitored by changes in fura 2 fluorescence), which was dependent on release from thapsigargin-sensitive stores. U-73122, an inhibitor of phosphatidylinositol-phospholipase C, eliminated the CaR agonist-mediated rise in intracellular Ca2+, whereas its inactive analog, U-73343, had no effect. Pertussis toxin pretreatment had no effect on CaR agonist-mediated modulation of intracellular Ca2+. Taken together, these studies demonstrate that CaR are expressed in intestinal epithelial cells and couple to mobilization of intracellular Ca2+. The presence of CaR in intestinal epithelial cells presents a new locus for investigations into the role(s) of extracellular Ca2+ in modulating intestinal epithelial cell differentiation and transepithelial Ca2+ transport.

ADAM-15 inhibits wound healing in human intestinal epithelial cell monolayers

2005 ◽  
Vol 288 (2) ◽  
pp. G346-G353 ◽  
Author(s):  
Laetitia Charrier ◽  
Yutao Yan ◽  
Adel Driss ◽  
Christian L. Laboisse ◽  
Shanthi V. Sitaraman ◽  
...  
Keyword(s):  
Wound Healing ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Epithelial Cell Line ◽  
Intestinal Epithelial ◽  
Coding Region ◽  
Human Intestinal Epithelial Cell ◽  
New Variant

The disintegrin metalloproteases (or ADAMs) are membrane-anchored glycoproteins that have been implicated in cell-cell or cell-matrix interactions and in proteolysis of molecules on the cell surface. The expression and/or the pathophysiological implications of ADAMs are not known in intestinal epithelial cells. Therefore, our aim was to investigate the expression and the role of ADAMs in intestinal epithelial cells. Expression of ADAMs was assessed by RT-PCR, Western blot analysis, and immunufluorescence experiments. Wound-healing experiments were performed by using the electric cell substrate impedence sensing technology. Our results showed that ADAMs-10, -12, and -15 mRNA are expressed in the colonic human cell lines Caco2-BBE and HT29-Cl.19A. An ADAM-15 complementary DNA cloned from Caco2-BBE poly(A)+ RNA, and encompassing the entire coding region, was found to be shorter and to present a different region encoding the cytoplasmic tail compared with ADAM-15 sequence deposited in the database. In Caco2-BBE cells and colonic epithelial cells, ADAM-15 protein was found in the apical, basolateral, and intracellular compartments. We also showed that the overexpression of ADAM-15 reduced cell migration in a wound-healing assay in Caco2-BBE monolayers. Our data show that 1) ADAM-15 is expressed in human intestinal epithelia, 2) a new variant of ADAM-15 is expressed in a human intestinal epithelial cell line, and 3) ADAM-15 is involved in intestinal epithelial cells wound-healing processes. Together, these results suggest that ADAM-15 may have important pathophysiological roles in intestinal cells.

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