Galangin and Kaempferol Alleviate the Indomethacin-Caused Cytotoxicity and Barrier Loss in Rat Intestinal Epithelial (IEC-6) Cells Via Mediating JNK/Src Activation

Intestinal epithelial (IEC-6) cells are resistant to apoptosis following the inhibition of ODC (ornithine decarboxylase) and subsequent polyamine depletion. The depletion of polyamines rapidly activates NF-κB (nuclear factor κB) and STAT3 (signal transducer and activator of transcription 3), which is responsible for the observed decrease in apoptosis. Since both NF-κB and STAT3 signalling pathways can be activated by Src kinase, we examined its role in the antiapoptotic response. Inhibition of ODC by DFMO (α-difluoromethylornithine) increased the activity of Src and ERK1/2 (extracellular-signal-regulated kinase 1/2) within 30 min, which was prevented by exogenous polyamines added to the DFMO-containing medium. Conversely, epidermal growth factor-mediated Src and ERK1/2 activation was not prevented by the addition of polyamines. Inhibition of Src with PP2 {4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine} and a DN-Src (dominant-negative Src) construct prevented the activation of Akt, JAK (Janus kinase) and STAT3. Spontaneous apoptosis was increased in DN-Src-expressing cells and the protective effect of polyamine depletion was lost. Polyamine depletion by DFMO increased integrin β3 Tyr785 phosphorylation. Cells plated on fibronectin had significantly higher β3 phosphorylation and Src activation compared with plastic. Exogenous polyamines added to the fibronectin matrix prevented Src activation. Arg-Gly-Asp-Ser inhibited β3, Src and Akt phosphorylation and sensitized polyamine-depleted cells to tumour necrosis factor α/cycloheximide-mediated apoptosis. Fibronectin activated Src and subsequently protected cells from apoptosis. Together, these results suggest that the inhibition of ODC rapidly removes a small pool of available polyamines triggering the activation of β3 integrin, which in turn activates Src. The subsequent Akt and JAK activation is accompanied by translocation of NF-κB and STAT3 to the nucleus and the synthesis of antiapoptotic proteins.

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GPR35 promotes glycolysis, proliferation, and oncogenic signaling by engaging with the sodium potassium pump

Science Signaling ◽

10.1126/scisignal.aau9048 ◽

2019 ◽

Vol 12 (562) ◽

pp. eaau9048 ◽

Cited By ~ 11

Author(s):

Georg Schneditz ◽

Joshua E. Elias ◽

Ester Pagano ◽

M. Zaeem Cader ◽

Svetlana Saveljeva ◽

...

Keyword(s):

Metabolic Activity ◽

Inflammatory Diseases ◽

Intestinal Epithelial ◽

Oncogenic Signaling ◽

Independent Manner ◽

Sodium Potassium ◽

Src Signaling ◽

High Cancer Risk ◽

Sodium Potassium Pump ◽

Src Activation

The sodium potassium pump (Na/K-ATPase) ensures the electrochemical gradient of a cell through an energy-dependent process that consumes about one-third of regenerated ATP. We report that the G protein–coupled receptor GPR35 interacted with the α chain of Na/K-ATPase and promotes its ion transport and Src signaling activity in a ligand-independent manner. Deletion of Gpr35 increased baseline Ca2+to maximal levels and reduced Src activation and overall metabolic activity in macrophages and intestinal epithelial cells (IECs). In contrast, a common T108M polymorphism in GPR35 was hypermorphic and had the opposite effects to Gpr35 deletion on Src activation and metabolic activity. The T108M polymorphism is associated with ulcerative colitis and primary sclerosing cholangitis, inflammatory diseases with a high cancer risk. GPR35 promoted homeostatic IEC turnover, whereas Gpr35 deletion or inhibition by a selective pepducin prevented inflammation-associated and spontaneous intestinal tumorigenesis in mice. Thus, GPR35 acts as a central signaling and metabolic pacesetter, which reveals an unexpected role of Na/K-ATPase in macrophage and IEC biology.

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HB-EGF induces focal adhesion kinase via ErbB-1/ src activation in non-transformed rat intestinal epithelial (RIE-1) cells

Journal of Surgical Research ◽

10.1016/j.jss.2005.11.269 ◽

2006 ◽

Vol 130 (2) ◽

pp. 255

Author(s):

O.N. El-Assal ◽

G.E. Besner

Keyword(s):

Focal Adhesion Kinase ◽

Focal Adhesion ◽

Intestinal Epithelial ◽

Src Activation

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Membrane-bound vesicles associated with the microvilli in the midgut of the freshwater microcrustacean, Daphnia magna

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076135 ◽

1983 ◽

Vol 41 ◽

pp. 480-481

Author(s):

Patricia L. Jansma

Keyword(s):

Daphnia Magna ◽

Intestinal Epithelial Cells ◽

Uranyl Acetate ◽

Intestinal Epithelial ◽

Chlamydomonas Reinhardii ◽

Thin Sections ◽

Saturated Water ◽

Cacodylate Buffer ◽

Membrane Bound ◽

Ethanol Series

The presence of the membrane bound vesicles or blebs on the intestinal epithelial cells has been demonstrated in a variety of vertebrates such as chicks, piglets, hamsters, and humans. The only invertebrates shown to have these microvillar blebs are two species of f1ies. While investigating the digestive processes of the freshwater microcrustacean, Daphnia magna, the presence of these microvillar blebs was noticed.Daphnia magna fed in a suspension of axenically grown green alga, Chlamydomonas reinhardii for one hour were narcotized with CO2 saturated water. The intestinal tracts were excised in 2% glutaraldehyde in 0.2 M cacodyl ate buffer and then placed in fresh 2% glutaraldehyde for one hour. After rinsing in 0.1 M cacodylate buffer, the sample was postfixed in 2% OsO4, dehydrated with a graded ethanol series, infiltrated and embedded with Epon-Araldite. Thin sections were stained with uranyl acetate and Reynolds lead citrate before viewing with the Philips EM 200.

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The protease phenotype and crystalline nature of the granules of intraepithelial mast cells in Trichinella spiralis-infected mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140464 ◽

1995 ◽

Vol 53 ◽

pp. 818-819

Author(s):

D.S. Friend ◽

N. Ghildyal ◽

M.F. Gurish ◽

K.F. Austen ◽

R.L. Stevens

Keyword(s):

Small Intestine ◽

Mast Cells ◽

Epithelial Cells ◽

Lamina Propria ◽

Trichinella Spiralis ◽

Intestinal Epithelial ◽

Carboxypeptidase A ◽

C3h Mice ◽

Granule Morphology ◽

Crystalline Nature

Trichinella spiralis induces a profound mastocytosis and eosinophilia in the small intestine of the infected mouse. Mouse mast cells (MC) store in their granules various combinations of at least five chymotryptic chymases [designated mouse MC protease (mMCP) 1 to 5], two tryptic proteases designated mMCP-6 and mMCP-7 and an exopeptidase, carboxypeptidase A (mMC-CPA). Using antipeptide, protease -specific antibodies to these MC granule proteases, immunohistochemistry was done to determine the distribution, number and protease phenotype of the MCs in the small intestine and spleen 10 to >60 days after Trichinella infection of BALB/c and C3H mice. TEM was performed to evaluate the granule morphology of the MCs between intestinal epithelial cells and in the lamina propria (mucosal MCs) and in the submucosa, muscle and serosa of the intestine (submucosal MCs).As noted in the table below, the number of submucosal MCs remained constant throughout the study. In contrast, on day 14, the number of MCs in the mucosa increased ~25 fold. Increased numbers of MCs were observed between epithelial cells in the mucosal crypts, in the lamina propria and to a lesser extent, between epithelial cells of the intestinal villi.

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Three-dimensional organization and functional relationships of endocytotic compartments in pig intestinal epithelial cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123283 ◽

1992 ◽

Vol 50 (1) ◽

pp. 576-577

Author(s):

Julian P. Heath ◽

Buford L. Nichols ◽

László G. Kömüves

Keyword(s):

Electron Microscopy ◽

Epithelial Cells ◽

Intestinal Epithelial Cells ◽

Three Dimensional ◽

Intestinal Epithelial ◽

Cell Surfaces ◽

Basal Surface ◽

Functional Relationships

The newborn pig intestine is adapted for the rapid and efficient absorption of nutrients from colostrum. In enterocytes, colostral proteins are taken up into an apical endocytotic complex of channels that transports them to target organelles or to the basal surface for release into the circulation. The apical endocytotic complex of tubules and vesicles clearly is a major intersection in the routes taken by vesicles trafficking to and from the Golgi, lysosomes, and the apical and basolateral cell surfaces.Jejunal tissues were taken from piglets suckled for up to 6 hours and prepared for electron microscopy and immunocytochemistry as previously described.

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An immunocytochemical study of maternal immunoglobulin localization in the suckling pig intestine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016217x ◽

1990 ◽

Vol 48 (3) ◽

pp. 922-923

Author(s):

László G. Kömüves ◽

Donna S. Turner ◽

Kathy S. McKee ◽

Buford L. Nichols ◽

Julian P. Heath

Keyword(s):

Sodium Ethoxide ◽

Intracellular Localization ◽

Protein A ◽

Tween 20 ◽

Intestinal Epithelial ◽

Immunocytochemical Study ◽

Fish Skin ◽

Newborn Piglets ◽

Rabbit Igg ◽

Fish Skin Gelatin

In this study we used colloidal gold probes to detect the intracellular localization of colostral immunoglobulins in intestinal epithelial cells of newborn piglets.Tissues were obtained from non-suckled newborn and suckled piglets aged between 1 hour to 1 month. Samples were fixed in 2.5 % glutaraldehyde, osmicated and embedded into Spurr’s resin. Thin (80 nm) sections were etched with 5% sodium ethoxide for 5 min, washed and treated with 4 % sodium-m-periodate in distilled water for 30 min. The sections were then first incubated with blocking buffer (2 % BSA, 0.25 % fish skin gelatin, 0.5 % Tween 20 in 10 mM Trizma buffer, pH=7.4 containing 500 mM NaCl) for 30 min followed by the immunoreagents diluted in the same buffer, 1 hr each. For the detection of pig immunoglobulins a rabbit anti-pig IgG antiserum was used followed by goat anti-rabbit IgG-Au10 or protein A-Au15 probes.

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