Leptin modulates the expression of secreted and membrane-associated mucins in colonic epithelial cells by targeting PKC, PI3K, and MAPK pathways

2007 ◽  
Vol 293 (1) ◽  
pp. G365-G373 ◽  
Author(s):  
Mahmoud El Homsi ◽  
Robert Ducroc ◽  
Jean Claustre ◽  
Gérard Jourdan ◽  
Arieh Gertler ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Mrna Level ◽  
Intestinal Barrier Function ◽  
Rat Colon ◽  
Mrna Levels ◽  
Colonic Epithelial Cells ◽  
Mucin Production ◽  
Leptin Receptors ◽  
Mucin Expression

Mucins play an essential role in the protection and repair of gastrointestinal mucosa. We recently showed that luminal leptin strongly stimulated mucin secretion in vivo in rat colon. In the present study, we challenged the hypothesis that leptin may act directly on goblet cells to induce mucin expression in rat and human intestinal mucin-producing cells (DHE and HT29-MTX). The endoluminal effect of leptin was also studied in vivo in rat perfused colon model. The presence of leptin receptors was demonstrated in the two cell lines by Western blot and RT-PCR. In rat DHE cells, leptin (0.01–10 nmol/l, 60 min) dose dependently increased the secretion of mucins (210 ± 3% of controls) and the expression of Muc2, Muc3, and Muc4 (twofold basal level) but not of Muc1 and Muc5AC. Luminal perfusion of leptin (60 min, 0.1–100 nmol/l) in rat colon also increased the mRNA level of Muc2, Muc3, and Muc4 but not of Muc1. In human HT29-MTX cells, leptin (0.01–10 nmol/l, 60 min) dose dependently enhanced MUC2, MUC5AC, and MUC4 mRNA levels. These effects were prevented by pretreatment of cells with the leptin mutein L39A/D40A/F41A, which acts as a receptor antagonist. Finally, pathway inhibition experiments suggest that leptin increased mucin expression by activating PKC-, phosphatidyl inositol 3-kinase-, and MAPK-dependent pathways but not the JAK/STAT pathway. In conclusion, leptin may contribute significantly to membrane-associated and secreted mucin production via a direct stimulation of colonic epithelial cells and the activation of leptin receptors. These data are consistent with a role for leptin in regulation of the intestinal barrier function.

11 beta-hydroxysteroid dehydrogenase and corticosteroid hormone receptors in the rat colon

1993 ◽  
Vol 264 (6) ◽  
pp. E951-E957 ◽  
Author(s):  
C. B. Whorwood ◽  
P. C. Barber ◽  
J. Gregory ◽  
M. C. Sheppard ◽  
P. M. Stewart
Keyword(s):  
Epithelial Cells ◽  
Lamina Propria ◽  
Hormone Receptors ◽  
Rat Kidney ◽  
Distal Colon ◽  
Hydroxysteroid Dehydrogenase ◽  
Neuroendocrine Cells ◽  
Rat Colon ◽  
Mrna Levels

In the rat kidney 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) maintains normal in vivo specificity for mineralocorticoid receptor (MR) by converting the active steroid corticosterone to inactive 11-dehydrocorticosterone, leaving aldosterone to occupy the MR. Clinical observations support the hypothesis that 11 beta-HSD also protects the distal colonic MR from glucocorticoid excess. We have measured 11 beta-HSD mRNA and activity along the rat colon and have analyzed the distribution of 11 beta-HSD, MR, and glucocorticoid receptor (GR) mRNA within rat distal colon using in situ hybridization. Levels of 11 beta-HSD mRNA (1.7 and 3.4 kb) and activity were higher in distal vs. proximal colon, paralleling reported MR mRNA levels. Within the distal colon mucosa both 11 beta-HSD immunoreactivity and mRNA was observed in cells in the lamina propria but not in epithelial cells. MR mRNA was present in surface epithelial cells, but was also colocalized with the same 11 beta-HSD-expressing cells in the lamina propria. In contrast GR mRNA was more uniformly distributed. The localization of MR mRNA to nonepithelial cells in the lamina propria, possibly neuroendocrine cells, suggests that mineralocorticoid-regulated sodium transport across colonic epithelial cells may also involve a paracrine mechanism. As with the kidney, exposure of active mineralocorticoid to the MR in these cells in the lamina propria is dictated by 11 beta-HSD in an autocrine fashion.

EFFECT OF ALDOSTERONE ON LITHIUM PERMEABILITY OF RAT COLON MUCOSA

1976 ◽  
Vol 70 (1) ◽  
pp. 135-140 ◽  
Author(s):  
DIANA DOLMAN ◽  
C. J. EDMONDS ◽  
C. SALAS-COLL
Keyword(s):  
Epithelial Cells ◽  
Electrical Resistance ◽  
Absorption Rate ◽  
Ionic Composition ◽  
Rat Colon ◽  
Sodium Absorption ◽  
Epithelial Layer ◽  
Colonic Epithelial Cells ◽  
Sodium And Potassium

SUMMARY The effect of aldosterone on the ionic composition of colonic epithelial cells and on lithium absorption rate was studied by experiments on rats in vivo. Aldosterone considerably increased the rate of sodium absorption without measurably altering the sodium and potassium content of the epithelium. Aldosterone did not alter the electrical resistance of the tissue. With lithium in the lumen, the net sodium fluxes in the colon were similar in normal and aldosterone-stimulated rats but the rate of diffusion of lithium across the epithelium was greater in the aldosterone-stimulated group. The amount of lithium accumulating in the epithelial layer was also considerably increased by aldosterone stimulation. Aldosterone appears to increase the permeability of the mucosal (luminal) barrier allowing increased entry of lithium into the colonic epithelial cells.

Cytokine-induced changes in chromatin structure and in vivo footprints in the inducible NOS promoter

2001 ◽  
Vol 280 (3) ◽  
pp. L390-L399 ◽  
Author(s):  
Jane K. Mellott ◽  
Harry S. Nick ◽  
Michael F. Waters ◽  
Timothy R. Billiar ◽  
David A. Geller ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Protein Interactions ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Specific Pattern ◽  
Mrna Levels ◽  
Inos Gene ◽  
In Vivo Footprinting ◽  
Induced Changes

Transcription of the human inducible nitric oxide synthase ( iNOS) gene is regulated by inflammatory cytokines in a tissue-specific manner. To determine whether differences in cytokine-induced mRNA levels between pulmonary epithelial cells (A549) and hepatic biliary epithelial cells (AKN-1) result from different protein or DNA regulatory mechanisms, we identified cytokine-induced changes in DNase I-hypersensitive (HS) sites in 13 kb of the iNOS 5′-flanking region. Data showed both constitutive and inducible HS sites in an overlapping yet cell type-specific pattern. Using in vivo footprinting and ligation-mediated PCR to detect potential DNA or protein interactions, we examined one promoter region near −5 kb containing both constitutive and cytokine-induced HS sites. In both cell types, three in vivo footprints were present in both control and cytokine-treated cells, and each mapped within a constitutive HS site. The remaining footprint appeared only in response to cytokine treatment and mapped to an inducible HS site. These studies, performed on chromatin in situ, identify a portion of the molecular mechanisms regulating transcription of the human iNOS gene in both lung- and liver-derived epithelial cells.

Fatty-acid synthase activity and mRNA level in hypertrophic type II cells from silica-treated rats

1994 ◽  
Vol 267 (2) ◽  
pp. L128-L136
Author(s):  
J. Rami ◽  
W. Stenzel ◽  
S. M. Sasic ◽  
C. Puel-M'Rini ◽  
J. P. Besombes ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Fatty Acid Biosynthesis ◽  
De Novo ◽  
Mrna Level ◽  
Type Ii Cells ◽  
Mrna Levels ◽  
Type Ii ◽  
Maximum Increase

Silica instillation causes a massive increase in lung surfactant. Two populations of type II pneumocytes can be isolated from rats administered silica by intratracheal injection: type IIA cells similar to type II cells from normal rats and type IIB cells, which are larger and contain elevated levels of surfactant protein A and phospholipid. Activities of choline-phosphate cytidylyltransferase, a rate-regulatory enzyme in phosphatidylcholine biosynthesis, and fatty-acid synthase (FAS) are increased in type IIB cells isolated from rats 14 days after silica injection. In the present study, we examined the increase in FAS and cytidylyltransferase activities in type IIB cells as a function of time after silica administration. FAS activity increased rapidly, was approximately threefold elevated 1 day after silica administration and has reached close to the maximum increase by 3 days. Cytidylyltransferase activity was not increased on day 1, was significantly increased on day 3 but was not maximally increased until day 7. Inhibition of de novo fatty-acid biosynthesis, by in vivo injection of hydroxycitric acid and inclusion of agaric acid in the type II cell culture medium, abolished the increase in cytidylyltransferase activity on day 3 but not FAS and had no effect on activities of two other enzymes of phospholipid synthesis. FAS mRNA levels were not increased in type IIB cells isolated 1-14 days after silica injection. These data show that the increase in FAS activity in type IIB cells is an early response to silica, that it mediates the increase in cytidylyltransferase activity, and that it is not due to enhanced FAS gene expression.

scholarly journals Perturbation of β1-Integrin Function in Involuting Mammary Gland Results in Premature Dedifferentiation of Secretory Epithelial Cells

2002 ◽  
Vol 13 (10) ◽  
pp. 3521-3531 ◽  
Author(s):  
Marisa M. Faraldo ◽  
Marie-Ange Deugnier ◽  
Sylvie Tlouzeau ◽  
Jean Paul Thiery ◽  
Marina A. Glukhova
Keyword(s):  
Mammary Gland ◽  
Epithelial Cells ◽  
Nuclear Factor Κb ◽  
Dominant Negative ◽  
Negative Regulator ◽  
Dominant Negative Mutant ◽  
Β1 Integrin ◽  
Mrna Levels ◽  
Pregnancy And Lactation

To study the mechanism of β1-integrin function in vivo, we have generated transgenic mouse expressing a dominant negative mutant of β1-integrin under the control of mouse mammary tumor virus (MMTV) promoter (MMTV-β1-cyto). Mammary glands from MMTV-β1-cyto transgenic females present significant growth defects during pregnancy and lactation and impaired differentiation of secretory epithelial cells at the onset of lactation. We report herein that perturbation of β1-integrin function in involuting mammary gland induced precocious dedifferentiation of the secretory epithelium, as shown by the premature decrease in β-casein and whey acidic protein mRNA levels, accompanied by inactivation of STAT5, a transcription factor essential for mammary gland development and up-regulation of nuclear factor-κB, a negative regulator of STAT5 signaling. This is the first study demonstrating in vivo that cell–extracellular matrix interactions involving β1-integrins play an important role in the control of milk gene transcription and in the maintenance of the mammary epithelial cell differentiated state.

MUSCLE-INDUCED PATELLOFEMORAL JOINT LOADING RAPIDLY AFFECTS CARTILAGE mRNA LEVELS IN A SITE SPECIFIC MANNER

2004 ◽  
Vol 08 (01) ◽  
pp. 1-12 ◽  
Author(s):  
Andrea L. Clark ◽  
Linda Mills ◽  
David A Hart ◽  
Walter Herzog
Keyword(s):  
Articular Cartilage ◽  
Mechanical Loading ◽  
Patellofemoral Joint ◽  
Mrna Level ◽  
Recovery Period ◽  
Cartilage Explants ◽  
Mrna Levels ◽  
Biological Responses

Mechanical loading of articular cartilage affects the synthesis and degradation of matrix macromolecules. Much of the work in this area has involved mechanical loading of articular cartilage explants or cells in vitro and assessing biological responses at the mRNA and protein levels. In this study, we developed a new experimental technique to load an intact patellofemoral joint in vivo using muscle stimulation. The articular cartilages were cyclically loaded for one hour in a repeatable and measurable manner. Cartilage was harvested from central and peripheral regions of the femoral groove and patella, either immediately after loading or after a three hour recovery period. Total RNA was isolated from the articular cartilage and biological responses were assessed on the mRNA level using the reverse transcriptase-polymerase chain reaction. Articular cartilage from intact patellofemoral joints demonstrated heterogeneity at the mRNA level for six of the genes assessed independent of the loading protocol. Cyclical loading of cartilage in its native environment led to alterations in mRNA levels for a subset of molecules when assessed immediately after the loading period. However, the increases in TIMP-1 and decreases in bFGF mRNA levels were transient; being present immediately after load application but not after a three hour recovery period.

scholarly journals Circular RNA hsa_circ_102209 promotes the growth and metastasis of colorectal cancer through miR-761-mediated Ras and Rab interactor 1 signaling

2020 ◽  
Author(s):  
CHI LI ◽  
Hong Zhou
Keyword(s):  
Colorectal Cancer ◽  
Cell Cycle ◽  
Epithelial Cells ◽  
Cell Cycle Arrest ◽  
Quantitative Polymerase Chain Reaction ◽  
Tumor Stage ◽  
Migration And Invasion ◽  
Colonic Epithelial Cells ◽  
Cycle Arrest

Abstract Background: In our study, has_circ_102209 was the most upregulated gene in colorectal cancer (CRC) tissues according to circRNA array data. The levels of hsa_circ_102209 in CRC specimens and cells, as well as its effects on CRC cells were investigated. Methods: The expression of hsa_circ_102209 in CRC and paired non-cancerous samples, human CRC and normal colonic epithelial cells were examined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cells with hsa_circ_102209 knockdown were established using lentiviral vectors . Cell proliferative ability was evaluated using CCK-8 assay; cell migration and invasion were assessed by wound healing and Transwell assay. Cell cycle arrest and apoptosis were determined; apoptosis and EMT markers were examined using RT-qPCR and western blotting. Tumour development and levels of associated proteins were determined in hsa_circ_102209 knockdown mice. Results: Our results revealed that expression of hsa_circ_102209 was remarkably increased in CRC tissues, where the levels of miR-761 were notably reduced (p<0.05). Additionally, the levels of hsa_circ_102209 was associated with tumor stage and occurrence of liver metastasis in CRC patients, and the expression of hsa_circ_102209 and miR-761 were negatively correlated (p<0.05). Moreover, hsa_circ_102209 was upregulated in CRC cell s compared with normal colonic epithelial cells. Knockdown of hsa_circ_102209 notably inhibited the proliferation, migration, invasion and EMT of CRC cell s (p<0.05), whereas enhanced cell cycle arrest at G0/G1 phase and apoptosis (p<0.05). Furthermore, miR-761/ Ras and Rab interactor 1 ( RIN1) axis was the putative target of hsa_circ_102209 in CRC and involved in hsa_circ_102209 -modulated growth and metastasis in CRC cell s (p<0.05). Knockdown of hsa_circ_102209 also remarkably suppressed tumor growth in vivo (p<0.05). Conclusions: our data revealed that the expression of hsa_circ_102209 was elevated in CRC samples and cells. Furthermore, hsa_circ_102209 could promote the progression of CRC through miR-761/RIN1 axis. More importantly, hsa_circ_102209 /miR-761/RIN1 signaling may be a novel therapeutic target for the treatment of CRC patients .

scholarly journals Circular RNA hsa_circ_102209 promotes the growth and metastasis of colorectal cancer through miR-761-mediated Ras and Rab interactor 1 signaling

2020 ◽  
Author(s):  
CHI LI ◽  
Hong Zhou
Keyword(s):  
Colorectal Cancer ◽  
Cell Cycle ◽  
Epithelial Cells ◽  
Cell Cycle Arrest ◽  
Quantitative Polymerase Chain Reaction ◽  
Circular Rna ◽  
Migration And Invasion ◽  
Colonic Epithelial Cells ◽  
Cycle Arrest

Abstract Background: The levels of hsa_circ_102209 in colorectal cancer (CRC) specimens and cells, as well as its effects on CRC cells were investigated. Methods: The expression of hsa_circ_102209 in CRC and paired non-cancerous samples, human CRC and normal colonic epithelial cells were examined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cells with hsa_circ_102209 knockdown were established using lentiviral vectors. Cell proliferative ability was evaluated using CCK-8 assay; cell migration and invasion were assessed by wound healing and Transwell assay. Cell cycle arrest and apoptosis were determined; apoptosis and EMT markers were examined using RT-qPCR and western blotting. Tumour development and levels of associated proteins were determined in hsa_circ_102209 knockdown mice. Results: Our results revealed that expression of hsa_circ_102209 was remarkably increased in CRC tissues, where the levels of miR-761 were notably reduced (p<0.05). Additionally, the levels of hsa_circ_102209 was associated with histology grade and occurrence of liver metastasis in CRC patients, and the expression of hsa_circ_102209 and miR-761 were negatively correlated (p<0.05). Moreover, hsa_circ_102209 was upregulated in CRC cells compared with normal colonic epithelial cells. Knockdown of hsa_circ_102209 notably inhibited the proliferation, migration, invasion and EMT of CRC cells (p<0.05), whereas enhanced cell cycle arrest at G0/G1 phase and apoptosis (p<0.05). Furthermore, miR-761/Ras and Rab interactor 1 (RIN1) axis was the putative target of hsa_circ_102209 in CRC and involved in hsa_circ_102209-modulated growth and metastasis in CRC cells (p<0.05). Knockdown of hsa_circ_102209 also remarkably suppressed tumor growth in vivo (p<0.05). Conclusions: our data revealed that the expression of hsa_circ_102209 was elevated in CRC samples and cells. Furthermore, hsa_circ_102209 could promote the progression of CRC through miR-761/RIN1 axis. More importantly, hsa_circ_102209/miR-761/RIN1 signaling may be a novel therapeutic target for the treatment of CRC patients.

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