Serotonin and neuroendocrine peptides influence DNA synthesis in rat and human small intestinal cells 						in vitro

Zachrisson,; Uribe,

doi:10.1046/j.1365-201x.1998.00328.x

Cited by 16 publications

(8 citation statements)

References 32 publications

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“…IEC-6 cells are nontransformed small intestinal epithelial cells that retain receptors to growth factors [42]and possess cell kinetics characteristics that resemble those of human antral epithelial cells [43, 44]. It is noteworthy that the vast majority of the cells used in our study were viable, as shown by trypan blue exclusion and by the flow cytometric analysis with propidium iodide/annexin-V staining (fig.…”

Section: Discussionmentioning

confidence: 87%

40- to 100-kD Protein(s) of Helicobacter pylori Stimulate DNA Synthesis in Epithelial Cell Lines without Affecting Apoptosis

Neopikhanov¹,

Samali²,

Wreiber³

et al. 2000

Digestion

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Background: Previous in vitro studies have demonstrated that water extracts and sonicates of Helicobacter pylori increase DNA synthesis in a small intestinal epithelial cell line. The aim of this study was to identify mitogenic factor(s) in a water extract of a H. pylori strain and to examine their effects on DNA synthesis and apoptosis in vitro. Methods: IEC-6 and FHs 74 cells were incubated for 24 h with different dilutions of a water extract of H. pylori (cytotoxic strain 88–23) or with 6 protein fractions obtained by gel filtration. Cells were labeled with tritiated thymidine and processed for autoradiography. DNA synthesis was evaluated by the labeling index (LI%). The proportion of IEC-6 cells undergoing apoptosis and/or necrosis was evaluated by flow cytometry using fluorescein isothiocyanate (FITC)-labeled annexin-V and propidium iodide. In vitro caspase activity was also determined as an alternative method for detection of apoptosis. Results: The water extract of H. pylori 88-23 markedly increased DNA synthesis in both epithelial cell lines (p < 0.01). A marked stimulation of DNA synthesis was also observed in IEC-6 cells incubated with fraction II- containing proteins of a molecular weight ranging between 40 and 100 kD (p < 0.01). A lesser stimulation of DNA synthesis was observed in cells incubated with higher concentrations of the other protein fractions (p < 0.01). Neither the water extract of H. pylori 88-23 nor the protein fraction II (40–100 kD) induced apoptosis in IEC-6 cells. Conclusion: A water extract of H. pylori 88-23 and a protein fraction containing proteins with molecular weights of 40–100 kD stimulate DNA synthesis in a rat and human small intestinal cell line. Apoptosis was unaffected by the water extract and by protein fraction II, which indicate that the H. pylori-derived mitogen(s) have the capacity to directly enhance epithelial cell proliferation in vitro.

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Section: Discussionmentioning

confidence: 87%

40- to 100-kD Protein(s) of Helicobacter pylori Stimulate DNA Synthesis in Epithelial Cell Lines without Affecting Apoptosis

Neopikhanov¹,

Samali²,

Wreiber³

et al. 2000

Digestion

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“…Adding to that, experiments using co-cultures indicate that human submucosal neurons might control the intestinal epithelium, since disorganization and proliferation occured in the absence of neuronal activation (Toumi et al 2003). Serotonin, in contrast to other factors, inhibits intestinal cell proliferation in vitro (Zachrisson & Uribe 1998). Our results indicate that serotonin cell population is diminished after myenteric ablation, and this response is concomitant with the enlargement of submucous VIP neurons (Hernandes et al, 2004).…”

Section: Discussionmentioning

confidence: 68%

“…Enteroendocrine cells are characterized by the presence of numerous granules that contain chemical mediators, which are active on the secretory, absorptive and motor functions (Ormsbee & Fondacaro 1985). Although the mediators have been identified (Sjo´lund et al 1983), the main product of these cells is serotonin (Inokuchi et al 1983, Hocker & Wiedenmann 1998, which was shown to inhibit the proliferation of intestinal cells in vitro (Zachrisson & Uribe 1998).…”

Section: Introductionmentioning

confidence: 99%

Myenteric denervation differentially reduces enteroendocrine serotonin cell population in rats during postnatal development

Hernandes

Fernandes²,

Pereira

et al. 2006

J Mol Hist

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The enteric nervous and enteroendocrine systems regulate different processes in the small intestine. Ablation of myenteric plexus with benzalkonium chloride (BAC) stimulates epithelial cell proliferation, whereas endocrine serotonin cells may inhibit the process. To evaluate the connection between the systems and the influence of myenteric plexus on serotoninergic cells in rats during postnatal development, the ileal plexus was partially removed with BAC. Rats were treated at 13 or 21 days and sacrificed after 15 days. The cell bodies of myenteric neurons were stained by beta NADH-diaphorase to detect the extension of denervation. The number of enteroendocrine cells in the ileum was estimated in crypts and villi in paraffin sections immunostained for serotonin. The number of neurons was reduced by 27.6 and 45% in rats treated on the 13th and 21st days, respectively. We tried to establish a correlation of denervation and the serotonin population according to the age of treatment. We observed a reduction of immunolabelled cells in the crypts of rats treated at 13 days, whereas this effect was seen in the villi of rats denervated at 21 days. These results suggest that the enteric nervous system might control the enteroendocrine cell population and this complex mechanism could be correlated to changes in cell proliferation.

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“…Intraluminal bacteria modulate the endocrine cell system and the synthesis or release of neuroendocrine peptides (8) with known mitogenic actions on epithelial cells (9,10). In addition, bacteria and bacterial-derived antigens in uence immune and other intestinal mucosa cells and modulate the production of cytokines (10) which are potent stimulators of DNA synthesis in lymphocytes (11,12) and other cell types, including intestinal epithelial cells (4).…”

Section: Introductionmentioning

confidence: 99%

“…In addition, bacteria and bacterial-derived antigens in uence immune and other intestinal mucosa cells and modulate the production of cytokines (10) which are potent stimulators of DNA synthesis in lymphocytes (11,12) and other cell types, including intestinal epithelial cells (4). Moreover, bacteria possess mitogens that can directly stimulate DNA synthesis of epithelial cell lines in ×itro (6).…”

Section: Introductionmentioning

confidence: 99%

Bacterial Wall Components such as Lipothecoid Acid, Peptidoglycan, Liposaccharide and Lipid A Stimulate Cell Proliferation in Intestinal Epithelial Cells

Olaya¹

2001

Microbial Ecology in Health and Disease

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Earlier studies indicate that the micro ora contains mitogens to intestinal epithelial cells. Our aim is to examine whether cell wall components of both Gram-negative and positive bacteria in uence cell proliferation in small intestinal and colonic epithelial cells. A human colonic epithelial cell line from adenocarcinoma (IEC-6) and a nontransformed small intestinal cell line from germ-free rats (LS-123) were incubated with (a) lipothecoid acid from Streptococcus faecalis at 1.56 -50 mg:ml, (b) peptidoglycan from Staphylococcus aureus at 0.1 -7.5 mg:ml, (c) lipopolysaccharides (LPS) from Escherichia coli, Klebsiella pneumonia and Pseudomona aeruginosa at 0.1 -7.5 m g:ml, (d) lipid A from Escherichia coli at 0.016 -50 m g:ml. The cells were labelled with tritiated thymidine and processed for autoradiography. DNA synthesis was estimated by the labelling index.Cell wall components of Gram-positive bacteria (LTA from Streptococcus faecalis and peptidoglycan from Staphylococcus aureus) moderately increased the DNA synthesis in both cell lines (p B0.001). Similarly, cell wall components of Gram-negative bacteria (LPS of Escherichia coli, Klebsiella pneumonia and Pseudomona aeruginosa and lipid A of Escherichia coli increased the labelling index in IEC-6 and LS-123 cells (p B0.001).Thus, this study identi es mitogens present in both Gram-positive and Gram-negative bacteria that increase cell proliferation in rat and human intestinal cells. Our ndings support a role for the micro ora in the regulation of cell proliferation in both health and disease.

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Serotonin and neuroendocrine peptides influence DNA synthesis in rat and human small intestinal cells in vitro

Cited by 16 publications

References 32 publications

40- to 100-kD Protein(s) of <i>Helicobacter pylori</i> Stimulate DNA Synthesis in Epithelial Cell Lines without Affecting Apoptosis

40- to 100-kD Protein(s) of <i>Helicobacter pylori</i> Stimulate DNA Synthesis in Epithelial Cell Lines without Affecting Apoptosis

Myenteric denervation differentially reduces enteroendocrine serotonin cell population in rats during postnatal development

Bacterial Wall Components such as Lipothecoid Acid, Peptidoglycan, Liposaccharide and Lipid A Stimulate Cell Proliferation in Intestinal Epithelial Cells

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