Intestinal Trefoil Factor mRNA Research Articles

Growth hormone upregulates intestinal trefoil factor expression in the ileum of rats after γ-radiation

Growth hormone (GH) and intestinal trefoil factor (ITF) have been involved in intestinal protection and repair. This study investigates the effects of GH administration on ITF expression and histological changes associated with tissue injury in an intestinal rat model of radiation. Adult male rats were divided into four groups: control, GH, radiation and radiation + GH (GHyRAD). Ileum samples were obtained at 2 or 72 h after radiation and processed to determine ITF levels (mRNA and protein) by quantitative polymerase chain reaction, Western blot and immunohistochemistry. In addition, goblet ITF-positive cells were identified by immunohistochemistry at 72 h. Our results showed an upregulation of mRNA and protein production of ITF in ileum samples after GH and radiation + GH compared with control and irradiated samples. Irradiation alone affected ITF protein expression. However, irradiation after GH pretreatment produced the highest ITF mRNA and protein levels at both the tested time points. ITF-producing goblet cells were identified in intestinal villi (apical location). GH treatment increased the number of ITF-producing goblet cells, and radiation after GH treatment displayed further increase in the number of ITF-positive goblet cells. GH upregulates ITF in normal intestinal tissue. This upregulation is higher when radiation is given after GH treatment. Nevertheless, the mechanism by which GH regulates ITF expression remains unclear and is still under investigation. These results could open up new avenues in the therapeutic reparative and protective effects of GH during radiotherapy and chemotherapy.

The Effect of EA on the Gastric Mucosal Histology and ITF mRNA Expression in Stress-Induced Rats

This study focuses on the effect of electroacupuncture (EA) on the gastric mucosal histology and ITF (intestinal trefoil factor) mRNA in stress-related rat, and the relationship between the gastric protective mechanism of EA at acupoints of Stomach Meridian of Foot-Yangming (SMFY) group and Gallbladder Meridian of Foot-Shaoyang (GMFS) group. Forty rats were randomly divided into 4 groups: blank control group (BCG), model control group (MCG), SMFY group (EA at acupoints of SMFY for 7 days before model inducing), and GMFS group (EA at acupoints of GMFS for 7 days before model inducing). All rats (except normal group) were made model by water immersion and restriction (WRS) on day 7, then the gastric mucosal lesion index (GUI) was accessed, ITF mRNA expression of the tissue was detected by reverse- transcriptase-polymerase chain reaction (RT-PCR) method, and the histological change under light microscope was observed. As a result, the GUI value in SMFY/GMFS groups decreased significantly (p < 0.05 or 0.01). The level of ITF mRNA expression in SMFY group was significantly higher than that in MCG (p < 0.01), while that in GMFS group was higher than MCG but there was no statistical difference (p < 0.05). This result may be due to the intrinsic mechanism of EA's gastric mucosal protection by the upregulation of ITF mRNA expression in gastric mucosal tissue, and the expression variance indicated the classical traditional Chinese medicine (TCM) theory "Relative Particularity between SMFY and Stomach.".

Effect of electroacupunture on gastric mucosal intestinal trefoil factor gene expression of stress-induced gastric mucosal injury in rats

To investigate electroacupuncture(EA) at the acupoints of Stomach Meridian of Foot-Yangming (SMFY), Gallbladder Meridian of Foot-Yangming (SMFY) on gastric mucosal intestinal trefoil factor (ITF) gene expression detection in stress-induced rats with gastric mucosal lesion, and to explore the regulatory mechanism and significance of EA-related gastric mucosal protective effect. Forty rats were randomly divided into 4 groups: Blank group, Model group, Model group+EA at acupoints of SMFY group ("SMFY group"), and Model group+EA at acupoints of GMFY group(GMFY group). All rats (except blank group) were made model by water immersion and restraint stress (WRS). Then the gastric mucosa tissue in each rat was taken off after assessment of gastric mucosal lesion index(GUI), and the expression of ITF mRNA of the tissues was detected by reverse transcription-polymerase chain reaction (RT-PCR) method. Compared with Model group(54.3+/- 1.34), the GUI value in SMFY group (31+/- 2.21) decreased significantly(P< 0.01), so did that in GMFY group (39.8+/- 1.62, P< 0.05), meanwhile GUI value in SMFY group was significantly lower than in GMFY group(P< 0.01). Compared with Model group (0.65+/- 0.01), EA had a tendency to improve the expression of gastric mucosal ITFmRNA gene: such tendency existed in GMFY group (0.66+/- 0.01) but with no significant difference(P>0.05), in SMFY group(0.76+/- 0.01) with an extremely obvious difference (P< 0.01), furthermore the expression in SMFY group was significantly higher than in GMFY group (P< 0.01). The gastric mucosal protective effect by EA at the acupoints of SMFY and GMFY was related to the expression variance of ITF, indicating certain meridian specificity exists. It could be one proof for the TCM theory "Relative particularity between SMFY and stomach".

Expression of intestinal trefoil factor, proliferating cell nuclear antigen and histological changes in intestine of rats after intrauterine asphyxia

To study the expressions of intestinal trefoil factor (ITF) and proliferating cell nuclear antigen (PCNA) and histologic changes in intestine, to investigate the relationship between ITF and intestinal damage and repair after intrauterine hypoxia so as to understand the mechanism of intestinal injury and to find a new way to prevent and treat gastrointestinal diseases. Wistar rats, pregnant for 21 d, were used to establish animal models of intrauterine asphyxia by clamping one side of vessels supplying blood to uterus for 20 min, another side was regarded as sham operation group. Intestinal tissues were taken away at 0, 24, 48 and 72 h after birth and stored in different styles. ITF mRNA was detected by RT-PCR. PCNA expression was measured by immunohistochemistry. Intestinal tissues were studied histologically by HE staining in order to observe the areas and degree of injury and to value the intestinal mucosa injury index (IMDI). ITF mRNA appeared in full-term rats and increased with age. After ischemia, ITF mRNA was decreased to the minimum (0.59+/-0.032) 24 h after birth, then began to increase higher after 72 h than it was in the control group (P<0.01). PCNA positive staining located in goblet cell nuclei. The PCNA level had a remarkable decline (53.29+/-1.97) 48 h after ischemia. Structure changes were obvious in 48-h group, IMDI (3.40+/-0.16) was significantly increased. Correlation analyses showed that IMDI had a negative correlation with ITF mRNA and PCNA (r = -0.543, P<0.05; r = -0.794, P<0.01, respectively). Intrauterine ischemia can result in an early decrease of ITF mRNA expression. ITF and PCNA may play an important role in the damage and repair of intestinal mucosa.

Hypoxia-inducible factor 1-dependent induction of intestinal trefoil factor protects barrier function during hypoxia.

Mucosal organs such as the intestine are supported by a rich and complex underlying vasculature. For this reason, the intestine, and particularly barrier-protective epithelial cells, are susceptible to damage related to diminished blood flow and concomitant tissue hypoxia. We sought to identify compensatory mechanisms that protect epithelial barrier during episodes of intestinal hypoxia. Initial studies examining T84 colonic epithelial cells revealed that barrier function is uniquely resistant to changes elicited by hypoxia. A search for intestinal-specific, barrier-protective factors revealed that the human intestinal trefoil factor (ITF) gene promoter bears a previously unappreciated binding site for hypoxia-inducible factor (HIF)-1. Hypoxia resulted in parallel induction of ITF mRNA and protein. Electrophoretic mobility shift assay analysis using ITF-specific, HIF-1 consensus motifs resulted in a hypoxia-inducible DNA binding activity, and loading cells with antisense oligonucleotides directed against the alpha chain of HIF-1 resulted in a loss of ITF hypoxia inducibility. Moreover, addition of anti-ITF antibody resulted in a loss of barrier function in epithelial cells exposed to hypoxia, and the addition of recombinant human ITF to vascular endothelial cells partially protected endothelial cells from hypoxia-elicited barrier disruption. Extensions of these studies in vivo revealed prominent hypoxia-elicited increases in intestinal permeability in ITF null mice. HIF-1-dependent induction of ITF may provide an adaptive link for maintenance of barrier function during hypoxia.

Augmented Intestinal Trefoil Factor (TFF3) and Loss of pS2 (TFF1) Expression Precedes Metaplastic Differentiation of Gastric Epithelium

The trefoil peptides spasmolytic polypeptide (SP), intestinal trefoil factor (ITF), and pS2 show lineage-specific expression in the normal gut and are strongly induced after mucosal injury. We assessed the relationship between this induction and the development of the regenerative epithelial lineage over time in the rat stomach and verified these observations in the metaplastic and dysplastic human stomach. Antral or colonic ulcers were induced in Wistar rats by application of serosal acetic acid and tissues harvested 2 hours to 125 days later. Human endoscopic biopsies or gastric resection specimens were also assessed. Tissues were examined by radioimmunoassay, immunoblotting, or immunohistochemistry for ITF, SP, and transforming growth factor α (rat) or ITF and pS2 (human) expression. ITF and SP mRNA in antral ulcer margins was localized by in situ hybridization. ITF and SP peptide expression rose steadily in ulcer margins after 4 days, with the rise in ITF being more pronounced. By 40 days, several hundred-fold elevations in ITF levels were present, with a field effect in uninvolved mucosa. Hyperproliferative, elongated glands of undifferentiated cells expressing abundant trefoil peptides and acid sulfomucins were present after day 12 and persisted after ulcer healing. ITF mRNA was aberrantly expressed in basal and mid-regions of these regenerative glands. In contrast, transforming growth factor α peptide expression rose promptly after injury then fell to baseline levels with healing. Seven months after injury, gastric atrophy, intestinal metaplasia, and severe dysplasia with conserved ITF expression were seen. ITF was also induced in human intestinal metaplasia and conserved in all gastric cancers, whereas expression of the gastric peptide pS2 was progressively reduced in the progression from metaplasia to dysplasia. Persistent, selective overexpression of ITF, possibly acting in an autocrine fashion, is a feature of regeneration after antral ulceration, and may provide insight into the nature of metaplastic phenotypes arising from chronic gastric injury. The loss of pS2 expression in metaplasia and cancer supports a role for this protein in gastric tumor suppression.

Quantitative analysis reveals differential expression of mucin (MUC2) and intestinal trefoil factor mRNAs along the longitudinal axis of rat intestine

MUC2 and intestinal trefoil factor (ITF) are considered to have important roles in intestinal mucosal protection and epithelial repair. In order to investigate whether these genes are co-ordinately expressed, we have used competitive reverse transcription-polymerase chain reaction assays to measure MUC2 and ITF mRNA levels in human intestinal cell lines and along the longitudinal axis of rat intestine. ITF mRNA was expressed in several intestinal cell lines. However, MUC2 mRNA was detected only in LS174T cells where it was present at approx. 25-fold lower levels than the ITF transcript. In contrast, in rat intestinal tissues, MUC2 mRNA levels were generally higher than ITF mRNA levels. The levels of both transcripts increased markedly during postnatal development. In adult rats, the expression patterns of MUC2 and ITF mRNAs along the longitudinal axis of the small intestine were similar, with lowest levels in the proximal duodenum and relatively constant levels in the other regions assayed. In contrast, the expression patterns of MUC2 and ITF in different regions of the large intestine showed a marked divergence. Our results strongly suggest that expression of the MUC2 and ITF genes is not co-ordinately regulated in intestinal cells.

O.01 Regulation of intestinal trefoil factor mRNA by nutritional status and keratinocyte growth factor

O.01 Regulation of intestinal trefoil factor mRNA by nutritional status and keratinocyte growth factor

Short-chain fatty acids inhibit intestinal trefoil factor gene expression in colon cancer cells.

Intestinal trefoil factor (ITF) gene expression was detected in five colon cancer cell lines. ITF was synthesized by mucous cells of LIM 1215 and LIM 1863 lines, from which it is secreted constitutively. The ITF mRNA transcript was estimated to be 0.6 kb. In LIM 1215 cells, the expression of ITF was potently and dose-dependently inhibited by short-chain fatty acids (butyrate > propionate > acetate) within 8 h of application. The inhibitory effect of butyrate was ablated by actinomycin D and preceded its effects on differentiation of LIM 1215 cells as indicated by induction of alkaline phosphatase activity and counting of periodic acid-Schiff-positive cells. The human ITF promoter contained an 11-residue consensus sequence with high homology to the butyrate response element of the cyclin D1 gene. Mobility shift assays show specific binding of this response element to nuclear protein extracts of LIM 1215 cells. We conclude that butyrate inhibits ITF expression in colon cancer cells and that this effect may be mediated transcriptionally and independently of its effects on differentiation.

Expression of intestinal trefoil factor mRNA is downregulated during progression of colorectal carcinomas.

AIMS: Intestinal trefoil factor is a mucosa associated trefoil peptide expressed predominantly in the goblet cells of the small and large intestine. The aim of this work was to investigate...

Localization of intestinal trefoil-factor mRNA in rat stomach and intestine by hybridization in situ.

A cDNA encoding rat intestinal trefoil factor (rITF) was prepared by reverse transcription and PCR amplification. The sequence obtained was well conserved with that of other trefoil peptides. An antisense riboprobe produced from the clone was used to localize the sites of ITF expression in the rat gastrointestinal tract using hybridization in situ. We found rITF mRNA in goblet cells in the small intestine and colon; a gradient of signal strength greatest near the crypt base was sometimes present. We found no evidence for rITF expression in Brunner's glands, the pancreas, or most regions of the gastric mucosa. Surprisingly, strong signals for rITF mRNA were detected in a region of stomach at the junction of the squamous fore-stomach with the glandular gastric mucosa. This region, which may correspond to the cardiac region, formed part of a larger area of cells staining positive for acid mucins. We hypothesize that concerted expression occurs of particular trefoil peptides with specific mucins, and that this organization reflects a functional relationship between mucins and trefoil peptides.