Effects Of Intestinal Trefoil Factor Research Articles

Intestinal Trefoil Factor 3 Alleviates the Intestinal Barrier Function Through Reducing the Expression of TLR4 in Rats with Nonalcoholic Steatohepatitis

Previous studies have reported that nonalcoholic steatohepatitis (NASH) is relevant to intestinal mucosal barrier dysfunction. To investigate the effects of intestinal trefoil factor 3 (TFF3) on intestinal barrier function and endotoxin/toll-like receptor 4(TLR4) expression in NASH rats. Sixty NASH rats were divided into control, NASH and NASH-TFF3 treated group. Intestinal permeability, serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), endotoxin (ET), diamine oxidase (DAO) and liver index were examined. HE and PAS staining were performed to observe the histopathology of liver and terminal ileum. Expression of TFF3 and occludin were detected by immunohistochemical staining. mRNA and protein expression of TLR4, nuclear factor-κB (NF-κB), Mucin-2(Muc2) were detected by RT-qPCR and Western Blot. Interleukin (IL) -1β and IL-10 levels in the ileum were measured by ELISA. In NASH group, levels of AST, ALT, ET, DAO, NAS, liver index and intestinal permeability were higher while occludin expressions were lower than control and NASH-TFF3 treated groups (p <0.05). Histopathology examination showed pathological damages of liver and ileum were alleviated in NASH-TFF3 treated group. NASH-TFF3 treated group had decreased expression levels of TLR4 and NF-κB and increased expression levels of Muc2 than NASH group. Besides, NASH group showed increased IL-1β and IL-10 levels compared with control group. NASH-TFF3 treated group showed decreased IL-1β level however increased IL-10 level compared with NASH group. Recombinant human TFF3 (rhTFF3) can reduce the expression of TLR4, reduce intestinal permeability, alleviate liver damage and thus may play a therapeutic role in the treatment of NASH rats.

Protective Effects of Intestinal Trefoil Factor against Endotoxin-Induced Injury of Intestinal Mucosal Epithelial Cells in Piglets

Protective Effects of Intestinal Trefoil Factor against Endotoxin-Induced Injury of Intestinal Mucosal Epithelial Cells in Piglets

Intestinal trefoil factor increased the Bcl-2 level in a necrotizingenterocolitis neonate rat model.

The aim of this study was to investigate the therapeutic effect of intestinal trefoil factor (ITF) on necrotizing enterocolitis (NEC) by observing the pathological changes and detecting the protein level differences in Caspase-3, Bax, and Bcl-2 in an NEC neonate rat model. A Wistar rat model of NEC was established and 30 one-day-old neonate Wistar rats were randomly divided into three groups including a normal control (group A), NEC rats treated with 0.2 ml physiological saline through intraperitoneal (i.p.) injection (group B), and NEC rats treated with 0.2 mg ITF by i.p injection (group C). Compared with group B, there were statistically significant differences in Caspase-3, Bax, and Bcl-2 levels in groups A and C(P < 0.05). Moreover, there was a significant difference in the Bcl-2 level between groups A and B (P < 0.05). ITF alleviated injury of the intestinal tract in neonate rats with NEC and this mechanism was possibly related to a reduction in the expression of Caspase-3 and Bax and the increase in Bcl-2 expression.

Protective effects of intestinal trefoil factor (ITF) on gastric mucosal epithelium through activation of extracellular signal-regulated kinase 1/2 (ERK1/2).

The rapid repair of gastric mucosa is critical upon exposure to injurious agents. Intestinal trefoil factor (ITF) is a member of the trefoil factor family domain peptides, which play an important role in the cytoprotection of gastric epithelium. However, the underlying molecular mechanisms that are responsible for ITF-induced gastric epithelial repair remain unclear. In the present study, we demonstrate that ITF enhances the proliferation and migration of GES-1 gastric endothelial cells in a dose- and time-dependent manner through the activation of extracellular signal-regulated kinase 1/2 (ERK1/2). Furthermore, the ITF-mediated protection of GES-1 cells from a NS398 (nonsteroidal anti-inflammatory drug) was dependent on the ERK1/2 signaling pathway. Taken together, the results provide a mechanistic explanation for ITF-mediated protection of gastric epithelial mucosa cells, suggesting that activation of the ERK1/2 signaling pathway may provide a new therapeutic strategy for repairing gastric injury.

Relationship of intestinal trefoil factor for regulating of nuclear factor-κB and tumor necrosis factor-α and the protective effect of intestinal injury

Objective To investigate the relationship of intestinal trefoil factor(ITF) for regulating of nuclear factor(NF)-κB and tumor necrosis factor(TNF)-α and the protective effect of intestinal injury. Methods Twenty-four 10-day Wistar rats were divided into 3 groups: the control group(NS group, n=8), given 9 g/L sodium injection intra-peritoneally, 1 mL/kg; the lipopolysaccharide(LPS) group(n=8), given LPS(5 g/L), 5 mg/kg intraperitoreally; ITF group(n=8), given ITF(5 g/L) 0.1 mL/each plus LPS 5 mg/kg intraperitoreally.Rats were sacrificed 3 hours after injection.A segment of distal ileum was dissected.The pathologic changes of small intestine were observed under the optical microscope(hematoxylin-eosin staining). The expressions of NF-κB mRNA and protein were detected by reverse transcription polymerase chain reaction(RT-PCR), immunohistochemistry, respectively.TNF-α level in intestinal tissues was measured by enzyme linked immunosorbent assay. Results The structure of small intestine in the control group remained normal.The inflammatory cells infiltration and the edema of interstitial substance and epithelium were observed in LPS group and ITF group, while the change in the ITF group was significantly lower than that in LPS group.The expressions of NF-κB mRNA and protein in ITF group were significantly lower than those in LPS group(all P<0.01). The secretion of TNF-α in the ITF group was significantly lower than that in LPS group(P<0.01). Conclusion Protective effects of ITF on intestinal injury are related to the down regulation of NF-κB mRNA and protein expressions and the reduction of the secrete of mediators of inflammation TNF-α. Key words: Intestinal trefoil factor; Nuclear factor-κB; Tumor necrosis factor-α; Intestine

Protective Effect of Intestinal Trefoil Factor on Injury of Intestinal Epithelial Tight Junction Induced by Platelet Activating Factor

Intestinal barrier dysfunction plays an important role in the pathogenesis of inflammatory bowel disease (IBD). To evaluate the effect of intestinal trefoil factor (ITF) on increased intestinal permeability and its association with tight junction proteins, an in vitro intestinal epithelia barrier model was established with Caco-2 cells and treated with platelet-activating factor (PAF). We found that exposing cells to 0.3 M ITF (30 min before or 30 min after PAF treatment) attenuated the PAF-induced changes in transepithelial electrical resistance and Lucifer yellow flux. A quantitative RT-PCR and western blot analysis revealed that ITF suppressed PAF-induced downregulation of tight junction proteins claudin-1 and ZO-1 expression; furthermore, an abnormal localization and distribution of these proteins was inhibited, as assessed by immunofluorescence staining. These results suggest that ITF decreases mucosal permeability and shows potential as a therapy for treating IBD.

Protective effect of intestinal trefoil factor on methotrexate-induced injury in intestinal mucosa

Objective To investigate the potential mechanism of intestinal trefoil factor(ITF)against methotrexate (MTX)- induced injury in intestinal mucosa. Methods Cultured IEC-6 cells were divided into groups as follows: blank group, MTX treated group, ITF treated group and experimental group treated with gradient concentrations of ITF plus MTX. Expression of E-cadherin mRNA was determined by Real-Time polymerase chain reaciton (RT- PCR). The activity of matrix metalloproteinase(MMP)-2 and MMP-9 was measured by gelatin zymogramphy. Caspases-3 activity was measured by colorimetric assay. Cell proliferation was assessed by cell counting kit-8 (CCK-8)assay. Migration of IEC-6 in vitro was observed using modified Boyden chamber assay. Results The expression of E-cadherin mRNA in experimental group (treated with 0.1 mg/ml or 1 mg/ml of ITF) was significantly down-regulated (0. 538±0. 109 or 0. 528±0. 132, respectively) in comparison with MTX treated group (0. 763±0. 139) with significant difference (P=0. 021 or P=0. 025, respectively). There was no significant difference in activity of MMP-2 and MMP-9 among groups (P＞0. 05). When compared with MTX treated group (0. 090 ±0. 011 ), the activity of Caspase3 in experimental group (treated with 0. 1 mg/ml or 1 mg/ml of ITF) was significantly decreased (0. 077±0. 009, P=0. 032 or 0. 044±0. 009,P=0. 005, respectively). There was no statistical difference in cell proliferation between experimental group (treated with 1 μg/ml, 0.01 mg/ml, 0. 1 mg/ml or 1.0 mg/ml of ITF) and MTX treated group (P=0. 132,0. 150,0. 114 or 0. 367, respectivley). More migratory cells attached to the bottom surface of the membrane in experiment group (treated with 0. 1 mg/ml or 1 mg/ml of ITF) in comparison with MTX treated group (P ＜0. 001 ). Moreover, more migratory cells were found in experimental group treated with 1.0 mg/ml of ITF than those in group treated with 0. 1 mg/ml of ITF (P＜0. 001). Conclusions Without cell proliferation, the protective effect of ITF is related to its functions of promoting cell migration and inhibiting cell apoptosis, which may down-regulate expression of E-cadherin mRNA. Key words: Methotrexate; Intestinal trefoil factor; Migration; Apoptosis; E-cadherin

Disruption of the F-actin cytoskeleton and monolayer barrier integrity induced by PAF and the protective effect of ITF on intestinal epithelium

To explore whether platelet-activating factor (PAF) can disrupt the intestinal epithelial barrier directly and is associated with structural alterations of the F-actin-based cytoskeleton, and to observe the protective effect of intestinal trefoil factor (ITF), we establish an intestinal epithelia barrier model using Caco-2 cells in vitro. Transepithelial electrical resistance and unidirectional flux of lucifer yellow were measured to evaluate barrier permeability; immunofluorescent staining and flow cytometry were applied to observe morphological alterations and to quantify proteins of the F-actin cytoskeleton: the tight junction marker ZO-1 and Claudin-1 were observed using immunofluorescent staining. PAF significantly increased paracellular permeability, at the same time, F-actin and tight junction proteins were disrupted. It was thought that ITF could reverse the high permeability by restoring normal F-actin, ZO-1 and Claudin-1 structures. These results collectively demonstrated that PAF plays an important role in the regulation of mucosal permeability and the effects of PAF are correlated with structural alterations of the F-actin-based cytoskeleton and of tight junctions. ITF can protect intestinal epithelium against PAF-induced disruption by restricting the rearrangement of the F-actin cytoskeleton and of tight junctions.

Effects of intestinal trefoil factor on PI3K and caspase-3/9 in newborn rats with necrotizing enterocolitis

PI3K/Akt signal pathway was blocked by Wortmannin, a specific inhibitor of phosphoinositide-3 kinase (PI3K), and the effects of intestinal trefoil factor (ITF) on PI3K and caspase-3/9 in newborn rats with necrotizing enterocolitis (NEC) were investigated to explore the protective mechanism of ITF against NEC. Experimental NEC was induced by exposure to hypoxia for 60 sec followed by cold stress at 4°C for 10 min. A total of 50 One-day-old Wistar rats were randomly divided into five groups : group A, NEC+NS; group B, NEC+ITF; group C,NEC+ wortmannin; group D ,NEC+ wortmannin + ITF; group E , Normal control. The animals were euthanized at development of NEC, and at 96 h the intestinal tissue was harvested and examined for histological changes of NEC, and then the PI3K content and Caspase-3/9 activity were detected using ELISA and spectrophotometry, respectively. The PI3K content (pg/ml) in group A was slightly higher than group E (P 0.05), but the PI3K content (pg/ml) in group B was significantly higher than the remaining groups (P<0.01), and the PI3K content (pg/ml) in group C was significantly lower compared with group E (P<0.01). Compared with group B and E, Caspase-3/9 activity was significantly higher in group A than in group B and E (P<0.01), but all lower than that in group C. So we concluded that ITF could activate the PI3K/Akt pathway to down-regulate Caspase-3/9 activity, and to protect against intestinal damage of NEC rats. Key words: Intestinal trefoil factor, necrotizing enterocolitis, PI3K/Akt signal transduction, Caspase-9, Caspase-3.

Effect of platelet-activating factor on tight junction in intestinal epithelial cells and protective effect of intestinal trefoil factor

Effect of platelet-activating factor on tight junction in intestinal epithelial cells and protective effect of intestinal trefoil factor

Effect of intestinal trefoil factor on expression of iNOS, TNF-α and NO in neonatal rat model of necrotizing enterocolitis

目的 探讨肠三叶因子(intestinal trefoil factor,ITF)对坏死性小肠结肠炎(necrotizingenterocolitis,NEC)新生大鼠的肠黏膜组织中iNOS、TNF-α、NO的含量的影响,及ITF对NEC是否具有保护作用.方法建立NEC模型,对新生1日龄Wistar大鼠予100%二氧化碳,5 min后再予以100%氧气,5 min后放回母鼠身边喂养,第4天处死,取肠组织待检.新生鼠40只随机分为五组,每组8只,A组为NEC模型后予以腹腔注射ITF 0.5 mg;B组为NEC模型后予以皮下注射ITF 0.2mg C、D组为NEC模型后予以腹腔注射生理盐水分别为0.5 ml和0.2 ml;E组为正常对照组.取近回盲部1～2cm肠道组织固定包埋、切片、HE染色做病理学检查及免疫组化观察iNOS的表达,其他肠道组织制备组织匀浆取上清液检测TNF-α、NO的含量.结果A、B及E组iNOS呈弱阳性表达,C、D组iNOS呈强阳性表达;A、B组组织匀浆中TNF-α的含量各为[(30.515±2.731)和(32.229±4.978)pg/mg·pro]均较C、D组[(39.957±8.283)、(39.960±8.374)pg/mg·pro]明显下降(P＜0.01),与E组[(33.523±6.752)pg/mg·pro]差异无统计学意义(P＞0.05);A、B组组织匀浆中NO的含量各为[(0.37±0.07)和(0.54±0.08)μmol/mg tissue]较C、D组[(0.76±0.01)和(0.82±0.04)μmol/mg tissue]明显下降(P＜0.01),与E组[(0.41±0.02)μmol/mg tissue]差异无统计学意义(P＞0.05);A、B组间及C、D组间TNF-α、NO含量差异无统计学意义(P＞0.05);病理切片显示C、D组HE染色切片见肠壁损伤轻重不一,可见全肠黏膜绒毛坏死,病理评分的中位积分为3分;A、B组肠上皮细胞少量脱落,顶端绒毛坏死,病理评分的中位积分为1分.结论通过腹腔和皮下注射ITF可以减轻NEC后的肠道炎症反应,ITF有可能为治疗NEC提供新的方法。

Effects of intestinal trefoil factor on colonic mucosa in experimental colitis of rats

In order to investigate the protective effects of intestinal trefoil factor (ITF) on colonic mucosa in experimental colitis of rats, ITF was detected by RT-PCR and immunohistochemistry at different time points. Three days after colitis induction, rats were treated with either 0.9% saline solution or rhITF. Pathological changes and the expression of iNOS mRNA, NO, MDA and SOD were measured respectively. It was found that ITF was mainly located in goblet cells, significantly higher in model group than in normal group (P<0.05). rhITF could increase the iNOS mRNA expression and NO contents, and there was statistically significant difference between rhITF group and model group (P<0.05). rhITF also caused an increase of MDA and a decrease of SOD, but there was no significant difference between two groups. These results indicated that ITF has apparent therapeutic effects in ulcerative colitis, which may be associated with iNOS and NO.

Chemotherapy- and radiotherapy-induced intestinal damage is regulated by intestinal trefoil factor

Background & Aims : Injury to the intestinal mucosa is frequently a dose-limiting complication of radiotherapy and chemotherapy. Approaches to limit the damage to the intestine during radiation and chemotherapy have been largely ineffective. Trefoil factors are produced throughout the gastrointestinal tract and regulate cell migration, restitution, and repair. Studies were undertaken to define the role of intestinal trefoil factor in modulating the intestinal response to chemotherapy and radiation. Methods : The effect of intestinal trefoil factor on migration and cell survival in intestinal epithelial monolayer exposed to methotrexate was studied in vitro. Chemotherapy and radiation damage was assessed in wild-type and intestinal trefoil factor-null mice in the presence or absence of supplemental intestinal trefoil factor administered in drinking water. Results : Radiation and chemotherapy induced a marked reduction in goblet cell number and intestinal trefoil factor messenger RNA, as well as intestinal trefoil factor promoter activity. Intestinal trefoil factor improved intestinal epithelial cell viability and wound repair after chemotherapy exposure in vitro. Intestinal trefoil factor-deficient mice (intestinal trefoil factor −/−) were more susceptible to chemotherapy- and radiation-induced mucositis. Oral recombinant intestinal trefoil factor reduced the severity of both chemotherapy-induced and chemotherapy/radiotherapy-induced intestinal mucositis. Conclusions : These studies suggest that intestinal trefoil factor is involved in protection against and recovery from intestinal mucositis induced by radiation and chemotherapy.

Trefoil Peptides Promote Restitution of Wounded Corneal Epithelial Cells

The ocular surface shares many characteristics with mucosal surfaces. In both, healing is regulated by peptide growth factors, cytokines, and extracellular matrix proteins. However, these factors are not sufficient to ensure most rapid healing. Trefoil peptides are abundantly expressed epithelial cell products which exert protective effects and are key regulators of gastrointestinal epithelial restitution, the critical early phase of cell migration after mucosal injury. To assess the role of trefoil peptides in corneal epithelial wound healing, the effects of intestinal trefoil factor (ITF/TFF3) and spasmolytic polypeptide (SP/TFF2) on migration and proliferation of corneal epithelial cells were analyzed. Both ITF and SP enhanced restitution of primary rabbit corneal epithelial cells in vitro. While the restitution-enhancing effects of TGF-α and TGF-β were both inhibited by neutralizing anti-TGF-β-antibodies, trefoil peptide stimulation of restitution was not. Neither trefoil peptide significantly affected proliferation of primary corneal epithelial cells. ITF but not SP or pS2 mRNA was present in rabbit corneal and conjunctival tissues. In summary, the data indicate an unanticipated role of trefoil peptides in healing of ocular surface and demand rating their functional actions beyond the gastrointestinal tract.

Prostanoids mediate the protective effect of intestinal trefoil factor in oxidant-induced intestinal epithelial cell injury: Role of cyclooxygenase-2

Prostanoids mediate the protective effect of intestinal trefoil factor in oxidant-induced intestinal epithelial cell injury: Role of cyclooxygenase-2