Therapeutic potential of Pien Tze Huang in colitis-associated colorectal cancer: mechanistic insights from a mouse model.

BACKGROUND: Pien Tze Huang (PZH), a traditional Chinese medicine formulation, is recognized for its therapeutic effect on colitis and colorectal cancer. However, its protective role and underlying mechanism in colitis-associated colorectal cancer (CAC) remain to be elucidated. METHODS: A CAC mouse model was established using AOM/DSS. Twenty mice were randomly divided into four groups (n = 5/group): Control, PZH, AOM/DSS, and AOM/DSS + PZH groups. Mice in the PZH and AOM/DSS + PZH group were orally administered PZH (250 mg/kg/d) from the first day of experiment, while the control and AOM/DSS group received an equivalent volume of distilled water. Parameters such as body weight, disease activity index (DAI), colon weight, colon length, colon histomorphology, intestinal tumor formation, serum concentrations of pro-inflammatory cytokines, proliferation and apoptosis in colon tissue were assessed. RNA sequencing was employed to identify the differentially expressed transcripts (DETs) in colonic tissues and related signaling pathways. Wnt/ß-Catenin Pathway-Related genes in colon tissue were detected by QPCR and immunohistochemistry (IHC). RESULTS: PZH significantly attenuated AOM/DSS-induced weight loss, DAI elevation, colonic weight gain, colon shortening, histological damage, and intestinal tumor formation in mice. PZH also notably decreased serum concentration of IL-6, IL-1ß, and TNF-α. Furthermore, PZH inhibited cell proliferation and promote apoptosis in tumor tissues. RNA-seq and KEGG analysis revealed key pathways influenced by PZH, including Wnt/ß-catenin signaling pathway. IHC staining confirmed that PZH suppressed the expression of ß-catenin, cyclin D1 and c-Myc in colonic tissues. CONCLUSIONS: PZH ameliorates AOM/DSS-induced CAC in mice by suppressing the activation of Wnt/ß-catenin signaling pathway.

Mitotic Spindle Positioning (MISP) Facilitates Colorectal Cancer Progression by Forming a Complex with Opa Interacting Protein 5 (OIP5) and Activating the JAK2-STAT3 Signaling Pathway.

Patients with inflammatory bowel disease (IBD) who experience long-term chronic inflammation of the colon are at an increased risk of developing colorectal cancer (CRC). Mitotic spindle positioning (MISP), an actin-binding protein, plays a role in mitosis and spindle positioning. MISP is found on the apical membrane of the intestinal mucosa and helps stabilize and elongate microvilli, offering protection against colitis. This study explored the role of MISP in colorectal tumorigenesis using a database, human CRC cells, and a mouse model for colitis-induced colorectal tumors triggered by azoxymethane (AOM)/dextran sodium sulfate (DSS) treatment. We found that MISP was highly expressed in colon cancer patient tissues and that reduced MISP expression inhibited cell proliferation. Notably, MISP-deficient mice showed reduced colon tumor formation in the AOM/DSS-induced colitis model. Furthermore, MISP was found to form a complex with Opa interacting protein 5 (OIP5) in the cytoplasm, influencing the expression of OIP5 in a unidirectional manner. We also observed that MISP increased the levels of phosphorylated STAT3 in the JAK2-STAT3 signaling pathway, which is linked to tumorigenesis. These findings indicate that MISP could be a risk factor for CRC, and targeting MISP might provide insights into the mechanisms of colitis-induced colorectal tumorigenesis.

Using aspirin to prevent and treat cancer.

This review will discuss evidence that aspirin possesses anticancer activity. Long-term observational retrospective studies on nurses and health professionals demonstrated that regular aspirin users had a significantly lower incidence of colorectal cancer (RCT). Prospective studies on patients with a high risk of developing colorectal polyps/cancer confirmed that aspirin use significantly lowered colorectal dysplasia. Numerous observational studies focused on the use of aspirin in a broad range of cancers demonstrating a consistent 20-30% preventive effect on cancer incidence and mortality. Random Controlled Trials provided conflicting results on the benefit of aspirin in preventing CRC. Based on the age, weight/body size of the subjects for reasons still being explored. Studies on rats/mice further demonstrated that treatment of animals with aspirin where colon cancer was induced chemically or genetically (APCMin mice) reduced colonic dysplasia and polyp formation. Aspirin treatment was also effective at reducing the growth of cancer cells transplanted into normal/immunocompromised mice, suggesting that aspirin may be effective in treating different cancers. This possibility is also supported in clinical studies that aspirin use pre- and postcancer diagnosis significantly reduced the metastatic spread of cancer and increased patient survival. Lastly, the importance of the antiplatelet actions of aspirin in the drug's anticancer activity and specifically cancer metastatic spread is discussed and the current controversy related to the conflicting recommendations of the USPSTF over the past five years on the use of aspirin to prevent CRC.

Bovine Milk Derived Exosomes Affect Gut Microbiota of DSS-Induced Colitis Mice.

The objective of this study was to investigate the effect of bovine milk derived exosomes (MDEs) on the gut microbiota of Dextran sodium sulfate (DSS)-induced colitis mice. Total of 42 specific pathogen free (SPF) male BALB/c mice (3 weeks old) were randomly assigned to three groups including control group, DSS group (DSS) and bovine milk derived exosome group (Exo), with 7 replicates/cages per treatment and two mice in one cage. 16S rRNA gene sequencing of cecal digesta samples was conducted. DSS significantly decreased the average daily feed intake of mice in DSS and Exo groups (P = 0.03). Shannon index of the DSS group was significantly lower than the control group (P < 0.05) whereas no difference between the control group and Exo group was observed. Administration of MDEs tended to increase the relative abundance of Campylobaterota. Compared to the control group, the relative abundance of Roseburia was significantly decreased in the DSS group (P < 0.05) whereas no difference between the Exo group and control group was observed. MDEs also tended to increase the relative abundance of Lachnospiraceae_UCG_006. In conclusion, oral administration of 10 µL MDEs (1 mg/mL) positively affected gut microbiota of DSS-induced colitis mice. The results of this study provided valuable reference for MDEs application in the prevention and treatment of colitis.

Infliximab Inhibits Colitis Associated Cancer in Model Mice by Downregulating Genes Associated with Mast Cells and Decreasing Their Accumulation.

Inflammatory bowel diseases (IBDs), such as Crohn's disease or ulcerative colitis, can be treated with anti TNF-alpha (TNF-α) antibodies (Abs), but they also put patients with IBDs at risk of cancer. We aimed to determine whether the anti TNF-α Ab induces colon cancer development in vitro and in vivo, and to identify the genes involved in colitis-associated cancer. We found that TNF-α (50 ng/mL) inhibited the proliferation, migration, and invasion of HCT8 and COLO205 colon cancer cell lines and that anti TNF-α Ab neutralized TNF-α inhibition in vitro. The effects of anti TNF-α Ab, infliximab (10 mg/kg) were investigated in mouse models of colitis-associated cancer induced by intraperitoneally injected azoxymethane (AOM: 10 mg/kg)/orally administered dextran sodium sulfate (DSS: 2.5%) (AOM/DSS) in vivo. Infliximab significantly attenuated the development of colon cancer in these mice. Microarray analyses and RT-qPCR revealed that mast cell protease 1, mast cell protease 2, and chymase 1 were up-regulated in cancer tissue of AOM/DSS mice; however, those mast cell related genes were downregulated in cancer tissue of AOM/DSS mice with infliximab. These results suggested that mast cells play a pivotal role in the development of cancer associated with colitis in AOM/DSS mice.

Methyl cinnamate protects against dextran sulfate sodium-induced colitis in mice by inhibiting the MAPK signaling pathway.

Effective and non-toxic therapeutic agents are lacking for the prevention and treatment of colitis. Previous studies found that methyl cinnamate (MC), extracted from galangal ( Alpinia officinarum Hance), has anti-inflammatory properties. However, whether MC is effective as anti-colitis therapy remains unknown. In this study, we investigate the therapeutic effects of MC on dextran sulfate sodium (DSS)-induced colitis in mice and further explore its potential mechanism of action. MC treatment relieves symptoms associated with DSS-induced colitis, including the recovery of DSS-induced weight loss, decreases the disease activity index score, and increases the colon length without toxic side effects. MC treatment protects the integrity of the intestinal barrier in mice with DSS-induced colitis and inhibits the overexpression of pro-inflammatory cytokines in vivo and in vitro. Moreover, the MAPK signaling pathway is found to be closely related to the treatment with MC of colitis. Western blot analysis show that phosphorylation of the p38 protein in colon tissues treated with MC is markedly reduced and phosphorylation levels of the p38, JNK and ERK proteins are significantly decreased in RAW 264.7 cells treated with MC, indicating that the mechanism of MC in treating DSS-induced colitis could be achieved by inhibiting the MAPK signaling pathway. Furthermore, 16S RNA sequencing analysis show that MC can improve intestinal microbial dysbiosis in mice with DSS-induced colitis. Altogether, these findings suggest that MC may be a novel therapeutic candidate with anti-colitis efficacy. Furthermore, MC treatment relieves the symptoms of colitis by inhibiting the MAPK signaling pathway and improving the intestinal microbiota.

Efficiency of Orexin-A for Inflammatory Flare and Mucosal Healing in Experimental Colitis: Comparison with the Anti-TNF Alpha Infliximab.

Inflammatory bowel diseases are chronic inflammation of the intestinal mucosa characterized by relapsing-remitting cycle periods of variable duration. Infliximab (IFX) was the first monoclonal antibody used for the treatment of Crohn's disease and ulcerative colitis (UC). High variability between treated patients and loss of IFX efficiency over time support the further development of drug therapy. An innovative approach has been suggested based on the presence of orexin receptor (OX1R) in the inflamed human epithelium of UC patients. In that context, the aim of this study was to compare, in a mouse model of chemically induced colitis, the efficacy of IFX compared to the hypothalamic peptide orexin-A (OxA). C57BL/6 mice received 3.5% dextran sodium sulfate (DSS) in drinking water for 5 days. Since the inflammatory flare was maximal at day 7, IFX or OxA was administered based on a curative perspective at that time for 4 days using intraperitoneal injection. Treatment with OxA promoted mucosal healing and decreased colonic myeloperoxidase activity, circulating concentrations of lipopolysaccharide-binding protein, IL-6 and tumor necrosis factor alpha (TNFα) and decreased expression of genes encoding cytokines in colonic tissues with better efficacy than IFX allowing for more rapid re-epithelization. This study demonstrates the comparable anti-inflammatory properties of OxA and IFX and shows that OxA is efficient in promoting mucosal healing, suggesting that OxA treatment is a promising new biotherapy.

Red Cabbage Juice-Mediated Gut Microbiota Modulation Improves Intestinal Epithelial Homeostasis and Ameliorates Colitis.

Gut microbiota plays a crucial role in inflammatory bowel diseases (IBD) and can potentially prevent IBD through microbial-derived metabolites, making it a promising therapeutic avenue. Recent evidence suggests that despite an unclear underlying mechanism, red cabbage juice (RCJ) alleviates Dextran Sodium Sulfate (DSS)-induced colitis in mice. Thus, the study aims to unravel the molecular mechanism by which RCJ modulates the gut microbiota to alleviate DSS-induced colitis in mice. Using C57BL/6J mice, we evaluated RCJ's protective role in DSS-induced colitis through two cycles of 3% DSS. Mice were daily gavaged with PBS or RCJ until the endpoint, and gut microbiota composition was analyzed via shotgun metagenomics. RCJ treatment significantly improved body weight (p ≤ 0.001), survival in mice (p < 0.001) and reduced disease activity index (DAI) scores. Further, RCJ improved colonic barrier integrity by enhancing the expression of protective colonic mucins (p < 0.001) and tight junction proteins (p ≤ 0.01) in RCJ + DSS-treated mice compared to the DSS group. Shotgun metagenomic analysis revealed an enrichment of short-chain fatty acids (SCFAs)-producing bacteria (p < 0.05), leading to increased Peroxisome Proliferator-Activated Receptor Gamma (PPAR-γ) activation (p ≤ 0.001). This, in turn, resulted in repression of the nuclear factor κB (NFκB) signaling pathway, causing decreased production of inflammatory cytokines and chemokines. Our study demonstrates colitis remission in a DSS-induced mouse model, showcasing RCJ as a potential modulator for gut microbiota and metabolites, with promising implications for IBD prevention and treatment.

Bamboo Shoot and Artemisia capillaris Extract Mixture Ameliorates Dextran Sodium Sulfate-Induced Colitis.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract and is characterized by recurrent chronic inflammation and mucosal damage of the gastrointestinal tract. Recent studies have demonstrated that bamboo shoot (BS) and Artemisia capillaris (AC) extracts enhance anti-inflammatory effects in various disease models. However, it is uncertain whether there is a synergistic protective effect of BS and AC in dextran sodium sulfate (DSS)-induced colitis. In the current study, we tested the combined effects of BS and AC extracts (BA) on colitis using in vivo and in vitro models. Compared with control mice, oral administration of DSS exacerbated colon length and increased the disease activity index (DAI) and histological damage. In DSS-induced colitis, treatment with BA significantly alleviated DSS-induced symptoms such as colon shortening, DAI, histological damage, and colonic pro-inflammatory marker expression compared to single extracts (BS or AC) treatment. Furthermore, we found BA treatment attenuated the ROS generation, F-actin formation, and RhoA activity compared with the single extract (BS or AC) treatment in DSS-treated cell lines. Collectively, these findings suggest that BA treatment has a positive synergistic protective effect on colonic inflammation compared with single extracts, it may be a highly effective complementary natural extract mixture for the prevention or treatment of IBD.

A High-Fat Western Diet Attenuates Intestinal Changes in Mice with DSS-Induced Low-Grade Inflammation.

BACKGROUND: A Western diet (WD) is associated with increased inflammation in the large intestine, which is often ascribed to the high dietary fat content. Intestinal inflammation in rodents can be induced by oral administration of dextran sodium sulfate (DSS). However, most studies investigating effects of WD and DSS have not used appropriate low-fat diets (LFDs) as control. OBJECTIVES: To compare the effects of a WD with those of an LFD on colon health in a DSS-induced low-grade colonic inflammation mouse model. METHODS: Six-week-old male C57BL/6JRj mice were fed an LFD (fat = 10.3% energy, n = 24) or a WD (fat = 41.2% energy, n = 24) for 15 wk [Experiment 1 (Exp.1)]. Half the mice on each diet (n = 12) then received 1% DSS in water for 6 d with the remainder (n = 12 in each diet) administered water. Disease activity, proinflammatory genes, inflammatory biomarkers, and fecal microbiota (16S rRNA) were assessed (Exp.1). Follow-up experiments (Exp.2 and Exp.3) were performed to investigate whether fat source (milk or lard; Exp.2) affected outcomes and whether a shift from LFD to WD 1 d prior to 1% DSS exposure caused an immediate effect on DSS-induced inflammation (Exp.3). RESULTS: In Exp.1, 1% DSS treatment significantly increased disease score in the LFD group compared with the WD group (2.7 compared with 0.8; P < 0.001). Higher concentrations of fecal lipocalin (11-fold; P < 0.001), proinflammatory gene expression (≤82-fold), and Proteobacteria were observed in LFD-fed mice compared with the WD group. The 2 fat sources in WDs (Exp.2) revealed the same low inflammation in WD+DSS mice compared with LFD+DSS mice. Finally, the switch from LFD to WD just before DSS exposure resulted in reduced colonic inflammation (Exp.3). CONCLUSIONS: Herein, WDs (with milk or lard) protected mice against DSS-induced colonic inflammation compared with LFD-fed mice. Whether fat intake induces protective mechanisms against DSS-mediated inflammation or inhibits establishment of the DSS-induced colitis model is unclear.

Camel milk modulates the gut microbiota and has anti-inflammatory effects in a mouse model of colitis.

Camel milk is a nutritionally rich food that shows anti-inflammatory, immune regulation, and gut microbiota maintenance properties. However, the relationship between camel milk and the intestinal microbiota during colitis is unclear. Herein, we evaluated the protective effect of camel milk in mice with colitis induced using dextran sodium sulfate. Our results showed that camel milk can prevent body weight loss and colon shortening, reduce the disease activity index, and attenuate colon tissue damage. Additionally, camel milk could reduce the overexpression of inflammatory factors, inhibit the apoptosis of intestinal epithelial cells, and promote the expression of claudin-1, occludin, and zonula occludens-1 proteins. Moreover, camel milk effectively regulated intestinal microbiota in mice with colitis by increasing the gut microbiota diversity, increasing the abundance of beneficial bacteria (such as g_norank_f_Muribaculaceae, and Lachnospiraceae_NK4A136_group), and reducing the number of harmful bacteria (Bacteroides, Escherichia-Shigella). In addition, camel milk increased the levels of intestinal short-chain fatty acids. The results of the present study demonstrated that via regulating the intestinal microbiota, maintaining intestinal barrier function, and inhibiting proinflammatory cytokines, camel milk can ameliorate dextran sodium sulfate-induced colitis.

Presume Why Probiotics May Not Provide Protection in Inflammatory Bowel Disease through an Azoxymethane and Dextran Sodium Sulfate Murine Model.

Recent studies have shown dysbiosis is associated with inflammatory bowel disease (IBD). However, trying to restore microbial diversity via fecal microbiota transplantation (FMT) or probiotic intervention fails to achieve clinical benefit in IBD patients. We performed a probiotic intervention on a simulated IBD murine model to clarify their relationship. IBD was simulated by the protocol of azoxymethane and dextran sodium sulfate (AOM/DSS) to set up a colitis and colitis-associated neoplasm model on BALB/c mice. A single probiotic intervention using Clostridium butyricum Miyairi (CBM) on AOM/DSS mice to clarify the role of probiotic in colitis, colitis-associated neoplasm, gut microbiota, and immune cytokines was performed. We found dysbiosis occurred in AOM/DSS mice. The CBM intervention on AOM/DSS mice failed to improve colitis and colitis-associated neoplasms but changed microbial composition and unexpectedly increased expression of proinflammatory IL-17A in rectal tissue. We hypothesized that the probiotic intervention caused dysbiosis. To clarify the result, we performed inverse FMT using feces from AOM/DSS mice to normal recipients to validate the pathogenic effect of dysbiosis from AOM/DSS mice and found mice on inverse FMT did develop colitis and colon neoplasms. We presumed the probiotic intervention to some extent caused dysbiosis as inverse FMT. The role of probiotics in IBD requires further elucidation.

Therapeutic effect of the sulforaphane derivative JY4 on ulcerative colitis through the NF-κB-p65 pathway.

The efficacy of the sulforaphane derivative JY4 was evaluated in acute and chronic mouse models of ulcerative colitis induced by dextran sodium sulfate. Oral administration of JY4 led to significant improvements in symptoms, with recovery of body weight and colorectal length, together with reduced diarrhoea, bloody stools, ulceration of colonic tissue and infiltration of inflammatory cells. The oral bioavailability of JY4, determined by comparing oral dosing with injection into the tail vein, was 5.67%, which was comply with the idea in the intestinal function. Using a dual-luciferase reporter assay, immunofluorescence studies, western blot analysis and immunohistochemical staining, JY4 was shown to significant interfere with the NF-κB-p65 signaling pathway. By preventing the activation of NF-κB-p65, JY4 inhibited the overexpression of downstream inflammatory factors, thereby exerting an anti-inflammatory effect on the intestinal tract. This study thus provides a promising candidate drug, and a new concept for the treatment of ulcerative colitis.

Targeted intestinal deletion of Rho guanine nucleotide exchange factor 7, ßPIX, impairs enterocyte proliferation, villus maturation, and mucosal defenses in mice.

Rho guanine nucleotide exchange factors (RhoGEFs) regulate Rho GTPase activity and cytoskeletal and cell adhesion dynamics. ßPix, a CDC42/RAC family RhoGEF encoded by ARHGEF7, is reported to modulate human colon cancer cell proliferation and postwounding restitution of rat intestinal epithelial monolayers. We hypothesized that ßPix plays a role in maintaining intestinal epithelial homeostasis. To test this hypothesis, we examined ßPix distribution in the human and murine intestine and created mice with intestinal epithelial-selective ßPix deletion [ßPixflox/flox/Tg(villin-Cre); Arhgef7 CKO mice]. Using Arhgef7 conditional knockout (CKO) and control mice, we investigated the consequences of ßPix deficiency in vivo on intestinal epithelial and enteroid development, dextran sodium sulfate-induced mucosal injury, and gut permeability. In normal human and murine intestines, we observed diffuse cytoplasmic and moderate nuclear ßPix immunostaining in enterocytes. Arhgef7 CKO mice were viable and fertile, with normal gross intestinal architecture but reduced small intestinal villus height, villus-to-crypt ratio, and goblet cells; small intestinal crypt cells had reduced Ki67 staining, compatible with impaired cell proliferation. Enteroids derived from control mouse small intestine were viable for more than 20 passages, but those from Arhgef7 CKO mice did not survive beyond 24 h despite addition of Wnt proteins or conditioned media from normal enteroids. Adding a Rho kinase (ROCK) inhibitor partially rescued CKO enteroid development. Compared with littermate control mice, dextran sodium sulfate-treated ßPix-deficient mice lost more weight and had greater impairment of intestinal barrier function, and more severe colonic mucosal injury. These findings reveal ßPix expression is important for enterocyte development, intestinal homeostasis, and resistance to toxic injury.NEW & NOTEWORTHY To explore the role of ßPix, a guanine nucleotide exchange factor encoded by ARHGEF7, in intestinal development and physiology, we created mice with intestinal epithelial cell Arhgef7/ßPix deficiency. We found ßPix essential for normal small intestinal epithelial cell proliferation, villus development, and mucosal resistance to injury. Moreover, Rho kinase signaling mediated developmental arrest observed in enteroids derived from ßPix-deficient small intestinal crypts. Our studies provide insights into the role Arhgef7/ßPix plays in intestinal epithelial homeostasis.

DSS-induced damage to basement membranes is repaired by matrix replacement and crosslinking.

Basement membranes are an ancient form of animal extracellular matrix. As important structural and functional components of tissues, basement membranes are subject to environmental damage and must be repaired while maintaining functions. Little is known about how basement membranes get repaired. This paucity stems from a lack of suitable in vivo models for analyzing such repair. Here, we show that dextran sodium sulfate (DSS) directly damages the gut basement membrane when fed to adult Drosophila DSS becomes incorporated into the basement membrane, promoting its expansion while decreasing its stiffness, which causes morphological changes to the underlying muscles. Remarkably, two days after withdrawal of DSS, the basement membrane is repaired by all measures of analysis. We used this new damage model to determine that repair requires collagen crosslinking and replacement of damaged components. Genetic and biochemical evidence indicates that crosslinking is required to stabilize the newly incorporated repaired Collagen IV rather than to stabilize the damaged Collagen IV. These results suggest that basement membranes are surprisingly dynamic.

Intestinal anastomotic healing models during experimental colitis.

BACKGROUND: Anastomotic leakage represents a major complication following resections in colorectal surgery. Among others, intestinal inflammation such as in inflammatory bowel disease is a significant risk factor for disturbed anastomotic healing. Despite technical advancements and several decades of focused research, the underlying mechanisms remain incompletely understood. Animal experiments will remain the backbone of this research in the near future. Here, instructions on a standardized and reproducible murine model of preoperative colitis and colorectal anastomosis formation are provided to amplify research on anastomotic healing during inflammatory disease. METHODS: We demonstrate the combination of experimental colitis and colorectal anastomosis formation in a mouse model. The model allows for monitoring of anastomotic healing during inflammatory disease through functional outcomes, clinical scores, and endoscopy and histopathological examination, as well as molecular analysis. DISCUSSION: Postoperative weight loss is used as a parameter to monitor general recovery. Functional stability can be measured by recording bursting pressure and location. Anastomotic healing can be evaluated macroscopically from the luminal side by endoscopic scoring and from the extraluminal side by assessing adhesion and abscess formation or presence of dehiscence. Histologic examination allows for detailed evaluation of the healing process. CONCLUSION: The murine model presented in this paper combines adjustable levels of experimental colitis with a standardized method for colorectal anastomosis formation. Extensive options for sample analysis and evaluation of clinical outcomes allow for detailed research of the mechanisms behind defective anastomotic healing.

Pharmacological inhibition of IRAK1 attenuates colitis-induced tumorigenesis in mice by inhibiting the inflammatory response and epithelial-mesenchymal transition.

Colorectal cancer (CRC) is the third most common type of cancer. Here, we studied the inhibitory effect of IRAK1 and IRAK4 as a preventive strategy using a colitis-induced tumorigenesis mouse model. CRC clinical data were obtained from the Gene Expression Omnibus (GEO). An experimental inflammation-dependent CRC model was induced by treatment with azoxymethane (AOM) and then dextran sodium sulfate (DSS) in C57BL/6 mice. Mice were administered an IRAK1/4 inhibitor by intraperitoneal injection at 3 mg/kg twice each week for 9 weeks. The IRAK1/4 inhibitor attenuated histological changes and prevented tumor growth. Tumor-associated proteins, including p65 and Ki-67, were downregulated by the IRAK1/4 inhibitor in AOM/DSS-treated mice. Additionally, IRAK1/4 inhibitor administration effectively decreased the expression of inflammatory cytokines. Furthermore, we observed that IRAK1/4 inhibitor treatment attenuated colitis-induced tumorigenesis by inhibiting epithelial-mesenchymal transition. These observations indicate that inhibition of IRAK1 and IRAK4 may suppress experimental colitis-induced tumorigenesis by inhibiting inflammatory responses and epithelial-mesenchymal transition.

The Impact of Dextran Sodium Sulfate-Induced Gastrointestinal Injury on the Pharmacokinetic Parameters of Donepezil and Its Active Metabolite 6-O-desmethyldonepezil, and Gastric Myoelectric Activity in Experimental Pigs.

Gastrointestinal side effects of donepezil, including dyspepsia, nausea, vomiting or diarrhea, occur in 20-30% of patients. The pathogenesis of these dysmotility associated disorders has not been fully clarified yet. Pharmacokinetic parameters of donepezil and its active metabolite 6-O-desmethyldonepezil were investigated in experimental pigs with and without small intestinal injury induced by dextran sodium sulfate (DSS). Morphological features of this injury were evaluated by a video capsule endoscopy. The effect of a single and repeated doses of donepezil on gastric myoelectric activity was assessed. Both DSS-induced small intestinal injury and prolonged small intestinal transit time caused higher plasma concentrations of donepezil in experimental pigs. This has an important implication for clinical practice in humans, with a need to reduce doses of the drug if an underlying gastrointestinal disease is present. Donepezil had an undesirable impact on porcine myoelectric activity. This effect was further aggravated by DSS-induced small intestinal injury. These findings can explain donepezil-associated dyspepsia in humans.

Loss of C/EBPδ enhances apoptosis of intestinal epithelial cells and exacerbates experimental colitis in mice.

Inflammatory bowel diseases (IBDs) are characterized by chronic inflammation involving intestinal tissue damage, which include ulcerative colitis and Crohn's disease as major entities. Accumulating evidence suggests that excessive apoptosis of intestinal epithelial cells (IECs) contributes to the development of IBD. It was recently reported that the transcription factor CCAAT/enhancer-binding protein delta (C/EBPδ) is involved in inflammation; however, its role in colitis remains unclear. Here, we found that C/EBPδ knockout mice showed enhanced susceptibility to dextran sodium sulfate (DSS)-induced colitis, a mouse model of IBD, which was associated with severe colonic inflammation and mucosal damage with increased IEC apoptosis. Additionally, DSS stimulation induced increased expression of pro-apoptotic BH3-only protein Bim in the colon of C/EBPδ knockout mice. Collectively, our findings demonstrate that C/EBPδ plays an essential role in suppressing DSS-induced colitis, likely by attenuating IEC apoptosis.

Elevated adenomatous polyposis coli in goblet cells is associated with inflammation in mouse and human colon.

NEW FINDINGS: What is the central question of this study? What is the localization and distribution pattern of adenomatous polyposis coli (APC) in intestinal epithelial cells? Does this distribution change in different regions of the colon or in the condition of inflammation? What is the main finding and its importance? Colonic epithelia from mice and humans contain a subset of goblet cells displaying high APC levels. The number of APChigh goblet cells increases in inflamed tissue, which also displays increased GRP78, indicating potential stress from mucin production. In cultured human colon cells, expression of interleukin 1 pathway components (inducers of MUC2 expression) is reduced upon APC depletion raising the potential for APC participation in an inflammatory response. ABSTRACT: Adenomatous polyposis coli (APC) serves as a gatekeeper of intestinal homeostasis by promoting cellular differentiation and maintaining crypt architecture. Although appreciated as a critical colon tumour suppressor, roles for APC in disease states such as inflammation have yet to be fully delineated. This study aimed to characterize the localization of APC protein in gastrointestinal tissues from human patients with active inflammatory bowel disease and mice with dextran sodium sulfate (DSS)-induced colitis. Fluorescence immunohistochemistry revealed a subset of goblet cells with elevated Apc staining intensity in the small intestines and proximal/medial colons of mice. Upon induction of colitis with DSS, these 'APChigh ' goblet cells remained in the proximal and medial colon, but now were also observed in the distal colon. This phenotype was recapitulated in humans, with APChigh goblet cells observed only in the descending colons of patients with active ulcerative colitis. In cultured human colon cells derived from normal tissue, APC depletion reduced expression of mRNAs encoding the interleukin 1 (IL1) signalling pathway components IL1ß and interleukin-1 receptor (IL1R), known regulators of Muc2 expression. Treating cancer cells lacking wild-type APC with IL1ß, or induction of full-length APC in these cells led to increases in IL1R and MUC2 expression. Combining IL1ß treatment with APC induction led to an increase of MUC2 expression greater than expected for additive affects, suggesting that APC sensitizes cells to IL1 signalling. These findings suggest that APC has novel roles in maintaining proper goblet cell function, thus providing further evidence for APC as an important factor in intestinal tissue homeostasis and disease.