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Inflammatory bowel disease (IBD) is a complex disease with an incompletely understood multifactorial etiopathogenesis. The importance of intestinal microbiota in IBD and the role of probiotics in the treatment are being extensively investigated. This study evaluated the therapeutic effects of Bifidobacterium animalis subsp. lactis BB-12, Lactobacillus reuteri, Saccharomyces boulardii and Bacillus clausii in trinitrobenzene sulfonic acid (TNBS)-induced colitis animal model. Rats were randomly grouped into 7: control, colitis, colitis+BB-12, colitis+L. reuteri, colitis+S. boulardii, colitis+B. clausii and colitis+methylprednisolone (positive control) treatment groups. Colitis was induced by the administration of intracolonically 80 mg/kg TNBS. Treatments continued for 7 days. Body weight, stool consistency, rectal bleeding, and disease activity index (DAI) scores were evaluated and recorded daily. Macroscopic and microscopic colonic damage were evaluated and scored in the last day of experiment. Levels of malondialdehyde (MDA) and (GSH) and activity of myeloperoxidase (MPO) in the colonic tissues were detected by ELISA. Our results showed that treatments with BB-12, L. reuteri, S. boulardii and B. clausii significantly improved on clinical symptoms and decreased macroscopic and microscopic colonic damage on experimental colitis in rats. In addition, L. reuteri and S. boulardii significantly increased GSH levels and decreased MDA levels and MPO activity. When we evaluate our findings, we think that supplements of these specific probiotics may have beneficial effects in the treatment of IBD. [ABSTRACT FROM AUTHOR]

Background: Previous studies implicated matrix metalloproteinases (MMPs), such as MMP-7, in inflammatory bowel diseases (IBD) by showing increased activity during inflammation of the gut. However, the pathophysiological roles of MMP-7 have not been clearly elucidated. Methods: The expression of MMP-7 was assessed in colonic biopsies of patients with ulcerative colitis (UC), in rodents with experimental colitis, and in cell-based assays with cytokines. Wild-type and MMP-7-null mice treated with dextran sulfate sodium (DSS) or trinitrobenzene sulfonic acid were used for determining the pro-inflammatory function(s) of MMP-7 in vivo. Results: MMP-7 was highly expressed in patients with UC and in rodents with experimental colitis. IL-1β, IL-4, IL-13, TNFα, or lipopolysaccharide enhanced MMP-7 expression in human colonic epithelial cells, rat colonic smooth muscle cells, and THP-1-derived macrophages. Active MMP-7 degraded tight junction protein Claudin-7 in epithelial cells, cleaved recombinant Claudin-7 in cell-free system, and increased Caco-2 monolayer permeability. Immunostaining of colon biopsies revealed up-regulation of MMP-7 and reduction of Claudin-7 in UC patients. Compared to wild-type mice, Mmp7-/- mice had significantly less inflammation in the colon upon DSS insult. DSS-induced alterations in junction proteins were mitigated in Mmp7-/- mice, suggesting that MMP-7 disrupts the intestinal barrier. MMP-7 antibody significantly ameliorated colonic inflammation and Claudin-7 reduction in 2 different rodent models of colitis. Summary: MMP-7 impairs intestinal epithelial barrier by cleavage of Claudin-7, and thus aggravating inflammation. These studies uncovered Claudin-7 as a novel substrate of MMP-7 in the intestinal epithelium and reinforced MMP-7 as a potential therapeutic target for IBD. [ABSTRACT FROM AUTHOR]

Crohn's disease (CD) and ulcerative colitis (UC) are both highly inflammatory diseases of the gastrointestinal tract, collectively known as inflammatory bowel disease (IBD). Although the cause of IBD is still unclear, several experimental IBD murine models have enabled researchers to make great inroads into understanding human IBD pathology. Here, we discuss the current pre-clinical experimental murine models for human IBD, including the chemical-induced trinitrobenzene sulfonic acid (TNBS) model, oxazolone and dextran sulphate sodium (DSS) models, the gene-deficient I-kappa-B kinase gamma (Iκκ-γ) and interleukin(IL)-10 models, and the CD4+ T-cell transfer model. We offer a comprehensive review of how these models have been used to dissect the etiopathogenesis of disease, alongside their limitations. Furthermore, the way in which this knowledge has led to the translation of experimental findings into novel clinical therapeutics is also discussed. [ABSTRACT FROM AUTHOR]

Background: Inflammatory bowel disease (IBD) is a world healthcare problem. In order to evaluate the effect of new pharmacological approaches for IBD, we aim to develop and validate chronic trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Methods: Experimental colitis was induced by the rectal administration of multiple doses of TNBS in female CD-1 mice. The protocol was performed with six experimental groups, depending on the TNBS administration frequency, and two control groups (sham and ethanol groups). Results: The survival rate was 73.3% in the first three weeks and, from week 4 until the end of the experimental protocol, the mice's survival remained unaltered at 70.9%. Fecal hemoglobin presented a progressive increase until week 4 (5.8 ± 0.3 µmol Hg/g feces, p < 0.0001) compared with the ethanol group, with no statistical differences to week 6. The highest level of tumor necrosis factor-α was observed on week 3; however, after week 4, a slight decrease in tumor necrosis factor-α concentration was verified, and the level was maintained until week 6 (71.3 ± 3.3 pg/mL and 72.7 ± 3.6 pg/mL, respectively). Conclusions: These findings allowed the verification of a stable pattern of clinical and inflammation signs after week 4, suggesting that the chronic model of TNBS-induced colitis develops in 4 weeks. [ABSTRACT FROM AUTHOR]

Purpose: Evaluate the efficacy of hydroxytyrosol in the local treatment of inflammatory colitis. Currently, the existing treatments for inflammatory bowel diseases does not cure the disease and it is associated with high rates of side effects and complications. Hydroxytyrosol is a phenyl-ethyl-alcohol derived from the hydrolysis of oleuropein and present in olive oil, previous studies have demonstrated the anti-inflammatory effect of dietary hydroxytyrosol supplement, with no toxicity. Materials & Methods: Colitis has been induced by using Trinitrobenzene Sulfonic Acid at 40 rats. They were divided into four groups randomly: 10 rats without treatment; 10 rats with pectin/alginate mixture; 10 rats treated with pectin/alginate + olive oil; 10 rats treated with pectin/alginate + olive oil + hydroxytyrosol. Animals were sacrificed 10 days after induction of trinitrobenzene sulfonic acid, receiving 5 days of continuous treatment. Samples of the rectal area were studied and observed under a microscope to determine the damage by Hunter scoring modified, assessing inflammatory infiltration, number of intestinal walls involved, damage to the mucosal architecture, and edema. Results: When the rectum was analyzed in a global way, nonsignificant differences were observed; however, when performing an individualized analysis, statistically significant differences in the inflammatory infiltrate are present in the samples, which were evaluated using the ANOVA and Student-T statistics. Conclusions: Local treatment with the natural antioxidant hydroxytyrosol combined with pectin/alginate and olive oil of inflammatory bowel disease has been shown to be effective against inflammatory infiltration of TNBS-induced colitis. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effect of cell division cycle protein 42 (CDC42) on inflammatory response and immune response in mice bearing inflammatory bowel disease (IBD). Trinitrobenzene sulfonic acid was injected into the colon of mice to establish IBD model. The mice were divided into four groups (n = 4): control, model, Ad5, and Ad5-CDC42. After establishing IBD model, mice which were treated with AD5 empty vector and AD5-CDC42 expression vector served as the Ad5 group and Ad5-CDC42 group, respectively. The mRNA and protein levels of interleukin 10 (IL-10), interferon-γ (IFN-γ), IL-4, and tumor necrosis factor-α (TNF-α) in the colon tissues were evaluated by RT-PCR and western blot, respectively. Their levels in the serum and colon tissues were examined by ELISA assay and immunohistochemical analysis, respectively. Their changes in the mRNA and protein levels were consistent and similar changes in the colon tissues and the serum were found among various groups. The levels of IL-10, IFN-γ, IL-4, and TNF-α were lowest in the control group. Their levels in the model group and the Ad5 group were similar (p >.05) and significantly higher than those in the control group (p <.05). In comparison with the model group and the Ad5 group, their levels were significantly reduced in the Ad5-CDC42 group (p <.05). In conclusion, the levels of inflammatory cytokines were elevated in the colon tissues and serum of IBD mice, which could be reduced by the CDC42 treatment. CDC42 regulated the inflammatory response and the innate immune response in IBD mice. [ABSTRACT FROM AUTHOR]

Abstract Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease (CD), are chronic autoimmune diseases with a high recurrence rate. Epidemiological data have shown that the incidence of IBD increases annually because of improved sanitary conditions and reduced parasitic infection rates. In this experiment, experimental colitis was induced in mice by administering 2,4,6-trinitrobenzene sulfonic acid (TNBS) 28 days after they were infected with Trichinella spiralis to confirm that T. spiralis infection could alleviate the severity of TNBS-induced colitis. Thirty-six male BALB/c mice aged 6–8 weeks were randomly divided into four groups: control group (with 50% ethanol, Control), T. spiralis -infected group (TS-Control), TNBS-induced colitis model group (Colitis), and T. spiralis -pre-infected and TNBS-induced colitis group (TS-Colitis). The mice were sacrificed 3, 7, and 14 days after the model was established. Changes in various colitis indicators to investigate the effect of T. spiralis infection on TNBS-induced murine CD model. Results showed that the weight, DAI score, and macroscopic and microscopic colon damage in the TS-Colitis significantly decreased compared with those in the Colitis. ELISA revealed that the IFN-γ expression decreased and the IL-4 expression increased in the TS-Colitis compared with those in the Colitis. Western Blotting results revealed that the NF-κB expression increased in the Colitis and higher than those in the TS-Colitis. And Flow cytometry results revealed that the percentage of CD4+CD25+Foxp3+ Treg cells significantly increased in the TS-Colitis. T. spiralis -infected mice induced Th2 immune responses and balanced Th1 immune responses stimulated by TNBS to ameliorate intestinal inflammation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Chemically-induced colitis causes colonic damage, increasing oxidative stress in the blood. • A single oral dose of Trichilia catigua extract reduces oxidative stress markers. • Trichilia catigua extract improves wound healing, reducing colonic damage. • Oral administration of the extract is more efficacious than an enema. Abstract Beverages containing Trichilia catigua are commonly employed in folk medicine. T. catigua bark extracts possess antioxidant, anti-inflammatory, and bactericidal properties. These properties suggest T. catigua bark extracts as a potential treatment for inflammatory bowel diseases (IBD). Using the 2,4,6-trinitrobenzenesulphonic acid (TNBS)-induced model of colitis in rats we evaluated the effect of an ethyl-acetate fraction (EAF) of T. catigua (200 mg/kg) administered by daily oral gavage or intrarectally at different time points after TNBS challenge. TNBS treatment evoked severe colonic inflammation after 24 h that persisted for 7 days, characterized by weight loss, high levels of myeloperoxidase activity, histological and macroscopic damage, and elevated index of oxidative stress in the blood. T. catigua EAF treatment prevented the oxidative stress within 24 h and enhanced tissue recovery observed at day 7, returning histological and macroscopic damage levels to that of the control group. TNBS treatment led to loss of myenteric neurons after 28 days. T. catigua EAF was unable to prevent the neuronal loss. Oral delivery of T. catigua EAF was more effective than intrarectal administration of the extract. In conclusion, T. catigua EAF treatment normalized oxidative stress parameters in blood and reduced the degree of acute inflammation in TNBS colitis. [ABSTRACT FROM AUTHOR]

Background Regulatory T (Treg) cells and T helper 17 (Th17) cells play crucial roles in ulcerative colitis (UC). Kuijieling (KJL) is an effective Chinese medicine formula for treating UC in clinic. Kuijieling has shown remedy effect on the imbalance between Treg and Th17 cells. This study aimed to further reveal the exact underlying mechanism of how Kuijieling regulates the differentiation of Treg and Th17 cells in the treatment of UC. Methods Colitis was induced by trinitrobenzene sulfonic acid in rats and treated by KJL. Pathological injury was evaluated by HE staining and pathological score. Transforming growth factor-β1 (TGF-β1), interleukin(IL)-2, IL-6, IL-10, IL-17, IL-23 and IL-21 in plasma were assayed by ELISA. Forkhead box P3 (Foxp3), signal transducer and activator of transcription (STAT) 5 expressed in colon mucosa were measured by western blot. Immunohistochemistry was employed for quantifying retinoic acid-related orphan receptor γt (RORγt) and STAT3 in colon. RT-PCR was used to analyze the expression of IL-2, IL-17, IL-23, IL-21 mRNA in colon. Results After the administration of KJL, pathological injury in colon mucosa was reduced and histological score was decreased, transforming growth factor-β1 (TGF-β1), interleukin(IL)-2, IL-10 in blood and Foxp3, STAT5, IL-2 in colon increased significantly, IL-6, IL-23, IL-17, IL-21 in blood and RORγt, STAT3, IL-23, IL-17, IL-21 in colon decreased. Our result showed that KJL regulates the related cytokines and transcription factors to promote Treg cells and suppress Th17 cells. Conclusion KJL restores the balance between Treg and Th17 cells through regulating the differentiation of them, therefore contributes to the treatment of UC. [ABSTRACT FROM AUTHOR]

Introduction:Amomum villosum Lour., a herbaceous plant in the ginger family, has been proven to be effective in treating gastrointestinal diseases. It has been listed in the Chinese Pharmacopeia as a legal source of Amomi Fructus. In our previous study, we demonstrated that treatment with extracts of A. villosum prevented the development and progression of intestinal mucositis. In the current study, we aimed to verify and explain the potential beneficial effects of A. villosum on inflammatory bowel disease (IBD). Methods: The effect of water extracts (WEAV) and volatile oil of A. villosum (VOAV) were evaluated on the immunological role of T lymphocytes and intestinal microecology in IBD rats induced with 2,4,6-trinitrobenzenesulfonic acid (TNBS). Body weight, food intake, colon length/weight, and disease activity index (DAI) as well as tissue damage scores were evaluated. The inflammatory response to IBD was assessed by measuring the expression of myeloperoxidase, interleukin (IL)-17 (IL-17), interferon-γ (IFN-γ), IL-10, tumor necrosis factor-α (TNF-α), and transforming growth factor-β (TGF-β). The percentage of regulatory CD4+ T cells in rat spleen was measured by flow cytometry and effects on the microbial community were evaluated by 16S rDNA gene sequencing. Results: All TNBS-induced rats showed typical clinical manifestations of IBD. IBD rats in the WEAV and VOAV treatment groups were effective in relieving body weight and appetite loss. Middle and high dosage of VOAV and WEAV significantly reduced the DAI, and tissue damage scores, whereas colon weight/length ratio was increase. All rats in the WEAV and VOAV groups showed significantly decreased IFN-γ levels and increased levels of IL-10 and TGF-β. Moreover, we observed that the percentage of regulatory CD4+ T cells was significantly enhanced during treatment with WEAV. In addition, administration of WEAV and VOAV effectively inhibited the release of enterogenic endotoxin, increased short-chain fatty acid-producing bacteria belonging to Firmicutes and Bacteroidetes, and decreased the abundance of Proteobacteria. Conclusion: Treatment with WEAV and VOAV significantly attenuated intestinal inflammation in IBD rats, which was possibly associated with its regulation on inflammatory cytokine and CD4+CD25+FOXP3+ T cells. Moreover, WEAV and VOAV may help maintaining the balance of intestinal microecology. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the protective effects of magnolol on acute 2,4,6‑trinitrobenzene sulfonic acid (TNBS)‑induced colitis, and its underlying mechanisms. Experimental colitis was induced by intracolonic administration of TNBS/ethanol into rats. The model rats were randomly assigned into groups: TNBS, magnolol (high, medium and low doses), and salazosulfapyridine (positive control). All intervention regimens were administered by oral gavage, once a day for 7 consecutive days, 24 h after colitis induction. Histological and biochemical changes in colonic inflammation were evaluated by hematoxylin and eosin and immunohistochemistry, respectively. Rats treated with all doses of magnolol exhibited decreased colonic myeloperoxidase activity (P<0.05 vs. TNBS), reduced serum levels of proinflammatory cytokines [including interleukin (IL)‑6 and IL‑17], and downregulated Toll‑like receptor-4 (TLR‑4) mRNA expression. Histological analysis revealed that medium and high doses of magnolol conferred an anti‑inflammatory effect, which was indicated by a decrease in disease activity index, an increase in thymus index, and downregulation of nuclear factor (NF)‑κB p65 mRNA and TLR‑4 protein expression. However, only high‑dose magnolol significantly ameliorated the elevated colon weight/length ratio. The results of the present study indicate that magnolol exerts protective effects against acute TNBS‑induced colitis in rats, and the TLR‑4/NF‑κB signaling pathway‑mediated inhibitory effect on inflammatory cascades may contribute to the protective activity of magnolol. [ABSTRACT FROM AUTHOR]

Thiadiazolidinone-8 (TDZD-8) is an effective thiadiazolidinone derivate that is able to suppress the expression of inflammatory cytokines; it also presents tissue protective actions by glycogen synthase kinase (GSK)-3β inhibition, promoting thus an anti-inflammatory effect. Since inflammatory bowel disease is a chronic disease with reduced quality of life, where currently available therapies are only able to induce or maintain the patient in remission, it is crucial to investigate new pharmacological approaches. The main objective of this study was to evaluate the effect of TDZD-8 in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Male CD-1 mice with TNBS-induced colitis were treated with a daily dose of TDZD-8 5 mg/kg/day IP during 4 days. The anti-inflammatory properties of TDZD-8 in the TNBS-induced colitis were confirmed by suppression of pro-inflammatory mediators, such as tumor necrosis factor (TNF)-α, in-terleukin (IL)-1β and myeloperoxidase, as well as by the significant increase of the anti-inflammatory cytokine, IL-10. These treated mice also presented a reduction in fecal hemoglobin and alkaline phosphatase, suggesting a beneficial effect of TDZD-8. Furthermore, renal and hepatic biomarkers remained stabilized after treatment. In conclusion, TDZD-8 reduces the inflammatory response associated with TNBSinduced colitis in mice, and modulation of GSK-3β seems to be an interesting pharmacological target in colitis. [ABSTRACT FROM AUTHOR]

Background: The incidence of inflammatory bowel diseases (IBD) is increasing worldwide with patients experiencing severe impacts on their quality of life. It is well accepted that intestinal inflammation associates with extensive damage to the enteric nervous system (ENS), which intrinsically innervates the gastrointestinal tract and regulates all gut functions. Hence, treatments targeting the enteric neurons are plausible for alleviating IBD and associated complications. Mesenchymal stem cells (MSCs) are gaining wide recognition as a potential therapy for many diseases due to their immunomodulatory and neuroprotective qualities. However, there is a large discrepancy regarding appropriate cell doses used in both clinical trials and experimental models of disease. We have previously demonstrated that human bone marrow MSCs exhibit neuroprotective and anti-inflammatory effects in a guinea-pig model of 2,4,6-trinitrobenzene-sulfonate (TNBS)-induced colitis; but an investigation into whether this response is dose-dependent has not been conducted. Methods: Hartley guinea-pigs were administered TNBS or sham treatment intra-rectally. Animals in the MSC treatment groups received either 1 × 105, 1×106 or 3 × 106 MSCs by enema 3 hours after induction of colitis. Colon tissues were collected 72 hours after TNBS administration to assess the effects of MSC treatments on the level of inflammation and damage to the ENS by immunohistochemical and histological analyses. Results: MSCs administered at a low dose, 1 × 105 cells, had little or no effect on the level of immune cell infiltrate and damage to the colonic innervation was similar to the TNBS group. Treatment with 1 × 106 MSCs decreased the quantity of immune infiltrate and damage to nerve processes in the colonic wall, prevented myenteric neuronal loss and changes in neuronal subpopulations. Treatment with 3 × 106 MSCs had similar effects to 1 × 106 MSC treatments. Conclusions: The neuroprotective effect of MSCs in TNBS colitis is dose-dependent. Increasing doses higher than 1 × 106 MSCs demonstrates no further therapeutic benefit than 1 × 106 MSCs in preventing enteric neuropathy associated with intestinal inflammation. Furthermore, we have established an optimal dose of MSCs for future studies investigating intestinal inflammation, the enteric neurons and stem cell therapy in this model. [ABSTRACT FROM AUTHOR]

Excess proinflammatory cytokines owing to the activation of NF-κB and NLRP3 inflammasome play the key role in inflammatory bowel disease (IBD). Previously, we reported the anti-inflammatory activity of carboxyamidotriazole (CAI) resulting from decreasing cytokines. Therefore, we investigated the therapeutic effects of CAI in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rat colitis and the involvement of CAI action with NLRP3 inflammasome and NF-κB pathway. CAI was orally administered to TNBS-induced colitis rat. The severity of colitis was assessed, and NLRP3 inflammasome, NF-κB pathway and cytokines were determined. Our results showed that CAI significantly reduced weight loss and disease activity index (DAI) scores in colitis rats and alleviated the colonic macroscopic signs and pathological damage. In addition, the intestinal inflammatory markers and permeability index were markedly ameliorated by CAI treatment. The decreased levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, IL-18 were also detected in the colon tissues of CAI-treated colitis rats. Moreover, the activation of NLRP3 inflammasome in inflamed colon was significantly suppressed by showing an obvious reduction in the NLRP3 and activated caspase-1 levels. Furthermore, CAI reduced NF-κB p65 expression and IκBα phosphorylation and degradation in colitis rats. Therefore, CAI attenuates TNBS-induced colitis, which may be attributed to its inhibition of NLRP3 inflammasome and NF-κB activation, and down-regulation of proinflammatory cytokines. These results provide further understanding of the intestinal anti-inflammatory effect of CAI and highlight it as a potential drug for the treatment of IBD. [ABSTRACT FROM AUTHOR]

Purpose: The CD8+CD28+/CD8+CD28- T lymphocyte balance is vital for human ulcerative colitis (UC) but has not been defined in experimental colitis. This investigation will try to identify the changes that occur in the CD8+CD28+/CD8+CD28- T lymphocyte balance during the progression of trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats.Methods: The frequencies of blood CD8+CD28+ and CD8+CD28- T lymphocytes were detected in the rats belonging to the normal, model, and treated groups on five days using flow cytometry. The treated rats were administered with mesalazine and were euthanized after a 14-day treatment, as were the normal and model rats. The sensitivity and specificity of the CD8+CD28+/CD8+CD28- T lymphocyte balance in diagnosing early colitis were analyzed by receiver operating characteristics (ROC) curves. The frequencies of CD8+CD28+ and CD8+CD28- T lymphocytes in the colon tissue were tested via immunofluorescence. ELISA was used to measure the levels of the cytokines. Immunohistochemistry and Western blotting were used to detect the colonic expression of JAK3, STAT6, NFATc2, and GATA3.Results: We found that the ratio of CD8+CD28+/CD8+CD28- T lymphocytes decreased, as did the level of interleukin-7, but not IL-12p40, IL-13, or IL-15, in the blood; however, the ratio increased along with JAK3, STAT6, NFATc2, and GATA3 in the colon of the rats with colitis. The changes were effectively reversed through the administration of mesalazine for 13 days. Surprisingly, the balance in the blood could sensitively distinguish rats with early colitis from normal rats.Conclusion: These data show that increase in CD8+CD28+ T cells in blood and decrease in CD8+CD28- T cells in colon are associated with experimental colitis. [ABSTRACT FROM AUTHOR]

By performing two high-content small molecule screens on dextran sodium sulfate- and trinitrobenzene sulfonic acid-induced zebrafish enterocolitis models of inflammatory bowel disease, we have identified novel anti-inflammatory drugs from the John Hopkins Clinical Compound Library that suppress neutrophilic inflammation. Live imaging of neutrophil distribution was used to assess the level of acute inflammation and concurrently screen for off-target drug effects. Supporting the validity of our screening strategy, most of the anti-inflammatory drug hits were known antibiotics or anti-inflammatory agents. Novel hits included cholecystokinin ( CCK) and dopamine receptor agonists. Using a pharmacological approach, we show that while CCK and dopamine receptor agonists alleviate enterocolitis-associated inflammation, receptor antagonists exacerbate inflammation in zebrafish. This work highlights the utility of small molecule screening in zebrafish enterocolitis models as a tool to identify novel bioactive molecules capable of modulating acute inflammation. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the expression of decorin (DCN) in the intestinal tissues of mice with inflammatory bowel disease (IBD) and its correlation with autophagy. The IBD mouse model was created by intrarectal injection of trinitrobenzene sulfonic acid. The pathology of colon tissues of the mice was examined using hematoxylin and eosin staining. Expression of DCN and the proteins associated with autophagy was detected using immunohistochemistry. Normal human colon mucosal epithelial cells (NCM460 cells) were transfected with DCN expression plasmid and the expression of DCN and autophagy-associated proteins was detected by western blot analysis. Cell apoptosis was studied using an Annexin V apoptosis detection assay and intracellular autophagosomes were observed using electron microscopy. The IBD mouse model was successfully established. Thickening, edema and inflammatory cell infiltration of the intestinal wall were observed in the IBD mice. The expression of DCN as well as the autophagy-associated proteins beclin 1 and LC3B, was increased in the intestinal tissues of the IBD mice. Furthermore, in the NCM460 cells transfected with DCN, the expression of beclin 1 and LC3B was upregulated, while p62 expression was downregulated. Intracellular autophagosomes were increased and apoptosis was decreased in the cells with DCN overexpression. Inhibition of autophagy reversed the effects of DCN on apoptosis. Therefore, DCN is able to induce autophagy and protect intestinal cells during the occurrence and development of IBD. [ABSTRACT FROM AUTHOR]

Interleukin-10 (IL-10)-deficient mice spontaneously develop T cell-mediated colitis. Previous reports have shown that Matrine may reduce the symptoms of acute colitis induced by trinitrobenzene sulfonic acid (TNBS). However, whether Matrine impacts chronic colitis remains unknown. In this study, we investigated whether Matrine could limit the symptoms of spontaneously developed colitis and its potential molecular mechanisms. IL-10 deficient mice were given Matrine or a PBS control by oral gavage daily for 4 weeks and were euthanized at week 2 or week 4. We measured body weight, colon length and weight, and histological scores. We also evaluated the spontaneous secretion of IL-12/23p40, IFN-γ and IL-17 in colon explant cultures as well as IFN-γ and IL-17 secretion in unseparated mesenteric lymph node (MLN) cells, and assessed IFN-γ, IL-17, IL-1β and IL-6 mRNA expression in colon tissue. In addition, we analyzed the proportions of CD4-positive and CD8-positive cells in unseparated MLN cells. Our results show that Matrine-treated mice exhibited better body weight recovery than controls and that histological scores and spontaneously secreted IL-12/23p40, IFN-γ and IL-17 in colon tissue were significantly decreased in treated mice compared with controls. The proportion of CD4-positive cells of MLNs in treated mice was significantly smaller than that in controls at week 4. Both cytokine production and mRNA expression of IFN-γ and IL-17 were significantly reduced in treated mice compared with controls. Taken together, our results indicate that Matrine may ameliorate spontaneously developed chronic colitis and could be considered as a therapeutic alternative for chronic colitis. [ABSTRACT FROM AUTHOR]

Periostin is a matricellular protein that interacts with various integrin molecules on the cell surface. Although periostin is expressed in inflamed colonic mucosa, its role in the regulation of intestinal inflammation remains unclear. We investigated the role of periostin in intestinal inflammation using Postn-deficient (Postn-/-) mice. Intestinal epithelial cells (IECs) were transfected by Postn small interfering RNAs. Periostin expression was determined in colon tissue samples from ulcerative colitis (UC) patients. Oral administration of dextran sulfate sodium (DSS) or rectal administration of trinitrobenzene sulfonic acid, induced severe colitis in wild-type mice, but not in Postn-/- mice. Administration of recombinant periostin induced colitis in Postn-/- mice. The periostin neutralizing-antibody ameliorated the severity of colitis in DSS-treated wild-type mice. Silencing of Postn inhibited inteleukin (IL)-8 mRNA expression and NF-κB DNA-binding activity in IECs. Tumor necrosis factor (TNF)-α upregulated mRNA expression of Postn in IECs, and recombinant periostin strongly enhanced IL-8 expression in combination with TNF-α, which was suppressed by an antibody against integrin αv (CD51). Periostin and CD51 were expressed at significantly higher levels in UC patients than in controls. Periostin mediates intestinal inflammation through the activation of NF-κB signaling, which suggests that periostin is a potential therapeutic target for inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Ethyl pyruvate (EP), a simple lipophilic pyruvate ester, has demonstrated protective effects against murine colitis through inhibition the release of inflammatory factor high-mobility group protein box 1 (HMGB1). HMGB1 has been implicated in several autoimmune diseases by inducing Thl and Thl7 cells activation. This study was designed to investigate whether EP amelioration of murine colitis is related to the blocking of the HMGB1-Th17/Thl pathway. We induced murine colitis by intrarectal administration of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS). Ethyl pyruvate was injected intraperitoneally once a day for 7 days. One week after intrarectal challenge with TNBS, HMGB1, IL-17 and IFN-γ protein levels were remarkably increased following severe colon inflammation. Meanwhile, excessive infiltration of Th17 cells in colonic tissues, and an upregulated proportion of Th17 and Th1/Tc1 cells in the spleen and mesenteric lymph nodes (MLN) were found in the TNBS-treated group compared to the control group. Treatment with the HMGB1 inhibitor EP not only remarkably improved colon pathological damage, but also significantly reduced the number of Th17 cells in the local tissues of the colitis-induced mice. Furthermore, the percentage of Th1/Tc1 and Th17 cells in the spleen and MLN, as well as levels of serum IFN-γ and IL-17A, were all markedly decreased in the EP-treated group. Moreover, in vitro, our results showed that EP in a dose dependent manner inhibited HMGB1 release induced by LPS from CT26 cells (murine colon adenocarcinoma cell line). These results suggest that HMGB1 contributes to the development of murine colitis by promoting the Th17 and Th1/Tc1 responses, and that EP can significantly inhibit HMGB1-Th17 and Thl/Tc1 pathway activation, which may provide better protection to mice with TNBS-induced colitis. [ABSTRACT FROM AUTHOR]

Triptolide is known to exert anti-inflammatory and immunomodulatory activities; however, its impact on intestinal fibrosis has not been previously examined. Based on our previous studies of the suppressive activity of triptolide on human colonic subepithelial myofibroblasts and the therapeutic efficacy of triptolide in Crohn's disease, it was hypothesized that triptolide may have beneficial effects on intestinal fibrosis. In the present study, colonic fibrosis was induced in rats by 6 weekly repeated administration with a low-dose of 2,4,6-trinitrobenzene sulfonic acid (TNBS) and was then treated with triptolide or PBS daily (control) simultaneously. Extracellular matrix (ECM) deposition in the colon was examined with image analysis of Masson Trichrome staining. Total collagen levels in colonic homogenates were measured by a Sircol assay. Collagen Iα1 transcripts and collagen I protein were measured ex vivo in the isolated colonic subepithelial myofibroblasts by reverse transcription-quantitative polymerase chain reaction and immunoblot analysis, respectively. The results indicated that triptolide decreased ECM deposition and collagen production in the colon, and inhibited collagen Iα1 transcripts and collagen I protein expression in the isolated subepithelial myofibroblasts of the rats with colonic fibrosis. In conclusion, triptolide ameliorates colonic fibrosis in the experimental rat model, suggesting triptolide may be a promising compound for inflammatory bowel disease treatment. [ABSTRACT FROM AUTHOR]

Objective: This study was designed to identify the effect of rivaroxaban, a direct factor Xa inhibitor, on trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. Materials and Methods: Twenty-four female Wistar rats were divided into 4 groups of 6 each. Group 1 received TNBS + rivaroxaban, group 2 received TNBS + methylprednisolone, group 3 received TNBS and group 4 received a saline enema. Colitis was induced in the rats by the intracolonic administration of TNBS. Rivaroxaban and methylprednisolone were given by oral gavage daily for 7 days. The rats were killed 7 days after the induction of colitis. Results: Rivaroxaban and methylprednisolone significantly reduced gross damage and histopathological scores. Rivaroxaban was more effective than methylprednisolone in terms of microscopic mucosal healing. Rivaroxaban attenuated the accumulation of malonyldialdehyde (MDA) and transforming growth-factor β1 (TGF-β1) and the activites of myeloperoxidase (MPO), matrix metalloproteinase-3 and tissue inhibitor of metalloproteinases-1. Methylprednisolone reduced only the activity of MPO and the accumulation of MDA and TGF-β1. Superoxide dismutase activity showed a restoration to normal levels after rivaroxaban and methylprednisolone administration. Conclusions: Rivaroxaban showed a therapeutic effect in the TNBS model of experimental colitis, and it seemed to be at least as effective as methylprednisolone. This effect may be brought about by the inhibition of oxidative stress and metalloproteinase activity associated with tissue injury and remodeling. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Damage to the enteric nervous system (ENS) associated with intestinal inflammation may underlie persistent alterations to gut functions, suggesting that enteric neurons are viable targets for novel therapies. Mesenchymal stem cells (MSCs) offer therapeutic benefits for attenuation of neurodegenerative diseases by homing to areas of inflammation and exhibiting neuroprotective, anti-inflammatory, and immunomodulatory properties. In culture, MSCs release soluble bioactive factors promoting neuronal survival and suppressing inflammation suggesting that MSC-conditioned medium (CM) provides essential factors to repair damaged tissues. We investigated whether MSC and CM treatments administered by enema attenuate 2,4,6-trinitrobenzene-sulfonic acid (TNBS)-induced enteric neuropathy and motility dys-function in the guinea pig colon. Guinea pigs were randomly assigned to experimental groups and received a single application of TNBS (30 mg/kg) followed by 1 X 106 human bone marrow-derived MSCs, 300 µl CM, or 300 µl unconditioned medium 3 h later. After 7 days, the effect of these treatments on enteric neurons was assessed by histo-logical, immunohistochemical, and motility analyses. MSC and CM treatments prevented inflammation-associated weight loss and gross morphological damage in the colon; decreased the quantity of immune infiltrate in the colonic wall (P < 0.01) and at the level of the myenteric ganglia (P < 0.001); prevented loss of myenteric neurons (P < 0.05) and damage to nerve processes, changes in ChAT, and nNOS immunoreactivity (P < 0.05); and alleviated inflammation-induced colonic dysmotility (contraction speed; P < 0.001, contractions/min; P < 0.05). These results provide strong evidence that both MSC and CM treatments can effectively prevent damage to the ENS and alleviate gut dysfunction caused by TNBS-induced colitis. [ABSTRACT FROM AUTHOR]

Ulcerative colitis and Crohn's disease are a set of chronic, idiopathic, immunological and relapsing inflammatory disorders of the gastrointestinal tract referred to as inflammatory bowel disorder (IBD). Although the etiological factors involved in the perpetuation of IBD remain uncertain, development of various animal models provides new insights to unveil the onset and the progression of IBD. Various chemical-induced colitis models are widely used on laboratory scale. Furthermore, these models closely mimic morphological, histopathological and symptomatical features of human IBD. Among the chemical-induced colitis models, trinitrobenzene sulfonic acid (TNBS)-induced colitis, oxazolone induced-colitis and dextran sulphate sodium (DSS)-induced colitis models are most widely used. TNBS elicits Th-1 driven immune response, whereas oxazolone predominantly exhibits immune response of Th-2 phenotype. DSS-induced colitis model also induces changes in Th-1/Th-2 cytokine profile. The present review discusses the methodology and rationale of using various chemical-induced colitis models for evaluating the pathogenesis of IBD. [ABSTRACT FROM AUTHOR]

Objective: This study was aimed to investigate the beneficial effects of quercetin (QCT) against trinitrobenzene sulfonic acid (TNBS) induced clinical, morphological, and biochemical alterations in rats. Materials and Methods: Colitis in rats was induced by administration of TNBS (25 mg dissolved in 0.25 ml of 30% ethanol) 8 cm into the rectum of the rat using a catheter. The animals were divided into six experimental groups (n = 6); naive (saline only without TNBS administration), control (saline + TNBS), standard (sulfasalazine 25 mg/kg + TNBS), QCT (25) (QCT 25 mg/kg + TNBS), QCT (50) (QCT 50 mg/kg + TNBS), QCT (100) (QCT 100 mg/kg + TNBS). Sulfasalazine (25 mg/kg) and QCT (25, 50 and 100 mg/kg) were administered per oral for 11 days and the colonic damage was evaluated in terms of macroscopical (body weight, stool consistency, rectal bleeding, and ulcer index) and biochemical parameters (myeloperoxidase activity, lipid peroxidation, nitrite, and glutathione). Results: Treatment with QCT (50, 100 mg/kg) for 10 days following TNBS administration significantly attenuated the clinical, morphological, and biochemical alterations induced by TNBS, whereas it was found to be not effective at its lower dose (25 mg/kg) throughout the experimental protocol. Conclusion: QCT attenuates the clinical, morphological and biochemical alterations induced by TNBS possibly via its antioxidant mechanism. [ABSTRACT FROM AUTHOR]

Highlights: [•] Grape juice exerts anti-inflammatory potential against colitis. [•] Grape juice decreases TNF-alpha expression. [•] Grape juice may be a suitable agent against inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

We evaluated the effects of sodium alginate (AL-Na) on dextran sulfate sodium (DSS)- and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. DSS was added to the drinking water for 7 days. In another experiment, DSS was added to the drinking water for 5 days and DSS-free water was provided thereafter. In a separated study, colitis was induced by intrarectally administered TNBS. AL-Na, 5-aminosalicylic acid, or prednisolone was orally administered. These colitis models exhibited colonic damage and produced noticeable inflammatory responses and aggravated goblet cell damage. AL-Na significantly ameliorated DSS- and TNBS-induced experimental colitis and prevented goblet cell damage. Prednisolone also suppressed colitis but caused loss of body and spleen weight. In contrast, AL-Na did not provoke these symptoms. These data suggest that AL-Na may be a possible therapeutic agent for the treatment of inflammatory bowel disease. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Background: Propolis is a resinous substance collected by honeybees from leaf buds and cracks in the bark of various plants. We previously demonstrated the inhibitory activity of Brazilian propolis ethanolic extract against the differentiation process of Th17 cells and pathogenesis of collagen-induced arthritis, which is an experimental animal model of rheumatoid arthritis. Th1 cells are also involved in several autoimmune and inflammatory diseases, such as inflammatory bowel disease. In the present study, we demonstrated for the first time that Brazilian propolis significantly inhibited the generation of Th1 cells. Furthermore, we hypothesized that the administration of propolis to a murine model of colitis would suppress Th1 cell differentiation and ultimately ameliorate colitis. Materials and methods: CD4 T cells were stimulated under Th1-polarizing conditions (immobilized anti-CD3 and anti-CD28 antibodies with IL-12 plus an anti-IL-4 monoclonal antibody for 5days) with or without the propolis ethanolic extract. Cells were characterized for helper T cell subsets by flow cytometric analysis. Furthermore, we investigated the effects of propolis on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in a mouse model. Results: Propolis dose-dependently reduced the frequency of IFNγ-producing CD4 T cells under Th1-polarizing conditions. Furthermore, the inhibitory effect of propolis on Th1 differentiation was demonstrated in vivo. The severity of colitis in mice fed propolis was significantly lower than that of mice fed the control diet. Conclusion: These findings suggest that the suppressive effect of Brazilian propolis on Th1 differentiation may be useful in controlling unbalanced cytokine networks in autoimmune diseases. [Copyright &y& Elsevier]

Efficacy of probiotics in the management of human inflammatory bowel disease (IBD) has been approved in the recent years. In the present work, the efficacy of a new biodegradable nanoparticles (NPs) of encapsulated and lyophilized probiotic extract (LPE) was examined in murine colitis. Colitis was induced by rectal instillation of trinitrobenzen sulfonic acid to male Wistar rats. The safety and effective dose of LPE was determined in a pilot study. To ease delivery into colon, LPE was encapsulated in chitosan-coated-poly (lactide co glycolide acid) NPs. After induction of colitis, animals in different groups received test compound in three doses by gavage for 10 days. Groups of sham, control (saline), and standard (dexamethasone) were also assigned. Colonic pathological examination, tumor necrosis factor alpha, interlukin (IL)-1β, myeloperoxidase (MPO), and lipid peroxidation (LPO) were performed. LPE at all doses (273, 545, and 1100 mg/kg) had positive effects in reduction of pro-inflammatory cytokines, LPO, and MPO in a dose-dependent manner. The formulated compound containing medium dose of LPE was more efficient in mitigating the experimental colitis in comparison with that of high-dose LPE. It is concluded that LPE and its nanoparticle-encapsulated form are very much effective in control of colitis. Regarding safety of this compound, further studies can be conducted in patients with IBD. [ABSTRACT FROM AUTHOR]

Background/Aims: Compounds of Cannabis sativa are known to exert anti-inflammatory properties, some of them without inducing psychotropic side effects. Cannabidiol (CBD) is such a side effect-free phytocannabinoid that improves chemically induced colitis in rodents when given intraperitoneally. Here, we tested the possibility whether rectal and oral application of CBD would also ameliorate colonic inflammation, as these routes of application may represent a more appropriate way for delivering drugs in human colitis. Methods: Colitis was induced in CD1 mice by trinitrobenzene sulfonic acid. Individual groups were either treated with CBD intraperitoneally (10 mg/kg), orally (20 mg/kg) or intrarectally (20 mg/kg). Colitis was evaluated by macroscopic scoring, histopathology and the myeloperoxidase (MPO) assay. Results: Intraperitoneal treatment of mice with CBD led to improvement of colonic inflammation. Intrarectal treatment with CBD also led to a significant improvement of disease parameters and to a decrease in MPO activity while oral treatment, using the same dose as per rectum, had no ameliorating effect on colitis. Conclusion: The data of this study indicate that in addition to intraperitoneal application, intrarectal delivery of cannabinoids may represent a useful therapeutic administration route for the treatment of colonic inflammation. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objectives: Iron chelators, such as maltol and kojic acid, have antioxidant and anti-inflammatory properties. They may have beneficial effects on inflammatory bowel disease (IBD) because iron can develop and aggravate inflammation in IBD. In the present study, the effect of selected iron chelators and anti-oxidants were evaluated on a model of trinitrobenzene sulfonic acid (TNBS)-induced colitis. Methods: Colitis was induced with instillation of 75 mg/kg TNBS in 0.25 ml ethanol 50% via the anus in fasted male Wistar rats. The animals were assigned randomly to 12 groups (n = 6) and treated once daily, started 2 hours before colitis induction, with normal saline (5 ml/kg), maltol (70, 140, 280 mg/kg), kojic acid (75, 150, 300 mg/kg), vitamin E (400 mg/kg), deferiprone (L1) (150 mg/kg) and prednisolone (4 mg/kg) orally and deferoxamine (50 mg/kg) intraperitoneally for 5 days. In the sixth day, rats were scarified and colon tissues were assessed macroscopically and pathologically. Results: Maltol (280 mg/kg) was able to reduce colon weight / length ratio, ulcer index and total colitis index similar to prednisolone, deferoxamine and deferiprone as positive controls. However, kojic acid and vitamin E could not significantly alleviate macroscopic and/or pathologic features of inflammation in comparison to normal saline. Conclusions: Maltol with the highest test dose was capable to protect against experimentally induced colitis. Kojic acid and vitamin E were not effective in this animal model of colon inflammation. More detailed studies are warranted to explore the mechanisms involved in anti-colitic property of maltol and to explain ineffectiveness of kojic acid and vitamin E. [ABSTRACT FROM AUTHOR]

Background: Mesenchymal stem cells have potential applications in inflammatory bowel disease due to their immunomodulatory properties. Our aim was to evaluate the feasibility, safety and efficacy of endoscopic administration of adipose-derived mesenchymal stem cells (ASCs) in a colitis model in rats. Methods: Colitis was induced in rats by rectal trinitrobenzenesulfonic acid (TNBS). After 24 h ASCs (107 cells) or saline vehicle were endoscopically injected into the distal colon. Rats were followed for 11 days. Daily weight, endoscopic score at days 1 and 11, macroscopic appearance at necropsy, colon length and mRNA expression of Foxp3 and IL-10 in mesenteric lymph nodes (MLN) were analyzed. Results: Endoscopic injection was successful in all the animals. No significant adverse events or mortality due to the procedure occurred. Weight evolution was significantly better in the ASC group, recovering initial weight by day 11 (− 0.8% ± 10.1%, mean ± SD), whereas the vehicle group remained in weight loss (− 6.7% ± 9.2%, p = 0.024). The endoscopic score improved in the ASC group by 47.1% ± 5.3% vs. 21.8% ± 6.6% in the vehicle group (p < 0.01). Stenosis was less frequent in the ASC group (4.8% vs. 41.2%, p < 0.01). Colon length significantly recovered in the ASC group versus the vehicle group (222.6 ± 17.3 mm vs. 193.6 ± 17.9 mm, p < 0.001). The endoscopic score significantly correlated with weight change, macroscopic necropsy score and colon length. Foxp3 and IL-10 mRNA levels in MLN recovered with ASC treatment. Conclusions: ASC submucosal endoscopic injection is feasible, safe and ameliorates TNBS-induced colitis in rats, especially stenosis. [ABSTRACT FROM AUTHOR]