mocetinostat has been researched along with Colitis* in 849 studies
3 review(s) available for mocetinostat and Colitis
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Antioxidant and anti-inflammatory protective effects of yellowtail (
Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Arginine; Caco-2 Cells; Claudin-4; Colitis; Cyclooxygenase 2; Dextran Sulfate; Humans; Hydrogen Peroxide; Interleukin-1beta; Interleukin-8; Lipopolysaccharides; Mesalamine; Mice; Mice, Inbred C57BL; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Nucleic Acids; Occludin; Peroxidase; Reactive Oxygen Species; Sulfates; Tumor Necrosis Factor-alpha | 2022 |
Assessment of anticolitic drugs in the trinitrobenzene sulfonic acid (TNBS) rat model of inflammatory bowel disease.
Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Arginine; Blotting, Western; Colitis; Disease Models, Animal; Drug Evaluation, Preclinical; Enzyme Inhibitors; Inflammatory Bowel Diseases; Injections, Subcutaneous; Instillation, Drug; Male; Models, Animal; Neutrophils; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2003 |
Flavonoids and arachidonic acid metabolism.
Topics: Acetates; Acetic Acid; Animals; Arachidonic Acid; Arachidonic Acids; Carrageenan; Colitis; Disease Models, Animal; Edema; Flavonoids; Humans; In Vitro Techniques; Lipoxygenase Inhibitors; Peroxidase; Phospholipases A; Pleurisy; Prostaglandin-Endoperoxide Synthases; Quercetin | 1988 |
4 trial(s) available for mocetinostat and Colitis
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Amelioration of experimental colitis by a novel nanoselenium-silymarin mixture.
Silymarin has intracellular antioxidant property and inhibits activation of nuclear factor-κB (NF-κB) in low concentrations and reduces tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6 levels, cyclooxygenase (COX), and angiogenesis. Selenium is one of the necessary trace element nutrients for human and animals. Selenium nanoparticles (nano-Se) have more bioavailability with less toxicity.. To investigate the combination effect of silymarin and nano-Se on inhibition of NF-κB, proinflammatory cytokines, and oxidative stress biomarkers in the experimental colitis.. Trinitrobenzene sulfonic acid (TNBS) was used to induce colitis. After TNBS instillation, rats were distributed into six groups, containing silymarin and nano-Se alone or in combination, dexamethasone, negative control with no treatment and the last one was normal sham rats. All drugs were administered for 7 days. Colon samples were scored macroscopically and microscopically. The levels of activated NF-κB, IL-1β, TNF-α, myeloperoxidase (MPO), lipid peroxidation, protein carbonyl (PC), and the antioxidant power of the colon homogenates were determined.. A significant decrease in NF-κB activity in treated groups was observed. The levels of TNF-α, IL-1β, MPO, lipid peroxidation, and PC were reduced and an improvement in antioxidant power of treated groups was seen. Combination of silymarin and nano-Se were more effective than each one alone in improvement of NF-κB, TNF-α, antioxidant power, and lipid peroxidation values, although this difference was not significant in other factors.. Co-administration of silymarin and nano-Se with a good antioxidant profile and inhibition of NF-κB is a possible candidate for better management of inflammatory bowel disease. Topics: Animals; Antioxidants; Biomarkers; Colitis; Colon; Disease Models, Animal; Interleukin-1beta; Lipid Peroxidation; Male; Nanoparticles; NF-kappa B; Oxidative Stress; Peroxidase; Protein Carbonylation; Rats; Rats, Wistar; Selenium; Silymarin; Tumor Necrosis Factor-alpha | 2011 |
Pulsatile systems for colon targeting of budesonide: in vitro and in vivo evaluation.
The purpose of this study is to increase the lag time and prevent release of budesonide, a corticosteroid drug used in Crohn's disease for the first 5 h and efficiently deliver it to the colon. Eudragit S100 spray-coated capsules and pulsatile systems using tablet plugs of cellulose acetate butyrate (CAB), HPMC K4M, guar gum, and pectin were prepared. Eudragit S100-coated capsules released 80.62% after 5 h. In pulsatile systems, decreasing the ratio of the polymer significantly increased the rate and extent of drug release. Spray-coating with EUD S100 decreased the extent of drug release to 48.41%, 69.94%, 80.58%, and 45.23% in CAB, HPMC K4M, pectin, and guar gum, respectively; however, the entire amount was released in the target area. In the presence of bacterial enzymes, selected formulas showed nearly 100% release. X-ray imaging performed to monitor the capsules throughout the GIT in human volunteers of the capsules and spray-coated pulsatile systems with 25% guar gum in the plug showed bursting in the transverse and ascending colon, respectively. Both formulations showed marked reduction in induced rabbit colitis model. Topics: Administration, Oral; Adult; Animals; Biological Availability; Budesonide; Capsules; Cellulose; Chemistry, Pharmaceutical; Colitis; Colon; Colon, Transverse; Delayed-Action Preparations; Galactans; Gastric Mucosa; Humans; Hydrogen-Ion Concentration; Hypromellose Derivatives; Ileum; Lactose; Male; Mannans; Mannosidases; Methylcellulose; Pectins; Peroxidase; Plant Gums; Polygalacturonase; Polymethacrylic Acids; Rabbits; Radiography; Rectum; Stomach; Tablets; Trinitrobenzenesulfonic Acid; Young Adult | 2011 |
Effect of argatroban on trinitrobenzene sulfonic acid-induced colitis.
Recent studies have suggested that heparin is effective for treatment of inflammatory bowel disease (IBD) and its various effects (in addition to the anticoagulant effect). We evaluated the effects of argatroban as an antithrombin drug on trinitrobenzene sulfonic acid (TNB)-induced colitis, an established model of IBD.. Rats were randomly assigned to four groups in which mini-osmotic pumps containing saline (TNB-S), argatroban (TNB-A), or 100 U/kg heparin (TNB-H) were intraperitoneally implanted. Three days after the pumps were implanted, TNB was infused via the anus, and colitis was induced. After 5 days, prothrombin time (PT), activated partial prothrombin time (APTT), antithrombin III (AT-III), platelet, fibrinogen, colonic wet weight, macroscopic damage score, histological score, mucosal myeloperoxidase activity and mucosal leukotrien B4 (LTB4) levels were compared among the four groups.. The APTT was prolonged in the heparin treatment group but only slightly prolonged in the argatroban treatment group. The platelet count and the fibrinogen level were higher in the TNB-S group than in the healthy control group and the AT-III level was slightly lower in the TNB-S group than in the healthy control group and lower still in the TNB-H group.. The colonic wet weight was similar among the four groups while the macroscopic damage score, histological score, mucosal myeloperoxidase activity and the mucosal LTB4 level were significantly decreased in the TNB-A and TNB-H groups. Argatroban, as well as heparin may be effective for treatment of TNB-induced colitis. Topics: Analysis of Variance; Animals; Antithrombins; Arginine; Blood Coagulation Tests; Colitis; Disease Models, Animal; Heparin; Immunoenzyme Techniques; Infusion Pumps, Implantable; Leukotriene B4; Male; Nitrobenzenes; Peroxidase; Pipecolic Acids; Rats; Rats, Wistar; Sulfonamides; Sulfonic Acids | 2000 |
Butyrate enema therapy stimulates mucosal repair in experimental colitis in the rat.
The short chain fatty acid (SCFA) butyrate provides energy for colonocytes, stimulates colonic fluid and electrolyte absorption and is recognised as an effective treatment for multiple types of colitis.. To examine the impact of butyrate enema therapy on the clinical course, severity of inflammation, and SCFA stimulated Na+ absorption in a chronic experimental colitis.. Distal colitis was induced in rats with a trinitrobenzenesulphonic acid (TNBS) enema. Five days after induction, rats were divided into groups to receive: no treatment, saline enemas, or 100 mM Na-butyrate enemas daily. On day 24, colonic damage score and tissue myeloperoxidase (MPO) activity were evaluated. Colon was mounted in Ussing chambers and Na+ transport and electrical activities were measured during a basal period and after stimulation with 25 mM butyrate.. In the untreated and the saline enema treated TNBS groups, diarrhoea and extensive colonic damage were seen, associated with increased tissue MPO activities and absent butyrate stimulated Na+ absorption. In contrast, in the butyrate enema treated TNBS group, diarrhoea ceased, colonic damage score improved, and tissue MPO activity as well as butyrate stimulated Na+ absorption recovered to control values.. Butyrate enema therapy stimulated colonic repair, as evidenced by clinical recovery, decreased inflammation, and restoration of SCFA stimulated electrolyte absorption. Topics: Animals; Butyrates; Colitis; Colon; Disease Models, Animal; Enema; Ion Transport; Male; Mucous Membrane; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 1996 |
842 other study(ies) available for mocetinostat and Colitis
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A Chemically Induced Experimental Colitis Model with a Simple Combination of Acetic Acid and Trinitrobenzene Sulphonic Acid.
It was aimed to induce a new experimental colitis model by using acetic acid and trinitrobenzene sulphonic acid together and to investigate the severity of inflammation biochemically and histopathologically in comparison with other models.. Fifty-six Wistar albino male rats were randomly divided into 4 groups as control, acetic acid, trinitrobenzene sulphonic acid, and combined groups, and the animals were sacrificed following the induction of colitis on the third day and on the seventh day. The serum amyloid A and myeloperoxidase were tested in plasma samples, and the tumor necrosis factor-alpha, interleukin 33, and ST2 were assayed in colon tissue samples with enzyme-linked immunosorbent assay in addition to histopathological examination.. There were statistically significant differences between the combined and the control groups both on the third day and on the seventh day in all parameters. There was no difference between the acetic acid group on the seventh day and the control groups in biochemical parameters.. The acetic acid model forms acute colitis. The combined model is found to be more successful in forming inflammation when compared to other models. Topics: Acetic Acid; Animals; Colitis; Colon; Inflammation; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2023 |
Neuropeptide W Exhibits Preventive and Therapeutic Effects on Acetic Acid-Induced Colitis via Modulation of the Cyclooxygenase Enzyme System.
The novel peptide neuropeptide W (NPW) was originally shown to function in the control of feeding behavior and energy homeostasis. The aim of this study was to elucidate the putative preventive and therapeutic effects of NPW on colitis-associated oxidative injury and the underlying mechanisms for its action.. Sprague-Dawley rats in the acute colitis groups received NPW (0.5, 1 or 5 µg/kg/day) injections prior to induction of colitis with acetic acid, while the chronic colitis groups were treated after the induction of colitis. In both acute and chronic colitis (CC) groups, treatments were continued for 5 days and the rats were decapitated at the 24th hour of the last injections and colon tissues were collected for assessments.. NPW pretreatment given for 5 days before colitis induction, as well as treating rats with NPW during the 5-day course of CC, abolished colonic lipid peroxidation. NPW treatment prevented colitis-induced reduction in blood flow, diminished neutrophil infiltration, and pro-inflammatory cytokine responses. NPW pretreatment only at the higher dose reduced colonic edema and microscopic score and preserved colonic glutathione stores. Elevations in cyclooxygenase (COX) enzyme activity and COX-1 protein level during the acute phase of colitis as well as reduction in COX-2 were all reversed with NPW pretreatment. In contrast, NPW treatment was effective in reducing the elevated COX-2 concentration during the chronic phase.. NPW alleviates acetic acid-induced oxidative colonic injury in rats through the upregulation of colonic blood flow as well as the inhibition of COX-2 protein expression and pro-inflammatory cytokine production. Topics: Acetic Acid; Animals; Colitis; Colon; Cyclooxygenase 2; Cytokines; Neuropeptides; Peroxidase; Rats; Rats, Sprague-Dawley | 2023 |
Anti-inflammatory activity of novel derivatives of pyrazolo [3,4d] pyridazine against digestive system inflammation.
The digestive system is exposed to severe inflammation as a result of taking some medications that have gastrointestinal side effects. Sixty Swiss-albino male mice were randomly distributed into six groups to treat inflammations of the colon, stomach, and small intestine caused by taking high doses of diclofenac (D), with two novel synthesized compounds, pyrazolo [3,4 d] pyridazine derivatives (Co1 and Co2). Myeloperoxidase enzyme activity was determined in the colon and small intestinal tissues. Serum contents of TNF-α, IL-22, IgG, and IgM were determined by ELISA. Histopathological examinations of the colon, small intestinal, and stomach tissues were microscopically analyzed. TNF-α, IL-22, and TNFSF11 gene expression were measured in the colon, intestinal, and spleen using qRT-PCR. Diclofenac caused surface columnar epithelial cell loss, focal necrosis of the gastric mucosa, inflammatory cell infiltration, and congested blood vessels in the stomach, colon, and small intestinal tissues. Co1 component was found to be better than Co2 component in reducing the focal necrosis of gastric mucosa and improving the histological structures of the stomach, colon, and small intestinal tissues. After 14 days, the activity of the myeloperoxidase enzyme was increased in group D and decreased in groups DCo1, DCo2, Co1, and Co2. Serum concentrations of TNF-α and IgG were increased, while IL-22 and IGM were reduced in the D, DCo1, and DCo2 groups compared with the Co1 and control groups. TNF-α gene was upregulated in the D group and downregulated in the Co1 group, while the IL-22 gene was downregulated in the D group and upregulated in the Co1 group compared with the control group. The CO1 component may be useful in reducing digestive system inflammation. Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Carbon Dioxide; Colitis; Colon; Diclofenac; Disease Models, Animal; Immunoglobulin G; Immunoglobulin M; Inflammation; Intestinal Mucosa; Mice; Necrosis; Peroxidase; Tumor Necrosis Factor-alpha | 2023 |
Aurozyme: A Revolutionary Nanozyme in Colitis, Switching Peroxidase-Like to Catalase-Like Activity.
A therapeutic strategy that could address colitis of multiple etiologies while restoring the dysbiosis of gut microbiota is attractive. Here, Aurozyme, a novel nanomedicine comprised of gold nanoparticles (AuNPs) and glycyrrhizin (GL) with a glycol chitosan coating layer, as a promising approach for colitis, is demonstrated. The unique feature of Aurozyme is the conversion of harmful peroxidase-like activity of AuNPs to beneficial catalase-like activity due to the amine-rich environment provided by the glycol chitosan. This conversion process enables Aurozyme to oxidize the hydroxyl radicals derived from AuNP, producing water and oxygen molecules. In fact, Aurozyme effectively scavenges reactive oxygen/reactive nitrogen species (ROS/RNS) and damage-associated molecular patterns (DAMPs), which can attenuate the M1 polarization of macrophage. It exhibits prolonged adhesion to the lesion site, promoting sustained anti-inflammatory effects and restoring intestinal function in colitis-challenged mice. Additionally, it increases the abundance and diversity of beneficial probiotics, which are essential for maintaining microbial homeostasis in the gut. The work highlights the transformative potential of nanozymes for the comprehensive treatment of inflammatory disease and represents an innovative switching technology of enzyme-like activity by Aurozyme. Topics: Animals; Antioxidants; Catalase; Colitis; Gold; Metal Nanoparticles; Mice; Oxygen; Peroxidase; Reactive Oxygen Species | 2023 |
Role of cyclooxygenases 1 and 2 in the maintenance of colonic mucosal integrity in an experimental colitis model.
The role of cyclooxygenase (COXs) isoforms in maintaining colonic mucosal integrity is not fully understood. This study aimed to evaluate the role of COX-1 and -2 on colonic mucosal integrity in an experimental colitis model. Colitis was induced in Wistar rats by intracolonic administration of 2,4,6-trinitrobenzenesulfonic acid (20 mg + 50% ethanol). The control group (sham group) received saline only. After 7, 14, or 28 days, colonic samples were removed, and macroscopic lesion scores, wet weight, myeloperoxidase activity, and transepithelial electrical resistance (TER) were determined. In other rat groups, colonic samples from the sham group and a 7th day post-colitis group were mounted in Üssing chambers with the luminal side exposed to a buffer solution (control), acetylsalicylic acid (ASA), SC-560 (COX-1 inhibitor), or celecoxib (COX-2 inhibitor). TER and epithelial permeability to fluorescein were measured. The 7th day colitis group had higher macroscopic damage scores, wet weight, and myeloperoxidase activity and lower basal TER than the sham, 14th day colitis, and 28th day colitis groups. Inhibition of COX-1 but not COX-2 significantly decreased TER and increased permeability to fluorescein in the 7th day post-colitis group compared to the sham group. Additionally, ASA decreased the colonic mucosal integrity on day seven post-colitis compared to the sham group. A decrease in the colonic mucosa integrity in the experimental colitis model can be aggravated only by the inhibition of COX-1, which demonstrated the importance of this enzyme in the maintenance of colonic mucosal integrity. Topics: Animals; Aspirin; Colitis; Cyclooxygenase 2; Fluoresceins; Intestinal Mucosa; Peroxidase; Rats; Rats, Wistar | 2023 |
Anti-inflammatory Effects of Ivermectin in the Treatment of Acetic Acid-Induced Colitis in Rats: Involvement of GABA
Recent investigations have proposed the potential role of gamma-aminobutyric acid (GABA) in regulating motility and immunity of the gastrointestinal system.. We aimed to investigate the anti-inflammatory effects of ivermectin (IVM) through GABA. In a controlled experimental study, we enrolled 78 male Wistar rats (13 groups; 6 rats/group). After colitis induction using acetic acid (4%), IVM, baclofen (a standard GABA. The greatest recovery was found after administering IVM 0.5, baclofen 0.5, or IVM 0.2 + baclofen 0.2 mg/kg/day (ulcer index [UI] = 1.4 ± 0.4, 1.7 ± 0.6, and 1.4 ± 0.3, respectively; p < 0.001 vs. the control [UI = 6.5 ± 0.7]). Histopathological evaluations revealed a significant decrease in the inflammation severity in the three above-mentioned groups. P-NF-ĸB p65, COX-2, and iNOS expression, MPO activity, and TNF-α levels also decreased dramatically following treatment with IVM 0.5, baclofen 0.5, or the combination therapy (p < 0.001 vs. the control).. IVM exerted promising anti-inflammatory effects in treating acetic acid-induced colitis in rats. Its synergistic effect with baclofen also signified the possible involvement of GABA Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Baclofen; Colitis; Colon; Cyclooxygenase 2; Ivermectin; Male; NF-kappa B; Peroxidase; Rats; Rats, Wistar; Receptors, GABA; Tumor Necrosis Factor-alpha | 2022 |
Rectal roflumilast improves trinitrobenzenesulfonic acid-induced chronic colitis in rats.
Roflumilast, a highly selective oral phosphodiesterase IV inhibitor, exerts anti-inflammatory and anti-fibrotic effects. Oral roflumilast causes gastrointestinal side effects, especially vomiting, which could be reduced by administering roflumilast via off-label routes. Inhaled roflumilast reportedly improved inflammatory and histopathological changes in asthmatic mice. The current study investigated the effects of oral and rectal roflumilast on trinitrobenzenesulfonic acid (TNBS)-induced chronic colitis in rats, an experimental model resembling human Crohn's disease. Five groups of rats (n=8) were used: normal control, TNBS-induced colitis, and three TNBS-treated colitic groups, which received oral sulfasalazine (500 mg·kg-1·day-1), oral roflumilast (5 mg·kg-1·day-1), or rectal roflumilast (5 mg·kg-1·day-1) for 15 days after colitis induction. Then, the following were assessed: the colitis activity score, tumor necrosis factor (TNF)-α, interleukin (IL)-2, and IL-6 serum levels, colonic length, and myeloperoxidase, malonaldehyde, and glutathione levels. Histological examinations employed H&E, Masson trichrome, and PAS stains in addition to immunostaining for KI-67 and TNF-α. The TNBS-induced colitis rats showed significant increases in disease activity scores, serum TNF-α, IL-2, and IL-6 levels, and colonic myeloperoxidase and malonaldehyde content. They also showed significant decreases in colonic length and glutathione levels in addition to histopathological and immunohistochemical changes. All the treatments significantly improved all these changes. Sulfasalazine provided the greatest improvement, followed by oral roflumilast, and then rectal roflumilast. In conclusion, both oral and rectal roflumilast partially improved TNBS-induced chronic colitis, suggesting the potential of roflumilast as an additional treatment for Crohn's disease. Topics: Aminopyridines; Animals; Benzamides; Colitis; Cyclopropanes; Disease Models, Animal; Mice; Peroxidase; Rats; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2022 |
Deficiency in glutathione synthesis and reduction contributes to the pathogenesis of colitis-related liver injury.
Liver disease is the most common extra-intestinal manifestation of ulcerative colitis (UC), but the underlying pathogenesis is still not clarified. It is well accepted that the occurrence of UC-related liver disease has close correlation with immune activation, intestinal bacterial liver translocation, inflammatory cytokine storm, and the disturbance of bile acid circulation. The occurrence of UC-related liver disease makes the therapy difficult, therefor study on the pathogenesis of UC-related liver injury is of great significance for its prevention and treatment. Glutathione (GSH) shows multiple physiological activities, such as free radical scavenging, detoxification metabolism and immune defense. The synthesis and the oxidation-reduction all contribute to GSH antioxidant function. It is reported that the deficiency in hepatic GSH antioxidant function participates in multiple liver diseases, but whether it participates in the pathogenesis of UC-related liver injury is still not clear. This study aims to investigate the feature and underlying mechanism of GSH synthesis and oxidation-reduction function during the development of UC, which will provide useful information for the pathogenesis study on UC-related liver injury.. UC model was induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS)-ethanol solution (5 mg/0.8 mL per rat, 50% ethanol) via intra-colonic administration in rats, and the samples of serum, liver, and colon tissue of rats were collected at the 3rd, 5th, and 7th days post TNBS. The severity degree of colitis was evaluated by measuring the disease activity index, colonic myeloperoxidase activity, and histopathological score, and the degree of liver injury was evaluated by histopathological score and the serum content of alanine aminotransferase. Spearman correlation analysis was also conducted between the degree of colonic lesions and index of hepatic histopathological score as well as serum aspartate aminotransferase level to clarify the correlation between liver injury and colitis. To evaluate the hepatic antioxidant function of GSH in UC rats, hepatic GSH content, enzyme activity of GSH peroxidase (GSH-Px), and GSH reductase (GR) were determined in rats at the 3rd, 5th, and 7th days post TNBS, and the protein expressions of glutamine cysteine ligase (GCL), GSH synthase, GSH-Px, and GR in the liver of UC rats were also examined by Western blotting.. Compared with the control, the disease activity index, colonic myeloperoxidase activity, and histopathological score were all significantly increased at the 3rd, 5th, and 7th days post TNBS (all. There is a significant positive correlation between the degree of liver injury and the severity of colonic lesions, and the occurrence of reduced hepatic GSH synthesis and decreased GSH reduction function is obviously earlier than that of the liver injury in UC rats. The reduced hepatic expression of enzymes that responsible for GSH synthesis and reduction may contribute to the deficiency of GSH synthesis and oxidation-reduction function, indicating that the deficiency in GSH antioxidant function may participate in the pathogenesis of UC related liver injury. Topics: Animals; Antioxidants; Aspartate Aminotransferases; Colitis; Colitis, Ulcerative; Colon; Glutathione; Liver; Peroxidase; Rats; Trinitrobenzenesulfonic Acid | 2022 |
Fermented camel's milk has various health beneficial prebiotics and probiotics. This study aimed to evaluate the preventive efficacy of Topics: Animals; Bacillus amyloliquefaciens; Camelus; Colitis; Colon; Cytokines; Disease Models, Animal; Mice; Milk; Peroxidase; Proliferating Cell Nuclear Antigen; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2022 |
Lycopodium Mitigates Oxidative Stress and Inflammation in the Colonic Mucosa of Acetic Acid-Induced Colitis in Rats.
Inflammatory bowel diseases (IBDs) such as ulcerative colitis (UC) and Crohn's disease (CD) are diseases of the gastrointestinal system involving genetic and environmental factors attributed to oxidative stress and inflammation. Targeting oxidative stress and inflammation by novel dietary compounds of natural origin convincingly appears to be one of the important therapeutic strategies to keep the disease in remission. As there is no permanent cure for IBD except for chronic long-term treatment or surgery, it is therefore imperative to investigate plant-based agents that are receiving attention for their therapeutic benefits to overcome the debilitating clinical conditions of IBD. Lycopodium (LYCO), a plant of tropical and subtropical origin and known by numerous names such as ground pine, club moss, or devil's claw, has been popularly used for centuries in traditional medicine including Chinese and Indian medicines. In the present study, the effect of LYCO has been investigated in an acetic acid (AA)-induced colitis model in Wistar rats. LYCO was orally administered at the dose of 50 mg/kg/day either 3 days before or 30 min after the induction of IBD and continued for 7 days by intrarectal administration of AA. The changes in body weight and macroscopic and microscopic analysis of the colon of rats of different experimental groups were observed on days 0, 2, 4, and 7. The levels of myeloperoxidase (MPO), reduced glutathione (GSH), and malondialdehyde (MDA) were measured. AA caused a significant reduction in body weight and increased macroscopic and microscopic ulcer scores along with a significant decline in antioxidant enzymes, superoxide dismutase (SOD), and catalase and antioxidant substrate, glutathione (GSH). There was a concomitant increased formation of malondialdehyde (MDA), a marker of lipid peroxidation, and raised myeloperoxidase (MPO) activity, a marker of neutrophil activation. Treatment with LYCO significantly improved IBD-induced reduction in body weight, improved histology, inhibited MDA formation, and restored antioxidants along with reduced MPO activity. AA also caused the release of proinflammatory cytokines such as interleukin-1β (IL-1β) and interleukin-23 (IL-23). Furthermore, AA also increased the levels of calprotectin, a protein released by neutrophils under inflammatory conditions of the gastrointestinal tract. LYCO treatment significantly reduced the release of calprotectin and proinflammatory cytokines. The results demonstrate Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Body Weight; Colitis; Colitis, Ulcerative; Cytokines; Glutathione; Inflammation; Inflammatory Bowel Diseases; Intestinal Mucosa; Leukocyte L1 Antigen Complex; Lycopodium; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Wistar | 2022 |
Olmesartan medoxomil self-microemulsifying drug delivery system reverses apoptosis and improves cell adhesion in trinitrobenzene sulfonic acid-induced colitis in rats.
Topics: Animals; Apoptosis; bcl-2-Associated X Protein; Cadherins; Caspase 3; Cell Adhesion; Colitis; Crohn Disease; Drug Delivery Systems; Interleukin-6; Malondialdehyde; Matrix Metalloproteinase 9; Olmesartan Medoxomil; Peroxidase; Rats; Sulfasalazine; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2022 |
Cysteine protease of Clonorchis sinensis alleviates DSS-induced colitis in mice.
Currently, inflammatory bowel disease (IBD) has become a global chronic idiopathic disease with ever-rising morbidity and prevalence. Accumulating evidence supports the IBD-hygiene hypothesis that helminths and their derivatives have potential therapeutic value for IBD. Clonorchis sinensis (C. sinensis) mainly elicit Th2/Treg-dominated immune responses to maintain long-term parasitism in the host. This study aimed to evaluate the therapeutic effects of cysteine protease (CsCP) and adult crude antigen (CsCA) of C. sinensis, and C. sinensis (Cs) infection on DSS-induced colitis mice.. BALB/c mice were given 5% DSS daily for 7 days to induce colitis. During this period, mice were treated with rCsCP, CsCA or dexamethasone (DXM) every day, or Cs infection which was established in advance. Changes in body weight, disease activity index (DAI), colon lengths, macroscopic scores, histopathological findings, myeloperoxidase (MPO) activity levels, regulatory T cell (Treg) subset levels, colon gene expression levels, serum cytokine levels, and biochemical indexes were measured.. Compared with Cs infection, rCsCP and CsCA alleviated the disease activity of acute colitis more significant without causing abnormal blood biochemical indexes. In comparison, rCsCP was superior to CsCA in attenuating colonic pathological symptoms, enhancing the proportion of Treg cells in spleens and mesenteric lymph nodes, and improving the secretion of inflammatory-related cytokines (e.g., IL-2, IL-4, IL-10 and IL-13) in serum. Combined with RNA-seq data, it was revealed that CsCA might up-regulate the genes related to C-type lectin receptor and intestinal mucosal repair related signal pathways (e.g., Cd209d, F13a1 and Cckbr) to reduce colon inflammation and benefit intestinal mucosal repair. Dissimilarly, rCsCP ameliorated colitis mainly through stimulating innate immunity, such as Toll like receptor (TLR) signaling pathway, down-regulating the expression of inflammatory cytokines (e.g., IL-12b, IL-23r and IL-7), thereby restraining the differentiation of Th1/Th17 cells.. Both rCsCP and CsCA showed good therapeutic effects on the treatment of acute colitis, but rCsCP is a better choice. rCsCP is a safe, effective, readily available and promising therapeutic agent against IBD mainly by activating innate immunity and regulating the IL-12/IL-23r axis. Topics: Animals; Clonorchis sinensis; Colitis; Colon; Cysteine Proteases; Cytokines; Dexamethasone; Dextran Sulfate; Disease Models, Animal; Inflammatory Bowel Diseases; Interleukin-10; Interleukin-12; Interleukin-13; Interleukin-2; Interleukin-4; Interleukin-7; Lectins, C-Type; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Peroxidase; Toll-Like Receptors | 2022 |
Probiotics have shown good efficacy in the prevention of ulcerative colitis (UC), but the specific mechanism remains unclear. Therefore, shotgun metagenomic and transcriptome analyses were performed to explore the preventive effect of a potential probiotic Topics: Animals; Claudin-1; Claudin-2; Colitis; Colitis, Ulcerative; Colon; Dextran Sulfate; Disease Models, Animal; Gastrointestinal Microbiome; Humans; Intercellular Adhesion Molecule-1; Interleukin-10; Interleukin-6; Lactobacillus plantarum; Mice; Mice, Inbred C57BL; NF-kappa B; Peroxidase; RNA, Messenger; Transforming Growth Factor beta1; Transforming Growth Factor beta2; Tumor Necrosis Factor-alpha | 2022 |
Improvement of Ulcerative Colitis by Aspartate via RIPK Pathway Modulation and Gut Microbiota Composition in Mice.
The intestine requires a great deal of energy to maintain its health and function; thus, energy deficits in the intestinal mucosa may lead to intestinal damage. Aspartate (Asp) is an essential energy source in the intestinal mucosa and plays a vital part in gut health. In the current study, we hypothesized that dietary supplementation of Asp could alleviate DSS-induced colitis via improvement in the colonic morphology, oxidative stress, cell apoptosis, and microbiota composition in a mouse model of dextran. Asp administration decreased the disease activity index, apoptosis, myeloperoxidase, eosinophil peroxidase, and proinflammatory cytokine (IL-1β and TNF-α) concentrations in the colonic tissue, but improved the body weight, average daily food intake, colonic morphology, and antioxidant-related gene (GPX1 and GPX4) expression in DSS-treated mice. Expression levels of RIPK1 and RIPK3 were increased in the colon following Asp administration in the DSS-induced mice, whereas the MLKL protein expression was decreased. 16S rRNA sequencing showed that Asp treatment increased the abundance of Topics: Animals; Antioxidants; Aspartic Acid; Colitis; Colitis, Ulcerative; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Eosinophil Peroxidase; Gastrointestinal Microbiome; Mice; Mice, Inbred C57BL; Peroxidase; RNA, Ribosomal, 16S; Tumor Necrosis Factor-alpha | 2022 |
Regulation of the Gut Microbiota and Inflammation by β-Caryophyllene Extracted from Cloves in a Dextran Sulfate Sodium-Induced Colitis Mouse Model.
Ulcerative colitis is an inflammatory bowel disease characterized by symptoms such as abdominal pain, diarrhea, bleeding, and weight loss. Ulcerative colitis is typically treated with anti-inflammatory drugs; however, these drugs are associated with various side effects, limiting their use. β-Caryophyllene (BCP), a natural compound derived from cloves, has antioxidant, antibacterial, and anti-inflammatory activities. In this study, we aimed to investigate the effects of BCP on colitis in a dextran sulfate sodium (DSS)-induced colitis mouse model. BCP was administered for seven days, followed by 2.5% DSS for additional seven days to induce colitis. Changes in stool weight, recovery of gut motility, colon length, colon histology, myeloperoxidase activity, inflammatory cytokines (TNF-α, IL-1β, IL-6, IgA, and IgG), and the gut microbiota were observed. Administration of BCP increased stool weight, restored gut motility, and considerably increased colon length compared to those in the untreated colitis mouse model. In addition, the amount of mucin and myeloperoxidase activity in the colon increased, whereas the concentrations of IL-1β, IL-6, and TNF-α decreased following the administration of BCP. Furthermore, BCP reduced the abundance of Proteobacteria which can cause intestinal immune imbalance. These results suggest that BCP has a potential to be developed as a preventive agent for colitis. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colitis, Ulcerative; Dextran Sulfate; Disease Models, Animal; Gastrointestinal Microbiome; Inflammation; Interleukin-6; Mice; Peroxidase; Syzygium; Tumor Necrosis Factor-alpha | 2022 |
Immunomodulatory assessment of Portulaca oleracea L. extract in a mouse model of colitis.
Ulcerative colitis (UC) is a gastrointestinal inflammatory disease with a multifactorial pathophysiology. This study aims to investigate the immunomodulatory effect of Portulaca oleracea leaf ethanolic extract (POE) on acetic acid (AA)-induced UC in mice. Experimental animals received oral doses of POE (200 mg/kg for 7 days) after an induction of colitis by intrarectal AA administration. In mice with AA-induced UC treated with POE, the results revealed a significant modulation in body weight and colon length. Moreover, treatment with POE downregulated the interleukin 1, 6, and 17, tumor necrosis factor-alpha, gamma interferon, and nuclear factor-kappa B levels compared with the colitis group. Furthermore, POE markedly inhibited histological damage, decreased myeloperoxidase activity and reduced fecal calprotectin level compared with the colitis group. These data are consistent with the reduction in total bacterial content in the colon. Taken together, treatment with POE may reduce colonic inflammation by alleviating the immune response and inhibiting the severity of colitis. The HPLC analysis of POE resulted in the identification of seven medicinal compounds comprising two phenolic acids (ferulic and caffeic acids) and five flavonoids (kaempferol, quercetin, rutin, narenginin and hesperidin). Subsequent analysis of POE by GC-MS revealed ten phytocomponents; the major percentages were hexadecenoic acid, methyl ester (29.8119%), α-linolenic acid (25.8431%), 16-octadecenoic acid, methyl ester (15.1578%) and α-tocopherol (10.7848%). Delta-lactams and alkanes were the minor components. Such natural plant-derived substances and their probable synergistic action appear to contribute to a promising therapeutic protocol for colitis. Topics: Animals; Colitis; Cytokines; Disease Models, Animal; Gastrointestinal Microbiome; Immunomodulating Agents; Inflammation Mediators; Leukocyte L1 Antigen Complex; Male; Mice; NF-kappa B; Peroxidase; Phytochemicals; Plant Extracts; Plant Leaves; Portulaca | 2021 |
Characterization of the Synergistic Effect between Ligands of Opioid and Free Fatty Acid Receptors in the Mouse Model of Colitis.
Recent studies suggest that lipids, including free fatty acids (FFAs), are necessary for proper μ opioid receptor (MOR) binding and that activation of opioid receptors (ORs) improves intestinal inflammation. The objective of the study was to investigate a possible interaction between the ORs and FFA receptors (FFARs) ligands in the colitis.. The potential synergistic effect of ORs and FFARs ligands was evaluated using mouse model of acute colitis induced by dextran sulfate sodium (DSS, 4%). Compounds were injected intraperitoneally (i.p.) once or twice daily at the doses of 0.01 or 0.02 mg/kg body weight (BW) (DAMGO-an MOR agonist), 0.3 mg/kg BW (DPDPE-a δ OR (DOR) agonist) and 1 mg/kg BW (naloxone-a non-selective OR antagonist, GLPG 0974-a FFAR2 antagonist, GSK 137647-a FFAR4 agonist and AH 7614-a FFAR4 antagonist) for 4 days.. Myeloperoxidase (MPO) activity was significantly decreased after DAMGO (0.02 mg/kg BW) and GSK 137647 (1 mg/kg BW) administration and co-administration as compared to DSS group.. Treatment with ligands of ORs and FFARs may affect the immune cells in the inflammation; however, no significant influence on the severity of colitis and no synergistic effect were observed. Topics: Aniline Compounds; Animals; Butyrates; Colitis; Disease Models, Animal; Drug Synergism; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; Enkephalin, D-Penicillamine (2,5)-; Inflammation; Ligands; Male; Mice; Mice, Inbred BALB C; Naloxone; Narcotic Antagonists; Peroxidase; Receptors, G-Protein-Coupled; Receptors, Opioid; Receptors, Opioid, delta; Receptors, Opioid, mu; Sulfonamides; Thiophenes; Xanthenes | 2021 |
Terazosin Stimulates Pgk1 to Remedy Gastrointestinal Disorders.
Gastrointestinal disease is the most common health concern that occurs due to environmental, infectious, immunological, psychological, and genetic stress. Among them, the most frequent diseases are gastric ulcer (GU) and ulcerative colitis (UC). DSS-induced UC and ethanol-stimulated GU models resemble the pathophysiology of human gastrointestinal disease. The current study was designed to explore the anti-oxidation, anti-inflammation, anti-cell death properties of terazosin, an α-adrenergic receptor antagonist, in vivo and in vitro. Our results indicate that terazosin dramatically activates Pgk1, and upregulates glycose metabolism, evidenced by the enhanced ATP production and higher LDH enzymatic activity. Also, terazosin significantly enhances p-AKT expression and inhibits NF-κB p65 activation through abrogating the phosphorylation of IKBα, as well as lowers Caspase-1 and GSDMD expression. The findings in this study demonstrate that terazosin exhibits anti-inflammatory effects by downregulating NF-κB-GSDMD signal pathway, along with enhancing glycolysis for gastrointestinal disease treatment. Meanwhile, we also find terazosin ameliorates ethanol-induced gastric mucosal damage in mice. Collectively, as a clinical drug, terazosin should be translated into therapeutics for gastrointestinal disease soon. Topics: Apoptosis; Caco-2 Cells; Cell Survival; Colitis; Cytokines; Deoxyglucose; Dextran Sulfate; Gastric Mucosa; Gastrointestinal Diseases; Glucose; Humans; Hydrogen Peroxide; Inflammation Mediators; Lactic Acid; Malondialdehyde; Models, Biological; Peroxidase; Phosphoglycerate Kinase; Prazosin; Pyroptosis; Stomach Ulcer; Superoxide Dismutase | 2021 |
Novel selective agonist of GPR18, PSB-KK-1415 exerts potent anti-inflammatory and anti-nociceptive activities in animal models of intestinal inflammation and inflammatory pain.
GPR18 is a recently deorphanized receptor which was reported to act with several endogenous cannabinoid ligands. Here, we aimed to describe the role of GPR18 in intestinal inflammation and inflammatory pain.. The anti-inflammatory activity of selective GPR18 agonist, PSB-KK-1415, and antagonist, PSB-CB5, was characterized in semi-chronic and chronic mouse models of colitis induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS). The extent of inflammation was evaluated based on the macroscopic and microscopic scores, quantification of myeloperoxidase (MPO) activity, and Western blot analyses of tumor necrosis factor-α (TNF-α) and interleukin-6 in colonic tissue. The expression of GPR18 in colonic samples from patients with Crohn's disease (CD) was quantified using real-time PCR. The anti-nociceptive potential of the agonist in intestinal inflammation was evaluated in the mouse model of inflammatory pain.. In semi-chronic colitis, PSB-KK-1415 reduced macroscopic score (1.79 ± 0.22 vs. 2.61 ± 0.48), expression of TNF-α (1.89 ± 0.36 vs. 2.83 ± 0.64), and microscopic score (5.00 ± 0.33 vs. 6.45 ± 0.40), all compared to mice with colitis. In chronic colitis, PSB-KK-1415 decreased macroscopic score (3.33 ± 1.26 vs. 4.00 ± 1.32) and MPO activity (32.23 ± 8.51 vs. 41.33 ± 11.64) compared to inflamed mice. In the mouse model of inflammatory pain, PSB-KK-1415 decreased the number of pain-induced behaviors in both, controls (32.60 ± 2.54 vs. 58.00 ± 6.24) and inflamed mice (60.83 ± 2.85 vs. 85.00 ± 5.77) compared to animals without treatment with PSB-KK-1415 (P < 0.005 for both). Lastly, we showed an increased expression of GPR18 in CD patients compared to healthy controls (3.77 ± 1.46 vs. 2.38 ± 0.66, p = 0.87).. We showed that GPR18 is worth considering as a potential treatment target in intestinal inflammation and inflammatory pain. Topics: Adult; Aged; Aged, 80 and over; Animals; Case-Control Studies; Colitis; Crohn Disease; Disease Models, Animal; Female; Humans; Inflammation; Male; Mice; Middle Aged; Nociception; Nociceptive Pain; Peroxidase; Receptors, G-Protein-Coupled | 2021 |
Anti-inflammatory and antibacterial effects of human cathelicidin active fragment KR-12 in the mouse models of colitis: a novel potential therapy of inflammatory bowel diseases.
Inflammatory bowel diseases (IBD) are a group of chronic gastrointestinal tract disorders with complex etiology, with intestinal dysbiosis as the most prominent factor. In this study, we assessed the anti-inflammatory and antibacterial actions of the human cathelicidin LL-37 and its shortest active fragment, KR-12 in the mouse models of colitis.. Mouse models of colitis induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) and dextran sulfate sodium (DSS) were used in the study. The extent of inflammation was evaluated based on the macro- and microscopic scores, quantification of myeloperoxidase (MPO) activity and microbiological analysis of stool samples.. A preliminary study with LL-37 and KR-12 (1 mg/kg, ip, twice daily) showed a decrease in macroscopic and ulcer scores in the acute TNBS-induced model of colitis. We observed that KR-12 (5 mg/kg, ip, twice daily) reduced microscopic and ulcer scores in the semi-chronic and chronic TNBS-induced models of colitis compared with inflamed mice. Furthermore, qualitative and quantitative changes in colonic microbiota were observed: KR-12 (5 mg/kg, ip, twice daily) decreased the overall number of bacteria, Escherichia coli and coli group bacteria. In the semi-chronic DSS-induced model, KR-12 attenuated intestinal inflammation as demonstrated by a reduction in macroscopic score and colon damage score and MPO activity.. We demonstrated that KR-12 alleviates inflammation in four different mouse models of colitis what suggests KR-12 and cathelicidins as a whole are worth being considered as a potential therapeutic option in the treatment of IBD. Topics: Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents; Antimicrobial Cationic Peptides; Cathelicidins; Colitis; Colon; Dextran Sulfate; Feces; Humans; Inflammatory Bowel Diseases; Male; Mice; Mice, Inbred BALB C; Peptide Fragments; Peroxidase; Trinitrobenzenesulfonic Acid | 2021 |
Berberine improves colitis by triggering AhR activation by microbial tryptophan catabolites.
Inflammatory bowel diseases (IBD) are kind of recurrent inflammatory issues that occur in the gastrointestinal tract, and currently clinical treatment is still unideal due to the complex pathogenesis of IBD. Basically, gut barrier dysfunction is triggered by gut microbiota dysbiosis that is closely associated with the development of IBD, we thus investigated the therapeutic capacity of berberine (BBR) to improve the dysregulated gut microbiota, against IBD in rats, using a combinational strategy of targeted metabolomics and 16 s rDNA amplicon sequencing technology. Expectedly, our data revealed that BBR administration could greatly improve the pathological phenotype, gut barrier disruption, and the colon inflammation in rats with dextran sulfate sodium (DSS)-induced colitis. In addition, 16S rDNA-based microbiota analysis demonstrated that BBR could alleviate gut dysbiosis in rats. Furthermore, our targeted metabolomics analysis illustrated that the levels of microbial tryptophan catabolites in the gastrointestinal tract were significantly changed during the development of the colitis in rats, and BBR treatment can significantly restore such changes of the tryptophan catabolites accordingly. At last, our in vitro mechanism exploration was implemented with a Caco-2 cell monolayer model, which verified that the modulation of the dysregulated gut microbiota to change microbial metabolites coordinated the improvement effect of BBR on gut barrier disruption in the colitis, and we also confirmed that the activation of AhR induced by microbial metabolites is indispensable to the improvement of gut barrier disruption by BBR. Collectively, BBR has the capacity to treat DSS-induced colitis in rats through the regulation of gut microbiota associated tryptophan metabolite to activate AhR, which can greatly improve the disrupted gut barrier function. Importantly, our finding elucidated a novel mechanism of BBR to improve gut barrier function, which holds the expected capacity to promote the BBR derived drug discovery and development against the colitis in clinic setting. Topics: Animals; Anti-Inflammatory Agents; Berberine; Caco-2 Cells; Colitis; Colon; Cytokines; Dextran Sulfate; Gastrointestinal Microbiome; Humans; Male; Peroxidase; Rats, Sprague-Dawley; Receptors, Aryl Hydrocarbon; Tryptophan | 2021 |
Rectal administration of carbon monoxide inhibits the development of intestinal inflammation and promotes intestinal wound healing via the activation of the Rho-kinase pathway in rats.
The inhalation of carbon monoxide (CO) gas and the administration of CO-releasing molecules were shown to inhibit the development of intestinal inflammation in a murine colitis model. However, it remains unclear whether CO promotes intestinal wound healing. Herein, we aimed to evaluate the therapeutic effects of the topical application of CO-saturated saline enemas on intestinal inflammation and elucidate the underlying mechanism. Acute colitis was induced with trinitrobenzene sulfonic acid (TNBS) in male Wistar rats. A CO-saturated solution was prepared via bubbling 50% CO gas into saline and was rectally administrated twice a day after colitis induction; rats were sacrificed 3 or 7 days after induction for the study of the acute or healing phases, respectively. The distal colon was isolated, and ulcerated lesions were measured. In vitro wound healing assays were also employed to determine the mechanism underlying rat intestinal epithelial cell restitution after CO treatment. CO solution rectal administration ameliorated acute TNBS-induced colonic ulceration and accelerated ulcer healing without elevating serum CO levels. The increase in thiobarbituric acid-reactive substances and myeloperoxidase activity after induction of acute TNBS colitis was also significantly inhibited after CO treatment. Moreover, the wound healing assays revealed that the CO-saturated medium enhanced rat intestinal epithelial cell migration via the activation of Rho-kinase. In addition, the activation of Rho-kinase in response to CO treatment was confirmed in the inflamed colonic tissue. Therefore, the rectal administration of a CO-saturated solution protects the intestinal mucosa from inflammation and accelerates colonic ulcer healing through enhanced epithelial cell restitution. CO may thus represent a novel therapeutic agent for the treatment of inflammatory bowel disease. Topics: Administration, Rectal; Animals; Carbon Monoxide; Cells, Cultured; Chemokine CXCL1; Colitis; Colon; Inflammation; Intestinal Mucosa; Male; Peroxidase; Rats, Wistar; Re-Epithelialization; rho-Associated Kinases; RNA, Messenger; Signal Transduction; Trinitrobenzenesulfonic Acid; Wound Healing | 2021 |
Anti-Inflammatory Effects of Rosmarinic Acid-Loaded Nanovesicles in Acute Colitis through Modulation of NLRP3 Inflammasome.
Ulcerative colitis (UC), one of the two main types of inflammatory bowel disease, has no effective treatment. Rosmarinic acid (RA) is a polyphenol that, when administered orally, is metabolised in the small intestine, compromising its beneficial effects. We used chitosan/nutriose-coated niosomes loaded with RA to protect RA from gastric degradation and target the colon and evaluated their effect on acute colitis induced by 4% dextran sodium sulphate (DSS) for seven days in mice. RA-loaded nanovesicles (5, 10 and 20 mg/kg) or free RA (20 mg/kg) were orally administered from three days prior to colitis induction and during days 1, 3, 5 and 7 of DSS administration. RA-loaded nanovesicles improved body weight loss and disease activity index as well as increased mucus production and decreased myeloperoxidase activity and TNF-α production. Moreover, RA-loaded nanovesicles downregulated protein expression of inflammasome components such as NLR family pyrin domain-containing 3 (NLRP3), adaptor protein (ASC) and caspase-1, and the consequent reduction of IL-1β levels. Furthermore, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) protein expression increased after the RA-loaded nanovesicles treatment However, these mechanistic changes were not detected with the RA-free treatment. Our findings suggest that the use of chitosan/nutriose-coated niosomes to increase RA local bioavailability could be a promising nutraceutical strategy for oral colon-targeted UC therapy. Topics: Animals; Cinnamates; Colitis; Depsides; Disease Models, Animal; Heme Oxygenase-1; In Vitro Techniques; Inflammasomes; Inflammation; Male; Membrane Proteins; Mice; Mice, Inbred C57BL; Nanomedicine; Nanoparticles; NF-E2-Related Factor 2; NLR Family, Pyrin Domain-Containing 3 Protein; Oxidative Stress; Peroxidase; Rosmarinic Acid; Signal Transduction; Tumor Necrosis Factor-alpha | 2021 |
A case of myeloperoxidase-antineutrophil cytoplasmic antibody and anticardiolipin antibody-positive pyogenic arthritis, pyoderma gangrenosum, acne and hidradenitis suppurativa (PAPASH) syndrome with colitis.
A previous case report of colitis and serine proteinase 3-antineutrophil cytoplasmic antibody positivity in pyogenic arthritis, pyoderma gangrenosum (PG), acne and hidradenitis suppurativa (PAPASH) syndrome with colitis has been published. Herein, we report a similar case of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) positivity. A 26-year-old man presented with recurrent aseptic pyogenic arthritis, acne, hidradenitis suppurativa and PG. Lower gastrointestinal endoscopy was performed, and colitis was observed. No PSTPIP1 gene mutation was found in the gene-sequencing test. Based on these findings and prior case reports, we diagnosed the patient with PAPASH syndrome, a PAPA spectrum disorder complicated by colitis. This patient had PAPASH syndrome with colitis and was MPO-ANCA and anticardiolipin antibodies-positive; it is unclear whether these antibodies play a role in this disease, but it may provide clues to further elucidate its pathogenesis. Topics: Acne Vulgaris; Adult; Antibodies, Anticardiolipin; Antibodies, Antineutrophil Cytoplasmic; Arthritis, Infectious; Colitis; Hidradenitis Suppurativa; Humans; Male; Peroxidase; Pyoderma Gangrenosum; Syndrome | 2021 |
A Glucuronic Acid-Palmitoylethanolamide Conjugate (GLUPEA) Is an Innovative Drug Delivery System and a Potential Bioregulator.
Palmitoylethanolamide (PEA) is an endogenous anti-inflammatory lipid mediator and a widely used nutraceutical. In this study, we designed, realized, and tested a drug-carrier conjugate between PEA (the active drug) and glucuronic acid (the carrier). The conjugate, named GLUPEA, was characterized for its capability of increasing PEA levels and exerting anti-inflammatory activity both in vitro and in vivo. GLUPEA treatment, compared to the same concentration of PEA, resulted in higher cellular amounts of PEA and the endocannabinoid 2-arachidonoyl glycerol (2-AG), and increased 2-AG-induced transient receptor potential vanilloid type 1 (TRPV1) channel desensitization to capsaicin. GLUPEA inhibited pro-inflammatory monocyte chemoattractant protein 2 (MCP-2) release from stimulated keratinocytes, and it was almost as efficacious as ultra-micronized PEA at reducing colitis in dinitrobenzene sulfonic acid (DNBS)-injected mice when using the same dose. GLUPEA is a novel pro-drug able to efficiently mimic the anti-inflammatory and endocannabinoid enhancing actions of PEA. Topics: Amides; Animals; Arachidonic Acids; Calcium; Chemokine CCL8; Colitis; Colon; Dinitrofluorobenzene; Drug Delivery Systems; Endocannabinoids; Ethanolamines; Glucuronic Acid; Glycerides; HaCaT Cells; HEK293 Cells; Humans; Ion Channel Gating; Keratinocytes; Male; Mice, Inbred ICR; Models, Biological; Palmitic Acids; Peroxidase; Poly I-C; TRPV Cation Channels | 2021 |
Lansoprazole a Proton Pump Inhibitor Prevents IBD by Reduction of Oxidative Stress and NO Levels in the Rat.
The inflammatory disease's increased prevalence leads to a major concern around the world. Still, there is a lack of effective and successful therapy in the reversal of Inflammatory Bowel Disease (IBD) symptoms. Whereas, reactive oxygen species (ROS) production and muddled defense capacity of antioxidants in IBD subjects reported several times. Many proton pump inhibitors have been reported previously for their anti-inflammatory effect. The present study is aimed to assess the ameliorative effect of lansoprazole in experimentally induced IBD in rats. Thirty-six female Sprague Dawley rats were divided equally into six groups based on their body weight. Lansoprazole (1, 5, and 10 mg/kg, p.o.) and 5-aminosalicylate (5-ASA, 100 mg/kg, p.o.) served as standard control respectively, given for 18 days once a day. On the 11th day of the study, colitis was induced by intrarectal instillation of 2, 4-Dinitrobenzene sulfonic acid (DNBS), and treatment was continued for the next 7 days. Administration of lansoprazole (at 5 and 10 mg/kg) significantly reduced DAI (Disease Activation Index) and CMDI (Colon Macroscopic Damage Index); which further justifies a reduction in colon inflammation grades, as well as histopathological changes, and reflected by the stalling of body weight. The anti-inflammatory effects were indicated by lowered MPO (myeloperoxidase) and SOD (superoxide dismutase) in colon tissue as well as restores colonic NO (nitric oxide) level. The study shows lansoprazole improved DAI and CMDI scores, reduction of neutrophil infiltration, and an improved antioxidant status indicating an anti-ulcerative effect in DNBS-induced experimental colitis that is comparable with 5-ASA treatment.. The inflammatory disease’s increased prevalence leads to a major concern around the world. Still, there is a lack of effective and successful therapy in the reversal of Inflammatory Bowel Disease (IBD) symptoms. Whereas, reactive oxygen species (ROS) production and muddled defense capacity of antioxidants in IBD subjects reported several times. Many proton pump inhibitors have been reported previously for their anti-inflammatory effect. The present study is aimed to assess the ameliorative effect of lansoprazole in experimentally induced IBD in rats. Thirty-six female Sprague Dawley rats were divided equally into six groups based on their body weight. Lansoprazole (1, 5, and 10 mg/kg, p.o.) and 5-aminosalicylate (5-ASA, 100 mg/kg, p.o.) served as standard control respectively, given for 18 days once a day. On the 11th day of the study, colitis was induced by intrarectal instillation of 2, 4-Dinitrobenzene sulfonic acid (DNBS), and treatment was continued for the next 7 days. Administration of lansoprazole (at 5 and 10 mg/kg) significantly reduced DAI (Disease Activation Index) and CMDI (Colon Macroscopic Damage Index); which further justifies a reduction in colon inflammation grades, as well as histopathological changes, and reflected by the stalling of body weight. The anti-inflammatory effects were indicated by lowered MPO (myeloperoxidase) and SOD (superoxide dismutase) in colon tissue as well as restores colonic NO (nitric oxide) level. The study shows lansoprazole improved DAI and CMDI scores, reduction of neutrophil infiltration, and an improved antioxidant status indicating an anti-ulcerative effect in DNBS-induced experimental colitis that is comparable with 5-ASA treatment. Topics: Animals; Colitis; Colon; Female; Inflammatory Bowel Diseases; Lansoprazole; Nitric Oxide; Oxidative Stress; Peroxidase; Proton Pump Inhibitors; Rats; Rats, Sprague-Dawley | 2021 |
Microbial-derived indoles inhibit neutrophil myeloperoxidase to diminish bystander tissue damage.
During episodes of acute inflammation, polymorphonuclear leukocytes (PMNs) are actively recruited to sites of inflammation or injury where they provide anti-microbial and wound-healing functions. One enzyme crucial for fulfilling these functions is myeloperoxidase (MPO), which generates hypochlorous acid from Cl Topics: Adenocarcinoma; Animals; Bystander Effect; Colitis; Colorectal Neoplasms; Halogenation; Humans; Indoles; Mice; Mice, Inbred C57BL; Microbiota; Neutrophils; Peroxidase; Tumor Cells, Cultured; Tyrosine | 2021 |
An investigation of the anti-inflammatory effects of gabapentin on acetic acid-induced colitis in rats.
Inflammatory bowel disease (IBD) is considered a chronic inflammatory gastrointestinal disease with treatment options which exhibit low efficacies and lead to considerable side effects. Hence, the challenge to alleviate IBD complications is remained to be resolved. The purpose of this study is evaluating anti-inflammatory impacts of gabapentin on acetic acid-induced colitis in rats. Colitis was induced by the instillation of 2 mL of 3% acetic acid solution into rat's colons. Rats were randomly allocated into six groups including normal group, colitis control group, gabapentin-treated groups (25, 50, and 100 mg/kg; i.p.), and dexamethasone-treated group (1 mg/kg; i.p.). Based on the macroscopic assessment besides histological and biochemical findings [myeloperoxidase (MPO), pro-inflammatory cytokines], the efficacy of gabapentin was investigated. Gabapentin (50 and 100 mg/kg), and dexamethasone considerably reduced macroscopic and microscopic colonic lesions induced by acetic acid in rats in comparison with colitis control group. These results were confirmed by reduced levels of MPO activity and colonic concentrations of interleukin-6, interleukin-1 beta, and tumor necrosis factor-alpha, in inflamed colon tissue. Our data demonstrated that gabapentin exerts profitable impacts in experimental colitis that might be ascribed to its anti-inflammatory features and thus can be a potential therapeutic agent for IBD treatment. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Colitis; Colon; Cytokines; Gabapentin; Gene Expression Regulation; Interleukin-1beta; Interleukin-6; Male; Peroxidase; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha | 2021 |
IL-6 downregulates hepatic carboxylesterases via NF-κB activation in dextran sulfate sodium-induced colitis.
Ulcerative colitis (UC) is associated with increased levels of inflammatory factors, which is attributed to the abnormal expression and activity of enzymes and transporters in the liver, affecting drug disposition in vivo. This study aimed to examine the impact of intestinal inflammation on the expression of hepatic carboxylesterases (CESs) in a mouse model of dextran sulfate sodium (DSS)-induced colitis. Two major CESs isoforms, CES1 and CES2, were down-regulated, accompanied by decreases in hepatic microsomal metabolism of clopidogrel and irinotecan. Meanwhile, IL-6 levels significantly increased compared with other inflammatory factors in the livers of UC mice. In contrast, using IL-6 antibody simultaneously reversed the down-regulation of CES1, CES2, pregnane X receptor (PXR), and constitutive androstane receptor (CAR), as well as the nuclear translocation of NF-κB in the liver. We further confirmed that treatment with NF-κB inhibitor abolished IL-6-induced down-regulation of CES1, CES2, PXR, and CAR in vitro. Thus, it was concluded that IL-6 represses hepatic CESs via the NF-κB pathway in DSS-induced colitis. These findings indicate that caution should be exercised concerning the proper and safe use of therapeutic drugs in patients with UC. Topics: Alanine Transaminase; Animals; Antibodies; Aspartate Aminotransferases; C-Reactive Protein; Carboxylesterase; Carboxylic Ester Hydrolases; Cell Line; Clopidogrel; Colitis; Colon; Cytokines; Dextran Sulfate; Humans; Irinotecan; Liver; Male; Mice, Inbred C57BL; Microsomes, Liver; NF-kappa B; Peroxidase; Platelet Aggregation Inhibitors; Topoisomerase I Inhibitors | 2021 |
Composition analysis and oral administered effects on dextran sulfate sodium-induced colitis of galactooligosaccharides bioconverted by Bacillus circulans.
Galactooligosaccharides have been known to have many health benefits as prebiotic ingredients. In this study, we examined the anti-inflammatory activity of the galactooligosaccharide, NeoGOS-P70 (Korean commercial product), in a dextran sodium sulfate-induced colitis model. Next, we performed compositional characterization of NeoGOS-P70, which confirmed that it was a 77.4% high-purity GOS products, including a large amount of 4'-galactosyllactose. Further experiments in DSS-induced colitis model showed that oral administration of NeoGOS-P70 could significantly improve DSS-induced colitis symptoms, such as weight loss, reduction in colon shortening, and suppression of inflammatory mediators, including interleukin-6, tumor necrosis factor-α, and myeloperoxidase secretion from colon of ulcerative colitis mice. Histological analysis of mucin expression in colon tissue revealed the protective effects of NeoGOS-P70. These results suggest the potential of the novel GOS, NeoGOS-P70, as an anti-ulcerative colitis agent that could regulate inflammatory responses. Topics: Animals; Anti-Inflammatory Agents; Bacillus; Colitis; Colitis, Ulcerative; Colon; Dextran Sulfate; Inflammation Mediators; Interleukin-6; Male; Mice; Mice, Inbred BALB C; Peroxidase; Prebiotics; Trisaccharides; Tumor Necrosis Factor-alpha | 2021 |
Effect of cinnamon essential oil on gut microbiota in the mouse model of dextran sodium sulfate-induced colitis.
Increasing evidence has confirmed that the antimicrobial and anti-inflammatory effects of cinnamon essential oil (CEO) contribute to protection against inflammatory bowel disease (IBD). The dextran sodium sulfate (DSS)-induced colitis mouse model was established to investigate the correlation between the protective effects of CEO and the regulation of intestinal microflora. The symptoms of IBD were assessed by measuring the hemoglobin content, myeloperoxidase activity, histopathological observation, cytokines, and toll-like receptor (TLR4) expression. The alteration of the fecal microbiome composition was analyzed by 16S rRNA gene sequencing. The results indicated that the oral administration of CEO enriched with cinnamaldehyde effectively alleviated the development of DSS-induced colitis. In contrast to the inability of antibiotics to regulate flora imbalance, the mice fed with CEO had an improved diversity and richness of intestinal microbiota, and a modified community composition with a decrease in Helicobacter and Bacteroides and an increase in Bacteroidales_S24-7 family and short-chain fatty acids (SCFA)-producing bacteria (Alloprevotella and Lachnospiraceae_NK4A136_group). Moreover, the correlation analysis showed that TLR4 and tumor necrosis factor-α was positively correlated with Helicobacter, but inversely correlated with SCFA-producing bacteria. These findings indicated from a new perspective that the inhibitory effect of CEO on IBD was closely related to improving the intestinal flora imbalance. Topics: Animals; Bacteria; Bacteroides; Cinnamomum zeylanicum; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Fatty Acids, Volatile; Feces; Female; Gastrointestinal Microbiome; Helicobacter; Hemoglobins; Inflammatory Bowel Diseases; Mice; Mice, Inbred C57BL; Oils, Volatile; Peroxidase; RNA, Ribosomal, 16S; Sulfates; Toll-Like Receptor 4 | 2020 |
Sacral nerve stimulation prompts vagally-mediated amelioration of rodent colitis.
Neuromodulation based on the vagal anti-inflammatory reflex has emerged as an exciting therapeutic approach for chronic inflammatory diseases. However, it is unclear whether direct stimulation of the vagus or of pelvic nerves coming from sacral roots, providing the bulk of colonic parasympathetic innervation, is the best approach. We hypothesized that sacral nerve stimulation (SNS) would be an effective treatment for colitis. Age and sex-matched Sprague-Dawley rats were administered 5% dextran sulphate sodium (DSS) in drinking water ad libitum for 7 days. A group of rats was sacrificed after DSS treatment, and the remaining rats were randomized to either sham-SNS or SNS groups, which were performed for 1 hr daily for 10 days. Stimulations were delivered via chronically implanted electrodes using an 8-channel universal pulse generator. Sacral nerve stimulation promoted recovery of colitis demonstrated by decreased disease activity index, myeloperoxidase activity, tissue TNF-alpha, and histological scores as well as an increased colonic M2 macrophage population. Heart rate variability analysis demonstrated a decrease in low frequency and increase in high frequency with SNS, corresponding to increased vagal tone. Additionally, plasma pancreatic peptide was increased and norepinephrine was decreased after SNS in colitis while colon tissue acetylcholine was increased with SNS. This is the first study to the best of our knowledge that demonstrates the benefit of SNS with autonomic mediation. SNS alters the expression of inflammatory cytokines and macrophages as well as modulates neurotransmitters involved in systemic inflammation. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Electric Stimulation Therapy; Heart Rate; Lumbosacral Plexus; Macrophages; Neuroimmunomodulation; Parasympathetic Nervous System; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Spinal Nerves; Tumor Necrosis Factor-alpha | 2020 |
Native κ-carrageenan induced-colitis is related to host intestinal microecology.
Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, has gradually emerged as a public health challenge worldwide. Carrageenan is a popular food additive that has been in use for decades. However, controversy exists regarding to the safety of carrageenan due to its exacerbation of colitis in experimental models. In this study, we studied the effects of vehicle and host intestinal microflora on carrageenan inflammatory properties in C57BL/6 J mice. We found that in high-fat diet model, native carrageenan in drinking water increased the disease activity index (DAI), myeloperoxidase (MPO) activity and the mRNA expression of TLR4 in colon, whereas carrageenan-supplemented diet has no visible effects. However, no signs of colitis were observed under low-fat diet regardless of the mode of vehicle used. Moreover, we discovered that carrageenan-induced colitis in high-fat diet model was robustly correlated with changes in the composition of gut microbiota, specifically Alistipes finegoldii and Bacteroides acidifaciens. Hence, we propose that the inflammatory property of carrageenan is influenced greatly by its intake form via modification of host intestinal microecology. Topics: Animals; Carrageenan; Colitis; Colon; Diet, High-Fat; Disease Models, Animal; Drinking Water; Gastrointestinal Microbiome; Host-Pathogen Interactions; Inflammation; Intestines; Male; Mice, Inbred C57BL; Molecular Weight; Monosaccharides; Peroxidase; Principal Component Analysis; Spectroscopy, Fourier Transform Infrared; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha | 2020 |
Low-dose curcumin reduced TNBS-associated mucin depleted foci in mice by scavenging superoxide anion and lipid peroxides, rebalancing matrix NO synthase and aconitase activities, and recoupling mitochondria.
The role of mitochondrial dysfunction in the pathogenesis of inflammatory bowel diseases (IBD) is still being investigated. This study evaluated the therapeutic effect of curcumin (Cur), a polyphenolic electrophile in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced chronic colitis and mitochondrial dysfunction, in mice.. Colitis was induced by rectal instillation to mice of 30 mg kg. In vitro, a short-term Cur treatment controlled the dose and time dependent mitochondrial toxicity induced by TNBS, by collapsing the generation of superoxide anion and hydroperoxy lipids, rebalancing nitric oxide synthase and aconitase activities, and recoupling mitochondria. In vivo, a daily low-dose Cur abolished mice mortality which reached 27% in model group. Cur improved in a time dependent manner mucosal redox homeostasis, cell apoptosis, mucin depleted crypts and crypt abscesses by controlling prooxidant activity of myeloperoxidase and NO synthase associated to phagocytes influx, quenching hydroperoxy lipids, and reboosting GSH levels.. Cur, by quenching intra and extra mitochondrial ROS generation, rebalancing aconitase/fumarase and MDA/GSH ratios, and recoupling mitochondria, may support mithormesis priming and remitting in IBD. Topics: Aconitate Hydratase; Animals; Apoptosis; Colitis; Colon; Curcumin; Inflammatory Bowel Diseases; Intestinal Mucosa; Lipid Peroxides; Male; Mice; Mitochondria; Mucins; Nitric Oxide Synthase; Oxidation-Reduction; Peroxidase; Reactive Oxygen Species; Superoxides; Trinitrobenzenesulfonic Acid | 2020 |
In-Depth Study of Transmembrane Mucins in Association with Intestinal Barrier Dysfunction During the Course of T Cell Transfer and DSS-Induced Colitis.
There is evidence for a disturbed intestinal barrier function in inflammatory bowel diseases [IBD] but the underlying mechanisms are unclear. Because mucins represent the major components of the mucus barrier and disturbed mucin expression is reported in the colon of IBD patients, we studied the association between mucin expression, inflammation and intestinal permeability in experimental colitis.. We quantified 4-kDa FITC-dextran intestinal permeability and the expression of cytokines, mucins, junctional and polarity proteins at dedicated time points in the adoptive T cell transfer and dextran sodium sulfate [DSS]-induced colitis models. Mucin expression was also validated in biopsies from IBD patients.. In both animal models, the course of colitis was associated with increased interleukin-1β [IL-1β] and tumour necrosis factor-α [TNF-α] expression and increased Muc1 and Muc13 expression. In the T cell transfer model, a gradually increasing Muc1 expression coincided with gradually increasing 4-kDa FITC-dextran intestinal permeability and correlated with enhanced IL-1β expression. In the DSS model, Muc13 expression coincided with rapidly increased 4-kDa FITC-dextran intestinal permeability and correlated with TNF-α and Muc1 overexpression. Moreover, a significant association was observed between Muc1, Cldn1, Ocln, Par3 and aPKCζ expression in the T cell transfer model and between Muc13, Cldn1, Jam2, Tjp2, aPkcζ, Crb3 and Scrib expression in the DSS model. Additionally, MUC1 and MUC13 expression was upregulated in inflamed mucosa of IBD patients.. Aberrantly expressed MUC1 and MUC13 might be involved in intestinal barrier dysfunction upon inflammation by affecting junctional and cell polarity proteins, indicating their potential as therapeutic targets in IBD. Topics: Actins; Animals; CD4-Positive T-Lymphocytes; Cell Adhesion Molecules; Colitis; Colitis, Ulcerative; Crohn Disease; Cytokines; Dextran Sulfate; Dextrans; Disease Models, Animal; Female; Fluorescein-5-isothiocyanate; Humans; Interleukin-10; Interleukin-1beta; Interleukin-6; Intestinal Mucosa; Male; Mice, Inbred BALB C; Mice, SCID; Mucins; Myosin-Light-Chain Kinase; Permeability; Peroxidase; Tight Junction Proteins; Tumor Necrosis Factor-alpha | 2020 |
Gabapentin attenuates intestinal inflammation: Role of PPAR-gamma receptor.
Gabapentin is an anticonvulsant drug that is also used for post-herpetic neuralgia and neuropathic pain. Recently, gabapentin showed anti-inflammatory effect. Nuclear factor kappa B (NFκB) is a regulator of the inflammatory process, and Peroxisome Proliferator-activated Receptor gamma (PPAR-gamma) is an important receptor involved in NFκB regulation. The aim of the present work was to study the potential role of PPAR-gamma receptor in gabapentin-mediated anti-inflammatory effects in a colitis experimental model. We induced colitis in rats using trinitrobenzenosulfonic acid and treated them with gabapentin and bisphenol A dicyldidyl ether (PPAR-gamma inhibitor). Macroscopic lesion scores, wet weight, histopathological analysis, mast cell count, myeloperoxidase, malondialdehyde acid, glutathione, nitrate/nitrite, and interleukin levels in the intestinal mucosa were determined. In addition, western blots were performed to determine the expression of Cyclooxygenase-2 (COX-2) and NFκB; Nitric Oxide Inducible Synthase (iNOS) and Interleukin 1 beta (IL-1β) levels were also determined. Gabapentin was able to decrease all inflammatory parameters macroscopic and microscopic in addition to reducing markers of oxidative stress and cytokines such as IL-1β and Tumor Necrosis Factor alpha (TNF-α) as well as enzymes inducible nitric oxide synthase and cyclooxygenase 2 and inflammatory genic regulator (NFκB). These effect attributed to gabapentin was observed to be lost in the presence of the specific inhibitor of PPAR-gamma. Gabapentin inhibits bowel inflammation by regulating mast cell signaling. Furthermore, it activates the PPAR-gamma receptor, which in turn inhibits the activation of NFκB, and consequently results in reduced activation of inflammatory genes involved in inflammatory bowel diseases. Topics: Animals; Benzhydryl Compounds; Colitis; Cytokines; Gabapentin; Glutathione; Intestinal Mucosa; Male; Malondialdehyde; Mast Cells; NF-kappa B; Peroxidase; Phenols; PPAR gamma; Rats; Rats, Wistar; Signal Transduction; Trinitrobenzenesulfonic Acid | 2020 |
Polysaccharide from flammuliana velutipes improves colitis via regulation of colonic microbial dysbiosis and inflammatory responses.
The aim of this study is to investigate whether Flammuliana Velutipes Polysaccharide (FVP) could aid in the prevention of colitis. Effect of FVP on colitis was evaluated using dextran sulfate sodium (DSS)-induced colitis in rats. Influence of FVP on the expression of inflammation related biomarkers and signal pathway element of TLR4\\NF-κB were assessed. The composition and taxonomy of colonic microbiota were analyzed by 16S rDNA high throughput sequencing, and the concentrations of caecal short fatty chain acids were assessed by chromatography-mass spectrometry. Our results showed that FVP treatment could regulate the colonic microbial dysbiosis and promote the levels of caecal short fatty chain acids, leading to down-regulation of TLR4\\NF-κB signal pathway, which finally ameliorate the colitis. Thus, the present study is the first attempt to elucidate the effect of FVP on colitis and support the potential application of FVP as a functional food ingredient or preventive drugs for colitis. Topics: Amine Oxidase (Copper-Containing); Animals; Cecum; Colitis; Colon; Dextran Sulfate; Dysbiosis; Fatty Acids; Flammulina; Gastrointestinal Microbiome; Inflammation; Intestinal Mucosa; Male; NF-kappa B; Nitric Oxide; Peroxidase; Polysaccharides; Principal Component Analysis; Rats, Sprague-Dawley; Signal Transduction; Superoxide Dismutase; Toll-Like Receptors | 2020 |
Treatment with
This study evaluated the effects of Topics: Animals; Bifidobacterium longum; Colitis; Colon; Cytokines; Disease Models, Animal; Eosinophil Peroxidase; Female; Immunoglobulin A, Secretory; Inflammation; Inflammatory Bowel Diseases; Interleukin-1beta; Intestinal Mucosa; Intestines; Mice; Mice, Inbred BALB C; Peroxidase; Probiotics | 2020 |
The Proteolytic Fraction From Vasconcellea cundinamarcensis Latex Displays Anti-Inflammatory Effect in A Mouse Model of Acute TNBS-Induced Colitis.
The proteolytic fraction (P1G10) from Vasconcellea cundinamarcensis, displays gastric protective and healing activities in different skin lesions in mice and human. In an excisional model, this fraction accelerates resolution of lesions and modulates inflammatory mediators. Based on these data, we assessed its anti-inflammatory activity in murine colitis model, induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) adopted by its physiopathological similarity with human colitis. Twenty four hours after colitis induction followed by three days of treatment, P1G10 at 0.3 and 3.0 mg/Kg induced 30% increase in body weight (p < 0.0001) and ~80% reduction in colon macroscopic damage score (p < 0.05) compared to the untreated TNBS-induced colitis group. Histological analyses showed that 0.3 mg/Kg P1G10 reduced the inflammatory profile and tissue damage (47%, p < 0.05) when it was proteolytically active. Compared to TNBS group, 0.3 mg/Kg P1G10 reduced MPO activity (80%, p < 0.01), MCP-1 (47%, p < 0.05) and TNF-α (50%, no significant) and increased IL-10 (330%, p < 0.001) levels in the supernatant of colonic tissue homogenate. P1G10 treatment also reduced COX-2 expression (60%, p < 0.05) and metalloprotease-2 activity (39%, p < 0.05) while increased globet cell density (140%, p < 0.01), that contributes to mucus layer protection in colonic tissue. Taken together, these findings suggest that low doses of active P1G10 promotes lesion resolution, at least in part by its anti-inflammatory activity, in TNBS-colitis model. Topics: Animals; Anti-Inflammatory Agents; Caricaceae; Colitis; Colon; Cyclooxygenase 2; Cytokines; Disease Models, Animal; Hexosaminidases; Humans; Inflammation Mediators; Latex; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mice; Peroxidase; Proteolysis; Trinitrobenzenesulfonic Acid; Weight Loss | 2020 |
Ping weisan alleviates chronic colitis in mice by regulating intestinal microbiota composition.
Ping weisan (PWS), a complex formulation used in traditional Chinese medicine, is first described in 1107 AD and published in the Prescriptions of Taiping Benevolent Dispensary. We have previously confirmed that PWS has the effect of alleviating DSS-induced chronic ulcerative colitis (UC) in mice.. We aimed to examine whether PWS protects mice from chronic UC by regulating intestinal microbiota composition.. Chronic colitis was induced in C57BL/6 mice with 2.5% DSS in drinking water. PWS (8 g/kg) was orally administered throughout the experiment. Body weight changes, stool consistency and myeloperoxidase (MPO) activity were measured in these mice. Interleukin-17A (IL-17A) and interferon gamma (IFN-γ) mRNA levels were detected by qRT-PCR. The alterations of fecal microflora were investigated by 16S rRNA sequencing. Furthermore, intestinal tight junction protein including occludin, and serum lipopolysaccharide (LPS) level were also detected.. PWS relieved DSS-induced loss of body weight, and improved stool consistency and MPO activity in mice. The levels of IL-17A and IFN-γ mRNA were also reduced after treatment with PWS. PWS not only regulated occludin level but also decreased serum LPS. We further showed DSS-induced changes in intestinal microbial composition and richness are significantly regulated by PWS. PWS treatment significantly decreased the abundance of Bacteroidetes, but increased the abundance of Firmicutes in chronic UC mice induced by DSS.. Combining with our previous results, we found that PWS could exert anti-UC role by rebalancing intestinal bacteria. Topics: Animals; Chronic Disease; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Drugs, Chinese Herbal; Dysbiosis; Gastrointestinal Agents; Gastrointestinal Microbiome; Interferon-gamma; Interleukin-17; Lipopolysaccharides; Male; Mice, Inbred C57BL; Occludin; Peroxidase; Weight Loss | 2020 |
The Antioxidant and Anti-Inflammatory Properties of
Induction of colitis was performed by intrarectally injection of dinitrobenzene sulfonic acid (DNBS). Cashew nuts were administered daily orally (100 mg/kg) in DNBS-injected mice.. Four days after DNBS, histological and macroscopic colon alterations as well as marked clinical signs and increased cytokine production were observed. Neutrophil infiltration, measured by myeloperoxidase (MPO) positive immunostaining, was correlated with up-regulation of adhesion molecules ICAM-1 and P-selectin in colons. Oxidative stress was detected with increased malondialdehyde (MDA) levels, nitrotyrosine, and poly ADP-ribose polymerase (PARP) positive staining in inflamed colons. Oral treatment with cashew nuts reduced histological, macroscopic damage, neutrophil infiltration, pro-inflammatory cytokines and MDA levels, as well as nitrotyrosine, PARP and ICAM-1, and P-selectin expressions. Colon inflammation could be related to nuclear factor (NF)-kB pathway activation and reduced manganese superoxide dismutase (MnSOD) antioxidant activity. Cashew nuts administration inhibited NF-kB and increased MnSOD antioxidant expressions.. The results suggested that oral assumption of cashew nuts may be beneficial for the management of colitis. Topics: Anacardium; Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Colitis; Cytokines; Disease Models, Animal; Intestinal Mucosa; Lipid Metabolism; Male; Malondialdehyde; Mice; Neutrophils; Nitric Oxide Synthase Type II; Nuts; Oxidative Stress; Peroxidase; Rats | 2020 |
Inhibition of proprotein convertase subtilisin/kexin type 9 attenuates 2,4,6-trinitrobenzenesulfonic acid-induced colitis via repressing toll-like receptor 4/nuclear factor-kappa B.
Inflammatory bowel disease (IBD) is characterized by recurring inflammatory disorders in digestive system, and devoid of effective treatment. Proprotein convertase subtilisin/kexin type 9 (PCSK9), stimulated via inflammation whose inhibition could decrease secretion of inflammatory factors. We then determined whether inhibition of PCSK9 could improve the inflammation. First, rats model of colitis was first established via administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS), and then verified via determination of body weight loss, myeloperoxidase (MPO) activity, and histopathological analysis of colonic damage. Results showed that treatment with TNBS induced a great body weight loss, MPO activity increase, and serious colonic damage, showing an obviously character of IBD. PCSK9 was elevated in TNBS-induced rats, and PCSK9 inhibition delivered by adenovirus vector increased the body weight, decreased MPO activity, and ameliorated histological change of colon. Second, the protective effect of PCSK9 inhibition against TNBS-induced colitis was accompanied by decrease of proinflammatory factors secretion, including tumor necrosis factor-α, interleukin-1β, interleukin-6, intercellular adhesion molecule 1, and monocyte chemoattractant protein-1. TNBS could activate toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway, while PCSK9 inhibition suppressed activation of TLR4/NF-κB in TNBS-induced rats. In conclusion, PCSK9 inhibition attenuated TNBS-induced rat colitis through anti-inflammatory effect under inactivation of TLR4/NF-κB, suggesting potential therapeutic strategy in IBD. Topics: Adenoviridae; Animals; Body Weight; Chemokine CCL2; Colitis; Colon; Gene Expression Regulation; Genetic Vectors; Inflammation; Intercellular Adhesion Molecule-1; Interleukin-1beta; Interleukin-6; Male; NF-kappa B; PCSK9 Inhibitors; Peroxidase; Proprotein Convertase 9; Rats; Rats, Wistar; RNA, Small Interfering; Signal Transduction; Toll-Like Receptor 4; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2020 |
Lessons on the Sigma-1 Receptor in TNBS-Induced Rat Colitis: Modulation of the UCHL-1, IL-6 Pathway.
Inflammatory Bowel Disease (IBD) is an autoimmune ailment of the gastrointestinal (GI) tract, which is characterized by enhanced activation of proinflammatory cytokines. It is suggested that the sigma-1 receptor (σ1R) confers anti-inflammatory effects. As the exact pathogenesis of IBD is still unknown and treatment options are limited, we aimed to investigate the effects of σ1R in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced experimental colitis. To this end, male Wistar-Harlan rats were used to model colitic inflammation through the administration of TNBS. To investigate the effects of σ1R, Fluvoxamine (FLV, σ1R agonist) and BD1063 (σ1R antagonist) were applied via intracolonic administration to the animals once a day for three days. Our radioligand binding studies indicated the existence of σ1Rs as [ Topics: Animals; Colitis; Cytokines; Disease Models, Animal; Disease Susceptibility; Fluvoxamine; Gene Expression Regulation; Heme Oxygenase (Decyclizing); Inflammation Mediators; Interleukin-6; Ligands; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Protein Binding; Rats; Receptors, sigma; Severity of Illness Index; Sigma-1 Receptor; Signal Transduction; Trinitrobenzenesulfonic Acid; Ubiquitin Thiolesterase | 2020 |
Silver nanoparticles based on blackcurrant extract show potent anti-inflammatory effect in vitro and in DSS-induced colitis in mice.
Silver nanoparticles have been used in a range of applications and although they are already employed in medicine, there are new, promising possibilities for their utilization. We investigated the potential of silver nanoparticles obtained with the use of blackcurrant extract in vitro in the LPS-stimulated RAW264.7 macrophages and in vivo in the murine DSS-induced colitis model. The examined formulations contained particles of 95 nm (Ag95) and 213 nm (Ag213) diameter. In vitro, both formulations inhibited nitric oxide (NO) release. In vivo, the preparations alleviated colitis as evidenced by a decreased macroscopic score and myeloperoxidase activity (indicative of neutrophil infiltration). In both cases, the nanoparticles of larger diameter showed better anti-inflammatory properties. Although further tests are required, our results indicate a plausible new use of silver nanoparticles in inflammatory bowel diseases. Topics: Animals; Cell Survival; Colitis; Disease Models, Animal; Lipopolysaccharides; Male; Metal Nanoparticles; Mice; Mice, Inbred BALB C; Particle Size; Peroxidase; Plant Extracts; RAW 264.7 Cells; Ribes; Silver; Technology, Pharmaceutical | 2020 |
Inhibitory Effects of Peroxidase from Foxtail Millet Bran on Colitis-Associated Colorectal Carcinogenesis by the Blockage of Glycerophospholipid Metabolism.
Abnormal glycerophospholipid (GPL) metabolism represented by phosphatidylcholine (PC) and phosphatidylethanolamine (PE) has been as a universal metabolic hallmark of cancer, which is involved in tumor progression. Our previous finding showed that peroxidase from foxtail millet bran (FMBP) exhibited significant anticolorectal cancer (CRC) activity in vitro and in nude mice. Presently, the potential of FMBP in clinical application was further evaluated by an azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colitis-associated carcinogenesis (CAC) mice model, revealed the pivotal role of GPL metabolism in anti-CRC effects of FMBP. Excitedly, FMBP significantly reduced the number and volume of CAC polyps of mice and effectively improved physiological indexes of CAC mice. Meanwhile, the elevated expressions of CRC early markers (cyclooxygenase 2, tumor-proliferating nuclear antigen Ki-67, and EGF module-containing mucin-like receptor 1) in CAC mice were efficiently prevented by FMBP treatment. Metabolomics analysis showed that the elevated abundances of PC and PE involved in GPL metabolism in CAC mice were markedly decreased in FMBP-treated groups, which was also verified in human CRC cells. Further, FMBP reduced the expression levels of PE and PC key metabolic enzymes, resulting in the blockage of GPL metabolism and insufficient adenosine triphosphate to maintain CRC growth. Collectively, FMBP has the potential as a preventive and therapeutic candidate for CRC through the blockage of GPL metabolism. Topics: Animals; Benzofurans; Carcinogenesis; Cell Line, Tumor; Colitis; Colorectal Neoplasms; Dextran Sulfate; Disease Models, Animal; Glycerophospholipids; Humans; Male; Mice; Mice, Nude; Peroxidase; Plant Proteins; Quinolines; Setaria Plant | 2020 |
Mucoadhesive nanoparticles-based oral drug delivery systems enhance ameliorative effects of low molecular weight heparin on experimental colitis.
Low molecular weight heparin (LMWH) is reported to have therapeutic action on ulcerative colitis (UC). To facilitate its oral administration and improve the colon-targeting property, LMWH-loaded nanoparticles (TMC-NPs and SA-TMC-NPs) are prepared and evaluated by a series of studies, including their stabilities, drug release profiles, mucosal permeation, mucoadhesion, cytotoxicities, cellular uptake profiles, anticoagulant and anti-inflammatory activities, mucosal healing properties, biosafety and ameliorative effects on experimental colitis. Consequently, oral administration of LMWH-loaded NPs for 5 days perform significant therapeutic effects on mice, which are manifested as improved body weight gains, colon length, DAI score, MPO activity and histological characteristics. Besides, SA-TMC-NPs show better colon-targeting property than TMC-NPs that is demonstrated by lower oral absorption (ATPP 38.95 s) and stronger mucoadhesion (kcps reduces 36.46 %) to inflamed colon tissues. Therefore, TMC-based NPs are proved to be as promising oral colon-targeting drug delivery systems of LMWH and has potential application in UC treatment. Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Biomarkers; Chitosan; Colitis; Colon; Drug Delivery Systems; Drug Liberation; Gene Expression; Heparin, Low-Molecular-Weight; Kinetics; Male; Mice; Nanoparticles; Peroxidase; Rats; Rats, Sprague-Dawley; RAW 264.7 Cells; Treatment Outcome; Trinitrobenzenesulfonic Acid | 2020 |
A novel danshensu derivative ameliorates experimental colitis by modulating NADPH oxidase 4-dependent NLRP3 inflammasome activation.
We have previously reported a novel compound [4-(2-acetoxy-3-((R)-3-(benzylthio)-1-methoxy-1-oxopropan-2-ylamino)-3-oxopropyl)-1,2-phenylene diacetate (DSC)], derived from danshensu, exhibits cytoprotective activities in vitro. Here, we investigated the effects and underlying mechanisms of DSC on dextran sodium sulphate (DSS)-induced experimental colitis. We found that DSC treatment afforded significant protection against the development of colitis, evidencing by suppressed inflammatory responses and enhanced barrier integrity. Intriguingly, DSC specifically down-regulated DSS-induced colonic NADPH oxidase 4 (Nox4) expression, accompanied by a balanced redox status, suppressed nuclear factor-κB (NF-κB) and NLRP3 inflammasome activation and up-regulated nuclear factor (erythroid-derived 2)-like 2 and haeme oxygenase-1 expression. In vitro study also demonstrated DSC also markedly decreased Nox4 expression and activity associated with inhibiting reactive oxygen species generation, NF-κB activation and NLRP3 inflammasome activation in bone marrow-derived macrophages. Either lentiviral Nox4 shRNA-mediated Nox4 knockdown or Nox4-specific small-interfering RNA mimicked effects of DSC by suppressing NLPR3 inflammasome activation to alleviate experimental colitis or inflammatory macrophage response. Collectively, our results provide the first evidence that DSC ameliorates experimental colitis partly through modulating Nox4-mediated NLRP3 inflammasome activation. Topics: Animals; Colitis; Cytokines; Hydrogen Peroxide; Inflammasomes; Lactates; Male; Mice; Mice, Inbred C57BL; NADPH Oxidase 4; NADPH Oxidases; NF-kappa B p50 Subunit; NLR Family, Pyrin Domain-Containing 3 Protein; Peroxidase; Reactive Oxygen Species | 2020 |
Therapies aimed at modulating cytokines have been used to treat inflammatory illnesses, such as inflammatory bowel disease. On the other hand, patients may become intolerant, refractory, or present with several side effects.. All mice (C57BL/6 male) were evaluated daily for their food and water intake, bodyweight variations, and clinical signs of disease. Colon inflammation was induced by exposure to DSS for 6 consecutive days. SPI was given orally at 50, 100, and 250 mg/kg/day. ELISA was performed to assess the production of cytokines. Myeloperoxidase and nitric oxide were also investigated. The level of microscopic damage was assessed by staining colon sections with hematoxylin and eosin.. SPI attenuated the DSS-induced inflammation, with improvements in the clinical signs and a decrease in the production of inflammatory cytokines, such as tumor necrosis factor-α and interferon-γ. In addition, particularly at 250 mg/kg, SPI attenuated the severity of colitis by modulating the level of mucosal and submucosal cell infiltration, which preserved the epithelial barrier.. SPI may be an alternative source of bioactive molecules with immunomodulatory properties, and has great potential to be used in the treatment of inflammatory diseases. Topics: Animals; Colitis; Dextran Sulfate; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Immunologic Factors; Interferon-gamma; Mice; Mice, Inbred C57BL; Nitric Oxide; Peroxidase; Spirulina; Tumor Necrosis Factor-alpha | 2020 |
Synergistic therapeutic effect of mesenchymal stem cells and tolerogenic dendritic cells in an acute colitis mouse model.
Cell-based therapy with tolerizing cells has been applied for the treatment of inflammatory bowel disease (IBD) in previous experimental and clinical studies with promising results. In the current study, we utilized the dextran sulfate sodium (DSS)-induced colitis model, to investigate if tolerogenic dendritic cell-mesenchymal stem cell (tDC-MSC) combination therapy can augment the therapeutic effects of single transplantation of each cell type. The effect of MSC and tDC co-transplantation on the severity of colitis was assessed by daily monitoring of body weight, stool consistency, and rectal bleeding, and compared with control groups. Moreover, the colon length, colon weight, myeloperoxidase (MPO) activity were measured and evaluated with histological analysis of colon tissues. The Treg cell percentage and cytokine levels in spleens and mesenteric lymph nodes (MLNs) were measured by flow cytometry and ELISA, respectively. The results showed co-transplantation of MSCs and tDCs was more effective in alleviating the clinical and histological manifestations of colitis than monotherapy, especially when compared with MSC alone. The protective effects of tDC-MSC were accompanied by the induction of Treg cells and increased the production of anti-inflammatory cytokines in spleens and mesenteric lymph nodes. Together, co-transplantation of MSCs and tDCs could be a promising and effective therapeutic approach in the treatment of IBD. Topics: Animals; Antigens, CD; Colitis; Dendritic Cells; Female; Mesenchymal Stem Cell Transplantation; Mice; Mice, Inbred C57BL; Peroxidase; T-Lymphocytes, Regulatory; Time Factors | 2020 |
Evaluation of the effect of liposomes loaded with chlorogenic acid in treatment of 2,4,6-trinitrobenzenesulfonic acid-induced murine colitis.
Crohn's Disease (CD), one of the types of inflammatory bowel disease, poses a significant challenge to modern healthcare. This condition severely impacts patients' quality of life, and its incidence is continuously rising. Despite constant research, current treatment options are limited and largely unsuccessful and result in serious side effects, therefore new therapy alternatives are needed. Liposomal formulation provides a new hope for disease management. In our study, we characterized the anti-inflammatory activity of mesalazine (5-ASA) and chlorogenic acid (CGA) encapsulated in liposomal formulation in the animal model of CD. Liposomes were obtained by thin film hydration method and characterized in terms of suspension stability and particle size and distribution. Colitis was induced in mice by intracolonic (i.c.) administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS). The effect of treatment with liposomal suspensions of 5-ASA and CGA was evaluated macroscopically and by measuring myeloperoxidase (MPO) activity. We observed that liposome-encapsulated 5-ASA (5 mg/kg), but not CGA (20 mg/kg) attenuated colitis as evidenced by a decreased macroscopic and microscopic scores. It may be hypothesized that the composition of liposomal lipid bilayer as well as the switch in macrophage populations leading to unfavorable accumulation of anti-inflammatory agents in the cells may underly the efficiency of obtained liposomes and need to be taken into consideration in further studies on drug delivery. Topics: Animals; Anti-Inflammatory Agents; Chlorogenic Acid; Colitis; Colon; Disease Models, Animal; Inflammatory Bowel Diseases; Liposomes; Male; Mesalamine; Mice; Mice, Inbred BALB C; Peroxidase; Quality of Life; Trinitrobenzenesulfonic Acid | 2019 |
Protective effect and mechanism of polysaccharide from Dictyophora indusiata on dextran sodium sulfate-induced colitis in C57BL/6 mice.
Polysaccharide (DIP) from Dictyophora indusiata has showed noteworthy anti-inflammatory activities. Given that the closely relationship between inflammation and ulcerative colitis, we speculated that DIP may alleviate ulcerative colitis. However, there was not any report about the effect of DIP on this disease. The purpose of this paper is to explore the protective effect and mechanism of DIP on DSS-induced colitis in C57BL/6 mice. The data indicated that DIP could improve DSS-induced colitis by restoring intestinal barrier function and regulating macrophage polarization. Its mechanism was found to be associated with decreased oxidative stresses and inflammation, suppressive key signal pathways related with colitis, improved the expression of tight junction proteins and down-regulated M1 macrophage polarization. The results suggested that DIP could be served as an agent for improving intestinal inflammation in functional foods or nutraceutical formulations. Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Basidiomycota; Colitis; Colon; Cytokines; Dextran Sulfate; Macrophages; Male; Mice, Inbred C57BL; Oxidative Stress; Peroxidase; Polysaccharides; Protective Agents; Signal Transduction; Tight Junction Proteins | 2019 |
Cesarean section increases sensitivity to oxazolone-induced colitis in C57BL/6 mice.
Children born by cesarean section (CS) have an increased risk of developing inflammatory bowel disease (IBD), possibly due to skewed microbial colonization during birth and consequently impaired bacterial stimulation of the developing immune system. The aim of this study was to investigate the association between CS and experimental colitis in a murine model of IBD. It was hypothesized that CS aggravates colonic inflammation due to a change in gut microbiota (GM) composition. C57BL/6 mice, delivered by CS or vaginal delivery (VD), were intra-rectally challenged with oxazolone at 8 weeks of age and monitored for colitis symptoms. The results showed that CS delivered mice experienced an increased body weight loss and colon weight, together with higher colonic concentrations of TNF-α and MPO compared with VD mice. Increased infiltration of inflammatory cells was present in CS delivered mice, as well as a downregulation in expression of the gut integrity genes occludin and tight junction protein 1 indicative of an impaired barrier function. The GM from CS delivered mice without colitis partly contributed to the increase in colitis symptoms when inoculated into germ-free recipient mice. In conclusion, CS increased sensitivity to oxazolone induced colitis in mice. Topics: Animals; Cesarean Section; Colitis; Colon; Disease Models, Animal; Fecal Microbiota Transplantation; Female; Gastrointestinal Microbiome; Inflammation Mediators; Intestinal Mucosa; Mice, Inbred C57BL; Oxazolone; Peroxidase; Pregnancy; Severity of Illness Index; Tumor Necrosis Factor-alpha | 2019 |
Anti-inflammatory effects of eriocitrin against the dextran sulfate sodium-induced experimental colitis in murine model.
Inflammatory bowel disease (IBD) is a continual ailment condition which engrosses the entire alimentary canal. The IBD can be primarily distinguished into two forms, ulcerative colitis, and Crohn's disease. The major symptoms of IBD include pustules or abscesses, severe abdominal pain, diarrhea, fistula, and stenosis, which may directly affect the patient's quality of life. A variety of mediators can stimulate the circumstances of IBD, some examples include infections by microbes such as bacteria, perturbation of the immune system and the surrounding environment of the intestines. Severe colitis was stimulated in the experimental animals through administering 4% dextran sulfate sodium (DSS) which is mixed in water ad libitum for 6 days. Eriocitrin (30 mg/kg) was then administered to the experimental animals followed by the induction of severe colitis to evaluate the therapeutic prospective of eriocitrin against the colon inflammation stimulated by DSS. In this study, eriocitrin (30 mg/kg) demonstrated significant (P < .05) attenuation activity against the DSS-stimulated severe colitis in experimental animals. Eriocitrin counteracted all of the clinical deleterious effects induced by DSS, such as body-weight loss, colon shortening, histopathological injury, accretion of infiltrated inflammatory cells at the inflamed region and the secretion of inflammatory cytokines. The results clearly showed that eriocitrin effectively attenuated DSS-induced acute colitis in experimental animals. Topics: Animals; Anti-Inflammatory Agents; Citrus; Colitis; Colon; Cyclooxygenase 2; Cytokines; Dextran Sulfate; Disease Models, Animal; Flavanones; Inflammation; Male; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Plant Extracts; Severity of Illness Index; Weight Loss | 2019 |
Target-Specific Fluorescence-Mediated Tomography for Non-Invasive and Dynamic Assessment of Early Neutrophil Infiltration in Murine Experimental Colitis.
The role of neutrophils in the pathogenesis of inflammatory bowel disease (IBD) is still only incompletely understood. Here, we evaluated target-specific fluorescence-mediated tomography (FMT) for visualization of neutrophil infiltration in murine experimental DSS-induced colitis. Colitis was assessed using clinical, endoscopic, and histopathological parameters. Intestinal neutrophil infiltration was determined at day 0, 4, and 10 by targeted FMT after injection of a neutrophil-specific fluorescence-labelled monoclonal antibody (Gr-1). Complementary, immunofluorescence tissue sections with Gr-1 and ELISA-based assessment of tissue myeloperoxidase (MPO) served as the gold standard for the quantification of neutrophil infiltration. Colitic animals showed decreasing body weight, presence of fecal occult blood, and endoscopic signs of inflammation. FMT revealed a significantly increased level of fluorescence only four days after colitis induction as compared to pre-experimental conditions (pmol tracer 73.2 ± 18.1 versus 738.6 ± 80.7; Topics: Animals; Colitis; Colon; Disease Models, Animal; Female; Fluorescence; Inflammation; Inflammatory Bowel Diseases; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; Neutrophils; Peroxidase; Tomography | 2019 |
Andrographolide Derivative AL-1 Ameliorates Dextran Sodium Sulfate-Induced Murine Colitis by Inhibiting NF-
Trinitrobenzenesulfonic acid (TNBS) and dextran sodium sulfate (DSS) are commonly used to induce experimental murine ulcerative colitis (UC). Our recent study has demonstrated that a novel andrographolide derivative, AL-1, ameliorated TNBS-induced colitis in mice. However, the effect of AL-1 on DSS-induced murine colitis and the underlying mechanisms are yet unknown. In the present study, we aimed to investigate the therapeutic potential of AL-1 against DSS-induced UC in mice and to define its mechanisms of action. Oral administration of AL-1 attenuated body weight loss, reduced colon length shortening, lowered the disease activity index score, and alleviated colon histological damage. AL-1 significantly inhibited myeloperoxidase activity and suppressed immune inflammatory responses in colonic tissues. Moreover, AL-1 reversed DSS-altered expression of inflammatory cytokines in DSS-induced colitis mice. Importantly, the efficacy of 45 mg/kg of AL-1 was higher than that of 100 mg/kg of the positive control drugs 5-aminosalicylic acid and mesalazine. AL-1 decreased lipopolysaccharide-induced generation of reactive oxygen species and nitric oxide in cultured macrophages in vitro; it also reversed the altered expression of inflammatory cytokines. In both in vivo and in vitro studies, Western blot analysis revealed that AL-1 reduced the expression of phosphorylated NF- Topics: Animals; Cell Nucleus; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Diterpenes; Female; Inflammation; Inflammation Mediators; Lipopolysaccharides; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Models, Biological; NF-kappa B; Nitric Oxide; Peroxidase; RAW 264.7 Cells; Reactive Oxygen Species | 2019 |
Indigo Naturalis Suppresses Colonic Oxidative Stress and Th1/Th17 Responses of DSS-Induced Colitis in Mice.
Topics: AMP-Activated Protein Kinase Kinases; Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Drugs, Chinese Herbal; Humans; Immunity, Cellular; Inflammatory Bowel Diseases; Male; Medicine, Chinese Traditional; Mice; Mice, Inbred C57BL; NF-E2-Related Factor 2; Oxidative Stress; Peroxidase; Protein Kinases; Signal Transduction; Th1 Cells; Th17 Cells | 2019 |
Effects of anti-TNF-α in experimental diversion colitis.
To evaluate the effects of infliximab on the inflammation of the colonic mucosa devoid from fecal stream.. Twenty-four rats were submitted to a Hartmann's procedure. They remained for 12 weeks with the fecal derivation to development of diversion colitis on excluded colorectal stump. After this period, they were divided into 3 groups: one group received intervention with saline (2.0 mL / week), other group infliximab at doses of 5 mg/kg/week and the other 10 mg/kg/week for five consecutively weeks. Concluded the intervention period, the animals were euthanized to remove colon segments with and without fecal stream. Colitis was diagnosed by histological analysis and the degree of inflammation by validated score. The neutrophilic infiltrate was evaluated by tissue expression of myeloperoxidase identified by immunohistochemical. The tissue content of myeloperoxidase was measured by computer-assisted image analysis.. The inflammatory score was high in colonic segments without fecal stream. The intervention with infliximab reduced the inflammatory score in excluded colonic segments. The content of myeloperoxidase was reduced in colonic segments of animals treated with infliximab mainly in high concentrations.. Intervention with infliximab reduced the inflammation and the neutrophil infiltrate in colonic segments devoid of the fecal stream. Topics: Animals; Colitis; Colon; Feces; Gastrointestinal Agents; Gastrointestinal Transit; Image Processing, Computer-Assisted; Immunohistochemistry; Infliximab; Intestinal Mucosa; Male; Neutrophil Infiltration; Peroxidase; Rats, Wistar; Reproducibility of Results; Time Factors; Treatment Outcome; Tumor Necrosis Factor-alpha | 2019 |
Sucralose Increased Susceptibility to Colitis in Rats.
Topics: Animals; Colitis; Crohn Disease; Dysbiosis; Ileitis; Peroxidase; Proteobacteria; Rats; Sucrose; Sweetening Agents | 2019 |
Colitis Alters Oxysterol Metabolism and is Affected by 4β-Hydroxycholesterol Administration.
Inflammatory bowel diseases [IBD] represent a challenging health issue with a complex aetiology involving genetic and environmental parameters. Although our understanding of the pathophysiology of IBD has improved, much remains to be explored. In this context, bioactive lipids, more specifically oxysterols, i.e. oxygenated derivatives of cholesterol, represent an interesting avenue to investigate. Indeed, oxysterols or their receptors are involved in inflammation and immune regulation. Therefore, we set out to study the oxysterome in IBD.. We used both high-performance liquid chromatograph/mass spectroscopy and molecular biology tools to quantify oxysterol levels and the expression of their metabolic enzymes in several models of murine colitis [both acute and chronic], as well as in colon biopsies from patients with Crohn's disease and ulcerative colitis.. We found that the oxysterome is altered in IBD, in both acute and chronic murine models as well as in human IBD. Two of the oxysterols quantified, 4β-hydroxycholesterol and 25-hydroxycholesterol, were consistently altered in all our models and therefore could be of interest in this context. Hence, we administered them to mice with colitis. While 25-hydroxycholesterol had no effect, 4β-hydroxycholesterol worsened colon inflammation.. Our study addresses the potential involvement of oxysterols in colitis and clearly points towards an active role as well as a clinical relevance for these bioactive lipids. Topics: Animals; Chromatography, High Pressure Liquid; Colitis; Colitis, Ulcerative; Colon; Crohn Disease; Disease Models, Animal; Humans; Hydroxycholesterols; Liver; Male; Mass Spectrometry; Mice; Mice, Inbred C57BL; Oxysterols; Peroxidase; Real-Time Polymerase Chain Reaction; Transcriptome | 2019 |
Therapeutic switching of sulpiride, an anti-psychotic and prokinetic drug, to an anti-colitic drug using colon-specific drug delivery.
To test whether sulpiride (SP), an anti-psychotic and prokinetic drug, shows beneficial effects on experimental murine colitis, a colon-targeted prodrug of SP, 5-(aminoethanoylsulfamoyl)-N-[(1-ethylpyrrolidin-2-yl)methyl]-2-methoxybenzamide (glycylsulpiride (GSP)), was synthesized and its colonic delivery and therapeutic activity against 2,4-dinitrobenzenesulfonic acid (DNBS)-induced rat colitis were assessed. Synthesis of GSP was verified by infrared and proton nuclear magnetic resonance spectroscopy. GSP was converted to SP when incubated with the cecal contents but not when incubated with the small intestinal contents. The percent conversion was about 50.5% at 6 h and 67.7% at 10 h. Colonic delivery of GSP was examined by comparison with sulfasalazine (SSZ), a colon-specific prodrug of 5-aminosalicylic acid currently used for the treatment of inflammatory bowel disease. The two prodrugs accumulated similar concentrations of the corresponding parent drugs in the cecum at 2, 4, and 6 h after oral gavage. Although oral gavage of GSP released millimolar level of SP in the large intestine, SP was hardly detected in the blood. GSP improved colonic damage score and reduced myeloperoxidase activity up to 80.5% in the inflamed colon in a dose-dependent manner. Moreover, GSP was able to reduce the levels of inflammatory mediators in the inflamed colon. Overall, the anti-colitic effectiveness of GSP and SSZ was similar. In conclusion, colonic delivery of SP ameliorates DNBS-induced colitis in rats with no significant systemic absorption of SP. Thus, colon-targeted SP may be therapeutically switched to an anti-colitic drug. Topics: Animals; Benzamides; Colitis; Colon; Dinitrofluorobenzene; Disease Models, Animal; Dose-Response Relationship, Drug; Down-Regulation; Drug Delivery Systems; Male; Peroxidase; Prodrugs; Rats; Rats, Sprague-Dawley; Sulfasalazine; Sulpiride | 2019 |
Assessing the Safety and Efficacy of Lactobacillus plantarum MTCC 5690 and Lactobacillus fermentum MTCC 5689 in Colitis Mouse Model.
Probiotic lactobacilli have an unprecedented history of safe use, although some cases of infections have raised concerns about their safety, and hence, a rigorous screening of any new strain even of Lactobacillus is a must in order to study possible adverse interactions with the host, particularly under unhealthy conditions. The present study was, therefore, undertaken to investigate the safety as well as therapeutic efficacy of probiotic Lactobacillus plantarum MTCC 5690 and L. fermentum MTCC 5689 strains in dextran sodium sulfate (DSS)-induced colitis mouse model. Both MTCC 5690 and MTCC 5689 did not induce any detrimental effect on the colitic mice, as was reflected by normal colon and caecum length, blood biochemistry, hematology, and absence of inflammation. Although translocation of both the strains was observed in extraintestinal organs, probiotic-fed mice had significantly improved intestinal permeability and decreased myeloperoxidase (MPO) activity. Probiotic interventions also led to an improved health index and better growth of colitis mice compared to colitis animals with no probiotic intervention. These results point towards the safe use of L. plantarum MTCC 5690 and L. fermentum MTCC 5689 as biotherapeutics for amelioration of inflammatory conditions after establishing their efficacy in human clinical trials. Topics: Animals; Colitis; Dextran Sulfate; Disease Models, Animal; Drug Evaluation, Preclinical; Humans; Lactobacillus plantarum; Limosilactobacillus fermentum; Male; Mice; Peroxidase; Probiotics | 2019 |
Administration of the Hyper-immune Bovine Colostrum Extract IMM-124E Ameliorates Experimental Murine Colitis.
Inflammatory bowel disease [IBD] is accompanied by lesions in the epithelial barrier, which allow translocation of bacterial products from the gut lumen to the host's circulation. IMM-124E is a colostrum-based product containing high levels of anti-E.coli-LPS IgG, and might limit exposure to bacterial endotoxins. Here, we investigated whether IMM-124E can ameliorate intestinal inflammation.. Acute colitis was induced in WT C57Bl/6J mice by administration of 2.5% dextran sodium sulphate [DSS] for 7 days. T cell transfer colitis was induced via transfer of 0.5 x 106 naïve T cells into RAG2-/- C57Bl/6J mice. IMM-124E was administered daily by oral gavage, either preventively or therapeutically.. Treatment with IMM-124E significantly ameliorated colitis in acute DSS colitis and in T cell transfer colitis. Maximum anti-inflammatory effects were detected at an IMM-124E concentration of 100 mg/kg body weight, whereas 25 mg/kg and 500 mg/kg were less effective. Histology revealed reduced levels of infiltrating immune cells and less pronounced mucosal damage. Flow cytometry revealed reduced numbers of effector T helper cells in the intestine, whereas levels of regulatory T cells were enhanced. IMM-124E treatment reduced the DSS-induced increase of serum levels of lipopolysaccharide [LPS]-binding protein, indicating reduced systemic LPS exposure.. Our results demonstrate that oral treatment with IMM-124E significantly reduces intestinal inflammation, via decreasing the accumulation of pathogenic T cells and concomitantly increasing the induction of regulatory T cells. Our study confirms the therapeutic efficacy of IMM-124E in acute colitis and suggests that administration of IMM-124E might represent a novel therapeutic strategy to induce or maintain remission in chronic colitis. Topics: Animals; Blotting, Western; Cattle; Colitis; Colon; Colostrum; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Immunoglobulin G; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Peroxidase | 2019 |
Anticolitic Effect of Viscum coloratum through Suppression of Mast Cell Activation.
Topics: Animals; Caco-2 Cells; Colitis; Dextran Sulfate; Humans; Immunoglobulin E; Inflammation Mediators; Interleukin-6; Male; Mast Cells; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mice, Inbred C57BL; Peroxidase; Phytotherapy; Plant Extracts; Tumor Necrosis Factor-alpha; Viscum; Zonula Occludens-1 Protein | 2019 |
Chronic colitis-induced visceral pain is associated with increased anxiety during quiescent phase.
Inflammatory bowel diseases (IBD) are characterized by repetition of flares and remission periods leading to chronic postinflammatory sequelae. Among postinflammatory sequelae, one-third of patients with IBD are suffering from functional symptoms or psychological comorbidities that persist during remission. The aim of our study was to assess functional and behavioral sequelae of chronic colitis in rats with quiescent intestinal inflammation. Chronic colitis was induced by a weekly intrarectal injection of increasing concentrations of trinitrobenzene sulfonic acid (TNBS) for 3 wk (15-45 mg of TNBS) in 30 rats, whereas the control rats ( Topics: Animals; Anxiety; Behavior, Animal; Colitis; Colon; Cytokines; Disease Models, Animal; Gastrointestinal Motility; Inflammation; Inflammatory Bowel Diseases; Male; Permeability; Peroxidase; Rats; Tight Junction Proteins; Visceral Pain | 2019 |
A ropy exopolysaccharide producing strain Bifidobacterium longum subsp. longum YS108R alleviates DSS-induced colitis by maintenance of the mucosal barrier and gut microbiota modulation.
B. longum has been reported to exert an alleviative effect on colitis, but the results also suggested significant differences among strains. Here in this study, we compared the effect of B. longum subsp. longum strains with different properties in EPS production on DSS-induced colitis. To investigate the alleviative effect of a ropy-exopolysaccharide (EPS) producing strain, Bifidobacterium longum subsp. longum YS108R, on experimental colitis, C57BL/6J mice (male, 6-8 weeks old) were randomly assigned to six groups (n = 8): normal control, DSS colitis and four DSS colitis groups orally administered with three B. longum subsp. longum strains (YS108R, C11A10B and HAN4-25) and B. animalis subsp. lactis BB12, respectively, in which YS108R produced ropy-EPS, C11A10B produced non-ropy-EPS, HAN4-25 did not produce EPS and BB12 was set as a positive control. Ropy-EPS producing strain YS108R could alleviate the symptoms and remit inflammation induced by DSS, in which YS108R could decrease the pro-inflammatory cytokine IL-6 and IL-17A levels after DSS challenge (from 102 ± 45.22 to 37.95 ± 20.33 pg mL-1 and from 22.14 ± 5.43 to 12.58 ± 2.74, p < 0.05), but another non-ropy-EPS producing strain C11A10B did not decrease the levels of these pro-inflammatory cytokines. Furthermore, YS108R could maintain the expression levels of genes related to the mucosal barrier, but strain HAN4-25, a non-EPS producer, was not able to maintain the expression levels of these genes after DSS challenge. Analysis of gut microbiota showed that DSS treatment significantly increased the relative abundance of Enterobacteriaceae and Peptostreptococcaceae (0.2623 ± 0.162 and 0.0512 ± 0.0361) and decreased the relative abundance of S24-7 (0.042 ± 0.0326); however, YS108R administration could decrease the relative abundance of Enterobacteriaceae and Peptostreptococcaceae to 0.0848 ± 0.0399 and 0.0032 ± 0.0047 and increase the relative abundance of S24-7 to 0.2625 ± 0.0566 (p < 0.05). The results showed that B. longum subsp. longum YS108R could alleviate DSS-induced colitis by modulating the inflammation related cytokines, maintenance of the normal mucosal barrier and reverting the change of microbiota. Topics: Animals; Bifidobacterium longum; Colitis; Colon; Cytokines; Dextran Sulfate; Gastrointestinal Microbiome; Gene Expression Regulation; Intestinal Mucosa; Mice; Peroxidase; Polysaccharides, Bacterial; Real-Time Polymerase Chain Reaction; Tight Junction Proteins | 2019 |
Thymol reduces acetic acid-induced inflammatory response through inhibition of NF-kB signaling pathway in rat colon tissue.
The aim of the present study was to evaluate the anti-inflammatory effect of thymol in acetic acid-induced rat colitis through inhibiting the NF-κB signaling pathway.. Colitis was induced by intra-rectal administration of 2 mL of diluted acetic acid (4%) solution using a flexible plastic rubber catheter in Wistar rats. Colitis was induced on the first day and all treatments were applied 5 days after the induction of colitis. Thymol was dissolved in 0.2% tween 80 in saline and administered orally at doses of 10, 30, and 100 mg/kg per day. Macroscopic and histopathologic investigations were done. The expression of myeloperoxidase (MPO) and tumor necrosis factor-α (TNF-α) was determined by immunohistochemistry (IHC) assay. The protein expression level of pNF-κB p65 was measured by the Western blot technique.. Treatment with thymol reduced mucosal and histological damages compared to the acetic acid group. Our results showed that thymol markedly inhibited the production of MPO and TNF-α in the colon tissue of the acetic acid-induced group. In addition, thymol decreased acetic acid-induced up-regulation of pNFκB p65 protein.. The results of our study suggest that thymol exerts an anti-inflammatory effect in acetic acid-induced rat colitis by inhibiting the NF-κB signaling pathway and downregulating TNF-α and MPO expressions. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Colitis; Male; NF-kappa B; Peroxidase; Rats; Rats, Wistar; Signal Transduction; Thymol; Tumor Necrosis Factor-alpha | 2019 |
Probiotic Mixture VSL#3 Alleviates Dextran Sulfate Sodium-induced Colitis in Mice by Downregulating T Follicular Helper Cells.
Topics: Animals; Chronic Disease; Colitis; Colon; Dextran Sulfate; Gene Expression; Immunity, Humoral; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Lymph Nodes; Lymphocyte Count; Male; Mesentery; Mice; Mice, Inbred C57BL; Peroxidase; Probiotics; T-Lymphocytes, Helper-Inducer; Treatment Outcome | 2019 |
Therapeutic ultrasound attenuates DSS-induced colitis through the cholinergic anti-inflammatory pathway.
Ulcerative Colitis (UC) is an Inflammatory Bowel Disease (IBD) characterized by uncontrolled immune response, diarrhoea, weight loss and bloody stools, where sustained remission is not currently achievable. Dextran Sulphate Sodium (DSS)-induced colitis is an animal model that closely mimics human UC. Ultrasound (US) has been shown to prevent experimental acute kidney injury through vagus nerve (VN) stimulation and activation of the cholinergic anti-inflammatory pathway (CAIP). Since IBD patients may present dysfunctional VN activity, our aim was to determine the effects of therapeutic ultrasound (TUS) in DSS-induced colitis.. Acute colitis was induced by 2% DSS in drinking water for 7 days and TUS was administered to the abdominal area for 7 min/day from days 4-10. Clinical symptoms were analysed, and biological samples were collected for proteomics, macroscopic and microscopic analysis, flow cytometry and immunohistochemistry.. TUS attenuated colitis by reducing clinical scores, colon shortening and histological damage, inducing proteomic tolerogenic response in the gut during the injury phase and early recovery of experimental colitis. TUS did not improve clinical and pathological outcomes in splenectomised mice, while α7nAChR (α7 nicotinic acetylcholine receptor - indicator of CAIP involvement) knockout animals presented with disease worsening. Increased levels of colonic F4/80. These results indicate TUS improved DSS-induced colitis through stimulation of the splenic nerve along with possible contribution by VN with CAIP activation. FUND: Intramural Research Programs of the Clinical Centre, the National Institute of Biomedical Imaging and Bioengineering at the NIH and CAPES/Brazil. Topics: alpha7 Nicotinic Acetylcholine Receptor; Animals; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Humans; Inflammation; Inflammatory Bowel Diseases; Macrophages; Mice; Mice, Knockout; Peroxidase; Proteomics; Ultrasonic Therapy | 2019 |
The impact of dietary fermentable carbohydrates on a postinflammatory model of irritable bowel syndrome.
A low fermentable carbohydrate (FODMAP) diet is used in quiescent inflammatory bowel disease when irritable bowel syndrome-like symptoms occur. There is concern that the diet could exacerbate inflammation by modifying microbiota and short-chain fatty acid (SCFA) production. We examined the effect of altering dietary FODMAP content on inflammation in preclinical inflammatory models.. C57BL/6 mice were given 3% dextran sodium sulfate (DSS) in drinking water for 5 days and recovered for 3 weeks (postinflammatory, n = 12), or 5 days (positive-control, n = 12). Following recovery, DSS-treated or control mice (negative-control, n = 12) were randomized to 2-week low- (0.51 g/100 g total FODMAP) or high-FODMAP (4.10 g) diets. Diets mimicked human consumption containing fructose, sorbitol, galacto-oligosaccharide, and fructan. Colons were assessed for myeloperoxidase (MPO) activity and histological damage. Supernatants were generated for perforated patch-clamp recordings and cytokine measurement. Cecum contents were analyzed for microbiota, SCFA, and branched-chain fatty acids (BCFA). Data were analyzed by two-way ANOVA with Bonferroni.. Inflammatory markers were higher in the positive-control compared with negative-control and postinflammatory groups, but no differences occurred between the two diets within each treatment (MPO P > .99, histological scores P > .99, cytokines P > .05), or the perforated patch-clamp recordings (P > .05). Microbiota clustered mainly based on DSS exposure. No difference in SCFA content occurred. Higher total BCFA occurred with the low-FODMAP diet in positive-control (P < .01) and postinflammatory groups (P < .01).. In this preclinical study, reducing dietary FODMAPs did not exacerbate nor mitigate inflammation. Microbiota profile changes were largely driven by inflammation rather than diet. Low FODMAP intake caused a shift toward proteolytic fermentation following inflammation. Topics: Animals; Colitis; Cytokines; Dextran Sulfate; Dietary Carbohydrates; Disaccharides; Disease Models, Animal; Fatty Acids; Fatty Acids, Volatile; Fermentation; Gastrointestinal Microbiome; Hemiterpenes; Inflammation; Inflammatory Bowel Diseases; Irritable Bowel Syndrome; Isobutyrates; Mice; Monosaccharides; Nociception; Oligosaccharides; Patch-Clamp Techniques; Pentanoic Acids; Peroxidase; RNA, Ribosomal, 16S | 2019 |
Acetylsalicylic acid-tris-hydroxymethyl-aminomethane reduces colon mucosal damage without causing gastric side effects in a rat model of colitis.
We have developed a novel compound from acetylsalicylic acid (ASA) and 2-amino-2-(hydroxymethyl)-1,3-propanediol (Tris) precursors with ASA-like anti-inflammatory efficacy and reduced the mucosa-damaging side-effects. Our aim was to examine local and remote consequences of ASA-Tris administration in 2-,4-,6-trinitrobenzene-sulfonic acid (TNBS)-induced colitis as compared to ASA or mesalamine (5-aminosalicylate) treatment.. Sprague-Dawley rats were randomized to five groups (n = 6, each), and TNBS enemas were performed. Group 1 was the negative control; group 2 was the untreated colitis group. 12 hour after colitis induction repeated doses of ASA, ASA-Tris (both 0.55 mmol/kg) and mesalamine (0.77 mmol/kg) were given 3 times daily for 3 days to groups 3-5. On day 3 of colitis, the in vivo histology of the colon and stomach was investigated. Tissue xanthine-oxidoreductase, myeloperoxidase, nitrite/nitrate changes, and circulating TNF-alpha levels were measured. In addition, liver mitochondria were examined with high-resolution respirometry to analyze alterations in the electron transport chain.. TNBS enema significantly elevated inflammatory enzyme activities, NO production, TNF-alpha concentration, and induced morphological damage in the colon. ASA-treatment reduced the inflammatory marker levels and mucosal injury in the colon, but gastric tissue damage was present. ASA-Tris- and mesalamine-treatments significantly reduced the cytokine levels, inflammatory enzyme activities, and colonic mucosal damage without inducing gastric injury. Also, ASA significantly reduced the Complex IV-linked respiration of liver mitochondria, which was not observed after ASA-Tris-treatment.. As compared to ASA, ASA-Tris conjugation provides significant protection against the colonic injury and cytokine-mediated progression of inflammatory events in experimental colitis without influencing the gastric epithelial structure. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Colitis; Colon; Disease Models, Animal; Intestinal Mucosa; Male; Mesalamine; Methylamines; Nitrates; Nitrites; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2018 |
Thiadiazolidinone-8 Ameliorates Inflammation Associated with Experimental Colitis in Mice.
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, interleukin (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 TNBS-induced colitis in mice, and modulation of GSK-3β seems to be an interesting pharmacological target in colitis. Topics: Alanine Transaminase; Animals; Anti-Inflammatory Agents; Colitis; Colon; Cytokines; Glycogen Synthase Kinase 3 beta; Male; Mice; Peroxidase; Thiadiazoles; Trinitrobenzenesulfonic Acid | 2018 |
The Proton-activated Receptor GPR4 Modulates Intestinal Inflammation.
During active inflammation, intraluminal intestinal pH is decreased in patients with inflammatory bowel disease [IBD]. Acidic pH may play a role in IBD pathophysiology. Recently, proton-sensing G-protein coupled receptors were identified, including GPR4, OGR1 [GPR68], and TDAG8 [GPR65]. We investigated whether GPR4 is involved in intestinal inflammation.. The role of GPR4 was assessed in murine colitis models by chronic dextran sulphate sodium [DSS] administration and by cross-breeding into an IL-10 deficient background for development of spontaneous colitis. Colitis severity was assessed by body weight, colonoscopy, colon length, histological score, cytokine mRNA expression, and myeloperoxidase [MPO] activity. In the spontaneous Il-10-/- colitis model, the incidence of rectal prolapse and characteristics of lamina propria leukocytes [LPLs] were analysed.. Gpr4-/- mice showed reduced body weight loss and histology score after induction of chronic DSS colitis. In Gpr4-/-/Il-10-/- double knock-outs, the onset and progression of rectal prolapse were significantly delayed and mitigated compared with Gpr4+/+/Il-10-/- mice. Double knock-out mice showed lower histology scores, MPO activity, CD4+ T helper cell infiltration, IFN-γ, iNOS, MCP-1 [CCL2], CXCL1, and CXCL2 expression compared with controls. In colon, GPR4 mRNA was detected in endothelial cells, some smooth muscle cells, and some macrophages.. Absence of GPR4 ameliorates colitis in IBD animal models, indicating an important regulatory role in mucosal inflammation, thus providing a new link between tissue pH and the immune system. Therapeutic inhibition of GPR4 may be beneficial for the treatment of IBD. Topics: Animals; Chemokine CCL2; Chemokine CXCL1; Chemokine CXCL2; Colitis; Dextran Sulfate; Endothelial Cells; Female; Hydrogen-Ion Concentration; Interferon-gamma; Interleukin-10; Intestinal Mucosa; Macrophages; Male; Mice; Mice, Knockout; Myocytes, Smooth Muscle; Nitric Oxide Synthase Type II; Peroxidase; Protons; Receptors, G-Protein-Coupled; Rectal Prolapse; RNA, Messenger; T-Lymphocytes, Helper-Inducer | 2018 |
4-methylesculetin, a coumarin derivative, ameliorates dextran sulfate sodium-induced intestinal inflammation.
4-methylesculetin is one of the coumarin derivatives with great anti-oxidant and anti-inflammatory activities. Recent studies have shown that 4-methylesculetin has a promising potentiality to treat inflammatory diseases, especially those related to reactive oxygen species, as inflammatory bowel disease. Based on this, the present study aims to investigate the intestinal anti-inflammatory activity of 4-methylesculetin in dextran sulfate sodium (DSS) model. For this purpose, mice received DSS 5% for 5 days followed by 2 days of filtered tap water. Treated groups received orally 5 or 25 mg/kg of 4-methylesculetin daily since the first day. Macroscopic, microscopic and biochemical parameters were evaluated. 4-methylesculetin (25 mg/kg) improved microscopic parameters, decreased MPO activity, reduced the colonic levels of IL-6 and counteracted GSH depletion when compared with DSS-control group. Our results show the intestinal anti-inflammatory activity of 4-methylesculetin in DSS model, which is related to its antioxidant and anti-inflammatory properties. This way, 4-methylesculetin, is a new potential compound for treatment of both types of IBD. Topics: Animals; Colitis; Colon; Coumarins; Dextran Sulfate; Enzyme-Linked Immunosorbent Assay; Glutathione; Interleukin-17; Interleukin-6; Male; Mice; Peroxidase; Tumor Necrosis Factor-alpha; Umbelliferones | 2018 |
The protective effects of magnolol on acute trinitrobenzene sulfonic acid‑induced colitis in rats.
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. Topics: Acute Disease; Animals; Biphenyl Compounds; Colitis; Cyclooxygenase 2; Down-Regulation; Enzyme-Linked Immunosorbent Assay; Interleukin-17; Interleukin-6; Lignans; Male; Nitric Oxide Synthase Type II; Peroxidase; Protective Agents; Rats; Rats, Wistar; Spleen; Thymus Gland; Toll-Like Receptor 4; Transcription Factor RelA; Trinitrobenzenesulfonic Acid | 2018 |
Effects of quercitrin on bacterial translocation in a rat model of experimental colitis.
This study aimed to analyze the effects of quercitrin, which has anti-inflammatory properties, on bacterial translocation in inflammatory bowel diseases by using an experimental colitis model.. Forty male Wistar-Albino rats were used in the study. Rats were divided into 4 groups (control, colitis, treatment 1 and 2 groups). The rats in the control group were given normal drinking water. In the colitis group, colitis was induced by 5% DSS in drinking water. The control and colitis groups underwent operation on Day 7. In the 2 treatment groups, 5% DSS was added to drinking water for the first 7 days and the groups were treated with quercitrin at the doses of 1 and 5 mg/kg/day for the following 10 days. Treatment groups operated on Day 18. Blood samples were taken for blood culture and left colectomy was performed. The inflammation in the colon was macroscopically and microscopically evaluated and graded. Tissue samples were taken (liver, spleen and mesenteric lymph nodes (MLN)) for tissue culturing in order to assess bacterial translocation. Tissue myeloperoxidase (MPO), serum tumor necrosis factor-alpha (TNF-α) and plasma endotoxin levels were measured.. When the control and colitis groups were compared, observed that colitis was induced by DSS (p < 0.05). When the colitis and treatment groups were compared, it was found that quercitrin had a significant therapeutic effect (p < 0.05).. In the experimental colitis model established by using DSS, treatment with quercitrin resulted in a histopathological improvement and reduction in biochemical parameters, inflammation and in bacterial translocation (p < 0.05). Topics: Animals; Anti-Inflammatory Agents; Bacterial Translocation; Biomarkers; Colitis; Colon; Disease Models, Animal; Endotoxins; Inflammation; Male; Peroxidase; Quercetin; Rats; Tumor Necrosis Factor-alpha | 2018 |
Inflamed site-specific drug delivery system based on the interaction of human serum albumin nanoparticles with myeloperoxidase in a murine model of experimental colitis.
To develop a new strategy for inflamed site-specific drug delivery in the colon for the treatment of ulcerative colitis (UC), we leveraged on the interaction between myeloperoxidase (MPO) and human serum albumin (HSA) and prepared nanoparticles (HSA NPs) conjugated with 5-aminosalicylic acid (5-ASA). The 5-ASA-HSA NPs (nine molecules of 5-ASA per HSA molecule) were uniform particles with an average particle size of 190 nm, a zeta potential of --11.8 mV, and a polydispersity index of 0.35. This was considered a suitable particle characteristic to pass through the mucus layer and accumulate into the mucosa. The specific interaction between the 5-ASA-HSA NPs and MPO was observed using quartz crystal microbalance analysis in vitro. In addition, the 5-ASA-HSA NPs group containing one thousandth of the dose of the 5-ASA (75 μg/kg) showed significantly lower disease activity index values and colon weight/length ratios in UC model mice as similar to large amount of neat 5-ASA group (75 mg/kg), indicating that the therapeutic effect of the 5-ASA-HSA NP formulation was confirmed in vivo. Microscopic images of tissue sections of colon extracted from UC model mice demonstrated that HSA NPs and MPO were both localized in the colon, and this specific interaction between HSA NPs and MPO would be involved the in the therapeutic effect in vivo. Furthermore, in the 5-ASA and 5-ASA-HSA NPs groups, some inflammatory damage was observed in the colon, but the degree of damage was mild compared with the control and HSA NPs groups, suggesting mucosal repair and replacement with fibrous granulation tissue had occurred. Therefore, these data demonstrated that an HSA NP formulation has the potential to specifically deliver 5-ASA to an inflamed site where MPO is highly expressed. Topics: Animals; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Delivery Systems; Drug Interactions; Humans; Male; Mice; Mice, Inbred BALB C; Nanoparticles; Peroxidase; Random Allocation; Serum Albumin, Human | 2018 |
N-Methylcytisine Ameliorates Dextran-Sulfate-Sodium-Induced Colitis in Mice by Inhibiting the Inflammatory Response.
Topics: Alkaloids; Animals; Anti-Inflammatory Agents; Biomarkers; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; I-kappa B Proteins; Inflammation Mediators; Intestinal Mucosa; Mice; Peroxidase; Quinolizines | 2018 |
A Novel Topical PPARγ Agonist Induces PPARγ Activity in Ulcerative Colitis Mucosa and Prevents and Reverses Inflammation in Induced Colitis Models.
Peroxisome proliferator-activated receptor-gamma (PPARγ) exerts anti-inflammatory effects and is therefore a potential target in ulcerative colitis (UC). A novel PPARγ agonist (AS002) developed for local action was evaluated ex vivo in biopsies from UC patients and in vivo in mice with low-grade dextran sodium sulfate (DSS)- and trinitrobenzene sulfonic acid (TNBS)-induced colitis.. Colonic biopsies from UC patients (n = 18) and healthy controls (n = 6) were incubated with AS002 or rosiglitazone (positive control) to measure mRNA expression of the PPARγ-responsive gene ADIPOPHILIN and protein levels of UC-related cytokines (enzyme-linked immunosorbent assay). AS002 absorption was determined in the colonic mucosa of UC patients. DSS-colitis mice received PPARγ agonists or vehicle daily by intrarectal administration starting 2 days before induction of colitis (preventive) or from days 3 to 8 (curative). Myeloperoxidase (MPO) and cytokine levels in colonic mucosa were determined. In addition, AS002 effects were studied in TNBS colitis.. AS002 displayed an absorption pattern of a lipophilic drug totally metabolized in the mucosa. AS002 and rosiglitazone increased ADIPOPHILIN mRNA expression (3-fold) and decreased TNF-α, IL-1β, and IL-13 levels in human UC biopsies. In DSS, in both preventive and curative treatment and in TNBS colitis, AS002 protected against macroscopic and histological damage and lowered MPO and TNF-α, IL-1β, and IL-13 levels.. AS002 triggers anti-inflammatory PPARγ activity in the human colonic mucosa of UC patients and prevents and reverses colitis in mice. Our data suggest that AS002 has potential for topical maintenance treatment of UC, which warrants further studies in vivo in patients. Topics: Adult; Aged; Animals; Colitis; Colitis, Ulcerative; Colon; Cytokines; Dextran Sulfate; Female; Humans; Intestinal Mucosa; Male; Mice, Inbred BALB C; Middle Aged; Perilipin-2; Peroxidase; PPAR gamma; Rosiglitazone; Trinitrobenzenesulfonic Acid | 2018 |
Colon-targeted delivery of cyclosporine A using dual-functional Eudragit
Colon-targeted oral nanoparticles (NPs) have emerged as an ideal, safe, and effective therapy for ulcerative colitis (UC) owing to their ability to selectively accumulate in inflamed colonic mucosa. Cyclosporine A (CSA), an immunosuppressive agent, has long been used as rescue therapy in severe steroid-refractory UC. In this study, we developed CSA-loaded dual-functional polymeric NPs composed of Eudragit. CSA-loaded Eudragit FS30D nanoparticles (ENPs), PLGA nanoparticles (PNPs), and Eudragit FS30D/PLGA nanoparticles (E/PNPs) were prepared using the oil-in-water emulsion method. Scanning electron microscope images and zeta size data showed successful preparation of CSA-loaded NPs.. PNPs exhibited a burst drug release of >60% at pH 1.2 (stomach pH) in 0.5 h, which can lead to unwanted systemic absorption and side effects. ENPs effectively inhibited the burst drug release at pH 1.2 and 6.8 (proximal small intestine pH); however, nearly 100% of the CSA in ENPs was released rapidly at pH 7.4 (ileum-colon pH) owing to complete NP dissolution. In contrast to single-functional PNPs and ENPs, the dual-functional E/PNPs minimized burst drug release (only 18%) at pH 1.2 and 6.8, and generated a sustained release at pH 7.4 thereafter. Importantly, in distribution studies in the gastrointestinal tracts of mice, E/PNPs significantly improved CSA distribution to the colon compared with PNPs or ENPs. In a mouse model of colitis, E/PNP treatment improved weight loss and colon length, and decreased rectal bleeding, spleen weight, histological scoring, myeloperoxidase activity, macrophage infiltration, and expression of proinflammatory cytokines compared with PNPs or ENPs.. Overall, this work confirms the benefits of CSA-loaded E/PNPs for efficiently delivering CSA to the colon, suggesting their potential for UC therapy. Topics: Administration, Oral; Animals; Body Weight; Colitis; Colon; Cyclosporine; Cytokines; Drug Carriers; Drug Delivery Systems; Drug Liberation; Hydrogen-Ion Concentration; Immunosuppressive Agents; Inflammation Mediators; Lactic Acid; Macrophages; Methylmethacrylates; Mice, Inbred ICR; Nanoparticles; Particle Size; Peroxidase; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Treatment Outcome | 2018 |
Berberrubine attenuates mucosal lesions and inflammation in dextran sodium sulfate-induced colitis in mice.
Ulcerative colitis (UC) is a chronic relapsing disease without satisfactory treatments, in which intestinal inflammation and disrupted intestinal epithelial barrier are two main pathogeneses triggering UC. Berberrubine (BB) is deemed as one of the major active metabolite of berberine (BBR), a naturally-occurring isoquinoline alkaloid with appreciable anti-UC effect. This study aimed to comparatively investigate the therapeutic effects of BB and BBR on dextran sodium sulfate (DSS)-induced mouse colitis model, and explore the potential underlying mechanism. Results revealed that BB (20 mg/kg) produced a comparable therapeutic effect as BBR (50 mg/kg) and positive control sulfasalazine (200 mg/kg) by significantly reducing the disease activity index (DAI) with prolonged colon length and increased bodyweight as compared with the DSS group. BB treatment was shown to significantly ameliorate the DSS-induced colonic pathological alternations and decreased histological scores. In addition, BB markedly attenuated colonic inflammation by alleviating inflammatory cell infiltration and inhibiting myeloperoxidase (MPO) and cytokines (TNF-α, IFN-γ, IL-1β, IL-6, IL-4 and IL-10) productions in DSS mice. Furthermore, BB treatment substantially upregulated the expression of tight junction (TJ) proteins (zonula occludens-1, zonula occludens-2, claudin-1, occludin) and mRNA expression of mucins (mucin-1 and mucin-2), and decreased the Bax/Bcl-2 ratio. In summary, BB exerted similar effect to its analogue BBR and positive control in attenuating DSS-induced UC with much lower dosage and similar mechanism. The protective effect observed may be intimately associated with maintaining the integrity of the intestinal mucosal barrier and mitigating intestinal inflammation, which were mediated at least partially, via favorable modulation of TJ proteins and mucins and inhibition of inflammatory mediators productions in the colonic tissue. This is the first report to demonstrate that BB possesses pronounced anti-UC effect similar to BBR and sulfasalazine with much smaller dosage. BB might have the potential to be further developed into a promising therapeutic option in the treatment of UC. Topics: Animals; Berberine; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Inflammation; Intestinal Mucosa; Male; Mice; Mice, Inbred BALB C; Peroxidase; Tight Junction Proteins; Tight Junctions | 2018 |
MicroRNA-146a-5p attenuates visceral hypersensitivity through targeting chemokine CCL8 in the spinal cord in a mouse model of colitis.
Visceral pain, observed in inflammatory bowel disease (IBD) patients, is a challenging medical problem and remains poorly understood because the mechanisms underlying it are unclear. Emerging evidence indicates that microRNAs (miRNAs) play a crucial role in the pathogenesis of acute and chronic pain. In this study, we aimed to explore the potential role of miR-146a-5p (the mature form of miR-146a) in a mouse model of colitis induced by intracolonic injection of trinitrobenzene sulfonic acid (TNBS). We found that induction of colitis resulted in visceral hyperalgesia manifested by a decreased pain threshold to colorectal distension and upregulation of miR-146a-5p expression in the lumbosacral spinal cord. In situ hybridization and immunohistochemistry results showed that miR-146a-5p was colocalized with neuronal marker NeuN, but not with astrocytic marker GFAP or microglial marker IBA-1. Dual-luciferase reporter assay showed that miR-146a-5p directly targeted the 3'-untranslated region (UTR) of CCL8, which was previously identified as an important regulator of visceral pain. In cultured Neuro-2a cells, TNF-α-induced CCL8 upregulation was decreased by transfection of miR-146a-5p mimic dose-dependently. In vivo, exogenous supplementation of miR-146a-5p by intrathecal miR-146a-5p agomir significantly alleviated visceral pain and decreased CCL8 expression in colitis mice. Furthermore, inhibition of CCL8 expression by CCL8 siRNA relieved colitis-induced visceral nociception. Finally, in naïve mice intrathecal miR-146a-5p antagomir upregulated CCL8 expression and induced visceral pain hypersensitivity, which could be partially rescued by neutralization of CCL8. Taken together, the present findings indicate that miR-146a-5p may be an endogenous suppressor of visceral pain and exogenous supplementation of miR-146a-5p could exert an analgesic effect at least partly by targeting spinal CCL8 expression. Thus, miR-146a-5p may serve as a novel therapeutic target for visceral pain intervention in the context of colitis. Topics: Animals; Antagomirs; Antibodies; Cells, Cultured; Chemokine CCL8; Colitis; Disease Models, Animal; Gene Expression Regulation; Humans; Hyperalgesia; Male; Mice; Mice, Inbred C57BL; MicroRNAs; Peroxidase; RNA, Small Interfering; Spinal Cord; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Up-Regulation; Visceral Pain | 2018 |
Brazilian green propolis hydroalcoholic extract reduces colon damages caused by dextran sulfate sodium-induced colitis in mice.
This study investigated the effects of Brazilian green propolis hydroalcoholic extract (BPE) in 3% w/v dextran sodium sulfate (DSS)-induced colitis in mice. The effects of BPE (3, 30 and 300 mg/kg, p.o, by 7 days) on the morphological (colon length and colon weight), clinical (disease activity index and weight loss), microscopic (histological score and mucin levels) and biochemical parameters were determined. The effects of BPE (300 mg/kg, p.o) in the gastrointestinal transit of mice were also evaluated. As expected, the DSS ingestion damaged the colonic tissue, lowered the body weight, decreased the mucin levels, increased MPO activity, reduced SOD activity and GSH amount. In contrast, the treatment with BPE (300 mg/kg) significantly reduced macroscopic colonic injury and the mucosal damage in colon on histopathological examination and reversed the decrease in mucin levels induced by DSS. It also significantly normalized the SOD activity and the levels of GSH, but did not elicit any effect on MPO activity in the colon. In addition, BPE did not change the gastric emptying or the intestinal transit rate of mice. Together, these results suggested that BPE reduced the signs of DSS-induced colitis in mice through maintenance of intestinal mucin barrier and favoring intestinal antioxidant defenses. Topics: Animals; Brazil; Colitis; Colon; Dextran Sulfate; Female; Gastrointestinal Transit; Mice; Mucins; Peroxidase; Propolis; Superoxide Dismutase | 2018 |
Black rice anthocyanin-rich extract and rosmarinic acid, alone and in combination, protect against DSS-induced colitis in mice.
The aim of this study was to investigate the effect of black rice anthocyanin-rich extract (BRAE) and rosmarinic acid (RA), alone and in combination, on dextran sulfate sodium (DSS)-induced colitis in mice. Results showed that administration of BRAE and RA, alone and in combination, significantly decreased the disease activity index (DAI) and the histological score of colons in DSS-induced colitis mice. Moreover, the administration of BRAE and RA, alone and in combination, not only reduced myeloperoxidase (MPO) and nitric oxide (NO) levels, but also inhibited the expression of pro-inflammatory mediators including interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2. Our results showed that BRAE decreased the histological score and TNF-α mRNA expression in a dose-dependent manner, while BRAE + RA dose-dependently attenuated the histological score and mRNA expression of IL-6. However, the benefits of RA were not dose-dependent within the dose range of 25-100 mg kg-1. The combination of BRAE and RA showed better inhibitory effect on the NO content and iNOS mRNA expression than BRAE or RA given alone, and was the most effective in ameliorating DSS-induced colitis at 100 mg kg-1. Notably, the BRAE and RA combination exhibited additive interactions in reducing MPO and NO levels, as well as the expression of some pro-inflammatory mediators (IL-6, IL-1β and iNOS), especially at 100 mg kg-1. In conclusion, dietary BRAE and RA, alone and in combination, alleviate the symptoms and inflammation of DSS-induced colitis in mice, and may provide a promising dietary approach for the management of inflammatory bowel disease. Topics: Animals; Anthocyanins; Cinnamates; Colitis; Cyclooxygenase 2; Depsides; Dextran Sulfate; Drug Therapy, Combination; Female; Humans; Interleukin-1beta; Interleukin-6; Mice; Mice, Inbred C57BL; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Oryza; Peroxidase; Plant Extracts; Rosmarinic Acid | 2018 |
Enhanced biopharmaceutical effects of tranilast on experimental colitis model with use of self-micellizing solid dispersion technology.
Topics: Administration, Oral; Animals; Anti-Infective Agents; Biological Availability; Colitis; Colon; Disease Models, Animal; Drug Carriers; Drug Compounding; Gastrointestinal Agents; Hydrogen-Ion Concentration; Intestinal Mucosa; Male; Micelles; Neutrophil Infiltration; ortho-Aminobenzoates; Particle Size; Peroxidase; Rats, Sprague-Dawley; Solubility; Technology, Pharmaceutical; Trinitrobenzenesulfonic Acid | 2018 |
Frondanol, a Nutraceutical Extract from
Topics: Animals; Antigens, Differentiation; Chemokine CXCL2; Colitis; Complex Mixtures; Cucumaria; Cytokines; Dextran Sulfate; Dietary Supplements; Gene Expression Regulation; Male; Mice; Mice, Inbred C57BL; Peroxidase; RNA, Messenger | 2018 |
Effect of Eucommia ulmoides Leaf Extract on Chronic Dextran Sodium Sulfate-Induced Colitis in Mice.
Ulcerative colitis (UC) is a refractory disease that causes chronic inflammation or ulceration in the mucosa of the large intestine with multiple relapses. Although several drugs, including 5-aminosalicylic acid, steroids, immunosuppressants, and infliximab, are used for UC therapy, patients suffer from side effects of these drugs, and a new safer therapeutic agent is desired. Eucommia ulmoides OLIV. leaf extract (ELE) has an anti-inflammatory effect. Therefore, we examined the effect of ELE on UC using a chronic dextran sulfate sodium (DSS)-induced colitis model in mice. Chronic DSS-induced colitis was triggered by alternately repeating 5 days' DSS and 7 days' water administration in mice for 29 d. The severity of DSS-induced colitis was evaluated by daily body weight and bloody stool score, and colon length and myeloperoxidase (MPO) activity in colon tissue on day 29. ELE (3 or 9%) was administered in combination by feeding for 29 d, and the effect on colitis was evaluated. The mice given DSS exhibited chronic colitis symptoms with body weight loss, increased bloody stool score and MPO activity, and shortened colon length. Administration of 3 or 9% ELE suppressed the body weight loss, bloody stool score, colon shortening, and MPO activity in a dose-dependent manner. Histological analysis showed that the ELE-treated mice had less damages and leukocyte infiltration in the mucosal layer of the large intestine compared to DSS alone group. These results suggested that ELE has the potential to prevent the development of DSS-induced colitis and a therapeutic effect on UC in a safe manner. Topics: Animals; Colitis; Colon; Dextran Sulfate; Eucommiaceae; Male; Mice, Inbred ICR; Peroxidase; Phytotherapy; Plant Extracts; Plant Leaves | 2018 |
Portulacaoleraceal extract alleviates trinitrobenzene sulfonic acid-induced colitis in rats.
Portulacaoleraceal (POL) has been widely used as an edible plant and a folk medicine in many countries, due to its several health benefits. This study examined the effects of POL on trinitrobenzene sulfonic acid (TNBS)-induced colitis via enema administration. Sixty male Sprague-Dawley rats were randomly divided into five groups: untreated, TNBS, TNBS + POL 10 g/kg, TNBS + POL 5 g/kg and TNBS + POL 2.5 g/kg groups. Rats were subjected to enema treatment once a day for 10 consecutive days with POL extract or distilled water after induction of TNBS. The changes of body weight, histological parameters, myeloperoxidase (MPO), superoxide dismutase (SOD), nitric oxide synthase activity (NOS), malondialdehyde (MDA) and nitric oxide (NO) levels in colon tissues were investigated. After POL extract treatment, body weights of rats significantly increased, macroscopic and microscopic damage scores reduced, MPO and NOS activity, as well as MDA and NO level significantly decreased, while SOD activity increased in a dose-dependent manner in the TNBS + POL groups compared with the TNBS group. Our results demonstrated that POL enema treatment attenuated pathologic changes of TNBS-induced colitis in rats through restoring colonic damage and reducing inflammatory response in the intestine. Thus, POL enema might be considered as a potential effective treatment for ulcerative colitis patients. Topics: Animals; Body Weight; Colitis; Colon; Male; Malondialdehyde; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Plant Extracts; Portulacaceae; Rats, Sprague-Dawley; Superoxide Dismutase; Trinitrobenzenesulfonic Acid | 2018 |
Treatment with Trichilia catigua ethyl-acetate fraction improves healing and reduces oxidative stress in TNBS-induced colitis in rats.
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. Topics: Acetates; Administration, Oral; Animals; Biomarkers; Body Weight; Colitis; Colon; Inflammation; Male; Meliaceae; Myenteric Plexus; Neurons; Oxidative Stress; Peroxidase; Plant Extracts; Rats, Wistar; Trinitrobenzenesulfonic Acid; Wound Healing | 2018 |
Colon-targeted dexamethasone microcrystals with pH-sensitive chitosan/alginate/Eudragit S multilayers for the treatment of inflammatory bowel disease.
Oral colon-targeted drug delivery has gained popularity as an effective strategy for treatment of inflammatory bowel disease (IBD). In this study, we prepared colon-targeted dexamethasone microcrystals (DXMCs) coated with multilayers of chitosan oligosaccharide (CH), alginate (AG), and finally Eudragit S 100 (ES) (ES Topics: Alginates; Animals; Anti-Inflammatory Agents; Chitosan; Colitis; Colon; Cytokines; Dexamethasone; Dextran Sulfate; Drug Delivery Systems; Drug Liberation; Glucuronic Acid; Hexuronic Acids; Hydrogen-Ion Concentration; Male; Mice, Inbred ICR; Peroxidase; Polymethacrylic Acids | 2018 |
Tussilagone, a major active component in Tussilago farfara, ameliorates inflammatory responses in dextran sulphate sodium-induced murine colitis.
Inflammatory bowel disease (IBD) is a chronically relapsing inflammatory disorder of the gastrointestinal tract. Current IBD treatments are associated with poor tolerability and insufficient therapeutic efficacy, prompting the need for alternative therapeutic approaches. Recent advances suggest promising interventions based on a number of phytochemicals. Herein, we explored the beneficial effects of tussilagone, a major component of Tussilago farfara, in mice subjected to acute colitis induced by dextran sulfate sodium (DSS). Treatment with tussilagone resulted in a significant protective effect against DSS-induced acute colitis in mice via amelioration of weight loss, and attenuation of colonic inflammatory damage. Additionally, the expression of tumor necrosis factor-α and interleukin-6 and the activity of myeloperoxidase in colonic tissues were significantly reduced in tussilagone-treated mice. Furthermore, immunohistochemical analysis revealed that tussilagone treatment reduced the numbers of nuclear factor-kappa B (NF-κB) and increased the numbers of nuclear factor erythroid 2-related factor 2 (Nrf2) in nuclei of colonic tissues. Taken together, tussilagone treatment attenuated DSS-induced colitis in mice through inhibiting the activation of NF-κB and inducing Nrf2 pathways, indicating that tussilagone is a potent therapeutic candidate for treatment of intestinal inflammation. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Heme Oxygenase-1; Interleukin-6; Mice; Mice, Inbred BALB C; NF-E2-Related Factor 2; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Sesquiterpenes; Tumor Necrosis Factor-alpha; Tussilago | 2018 |
Effect of hesperetin on inflammatory and oxidative status in trinitrobenzene sulfonic acid-induced experimental colitis model.
In our study, the effect of hesperetin on inflammatory and oxidative status in trinitrobenzene sulfonic acid (TNBS)-induced experimental colitis model was investigated through different methods. Eighteen Wistar albino male rats were divided in to three groups: Group I (Control, n = 8; 1 ml physiological saline), Group II (Colitis, n = 8; 1 ml TNBS), Group III (Hesperetin, n = 8; 1 ml TNBS and 100 mg/kg hesperetin). Macroscopic and microscopic scores were calculated to determine the damage to the colon at the end of the experiment. Serum tumor necrosis factor-α (TNF-α) and tissue interleukin-6 (IL-6) levels were determined using the ELISA method. Myeloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels were investigated spectrophotometrically. The TUNEL method was used for the detection of apoptotic cells in the colon tissue. Inducible nitric oxide synthase (iNOS) and nuclear factor-kappa-B (NF-ĸβ) expression in the colon were determined immunohistochemically. Hesperetin administration has shown to significantly reduce levels of MPO, MDA, and proinflammatory agents (TNF-α, IL-6, and NF-ĸβ). It has also been proven to inhibit mucosal apoptosis. This study indicates that hesperetin is protective against TNBS-induced colitis model via antiinflammatory, antioxidant and antiapoptotic effects. Topics: Animals; Antioxidants; Colitis; Enzyme-Linked Immunosorbent Assay; Hesperidin; Immunohistochemistry; In Situ Nick-End Labeling; Interleukin-6; Lipid Peroxidation; Male; Malondialdehyde; NF-kappa B; Nitric Oxide Synthase Type II; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Superoxide Dismutase; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2018 |
Lactobacillus reuteri F-9-35 Prevents DSS-Induced Colitis by Inhibiting Proinflammatory Gene Expression and Restoring the Gut Microbiota in Mice.
Ulcerative colitis (UC) is the most common inflammatory bowel diseases and there is still a lack of safe and effective treatments. Consumption of L. reuteri F-9-35 may effective in preventing human UC. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Female; Gastrointestinal Microbiome; Gene Expression Profiling; Gene Expression Regulation; Inflammation; Inflammatory Bowel Diseases; Interleukin-6; Limosilactobacillus reuteri; Mice; Peroxidase; Phenotype; Probiotics; Tumor Necrosis Factor-alpha | 2018 |
Lactobacillus plantarum CQPC06 Activity Prevents Dextran Sulfate Sodium-Induced Colitis by Regulating the IL-8 Pathway.
Lactobacillus plantarum CQPC06 (LP-CQPC06) is a newly discovered lactic acid bacterial strain. Here, the beneficial effects of this strain on C57BL/6J mice with dextran sulfate sodium-induced colitis were investigated. LP-CQPC06 was more resistant to gastric acid and bile salts than L. delbrueckii subsp. bulgaricus (LB). In the DSS-induced colitis mouse model, LP-CQPC06 treatment decreased the colon weight/length ratio and increased the colon length as compared to untreated mice with DSS-induced colitis. LP-CQPC06 also reduced the serum levels of interleukin 8 (IL-8), IL-1, tumor necrosis factor alpha, and macrophage inflammatory protein-1 alpha, as well as reducing levels of myeloperoxidase (MPO) and nitric oxide (NO) in the colon tissues of mice with DSS-induced colitis. In all cases, the effects of LP-CQPC06 were significantly stronger than those of LB. Quantitative polymerase chain reactions and western blots indicated that LP-CQPC06 increased the mRNA and protein expression levels of neuronal nitric oxide synthase, endothelial nitric oxide synthase, and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha, while decreasing the expression levels of inducible nitric oxide synthase, nuclear factor kappa-beta, C-X-C motif chemokine receptor 1 (CXCR1), and CXCR2. Thus, L. plantarum CQPC06 had a good protective effect against colitis in a mouse model via the IL-8 pathway. Therefore, L. plantarum CQPC06 might have potential uses as a probiotic for colonic protection.. In this study, a newly discovered lactic acid bacteria was investigated. This bacterial strain had a good prophylactic effect against colitis in a mouse model, and might have potential utility as a probiotic. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Interleukin-8; Lactobacillus plantarum; Male; Mice; Mice, Inbred C57BL; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Probiotics; Tumor Necrosis Factor-alpha | 2018 |
Oenothera rosea L´Hér. ex Ait attenuates acute colonic inflammation in TNBS-induced colitis model in rats: in vivo and in silico myeloperoxidase role.
Oenothera rosea L´Hér. ex Ait is a species traditionally used in the treatment of inflammation, headache, stomach pain, infections, among others. The aim of this study was evaluating the acute anti-inflammatory activity of the aqueous extract of O. rosea by 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Rats were randomized into six groups: (I) Sham; (II) EtOH; (III) TNBS; and (IV-VI) 250, 500 and 750 mg/Kg, respectively. The colonic injury was induced (groups III-VI) by intrarectal instillation of 0.25 mL of TNBS (10 mg) in 50% ethanol. Groups I and II received an enema (0.25 mL) of physiological saline solution or 50% ethanol, respectively. Treatments were administered by oral gavage 48, 24 and 1 h prior, and 24 h after the induction. The inflammatory response was assessed considering the macroscopic and microscopic damage, the serum nitric oxide (NO), the colonic IL-1β levels, and the myeloperoxidase (MPO) activity. Moreover, we performed an LC-MS-based metabolite profiling, and a docking on the MPO. Doses of 500 and 750 mg/Kg showed a protective effect in the TNBS-induced colonic damage. This activity was related to the downregulation of evaluated parameters. Also, considering previous reports, 29 metabolites of 91 detected were selected for the docking, of which Isolimonic acid (29) and Kaempferol 3-(2'',4''-diacetylrhamnoside) (10) showed the highest affinity to MPO. The aqueous extract of O. rosea protected the TNBS-induced colonic damage in rats, an effect that could be associated with the presence of polyphenolic compounds, alkaloids, and terpenes; as well as their ability to down-regulate MPO activity. Topics: Animals; Colitis; Colon; Disease Models, Animal; Down-Regulation; Female; Inflammation; Interleukin-1beta; Intestinal Mucosa; Nitric Oxide; Oenothera; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2018 |
Isolation and Characterization of Potentially Probiotic Bacterial Strains from Mice: Proof of Concept for Personalized Probiotics.
Modulation of the gut microbiota through the use of probiotics has been widely used to treat or prevent several intestinal diseases. However, inconsistent results have compromised the efficacy of this approach, especially in severe conditions such as inflammatory bowel disease (IBD). The purpose of our study was to develop a personalized probiotic strategy and assess its efficacy in a murine model of intestinal inflammation. Commensal bacterial strains were isolated from the feces of healthy mice and then administered back to the host as a personalized treatment in dextran sodium sulfate (DSS)-induced colitis. Colonic tissues were collected for histological analysis and to investigate inflammatory markers such as Topics: Animals; Bifidobacterium; Biomarkers; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Drug Resistance, Multiple, Bacterial; Gastrointestinal Microbiome; Inflammation; Inflammatory Bowel Diseases; Intestines; Lactobacillus; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Peroxidase; Probiotics | 2018 |
Intestinal Anti-Inflammatory Activity of the Aqueous Extract from Ipomoea asarifolia in DNBS-Induced Colitis in Rats.
Inflammatory bowel disease is triggered by an uncontrolled immune response associated with genetic, environmental, and intestinal microbiota imbalance. Ipomoea asarifolia (IA), popularly known as "salsa" or "brave salsa", belongs to the Convolvulaceae family. The aim of this approach was to study the preventive effect of IA aqueous extract in 2,4-dinitrobenzene sulfonic acid (DNBS)-induced colitis in rats. Rats pretreated with IA extract or sulfasalazine (SSZ) received intracolonic instillation of DNBS in 50% ethanol (v/v). IA extract presented a protective effect against intestinal inflammation, with improvement in the disease activity index and macroscopic damage. IA or SSZ significantly reduced myeloperoxidase activity, and also down-regulation of the gene expression of JNK1, NF-κβ-p65, STAT3, and decreased levels of TNFα, IL-1β, and increased IL-10, associated with a significant improvement of oxidative stress, in addition to a reduction in MDA and an increase of glutathione in colonic tissue. The protective effect of the extract was also confirmed in histological evaluation, showing preservation of the colonic cytoarchitecture. Immunohistochemical analysis revealed down-regulation of NF-κβ-p65, iNOS, IL-17, and up-regulation of SOCs-1 and MUC-2. IA extract presents antioxidant and anti-inflammatory intestinal properties, and proved to be a potential application for preventing damage induced by DNBS. Topics: Animals; Anti-Inflammatory Agents; Colitis; Cytokines; Dinitrofluorobenzene; Female; Gene Expression Regulation; Intestines; Ipomoea; Mitogen-Activated Protein Kinase 8; NF-kappa B; Organ Size; Oxidative Stress; Peroxidase; Plant Extracts; Rats, Wistar; STAT3 Transcription Factor | 2018 |
Treatment with P28GST, a schistosome-derived enzyme, after acute colitis induction in mice: Decrease of intestinal inflammation associated with a down regulation of Th1/Th17 responses.
P28GST, a 28Kd glutathione S-transferase enzymatic protein derived from a schistosome helminth prevents experimental colitis when administered subcutaneously in the presence of adjuvant by decreasing pro-inflammatory Th1/Th17 response. Given the antioxidant properties of P28GST, we evaluated its anti-inflammatory potential when administered locally after colitis induction in the absence of adjuvant.. Colitis was induced in BALB/c mice by rectal administration of TNBS, followed by two intraperitoneal injections of P28GST at day 1 and day 2. Mice were sacrificed 48h after TNBS administration and evaluated for macroscopic and histological scores, myeloperoxidase (MPO) quantification and cytokine messenger RNA expression in the colonic tissues.. Both clinical and histological scores significantly decreased in mice treated with P28GST at 5 or 50μg/kg when compared to vehicle- treated mice. A significant reduction of MPO was detected in colonic tissues from P28GST-treated mice, similarly to mice treated with methylprednisolone as the reference treatment. Pro-inflammatory cytokines TNF, IL-1β, and IL-6, mRNA as well as serum levels were down-regulated in mice colonic tissues treated with P28GST at 5 or 50μg/kg. In addition, a significant decrease of mRNA expression levels of T-bet, and ROR-γ, respective markers of Th1 and Th17 cells was observed. Whereas no significant effect was detected on Gata3 mRNA, a marker of Th2 cells, the Arg/iNOS mRNA levels significantly increased in P28GST-treated mice, suggesting the induction of M2 macrophages.. These findings provide evidence that P28GST injected locally after colitis induction induces a potent decrease of colitis inflammation in mice, associated to downregulation of Th1/Th17 response, and induction of anti-inflammatory alternatively activated macrophages. Topics: Animals; Biomarkers; Colitis; Cytokines; Disease Models, Animal; Female; Glutathione Transferase; Helminth Proteins; Inflammation Mediators; Macrophages; Mice; Peroxidase; Severity of Illness Index; Th1 Cells; Th17 Cells | 2018 |
High activity of the endogenous opioid system and acute but not chronic stress influence experimental colitis development in mice.
Exposition to environmental factors is one of the major underlying causes in inflammatory bowel diseases (IBD), with several endogenous systems involved. Our aim was to characterize the impact of stress on the colitis development in relation to the endogenous opioid system (EOS) activity in mice. A unique mouse model of high and low activity of EOS (namely high (HA)/low (LA) stress-induced analgesia) was employed. Mice were bred using bidirectional selection and classified as HA or LA line based on the measurement of analgesia. Colitis was induced by instillation of trinitrobenzenesulfonic acid in 30% EtOH/0.9% NaCl. After 4 days, the macroscopic score was assessed and samples for molecular and histological studies were collected. To evaluate the influence of stress on colitis development, chronic mild stress (exposure to stress stimuli for 2 and 5 weeks) and acute stress (short restraint over 3 days) were applied before colitis induction. We observed a difference in the colitis development between non-stressed HA and LA mice, as indicated by macroscopic and ulcer scores. Acute stress improved colitis in HA mice but did not change the inflammation score in LA line as compared to respective non-stressed mice. Chronic mild stress had no influence on colitis in either of mouse lines. Our study supports the hypothesis that the activity of EOS may be crucial in IBD development. We also evidence that acute, but not chronic stress influenced IBD exacerbation, depending on EOS function. Topics: Analgesia; Animals; Colitis; Disease Models, Animal; Male; Mice; Narcotic Antagonists; Peroxidase; Stress, Psychological; Trinitrobenzenesulfonic Acid | 2018 |
The effect of menthol on acute experimental colitis in rats.
Menthol is an aromatic compound with high antiinflammatory activity. The purpose of the current research is to investigate the effectiveness of menthol on acetic acid induced acute colitis in rats. Animals were injected with menthol (20 and 50 and 80mg/kg, i.p.) 24h prior to induction of colitis for 3 consecutive days. Menthol at medium and higher doses similar to dexamethasone as a reference drug significantly reduced body weight loss, macroscopic damage score, ulcer area, colon weight, colon length and improved hematocrit in rats with colitis. The histopathological examination also confirmed anti-colitic effects of menthol. Menthol also reduced significantly the colonic levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6) and myeloperoxidase (MPO) activity in inflamed colons. Thus, the findings of the current study provide evidence that menthol may be beneficial in patients suffering from acute ulcerative colitis. Topics: Acute Disease; Animals; Body Weight; Colitis; Colon; Cytokines; Disease Models, Animal; Hematocrit; Male; Menthol; Peroxidase; Rats; Rats, Wistar | 2017 |
Rosmarinic acid suppresses colonic inflammation in dextran sulphate sodium (DSS)-induced mice via dual inhibition of NF-κB and STAT3 activation.
Ulcerative colitis (UC), a type of inflammatory bowel disease (IBD), is a chronic inflammatory disorder of the colon. Although UC is generally treated with anti-inflammatory drugs or immunosuppressants, most of these treatments often prove to be inadequate. Rosmarinic acid (RA) is a phenolic ester included in various medicinal herbs such as Salvia miltiorrhiz and Perilla frutescens. Although RA has many biological and pharmacological activities, the anti-inflammatory effect of RA in colonic tissue remains unclear. In this study, we investigated the anti-inflammatory effects and underlying molecular mechanism of RA in mice with dextran sulphate sodium (DSS)-induced colitis. In the DSS-induced colitis model, RA significantly reduced the severity of colitis, as assessed by disease activity index (DAI) scores, colonic damage, and colon length. In addition, RA resulted in the reduction of the inflammatory-related cytokines, such as IL-6, IL-1β, and IL-22, and protein levels of COX-2 and iNOS in mice with DSS-induced colitis. Furthermore, RA effectively and pleiotropically inhibited nuclear factor-kappa B and signal transducer and activator of transcription 3 activation, and subsequently reduced the activity of pro-survival genes that depend on these transcription factors. These results demonstrate that RA has an ameliorative effect on colonic inflammation and thus a potential therapeutic role in colitis. Topics: Animals; Cinnamates; Colitis; Colon; Cyclooxygenase 2; Cytokines; Depsides; Dextran Sulfate; Disease Models, Animal; Disease Progression; Gene Expression Regulation; Inflammation; Inflammation Mediators; Male; Mice, Inbred ICR; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Rosmarinic Acid; Spleen; STAT3 Transcription Factor | 2017 |
Protective effects of tranilast on experimental colitis in rats.
The present study aimed to verify the efficacy of tranilast (TL) for treating inflammatory bowel disease (IBD) with the use of an experimental colitis model. The experimental colitis model was prepared by intrarectal instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS; 40mg/kg) dissolved in water containing 25% ethanol. The pharmacological effects of TL after repeated oral administration were evaluated by biomarker and histological analyses, and the pharmacokinetic behavior of TL was also examined after single oral administration. The intrarectal instillation of TNBS solution caused colitis, as evidenced by ca. 2.2-, 5-, and 3-fold increases in myeloperoxidase (MPO) activity, infiltrated cell numbers, and the thickness of the submucosa in the colon, respectively. However, orally-taken TL (10mg/kg, twice a day for 9days) led to a 92% reduction in the increase of the MPO level by TNBS enema, and cellular infiltration and thickened submucosa in the experimental colitis model tended to also be suppressed by repeated oral administration of TL. The oral bioavailability of TL in TNBS-treated rats was calculated to be as low as ca. 6.5%, and the poor oral absorption of TL may be a limitation of the treatment for IBD. TL could attenuate TNBS-induced colitis on the basis of the obtained results, and the anti-inflammatory effects would have clinical relevance to the therapeutic outcomes of TL in IBD patients. Although further improvement in the oral bioavailability of TL might be required for better pharmacological outcomes, TL would be an efficacious agent for treating IBD. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Disease Models, Animal; Inflammatory Bowel Diseases; Intestinal Mucosa; Male; ortho-Aminobenzoates; Peroxidase; Protective Agents; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2017 |
Mechanism of down regulation of Na-H exchanger-2 in experimental colitis.
The Na-H exchanger [NHE] performs an electroneutral uptake of NaCl and water from the lumen of the gastrointestinal tract. There are several distinct NHE isoforms, some of which show an altered expression in the inflammatory bowel diseases (IBD). In this study, we examined a role of NHE-2 in experimental colitis.. Colitis was induced in male Sprague-Dawley rats by intra-rectal administration of trinitrobenzenesulphonic acid (TNBS). On day 6 post-TNBS, the animals were sacrificed, colonic and ileal segments were taken out, cleaned with phosphate buffered saline and used in this study.. There was a significant decrease in the level of NHE-2 protein as measured by ECL western blot analysis and confocal immunofluorescence microscopy. The levels of NHE-2 mRNA and heteronuclear RNA measured by an end-point RT-PCR and a real time PCR were also decreased significantly in the inflamed colon. However, there was no change in the level of NHE-2 protein in response to in vitro TNF-α treatment of uninflamed rat colonic segment. These changes were selective and localized to the colon as actin, an internal control, remained unchanged. Confocal immunofluorescence microscopy revealed co-localization of NHE-2 and NHE-3 in the brush borders of colonic epithelial cells. Inflamed colon showed a significant increase in myeloperoxidase activity and colon hypertrophy. In addition, there was a significant decrease in body weight and goblet cells' mucin staining in the TNBS treated colon. These changes were not conspicuous in the non-inflamed ileum.. These findings demonstrate suppression of NHE-2 expression on the brush borders in the colonic epithelial cells which is regulated transcriptionally. However a role of TNF-α in the regulation of NHE-2 is discounted in the present model of colitis. This decrease in the NHE-2 expression will lead to a loss of electrolyte and water uptake thus contributing to the symptoms associated with IBD. Topics: Animals; Blotting, Western; Body Weight; Colitis; Colon; Down-Regulation; Electrophoresis, Agar Gel; Goblet Cells; Hypertrophy; Ileum; Male; Microscopy, Fluorescence; Peroxidase; Rats, Sprague-Dawley; Real-Time Polymerase Chain Reaction; RNA, Messenger; Sodium-Hydrogen Exchangers; Staining and Labeling; Tumor Necrosis Factor-alpha | 2017 |
Anti-inflammatory effects and mechanisms of vagal nerve stimulation combined with electroacupuncture in a rodent model of TNBS-induced colitis.
Topics: Animals; Colitis; Cytokines; Electroacupuncture; Gene Expression Regulation; Inflammation; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Time Factors; Trinitrobenzenesulfonic Acid; Vagus Nerve Stimulation | 2017 |
Methionine restriction on oxidative stress and immune response in dss-induced colitis mice.
A strong correlation exists between inflammatory bowel disease (IBD) and oxidative stress involving alterations of several key signaling pathways. It is known that methionine promotes reactive oxygen species (ROS) production; we therefore hypothesize that a methionine restriction diet would reduce ROS production, inflammatory responses, and the course of IBD. We generated a murine colitis model by dextran sodium sulfate (DSS) treatment and tested the effects of the methionine restriction diet. Forty-eight mice were randomly divided into four groups of equal size, which included a control (CON) group, an MR (methionine restriction diet) group, a DSS treated group and an MR-DSS treated group. Mice in the first two groups had unrestricted access to water for one week. Mice in the two DSS-treated groups had unrestricted access to 5% DSS solution supplied in the drinking water for the same period. Mice in the CON and DSS groups were given a basal diet, whereas mice in the MR-DSS and MR groups were fed a 0.14% MR diet. We found that DSS reduced daily weight gain, suppressed antioxidant enzyme expression, increased histopathology scores and activated NF-κB and nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/Keap1) signaling. We also showed that the MR diet upregulated catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities, decreased myeloperoxidase (MPO), TNF-α and IL-1β, and reversed activation of the NF-κB signaling pathway in MR-DSS mice. Taken together, our results imply that the MR diet may be considered as an adjuvant in IBD therapeutics. Topics: Animals; Biomarkers; Catalase; Colitis; Dextran Sulfate; Disease Models, Animal; Immunity; Inflammatory Bowel Diseases; Intestinal Mucosa; Male; Methionine; Mice; NF-kappa B; Oxidative Stress; Peroxidase; Reactive Oxygen Species; Signal Transduction; Superoxide Dismutase | 2017 |
Prophylactic and therapeutic effect of Punica granatum in trinitrobenzene sulfonic acid induced inflammation in rats.
Pomegranate (Punica granatum L., Punicaceae) contains varieties of antioxidants and phytochemicals; there are evidences that phytochemicals and antioxidants play a vital role in reducing inflammation. Hence this investigation was planned to assess the outcome of Punica granatum on trinitrobenzene sulfonic acid provoked colitis in rats at 2, 5 and 8ml/kg of the body weight. The effect of P. granatum was assessed in two group i.e. prophylaxis as pre-colitis and therapeutic as post-colitis. After completion of dosing in both the groups, macroscopic and histological examination of colon was carried out along with estimation of serum myeloperoxidase, glutathione, alkaline phosphate, fibrinogen and C-reactive protein. In prophylactic procedure P. granatum revealed significant (P<0.05) changes in biochemical markers of inflammation at 5 and 8ml/kg doses. However in therapeutic procedure significant change was observed only at 8ml/kg. Thus results of the present study suggest that P. granatum have a role in prevention as well as treatment of inflammation. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Biomarkers; Carrier Proteins; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Fibrinogen; Gastrointestinal Agents; Glutathione; Inflammation Mediators; Lythraceae; Male; Peroxidase; Phytotherapy; Plant Extracts; Plants, Medicinal; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2017 |
Study of intestinal anti-inflammatory activity of Phoenix loureiroi Kunth (Arecaceae) fruit.
Phoenix loureiroi Kunth belongs to the family Arecaceae, the fruits are widely consumed by Kurumba and Irula tribes of Tamil Nadu (India) and also used to cure intestinal related diseases in folklore medicine. Therefore, in vivo animal studies were evaluated to confirm the prevention of inflammatory bowel disease (IBD) with the treatment of this plant fruits. The IBD was studied in Wistar albino rats by indomethacin (s.c.), acetic acid (i.c.) and dextran sulfate sodium (DSS) induced models. The diseases parameters such as macroscopic, microscopic features, serum biomarkers levels, haematological profile, biochemical and antioxidant levels were determined. The fruit extract (50, 100 and 200mg/kg) treated enterocolitis rats significantly retain their body weight, organ weight, stool consistency, macroscopic score, histology, haematological parameters, antioxidative enzyme levels and also reduce the serum marker levels and myeloperoxidase (MPO) activity compared to prednisolone (2mg/kg) and sulfasalazine (50mg/kg) drugs. In conclusion, regular consumption of P. loureiroi fruit may prevent IBD and strongly support the folklore use of fruit in the treatment of intestinal ailments. Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Arecaceae; Colitis; Fruit; India; Inflammatory Bowel Diseases; Intestinal Mucosa; Intestines; Male; Mice; Peroxidase; Plant Extracts; Prednisolone; Rats; Rats, Wistar; Sulfasalazine | 2017 |
G protein-coupled receptor 35 contributes to mucosal repair in mice via migration of colonic epithelial cells.
G protein-coupled receptor 35 (GPR35), a receptor for lysophosphatidic acid, is highly expressed in the gastrointestinal tract. Recently, GPR35 has been implicated in the onset of inflammatory bowel disease (IBD), but its role in physiological and pathological processes in the colon remains undefined. In this study, we investigated the contribution of GPR35-mediated signalling to mucosal repair of colonic epithelium in IBD. GPR35 function was examined in a wound healing model, using young adult mouse colon epithelium (YAMC) cells, and in a dextran sulphate sodium (DSS)-induced mouse model of colitis. Cell proliferation, mRNA expression, extracellular signal-regulated kinase (ERK) activation, and protein localization were determined by MTT assay, quantitative RT-PCR, western blotting, and immunohistochemistry, respectively. GPR35 agonists (YE120, zaprinast, and pamoic acid) promoted wound repair in a concentration-dependent manner independently of cell proliferation, whereas a specific GPR35 antagonist CID2745687, forskolin, and pertussis toxin reversed the YE120-induced effect. YE120 increased the mRNA expression of fibronectin and its receptor integrin α5, and ERK1/2 phosphorylation, but these responses were attenuated by CID2745687 and forskolin. Furthermore, the severity of DSS-induced colitis was significantly reduced by daily injections of pamoic acid via upregulation of fibronectin and integrin α5 in the colonic epithelium. GPR35 signalling promotes mucosal repair by inducing fibronectin and integrin α5 expression, coupling to Gi protein, and activating ERK1/2 in colonic epithelial cells. These findings define GPR35 as a candidate therapeutic target in IBD. Topics: Animals; Cell Line; Cell Movement; Colitis; Colon; Cytokines; Dextran Sulfate; Epithelial Cells; Extracellular Signal-Regulated MAP Kinases; Fibronectins; Furans; Integrins; Intestinal Mucosa; Male; Mice, Inbred C57BL; Naphthols; Nitriles; Peroxidase; Purinones; Rats; Receptors, G-Protein-Coupled; RNA, Messenger; Wound Healing | 2017 |
The Mixture of Anemarrhena asphodeloides and Coptis chinensis Attenuates High-Fat Diet-Induced Colitis in Mice.
Anemarrhena asphodeloides (AA, family Liliaceae) inhibits macrophage activation by inhibiting IRAK1 phosphorylation and helper T (Th)17 differentiation. Coptis chinensis (CC, family Ranunculaceae), which inhibits macrophage activation by inhibiting the binding of lipopolysaccharide (LPS) on toll-like receptor 4 and inducing regulatory T (Treg) cell differentiation. The mixture of AA and CC (AC-mix) synergistically attenuates 2,4,6-trinitrobenzenesulfonic acid or dextran sulfate sodium-induced colitis in mice by inhibiting NF-[Formula: see text]B activation and regulating Th17/Treg balance. In the present study, we examined the effect of AC-mix on high-fat diet (HFD)-induced colitis in mice, which induced NF-[Formula: see text]B activation and disturbed Th17/Treg balance. Long-term feeding of HFD in mice caused colitis, including increased macroscopic score and myeloperoxidase activity. Oral administration of AC-mix (20[Formula: see text]mg/kg) suppressed HFD-induced myeloperoxidase activity by 68% ([Formula: see text]). Furthermore, treatment with the AC-mix (20[Formula: see text]mg/kg) inhibited HFD-induced activation of NF-[Formula: see text]B and expression of cyclooxygenase-2, inducible NO synthase, interleukin (IL)-17, and tumor necrosis factor-alpha but increased HFD- suppressed expression of IL-10. AC-mix suppressed HFD-induced differentiation into Th17 cells by 46% ([Formula: see text]) and increased HFD-induced differentiation into regulatory T cells 2.2-fold ([Formula: see text]). AC-mix also suppressed the HFD-induced Proteobacteria/Bacteroidetes ratio on the gut microbiota by 48% ([Formula: see text]). These findings suggest that AC-mix can ameliorate HFD-induced colitis by regulating innate and adaptive immunities and correcting the disturbance of gut microbiota. Topics: Adaptive Immunity; Administration, Oral; Anemarrhena; Animals; Cell Differentiation; Colitis; Coptis; Diet, High-Fat; Drug Combinations; Drug Synergism; Gastrointestinal Microbiome; Immunity, Innate; Macrophage Activation; Male; Mice, Inbred C57BL; NF-kappa B; Peroxidase; Phytotherapy; Plant Extracts; T-Lymphocytes, Regulatory | 2017 |
Extract from mango mistletoes Dendrophthoe pentandra ameliorates TNBS-induced colitis by regulating CD4+ T cells in mesenteric lymph nodes.
Mango mistletoes Dendrophthoe pentandra (MMDP) extract has attracted interest due to its pharmacological properties, including gastro protective effects. The aim of this study was to investigate whether MMDP extract could increase Foxp3 regulatory T cells and inhibits development of Th17 cells.. Colitis was induced in Balb/c mice by rectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS). The mice were randomly divided into five groups comprising group1 receiving vehicle (the negative control), group 2-5 receiving TNBS, group 3-5 orally receiving either MMDP extract 150, 300 and 600 mg/kgBW for 7 days after TNBS administration. On day 8 of the experiment, the colon tissues were removed for histological examination, cytokine and myeloperoxidase (MPO) measurement. T-cells sub-population in mesenteric lymph nodes were analyzed by flow cytometer.. MMDP extract potently suppressed colon shortening and MPO in mice with TNBS-induced colitis. Administration of the extract significantly decreased the severity of TNBS-induced colitis in a dose-dependent manner. The extract significantly attenuated the loss of body weight (p < 0.05). These effects were associated with a remarkable amelioration of the disruption of the colonic architecture, significant reduction of the colonic MPO (p < 0.05). The extract lowered the levels of Th17-associated cytokines but increased the production of Treg-associated cytokines in mesenteric lymph node cells.. Our results suggest that MMDP has the therapeutic potential to ameliorate TNBS-induced colitis symptoms revealed by histological change and inhibit IL-17 production. Topics: Animals; CD4-Positive T-Lymphocytes; Colitis; Colon; Disease Models, Animal; Female; Interleukin-10; Interleukin-17; Loranthaceae; Lymph Nodes; Mice, Inbred BALB C; Peroxidase; Plant Extracts; Th17 Cells; Trinitrobenzenesulfonic Acid | 2017 |
Anti-inflammatory effect of Euphorbia supina extract in dextran sulfate sodium-induced colitis mice.
The aim of this study is to examine the anti-inflammatory effect of Euphorbia supina (ES) ethanol extract in dextran sulfate sodium (DSS)-induced experimental colitis model. ES was per orally administered at different doses of 4 or 20 mg/kg body weight with 5% DSS in drinking water for 7 days. Twenty mg/kg of ES administration regulated body weight decrease, recovered colon length shortening, and increased disease activity index score and myeloperoxidase level in DSS-induced colitis. Histological features showed that 20 mg/kg of ES administration suppressed edema, mucosal damage, and the loss of crypts induced by DSS. Furthermore, ES suppressed the expressions of COX-2, iNOS, NF-kB, IkBα, pIkBα in colon tissue. These findings demonstrated a possible effect of amelioration of ulcerative colitis and could be clinically applied. Topics: Animals; Anti-Inflammatory Agents; Body Weight; Colitis; Colon; Cyclooxygenase 2; Dextran Sulfate; Ethanol; Euphorbia; Gene Expression Regulation, Enzymologic; Male; Mice; Mice, Inbred BALB C; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Plant Extracts; RAW 264.7 Cells; Signal Transduction; Tumor Necrosis Factor-alpha | 2017 |
Maillard reaction products from highly heated food prevent mast cell number increase and inflammation in a mouse model of colitis.
Links between food and inflammatory bowel diseases (IBDs) are often suggested, but the role of food processing has not been extensively studied. Heat treatment is known to cause the loss of nutrients and the appearance of neoformed compounds such as Maillard reaction products. Their involvement in gut inflammation is equivocal, as some may have proinflammatory effects, whereas other seem to be protective. As IBDs are associated with the recruitment of immune cells, including mast cells, we raised the hypothesis that dietary Maillard reaction products generated through heat treatment of food may limit the colitic response and its associated recruitment of mast cells. An experimental model of colitis was used in mice submitted to mildly and highly heated rodent food. Adult male mice were divided in 3 groups and received nonheated, mildly heated, or highly heated chow during 21 days. In the last week of the study, each group was split into 2 subgroups, submitted or not (controls) to dextran sulfate sodium (DSS) colitis. Weight variations, macroscopic lesions, colonic myeloperoxidase activity, and mucosal mast cell number were evaluated at the end of the experiment. Only highly heated chow significantly prevented DSS-induced weight loss, myeloperoxidase activity, and mast cell number increase in the colonic mucosa of DSS-colitic mice. We suggest that Maillard reaction products from highly heated food may limit the occurrence of inflammatory phases in IBD patients. Topics: Animals; Cell Count; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Glycation End Products, Advanced; Inflammation; Inflammatory Bowel Diseases; Intestinal Mucosa; Male; Mast Cells; Mice; Mice, Inbred BALB C; Peroxidase; Weight Loss | 2017 |
Anti-inflammatory effects of enemas containing an oily extract of curcumin in an experimental model of diversion colitis.
Curcumin has powerful anti-inflammatory and antioxidant effects and it has been used for treatment of distal ulcerative colitis. The therapeutic effects of curcumin have not yet been evaluated in diversion colitis. The aim of the present study was to evaluate the anti-inflammatory effects of curcumin on colonic mucosa devoid of a faecal stream. Thirty-six rats were subjected to a proximal colostomy and distal colonic fistulation. They were divided into two groups, which were sacrificed two or four weeks after the intervention. Each group was divided into three subgroups treated with the daily application of enemas containing saline or an oily extract of curcumin at 50 mg/kg/day or 200 mg/kg/day. Colitis was diagnosed by histological analysis. Inflammatory grades were assessed using a previously validated scoring system. The infiltration of neutrophils was evaluated based on the tissue expression of myeloperoxidase (MPO), as determined by immunohistochemistry, and a computer-assisted image analysis program. The Mann-Whitney test was used to compare inflammation grades and myeloperoxidase levels among groups, and ANOVA was used to verify the variance over time, with the level of significance set at 5% (p<0.05) for both tests. Enemas containing curcumin improved the inflammation of the mucosa without a faecal stream and reduced the tissue contents of MPO. MPO tissue levels did not vary with time or between the concentrations of curcumin used. Enemas with curcumin improved the inflammation of the colonic mucosa, reduced the inflammatory grade and decreased the tissue content of MPO in colon segments without a faecal stream. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Curcumin; Disease Models, Animal; Enema; Intestinal Mucosa; Male; Oxidative Stress; Peroxidase; Rats; Rats, Wistar | 2017 |
Anti-Inflammatory Effect of Erythropoietin in the TNBS-induced Colitis.
Erythropoietin is a potent stimulator of erythroid progenitor cells, which is able to inhibit NF-kB activation, due to its pleiotropic properties, thus promoting an anti-inflammatory effect. As inflammatory bowel disease is a chronic disease with reduced quality of life, and the current pharmacotherapy only induces or maintains the patient in remission, there is a crucial need of new pharmacological approaches. The main objective of this study was to evaluate the effect of erythropoietin in the TNBS-induced colitis model in mice with a normal intestinal flora. Mice with TNBS-induced colitis were treated with a daily dose of erythropoietin at 500 IU/kg bw/day and 1000 IU/Kg bw/day IP during 4 days. As to clinical symptoms/signs, erythropoietin attenuated the decreased body-weight and reduced diarrhoea and oedema of the anus registered in the non-treated mice group in a dose-dependent manner. The anti-inflammatory properties of erythropoietin in the TNBS-induced colitis were confirmed by suppression of pro-inflammatory mediators, such as TNF-α, IL-1β and MPO, as well as a significant increase in the anti-inflammatory cytokine, IL-10, was promoted. These treated mice also presented a reduction in haemoglobin faecal and ALP, suggesting a beneficial effect of erythropoietin in the haemorrhagic focus and destruction of the enterocyte associated with the colon injury induced by TNBS, respectively. The histopathological score was reduced after treatment with erythropoietin, decreasing the severity and extension of the colitis. Furthermore, renal and hepatic biomarkers, as well as haematocrit concentration, remained stabilized after treatment. In conclusion, erythropoietin reduces the inflammatory response associated with TNBS-induced colitis in mice. Topics: Animals; Anti-Inflammatory Agents; Biomarkers; Colitis; Colon; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Epoetin Alfa; Inflammation Mediators; Male; Mice; Peroxidase; Severity of Illness Index; Time Factors; Trinitrobenzenesulfonic Acid | 2017 |
Cell-specific Activation of the Nrf2 Antioxidant Pathway Increases Mucosal Inflammation in Acute but Not in Chronic Colitis.
The transcription factor Nrf2 is a major modulator of the cellular antioxidant response. Oxidative burst of infiltrating macrophages leads to a massive production of reactive oxygen species in inflamed tissue of inflammatory bowel disease patients. This oxidative burst contributes to tissue destruction and epithelial permeability, but it is also an essential part of the antibacterial defence. We therefore investigated the impact of the Nrf2 orchestrated antioxidant response in both acute and chronic intestinal inflammation.. To study the role of Nrf2 overexpression in mucosal inflammation, we used transgenic mice conditionally expressing a constitutively active form of Nrf2 [caNrf2] either in epithelial cells or in the myeloid cell lineage. Acute colitis was induced by dextran sulphate sodium [DSS] in transgenic and control animals, and changes in gene expression were evaluated by genome-wide expression studies. Long-term effects of Nrf2 activation were studied in mice with an IL-10-/- background.. Expression of caNrf2 either in epithelial cells or myeloid cells resulted in aggravation of DSS-induced acute colitis. Aggravation of inflammation by caNrf2 was not observed in the IL-10-/- model of spontaneous chronic colitis, where even a trend towards reduced prolapse rate was observed.. Our findings show that a well-balanced redox homeostasis is as important in epithelial cells as in myeloid cells during induction of colitis. Aggravation of acute DSS colitis in response to constitutive Nrf2 expression emphasises the importance of tight regulation of Nrf2 during the onset of intestinal inflammation. Topics: Acute Disease; Animals; Chronic Disease; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Female; Interleukin-10; Intestinal Mucosa; Macrophages; Male; Mice; Mice, Transgenic; Myeloid Cells; NF-E2-Related Factor 2; Peroxidase; Respiratory Burst | 2017 |
NOX1/NADPH Oxidase Expressed in Colonic Macrophages Contributes to the Pathogenesis of Colonic Inflammation in Trinitrobenzene Sulfonic Acid-Induced Murine Colitis.
NOX1/NADPH oxidase, a nonphagocytic isoform of reactive oxygen species-producing enzymes, is highly expressed in the colon, but the physiologic and pathophysiologic roles of this isoform are not fully understood. The present study investigated the role of NOX1 in the development of colonic inflammation in a trinitrobenzene sulfonic acid (TNBS)-induced murine colitis model. Intrarectal injection of TNBS caused severe colitis accompanied by body weight loss, diarrhea, and increased myeloperoxidase (MPO) activity in wild-type (WT) mice. In contrast, the severity of colitis was significantly attenuated in NOX1-deficient (NOX1KO) mice (the inhibitions of macroscopic damage score, body weight loss, diarrhea score, and MPO activity were 73.1%, 36.8%, 83.3%, and 98.4%, respectively). TNBS-induced upregulation of inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-1β), chemokines (CXCL1 and CXLC2), and inducible nitric oxide synthase (iNOS) was also significantly less in NOX1KO than in WT mice (the inhibitions were 100.8%, 89.0%, 63.5%, 96.7%, and 97.1%, respectively). Expression of NOX1 mRNA was detected not only in the lamina propria but also in peritoneal macrophages isolated from WT mice. Increased expression of TNF-α, IL-1β, and iNOS in peritoneal macrophages exposed to lipopolysaccharide was significantly attenuated in macrophages isolated from NOX1KO mice (68.1%, 67.0%, and 79.3% inhibition, respectively). These findings suggest that NOX1/NADPH oxidase plays an important role in the pathogenesis of TNBS-induced colonic inflammation via upregulation of inflammatory cytokines, chemokines, and iNOS. NOX1 in colonic macrophages may become a potential target in pharmacologic intervention for inflammatory bowel disease. Topics: Animals; Body Weight; Colitis; Colon; Diarrhea; Gene Expression Regulation, Enzymologic; Gene Knockout Techniques; Lipopolysaccharides; Macrophages, Peritoneal; Male; Mice; NADH, NADPH Oxidoreductases; NADPH Oxidase 1; Peroxidase; RAW 264.7 Cells; Reactive Oxygen Species; RNA, Messenger; Trinitrobenzenesulfonic Acid; Up-Regulation | 2017 |
An HDAC6 Inhibitor Confers Protection and Selectively Inhibits B-Cell Infiltration in DSS-Induced Colitis in Mice.
Small molecule histone deacetylase (HDAC) inhibitors with anti-inflammatory activity may be candidates for targeting intestinal inflammatory pathways in inflammatory bowel disease (IBD). This study investigated whether treatment with a potent HDAC6 inhibitor, BML-281, could protect against colonic inflammation and prevent inflammatory cell infiltration into the colon to drive disease pathology in a mouse model of acute dextran sodium sulfate (DSS) colitis. Control and acute DSS-colitis mice were treated with BML-281 (1 mg/kg per day s.c. and 10 mg/kg per day s.c.) for 8 days. Changes in disease pathology, colonic structure, function, alterations in inflammatory milieu, together with colonic inflammatory cell flux, were assessed by weight loss and disease activity index in vivo and by flow cytometry, gene expression, and histology ex vivo. Anti-inflammatory responses of BML-281 on human polymorphonuclear leukocytes were assessed in vitro. Administration of BML-281 to DSS-treated mice attenuated colitis, weight loss, and disease pathology, including changes in colon structure and function, by eliciting broad-spectrum anti-inflammatory effects and preventing infiltration and activation of key immune cells in the lamina propria of the intestinal epithelium. Among different immune cells, BML-281 particularly suppressed the infiltration of CD19 Topics: Animals; B-Lymphocytes; Colitis; Colon; Cytokines; Dextran Sulfate; Diarrhea; Female; Hemorrhage; Histone Deacetylase 6; Histone Deacetylase Inhibitors; Histone Deacetylases; Hydroxamic Acids; Intestinal Mucosa; Isoxazoles; Lymphocytes; Mice; Mice, Inbred C57BL; Mucins; Myeloid Cells; Neutrophil Activation; Peroxidase | 2017 |
Antioxidant properties of mesenchymal stem cells against oxidative stress in a murine model of colitis.
To investigate the effects of oxidative stress injury in dextran sulfate sodium (DSS)-induced colitis in mice treated with mesenchymal stem cells (MSC).. Mice exposed to oral administration of 2% DSS over 7 days presented a high disease activity index and an intense colonic inflammation. Systemic infusion of MSC protected from severe colitis, reducing weight loss and diarrhea while lowering the infiltration of inflammatory cells. Moreover, toxic colitis injury increased oxidative stress. Administration of DSS decreased reduced glutathione (GSH) and superoxide dismutase (SOD) activity, and increased thiobarbituric acid-reactive substances levels in the colon. No alteration was found in catalase (CAT) and glutathione peroxidase (GPx) activity. Otherwise, MSC transplantation was able to prevent the decrease of GSH levels and SOD activity suggestive of an antioxidant property of MSC.. The oxidative stress is a pathomechanism underlying the pathophysiology of colitis and MSC play an important role in preventing the impairment of antioxidants defenses in inflamed colon. Topics: Animals; Antioxidants; Catalase; Colitis; Colon; Dextran Sulfate; Glutathione; Lipid Peroxidation; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Oxidative Stress; Peroxidase; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances | 2017 |
Monitoring of Chemically Induced Colitis.
Inflammation is a common symptom of inflammatory bowel disease (IBD). Actually, many experimental models of colitis exist and try to mimic the human situation in order to understand the pathogenesis of Crohn's disease and ulcerative colitis. These experimental models of inflammation can be characterized by specific parameters, which illustrate the proceeding inflammatory process. By use of these models potentially new reagents for improved therapeutic approaches can be analyzed. Here, we describe the TNBS-mediated colitis model and specify different parameters for the detailed characterization of the inflammatory process in experimental colitis models. Topics: Animals; Antigens, CD; Antigens, Differentiation; Biomarkers; Body Weight; Colitis; Colonoscopy; Cytokines; Disease Models, Animal; Gene Expression; Humans; Immunity, Mucosal; Immunohistochemistry; Mice; Mucous Membrane; Peroxidase; Severity of Illness Index; Trinitrobenzenesulfonic Acid | 2017 |
Dietary tryptophan alleviates dextran sodium sulfate-induced colitis through aryl hydrocarbon receptor in mice.
Ulcerative colitis is the typical progression of chronic inflammatory bowel disease. Amino acids, particularly tryptophan, have been reported to exert a protective effect against colitis induced by dextran sodium sulfate (DSS), but the precise underlying mechanisms remain incompletely clarified. Tryptophan metabolites are recognized to function as endogenous ligands for aryl hydrocarbon receptor (Ahr), which is a critical regulator of inflammation and immunity. Thus, we conducted this study to investigate whether dietary tryptophan supplementation protects against DSS-induced colitis by acting through Ahr. Female wild-type (WT) and Ahr-deficient (knockout; KO) mice (10-12 weeks old) were divided into four groups and fed either a control or 0.5% tryptophan diet. The tryptophan diet ameliorated DSS-induced colitis symptoms and severity in WT mice but not in KO mice, and the diet reduced the mRNA expression of Il-6, Tnfα, Il-1β and the chemokines Ccl2, Cxcl1 and Cxcl2 in the WT groups. Furthermore, Il-22 and Stat3 mRNA expression in the colon was elevated in WT mice fed with the tryptophan diet, which mainly protected epithelial layer integrity, and Ahr also modulated immune homeostasis by regulating Foxp3 and Il-17 mRNA expression. These data suggest that tryptophan-containing diet might ameliorate DSS-induced acute colitis and regulate epithelial homeostasis through Ahr. Thus, tryptophan could serve as a promising preventive agent in the treatment of ulcerative colitis. Topics: Animals; Chemokines; Colitis; Colon; Cytokines; Dextran Sulfate; Dietary Supplements; Female; Interleukin-22; Interleukins; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Receptors, Aryl Hydrocarbon; STAT3 Transcription Factor; Tryptophan | 2017 |
Astragalus polysaccharides protect against dextran sulfate sodium-induced colitis by inhibiting NF-κВ activation.
Astragalus polysaccharide (APS) is a bioactive extract of Astragalus membranaceus (AM), which possess a wide range of medicinal benefits, including anti-inflammatory, anti-oxidative, anti-tumor and anti-diabetic effects. The present work evaluated the therapeutic effect of APS and its potential mechanisms in a mouse model of dextran sulfate sodium (DSS)-induced colitis. The APS treatment led to significant improvements in colitis disease activity index (DAI) and histological scores, as well as significantly increased weight and colon length in mice as compared to the control group. Mechanically, reduced NF-κВ DNA phosphorylation activity and downregulated TNF-α, IL-1β, IL-6, IL-17 expressions and myeloperoxidase (MPO) activity were associated with improvement in colitis observed in APS-treated mice. These findings suggest that APS may represent a natural therapeutic approach for treating inflammatory bowel disease, such as ulcerative colitis. Topics: Animals; Anti-Inflammatory Agents; Astragalus Plant; Colitis; Dextran Sulfate; Disease Models, Animal; Humans; Interleukin-17; Interleukin-6; Mice; NF-kappa B; Peroxidase; Polysaccharides; Protective Agents; Signal Transduction; Tumor Necrosis Factor-alpha | 2017 |
Prdx6 Deficiency Ameliorates DSS Colitis: Relevance of Compensatory Antioxidant Mechanisms.
An imbalance between cellular antioxidant defence system[s] and reactive oxygen species [ROS]-driven oxidative stress has been implicated in the pathogenesis of inflammatory bowel disease. Peroxiredoxin [PRDX] 6 contributes to an appropriate redox balance by clearing ROS and reducing peroxidized membrane phospholipids. We here studied the role of PRDX6 in acute and chronic dextran sodium sulphate [DSS]-induced colitis.. To investigate the impact of PRDX6 on intestinal inflammation, we used wild type [WT], Prdx6 knock-out mice [Prdx6-/-] and transgenic mice [Prdx6tg/tg], overexpressing Prdx6. Acute and chronic colitis was induced by DSS in WT, Prdx6-/- and Prdx6tg/tg mice. Colitis was evaluated by endoscopy, colon length, histopathological assessment and myeloperoxidase [MPO] activity. Changes in mRNA and protein expression of pro-inflammatory cytokines and antioxidant enzymes were evaluated by real-time quantitative polymerase chain reaction [RT-qPCR] and western blot. Total glutathione [GSH] levels in colon samples were determined.. Prdx6-/- mice exposed to acute and chronic DSS showed a significant decrease in the clinical parameters and in colonic expression of pro-inflammatory cytokines compared with WT mice. mRNA expression of antioxidant enzymes in colon samples was significantly increased in Prdx6-/- compared with WT mice exposed to acute and chronic DSS. In addition, total GSH levels were increased in Prdx6-/- mice treated with DSS in comparison with WT. Overexpression of Prdx6 did not significantly influence acute and chronic colitis.. Our data indicate that a lack of the antioxidant enzyme PRDX6 protects against the development of acute and chronic experimental colitis and is associated with increased expression and function of other antioxidant enzymes, suggesting effective compensatory mechanisms. Topics: Acute Disease; Animals; Chronic Disease; Colitis; Colon; Cytokines; Dextran Sulfate; Endoscopy, Gastrointestinal; Epithelial Cells; Female; Glutamate-Cysteine Ligase; Glutathione; Glutathione Synthase; Humans; Inflammatory Bowel Diseases; Interferon-gamma; Interleukin-1beta; Interleukin-6; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; NF-E2-Related Factor 2; Nitric Oxide Synthase Type II; Peroxidase; Peroxiredoxin III; Peroxiredoxin VI; Peroxiredoxins; RNA, Messenger; Tumor Necrosis Factor-alpha | 2017 |
Protective Effect of Protocatechuic Acid on TNBS-Induced Colitis in Mice Is Associated with Modulation of the SphK/S1P Signaling Pathway.
(1) Background: The present study aimed to investigate whether beneficial effects of protocatechuic acid (PCA) are associated with inhibition of the SphK/S1P axis and related signaling pathways in a 2,4,6-trinitrobenzenesulfonic acid (TNBS) model of inflammatory bowel disease; (2) Methods: Colitis was induced in male Balb/c mice by intracolonic administration of 2 mg of TNBS. PCA (30 or 60 mg/kg body wt) was given intraperitoneally daily for five days; (3) Results: Administration of PCA prevented the macroscopic and microscopic damage to the colonic mucosa, the decrease in body weight gain and the increase in myeloperoxidase activity induced by TNBS. PCA-treated mice exhibited a lower oxidized/reduced glutathione ratio, increased expression of antioxidant enzymes and Nrf2 and reduced expression of proinflammatory cytokines. Following TNBS treatment mRNA levels, protein concentration and immunohistochemical labelling for SphK1 increased significantly. S1P production and expression of S1P receptor 1 and S1P phosphatase 2 were significantly elevated. However, there was a decreased expression of S1P lyase. Furthermore, TNBS-treated mice exhibited increased phosphorylation of AKT and ERK, and a higher expression of pSTAT3 and the NF-κB p65 subunit. PCA administration significantly prevented those changes; (4) Conclusions: Data obtained suggest a contribution of the SphK/S1P system and related signaling pathways to the anti-inflammatory effect of PCA. Topics: Animals; Colitis; Colon; Cyclooxygenase 2; Disease Models, Animal; Dose-Response Relationship, Drug; Down-Regulation; Glutathione; Hydroxybenzoates; Interleukin-1beta; Intestinal Mucosa; Male; Mice; Mice, Inbred BALB C; NF-kappa B; Oxidative Stress; Peroxidase; Phosphorylation; Phosphotransferases (Alcohol Group Acceptor); Proprotein Convertases; Serine Endopeptidases; Signal Transduction; STAT3 Transcription Factor; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Weight Gain | 2017 |
Polyphenol-rich grape pomace extracts protect against dextran sulfate sodium-induced colitis in rats.
Several studies have reported that polyphenols may exert beneficial effects on inflammatory bowel disease. This study aimed to evaluate the effects of preventive consumption of polyphenol-rich red grape pomace extracts (GPEs) on dextran sulfate sodium (DSS)-induced colitis in rats. Rats were fed for 21 days with a semi-synthetic diet enriched with a GPE (Alicante-S, Alicante-P or Pinot-S) and colitis was induced by DSS administration in drinking water (40 g L(-1) ) during the last 7 days of experimentation.. GPEs attenuated clinical signs and colon shortening and Alicante GPEs limited histological lesions induced by DSS. GPEs curbed the increase in myeloperoxidase activity and modulated antioxidant enzyme activities. Moreover, GPEs prevented the DSS-induced increase in pro-inflammatory cytokine levels and the up-regulation of various genes implicated in colitis such as intercellular adhesion molecule 1 (ICAM-1) and matrix metalloproteinase 9 (MMP-9).. These results suggest that polyphenol-rich red GPEs could provide prevention against colon inflammation. Topics: Animals; Antioxidants; Colitis; Colon; Cytokines; Dextran Sulfate; Fruit; Inflammation; Intercellular Adhesion Molecule-1; Male; Matrix Metalloproteinase 9; Oxidative Stress; Peroxidase; Plant Extracts; Polyphenols; Rats; Rats, Wistar; Up-Regulation; Vitis | 2016 |
Platelet-Derived CCL5 Regulates CXC Chemokine Formation and Neutrophil Recruitment in Acute Experimental Colitis.
Accumulating data suggest that platelets not only regulate thrombosis and haemostasis but also inflammatory processes. Platelets contain numerous potent pro-inflammatory compounds, including the chemokines CCL5 and CXCL4, although their role in acute colitis remains elusive. The aim of this study is to examine the role of platelets and platelet-derived chemokines in acute colitis. Acute colitis is induced in female Balb/c mice by administration of 5% dextran sodium sulfate (DSS) for 5 days. Animals receive a platelet-depleting, anti-CCL5, anti-CXCL4, or a control antibody prior to DSS challenge. Colonic tissue is collected for quantification of myeloperoxidase (MPO) activity, CXCL5, CXCL2, interleukin-6 (IL-6), and CCL5 levels as well as morphological analyses. Platelet depletion reduce tissue damage and clinical disease activity index in DSS-exposed animals. Platelet depletion not only reduces levels of CXCL2 and CXCL5 but also levels of CCL5 in the inflamed colon. Immunoneutralization of CCL5 but not CXCL4 reduces tissue damage, CXC chemokine expression, and neutrophil recruitment in DSS-treated animals. These findings show that platelets play a key role in acute colitis by regulating CXC chemokine generation, neutrophil infiltration, and tissue damage in the colon. Moreover, our results suggest that platelet-derived CCL5 is an important link between platelet activation and neutrophil recruitment in acute colitis. Topics: Acute Disease; Animals; Blood Platelets; Chemokine CCL5; Chemokines, CXC; Colitis; Disease Models, Animal; Female; Mice; Mice, Inbred BALB C; Neutrophil Infiltration; Peroxidase; Platelet Activation; Platelet Factor 4 | 2016 |
Fructooligosaccharides exert intestinal anti-inflammatory activity in the CD4+ CD62L+ T cell transfer model of colitis in C57BL/6J mice.
Fructooligosaccharides (FOS) are used as functional foods due to their prebiotic effects. Intestinal anti-inflammatory activity has been established in most, but not all, studies in animal models of colitis, using mainly chemically induced inflammation. Our goal was to test the effect of FOS (degree of polymerization 2-8) in the chronic, lymphocyte-driven CD4+ CD62L+ T cell transfer model of colitis.. Colitis was induced by transfer of CD4+ CD62L+ T cells to C57BL/6J Rag1(-/-) mice. FOS (75 mg day(-1)) was administered by gavage as a post-treatment. Three groups were established: non-colitic (NC), colitic control (C, CD4+ CD62L+ transferred mice treated with vehicle) and colitic+FOS (C+FOS, similar but treated with FOS). Mice were killed after 13 days.. Treatment of mice with FOS ameliorated colitis, as evidenced by an increase in body weight, a lesser myeloperoxidase and alkaline phosphatase activities, a lower secretion of proinflammatory cytokines by mesenteric lymph node cells ex vivo (IFN-γ, IL-17, and TNF-α), and a higher colonic expression of occludin (C+FOS vs. C, p < 0.05). Increased relative abundance of lactic acid bacteria was observed in FOS-treated mice (p < 0.05).. FOS exert intestinal anti-inflammatory activity in T lymphocyte-dependent colitis, suggesting it may be useful in the management of inflammatory bowel disease in appropriate conditions. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Calgranulin A; CD4-Positive T-Lymphocytes; Claudin-4; Claudin-5; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Gastrointestinal Microbiome; Gene Expression Regulation; Interferon-gamma; Interleukin-10; Interleukin-17; Interleukin-1beta; Intestinal Mucosa; Intestines; L-Selectin; Lactobacillus; Mice; Mice, Inbred C57BL; Occludin; Oligosaccharides; Peroxidase; Tumor Necrosis Factor-alpha | 2016 |
Maternal and neonatal dietary intake of balanced n-6/n-3 fatty acids modulates experimental colitis in young adult rats.
The imbalance of n-6 and n-3 polyunsaturated fatty acids in the maternal diet impairs intestinal barrier development and sensitizes the colon response to inflammatory insults in the young rats. With a view to overcoming this issue, we designed this study to investigate the effect of maternal and neonatal intake of different proportions of n-6/n-3 fatty acids on colon inflammation in the young adult rats.. Female Wistar rats were assigned into four groups, and each group fed one of four semisynthetic diets, namely n-6, low n-3, n-6/n-3 and n-3 fatty acids for 8 weeks prior to mating, during gestation and lactation periods. At weaning, the pups were separated from the dams and fed diet similar to the mothers. Colitis was induced on postnatal day 35, by administering 2 % dextran sulfate sodium in drinking water for 10 days. Colitis was assessed based on the clinical and inflammatory markers in the colon. Fatty acid analysis was done in liver, RBC, colon and spleen.. A balanced n-6/n-3 PUFA diet significantly improved the body weight loss, rectal bleeding and mortality in rats. This was associated with lower myeloperoxidase activity, nitric oxide, prostaglandin E2, TNF-α and IL-6, IL-8, COX-2 and iNOS levels in the colon tissues. Fatty acid analysis has shown that the arachidonic acid/docosahexaenoic acid ratio was significantly lower in liver, RBC, colon and spleen in n-6/n-3 and n-3 diet groups.. We demonstrate that balanced n-6/n-3 PUFA supplementation in maternal and neonatal diet alters systemic AA/DHA ratio and attenuates colon inflammation in the young adult rats. Topics: Animals; Animals, Newborn; Colitis; Colon; Cyclooxygenase 2; Dextran Sulfate; Diet; Dinoprostone; Disease Models, Animal; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Female; Interleukin-6; Interleukin-8; Maternal Nutritional Physiological Phenomena; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha | 2016 |
Therapeutic and immunoregulatory effect of GATA-binding protein-3/T-box expressed in T-cells ratio of astragalus polysaccharides on 2,4,6-trinitrobenzene sulfonic acid-induced colitis in rats.
To analyze the immunological characteristics of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis model and examine the therapeutic effects and mechanisms of Astragalus polysaccharides (APS) treatment.. Thirty-two male specific pathogen free Spragne-Dawley rats were randomly equally assigned to four groups: control, TNBS, APS and prednisone groups. Experimental colitis was induced by enema administration of TNBS. Then rats were treated with APS (0.5 g•kg. Both macroscopic lesion and histological colonic damage induced by TNBS were reduced by APS and prednisone treatment. These were accompanied by significant attenuation of MPO activity (P=0.03). TNBS intervention enhanced the expression of both GATA-3 and T-bet, but the expression of T-bet was significantly enhanced than that of GATA-3, resulting in significant reduction of GATA-3/T-bet ratio (P=0.025). APS administration enhanced the expression of T-bet (P=0.04) and GATA-3 (P=0.019) in comparison to TNBS group, and resulting in an up-regulated GATA-3/T-bet ratio. Prednisone treatment inhibited both expressions; however it also resulted in up-regulation of the GATA-3/T-bet ratio.. These results demonstrated that APS exerted a beneficial immune regulatory effect on experimental colitis. It promoted the expression of T helper cell 1 (Th1) and T helper cell 2 (Th2) specific transcription factors but ultimately favor a shift toward Th2 phenotype, suggesting that APS possessed therapeutic potential in experimental colitis. Topics: Animals; Astragalus Plant; Blotting, Western; Colitis; Colon; GATA3 Transcription Factor; Immunohistochemistry; Immunomodulation; Male; Peroxidase; Polysaccharides; Rats, Sprague-Dawley; T-Box Domain Proteins; Trinitrobenzenesulfonic Acid | 2016 |
Activation of colo-rectal high-threshold afferent nerves by Interleukin-2 is tetrodotoxin-sensitive and upregulated in a mouse model of chronic visceral hypersensitivity.
Chronic visceral pain is a defining feature of irritable bowel syndrome (IBS). IBS patients often show alterations in innate and adaptive immune function which may contribute to symptoms. Immune mediators are known to modulate the activity of viscero-sensory afferent nerves, but the focus has been on the innate immune system. Interleukin-2 (IL-2) is primarily associated with adaptive immune responses but its effects on colo-rectal afferent function in health or disease are unknown.. Myeloperoxidase (MPO) activity determined the extent of inflammation in health, acute trinitrobenzene-sulfonic acid (TNBS) colitis, and in our post-TNBS colitis model of chronic visceral hypersensitivity (CVH). The functional effects of IL-2 on high-threshold colo-rectal afferents and the expression of IL-2R and NaV 1.7 mRNA in colo-rectal dorsal root ganglia (DRG) neurons were compared between healthy and CVH mice.. MPO activity was increased during acute colitis, but subsided to levels comparable to health in CVH mice. IL-2 caused direct excitation of colo-rectal afferents that was blocked by tetrodotoxin. IL-2 did not affect afferent mechanosensitivity in health or CVH. However, an increased proportion of afferents responded directly to IL-2 in CVH mice compared with controls (73% vs 33%; p < 0.05), and the abundance of IL-2R and NaV 1.7 mRNA was increased 3.5- and 2-fold (p < 0.001 for both) in colo-rectal DRG neurons.. IL-2, an immune mediator from the adaptive arm of the immune response, affects colo-rectal afferent function, indicating these effects are not restricted to innate immune mediators. Colo-rectal afferent sensitivity to IL-2 is increased long after healing from inflammation. Topics: Adaptive Immunity; Afferent Pathways; Animals; Colitis; Disease Models, Animal; Ganglia, Spinal; Hyperalgesia; Interleukin-2; Irritable Bowel Syndrome; Mice; NAV1.7 Voltage-Gated Sodium Channel; Neurons, Afferent; Peroxidase; Real-Time Polymerase Chain Reaction; Receptors, Interleukin-2; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sodium Channel Blockers; Tetrodotoxin; Trinitrobenzenesulfonic Acid; Visceral Pain | 2016 |
Protective Effect of Ocimum basilicum Essential Oil Against Acetic Acid-Induced Colitis in Rats.
Ocimum basilicum L has been traditionally used for the treatment of inflammatory bowel disease in Iran. This study investigates the ameliorative effect of Ocimum basilicum essential oil on an acetic acid-induced colitis model in rats. Ocimum basilicum essential oil with 2 doses (200 and 400 μL/kg) significantly ameliorated wet weight/length ratio of colonic tissue compared to the control group. Higher doses of essential oil (200 and 400 μL/kg) significantly reduced ulcer severity, ulcer area, and ulcer index. On the other hand, histological examination revealed the diminution of total colitis index as a marker for inflammatory cell infiltration in the colonic segments of rats treated with Ocimum basilicum essential oil (200 and 400 μL/kg). The increased level of myeloperoxidase was significantly decreased after the treatment with the essential oil (200 and 400 μL/kg). These results suggest that Ocimum basilicum exhibits protective effect against acetic acid-induced colitis. Topics: Acetic Acid; Animals; Colitis; Colon; Disease Models, Animal; Iran; Male; Ocimum basilicum; Oils, Volatile; Peroxidase; Protective Agents; Rats; Rats, Wistar | 2016 |
Novel anti-inflammatory agent 3-[(dodecylthiocarbonyl)-methyl]-glutarimide ameliorates murine models of inflammatory bowel disease.
To examine the effect of 3-[(dodecylthiocarbonyl)-methyl]-glutarimide (DTCM-G), a novel anti-inflammatory agent that inhibits lipopolysaccharide (LPS) activation of RAW264.7 macrophages, on murine models of colitis and RAW264.7 cells.. Colitis was induced by rectally infusing trinitrobenzenesulfonic acid (TNBS) (1.5 mg in 50% ethanol) in BALB/c mice or orally administering 3% dextran sulfate sodium (DSS) for 5 days in C57BL/6 mice. The severity of colitis was assessed after intraperitoneally injecting DTCM-G (40 mg/kg). The anti-inflammatory properties of DTCM-G and its mechanisms were investigated in LPS-stimulated RAW264.7 cells.. DTCM-G significantly ameliorated TNBS-induced colitis, according to the body weight loss, disease activity index, colonic obstruction, macroscopic colonic inflammation score, mucosal myeloperoxidase activity, and histopathology. Immunohistochemistry and isolated lamina propria mononuclear cells showed significantly reduced colonic F4/80(+) and CD11b(+) macrophage infiltration. DTCM-G significantly suppressed tumor necrosis factor (TNF)-α and interleukin (IL)-6 messenger RNA expression in the colon and attenuated DSS-induced colitis, according to the disease activity index and histopathology. In RAW264.7 cells, DTCM-G suppressed LPS-induced TNF-α/IL-6 production and enhanced glycogen synthase kinase-3β phosphorylation.. DTCM-G attenuated murine experimental colitis by inhibiting macrophage infiltration and inflammatory cytokine expression. Thus, DTCM-G may be a promising treatment for inflammatory bowel disease. Topics: Animals; Anti-Inflammatory Agents; CD4-Positive T-Lymphocytes; Cell Line; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Macrophages; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Peroxidase; Piperidones; RNA, Messenger; Trinitrobenzenesulfonic Acid | 2016 |
Isoliquiritigenin ameliorates dextran sulfate sodium-induced colitis through the inhibition of MAPK pathway.
Isoliquiritigenin (isoLQ), a chalcone found in licorice, has shown a variety of biological activity including anti-inflammatory and antioxidative effects, and the distribution of isoLQ in gastrointestinal tract was higher than any other tissues. Thus, we evaluated whether or not isoLQ attenuated the dextran sulfate sodium (DSS)-induced colitis by observing the physiological changes (body weight loss, diarrhea, bleeding stool, overall disease activity index (DAI) scores, colon length), histopathological analysis and myeloperoxidase (MPO) activities of esophagus and colon. Also, the MAPK pathways including phosphorylation of ERK1/2, p38, and AKT, and the activation of NK-κB were evaluated in colon tissue. Interestingly, the reduction of body weight and colon length, increase of diarrhea, bloody stool, DAI scores and MPO activity, and histologic disturbances in DSS-induced colitis were recovered by isoLQ treatment. Also, isoLQ treatment suppressed the phosphorylation of ERK1/2 and p38, and the activation of NK-κB compared to those in DSS-induced colitis mice. In addition, the distributions of isoLQ in colon were relatively higher in DSS-induced colitis models. All of these results suggested that isoLQ has potential activity to ameliorate the DSS-induced colitis through the inhibition of MAPK pathway. Topics: Animals; Anti-Inflammatory Agents; Chalcones; Colitis; Colon; Dextran Sulfate; Disease Progression; Extracellular Signal-Regulated MAP Kinases; Glycyrrhiza; Male; Mice; Mice, Inbred ICR; NF-kappa B; Peroxidase; Signal Transduction | 2016 |
Protective effect of melatonin on myenteric neuron damage in experimental colitis in rats.
Inflammation of the colon in patients with ulcerative colitis (UC) causes pain and altered motility, at least in part through the damage of the myenteric neurons (MNs). Thus, it is important to evaluate new drugs for UC treatment that could also protect myenteric neurons efficiently. As a well-known neural protective and anti-inflammatory agent, melatonin could protect neurons from damage through the activation of the nuclear factor erythroid 2-related factor 2 and antioxidant responsive element (Nrf2-ARE) signaling pathway. Therefore, we investigated the potential protective effect of melatonin against MN damage during colitis induced by 2,4-dinitrobenzene sulfonic acid (DNBS) in rats. Colitis was induced by intracolonic (i.c.) instillation of DNBS and treated with melatonin at a dose of 2.5 mg/kg for 4 days. The damage of MN in the left colon was immunohistochemically evaluated in different groups. Ulcerations and inflammation in the colon were semiquantitatively observed. Myeloperoxidase (MPO), superoxide dismutase (SOD), and malondialdehyde (MDA) levels were detected to evaluate the inflammatory and oxidative stress status. The protein and mRNA expressions of Nrf2 and heme oxygenase-1 (HO-1) in the colon were detected by Western blot and quantitative polymerase chain reaction (qPCR), respectively. Melatonin partially prevented the loss of MN and alleviated the inflammation and oxidative stress induced by DNBS. In addition, melatonin markedly increased the Nrf2 and HO-1 level in the colitis. These results indicate that melatonin protects MN from damage by reducing inflammation and oxidative stress, effects that are partly mediated by the Nrf2-ARE pathway. Topics: Animals; Colitis; Colon; Dinitrofluorobenzene; Disease Models, Animal; Heme Oxygenase-1; Inflammation; Malondialdehyde; Melatonin; Neurons; Oxidative Stress; Peroxidase; Protective Agents; Rats; Superoxide Dismutase | 2016 |
Obestatin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats.
Obestatin, a 23-amino acid peptide derived from the proghrelin, has been shown to exhibit some protective and therapeutic effects in the gut. The aim of present study was to determine the effect of obestatin administration on the course of acetic acid-induced colitis in rats. Materials and Methods. Studies have been performed on male Wistar rats. Colitis was induced by a rectal enema with 3.5% acetic acid solution. Obestatin was administered intraperitoneally twice a day at a dose of 8 nmol/kg, starting 24 h after the induction of colitis. Seven or 14 days after the induction of colitis, the healing rate of the colon was evaluated. Results. Treatment with obestatin after induction of colitis accelerated the healing of colonic wall damage and this effect was associated with a decrease in the colitis-evoked increase in mucosal activity of myeloperoxidase and content of interleukin-1β. Moreover, obestatin administration significantly reversed the colitis-evoked decrease in mucosal blood flow and DNA synthesis. Conclusion. Administration of exogenous obestatin exhibits therapeutic effects in the course of acetic acid-induced colitis and this effect is related, at least in part, to the obestatin-evoked anti-inflammatory effect, an improvement of local blood flow, and an increase in cell proliferation in colonic mucosa. Topics: Acetic Acid; Animals; Colitis; Colon; DNA; Ghrelin; Injections, Intraperitoneal; Interleukin-1beta; Intestinal Mucosa; Male; Peroxidase; Rats, Wistar; Regional Blood Flow; Sodium Chloride; Wound Healing | 2016 |
The efficacy of tyrosine kinase inhibitor dasatinib on colonic mucosal damage in murine model of colitis.
Ulcerative colitis is an inflammatory condition of the colon in the gastrointestinal system. Currently, the most potent medications used for ulcerative colitis produce no response in 20-30% of cases. There is a need for more efficient and reliable medications. Tyrosine kinase inhibitors have shown efficacy in some inflammatory diseases. Although dasatinib, a tyrosine kinase inhibitor, suppresses proinflammatory cytokines in colonic tissue, there are a few cases of hemorrhagic colitis with dasatinib. There is no study investigating the effect of dasatinib on experimental colitis. We aimed to investigate the effect of dasatinib in a colitis model induced with acetic acid in our study.. In the study, 24 male Sprague-Dawley rats randomly distributed into 4 groups of 6 rats each as control, dasatinib, colitis and dasatinib+colitis groups. For colitis induction, 4% acetic acid was used. Sacrificing of the rats was performed on the seventh day. Disease activity, morphologic and histological injury, superoxide dismutase, myeloperoxidase and malondialdehyde activity, TNFα and CD3 expression were assessed in colonic tissue.. Apart from malondialdehyde, significant difference in all parameters between the control and colitis groups was determined. Difference between the colitis and colitis+dasatinib groups was not significant in only weight loss and biochemical parameters. Though dasatinib does not fully resolve the changes in colitis, there was significant regression.. Dasatinib decreased the inflammation in a rodent model of colitis. It may be provide this effect by the suppression of TNFα. Dasatinib may be one of the treatment options for ulcerative colitis. Topics: Animals; Colitis; Colon; Dasatinib; Disease Models, Animal; Intestinal Mucosa; Malondialdehyde; Peroxidase; Protein Kinase Inhibitors; Rats, Sprague-Dawley; Superoxide Dismutase; Weight Loss | 2016 |
5-fluorouracil attenuates dextran sodium sulfate-induced acute colitis in mice.
5‑Fluorouracil (5‑FU) has been predominantly used in the clinic for cancer chemotherapy. Previous studies have demonstrated that 5‑FU has an anti‑inflammatory function. In the current study, the potential therapeutic role of 5‑FU in dextran sodium sulfate (DSS)‑induced acute mouse colitis was investigated. Effects on the severity of colitis were studied via histochemical and immunohistochemical staining, cytokine levels were determined by reverse transcriptoin‑quantitative polymerase chain reaction and the effect of 5‑FU on NF‑κB was examined by western blotting. Administration of 5‑FU ameliorated the severity of acute DSS‑induced colitis. The disease activity score was significantly lower in the 5‑FU + DSS‑treated mice compared with the DSS‑treated group (P<0.01). Tumor necrosis factor‑α, interleukin‑1β and interferon γ mRNA expression levels were significantly downregulated in the colon tissue of DSS mice treated with 5‑FU compared with the untreated DSS mice (P<0.05). In addition, the number of CD4+ T cells in the colonic lamina propria and myeloperoxidase activity were significantly decreased in the 5‑FU + DSS‑treated mice (P<0.05). Furthermore, 5‑FU treatment significantly reduced p‑NF‑κB‑p56 protein expression levels in the colon tissue of DSS‑treated mice (P<0.05). The present results demonstrated that 5‑FU minimizes the abnormal immune cytokine response and relieves the pathophysiological disorders associated with experimental acute colitis. Thus, the modulating inflammatory response role of 5‑FU may be partially associated with inhibiting NF‑κB activation and 5‑FU may be a novel therapeutic strategy for the treatment of inflammatory bowel disease. Topics: Animals; Anti-Inflammatory Agents; CD4-Positive T-Lymphocytes; Colitis; Dextran Sulfate; Drug Evaluation, Preclinical; Female; Fluorouracil; Intestinal Mucosa; Mice, Inbred BALB C; NF-kappa B; Peroxidase | 2016 |
Melatonin, but not melatonin receptor agonists Neu-P11 and Neu-P67, attenuates TNBS-induced colitis in mice.
Melatonin is known as a strong antioxidant and possesses anti-inflammatory properties. Recently, melatonin was shown to improve colitis in animal models of inflammatory bowel diseases. The aim of the present study was to characterize the role of melatonin receptors (MT) in the anti-inflammatory effect of melatonin and to assess the anti-inflammatory potential of two novel MT receptor agonists, Neu-P11 and Neu-P67, in the mouse model of trinitrobenzenesulfonic acid (TNBS)-induced colitis. Colitis was induced on day 1 by intracolonic (i.c.) administration of TNBS in 30 % ethanol in saline. Melatonin (4 mg/kg, per os (p.o.)), Neu-P11 (20 mg/kg, p.o.; 50 mg/kg, intraperitoneally (i.p.), 50 mg/kg, i.c.), and Neu-P67 (20 mg/kg, p.o.) were given twice daily for 3 days. Luzindole (5 mg/kg, i.p.) was injected 15 min prior to melatonin administration. On day 4, macroscopic and microscopic damage scores were assessed and myeloperoxidase (MPO) activity quantified using O-dianisidine-based assay. Melatonin significantly attenuated colitis in mice, as indicated by the macroscopic score (1.90 ± 0.34 vs. 3.82 ± 0.62 for melatonin- and TNBS-treated mice, respectively), ulcer score (0.87 ± 0.18 vs. 1.31 ± 0.19, respectively), and MPO activity (4.68 ± 0.70 vs.6.26 ± 0.94, respectively). Luzindole, a MT receptor antagonist, did not inhibit the anti-inflammatory effect of melatonin (macroscopic score 1.12 ± 0.22, ulcer score 0.50 ± 0.16); however, luzindole increased MPO activity (7.57 ± 1.05). MT receptor agonists Neu-P11 and Neu-P67 did not improve inflammation induced by TNBS. Melatonin, but not MT receptor agonists, exerts potent anti-inflammatory action in acute TNBS-induced colitis. Our data suggests that melatonin attenuates colitis by additional, MT receptor-independent pathways. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Indoles; Male; Melatonin; Mice, Inbred BALB C; Peroxidase; Pyrans; Receptors, Melatonin; Trinitrobenzenesulfonic Acid | 2016 |
Neomangiferin modulates the Th17/Treg balance and ameliorates colitis in mice.
Anemarrhena asphodeloides (Liliaceae family) and Mangifera indica L. (Anacardiaceae family) contain neomangiferin as the main active constituent and have been used to treat inflammation, asthma, and pain.. A preliminary study found that neomangiferin inhibited splenic T cell differentiation into Th17 cells and promoted Treg cell production in vitro. Therefore, we examined its anti-colitic effects in vitro and in vivo.. Splenocytes isolated from C57BL/6J mice were treated with neomangiferin. Colitis was either induced in vivo by intrarectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) to C57BL/6J mice or occurred spontaneously in colitis caused by interleukin (IL)-10 knockout at age of 13 weeks. Mice were treated daily with neomangiferin or sulfasalazine. Inflammatory markers, cytokines, enzymes and transcription factors were measured by enzyme-linked immunosorbent assay, immunoblot, and flow cytometry.. Neomangiferin suppressed retinoic acid receptor-related orphan receptor gamma t (RORγt) and IL-17 expression in IL-6/transforming growth factor β-stimulated Th17 splenocytes and increased IL-10 expression in vitro. Mouse TNBS-induced colon shortening, macroscopic score, and myeloperoxidase activity were inhibited by neomangiferin, which also reduced TNBS-induced activation of nuclear factor-κB and extracellular signal-regulated kinases, as well as expression of inducible nitric oxide synthase and cyclooxygenase-2. In addition, neomangiferin inhibited TNBS-induced expression of tumor necrosis factor-α, IL-17, IL-6, and IL-1β, and increased IL-10 expression. Neomangiferin inhibited TNBS-induced differentiation to Th17 cells and promoted the development of Treg cells. Moreover, in IL-10(-/-) mice, neomangiferin inhibited colonic myeloperoxidase activity, suppressed Th17 cell differentiation, and reduced levels of TNF-α and IL-17.. Neomangiferin may restore the balance between Th17/Treg cells by suppressing IL-17 and RORγt expression and inducing IL-10 and forkhead box P3 expression, thus ameliorating colitis. Topics: Animals; Anti-Inflammatory Agents; Cell Differentiation; Colitis; Colon; Cyclooxygenase 2; Extracellular Signal-Regulated MAP Kinases; Forkhead Transcription Factors; Glucosides; Interleukin-10; Interleukin-17; Interleukin-6; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; NF-kappa B; Nuclear Receptor Subfamily 1, Group F, Member 3; Peroxidase; T-Lymphocytes, Regulatory; Th17 Cells; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Xanthones | 2016 |
Oroxyloside prevents dextran sulfate sodium-induced experimental colitis in mice by inhibiting NF-κB pathway through PPARγ activation.
Oroxyloside, as a metabolite of oroxylin A, may harbor various beneficial bioactivities which have rarely been reported in the previous studies. Here we established the dextran sulfate sodium (DSS)-induced experimental colitis and evaluated the anti-inflammatory effect of oroxyloside in vivo. As a result, oroxyloside attenuated DSS-induced body weight loss, colon length shortening and colonic pathological damage. Furthermore, oroxyloside inhibited inflammatory cell infiltration and decreased myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) activities as well. The production of pro-inflammatory cytokines in serum and colon was also significantly reduced by oroxyloside. We unraveled the underlying mechanisms that oroxyloside inhibited NF-κB pathway by activating Peroxisome Proliferator-Activated Receptor γ (PPARγ) to attenuate DSS-induced colitis. Moreover, we investigated the anti-inflammatory effect and mechanisms of oroxyloside in the mouse macrophage cell line RAW264.7 and bone marrow derived macrophages (BMDM). Oroxyloside decreased several LPS-induced inflammatory cytokines, including IL-1β, IL-6 and TNF-α in RAW264.7 and BMDM. We also found that oroxyloside inhibited LPS-induced activation of NF-κB signaling pathway via activating PPARγ in RAW 264.7 and BMDM. Docking study showed that oroxyloside could bind with PPARγ. GW9662, the inhibitor of PPARγ, and PPARγ siRNA transfection blocked the effect of oroxyloside on PPARγ activation. Our study suggested that oroxyloside prevented DSS-induced colitis by inhibiting NF-κB pathway through PPARγ activation. Therefore, oroxyloside may be a promising and effective agent for inflammatory bowel disease (IBD). Topics: Anilides; Animals; Anti-Inflammatory Agents, Non-Steroidal; Cell Line; Colitis; Dextran Sulfate; Disease Models, Animal; Female; Flavones; Gene Expression Regulation; Glucuronides; Interleukin-1beta; Interleukin-6; Macrophages; Mice; Mice, Inbred C57BL; Molecular Docking Simulation; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; PPAR gamma; RNA, Small Interfering; Signal Transduction; Tumor Necrosis Factor-alpha | 2016 |
Cyclosporine A-loaded lipid nanoparticles in inflammatory bowel disease.
Cyclosporine A (CsA) is a well-known immunosuppressive agent used as rescue therapy in severe steroid-refractory ulcerative colitis (UC). However, toxicity issues associated with CsA when administered in its commercially available formulations have been reported in clinical practice. Since nanotechnology has been proposed as a promising strategy to improve safety and efficacy in the treatment of inflammatory bowel disease (IBD), the main purpose of this study was to evaluate the effect of oral administration of CsA-loaded lipid nanoparticles (LN) in the dextran sodium sulfate (DSS)-induced colitis mouse model using Sandimmune Neoral(®) as reference. The results showed that the formulations used did not decrease colon inflammation in terms of myeloperoxidase activity (MPO), tumor necrosis factor (TNF)-α expression, or histological scoring in the acute stage of the disease. However, further studies are needed in order to corroborate the efficacy of these formulations in the chronic phase of the disease. Topics: Animals; Colitis; Colon; Cyclosporine; Dextran Sulfate; Disease Models, Animal; Female; Immunosuppressive Agents; Mice, Inbred C57BL; Nanoparticles; Peroxidase; Tumor Necrosis Factor-alpha | 2016 |
Experimental and Pathalogical study of Pistacia atlantica, butyrate, Lactobacillus casei and their combination on rat ulcerative colitis model.
This study evaluated the effects of Pistacia atlantica (P. atlantica), butyrate, Lactobacillus casei (L. casei) and especially their combination therapy on 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced rat colitis model. Rats were divided into seven groups. Four groups received oral P. atlantica, butyrate, L. casei and the combination of three agents for 10 consecutive days. The remaining groups were negative and positive controls and a sham group. Macroscopic and histopathological examinations were carried out along with determination of the specific biomarker of colonic oxidative stress, the myeloperoxidase (MPO). Compared with controls, the combination therapy exhibited a significant alleviation of colitis in terms of pathological scores and reduction of MPO activity (55%, p=0.0009). Meanwhile, the macroscopic appearance such as stool consistency, tissue and histopathological scores (edema, necrosis and neutrophil infiltration) were improved. Although single therapy by each P. atlantica, butyrate, and L. casei was partially beneficial in reduction of colon oxidative stress markers, the combination therapy was much more effective. In conclusion, the combination therapy was able to reduce the severity of colitis that is clear from biochemical markers. Future studies have to focus on clinical effects of this combination in management of human ulcerative colitis. Further molecular and signaling pathway studies will help to understand the mechanisms involved in the treatment of colitis and inflammatory diseases. Topics: Animals; Butyrates; Colitis; Colon; Disease Models, Animal; Drug Therapy, Combination; Lacticaseibacillus casei; Male; Oxidative Stress; Peroxidase; Pistacia; Plant Extracts; Probiotics; Rats; Rats, Wistar; Treatment Outcome; Trinitrobenzenesulfonic Acid | 2016 |
Goniothalamin prevents the development of chemically induced and spontaneous colitis in rodents and induces apoptosis in the HT-29 human colon tumor cell line.
Colon cancer is the third most incident type of cancer worldwide. One of the most important risk factors for colon cancer development are inflammatory bowel diseases (IBD), thus therapies focusing on IBD treatment have great potential to be used in cancer prevention. Nature has been a source of new therapeutic and preventive agents and the racemic form of the styryl-lactone goniothalamin (GTN) has been shown to be a promising antiproliferative agent, with gastroprotective, antinociceptive and anti-inflammatory effects. As inflammation is a well-known tumor promoter, the major goal of this study was to evaluate the therapeutic and preventive potentials of GTN on chemically induced and spontaneous colitis, as well as the cytotoxic effects of GTN on a human colon tumor cell line (HT-29). GTN treatments inhibited TNBS-induced acute and chronic colitis development in Wistar rats, reducing myeloperoxidase levels and inflammatory cells infiltration in the mucosa. In spontaneous-colitis using IL-10 deficient mice (C57BL/6 background), GTN prevented colitis development through downregulation of TNF-α, upregulation of SIRT-1 and inhibition of proliferation (PCNA index), without signs of toxicity after three months of treatment. In HT-29 cells, treatment with 10μM of GTN induced apoptosis by increasing BAX/BCL2, p-JNK1/JNK1, p-P38/P38 ratios as well as through ROS generation. Caspase 8, 9 and 3 activation also occurred, suggesting caspase-dependent apoptotic pathway, culminating in PARP-1 cleavage. Together with previous data, these results show the importance of GTN as a pro-apoptotic, preventive and therapeutic agent for IBD and highlight its potential as a chemopreventive agent for colon cancer. Topics: Animals; Apoptosis; Caspases; Cell Cycle; Cell Line, Tumor; Colitis; Colonic Neoplasms; Down-Regulation; HT29 Cells; Humans; Interleukin-10; Leukocytes; Male; Mice, Inbred C57BL; Peroxidase; Pyrones; Rats; Rats, Wistar; Sirtuin 1; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Up-Regulation | 2016 |
Preserving viability of Lactobacillus rhamnosus GG in vitro and in vivo by a new encapsulation system.
Probiotics have shown beneficial effects on health and prevention of diseases in humans. However, a concern for application of probiotics is the loss of viability during storage and gastrointestinal transit. The aim of this study was to develop an encapsulation system to preserve viability of probiotics when they are administrated orally and apply Lactobacillus rhamnosus GG (LGG) as a probiotic model to evaluate the effectiveness of this approach using in vitro and in vivo experiments. LGG was encapsulated in hydrogel beads prepared using pectin, a food grade polysaccharide, glucose, and calcium chloride, and lyophilized by freeze-drying. Encapsulated LGG was cultured in vitro under the condition that mimicked the physiological environment of the human gastrointestinal tract. Compared to non-encapsulated LGG, encapsulation increased tolerance of LGG in the acid condition, protected LGG from protease digestion, and improved shelf time when stored at the ambient condition, in regard of survivability and production of p40, a known LGG-derived protein involved in LGG's beneficial effects on intestinal homeostasis. To evaluate the effects of encapsulation on p40 production in vivo and prevention of intestinal inflammation by LGG, mice were gavaged with LGG containing beads and treated with dextran sulphate sodium (DSS) to induce intestinal injury and colitis. Compared to non-encapsulated LGG, encapsulated LGG enhanced more p40 production in mice, and exerted higher levels of effects on prevention of DSS-induced colonic injury and colitis and suppression of pro-inflammatory cytokine production. These data indicated that the encapsulation system developed in this study preserves viability of LGG in vitro and in vivo, leading to longer shelf time and enhancing the functions of LGG in the gastrointestinal tract. Thus, this encapsulation approach may have the potential application for improving efficacy of probiotics. Topics: Administration, Oral; Animals; Bacterial Proteins; Calcium Chloride; Colitis; Colon; Colony Count, Microbial; Dextran Sulfate; Feces; Glucose; Hydrogels; Hydrogen-Ion Concentration; Lacticaseibacillus rhamnosus; Mice, Inbred C57BL; Microspheres; Pectins; Peroxidase; Probiotics | 2016 |
Lactobacillus reuteri increases mucus thickness and ameliorates dextran sulphate sodium-induced colitis in mice.
The aim of this study was to investigate whether two Lactobacillus reuteri strains (rat-derived R2LC and human-derived ATCC PTA 4659 (4659)) could protect mice against colitis, as well as delineate the mechanisms behind this protection.. Mice were given L. reuteri R2LC or 4659 by gavage once daily for 14 days, and colitis was induced by addition of 3% DSS (dextran sulphate sodium) to drinking water for the last 7 days of this period. The severity of disease was assessed through clinical observations, histological evaluation and ELISA measurements of myeloperoxidase (MPO) and pro-inflammatory cytokines from colonic samples. Mucus thickness was measured in vivo with micropipettes, and tight junction protein expression was assessed using immunohistochemistry.. Colitis severity was significantly reduced by L. reuteri R2LC or 4659 when evaluated both clinically and histologically. The inflammation markers MPO, IL-1β, IL-6 and mKC (mouse keratinocyte chemoattractant) were increased by DSS and significantly reduced by the L. reuteri strains. The firmly adherent mucus thickness was reduced by DSS, but significantly increased by L. reuteri in both control and DSS-treated mice. Expression of the tight junction proteins occludin and ZO-1 was significantly increased in the bottom of the colonic crypts by L. reuteri R2LC.. These results demonstrate that each of the two different L. reuteri strains, one human-derived and one-rat-derived, protects against colitis in mice. Mechanisms behind this protection could at least partly be explained by the increased mucus thickness as well as a tightened epithelium in the stem cell area of the crypts. Topics: Animals; Colitis; Colon; Cytokines; Dextran Sulfate; Limosilactobacillus reuteri; Male; Mice; Mice, Inbred C57BL; Mucus; Peroxidase; Probiotics; Rats; Tight Junction Proteins; Viscosity | 2016 |
Disruption of Tumor Necrosis Factor Receptor-Associated Factor 5 Exacerbates Murine Experimental Colitis via Regulating T Helper Cell-Mediated Inflammation.
Tumor necrosis factor (TNF) receptor-associated factor 5 (TRAF5) is a key mediator of TNF receptor superfamily members and is important in both T helper (Th) cell immunity and the regulation of multiple signaling pathways. To clarify TRAF5's influence on inflammatory bowel diseases (IBDs), we investigated TRAF5 deficiency's effect on dextran sulfate sodium- (DSS-) induced colitis. Colitis was induced in TRAF5 knockout (KO) mice and their wild-type (WT) littermates by administering 3% DSS orally for 7 days. The mice were then sacrificed, and their colons were removed. Our data suggested that KO mice were more susceptible to DSS-induced colitis. TRAF5 deficiency significantly enhanced IFN-γ, IL-4, and IL-17a mRNA and protein levels in the colons of DSS-fed mice, and the mRNA expression of T-bet and GATA-3 was also markedly elevated. However, ROR-α and ROR-γt mRNA levels did not differ between DSS-induced KO and WT mice. Flow cytometry showed increased frequencies of Th2 and IFN-γ/IL-17a-coproducing CD4(+) T cells in the colons of DSS-induced KO mice. Additionally, TRAF5 deficiency significantly enhanced the activation of NF-κB in CD4(+) T cells after DSS administration. These results indicated that TRAF5 deficiency significantly aggravated DSS-induced colitis, most likely by regulating Th cell-mediated inflammation. Topics: Animals; Blotting, Western; CD4-Positive T-Lymphocytes; Colitis; Dextran Sulfate; Disease Models, Animal; Electrophoresis, Polyacrylamide Gel; Female; Flow Cytometry; Inflammation; Interleukin-17; Male; Mice; Mice, Knockout; Peroxidase; Real-Time Polymerase Chain Reaction; RNA, Messenger; T-Lymphocytes, Helper-Inducer; TNF Receptor-Associated Factor 5 | 2016 |
Anti-inflammatory effects of Citrus sinensis L., Citrus paradisi L. and their combinations.
Citrus bioflavonoids embrace a wide group of phenolic compounds effecting the production and scavenging of reactive oxygen species and the processes relating free radical-mediated injury. Keeping in view of the antioxidant and anti-inflammatory properties of Citrus sinensis and Citrus paradisi, present study was undertaken to explore the effects of C. sinensis (orange juice) and C. paradisi (grapefruit juice) at three different doses alone and their two combinations with the objective to examine the effects of these compounds in an experimental model of rat colitis induced by trinitrobenzenesulphonic acid (TNBS). Hence biochemical parameters e.g. myeloperoxidase, alkaline phosphatase, C-reactive protein (CRP) and glutathione were assessed. Data entry and analysis was accomplished by Statistical Package for the Social Sciences version 17 and was presented as mean ± S.E.M with 95% confidence interval. Present result shows that these juices, mainly C. paradisi, may be efficacious for the management of inflammatory bowel disease. In acute colitis model, C. paradise encouraged a decrease in the extension of the lesion escorted by a decrease in the occurrence of diarrhea and reinstatement of the glutathione content. Related effects were produced by the administration of C. sinensis, which also prevented the myeloperoxidase and alkaline phosphatase actions in acute intestinal inflammatory process. The effect of the citrus juices on the inflammatory process may be associated to their antioxidant and anti-inflammatory properties, as revealed in present investigation. The favorable effects exerted were demonstrated both by histological and biochemical changes and were related with a progress in the colonic oxidative status. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; C-Reactive Protein; Citrus paradisi; Citrus sinensis; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Therapy, Combination; Fruit; Fruit and Vegetable Juices; Glutathione; Inflammation Mediators; Male; Oxidative Stress; Peroxidase; Phytotherapy; Plant Extracts; Plants, Medicinal; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2016 |
Halofuginone reduces the inflammatory responses of DSS-induced colitis through metabolic reprogramming.
Hypoxia and inflammation have been identified as the hallmarks of colitis, intertwined with metabolism. Here, we report that halofuginone (HF), an antiparasitic drug, attenuates dextran sulfate sodium (DSS)-induced colitis in mice, as represented by attenuating the disease activity index, inhibiting colonic shortening, ameliorating colonic lesions and histological signs of damage, reducing colonic myeloperoxidase activity, and suppressing the production of pro-inflammatory cytokines in colon tissue. Intriguingly, the hypoxia-inducible factor 1alpha (HIF-1α) and tumor necrosis factor alpha were also suppressed by HF treatment in colon tissues, exhibiting a tissue-specific effect. To further reveal the metabolic signatures upon HF treatment, mass spectrometry-based metabolomic analysis of the small molecular metabolites in liver, spleen and colon tissues was performed. As a result, we found that HF treatment counteracted the levels of acylcarnitines, including palmitoyl-l-carnitine, isobutyrylcarnitine, vaccenylcarnitine, and myristoylcarnitine, in colon tissues with DSS induction, but no significant change in the levels of acylcarnitines was observed in liver or spleen tissues. The metabolic signatures may indicate that incomplete fatty acid oxidation (FAO) in the colon could be restored upon HF treatment as the tissue-specific metabolic characterization. Taken together, our findings uncovered that the HF potentiated anti-inflammatory effect in DSS-induced colitis in mice and its underlying mechanisms could be associated with the inhibition of HIF-1α and reduced levels of acylcarnitines, suggesting that both the inhibition of HIF-1α and the counteraction of incomplete FAO might be useful in the prevention and treatment of inflammatory bowel disease. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Biomarkers; Body Weight; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Energy Metabolism; Enzyme Activation; Fatty Acids; Gene Expression; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Inflammation Mediators; Liver; Male; Metabolic Networks and Pathways; Mice; Models, Biological; Oxidation-Reduction; Peroxidase; Phenotype; Piperidines; Quinazolinones; RNA, Messenger; Spleen | 2016 |
Anti-inflammatory activity of hydroalcoholic extracts of Lavandula dentata L. and Lavandula stoechas L.
Plants from genus Lavandula have been used as anti-inflammatory drugs in Mediterranean traditional medicine. Nowadays, there is a growing interest for complementary medicine, including herbal remedies, to treat inflammatory bowel disease (IBD).. To test the anti-inflammatory properties of Lavandula dentata and Lavandula stoechas extracts in two inflammatory experimental models: TNBS model of rat colitis and the carrageenan-induced paw edema in mice, in order to mimic the intestinal conditions and the extra-intestinal manifestations of human IBD, respectively.. The extracts were characterized through the qualitative HPLC analysis. Then, they were assayed in vitro and in vivo. In vitro studies were performed in BMDMs and CMT-93 epithelial cells with different concentrations of the extracts (ranging from 0.1 to 100µg/ml). The extracts were tested in vivo in the TNBS model of rat colitis (10 and 25mg/kg) and in the carrageenan-induced paw edema in mice (10, 25 and 100mg/kg).. L. dentata and L. stoechas extracts displayed immunomodulatory properties in vitro down-regulating different mediators of inflammation like cytokines and nitric oxide. They also showed anti-inflammatory effects in the TNBS model of colitis as evidenced by reduced myeloperoxidase activity and increased total glutathione content, indicating a decrease of neutrophil infiltration and an improvement of the oxidative state. Besides, both extracts modulated the expression of pro-inflammatory cytokines and chemokines, and ameliorated the altered epithelial barrier function. They also displayed anti-inflammatory effects in the carrageenan-induced paw edema in mice, since a significant reduction of the paw thickness was observed. This was associated with a down-regulation of the expression of different inducible enzymes like MMP-9, iNOS and COX-2 and pro-inflammatory cytokines, all involved in the maintenance of the inflammatory condition.. L. dentata and L. stoechas extracts showed intestinal anti-inflammatory effect, confirming their potential use as herbal remedies in gastrointestinal disorders. In addition, their anti-inflammatory effect was also observed in other locations, thus suggesting a possible use for the treatment of the extra-intestinal symptoms of IBD. Topics: Animals; Anti-Inflammatory Agents; Carrageenan; Cell Line; Chromatography, High Pressure Liquid; Chromatography, Reverse-Phase; Colitis; Cyclooxygenase 2; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Down-Regulation; Edema; Female; Glutathione; Inflammation Mediators; Lavandula; Matrix Metalloproteinase 9; Methanol; Mice, Inbred BALB C; Neutrophil Infiltration; Nitric Oxide; Nitric Oxide Synthase Type II; Oxidative Stress; Peroxidase; Phytotherapy; Plant Components, Aerial; Plant Extracts; Plants, Medicinal; Rats, Wistar; Solvents; Trinitrobenzenesulfonic Acid | 2016 |
Phosalone-induced inflammation and oxidative stress in the colon: Evaluation and treatment.
To investigate the side effects of phosalone on intestinal cells and to evaluate benefits of ellagic acid (EA) as a remedy.. In order to conduct an in vivo study, a rat model was used. The rats were divided into ten groups based on the materials used in the experiment and their dosage. The first group was fed normally. The second group was administered EA through gavage. Next Four groups were given (1/3, 1/5, 1/10, 1/20) LD50 phosalone; an organophosphorus compound. The last four groups received (1/3, 1/5, 1/10, 1/20) LD50 phosalone and of EA. After one month, the rats were sacrificed and their colon cells were examined to evaluate the level of inflammation, proteins and oxidative stress markers.. The results of this research show that phosalone elevates oxidative stress and changes the level of tumor necrosis factor-a (TNF-α), interlukin-6β (IL-6β) and nuclear factor (NF)-κB proteins. EA administration reduced phosalone toxicity and changed oxidative stress and inflammatory markers for all phosalone doses. Overall changes in reduction of TNF-α (230.47 ± 16.55 pg/mg protein vs 546.43 ± 45.24 pg/mg protein, P < 0.001), IL-6β (15.85 ± 1.03 pg/mg protein vs 21.55 ± 1.3 pg/mg protein, P < 0.05), and NF-κB (32.47 ± 4.85 pg/mg protein vs 51.41 ± 0.71 pg/mg protein, P < 0.05) manifest that the efficacy of EA is more viable for 1/3 LD50 dose of phosalone. Furthermore, EA is effective to counteract the negative outcomes of oxidative stress. When EA was used to treat 1/3 LD50 of phosalone's side effects, it improved the level of AChE activity (48.5% ± 6% vs 25% ± 7%, P < 0.05), TTM (0.391 ± 0.008 mmol/L vs 0.249 ± 0.032 mmol/L, P < 0.05), FRAP (46.04 ± 5.005 μmol/L vs 18.22 ± 1.9 μmol/L, P < 0.01) and MPO (0.222 ± 0.019 U/mg protein vs 0.387 ± 0.04 U/mg protein, P < 0.05).. This research highlights that EA is effective to alleviate the side effects of phosalone by reducing the level of oxidative stress and inflammatory proteins. Topics: Acetylcholinesterase; Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Colitis; Colon; Cytokines; Cytoprotection; Disease Models, Animal; Ellagic Acid; GPI-Linked Proteins; Inflammation Mediators; Lipid Peroxidation; Male; NF-kappa B; Organothiophosphorus Compounds; Oxidative Stress; Peroxidase; Rats, Wistar; Sulfhydryl Compounds; Thiobarbituric Acid Reactive Substances | 2016 |
Flaxseed extract exhibits mucosal protective effect in acetic acid induced colitis in mice by modulating cytokines, antioxidant and antiinflammatory mechanisms.
New treatments for inflammatory bowel disease are of interest due to high rate of remission failure. Natural products have been effective in IBD therapeutics as they have multiple constituents. The aim of the present study was to evaluate the effect of Flaxseed extract (Fs.Cr) on ulcerative colitis and identify the possible mechanisms involved. Colitis was induced by intrarectal administration of 6% AA in BALB/c mice. Colonic mucosal damage was assessed after 24h by calculating disease activity index (DAI), macroscopic and histological damage scores, biochemical measurement of myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total glutathione activities. Since cytokines are involved in exacerbating inflammatory cascade with emerging role of innate immune cytokines in IBD therapeutics, we hence assessed the effect on the levels of TNF-α, IFN-γ and IL-17, at 6, 12 and 24h by ELISA. Fs.Cr ameliorated the severity of AA colitis as evident by improved DAI, macroscopic damage and the histopathological scores along with restoration of goblet cells. Fs.Cr decreased MDA and MPO activities and enhanced antioxidant activity compared to the AA group. Finally, Fs.Cr in doses (300 and 500mg/kg) decreased TNF-α and IFN-γ levels at all time points with simultaneous increase in IL-17 levels at 24h as compared to the AA group. These results suggest that Fs.Cr ameliorates the severity of AA colitis by reducing goblet cell depletion, scavenging oxygen-derived free radicals, reduce neutrophil infiltration that may be attributed due to decreasing IFN-γ and TNF-α and increasing IL-17 levels. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Cell Movement; Colitis; Colon; Cytokines; Flax; Humans; Immunity, Mucosal; Inflammatory Bowel Diseases; Mice; Mice, Inbred BALB C; Neutrophils; Peroxidase; Plant Extracts | 2016 |
Mentha longifolia protects against acetic-acid induced colitis in rats.
Mentha longifolia L (Wild Mint or Habak) (ML) is used in traditional medicine in treatment of many gastrointestinal disorders.. This study aimed to evaluate potential protecting effect of ML and its major constituent, eucalyptol, against acetic acid-induced colitis in rats, a model of human inflammatory bowel disease (IBD).. Rats were divided into ten groups (n=8) given orally for three days (mg/kg/day) the following: normal control, acetic acid-induced colitis (un-treated, positive control), vehicle (DMSO), sulfasalazine (500), ML extract (100, 500, 1000), and eucalyptol (100, 200, 400). After 24h-fasting, two ML of acetic acid (3%) was administered intrarectally. On the fifth day, serum and colonic biochemical markers, and histopathological changes were evaluated.. Colitis significantly increased colonic myeloperoxidase activity and malonaldehyde level, and serum tumor necrosis factor-α, interleukin-6, and malonaldehyde levels while significantly decreased colonic and serum glutathione levels. All treatments (except ML 100, ML 1000, and eucalyptol 100) significantly reversed these changes where eucalyptol (400) showed the highest activity in a dose-dependent manner. The colitis-induced histopathological changes were mild in sulfasalazine and eucalyptol 400 groups, moderate in ML 500 and eucalyptol 200 groups, and severe in ML 100, ML 1000, and eucalyptol 100 groups nearly similar to colitis-untreated rats.. ML (in moderate doses) and eucalyptol (dose-dependently) exerted protective effects against acetic acid-induced colitis in rats possibly through antioxidant and antiinflammatory properties suggesting a potential benefit in treatments of IBD. To our knowledge this is the first report addressing this point. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Colitis; Colon; Cyclohexanols; Cytoprotection; Disease Models, Animal; Dose-Response Relationship, Drug; Eucalyptol; Gastrointestinal Agents; Glutathione; Interleukin-6; Male; Malondialdehyde; Mentha; Monoterpenes; Peroxidase; Phytotherapy; Plant Components, Aerial; Plant Extracts; Plants, Medicinal; Rats, Sprague-Dawley; Sulfasalazine; Time Factors; Tumor Necrosis Factor-alpha | 2016 |
Alpinetin attenuates inflammatory responses by suppressing TLR4 and NLRP3 signaling pathways in DSS-induced acute colitis.
Alpinetin, a composition of Alpinia katsumadai Hayata, has been reported to have a number of biological properties, such as antibacterial, antitumor and other important therapeutic activities. However, the effect of alpinetin on inflammatory bowel disease (IBD) has not yet been reported. The purpose of this study was to investigate the anti-inflammatory effect and mechanism of alpinetin on dextran sulfate sodium (DSS)-induced colitis in mice. In vivo, DSS-induced mice colitis model was established by giving mice drinking water containing 5% (w/v) DSS for 7 days. Alpinetin (25, 50 and 100 mg/kg) were administered once a day by intraperitoneal injection 3 days before DSS treatment. In vitro, phorbol myristate acetate (PMA)-differentiated monocytic THP-1 macrophages were treated with alpinetin and stimulated by lipopolysaccharide (LPS). The results showed that alpinetin significantly attenuated diarrhea, colonic shortening, histological injury, myeloperoxidase (MPO) activity and the expressions of tumor necrosis factor (TNF-α) and interleukin (IL-1β) production in mice. In vitro, alpinetin markedly inhibited LPS-induced TNF-α and IL-1β production, as well as Toll-like receptor 4 (TLR4) mediated nuclear transcription factor-kappaB (NF-κB) and NOD-like receptor protein 3 (NLRP3) inflammasome activation. In conclusion, this study demonstrated that alpinetin had protective effects on DSS-induced colitis and may be a promising therapeutic reagent for colitis treatment. Topics: Animals; Cell Survival; Colitis; Dextran Sulfate; Female; Flavanones; Humans; Inflammasomes; Inflammation; Injections, Intraperitoneal; Interleukin-1beta; Lipopolysaccharides; Macrophages; Mice; Mice, Inbred BALB C; NF-kappa B; NLR Family, Pyrin Domain-Containing 3 Protein; Peroxidase; Signal Transduction; Tetradecanoylphorbol Acetate; THP-1 Cells; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha | 2016 |
Role of the protein annexin A1 on the efficacy of anti-TNF treatment in a murine model of acute colitis.
TNF-α is involved in the mechanisms that initiate inflammatory bowel diseases (IBDs). Anti-TNF-α drugs, such as infliximab (IFX), cause non-responsiveness and side effects, indicating the need to investigate alternative therapies for these diseases. The anti-inflammatory protein, annexin A1 (AnxA1), has been associated with the protection of the gastrointestinal mucosa. To further address the role of endogenous AnxA1 on the TNF-α blockade efficacy in a murine model, we assessed colitis induced by Dextran Sulfate Sodium (DSS) in wild-type (WT) and AnxA1(-/-) Balb/c mice treated with IFX. We consistently observed endogenous AnxA1 prevented clinical and physiological manifestations of experimental colitis treated with IFX, additionally the manifestation of the disease was observed earlier in AnxA1(-)(/-) mice. Rectal bleeding, diarrhea, histological score, epithelial damages and collagen degradation caused by DSS were prevented following IFX treatment only in WT mice. IL-6 increased during colitis in WT and AnxA1(-)(/-) mice, decreasing under IFX treatment in WT. The influx of neutrophils and TNF-α secretion were largely elevated in AnxA1(-)(/-) mice when compared to WT mice. In the group WT/DSS+IFX, phagocytes were more susceptible to apoptosis following treatment with IFX. Endogenous expression of AnxA1 increased after DSS and decreased with IFX treatment, demonstrating an attenuated inflammatory response. The data indicate that AnxA1 contributes to the establishment of intestinal homeostasis after blocking of TNF-α was used as a treatment of IBD, constituting a key molecule in the mechanism of action and a potential biomarker of therapeutic efficacy. Topics: Animals; Annexin A1; Biomarkers; Caspase 3; Colitis; Dextran Sulfate; Female; Gastrointestinal Agents; Infliximab; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Peroxidase; Tumor Necrosis Factor-alpha | 2016 |
Rosmarinus officinalis L. extract ameliorates intestinal inflammation through MAPKs/NF-κB signaling in a murine model of acute experimental colitis.
We investigated the anti-inflammatory and anti-colitis effects of Rosmarinus officinalis L. extract (RE) by using both in vitro LPS-activated mouse RAW 264.7 macrophages and in vivo dextran sulfate sodium (DSS)-induced experimental murine colitis and suggested the underlying possible mechanisms. Liquid Chromatography-Mass Spectrometry (LC-MS) analysis was performed to identify the major components present in the RE. The clinical signs, biochemistry, immunoblot, ELISA and histology in colon tissues were assessed in order to elucidate the beneficial effect of RE. RE suppressed the LPS-induced pro-inflammatory cytokine production and the expressions of inflammatory proteins in macrophages. Administration of RE (50 and 100 mg kg(-1)) also significantly reduced the severity of DSS-induced murine colitis, as assessed by the clinical symptoms, colon length and histology. RE administration prevented the DSS-induced activation of p38, ERK and JNK MAPKs, attenuated IκBα phosphorylation and subsequent nuclear translocation and DNA binding of NF-κB (p65). RE also suppressed the COX-2 and iNOS expressions, decreased the levels of TNF-α and IL-6 cytokines and the myeloperoxidase activity in the colon tissue. Histological observation revealed that RE administration alleviated mucosal damage and inflammatory cell infiltration induced by DSS in the colon tissue. Hence, RE could be used as a new preventive and therapeutic food ingredient or as a dietary supplement for inflammatory bowel disease. Topics: Acute Disease; Animals; Colitis; Colon; Cyclooxygenase 2; Dextran Sulfate; Disease Models, Animal; DNA-Binding Proteins; Interleukin-6; Male; Mice; Mice, Inbred BALB C; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Phosphorylation; Plant Extracts; RAW 264.7 Cells; Rosmarinus; Signal Transduction; Tumor Necrosis Factor-alpha | 2016 |
Dietary Supplementation with a Low Dose of Polyphenol-Rich Grape Pomace Extract Prevents Dextran Sulfate Sodium-Induced Colitis in Rats.
Evidence from several epidemiological and experimental studies points to a beneficial role of dietary polyphenols in inflammatory bowel disease. In this study, we investigate the protective effect of dietary supplementation with various amounts of a polyphenol-rich grape pomace extract (GPE) on the development of dextran sulfate sodium (DSS)-induced colitis in rats. Rats were fed 21 days on a semisynthetic diet enriched with GPE (0.1%, 0.5%, and 1%), and acute colitis was induced by DSS (40 g/L in the drinking water) administration during the last 7 days. The low GPE content in the diet (0.1%) attenuated clinical signs and colon shortening and limited DSS-induced histological lesions. GPE 0.1% also attenuated the DSS-induced increase in myeloperoxidase activity and improved superoxide dismutase activity. Higher amounts of GPE in the diet induced only weak and nonsignificant protective effects. These results suggest that consumption of a low amount of polyphenol-rich GPE helps protect against colitis development. Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Dextran Sulfate; Dietary Supplements; Fruit; Inflammation; Inflammatory Bowel Diseases; Male; Peroxidase; Phytotherapy; Plant Extracts; Polyphenols; Rats, Wistar; Superoxide Dismutase; Vitis | 2016 |
Transplantation of a bacterial consortium ameliorates trinitrobenzenesulfonic acid-induced colitis and intestinal dysbiosis in rats.
To investigate the effects of a defined bacterial consortium on trinitrobenzenesulfonic acid (TNBS)-induced colitis and intestinal dysbiosis in rats.. Rats with TNBS-induced colitis were treated with ceftriaxone and/or a mixture of ten bacterial strains isolated from mouse feces for continuous 24 days. Macroscopic and histopathological parameters in colonic tissue were compared, as were myeloperoxidase enzyme activity and cytokine levels. Patterns of intestinal microbiota were assessed by PCR-denaturing gradient gel electrophoresis, the abundance of selected microbial groups was evaluated by qPCR.. Transplantation of the bacterial consortium showed anti-inflammatory activity in the intestines of rats with TNBS-induced colitis and contributed to the rapid re-establishment of intestinal microbial equilibrium. A defined bacterial consortium may be a viable therapeutic option for the treatment inflammatory bowel disease. Topics: Animals; Colitis; Colon; Cytokines; Disease Models, Animal; Dysbiosis; Fecal Microbiota Transplantation; Feces; Gastrointestinal Microbiome; Inflammatory Bowel Diseases; Intestines; Mice; Microbial Consortia; Peroxidase; Rats; Trinitrobenzenesulfonic Acid | 2016 |
Light-emitting diodes at 940nm attenuate colitis-induced inflammatory process in mice.
Inflammatory bowel disease (IBD) presents intense inflammatory infiltrate, crypt abscesses, ulceration and even loss of function. Despite the clinical relevance of IBD, its current therapy remains poorly effective. Infrared wavelength phototherapy shows therapeutic potential on inflammation. Our goal was to evaluate whether light-emitting diodes (LED) at 940nm are capable of mitigating the colitis-induced inflammatory process in mice. Forty male Swiss mice were assigned into five groups: control; control treated with LED therapy; colitis without treatment; colitis treated with LED therapy; colitis treated with Prednisolone. Experimental colitis was induced by acetic acid 7.5% (pH2.5) rectal administration. LED therapy was performed with light characterized by wavelength of 940nm, 45nm bandwidth, intensity of 4.05J/cm(2), total power of 270mW and total dose of 64.8J for 4min in a single application. Colitis-induced intestinal transit delay was inhibited by LED therapy. Colitis caused an increase of colon dimensions (length, diameter, total area) and colon weight (edema), which were inhibited by LED therapy. LED therapy also decreased colitis-induced tissue gross lesion, myeloperoxidase activity, microscopic tissue damage score and the presence of inflammatory infiltrate in all intestinal layers. Furthermore, LED therapy inhibited colitis-induced IL-1β, TNF-α, and IL-6 production. We conclude LED therapy at 940nm inhibited experimental colitis-induced colon inflammation in mice, therefore, rendering it a promising therapeutic approach that deserves further investigation. Topics: Animals; Colitis; Colon; Edema; Electrical Equipment and Supplies; Gastrointestinal Transit; Interleukin-1beta; Interleukin-6; Male; Mice; Peroxidase; Phototherapy; Tumor Necrosis Factor-alpha | 2016 |
Andrographolide derivative AL-1 ameliorates TNBS-induced colitis in mice: involvement of NF-кB and PPAR-γ signaling pathways.
Andrographolide is a traditional herb medicine, widely used in Asia for conditions involving inflammation. The andrographlide-lipoic acid conjugate, AL-1, has been found being able to alleviate inflammation in our previous reports. Although the anti-inflammatory activity of AL-1 contributes to its cytoprotective effects, whether AL-1 can improve inflammatory bowel disease (IBD) and the underlying mechanisms of its action remain largely unknown. In this study, we investigated the anti-inflammatory effects of AL-1 in C57BL/6 mice with trinitrobenzenesulfonic acid (TNBS)-induced colitis. The body weight loss and length change of colon after TNBS instillation were more severe than those in normal mice. AL-1 treatment led to significant reductions in disease activity index (DAI), macroscopic score and colon mucosa damage index (CMDI) associated with TNBS administration. AL-1 inhibited the inflammatory response via lowering the level of inflammatory cytokines and myeloperoxidase (MPO) activity. AL-1 attenuated the expression of p-p65, p-IκBα and COX-2 in the colitis mice. The alleviation of colon injury by AL-1 treatment was also evidenced by the increased expression of PPAR-γ. These results indicated that AL-1 could protect intestinal tract from the injury induced by TNBS in mice, suggesting that AL-1 may have potential in treatment for IBD. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Cytokines; Diterpenes; Inflammation Mediators; Mice, Inbred C57BL; NF-kappa B; Peroxidase; PPAR gamma; Signal Transduction; Thioctic Acid; Trinitrobenzenesulfonic Acid | 2016 |
Adeno-associated virus-mediated colonic secretory expression of HMGB1 A box attenuates experimental colitis in mice.
Extracellular high mobility group box 1 (HMGB1) is crucially implicated in the pathogenesis of inflammatory bowel diseases (IBDs). A box domain of HMGB1 has been identified as a specific antagonist of HMGB1. In the present study, we tested the effects of adeno-associated virus (AAV)-mediated colonic secretory expression of HMGB1 A box on murine experimental colitis.. Self-complementary AAV-2 carrying mouse immunoglobin Gκ leader-human HMGB1 A box (AAV-HMGB1 A box) was constructed. The effects of intracolonically administered AAV-HMGB1 A box on dextran sulfate sodium (DSS)- and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis were assessed by the disease activity index (DAI), colon length, macroscopic and histological scoring, myeloperoxidase (MPO) activity, and epithelial apoptosis and complementary proliferation. Colonic immune cell infiltrates, mucosal malondialdehyde content and superoxide dismutase activity, colonic tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-10 levels, serum HMGB1 concentration, and colonic HMGB1 release were determined to investigate the underlying mechanisms.. Intracolonically administered AAV-HMGB1 A box efficiently mediated secretory expression of HMGB1 A box and led to significant decreases in DAI, macroscopic and histological scores and colonic epithelial apoptosis in both DSS- and TNBS-treated mice. Modulating inflammation-associated cytokines, such as inhibiting colonic TNF-α and IL-1β expression, decreasing HMGB1 release, and restoring colonic IL-10 levels, and thereby inhibiting inflammatory cell infiltration and alleviating oxidant damage, might be the underlying mechanism.. Intracolonic application of AAV-HMGB1 A box is effective in alleviating murine colitis and has therapeutic potential in human IBDs. Topics: Animals; Apoptosis; Cell Proliferation; Colitis; Colon; Cytokines; Dependovirus; Dextran Sulfate; Epithelial Cells; HMGB1 Protein; Humans; Male; Mice, Inbred BALB C; Peroxidase; Superoxide Dismutase; Trinitrobenzenesulfonic Acid | 2016 |
LL202 protects against dextran sulfate sodium-induced experimental colitis in mice by inhibiting MAPK/AP-1 signaling.
LL202, a newly-synthesized flavonoid derivative, has been reported to inhibit inflammatory-induced angiogenesis. However, the exact role of LL202 in inflammation along with its mechanism has not been explored. In this study, we investigated the anti-inflammatory effect of LL202 on intestinal inflammation by establishing dextran sulfate sodium (DSS)-induced experimental colitis. LL202 attenuated DSS-induced body weight loss, colon length shortening and colonic pathological damage. The inflammatory cells infiltration, myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) activities were decreased by LL202 in a dose-dependent manner. LL202 reduced the production of pro-inflammatory cytokines in serum and colon of DSS-induced mice as well. Mechanically, LL202 could decrease the expression and nuclear translation of AP-1 to protect against DSS-induced colitis. In lipopolysaccharide (LPS)-induced THP-1 cells, LL202 markedly decreased the secretion, mRNA level and protein expression of IL-1β, IL-6 and TNF-α via inhibiting ERK/JNK/p38 MAPK pathways and the nuclear translocation of AP-1. Furthermore, these findings were confirmed in LPS-induced bone marrow derived macrophages (BMDM). In conclusion, our study demonstrated that LL202 could exert its anti-inflammatory effect via inhibiting MAPK/AP-1 signaling, which suggested that LL202 might be a potential effective drug for the treatment of inflammatory bowel diseases. Topics: Active Transport, Cell Nucleus; Animals; CD11b Antigen; Colitis; Cytokines; Dextran Sulfate; Female; Flavonoids; Gene Expression Regulation; Humans; Inflammation; Interleukin-1beta; Interleukin-6; Lipopolysaccharides; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Neovascularization, Pathologic; Nitric Oxide Synthase Type II; Peroxidase; RNA, Messenger; Signal Transduction; THP-1 Cells; Transcription Factor AP-1; Tumor Necrosis Factor-alpha | 2016 |
Partially hydrolysed guar gum ameliorates murine intestinal inflammation in association with modulating luminal microbiota and SCFA.
Partially hydrolysed guar gum (PHGG), a water-soluble dietary fibre produced by the controlled partial enzymatic hydrolysis of guar gum beans, has various physiological roles. This study aimed to elucidate the beneficial effects of PHGG on colonic mucosal damage in a murine 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis model. Acute colitis was induced in male C57BL/6 mice with TNBS after 2 weeks of pre-feeding with PHGG (5 %). The colonic mucosal inflammation was evaluated using macroscopic damage scores, and neutrophil infiltration was assessed by measuring tissue-associated myeloperoxidase (MPO) activity in the colonic mucosa. TNF-α expression in the colonic mucosa was measured by ELISA and real-time PCR. Moreover, the intestinal microbiota and production of SCFA were assessed by real-time PCR and HPLC, respectively. Colonic damage due to TNBS administration was significantly ameliorated by PHGG treatment. Furthermore, PHGG significantly inhibited increases in MPO activity and TNF-α protein and mRNA expression in the colonic mucosa in TNBS-induced colitis. On analysis of intestinal microbiota, we found that the concentration of the Clostridium coccoides group (Clostridium cluster XIVa), the Clostridium leptum subgroup (Clostridium cluster IV) and the Bacteroides fragilis group had significantly increased in PHGG-fed mice. On analysis of SCFA, we found that the caecal content of acetic acid, propionic acid and butyric acid had significantly increased in PHGG-fed mice. Together, these results suggest that chronic ingestion of PHGG prevents the development of TNBS-induced colitis in mice by modulating the intestinal microbiota and SCFA, which may be significant in the development of therapeutics for inflammatory bowel disease. Topics: Animals; Colitis; Colon; Disease Models, Animal; Fatty Acids, Volatile; Galactans; Gastrointestinal Microbiome; Hydrolysis; Inflammatory Bowel Diseases; Intestinal Mucosa; Intestines; Male; Mannans; Mice; Mice, Inbred C57BL; Peroxidase; Plant Gums; RNA, Messenger; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2016 |
Exaggerated IL-15 and Altered Expression of foxp3+ Cell-Derived Cytokines Contribute to Enhanced Colitis in Nlrp3-/- Mice.
The pathogenesis of Crohn's disease (CD) involves defects in the innate immune system, impairing responses to microbes. Studies have revealed that mutations NLRP3 are associated with CD. We reported previously that Nlrp3-/- mice were more susceptible to colitis and exhibited reduced colonic IL-10 expression. In the current study, we sought to determine how the loss of NLRP3 might be altering the function of regulatory T cells, a major source of IL-10. Colitis was induced in wild-type (WT) and Nlrp3-/- mice by treatment with dextran sulphate sodium (DSS). Lamina propria (LP) cells were assessed by flow cytometry and cytokine expression was assessed. DSS-treated Nlrp3-/- mice exhibited increased numbers of colonic foxp3+ T cells that expressed significantly lower levels of IL-10 but increased IL-17. This was associated with increased expression of colonic IL-15 and increased surface expression of IL-15 on LP dendritic cells. Neutralizing IL-15 in Nlrp3-/- mice attenuated the severity of colitis, decreased the number of colonic foxp3+ cells, and reduced the colonic expression of IL-12p40 and IL-17. These data suggest that the NLRP3 inflammasome can regulate intestinal inflammation through noncanonical mechanisms, providing additional insight as to how NLRP3 variants may contribute to the pathogenesis of CD. Topics: Animals; Colitis; Cytokines; Dendritic Cells; Flow Cytometry; Forkhead Transcription Factors; Inflammasomes; Interleukin-10; Interleukin-15; Interleukin-17; Male; Mice; Mice, Knockout; NLR Family, Pyrin Domain-Containing 3 Protein; Peroxidase | 2016 |
Adelmidrol, a Palmitoylethanolamide Analogue, as a New Pharmacological Treatment for the Management of Inflammatory Bowel Disease.
Leukocyte infiltration, improved levels of intercellular adhesion molecule 1 (ICAM-1), and oxidative stress in the colon are the principal factors in inflammatory bowel disease. The goal of the current study was to explore the effects of adelmidrol, an analog of the anti-inflammatory fatty acid amide signaling molecule palmitoylethanolamide, in mice subjected to experimental colitis. Additionally, to clarify whether the protective action of adelmidrol is dependent on the activation of peroxisome proliferator-activated receptors (PPARs), we investigated the effects of a PPARγ antagonist, GW9662, on adelmidrol action. Adelmidrol (10 mg/kg daily, o.s.) was tested in a murine experimental model of colitis induced by intracolonic administration of dinitrobenzene sulfonic acid. Nuclear factor-κB translocation, cyclooxygenase-2, and phosphoextracellular signal-regulated kinase, as well as tumor necrosis factor-α and interleukin-1β, were significantly increased in colon tissues after dinitrobenzene sulfonic acid administration. Immunohistochemical staining for ICAM-1, P-selectin, nitrotyrosine, and poly(ADP)ribose showed a positive staining in the inflamed colon. Treatment with adelmidrol decreased diarrhea, body weight loss, and myeloperoxidase activity. Adelmidrol treatment, moreover, reduced nuclear factor-κB translocation, cyclooxygenase-2, and phosphoextracellular signal-regulated kinase expression; proinflammatory cytokine release; and the incidence of nitrotyrosine and poly(ADP)ribose in the colon. It also decreased the upregulation of ICAM-1 and P-selectin. Adelmidrol treatment produced a reduction of Bax and an intensification of Bcl-2 expression. This study clearly demonstrates that adelmidrol exerts important anti-inflammatory effects that are partly dependent on PPARγ, suggesting that this molecule may represent a new pharmacologic approach for inflammatory bowel disease treatment. Topics: Amides; Animals; Anti-Inflammatory Agents; Apoptosis; Body Weight; Colitis; Cyclooxygenase 2; Cytokines; Dicarboxylic Acids; Dinitrofluorobenzene; Ethanolamines; Extracellular Signal-Regulated MAP Kinases; Inflammatory Bowel Diseases; Intercellular Adhesion Molecule-1; Lipid Peroxidation; Male; Mice; NF-kappa B; P-Selectin; Palmitic Acids; Peroxidase; Phosphorylation; PPAR alpha; PPAR gamma; Receptor, Cannabinoid, CB2; Signal Transduction; Tyrosine | 2016 |
Goat whey ameliorates intestinal inflammation on acetic acid-induced colitis in rats.
Complementary or alternative medicine is of great interest for the treatment of inflammatory bowel disease, with the aim of ameliorating the side effects of the drugs commonly used or improving their efficacy. In this study, we evaluated the ability of goat whey to prevent intestinal inflammation in the experimental model of acetic acid-induced rats and compared it to sulfasalazine. Pretreatment with goat whey (1, 2, and 4g/kg) and sulfasalazine (250mg/kg) on colitic rats improved colonic inflammatory markers, including myeloperoxidase activity, leukotriene B Topics: Acetic Acid; Animals; Colitis; Colon; Goats; Humans; Inflammation; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Whey | 2016 |
Anti-inflammatory effect of cannabinoid agonist WIN55, 212 on mouse experimental colitis is related to inhibition of p38MAPK.
To investigate the anti-inflammatory effect and the possible mechanisms of an agonist of cannabinoid (CB) receptors, WIN55-212-2 (WIN55), in mice with experimental colitis, so as to supply experimental evidence for its clinical use in future.. We established the colitis model in C57BL/6 mice by replacing the animals' water supply with 4% dextran sulfate sodium (DSS) for 7 consecutive days. A colitis scoring system was used to evaluate the severity of colon local lesion. The plasma levels of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), and the myeloperoxidase (MPO) activity in colon tissue were measured. The expressions of cannabinoid receptors, claudin-1 protein, p38 mitogen-activated protein kinase (p38MAPK) and its phosphorylated form (p-p38) in colon tissue were determined by immunohistochemistry and Western blot. In addition, the effect of SB203580 (SB), an inhibitor of p38, was investigated in parallel experiments, and the data were compared with those from intervention groups of WIN55 and SB alone or used together.. The results demonstrated that WIN55 or SB treatment alone or together improved the pathological changes in mice with DSS colitis, decreased the plasma levels of TNF-α, and IL-6, and MPO activity in colon. The enhanced expression of claudin-1 and the inhibited expression of p-p38 in colon tissues were found in the WIN55-treated group. Besides, the expression of CB1 and CB2 receptors was enhanced in the colon after the induction of DSS colitis, but reduced when p38MAPK was inhibited.. These results confirmed the anti-inflammatory effect and protective role of WIN55 on the mice with experimental colitis, and revealed that this agent exercises its action at least partially by inhibiting p38MAPK. Furthermore, the results showed that SB203580, affected the expression of CB1 and CB2 receptors in the mouse colon, suggesting a close linkage and cross-talk between the p38MAPK signaling pathway and the endogenous CB system. Topics: Animals; Anti-Inflammatory Agents; Benzoxazines; Cannabinoid Receptor Agonists; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Female; Imidazoles; Interleukin-6; Male; Mice, Inbred C57BL; Morpholines; Naphthalenes; p38 Mitogen-Activated Protein Kinases; Peroxidase; Protein Kinase Inhibitors; Pyridines; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Signal Transduction; Tumor Necrosis Factor-alpha | 2016 |
Palmitoylethanolamide, a naturally occurring lipid, is an orally effective intestinal anti-inflammatory agent.
Palmitoylethanolamide (PEA) acts via several targets, including cannabinoid CB1 and CB2 receptors, transient receptor potential vanilloid type-1 (TRPV1) ion channels, peroxisome proliferator-activated receptor alpha (PPAR α) and orphan G protein-coupled receptor 55 (GRR55), all involved in the control of intestinal inflammation. Here, we investigated the effect of PEA in a murine model of colitis.. Colitis was induced in mice by intracolonic administration of dinitrobenzenesulfonic acid (DNBS). Inflammation was assessed by evaluating inflammatory markers/parameters and by histology; intestinal permeability by a fluorescent method; colonic cell proliferation by immunohistochemistry; PEA and endocannabinoid levels by liquid chromatography mass spectrometry; receptor and enzyme mRNA expression by quantitative RT-PCR.. DNBS administration caused inflammatory damage, increased colonic levels of PEA and endocannabinoids, down-regulation of mRNA for TRPV1 and GPR55 but no changes in mRNA for CB1 , CB2 and PPARα. Exogenous PEA (i.p. and/or p.o., 1 mg·kg(-1) ) attenuated inflammation and intestinal permeability, stimulated colonic cell proliferation, and increased colonic TRPV1 and CB1 receptor expression. The anti-inflammatory effect of PEA was attenuated or abolished by CB2 receptor, GPR55 or PPARα antagonists and further increased by the TRPV1 antagonist capsazepine.. PEA improves murine experimental colitis, the effect being mediated by CB2 receptors, GPR55 and PPARα, and modulated by TRPV1 channels. Topics: Administration, Oral; Amides; Animals; Anti-Inflammatory Agents; Benzenesulfonates; Capsaicin; Colitis; Colon; Disease Models, Animal; Endocannabinoids; Ethanolamines; Intestinal Absorption; Male; Mice, Inbred ICR; Oleic Acids; Palmitic Acids; Peroxidase; PPAR alpha; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Receptors, Cannabinoid; RNA, Messenger; TRPV Cation Channels | 2015 |
Vasoactive intestinal peptide-deficient mice exhibit reduced pathology in trinitrobenzene sulfonic acid-induced colitis.
Vasoactive intestinal peptide (VIP) is an immunomodulatory neuropeptide with therapeutic properties in multiple murine models of inflammatory disease including the trinitrobenzene-sulfonic acid (TNBS)-colitis model of Crohn's disease. Understanding the spectrum of biological actions of endogenously produced VIP may help us dissect the complex and multifactorial pathogenesis of such inflammatory diseases. Our goal was to determine the contribution of endogenously produced VIP to TNBS-colitis by using VIP knockout (KO) mice.. TNBS was intracolonically administered to wild-type (WT) and VIP KO mice, and weight loss and colitis were assessed over time. Colon histopathological changes and myeloperoxidase activities were analyzed and the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in colon and serum quantified. The proliferative response in vitro of splenocytes from TNBS WT and VIP KO administered mice to anti-CD3 and anti-CD28 was determined.. VIP KO mice did not exhibit the predicted exacerbated response to TNBS. Instead, they developed a milder clinical profile than WT mice, with lower TNF-α and IL-6 levels. Such potential defects seem selective, because other parameters such as the histopathological scores and the cytokine levels in the colon did not differ between the two strains of mice. Moreover, splenocytes from TNBS-treated VIP KO mice exhibited an enhanced proliferative response to anti-CD3/CD28 stimulation in vitro.. Chronic loss of VIP in mice leads to a disruption of certain but not all immunological compartments, corroborating recent findings that VIP KO mice exhibit reduced mortality in the lipopolysaccharide-induced endotoxemia model and attenuated clinical development of experimental autoimmune encephalomyelitis while developing robust T-cell responses. Topics: Animals; Cell Proliferation; Colitis; Colon; Cytokines; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Gene Expression Regulation; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; RNA, Messenger; T-Lymphocytes; Time Factors; Trinitrobenzenesulfonic Acid; Vasoactive Intestinal Peptide | 2015 |
N-Acylethanolamine-hydrolyzing acid amidase inhibition increases colon N-palmitoylethanolamine levels and counteracts murine colitis.
N-Palmitoylethanolamine or palmitoylethanolamide (PEA) is an anti-inflammatory compound that was recently shown to exert peroxisome proliferator-activated receptor-α-dependent beneficial effects on colon inflammation. The actions of PEA are terminated following hydrolysis by 2 enzymes: fatty acid amide hydrolase (FAAH), and the less-studied N-acylethanolamine-hydrolyzing acid amidase (NAAA). This study aims to investigate the effects of inhibiting the enzymes responsible for PEA hydrolysis in colon inflammation in order to propose a potential therapeutic target for inflammatory bowel diseases (IBDs). Two murine models of IBD were used to assess the effects of NAAA inhibition, FAAH inhibition, and PEA on macroscopic signs of colon inflammation, macrophage/neutrophil infiltration, and the expression of proinflammatory mediators in the colon, as well as on the colitis-related systemic inflammation. NAAA inhibition increases PEA levels in the colon and reduces colon inflammation and systemic inflammation, similarly to PEA. FAAH inhibition, however, does not increase PEA levels in the colon and does not affect the macroscopic signs of colon inflammation or immune cell infiltration. This is the first report of an anti-inflammatory effect of a systemically administered NAAA inhibitor. Because NAAA is the enzyme responsible for the control of PEA levels in the colon, we put forth this enzyme as a potential therapeutic target in chronic inflammation in general and IBD in particular. Topics: Amides; Amidohydrolases; Animals; Anti-Inflammatory Agents; Arachidonic Acids; Chromatography, High Pressure Liquid; Colitis; Colon; Cytokines; Disease Models, Animal; Endocannabinoids; Enzyme-Linked Immunosorbent Assay; Ethanolamines; Gene Expression Regulation; Glycerides; Inflammation; Inflammatory Bowel Diseases; Male; Mice; Mice, Inbred C57BL; Neutrophils; Palmitic Acids; Peroxidase; Piperidines; Pyridines; Taurine | 2015 |
Impact of basal diet on dextran sodium sulphate (DSS)-induced colitis in rats.
Dextran sodium sulphate (DSS)-induced colitis is a widely used model for inflammatory bowel disease. However, various factors including nutrition may affect the development of this colitis. This study aimed to compare and characterize the impact of purified and non-purified basal diets on the development of DSS-induced colitis in the rat.. Wistar rats were fed a non-purified or a semi-synthetic purified diet for 21 days. Colitis was then induced in half of the rats by administration of DSS in drinking water (4% w/v) during the last 7 days of experimentation. At the end of the experimental period, colon sections were taken for histopathological examination, determination of various markers of inflammation (myeloperoxidase: MPO, cytokines) and oxidative stress (superoxide dismutase: SOD, catalase: CAT, glutathione peroxidase: GPx and glutathione reductase: GRed activities), and evaluation of the expression of various genes implicated in this disorder.. DSS ingestion induced a more marked colitis in animals receiving the purified diet, as reflected by higher histological score and increased MPO activity. A significant decrease in SOD and CAT activities was also observed in rats fed the purified diet. Also, in these animals, administration of DSS induced a significant increase in interleukin (IL)-1α, IL-1β and IL-6. In addition, various genes implicated in inflammation were over-expressed after ingestion of DSS by rats fed the purified diet.. These results show that a purified diet promotes the onset of a more severe induced colitis than a non-purified one, highlighting the influence of basal diet in colitis development. Topics: Animals; Antioxidants; Body Weight; Catalase; Colitis; Colon; Cytokines; Dextran Sulfate; Diet; Disease Models, Animal; Energy Intake; Glutathione Peroxidase; Glutathione Reductase; Inflammation; Interleukin-1alpha; Interleukin-1beta; Interleukin-6; Male; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Superoxide Dismutase; Up-Regulation | 2015 |
Gelling polysaccharide from Chondrus armatus and its oligosaccharides: the structural peculiarities and anti-inflammatory activity.
Structural peculiarities of low molecular weight (LMW) sample obtained by mild acid hydrolysis of κ-carrageenan from Chondrus armatus was investigated by a rapid mass spectrometric method. The selected conditions allowed avoiding excess destruction of 3,6-AnGal residues that was shown by using tandem (MS/MS) mode. Main oligosaccharide fraction with molecular weight 2.3 kg/mol, obtained by mild acid hydrolysis was chosen for the analysis. It was shown that fragments with even degree of polymerization (DP) were mostly built of (-G4S-DA-)n repeating unit, n=1-5. Some fragments with odd DP were shown to contain -DA2S- insertions, being the fragments of ι-type blocks, which were randomly distributed along the polysaccharide chain as single insertions. The anti-inflammatory activity (on acetic acid-induced colitis in mice) of the initial polymer and its derivatives was studied. The anti-inflammatory effect of the polymer was observed at a dose of 5mg/kg. Polysaccharide decreased the degree of colon damage more than twice and area of damage in 40%. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Carrageenan; Chondrus; Colitis; Colon; Gels; Hydrolysis; Male; Mice; Molecular Weight; Oligosaccharides; Peroxidase; Tandem Mass Spectrometry | 2015 |
Pelvic organ cross-sensitization to enhance bladder and urethral pain behaviors in rats with experimental colitis.
Neural cross-sensitization has been postulated as a mechanism underlying overlaps of chronic pelvic pain disorders such as bladder pain syndrome/interstitial cystitis (BPS/IC) and irritable bowel syndrome (IBS). Animals with experimental colitis have been used to study the underlying mechanisms for overlapped pelvic pain symptoms, and shown to exhibit bladder overactivity evidenced by frequent voiding; however, it has not directly been evaluated whether pain sensation derived from the lower urinary tract is enhanced in colitis models. Also, the cross-sensitization between the colon and urethra has not been studied previously. In the present study, we therefore investigated pain behaviors induced by nociceptive stimuli in the lower urinary tract and the involvement of C-fiber afferent pathways using rats with colitis induced by intracolonic application of 2,4,6-trinitrobenzenesulfonic acid (TNBS). In TNBS-induced colitis rats at 10 days, intravesical application of resiniferatoxin (RTx) induced a significantly greater number of episodes of both licking and freezing behaviors, which were reduced by capsaicin-sensitive C-fiber afferent desensitization. Histochemical studies using fluorescent dye tracers injected into the colon, bladder or urethra showed that dichotomized afferent neurons comprised 6.9-14.5% of L1, L6 and S1 dorsal root ganglion (DRG) neurons innervating the colon or the lower urinary tract. Transient receptor potential vanilloid 1 (TRPV1) mRNA expression was significantly increased in, the bladder, urethra and S1 DRG in colitis rats. An increase in myeloperoxidase (MPO) activity was found in the colon, but not in the bladder or urethra after intracolonic TNBS treatment. These results indicate that TNBS-induced colitis increased pain sensitivity in the bladder and urethra via activation of C-fiber afferent pathways due to colon-to-bladder and colon-to-urethral cross-sensitization, suggesting the contribution of pelvic organ cross-sensitization mechanisms to overlapped pain symptoms in BPS/IC and IBS. Topics: Animals; Colitis; Colon; Disease Models, Animal; Diterpenes; Female; Freezing Reaction, Cataleptic; Ganglia, Spinal; Grooming; Neurons, Afferent; Pain; Peroxidase; Rats, Sprague-Dawley; RNA, Messenger; Trinitrobenzenesulfonic Acid; TRPV Cation Channels; Urethra; Urinary Bladder | 2015 |
In vivo efficacy of microbiota-sensitive coatings for colon targeting: a promising tool for IBD therapy.
The first proof of concept in vivo for a new type of microbiota-sensitive film coatings allowing for colon targeting is presented. The efficacy of these polysaccharide barriers to optimize drug release for the treatment of inflammation is demonstrated in an experimental colitis model with Wister rats. 5-Aminosalicylic acid (5-ASA) pellets were prepared by extrusion-spheronization and coated with Nutriose:ethylcellulose (EC) 1:4 or peas starch:ethylcellulose 1:2 blends. The pellets were mixed with standard chow, and the daily drug dose was 150mg/kg. For reasons of comparison, also commercially available Pentasa pellets and placebo pellets were studied. At day 3 after the beginning of the treatment, colitis was induced by intrarectal administration of trinitrobenzene sulfonic acid (TNBS). Animals were sacrificed on day 6. Macroscopic and histological evaluations of colitis were performed blindly. In addition, inflammatory markers were evaluated using ELISA and real-time PCR. Rats receiving TNBS and placebo pellets developed a severe colitis in the distal half of the colon. 5-ASA administered in the form of Pentasa pellets reduced macroscopic inflammation by only 5%. In contrast, the colon lesions were much less severe upon treatment with Nutriose:EC- and peas starch:EC-coated pellets: The macroscopic score was reduced by 25 and 24%, respectively. Decreases of 37 and 38% of the histological lesions confirmed the efficacy of these new colon targeting systems. Also, inflammatory markers (MPO, IL-1β mRNA, TNF mRNA) were significantly decreased in rats receiving Nutriose:EC- and peas starch:EC-coated pellets compared to Pentasa pellets. Furthermore, real-time PCR analysis indicated increased activation of the target receptor PPAR-γ and the HMGCS2 gene in rats upon administration of 5-ASA loaded Nutriose:EC- and peas starch:EC pellets compared to the commercial product. Also, HPLC-MS/MS analysis of plasma samples demonstrated that the level of the main metabolite of the drug (N-acetyl-5-ASA) was much lower upon administration of Nutriose:EC or peas starch:EC coated pellets compared to Pentasa pellets, indicating that undesired premature drug release in the upper gastrointestinal tract was more effectively hindered. In addition to the rat study, in vivo imaging of transgenic mice expressing the luciferase gene evidenced much more pronounced PPAR-γ activation upon 5-ASA administration in the form of Nutriose:EC-coated pellets versus Pentasa pellets. All these resul Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Cellulose; Colitis; Colon; Dextrins; Drug Delivery Systems; Hydroxymethylglutaryl-CoA Synthase; Interleukin-1beta; Male; Mesalamine; Mice, Transgenic; Microbiota; Peroxidase; PPAR gamma; Rats, Wistar; RNA, Messenger; Starch; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2015 |
The anti-inflammatory and antioxidant effects of bergamot juice extract (BJe) in an experimental model of inflammatory bowel disease.
The beneficial properties of the flavonoid fraction of bergamot juice (BJe) have been raising interest and have been the subject of recent studies, considering the potentiality of its health promoting substances. Flavonoids have demonstrated radical-scavenging and anti-inflammatory activities. The aim of the present study was to examine the effects of BJe in mice subjected to experimental colitis.. Colitis was induced in mice by intracolonic instillation of dinitrobenzene sulfonic acid (DNBS). BJe was administered daily orally (at 5, 10 and 20 mg/kg).. Four days after DNBS administration, colon nuclear factor NF-κB translocation and MAP kinase phospho-JNK activation were increased as well as cytokine production such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β. Neutrophil infiltration, by myeloperoxidase (MPO) activity, in the mucosa was associated with up-regulation of adhesion molecules (ICAM-1 and P-selectin). Immunohistochemistry for nitrotyrosine and poly ADP-ribose (PAR) also showed an intense staining in the inflamed colon. Treatment with BJe decreased the appearance of diarrhea and body weight loss. This was associated with a reduction in colonic MPO activity. BJe reduced nuclear NF-κB translocation, p-JNK activation, the pro-inflammatory cytokines release, the appearance of nitrotyrosine and PAR in the colon and reduced the up-regulation of ICAM-1 and P-selectin. In addition, colon inflammation was also associated with apoptotic damage. Treatment with BJe caused a decrease of pro-apoptotic Bax expression and an increase of anti-apoptotic Bcl-2 expression.. The results of this study suggested that administration of BJe induced, partly specified, anti-inflammatory mechanisms, which potentially may be beneficial for the treatment of IBD in humans. Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; bcl-2-Associated X Protein; Benzenesulfonates; Beverages; Citrus; Colitis; Colon; Disease Models, Animal; Inflammatory Bowel Diseases; Intercellular Adhesion Molecule-1; Interleukin-1beta; Male; Mice; Neutrophil Infiltration; NF-kappa B; P-Selectin; Peroxidase; Plant Extracts; Poly Adenosine Diphosphate Ribose; Tumor Necrosis Factor-alpha; Tyrosine; Up-Regulation | 2015 |
Lactosucrose attenuates intestinal inflammation by promoting Th2 cytokine production and enhancing CD86 expression in colitic rats.
Some oligosaccharides have immunoregulatory and anti-inflammatory functions in the intestine. This study investigated the immunoregulatory effect of lactosucrose (LS) on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitic rats. Alkaline phosphatase activity was increased but myeloperoxidase activity was decreased in the LS-TNBS group, as compared with the TNBS group (colitis rats without receiving LS). LS supplementation stimulated IL-4 and IL-10 production, while up-regulating CD86 expression in dendritic cells. LS supplementation reduced the ratio of CD80/CD86 and the ratio of IFN-γ/IL-4 compared to the TNBS group. Moreover, IFN-γ was significantly correlated with CD80 (r = 0.764, p < 0.01), whereas IL-4 was significantly correlated with CD86 (r = 0.489, p < 0.05). These results indicated that LS attenuated colitis by promoting the production of Th2-type cytokines and rebalancing the ratio of Th1/Th2 and that enhanced IL-4 production is correlated with enhanced CD86 expression in the gut. Therefore, LS is a functional food for patients with inflammatory bowel disease. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents, Non-Steroidal; B7-1 Antigen; B7-2 Antigen; Colitis; Colon; Dendritic Cells; Female; Gene Expression Regulation; Inflammation; Interferon-gamma; Interleukin-10; Interleukin-4; Intestinal Mucosa; Peroxidase; Rats; Rats, Sprague-Dawley; Severity of Illness Index; Th1-Th2 Balance; Trinitrobenzenesulfonic Acid; Trisaccharides | 2015 |
Eudragit nanoparticles loaded with silybin: a detailed study of preparation, freeze-drying condition and in vitro/in vivo evaluation.
The objective of this work was use of silybin nanoparticles in treatment of ulcerative colitis (UC). Eudragit RL PO nanoparticles loaded with silybin were produced using solvent-evaporation emulsification technique. Then, they were coated by Eudragit FS30D. Drug release was studied in different physiological environments. Colitis was induced by 4% of acetic acid in rats which received freeze-dried nanoparticles of silybin (75 mg/kg/day), dexamethasone (1 mg/kg/day), blank nanoparticles and normal saline orally for 5 days. Then macroscopic, histopathological evaluation and biochemical analysis, including myeloperoxidase (MPO) activity, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels in colon tissues were determined using enzyme-linked immunosorbent assay (ELISA) kits. Macroscopic and histopathological scores were improved by the optimised nanoparticles. The optimised nanoparticles had a particle size of 109 ± 6 nm, zeta potential of 15.4 ± 2 mV, loading efficiency of 98.3 ± 12% and release efficiency of 40.8 ± 5.5% at 24 h. TNF-α, IL-6 and MPO activity were reduced significantly by nanoparticles compared to control group (p < 0.05). Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Colon; Dexamethasone; Drug Carriers; Freeze Drying; Inflammation; Interleukin-6; Male; Nanoparticles; Peroxidase; Polymethacrylic Acids; Rats, Wistar; Silybin; Silybum marianum; Silymarin; Tumor Necrosis Factor-alpha | 2015 |
Altered vasoactive intestinal peptides expression in irritable bowel syndrome patients and rats with trinitrobenzene sulfonic acid-induced colitis.
To investigate the vasoactive intestinal peptides (VIP) expression in irritable bowel syndrome (IBS) and trinitrobenzene sulfonic acid (TNBS) induced colitis.. The VIP gene expression and protein plasma levels were measured in adult participants (45.8% male) who met Rome III criteria for IBS for longer than 6 mo and in a rat model of colitis as induced by TNBS. Plasma and colons were collected from naïve and inflamed rats. Markers assessing inflammation (i.e., weight changes and myeloperoxidase levels) were assessed on days 2, 7, 14 and 28 and compared to controls. Visceral hypersensitivity of the rats was assessed with colo-rectal distension and mechanical threshold testing on hind paws. IBS patients (n = 12) were age, gender, race, and BMI-matched with healthy controls (n = 12). Peripheral whole blood and plasma from fasting participants was collected and VIP plasma levels were assayed using a VIP peptide-enzyme immunoassay. Human gene expression of VIP was analyzed using a custom PCR array.. TNBS induced colitis in the rats was confirmed with weight loss (13.7 ± 3.2 g) and increased myeloperoxidase activity. Visceral hypersensitivity to colo-rectal distension was increased in TNBS treated rats up to 21 d and resolved by day 28. Somatic hypersensitivity was also increased up to 14 d post TNBS induction of colitis. The expression of an inflammatory marker myeloperoxidase was significantly elevated in the intracellular granules of neutrophils in rat models following TNBS treatment compared to naïve rats. This confirmed the induction of inflammation in rats following TNBS treatment. VIP plasma concentration was significantly increased in rats following TNBS treatment as compared to naïve animals (P < 0.05). Likewise, the VIP gene expression from peripheral whole blood was significantly upregulated by 2.91-fold in IBS patients when compared to controls (P < 0.00001; 95%CI). VIP plasma protein was not significantly different when compared with controls (P = 0.193).. Alterations in VIP expression may play a role in IBS. Therefore, a better understanding of the physiology of VIP could lead to new therapeutics. Topics: Adult; Animals; Biomarkers; Case-Control Studies; Colitis; Colon; Disease Models, Animal; Female; Gene Expression Regulation; Humans; Hyperalgesia; Inflammation Mediators; Irritable Bowel Syndrome; Male; Middle Aged; Pain Threshold; Peroxidase; Pilot Projects; Rats, Sprague-Dawley; RNA, Messenger; Signal Transduction; Time Factors; Trinitrobenzenesulfonic Acid; Vasoactive Intestinal Peptide; Visceral Pain; Weight Loss; Young Adult | 2015 |
Ghrelin ameliorates intestinal barrier dysfunction in experimental colitis by inhibiting the activation of nuclear factor-kappa B.
This study aimed to investigate the effect and underlying mechanism of ghrelin on intestinal barrier dysfunction in dextran sulfate sodium (DSS)-induced colitis.. Acute colitis was induced in C57BL/6J mice by administering 2.5% DSS. Saline or 25, 125, 250 μg/kg ghrelin was administrated intraperitoneally (IP) to mice 1 day before colitis induction and on days 4, 5, and 6 after DSS administration. IP injection of a ghrelin receptor antagonist, [D-lys(3)]-GHRP-6, was performed immediately prior to ghrelin injection. Ghrelin (125 or 250 μg/kg) could reduce the disease activity index, histological score, and myeloperoxidase activities in experimental colitis, and also prevented shortening of the colon. Ghrelin could prevent the reduction of transepithelial electrical resistance and tight junction expression, and bolstered tight junction structural integrity and regulated cytokine secretion. Ultimately, ghrelin inhibited nuclear factor kappa B (NF-κB), inhibitory κB-α, myosin light chain kinase, and phosphorylated myosin light chain 2 activation.. Ghrelin prevented the breakdown of intestinal barrier function in DSS-induced colitis. The protective effects of ghrelin on intestinal barrier function were mediated by its receptor GHSR-1a. The inhibition of NF-κB activation might be part of the mechanism underlying the effects of ghrelin that protect against barrier dysfunction. Topics: Animals; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Ghrelin; Intestinal Mucosa; Intestines; Male; Mice, Inbred C57BL; Myosin-Light-Chain Kinase; NF-kappa B; Oligopeptides; Peroxidase; Receptors, Ghrelin; Tight Junctions | 2015 |
Timosaponin AIII and its metabolite sarsasapogenin ameliorate colitis in mice by inhibiting NF-κB and MAPK activation and restoring Th17/Treg cell balance.
The rhizome of Anemarrhena asphodeloides (AA, family Liliaceae), which contains furostanol and spirostanol saponins, is a typical herbal medicine that improves learning and memory in rats and inhibits inflammation. In a preliminary study, timosaponin AIII, one of AA main constituents, was metabolized to sarsasapogenin by gut microbiota and inhibited NF-κB activation in lipopolysaccharide (LPS)-stimulated macrophages. Here we have investigated the anti-inflammatory effects of AIII and sarsasapogenin in vitro and in vivo. Both AIII and sarsasapogenin potently inhibited NF-κB and MAPK activation, as well as IRAK1, TAK1, and IκBα phosphorylation in LPS-stimulated macrophages. Further, AIII and sarsasapogenin inhibited the binding of LPS to macrophage Toll-like receptor 4, as well as polarization of M2 to M1 macrophages. Oral administration of AIII and sarsasapogenin inhibited 2,3,4-trinitrobenzene sulfonic acid (TNBS)-induced colon shortening and myeloperoxidase activity in mice, along with reducing NF-κB activation and interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and IL-6 levels, while simultaneously increasing IL-10. Both compounds inhibited Th17 cell differentiation in colonic lamina propria, but induced Treg cell differentiation. Further, AIII and sarsasapogenin inhibited the differentiation of splenic CD4(+) T cells into Th17 cells in vitro. The vitro and in vivo anti-inflammatory effects of sarsasapogenin were more potent than AIII. These results suggest that orally administered AIII may be metabolized to sarsasapogenin by gut microbiota, which may ameliorate inflammatory diseases such as colitis by inhibiting TLR4-NF-κB/MAPK signaling pathway and restoring Th17/Treg cell balance. Topics: Animals; Anti-Inflammatory Agents; Cell Differentiation; Cells, Cultured; Colitis; Colon; Lipopolysaccharides; Macrophages, Peritoneal; Male; Mice, Inbred C57BL; Mitogen-Activated Protein Kinases; NF-kappa B; Peroxidase; Saponins; Spirostans; Steroids; T-Lymphocytes, Regulatory; Th17 Cells; Trinitrobenzenesulfonic Acid | 2015 |
Effects of dietary virgin olive oil polyphenols: hydroxytyrosyl acetate and 3, 4-dihydroxyphenylglycol on DSS-induced acute colitis in mice.
Hydroxytyrosol, a polyphenolic compound from extra virgin olive oil (EVOO) has exhibited an improvement in a model of DSS-induced colitis. However, other phenolic compounds present such as hydroxytyrosyl acetate (HTy-Ac) and 3,4-dihydroxyphenylglycol (DHPG) need to be explored to complete the understanding of the overall effects of EVOO on inflammatory colon mucosa. This study was designed to evaluate the effect of both HTy-Ac and DHPG dietary supplementation in the inflammatory response associated to colitis model. Six-week-old mice were randomized in four dietary groups: sham and control groups received standard diet, and other two groups were fed with HTy-Ac and DHPG, respectively, at 0.1%. After 30 days, all groups except sham received 3% DSS in drinking water for 5 days followed by a regime of 5 days of water. Acute inflammation was evaluated by Disease Activity Index (DAI), histology and myeloperoxidase (MPO) activity. Colonic expression of iNOS, COX-2, MAPKs, NF-kB and FOXP3 were determined by western blotting. Only HTy-Ac-supplemented group showed a significant DAI reduction as well as an improvement of histological damage and MPO. COX-2 and iNOS protein expression were also significantly reduced. In addition, this dietary group down-regulated JNK phosphorylation and prevented the DSS-induced nuclear translocation level of p65. However, no significant differences were observed in the FOXP3 expression. These results demonstrated, for the first time, that HTy-Ac exerts an antiinflammatory effect on acute ulcerative colitis. We concluded that HTy-Ac supplement might provide a basis for developing a new dietary strategy for the prevention of ulcerative colitis. Topics: Acetates; Animals; Catechols; Colitis; Cyclooxygenase 2; Dextran Sulfate; Female; MAP Kinase Signaling System; Methoxyhydroxyphenylglycol; Mice; Mice, Inbred C57BL; NF-kappa B; Nitric Oxide Synthase Type II; Olive Oil; Peroxidase | 2015 |
Experimental colitis in mice is attenuated by topical administration of chlorogenic acid.
Epidemiological data suggest that the consumption of polyphenol-rich foods reduces the incidence of cancer, coronary heart disease, and inflammation. Chlorogenic acid (CGA), an ester of caffeic and quinic acids, is one of the most abundant polyphenol compounds in human diet with proven biological effectiveness both in vitro and in vivo. The aim of the study is to investigate the possible anti-inflammatory effect of CGA in the gastrointestinal (GI) tract and its mechanism of action. We used a well-established model of colitis, induced by intracolonic (i.c.) administration of trinitrobenzenesulfonic acid (TNBS) in mice. The anti-inflammatory effect of CGA in the colon was evaluated based on the clinical and macroscopic and microscopic parameters. To investigate the mechanism of protective action of CGA, myeloperoxidase (MPO), H2O2, and NF-κB levels were assessed in the colon tissue. CGA administered i.c. at the dose of 20 mg/kg (two times daily) protected against TNBS-induced colitis more effectively than the same dose administered orally (p.o.), as evidenced by significantly lower macroscopic and ulcer scores. Furthermore, CGA (20 mg/kg, i.c.) reduced neutrophil infiltration, as demonstrated by decreased MPO activity. Moreover, CGA suppressed activation of NF-κB, as evidenced by lower levels of phospho-NF-κB/NF-κB ratio in the tissue. CGA did not affect the oxidative stress pathways. CGA exhibits anti-inflammatory properties through reduction of neutrophil infiltration and inhibition of NF-κB-dependent pathways. Our results suggest that CGA may have the potential to become a valuable supplement in the treatment of GI diseases. Topics: Administration, Topical; Animals; Anti-Inflammatory Agents; Chlorogenic Acid; Colitis; Colon; Hydrogen Peroxide; Male; Mice, Inbred BALB C; NF-kappa B; Peroxidase; Trinitrobenzenesulfonic Acid | 2015 |
An adenosine A3 receptor agonist inhibits DSS-induced colitis in mice through modulation of the NF-κB signaling pathway.
The role of the adenosine A3 receptor (A3AR) in experimental colitis is controversial. The A3AR agonist N(6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA) has been shown to have a clinical benefit, although studies in A3AR-deficient mice suggest a pro-inflammatory role. However, there are no studies on the effect of 2-Cl-IB-MECA and the molecular mechanism of action of A3AR in murine colitis models in vivo. Is it the same as that observed in vitro? The interaction between 2-CL-IB-MECA and A3AR in a murine colitis model and the signaling pathways associated with this interaction remain unclear. Here we demonstrate a role for the NF-κB signaling pathway and its effect on modifying the activity of proinflammatory factors in A3AR-mediated biological processes. Our results demonstrated that A3AR activation possessed marked effects on experimental colitis through the NF-κB signaling pathway. Topics: Adenosine; Adenosine A3 Receptor Agonists; Animals; Colitis; Cytokines; Disease Models, Animal; Gene Expression; Inflammation Mediators; Intestinal Mucosa; Mice; NF-kappa B; Peroxidase; Receptor, Adenosine A3; Signal Transduction | 2015 |
Alterations of testosterone metabolism in microsomes from rats with experimental colitis induced by dextran sulfate sodium.
Down-regulation of some hepatic cytochrome P450s (CYP450s) was observed in patients and animals with ulcerative colitis (UC). This study examined changes of CYP450s activities in microsomes of liver (RLMs), intestine (RIMs) and kidney (RRMs) from rats with experimental acute colitis induced by 5% dextran sulfate sodium (DSS) for 7days and those receiving DSS treatment followed by 7-d cessation through measuring 6α-(CYP1A1), 7α-(CYP2A1), 16α-(CYP2C11) and 2β-/6β-(CYP3A2) hydroxytestosterone (OHT) formed from testosterone. Both pro-(IL-1β, IL-6, TNF-α) and anti-(IL-4, IL-10) inflammatory cytokines were elevated in acute colitis, while the production of the former was enhanced and that of the latter declined by DSS withdrawal. In RLMs, the CYP2A1 activity was significantly increased at DSS stimulation and partially returned to normal level when DSS treatment was terminated. Activity of other CYP450s were decreased by acute colitis and remained after DSS withdrawal. In RRMs, formations of 6α-, 16α- and 2β-OHT significantly declined in acute colitis and DSS termination further potentiated the down-regulation, while 7α-OHT formation was suppressed at DSS stimulation and remained after DSS withdrawal. The formation of 6β-OHT only showed significant decrease after DSS withdrawal. Two metabolites (6α- and 6β-OHT) formed in RIMs and 6β-OHT formation was significantly decreased by DSS stimulation and continued after DSS treatment halted. These findings indicate that the alterations of CYP450s activities vary with organ, CYP isoforms and colitis status, which arouse cautions on efficacy and toxicity of drug therapy during disease progression. Topics: Animals; Aryl Hydrocarbon Hydroxylases; Colitis; Colitis, Ulcerative; Cytochrome P-450 CYP1A1; Cytochrome P-450 CYP3A; Cytochrome P450 Family 2; Cytokines; Disease Models, Animal; Intestinal Mucosa; Intestines; Kidney; Male; Microsomes; Microsomes, Liver; Peroxidase; Rats, Sprague-Dawley; Steroid 16-alpha-Hydroxylase; Steroid Hydroxylases; Testosterone | 2015 |
Involvement of stimulation of α7 nicotinic acetylcholine receptors in the suppressive effect of tropisetron on dextran sulfate sodium-induced colitis in mice.
Ulcerative colitis (UC) involves chronic inflammation of the large intestine. Several agents are used to treat UC, but adverse side effects are remaining problems. We examined the effect of tropisetron as a new type of drug for UC using a dextran sulfate sodium (DSS)-induced model of colitis in mice. We developed a DSS-induced model of colitis and calculated the Disease Activity Index and colon length. We measured myeloperoxidase activity and determined the protein level and mRNA level of cytokines in the colon. DSS-induced colitis was ameliorated by administration of tropisetron and PNU282987. Pre-administration of methyllycaconitine diminished the suppressive effect of tropisetron upon DSS-induced colitis. These findings suggested that α7 nicotinic acetylcholine receptors (α7 nAChRs) were related to the suppressive effect of tropisetron on DSS-induced colitis. Additionally, stimulation of α7 nAChRs decreased the colon level of interleukin-6 and interferon-γ upon DSS administration. Furthermore, stimulation of α7 nAChRs decreased macrophage infiltration, with expression of α7 nAChR increased by DSS administration. These results suggest that the underlying mechanism of this suppressive effect on DSS-induced colitis is via stimulation of α7 nAChRs and involves suppression of expression of pro-inflammatory cytokines. Tropisetron could be a new type of therapeutic agent for UC. Topics: Aconitine; alpha7 Nicotinic Acetylcholine Receptor; Animals; Colitis; Colitis, Ulcerative; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Indoles; Inflammation Mediators; Male; Mice, Inbred ICR; Peroxidase; Tropisetron | 2015 |
Crotoxin from Crotalus durissus terrificus is able to down-modulate the acute intestinal inflammation in mice.
Inflammatory bowel diseases (IBD) is the result of dysregulation of mucosal innate and adaptive immune responses. Factors such as genetic, microbial and environmental are involved in the development of these disorders. Accordingly, animal models that mimic human diseases are tools for the understanding the immunological processes of the IBD as well as to evaluate new therapeutic strategies. Crotoxin (CTX) is the main component of Crotalus durissus terrificus snake venom and has an immunomodulatory effect. Thus, we aimed to evaluate the modulatory effect of CTX in a murine model of colitis induced by 2,4,6- trinitrobenzene sulfonic acid (TNBS). The CTX was administered intraperitoneally 18 hours after the TNBS intrarectal instillation in BALB/c mice. The CTX administration resulted in decreased weight loss, disease activity index (DAI), macroscopic tissue damage, histopathological score and myeloperoxidase (MPO) activity analyzed after 4 days of acute TNBS colitis. Furthermore, the levels of TNF-α, IL-1β and IL-6 were lower in colon tissue homogenates of TNBS-mice that received the CTX when compared with untreated TNBS mice. The analysis of distinct cell populations obtained from the intestinal lamina propria showed that CTX reduced the number of group 3 innate lymphoid cells (ILC3) and Th17 population; CTX decreased IL-17 secretion but did not alter the frequency of CD4+Tbet+ T cells induced by TNBS instillation in mice. In contrast, increased CD4+FoxP3+ cell population as well as secretion of TGF-β, prostaglandin E2 (PGE2) and lipoxin A4 (LXA4) was observed in TNBS-colitis mice treated with CTX compared with untreated TNBS-colitis mice. In conclusion, the CTX is able to modulate the intestinal acute inflammatory response induced by TNBS, resulting in the improvement of clinical status of the mice. This effect of CTX is complex and involves the suppression of the pro-inflammatory environment elicited by intrarectal instillation of TNBS due to the induction of a local anti-inflammatory profile in mice. Topics: Animals; Colitis; Crotalus; Crotoxin; Forkhead Transcription Factors; Inflammation Mediators; Interleukin-17; Male; Mice; Mice, Inbred BALB C; Peroxidase; Th17 Cells; Trinitrobenzenesulfonic Acid | 2015 |
Umbilical cord mesenchymal stem cells modulate dextran sulfate sodium induced acute colitis in immunodeficient mice.
Inflammatory bowel diseases (IBD) are complex multi-factorial diseases with increasing incidence worldwide but their treatment is far from satisfactory. Unconventional strategies have consequently been investigated, proposing the use of cells as an effective alternative approach to IBD. In the present study we examined the protective potential of exogenously administered human umbilical cord derived mesenchymal stem cells (UCMSCs) against Dextran Sulfate Sodium (DSS) induced acute colitis in immunodeficient NOD.CB17-Prkdc (scid)/J mice with particular attention to endoplasmic reticulum (ER) stress.. UCMSCs were injected in NOD.CB17-Prkdc (scid)/J via the tail vein at day 1 and 4 after DSS administration. To verify attenuation of DSS induced damage by UCMSCs, Disease Activity Index (DAI) and body weight changes was monitored daily. Moreover, colon length, histological changes, myeloperoxidase and catalase activities, metalloproteinase (MMP) 2 and 9 expression and endoplasmic reticulum (ER) stress related proteins were evaluated on day 7.. UCMSCs administration to immunodeficient NOD.CB17-Prkdc (scid)/J mice after DSS damage significantly reduced DAI (1.45 ± 0.16 vs 2.08 ± 0.18, p < 0.05), attenuating the presence of bloody stools, weight loss, colon shortening (8.95 ± 0.33 cm vs 6.8 ± 0.20 cm, p < 0.01) and histological score (1.97 ± 0.13 vs 3.27 ± 0.13, p < 0.001). Decrease in neutrophil infiltration was evident from lower MPO levels (78.2 ± 9.7 vs 168.9 ± 18.2 U/g, p < 0.01). DSS treatment enhanced MMP2 and MMP9 activities (>3-fold), which were significantly reduced in mice receiving UCMSCs. Moreover, positive modulation in ER stress related proteins was observed after UCMSCs administration.. Our results demonstrated that UCMSCs are able to prevent DSS-induced colitis in immunodeficient mice. Using these mice we demonstrated that our UCMSCs have a direct preventive effect other than the T-cell immunomodulatory properties which are already known. Moreover we demonstrated a key function of MMPs and ER stress in the establishment of colitis suggesting them to be potential therapeutic targets in IBD treatment. Topics: Acute Disease; Animals; Body Weight; Catalase; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Humans; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Inbred NOD; Peroxidase; Severity of Illness Index; Transplantation, Heterologous; Umbilical Cord | 2015 |
1,25-dihydroxyvitamin D3 regulates the development of chronic colitis by modulating both T helper (Th)1 and Th17 activation.
T helper (Th)1 and Th17 cells play a critical role in inflammatory bowel disease (IBD). 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ) has emerged as a direct regulator of immune system function. Mice were grouped as follows: Control group (received PBS, n = 10), DSS group (received 2% DSS and PBS, n = 10), and DSS+VD group (received 2% DSS and 1,25(OH)2 D3 , n = 10). The disease activity index (DAI), colon length, and damage store of the mice were observed; the spleen length, weight, spleen index, and mononuclear cells of spleen were measured; mononuclear cells from mesenteric lymph nodes (MLN) were measured, and the levels of Th 1 and Th17 cytokines in the colon mucosa and spleen were measured. Mice in the DSS group developed severe diarrhea, rectal bleeding, and marked BW loss. Histological examination revealed extensive ulceration and inflammatory cell infiltration in the colon, and the structure of the spleen was disordered, infiltrated with inflammatory cytokines in red pulp. In the DSS group, mononuclear cell numbers from MLN and spleen were increased, and enhanced proteins and mRNA levels of Th 1 and Th17 cytokines were detected. In the DSS+VD group, 1,25(OH)2 D3 ameliorated the inflammation of the colon and spleen. In addition, 1,25(OH)2 D3 down-regulated the levels of Th 1 and Th17 cytokines. 1,25(OH)2 D3 represents a novel therapeutic drug for UC, which may correlate to inhibit the activation of Th1 and Th17 cells. Topics: Animals; Calcitriol; Calcium; Chronic Disease; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Down-Regulation; Inflammation; Interferon-gamma; Interleukin-17; Interleukin-6; Intestinal Mucosa; Male; Mice; Mice, Inbred C57BL; Peroxidase; RNA, Messenger; Spleen; Th1 Cells; Th17 Cells; Tumor Necrosis Factor-alpha | 2015 |
Preventive and therapeutic effects of Lactobacillus paracasei B21060-based synbiotic treatment on gut inflammation and barrier integrity in colitic mice.
Although gut microbiota perturbation is recognized as a main contributing factor to the pathogenesis of inflammatory bowel disease, synbiotic therapies, as prevention or treatment, have remained overlooked.. To verify whether Lactobacillus paracasei B21060-based synbiotic therapy could prevent or repair colon damage in a mouse model of colitis, we performed treatments before and after colitis induction.. The experimental study lasted 19 d. Experimental colitis was induced in BALB/c mice by giving them dextran sodium sulfate (DSS, 2.5%) in drinking water (days 7-12) followed by DSS-free water (days 13-19) (DSS group). L. paracasei B21060 (2.5 × 10(7) bacteria/10 g body weight) was orally administered 7 d before DSS [synbiotic as preventive treatment (P-SYN) group] or 2 d after DSS [synbiotic as therapeutic treatment (T-SYN) group] until day 19. Another group was not treated with DSS or synbiotic and was given tap water (control group), for a total of 4 groups.. Compared with the DSS group, both synbiotic-treated groups had significantly less pronounced weight loss and colon damage. Consistently, mRNA levels of chemokine (C-C motif) ligand 5 in the colon were reduced in both P-SYN and T-SYN mice compared with the DSS group (51%, P < 0.05 and 72%, P < 0.001, respectively). In the P-SYN and T-SYN groups, neutrophil elastase transcription was also reduced (51%, P < 0.01 and 59%, P < 0.001, respectively). Accordingly, oxidative/nitrosative stress was lower in P-SYN and T-SYN mice than in the DSS group. In P-SYN and T-SYN mice, colonic gene expression of tumor necrosis factor (47%, P < 0.01 and 61%, P < 0.001, respectively) and prostaglandin-endoperoxide synthase 2 (45%, P < 0.01 and 35%, P < 0.05, respectively) was lower, whereas interleukin 10 mRNA was doubled compared with the DSS group (both P < 0.5). Remarkably, epithelial barrier integrity (zonulin and occludin) and gut protection (β-defensin and mucin expression) were completely restored in P-SYN and T-SYN mice.. Our data highlight the beneficial effects of this synbiotic formulation in acutely colitic mice, suggesting that it may have therapeutic and possibly preventive efficacy in human colitis. Topics: Animals; beta-Defensins; Colitis; Cyclooxygenase 2; Dextran Sulfate; Disease Models, Animal; Gastrointestinal Tract; Inflammation; Interleukin-10; Lactobacillus; Male; Malondialdehyde; Mice; Mice, Inbred BALB C; Mucin-1; Oxidative Stress; Peroxidase; PPAR gamma; RNA, Messenger; Synbiotics; Up-Regulation | 2015 |
Interplay between enterobactin, myeloperoxidase and lipocalin 2 regulates E. coli survival in the inflamed gut.
During an inflammatory response in the gut, some commensal bacteria such as E. coli can thrive and contribute to disease. Here we demonstrate that enterobactin (Ent), a catecholate siderophore released by E. coli, is a potent inhibitor of myeloperoxidase (MPO), a bactericidal enzyme of the host. Glycosylated Ent (salmochelin) and non-catecholate siderophores (yersiniabactin and ferrichrome) fail to inhibit MPO activity. An E. coli mutant (ΔfepA) that overproduces Ent, but not an Ent-deficient double mutant (ΔaroB/ΔfepA), inhibits MPO activity and exhibits enhanced survival in inflamed guts. This survival advantage is counter-regulated by lipocalin 2, a siderophore-binding host protein, which rescues MPO from Ent-mediated inhibition. Spectral analysis reveals that Ent interferes with compound I [oxoiron, Fe(IV)=O] and reverts the enzyme back to its native ferric [Fe(III)] state. These findings define a fundamental mechanism by which E. coli surpasses the host innate immune responses during inflammatory gut diseases and gains a distinct survival advantage. Topics: Acute-Phase Proteins; Animals; Colitis; Dextran Sulfate; Enterobactin; Escherichia coli; Female; Gene Expression Regulation; Inflammation; Lipocalin-2; Lipocalins; Mice, Inbred BALB C; Oncogene Proteins; Peroxidase; Proto-Oncogene Proteins | 2015 |
Bacteria-Derived Compatible Solutes Ectoine and 5α-Hydroxyectoine Act as Intestinal Barrier Stabilizers to Ameliorate Experimental Inflammatory Bowel Disease.
Earlier studies showed that the compatible solute ectoine (1) given prophylactically before induction of colitis by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats prevented histological changes induced in the colon and the associated rise in inflammatory mediators. This study was therefore conducted to investigate whether ectoine (1) and its 5α-hydroxy derivative (2) would also be effective in treating an already established condition. Two days after inducing colitis in rats by instilling TNBS/alcohol in the colon, animals were treated orally once daily for 1 week with either 1 or 2 (50, 100, 300 mg/kg). Twenty-four hours after the last drug administration rats were sacrificed. Ulcerative lesions and colon mass indices were reduced by 1 and 2 in a bell-shaped manner. Best results were obtained with 100 mg/kg ectoine (1) and 50 mg/kg 5α-hydroxyectoine (2). The solutes normalized the rise in myeloperoxidase, TNFα, and IL-1β induced by TNBS but did not affect levels of reduced glutathione or ICAM-1, while reducing the level of fecal calprotectin, an established marker for inflammatory bowel disease. The findings indicate that the naturally occurring compatible solutes ectoine (1) and 5α-hydroxyectoine (2) possess an optimum concentration that affords maximal intestinal barrier stabilization and could therefore prove useful for better management of human inflammatory bowel disease. Topics: Amino Acids, Diamino; Animals; Bacteria; Colitis; Colon; Egypt; Glutathione; Humans; Inflammatory Bowel Diseases; Intercellular Adhesion Molecule-1; Interleukin-1beta; Intestines; Male; Molecular Structure; Peroxidase; Rats; Rats, Wistar; Solutions; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2015 |
Anti-inflammatory effects of Brazilian ginseng (Pfaffia paniculata) on TNBS-induced intestinal inflammation: Experimental evidence.
Inflammatory bowel disease (IBD) is a chronic, relapsing, idiopathic inflammation of the gastrointestinal tract. Clinical studies suggest that the initiation of IBD is multifactorial, involving genetics, the immune system and environmental factors, such as diet, drugs and stress. Pfaffia paniculata is an adaptogenic medicinal plant used in Brazilian folk medicine as an "anti-stress" agent. Thus, we hypothesised that the P. paniculata enhances the response of animals subjected to colonic inflammation. Our aim was to investigate the intestinal anti-inflammatory activity of P. paniculata in rats before or after induction of intestinal inflammation using trinitrobenzenesulfonic acid (TNBS). The animals were divided into groups that received the vehicle, prednisolone or P. paniculata extract daily starting 14 days before or 7 days after TNBS induction. At the end of the procedure, the animals were killed and their colons were assessed for the macroscopic damage score (MDS), extent of the lesion (EL) and weight/length ratio, myeloperoxidase (MPO) activity and glutathione (GSH), cytokines and C-reactive protein (CRP) levels. Histological evaluation and ultrastructural analysis of the colonic samples were performed. Treatment with the 200mg/kg dose on the curative schedule was able to reduce the MDS and the EL. In addition, MPO activity was reduced, GSH levels were maintained, and the levels of pro-inflammatory cytokines and CRP were decreased. In conclusion, the protective effect of P. paniculata was related to reduced oxidative stress and CRP colonic levels, and due to immunomodulatory activity as evidenced by reduced levels of IL-1β, INF-γ, TNF-α and IL-6. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Cytokines; Glutathione; Male; Microscopy, Electron, Scanning; Panax; Peroxidase; Phytotherapy; Plant Extracts; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2015 |
Effects of arachidonic acid intake on inflammatory reactions in dextran sodium sulphate-induced colitis in rats.
The aim of this study was to investigate the effects of the administration of oral arachidonic acid (AA) in rats with or without dextran sulphate sodium (DSS)-induced inflammatory bowel disease. Male Wistar rats were administered AA at 0, 5, 35 or 240 mg/kg daily by gavage for 8 weeks. Inflammatory bowel disease was induced by replacing drinking water with 3 % DSS solution during the last 7 d of the AA dosing period. These animals passed loose stools, diarrhoea and red-stained faeces. Cyclo-oxygenase-2 concentration and myeloperoxidase activity in the colonic tissue were significantly increased in the animals given AA at 240 mg/kg compared with the animals given AA at 0 mg/kg. Thromboxane B2 concentration in the medium of cultured colonic mucosae isolated from these groups was found to be dose-dependently increased by AA, and the increase was significant at 35 and 240 mg/kg. Leukotriene B4 concentration was also significantly increased and saturated at 5 mg/kg. In addition, AA at 240 mg/kg promoted DSS-induced colonic mucosal oedema with macrophage infiltration. In contrast, administration of AA for 8 weeks, even at 240 mg/kg, showed no effects on the normal rats. These results suggest that in rats with bowel disease AA metabolism is affected by oral AA, even at 5 mg/kg per d, and that excessive AA may aggravate inflammation, whereas AA shows no effects in rats without inflammatory bowel disease. Topics: Animals; Arachidonic Acid; Colitis; Colon; Cyclooxygenase 2; Dextran Sulfate; Diet; Inflammation; Inflammatory Bowel Diseases; Intestinal Mucosa; Leukotriene B4; Macrophages; Male; Peroxidase; Rats, Wistar; Thromboxane B2 | 2015 |
Resveratrol Pretreatment Ameliorates TNBS Colitis in Rats.
Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disease in humans constituting a major health concern today whose prevalence has been increasing over the world. Production of reactive oxygen species (ROS) and disturbed capacity of antioxidant defense in IBD subjects have been reported. Antioxidants may play a significant role in IBD treatment. This study aimed at evaluating ameliorative effects of intraperitoneal resveratrol pretreatment on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. Thirty five Wistar-Albino female rats were divided equally into five groups. Inflammation was induced by the intrarectal administration of TNBS under anesthesia. Intraperitoneal administration of resveratrol (RSV) at a concentration of 10mg/kg/day for 5 days before the induction of colitis significantly reduced microscopy score and malondialdehyde (MDA) levels and increased glutathione peroxidase (GSH Px) activity compared to TNBS and vehicle groups. Also an insignificant increase in catalase (CAT) activity was observed in the RSV treated group compared to TNBS and vehicle groups. In this paper, the most recent patent on the identification and treatment of IBD was indicated. In conclusion, antioxidant RSV proved to have a beneficial effect on TNBS colitis in rats. In light of these advantageous results, the RSV can be considered as adjuvant agent in IBD treatments. Topics: Animals; Antioxidants; Colitis; Female; Inflammatory Bowel Diseases; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Resveratrol; Stilbenes; Superoxide Dismutase; Trinitrobenzenesulfonic Acid | 2015 |
Influence of myeloperoxidase on colon tumor occurrence in inflamed versus non-inflamed colons of Apc(Min/+) mice.
Control of colorectal cancer needs to be tailored to its etiology. Tumor promotion mechanisms in colitis-associated colon cancer differ somewhat from the mechanisms involved in hereditary and sporadic colorectal cancer. Unlike sporadic or inherited tumors, some experimental models show that colitis-associated colon tumors do not require cyclooxygenase (COX) expression for progression, and non-steroidal anti-inflammatory drugs (NSAIDs) which prevent sporadic or inherited colon cancer do not prevent colitis-associated colon cancer. We report that myeloperoxidase (MPO), an ancestor of the COX isoenzymes, is a determinant of colitis-associated colon tumors in Apc(Min/+) mice. During experimentally induced colitis, inhibition of MPO by resorcinol dampened colon tumor development. Conversely, in the bowels of Apc(Min/+) mice without colitis, resorcinol administration or 'knockout' of MPO gene coincided with a slight, but discernible increase in colon tumor incidence. Acrolein, a by-product of MPO catalysis, formed a covalent adduct with the phosphatase tensin homolog (PTEN) tumor suppressor and enhanced the activity of the Akt kinase proto-oncogene in vitro and in vivo. Thus, MPO may be an important determinant of diet and inflammation on colon cancer risk via its effect on endogenous exposure to oxidants and acrolein. We propose a hypothetical model to explain an apparent dichotomy between colon tumor occurrence and MPO inhibition in inflamed versus non-inflamed colons. Topics: Acrolein; Animals; Colitis; Colonic Neoplasms; Female; Gene Expression; Inflammation; Male; Mice; Mice, Transgenic; Oxidation-Reduction; Peroxidase; Proto-Oncogene Proteins c-akt; PTEN Phosphohydrolase; Resorcinols; RNA, Small Interfering; Sodium Dodecyl Sulfate | 2015 |
Dietary cocoa inhibits colitis associated cancer: a crucial involvement of the IL-6/STAT3 pathway.
Patients with inflammatory bowel disease (IBD) are at increased risk for developing ulcerative colitis-associated colorectal cancer (CRC). The interleukin-6 (IL-6)/signal transducer and activator of transcription (STAT)-3 signaling regulates survival and proliferation of intestinal epithelial cells and play an important role in the pathogenesis of IBD and CRC. Cocoa is enriched with polyphenols that known to possess antioxidant, anti-inflammatory and antitumor activities. Here, we explored the antitumor effects and mechanisms of cocoa diet on colitis-associated cancer (CAC) using the azoxymethane/dextran sulfate sodium model, with a particular focus on whether cocoa exerts its anticancer effect through the IL-6/STAT3 pathway. We found that cocoa significantly decreased the tumor incidence and size in CAC-induced mice. In addition to inhibiting proliferation of tumor epithelial cells, cocoa suppressed colonic IL-6 expression and subsequently activation of STAT3. Thus, our findings demonstrated that cocoa diet suppresses CAC tumorigenesis, and its antitumor effect is partly mediated by limiting IL-6/STAT3 activation. In addition, cocoa induces apoptosis by increased the expressions of Bax and caspase 3 and decreased Bcl-xl. Thus, we conclude that cocoa may be a potential agent in the prevention and treatment of CAC. Topics: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Antioxidants; Apoptosis; Azoxymethane; bcl-2-Associated X Protein; bcl-X Protein; Cacao; Caspase 3; Colitis; Colorectal Neoplasms; Dextran Sulfate; Diet; Epithelial Cells; Female; Gene Expression Regulation; Inflammatory Bowel Diseases; Interleukin-6; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Microscopy, Confocal; Neoplasms; Peroxidase; Polyphenols; Signal Transduction; STAT3 Transcription Factor | 2015 |
Brugia malayi cystatin therapeutically ameliorates dextran sulfate sodium-induced colitis in mice.
Helminth immunomodulation in the host has been shown to have therapeutic implications in inflammatory bowel diseases. In this study we aimed to evaluate the therapeutic effect of Brugia malayi recombinant cystatin (rBmCys) in a dose-dependent manner on dextran sulfate sodium (DSS)-induced colitis in mice.. The anti-inflammatory activity of rBmCys on mice peritoneal exudate cells was initially analyzed in vitro. BALB/c mice were fed with 5% DSS for 7 days to induce colitis. The colitis mice were treated intraperitoneally with rBmCys (10, 25 or 50 µg for the three different groups of mice) on days 1, 3 and 5 of the DSS administration. Disease severity was assessed by the disease activity index (DAI) and macroscopic and histopathological scores of colon and myeloperoxidase activity in colonic mucosa. Cytokine profiles were measured in sera and cultured splenocytes of treated mice followed by stimulation with rBmCys.. rBmCys showed anti-inflammatory activity in vitro. Treatment of DSS-induced colitis with rBmCys in mice ameliorated the overall disease severity as reflected by a significant reduction in weight loss, the DAI, mucosal edema, colon damage and myeloperoxidase activity of the colonic mucosa. While the mRNA expressions of IFN-γ, TNF-α, interleukin (IL)-5, IL-6 and IL-17 were downregulated, IL-10 expression was upregulated in the splenocytes of colitis mice treated with rBmCys. The amelioration of DSS-induced colitis occurred in a dose-dependent manner.. The results of this study indicate an anti-inflammatory potential of rBmCys and provide evidence for using this protein as a promising therapeutic agent in ulcerative colitis. Topics: Animals; Anti-Inflammatory Agents; Brugia malayi; Colitis; Colon; Cystatins; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Helminth Proteins; Interferon-gamma; Interleukin-10; Interleukin-17; Interleukin-5; Interleukin-6; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Peroxidase; RNA, Messenger; Tumor Necrosis Factor-alpha; Weight Loss | 2015 |
Dendritic cell immunoreceptor 1 alters neutrophil responses in the development of experimental colitis.
Ulcerative colitis, an inflammatory bowel disease, is associated with the massive infiltration of neutrophils. Although the initial infiltration of neutrophils is beneficial for killing bacteria, it is presumed that persistent infiltration causes tissue damage by releasing antibacterial products as well as inflammatory cytokines. A murine C-type lectin receptor, dendritic cell immunoreceptor 1 (Dcir1), is expressed on CD11b(+) myeloid cells, such as macrophages, dendritic cells and neutrophils. It was reported that Dcir1 is required to maintain homeostasis of the immune system to prevent autoimmunity, but it is also involved in the development of infectious disease resulting in the enhanced severity of cerebral malaria. However, the role of Dcir1 in intestinal immune responses during colitis remains unclear. In this study, we investigated the role of Dcir1 in intestinal inflammation using an experimental colitis model induced with dextran sodium sulfate (DSS).. In contrast to wild type (WT) mice, Dcir1 (-/-) mice exhibited mild body weight loss during the course of DSS colitis accompanied by reduced colonic inflammation. Dcir1 deficiency caused a reduced accumulation of neutrophils in the inflamed colon on day 5 of DSS colitis compared with WT mice. Consistently, the production of a neutrophil-attracting chemokine, MIP-2, was also decreased in the Dcir1 (-/-) colon compared with the WT colon on day 5. There were fewer myeloperoxidase-positive neutrophils in the inflamed colon of Dcir1 (-/-) mice than in that of WT mice. Moreover, bone marrow neutrophils from Dcir1 (-/-) mice produced less reactive oxygen species (ROS) by lipopolysaccharide stimulation than those from WT mice. This suggests that Dcir1 deficiency decreases the accumulation of tissue destructive neutrophils during DSS colitis.. Dcir1 enhances the pathogenesis of DSS colitis by altering neutrophil recruitment and their functions. Topics: Animals; Chemokine CXCL2; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Lectins, C-Type; Leukocyte Count; Lipopolysaccharides; Mice; Mice, Knockout; Neutrophil Infiltration; Neutrophils; Peroxidase; Reactive Oxygen Species; Respiratory Burst | 2015 |
Oleanolic acid ameliorates dextran sodium sulfate-induced colitis in mice by restoring the balance of Th17/Treg cells and inhibiting NF-κB signaling pathway.
In a preliminary experiment, it was found that oleanolic acid (OA), which is widely distributed in food and medicinal plants, inhibited interleukin (IL)-6/tumor growth factor beta-induced differentiation of splenic T cells into Th17 cells. Moreover, OA induced the differentiation of splenic T cells into Treg cells. Therefore, we examined the anti-inflammatory effect of OA in mice with dextran sodium sulfate (DSS)-induced colitis. Oral administration of OA significantly inhibited DSS-induced colon shortening, macroscopic score, and myeloperoxidase activity. Treatment with OA inhibited DSS-induced differentiation to Th17 cells and downregulated the expression of RORγt and IL-17 in the lamina propria of colon and Treg cell differentiation and Foxp3 and IL-10 expression were increased. OA treatment increased the DSS-suppressed expression of tight junction proteins such as ZO-1, occludin, and claudin-1 in the colon. Moreover, OA treatment inhibited DSS-induced expression of tumor necrosis factor-α, interleukin (IL)-1β, and IL-17, the activation of NF-κB and mitogen-activated protein kinases, and increased IL-10 expression. OA also inhibited the activation of NF-κB and expression of proinflammatory cytokines in LPS-stimulated peritoneal macrophages. These findings suggest that OA may ameliorate inflammatory diseases such as colitis by inhibiting Th17 cell differentiation and increasing Treg cell differentiation. Topics: Animals; Caco-2 Cells; Colitis; Colon; Dextran Sulfate; Humans; Interleukin-17; Macrophages, Peritoneal; Male; Mice; Mice, Inbred C57BL; NF-kappa B; Nuclear Receptor Subfamily 1, Group F, Member 3; Oleanolic Acid; Peroxidase; Signal Transduction; Spleen; T-Lymphocytes, Regulatory; Th17 Cells | 2015 |
Anti-inflammatory effects of nesfatin-1 in rats with acetic acid - induced colitis and underlying mechanisms.
Mucosal balance impairment, bacterial over-proliferation, cytokines, inflammatory mediators are known as responsible for inflammatory bowel disease. Besides known anorexigenic, neuroprotective, and anti-apoptotic effects, the major effect of nesfatin-1 on colitis is unknown. Our aim was to investigate the possible anti-inflammatory effects of nesfatin-1 in acetic acid induced colitis model and potential underlying mechanisms. Male Spraque-Dawley rats were anesthetized by intraperitoneal ketamine (100 mg/kg) and chlorpromazine (0.75 mg/kg). For nesfatin-1 and antagonist applications some of the rats were intracerebroventricularly (i.c.v.) cannulated. In colitis group, intrarectally (i.r.) 4% acetic acid solution (1 ml) and 10 minutes later i.c.v. nesfatin-1 (0.05 μg/5 μl) or vehicle (5 μl) were administered. Treatments continued for 3 days. In control group, physiological saline solution was used intrarectally. To identify the underlying effective mechanism of nesfatin-1, rats were divided into 3 subgroups, 5 minutes following colitis induction; i.c.v. atosiban (oxytocin receptor antagonist), SHU9119 (melanocortin receptor antagonist) or GHSR-1a antagonist (ghrelin receptor antagonist) were administered, 5 minutes later nesfatin-1 was administered for 3 days. On the fourth day, rats were decapitated, and colon tissues were sampled. Macroscopic and microscopic damage scores of distal colon, and colonic tissue malondialdehyde, glutathione, myeloperoxidase, superoxide dismutase, catalase, luminol and lucigenin chemiluminescence measurements were analysed. The increased myeloperoxidase activity, malondialdehyde levels, luminol and lucigenin chemiluminescence measurements, macroscopic and microscopic damage scores with colitis induction (P < 0.05 - 0.001) were decreased with nesfatin-1 treatment (P < 0.05 - 0.001). Nesfatin-1 may show this effect by inhibiting neutrophil infiltration through tissues and by decreasing formation of free oxygen radicals. Atosiban and GHSR-1a administration alleviated the protective effect of nesfatin-1 from microscopic and oxidant damage parameters and lipid peroxidation (P < 0.05 - 0.001). The results of the study suggest that nesfatin-1 had a protective effect from colitis induction, and the anti-inflammatory and antioxidant effects of nesfatin-1 on colitis might occur via oxytocin and ghrelin receptors. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Calcium-Binding Proteins; Colitis; Disease Models, Animal; DNA-Binding Proteins; Glutathione; Lipid Peroxidation; Male; Malondialdehyde; Nerve Tissue Proteins; Nucleobindins; Peroxidase; Rats; Rats, Sprague-Dawley | 2015 |
CYP4F18-Deficient Neutrophils Exhibit Increased Chemotaxis to Complement Component C5a.
CYP4Fs were first identified as enzymes that catalyze hydroxylation of leukotriene B4 (LTB4). CYP4F18 has an unusual expression in neutrophils and was predicted to play a role in regulating LTB4-dependent inflammation. We compared chemotaxis of wild-type and Cyp4f18 knockout neutrophils using an in vitro assay. There was no significant difference in the chemotactic response to LTB4, but the response to complement component C5a increased 1.9-2.25-fold in knockout cells compared to wild-type (P < 0.01). This increase was still observed when neutrophils were treated with inhibitors of eicosanoid synthesis. There were no changes in expression of other CYP4 enzymes in knockout neutrophils that might compensate for loss of CYP4F18 or lead to differences in activity. A mouse model of dextran sodium sulfate colitis was used to investigate the consequences of increased C5a-dependent chemotaxis in vivo, but there was no significant difference in weight loss, disease activity, or colonic tissue myeloperoxidase between wild-type and Cyp4f18 knockout mice. This study demonstrates the limitations of inferring CYP4F function based on an ability to use LTB4 as a substrate, points to expanding roles for CYP4F enzymes in immune regulation, and underscores the in vivo challenges of CYP knockout studies. Topics: Animals; Bone Marrow Cells; Chemokine CXCL1; Chemotaxis, Leukocyte; Colitis; Complement C5a; Cytochrome P-450 Enzyme System; Cytochrome P450 Family 4; Dextran Sulfate; Female; Gene Expression Profiling; Gene Expression Regulation; Humans; Isoenzymes; Leukotriene B4; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; Peptides; Peroxidase; Primary Cell Culture; Receptors, Formyl Peptide; Weight Loss | 2015 |
Kefir treatment ameliorates dextran sulfate sodium-induced colitis in rats.
To investigate the preventive effect of kefir on colitis induced with dextran sulfate sodium (DSS) in rats.. Twenty-four male Wistar-albino rats were randomized into four groups: normal control, kefir-control, colitis, and kefir-colitis groups. Rats in the normal and kefir-control groups were administered tap water as drinking water for 14 d. Rats in the colitis and kefir-colitis groups were administered a 3% DSS solution as drinking water for 8-14 d to induce colitis. Rats in the kefir-control and kefir-colitis groups were administered 5 mL kefir once a day for 14 d while rats in the normal control and colitis group were administered an identical volume of the placebo (skim milk) using an orogastric feeding tube. Clinical colitis was evaluated with reference to the disease activity index (DAI), based on daily weight loss, stool consistency, and presence of bleeding in feces. Rats were sacrificed on the 15(th) day, blood specimens were collected, and colon tissues were rapidly removed. Levels of myeloperoxidase (MPO), tumor necrosis factor (TNF)-α, interleukin (IL)-10, malondialdehyde, and inducible nitric oxide synthase (iNOS) were measured in colon tissue.. The DAI was lower in the kefir-colitis group than in the colitis group (on the 3(rd) and 5(th) days of colitis induction; P < 0.01). The DAI was also significantly higher in the colitis group between days 2 and 6 of colitis induction when compared to the normal control and kefir-control groups. The DAI was statistically higher only on the 6(th) day in the kefir-colitis group when compared to that in the normal control groups. Increased colon weight and decreased colon length were observed in colitis-induced rats. Mean colon length in the colitis group was significantly shorter than that of the kefir-control group. Kefir treatment significantly decreased histologic colitis scores (P < 0.05). MPO activity in the colitis group was significantly higher than in the kefir-control group (P < 0.05). Kefir treatment significantly reduced the DSS colitis-induced TNF-α increase (P < 0.01). No statistically significant differences were observed among groups for IL-10 and MDA levels. Colon tissue iNOS levels in the colitis group were significantly higher than those in the control and kefir-colitis groups (P < 0.05).. Kefir reduces the clinical DAI and histologic colitis scores in a DSS-induced colitis model, possibly via reduction of MPO, TNF-α, and iNOS levels. Topics: Animals; Colitis; Colon; Cultured Milk Products; Dextran Sulfate; Disease Models, Animal; Down-Regulation; Inflammation Mediators; Interleukin-10; Male; Malondialdehyde; Nitric Oxide Synthase Type II; Peroxidase; Rats, Wistar; Time Factors; Tumor Necrosis Factor-alpha | 2015 |
The influence of pretreatment with ghrelin on the development of acetic-acid-induced colitis in rats.
Ghrelin has been primarily shown to exhibit protective and therapeutic effect in the gut. Pretreatment with ghrelin inhibits the development of acute pancreatitis and accelerates pancreatic recovery in the course of this disease. In the stomach, ghrelin reduces gastric mucosal damage induced by ethanol, stress or alendronate, as well as accelerates the healing of acetic acid-induced gastric and duodenal ulcer. The aim of present studies was to investigate the effect of pretreatment with ghrelin on the development of acetic acid-induced colitis. Studies have been performed on male Wistar rats. Animals were treated intraperitoneally with saline (control) or ghrelin (4, 8 or 16 nmol/kg/dose). Saline or ghrelin was given twice: 8 and 1 h before induction of colitis. Colitis was induced by a rectal enema with 1 ml of 4% solution of acetic acid and the severity of colitis was assessed 1 or 24 hours after induction of inflammation. Rectal administration of acetic acid induced colitis in all animals. Damage of colonic wall was seen at the macroscopic and microscopic level. This effect was accompanied by a reduction in colonic blood flow and mucosal DNA synthesis. Moreover, induction of colitis significantly increased mucosal concentration of pro-inflammatory interleukin-1β (IL-1β), activity of myeloperoxidase and concentration of malondialdehyde (MDA). Mucosal activity of superoxide dismutase (SOD) was reduced. Pretreatment with ghrelin reduced the area and grade of mucosal damage. This effect was accompanied by an improvement of blood flow, DNA synthesis and SOD activity in colonic mucosa. Moreover, ghrelin administration reduced mucosal concentration of IL-1β and MDA, as well as decreased mucosal activity of myeloperoxidase. Administration of ghrelin protects the large bowel against the development of the acetic acid-induced colitis and this effect seems to be related to the ghrelin-evoked anti-inflammatory and anti-oxidative effects. Topics: Acetic Acid; Animals; Colitis; Colon; DNA; Ghrelin; Interleukin-1beta; Intestinal Mucosa; Male; Malondialdehyde; Peroxidase; Protective Agents; Rats, Wistar; Regional Blood Flow; Superoxide Dismutase | 2015 |
Antioxidant and intestinal anti-inflammatory effects of plant-derived coumarin derivatives.
Coumarins, also known as benzopyrones, are plant-derived products with several pharmacological properties, including antioxidant and anti-inflammatory activities. Based on the wide distribution of coumarin derivatives in plant-based foods and beverages in the human diet, our objective was to evaluate both the antioxidant and intestinal anti-inflammatory activities of six coumarin derivatives of plant origin (scopoletin, scoparone, fraxetin, 4-methyl-umbeliferone, esculin and daphnetin) to verify if potential intestinal anti-inflammatory activity was related to antioxidant properties.. Intestinal inflammation was induced by intracolonic instillation of TNBS in rats. The animals were treated with coumarins by oral route. The animals were killed 48 h after colitis induction. The colonic segments were obtained after laparotomy and macroscopic and biochemical parameters (determination of glutathione level and myeloperoxidase and alkaline phosphatase activities) were evaluated. The antioxidant properties of these coumarins were examined by lipid peroxidation and DPPH assays.. Treatment with esculin, scoparone and daphnetin produced the best protective effects. All coumarin derivatives showed antioxidant activity in the DPPH assay, while daphnetin and fraxetin also showed antioxidant activity by inhibiting lipid peroxidation. Coumarins, except 4-methyl-umbeliferone, also showed antioxidant activity through the counteraction of glutathione levels or through the inhibition of myeloperoxidase activity.. The intestinal anti-inflammatory activity of coumarin derivatives were related to their antioxidant properties, suggesting that consumption of coumarins and/or foods rich in coumarin derivatives, particularly daphnetin, esculin and scoparone, could prevent intestinal inflammatory disease. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Antioxidants; Biphenyl Compounds; Colitis; Colon; Coumarins; Esculin; Glutathione; Inflammation; Inflammatory Bowel Diseases; Lipid Peroxidation; Male; Oxidative Stress; Peroxidase; Phytotherapy; Picrates; Plant Extracts; Rats; Rats, Wistar; Umbelliferones | 2014 |
Prophylactic systemic P2X7 receptor blockade prevents experimental colitis.
The P2X7 receptor (P2X7-R) is a non-selective adenosine triphosphate-gated cation channel present in epithelial and immune cells, and involved in inflammatory response. Extracellular nucleotides released in conditions of cell stress or inflammation may function as a danger signal alerting the immune system from inflammation. We investigated the therapeutic action of P2X7-R blockade in a model of inflammatory bowel disease.. Rats with trinitrobenzene sulfonic (TNBS) acid-induced colitis were treated with the P2X7-R antagonists A740003 or brilliant blue G (BBG) through intra-peritoneal (IP) or intra-colonic (IC) injection prior to colitis induction. Clinical and endoscopic follow-up, histological scores, myeloperoxidase activity, densities of collagen fibers and goblet cells were evaluated. P2X7-R expression, NF-kappa B and Erk activities, and densities of T-cells and macrophages were analyzed by immunoperoxidase. The inflammatory response was determined by measuring inflammatory cytokines in cultures of colon explants, by enzyme-linked immunosorbent assay. Colonic apoptosis was determined by the TUNEL assay.. IP-BBG significantly attenuated the severity of colitis, myeloperoxidase activity, collagen deposition, densities of lamina propria T-cells and macrophages, while maintaining goblet cell densities. IP-BBG inhibited the increase in P2X7-R expression in parallel with apoptotic rates. TNF-α and interleukin-1β stabilized in low levels, while TGF-β and interleukin-10 did not change following IP-BBG-therapy. Colonic NF-kappa-B and Erk activation were significantly lower in IP-BBG-treated animals. Prophylactic IP-A740003 also protected rats against the development of TNBS-colitis.. Prophylactic systemic P2X7-R blockade is effective in the prevention of experimental colitis, probably due to a systemic anti-inflammatory action, interfering with a stress-inflammation amplification loop mediated by P2X7-R. Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Colitis; Collagen; Colon; Extracellular Signal-Regulated MAP Kinases; Gene Expression; Goblet Cells; Injections, Intraperitoneal; Macrophages; Male; NF-kappa B; Peroxidase; Purinergic P2X Receptor Antagonists; Rats; Rats, Wistar; Receptors, Purinergic P2X7; Rosaniline Dyes; T-Lymphocytes; Trinitrobenzenesulfonic Acid | 2014 |
Paeoniflorin abrogates DSS-induced colitis via a TLR4-dependent pathway.
Paeonia lactiflora Pall is one of the most well-known herbs in China, Korea, and Japan for more than 1,200 years. Paeoniflorin, the major bioactive component of peony root, has recently been reported to have anticolitic activity. However, the underlying molecular mechanism is unclear. The present study was to explore the possible mechanism of paeoniflorin in attenuating dextran sulfate sodium (DSS)-induced colitis. Pre- and coadministration of paeoniflorin significantly reduced the severity of colitis and resulted in downregulation of several inflammatory parameters in the colon, including the activity of myeloperoxidase (MPO), the levels of TNF-α and IL-6, and the mRNA expression of proinflammatory mediators (MCP-1, Cox2, IFN-γ, TNF-α, IL-6, and IL-17). The decline in the activation of NF-κB p65, ERK, JNK, and p38 MAPK correlated with a decrease in mucosal Toll-like receptor 4 (TLR4) but not TLR2 or TLR5 expression. In accordance with the in vivo results, paeoniflorin downregulated TLR4 expression, blocked nuclear translocation of NF-κB p65, and reduced the production of IL-6 in LPS-stimulated mouse macrophage RAW264.7 cells. Transient transfection assay performed in LPS-stimulated human colon cancer HT-29 cells indicated that paeoniflorin inhibits NF-κB transcriptional activity in a dose-dependent manner. TLR4 knockdown and overexpression experiments demonstrated a requirement for TLR4 in paeoniflorin-mediated downregulation of inflammatory cytokines. Thus, for the first time, the present study indicates that paeoniflorin abrogates DSS-induced colitis via decreasing the expression of TLR4 and suppressing the activation of NF-κB and MAPK pathways. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzoates; Biological Availability; Bridged-Ring Compounds; Colitis; Dextran Sulfate; Drugs, Chinese Herbal; Gene Expression Profiling; Glucosides; HT29 Cells; Humans; Inflammation; Interleukin-6; MAP Kinase Signaling System; Mice; Mitogen-Activated Protein Kinases; Models, Animal; Monoterpenes; NF-kappa B; Paeonia; Peroxidase; Protein Biosynthesis; Toll-Like Receptor 4; Transcriptional Activation; Tumor Necrosis Factor-alpha | 2014 |
Effect of salicin on gut inflammation and on selected groups of gut microbiota in dextran sodium sulfate induced mouse model of colitis.
This study was undertaken to evaluate the anti-inflammatory effect of the pure compound salicin on dextran sulfate sodium (DSS)-induced colitis in a mouse model and to quantify the major gut bacteria during the treatment.. Experimental colitis was induced in Swiss albino mice by dissolving 2 % DSS in their drinking water for 7 days. Five mice were used in each group.. Salicin (100 and 200 mg per body weight) was administered daily through oral gavage for 7 days.. Disease activity index (DAI), colon length, myeloperoxidase (MPO) assay, pro-inflammatory cytokine expression, histological changes and absolute number of gut microbiota were measured after treatment. Student's t test was applied for statistical analysis.. Salicin significantly attenuated DSS-induced DAI scores, shortening of colon length and tissue MPO activity. Salicin administration also effectively and dose-dependently prevented pro-inflammatory cytokine expression in DSS-induced colitis mice. Histological examination indicated that salicin suppressed edema, mucosal damage and the loss of crypts induced by DSS. Oral administration of salicin in DSS-treated mice prevented loss of gut microbiota during the short period of treatment.. Salicin has an anti-inflammatory effect, and it may have therapeutic value in ameliorating inflammation during colitis. Topics: Animals; Anti-Inflammatory Agents; Bacteria; Bacterial Load; Benzyl Alcohols; Colitis; Colon; Cytokines; Dextran Sulfate; Feces; Glucosides; Intestines; Male; Mice; Microbiota; Peroxidase; RNA, Bacterial; RNA, Messenger; RNA, Ribosomal, 16S | 2014 |
Protective effect of marine mangrove Rhizophora apiculata on acetic acid induced experimental colitis by regulating anti-oxidant enzymes, inflammatory mediators and nuclear factor-kappa B subunits.
Ulcerative colitis is a disease that causes inflammation and ulcer in the lining of the large intestine. In this study we investigate the effect of Rhizophora apiculata (R. apiculata) on acetic acid induced colitis in mouse model. Experimental animals were randomized into four groups: normal untreated, colitis control, R. apiculata treated group and sulfasalazine treated group. R. apiculata significantly (p<0.01) decreased macroscopic score and wet weight of damaged colon compared to colitis control. This effect was confirmed biochemically by significant (p<0.01) reduction of colitis associated increase in myeloperoxidase activity. R. apiculata significantly (p<0.05) increased anti-oxidant enzymes such as superoxide dismutase (SOD) and glutathione (GSH) levels compared to colitis control. R. apiculata significantly (p<0.01) reduced lipid peroxides (LPO), nitric oxide (NO) and inflammatory mediators such as myeloperoxidase (MPO), lactate dehydrogenase (LDH), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and tumor necrosis factor-α (TNF-α) expressions compared to colitis control. R. apiculata treatment significantly (p<0.01) inhibits the translocation of NF-kB p65 and p50 subunits. Taken together these findings suggest that R. apiculata prevents acetic acid induced colitis in experimental mouse model and may serve as an excellent anti-oxidant and anti-inflammatory agent that could potentially be useful as a (natural) therapy for inflammatory bowel disease (IBD). Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Cells, Cultured; Colitis; Colon; Cytokines; Humans; Inflammation Mediators; Inflammatory Bowel Diseases; Male; Mice; Mice, Inbred BALB C; Models, Animal; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Plant Extracts; Rhizophoraceae; Superoxide Dismutase | 2014 |
Role of the A(2B) receptor-adenosine deaminase complex in colonic dysmotility associated with bowel inflammation in rats.
Adenosine A(2B) receptors regulate several physiological enteric functions. However, their role in the pathophysiology of intestinal dysmotility associated with inflammation has not been elucidated. Hence, we investigated the expression of A2B receptors in rat colon and their role in the control of cholinergic motility in the presence of bowel inflammation.. Colitis was induced by 2,4-dinitrobenzenesulfonic acid (DNBS). Colonic A(2B) receptor expression and localization were examined by RT-PCR and immunofluorescence. The interaction between A(2B) receptors and adenosine deaminase was assayed by immunoprecipitation. The role of A(2B) receptors in the control of colonic motility was examined in functional experiments on longitudinal muscle preparations (LMPs).. A(2B) receptor mRNA was present in colon from both normal and DNBS-treated rats but levels were increased in the latter. A(2B) receptors were predominantly located in the neuromuscular layer, but, in the presence of colitis, were increased mainly in longitudinal muscle. Functionally, the A(2B) receptor antagonist MRS 1754 enhanced both electrically-evoked and carbachol-induced cholinergic contractions in normal LMPs, but was less effective in inflamed tissues. The A(2B) receptor agonist NECA decreased colonic cholinergic motility, with increased efficacy in inflamed LMP. Immunoprecipitation and functional tests revealed a link between A(2B) receptors and adenosine deaminase, which colocalize in the neuromuscular compartment.. Under normal conditions, endogenous adenosine modulates colonic motility via A2B receptors located in the neuromuscular compartment. In the presence of colitis, this inhibitory control is impaired due to a link between A2B receptors and adenosine deaminase, which catabolizes adenosine, thus preventing A(2B) receptor activation. Topics: Adenine; Adenosine Deaminase; Adenosine Deaminase Inhibitors; Animals; Benzenesulfonates; Colitis; Colon; Gastrointestinal Motility; In Vitro Techniques; Male; Muscle Contraction; Muscle, Smooth; Peroxidase; Rats; Rats, Sprague-Dawley; Receptor, Adenosine A2B; Tumor Necrosis Factor-alpha | 2014 |
Estrogen alleviates acetic acid-induced gastric or colonic damage via both ERα- and ERβ-mediated and direct antioxidant mechanisms in rats.
In order to demonstrate the possible protective effects of estrogen receptor (ER)-α and ERβ receptor subtypes in the pathogenesis of colonic and gastric oxidant damage, experimental ulcer and colitis were induced by acetic acid, and the animals were randomly divided as colitis, ulcer, and their corresponding non-ulcer and non-colitis control groups. Each group of rats was treated intramuscularly with the vehicle, selective ERα agonist propylpyrazole-triol (1 mg/kg), ERβ agonist diarylpropionitrile (1 mg/kg), non-selective ER agonist 17β estradiol (E2; 1 mg/kg), or E2 plus non-selective ER antagonist ICI-182780 (1 mg/kg). The results revealed that induction of ulcer or colitis resulted in systemic inflammation as assessed by increased levels of plasma TNF-α and IL-6 levels. In both tissues, the presence of oxidant damage was verified by histological analysis and elevated myleoperoxidase activity. In the colitis and ulcer groups, both ER agonists and the non-selective E2 reversed the oxidative damage in a similar manner. These findings indicate that estrogen acts via both ERα- and ERβ-mediated and direct antioxidant mechanisms, where both ER subtypes play equal and efficient roles in the anti-inflammatory action of estrogen, in limiting the migration of neutrophils to the inflamed tissue, reducing the release and activation of cytokines and thereby alleviating tissue damage. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Cell Movement; Colitis; Cytokines; Estradiol; Estrogen Receptor Antagonists; Estrogens; Fulvestrant; Interleukin-6; Male; Neutrophils; Nitriles; Oxidative Stress; Peroxidase; Phenols; Propionates; Pyrazoles; Random Allocation; Rats; Rats, Wistar; Receptors, Estrogen; Stomach Ulcer; Tumor Necrosis Factor-alpha | 2014 |
The commensal bacterium Faecalibacterium prausnitzii is protective in DNBS-induced chronic moderate and severe colitis models.
The abundance of Faecalibacterium prausnitzii, an abundant and representative bacterium of Firmicutes phylum, has consistently been observed to be lower in patients with Crohn's disease than in healthy individuals. We have shown that both F. prausnitzii and its culture supernatant (SN) have anti-inflammatory and protective effects in a TNBS-induced acute colitis mouse model. Here, we tested the effects of both F. prausnitzii and its SN in moderate and severe DNBS-induced chronic colitis mouse models.. Colitis was induced by intrarectal administration of DNBS. After either 4 or 10 days of recovery (severe and moderate protocols, respectively), groups of mice were intragastrically administered either with F. prausnitzii A2-165 or with its culture SN for 7 or 10 days. Three days before being sacrificed, colitis was reactivated by administration of a lower dose of DNBS. The severity of colitis at the time of being sacrificed was assessed by weight loss and macroscopic and microscopic scores. Myeloperoxidase (MPO) activity, cytokine levels, lymphocyte populations, and changes in microbiota were studied.. Intragastric administration of either F. prausnitzii or its SN led to a significant decrease in colitis severity in both severe and moderate chronic colitis models. The lower severity of colitis was associated with down-regulation of MPO, pro-inflammatory cytokines, and T-cell levels.. We show, for the first time, protective effects of both F. prausnitzii and its SN during both the period of recovery from chronic colitis and colitis reactivation. These results provide further evidence that F. prausnitzii is an anti-inflammatory bacterium with therapeutic potential for patients with inflammatory bowel disease. Topics: Animals; Chronic Disease; Colitis; Dinitrofluorobenzene; Disease Models, Animal; Lactococcus lactis; Male; Mice; Mice, Inbred C57BL; Peroxidase; Probiotics; Prognosis; Ruminococcus | 2014 |
Anti-inflammatory effects of mannanase-hydrolyzed copra meal in a porcine model of colitis.
We evaluated the anti-inflammatory activity of mannanase-hydrolyzed copra meal (MNB), including β-1,4-mannobiose (67.8%), in a dextran sodium sulfate (DSS)-induced porcine model of intestinal inflammation. In the DSS-positive control (POS) and MNB treatment (MCM) groups, DSS was first administered to piglets via intragastric catheter for 5 days, followed by 5 days administration of saline or MCM. A negative control group (NEG) received a saline alternative to DSS and MNB. Inflammation was assessed by clinical signs, morphological and histological measurements, gut permeability and neutrophil infiltration. Local production of TNF-α and IL-6 were analyzed by ELISA, colonic and ileal inflammatory gene expressions were assessed by real time RT-PCR, and CD4+CD25+ cell populations were analyzed by flow cytometry. Crypt elongation and muscle thickness, D-mannitol gut permeation, colonic expression of the inflammatory mediators TNF-α and IL-6 and myeloperoxidase activity were significantly lower in the MCM group than in that of POS group. The mRNA levels of ileal IL-1β, IL-6, IL-17 and TNF-α were significantly lower following MCM treatment than with POS treatment.MNB exerts anti-inflammatory activity in vivo, suggesting that MNB is a novel therapeutic that may provide relief to human and animals suffering from intestinal inflammation. Topics: Animal Feed; Animals; Anti-Inflammatory Agents; Cocos; Colitis; Dextran Sulfate; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Hydrolysis; Interleukin-6; Mannosidases; Peroxidase; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; Swine; Tumor Necrosis Factor-alpha | 2014 |
Anti-inflammatory effects of carbon monoxide-releasing molecule on trinitrobenzene sulfonic acid-induced colitis in mice.
Recent findings indicate that carbon monoxide (CO) in non-toxic doses exerts a beneficial anti-inflammatory action in various experimental models. However, the precise anti-inflammatory mechanism of CO in the intestine remains unclear. Here, we assessed the effects of a novel water-soluble CO-releasing molecule, CORM-3, on trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice.. To induce colitis, C57BL/6 male mice received an enema of TNBS. CORM-3 or its inactive compound, iCORM-3, were administered intraperitoneally, once immediately before, and twice daily after receiving an enema of TNBS. Three days after TNBS administration, the distal colon was removed, assessed for colonic damage and histological scores, polymorphonuclear leukocyte recruitment (tissue-associated myeloperoxidase, MPO activity), and TNF-α, IFN-γ and IL-17A expression (mRNA and protein levels in the colon mucosa). CD4(+) T cells isolated from murine spleens were stimulated with anti-CD3/CD28, in the presence or absence of CORM-3/iCORM-3. The cell supernatants were assessed for TNF-α and IFN-γ expression, 24 h following stimulation.. Colonic damage and histological scores were significantly increased in TNBS-induced mice compared to sham-operated mice. Tissue-associated MPO activity and expression of TNF-α, IFN-γ, and IL-17A in the colonic mucosa were higher in TNBS-induced colitis mice. The above changes were attenuated in CORM-3-treated mice. Further, CORM-3 was effective in reducing TNF-α and IFN-γ production in anti-CD3/CD28-stimulated CD4(+) T cells.. These findings indicate that CO released from CORM-3 ameliorates inflammatory responses in the colon of TNBS-challenged mice at least in part through a mechanism that involves the suppression of inflammatory cell recruitment/activation. Topics: Animals; Antimetabolites; Carbon Monoxide; Colitis; Colon; Cytokines; Gene Expression Regulation; Male; Mice; Organometallic Compounds; Peroxidase; Spleen; Trinitrobenzenesulfonic Acid | 2014 |
Role of neurokinin 1 receptors in dextran sulfate-induced colitis: studies with gene-deleted mice and the selective receptor antagonist netupitant.
The function of the neurokinin 1 (NK1) receptor was investigated in the DSS-induced mouse colitis model using NK1 receptor-deficient mice and the selective antagonist netupitant.. Colitis was induced by oral administration of 20 mg/ml DSS solution for 7 days in C57BL/6 and Tacr1 KO animals (n = 5-7).. During the induction, one-half of the C57BL/6 and Tacr1 KO group received one daily dose of 6 mg/kg netupitant, administered intraperitoneally, the other half of the group received saline, respectively.. Disease activity index (DAI), on the basis of stool consistency, blood and weight loss, was determined over 7 days. Histological evaluation, myeloperoxidase (MPO) measurement, cytokine concentrations and receptor expression analysis were performed on the colon samples.. NK1 receptors are up-regulated in the colon in response to DSS treatment. DSS increased DAI, histopathological scores, BLC, sICAM-1, IFN-γ, IL-16 and JE in wildtype mice, which were significantly reduced in NK1 receptor-deficient ones. NK1 receptor antagonism with netupitant significantly diminished DAI, inflammatory histopathological alterations, BLC, IFN-γ, IL-13 and IL-16 in wildtype mice, but not in the NK1-deficient ones. MPO was similarly elevated and netupitant significantly decreased its activity in both groups.. NK1 receptor antagonism could be beneficial for colitis via inhibiting different inflammatory mechanisms. Topics: Animals; Colitis; Colon; Cytokines; Dextran Sulfate; Mice; Mice, Inbred C57BL; Mice, Knockout; Neurokinin-1 Receptor Antagonists; Peroxidase; Pyridines; Receptors, Neurokinin-1; Severity of Illness Index | 2014 |
Supplementation of the diet with Salecan attenuates the symptoms of colitis induced by dextran sulphate sodium in mice.
As a water-soluble extracellular β-glucan produced by Agrobacterium sp. ZX09, Salecan has an excellent toxicological profile and exerts multiple physiological effects. The aims of the present study were to investigate the protective effects of a Salecan diet in the well-defined dextran sulphate sodium (DSS) model of experimental murine colitis and to elucidate the mechanism involved in its effects with special attention being paid to its effect on the production of TNF-α, a primary mediator involved in the inflammatory response. Male C57BL/6J mice were fed a diet supplemented with either 4 or 8 % Salecan for 26 d and DSS was administered to induce acute colitis during the last 5 d of the experimental period. Several clinical and inflammatory parameters as well as mRNA expression of TNF-α and Dectin-1 were evaluated. The results indicated that the dietary incorporation of Salecan attenuated the severity of DSS colitis as evidenced by the decreased disease activity index, reduced severity of anaemia, attenuated changes in colon architecture and reduced colonic myeloperoxidase activity. This protection was associated with the down-regulation of TNF-α mRNA levels, which might derive from its ability to increase Dectin-1 mRNA levels. In conclusion, the present study suggests that Salecan contributes to the reduction of colonic damage and inflammation in mice with DSS-induced colitis and holds promise as a new, effective nutritional supplement in the management of inflammatory bowel disease. Topics: Analysis of Variance; Animals; beta-Glucans; Colitis; Colon; Dextran Sulfate; Dietary Supplements; Disease Models, Animal; Down-Regulation; Inflammation; Intestinal Mucosa; Lectins, C-Type; Male; Mice; Mice, Inbred C57BL; Peroxidase; Real-Time Polymerase Chain Reaction; RNA, Messenger; Tumor Necrosis Factor-alpha | 2014 |
Superoxide dismutase recombinant Lactobacillus fermentum ameliorates intestinal oxidative stress through inhibiting NF-κB activation in a trinitrobenzene sulphonic acid-induced colitis mouse model.
Superoxide dismutase (SOD) can prevent and cure inflammatory bowel diseases by decreasing the amount of reactive oxygen species. Unfortunately, short half-life of SOD in the gastrointestinal tract limited its application in the intestinal tract. This study aimed to investigate the treatment effects of recombinant SOD Lactobacillus fermentum in a colitis mouse model.. In this study, we expressed the sodA gene in Lact. fermentum I5007 to obtain the SOD recombinant strain. Then, we determined the therapeutic effects of this SOD recombinant strain in a trinitrobenzene sulphonic acid (TNBS)-induced colitis mouse model. We found that SOD activity in the recombinant Lact. fermentum was increased by almost eightfold compared with that in the wild type. Additionally, both the wild type and the recombinant Lact. fermentum increased the numbers of lactobacilli in the colon of mice (P < 0·05). Colitis mice treated with recombinant Lact. fermentum showed a higher survival rate and lower disease activity index (P < 0·05). Recombinant Lact. fermentum significantly decreased colonic mucosa histological scoring for infiltration of inflammatory cells, lipid peroxidation, the expression of pro-inflammatory cytokines and myeloperoxidase (P < 0·05) and inhibited NF-κB activity in colitis mice (P < 0·05).. SOD recombinant Lact. fermentum significantly reduced oxidative stress and inflammation through inhibiting NF-κB activation in the TNBS-induced colitis model.. This study provides insights into the anti-inflammatory effects of SOD recombinant Lact. fermentum, indicating the potential therapeutic effects in preventing and curing intestinal bowel diseases. Topics: Animals; Colitis; Cytokines; Disease Models, Animal; Female; Inflammation; Intestinal Mucosa; Limosilactobacillus fermentum; Lipid Peroxidation; Mice; Mice, Inbred BALB C; NF-kappa B; Organisms, Genetically Modified; Oxidative Stress; Peroxidase; Superoxide Dismutase | 2014 |
Ginsenoside metabolite compound K promotes recovery of dextran sulfate sodium-induced colitis and inhibits inflammatory responses by suppressing NF-κB activation.
Phytogenic compounds with anti-oxidant and anti-inflammatory properties, such as ginsenoside metabolite compound K (CK) or berberine (BBR), are currently discussed as promising complementary agents in the prevention and treatment of cancer and inflammation. The latest study showed that ginsenoside Rb1 and its metabolites could inhibit TNBS-induced colitis injury. However, the functional mechanisms of anti-inflammation effects of ginsenoside, particularly its metabolite CK are still not clear. Here, using dextran sulfate sodium (DSS)-induced colitis in mice, clinical parameters, intestinal integrity, pro-inflammatory cytokines production, and signaling pathways in colonic tissues were determined. In mild and sever colitis mice, CK and BBR (as a positive agent) alleviated colitis histopathology injury, ameliorated myeloperoxidase (MPO) activity, reduced pro-inflammatory cytokines production, such as, IL-6, IL-1β, TNF-α, and increased anti-inflammatory cytokine IL-10 production in both mice colon tissues and blood. Nevertheless, the results revealed that CK and BBR inhibited NF-κB p65 nuclear translocation, downregulated p-IκBα and upregulated IκBα, indicating that CK, as well as BBR, suppressed the activation of the NF-κB pathway in the progression of colitis with immunofluorescence, immunohistochemical and western blotting analysis. Furthermore, CK inhibited pro-inflammatory cytokines production in LPS-activated macrophages via down-regulation of NF-κB signaling pathway. Taken together, our results not only reveal that CK promotes the recovery of the progression of colitis and inhibits the inflammatory responses by suppressing NF-κB activation, but also suggest that CK downregulates intestinal inflammation through regulating the activation of macrophages and pro-inflammatory cytokines production. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Berberine; Cell Line; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Inflammation Mediators; Macrophages; Mice; NF-kappa B; Peroxidase; Signal Transduction | 2014 |
Effect of glucans from Caripia montagnei mushroom on TNBS-induced colitis.
In this study, we evaluated the effect of different doses of polysaccharides extracted from Caripia montagnei mushroom at different intervals of treatment on colonic injury in the model of colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). The FT-IR analysis and NMR showed that the polysaccharides from this species of mushroom are composed of α- and β-glucans. The colonic damage was evaluated by macroscopic, histological, biochemical and immunologic analyses. The results showed the reduction of colonic lesions in all groups treated with the glucans. Such glucans significantly reduced the levels of IL-6 (50 and 75 mg/kg, p < 0.05), a major inflammatory cytokine. Biochemical analyses showed that the glucans from C. montagnei acted on reducing levels of alkaline phosphatase (75 mg/kg, p < 0.01) and myeloperoxidase (p < 0.001), a result confirmed by the reduction of cellular infiltration observed microscopically. The increase of catalase activity possibly indicates a protective effect of these glucans on colonic tissue, confirming their anti-inflammatory potential. Topics: Agaricales; Alkaline Phosphatase; Animals; Catalase; Colitis; Cytokines; Disease Models, Animal; Enzyme Activation; Glucans; Intestinal Mucosa; Male; Nitric Oxide; Nuclear Magnetic Resonance, Biomolecular; Peroxidase; Rats; Spectroscopy, Fourier Transform Infrared; Trinitrobenzenesulfonic Acid | 2014 |
Use of artificial cell microcapsule containing thalidomide for treating TNBS-induced Crohn's disease in mice.
In this study, we examined the in-vivo characteristics of a novel microencapsulated thalidomide formulation in a murine model of experimental Crohn's disease. Crohn's disease was induced with a single intra-colonic injection of 120 mg/kg of bodyweight of 2,5,6-trinitrobenzene sulfonic acid (TNBS) dissolved in 30% ethanol in Balb/c mice. Level of tumor necrosis factor alpha (TNF-α), interleukin one beta (IL-1β), interleukin 6 (IL-6) and nitric oxide (NO) were measured in tissue homogenate. Moreover, myeloperoxidase (MPO) activity was determined to assess the extent of neutrophil infiltration. Dose response study showed that treating the mice with microencapsulated thalidomide (100 mg/kg of bodyweight) for two weeks significantly decreased the degree of intestinal inflammation related to Crohn's disease. Higher and lower doses (0, 25, 50 and 200 mg/kg of bodyweight) did not exhibit comparable effects. The present study validates the success of alginate-poly-L-lysine-alginate (APA) microcapsules containing thalidomide in reducing colonic inflammation, and proposes a potential remedy for Crohn's disease. Topics: Alginates; Animals; Anti-Inflammatory Agents; Biomarkers; Capsules; Chemistry, Pharmaceutical; Colitis; Colon; Disease Models, Animal; Gastrointestinal Agents; Inflammation Mediators; Interleukin-1beta; Interleukin-6; Male; Mice; Mice, Inbred BALB C; Neutrophil Infiltration; Particle Size; Peroxidase; Polylysine; Solubility; Technology, Pharmaceutical; Thalidomide; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2014 |
Efficacy of Bifidobacterium breve NCC2950 against DSS-induced colitis is dependent on bacterial preparation and timing of administration.
Probiotics have been proposed as a therapy for inflammatory bowel disease, but variations in strains, formulations, and protocols used in clinical trials have hindered the creation of guidelines for their use. Thus, preclinical insight into the mechanisms of specific probiotic strains and mode of administration would be useful to guide future clinical trial design. In this study, live, heat inactivated (HI), and spent culture medium preparations of the probiotic Bifidobacterium breve NCC2950 were administered to specific pathogen free C57BL/6 mice before or during colitis, as well as before colitis reactivation. Five days of 3.5% dextran sulphate sodium in drinking water was used to induce colitis. Pretreatment with live B. breve reduced disease severity, myeloperoxidase activity, microscopic damage, cytokine production, interleukin (IL)-12/IL-10 ratio, and lymphocyte infiltration in the colon. B. breve did not attenuate on-going colitis. After acute colitis, disease symptoms were normalised sooner with live and HI B. breve treatment; however, reactivation of colitis was not prevented. These findings indicate that the efficacy of a probiotic to modulate intestinal inflammation is dependent on the formulation as well as state of inflammation when administered. Overall, live B. breve was most efficacious in preventing acute colitis. Live and HI B. breve also promoted recovery from diarrhoea and colon bleeding after a bout of acute colitis. Topics: Animals; Bifidobacterium; Colitis; Dextran Sulfate; Diarrhea; Inflammatory Bowel Diseases; Interleukin-10; Interleukin-12; Intestines; Male; Mice; Mice, Inbred C57BL; Peroxidase; Probiotics; Specific Pathogen-Free Organisms | 2014 |
Salvia miltiorrhiza increases the expression of transcription factor Foxp3 in experimental murine colitis.
Salvia miltiorrhiza (SM) is mainly used for the treatment of coronary heart disease in China, but previous studies demonstrated that it also shows anti‑inflammatory effects and the underlying mechanisms of these effects are not well understood. The present study aimed to investigate the effect of an injection of SM powder on the expression of transcription factor Foxp3 (Foxp3) in experimental colitis in mice. Mice were grouped and treated with SM powder for injection at the time of colonic instillation of trinitrobenzene sulfonic acid. Expression studies were performed by quantitative polymerase chain reaction and western blot analysis and histological studies were performed by hematoxylin and eosin staining. Myeloperoxidase activity was also tested for the evaluation of colitis. In the treated groups, the expression of Foxp3 mRNA and protein in the spleen were increased, the inflamed colonic lesions were relieved and the myeloperoxidase activity in the colon decreased significantly. Thus, it was demonstrated that SM exhibited its anti‑inflammatory by promoting Foxp3 expression. SM may be effective for the treatment of inflammatory disease, particularly for inflammatory bowel disease. Topics: Animals; Anti-Inflammatory Agents; Colitis; Disease Models, Animal; Female; Forkhead Transcription Factors; Gene Expression Regulation; Medicine, Chinese Traditional; Mice; Peroxidase; RNA, Messenger; Salvia miltiorrhiza; Spleen | 2014 |
Sulfated-polysaccharide fraction extracted from red algae Gracilaria birdiae ameliorates trinitrobenzenesulfonic acid-induced colitis in rats.
The aim of this study was to evaluate the protective effect of the sulfated-polysaccharide (PLS) fraction extracted from the seaweed Gracilaria birdiae in rats with trinitrobenzenesulfonic acid (TNBS)-induced colitis.. In the experiments involving TNBS-induced colitis, rats were pretreated with polysaccharide extracted from G. birdiae (PLS: 30, 60 and 90 mg/kg, 500 μL p.o.) or dexamethasone (control group: 1 mg/kg) once daily for 3 days starting before TNBS instillation (day 1). The rats were killed on the third day, the portion of distal colon was excised and washed with 0.9% saline and pinned onto a wax block for the evaluation of macroscopic scores. Samples of the intestinal tissue were used for histological evaluation and assays for glutathione (GSH) levels, malonyldialdehyde (MDA) concentration, myeloperoxidase (MPO) activity, nitrate and nitrite (NO3 /NO2 ) concentration and cytokines levels.. PLS treatment reduced the macroscopic and microscopic TNBS-induced intestinal damage. Additionally, it avoided the consumption of GSH, decreased pro-inflammatory cytokine levels, MDA and NO3 /NO2 concentrations and diminished the MPO activity.. Our results suggest that the PLS fraction has a protective effect against intestinal damage through mechanisms that involve the inhibition of inflammatory cell infiltration, cytokine releasing and lipid peroxidation. Topics: Animals; Colitis; Colon; Cytokines; Dexamethasone; Glutathione; Gracilaria; Inflammation; Lipid Peroxidation; Male; Malondialdehyde; Nitrates; Nitrites; Peroxidase; Polysaccharides; Rats; Rats, Wistar; Rhodophyta; Trinitrobenzenesulfonic Acid | 2014 |
Neutrophil elastase inhibitor suppresses IL-17 based inflammation of murine experimental colitis.
Neutrophil elastase (NE) is a proteinase in granulocytes and plays an important role in the pathogenesis of inflammatory disorders. It has been reported that NE activity is elevated in both colonic mucosa and blood in inflammatory bowel disease (IBD) patients, and that it can act as an aggravating factor in IBD. To develop novel therapies for IBD, we examined the effects of an NE inhibitor, Elaspor®, on murine experimental colitis.. Acute colitis was induced in BALB/c mice by administration of dextran sulfate sodium (DSS) in drinking water for 7 days. NE inhibitor was administered subcutaneously to mice prior to and during the induction of colitis. Disease activity index (DAI), colonic myeloperoxidase (MPO) activity, luminal NE activity, and mRNA expression in the colon were then investigated.. Subcutaneous administration of NE inhibitor ameliorated the severity of DSS-induced colitis. NE activity was elevated in inflamed colon, and was reduced by NE inhibitor administration. mRNA expression levels of IL-17, a Th17-based inflammatory factor, was also decreased in the colon of NE inhibitor-administered mice.. These results suggest that NE inhibitor ameliorated colonic inflammation by decreasing both the activity of NE and the effects of cytokine balance. Clinically, NE inhibitor improves injuries associated with systemic inflammatory response syndrome. Similarly, clinical use of this inhibitor would further clarify its usefulness in clinical colonic inflammation. Topics: Animals; Chemokines; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Female; Glycine; Interleukin-17; Leukocyte Elastase; Mice; Mice, Inbred BALB C; Peroxidase; Proteinase Inhibitory Proteins, Secretory; RNA, Messenger; Sulfonamides | 2014 |
Anti-inflammatory effect of recreational exercise in TNBS-induced colitis in rats: role of NOS/HO/MPO system.
There are opposite views in the available literature: Whether physical exercise has a protective effect or not on the onset of inflammatory bowel disease (IBD). Therefore, we investigated the effects of recreational physical exercise before the induction of colitis. After 6 weeks of voluntary physical activity (running wheel), male Wistar rats were treated with TNBS (10 mg). 72 hrs after trinitrobenzene sulphonic acid (TNBS) challenge we measured colonic gene (TNF-α, IL-1β, CXCL1 and IL-10) and protein (TNF-α) expressions of various inflammatory mediators and enzyme activities of heme oxygenase (HO), nitric oxide synthase (NOS), and myeloperoxidase (MPO) enzymes. Wheel running significantly increased the activities of HO, constitutive NOS (cNOS) isoform. Furthermore, 6 weeks of running significantly decreased TNBS-induced inflammatory markers, including extent of lesions, severity of mucosal damage, and gene expression of IL-1β, CXCL1, and MPO activity, while IL-10 gene expression and cNOS activity were increased. iNOS activity decreased and the activity of HO enzyme increased, but not significantly, compared to the sedentary TNBS-treated group. In conclusion, recreational physical exercise can play an anti-inflammatory role by downregulating the gene expression of proinflammatory mediators, inducing anti-inflammatory mediators, and modulating the activities of HO and NOS enzymes in a rat model of colitis. Topics: Animals; Anti-Inflammatory Agents; Body Weight; Colitis; Colon; Gene Expression Profiling; Heme Oxygenase (Decyclizing); Inflammation Mediators; Intestinal Mucosa; Male; Nitric Oxide Synthase; Peroxidase; Physical Conditioning, Animal; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2014 |
Andrographolide sulfonate ameliorates experimental colitis in mice by inhibiting Th1/Th17 response.
Inflammatory bowel disease (IBD) is a chronic, relapsing and remitting condition of inflammation involves overproduction of pro-inflammatory cytokines and excessive functions of inflammatory cells. However, current treatments for IBD may have potential adverse effects including steroid dependence, infections and lymphoma. Therefore new therapies for the treatment of IBD are desperately needed. In the present study, we aimed to examine the effect of andrographolide sulfonate, a water-soluble form of andrographolide (trade name: Xi-Yan-Ping Injection), on murine experimental colitis induced by 2, 4, 6-trinitrobenzene sulfonic acid (TNBS). Andrographolide sulfonate was administrated through intraperitoneal injection to mice with TNBS-induced colitis. TNBS-induced body weight loss, myeloperoxidase activity, shortening of the colon and colonic inflammation were significantly ameliorated by andrographolide sulfonate. Both the mRNA and protein levels of pro-inflammatory cytokines were reduced by andrographolide sulfonate administration. Moreover, andrographolide sulfonate markedly suppressed the activation of p38 mitogen-activated protein kinase as well as p65 subunit of nuclear factor-κB (NF-κB). Furthermore, CD4(+) T cell infiltration as well as the differentiation of Th1 (CD4(+)IFN-γ(+)) and Th17 (CD4(+)IL17A(+)) subset were inhibited by andrographolide sulfonate. In summary, these results suggest that andrographolide sulfonate ameliorated TNBS-induced colitis in mice through inhibiting Th1/Th17 response. Our study shows that water-soluble andrographolide sulfonate may represent a new therapeutic approach for treating gastrointestinal inflammatory disorders. Topics: Alkanesulfonates; Animals; Body Weight; Colitis; Colon; Cytokines; Diterpenes; Injections, Intraperitoneal; Mice; Mice, Inbred C57BL; Models, Animal; NF-kappa B; p38 Mitogen-Activated Protein Kinases; Peroxidase; Signal Transduction; Th1 Cells; Th17 Cells; Trinitrobenzenesulfonic Acid | 2014 |
Hepcidin expression in colon during trinitrobenzene sulfonic acid-induced colitis in rats.
To investigate hepcidin expression, interleukin-6 (IL-6) production and iron levels in the rat colon in the presence of trinitrobenzene sulfonic acid (TNBS)-induced colitis.. In rats, we evaluated the severity of colitis induced by repeated TNBS administration using macroscopic and microscopic scoring systems and myeloperoxidase activity measurements. The colonic levels of hepcidin, tumor necrosis factor alpha (TNF-α), IL-10 and IL-6 were measured by Enzyme-Linked Immunosorbent Assay, and hepcidin-25 expression and iron deposition were analyzed by immunohistochemistry and the Prussian blue reaction, respectively. Stat-3 phosphorylation was assessed by Western blot analysis. Hematological parameters, iron and transferrin levels, and transferrin saturation were also measured. Additionally, the ability of iron, pathogen-derived molecules and IL-6 to induce hepcidin expression in HT-29 cells was evaluated.. Repeated TNBS administration to rats resulted in macroscopically and microscopically detectable colon lesions and elevated colonic myeloperoxidase activity. Hepcidin-25 protein levels were increased in colonic surface epithelia in colitic rats (10.2 ± 4.0 pg/mg protein vs 71.0 ± 8.4 pg/mg protein, P < 0.01). Elevated IL-6 levels (8.2 ± 1.7 pg/mg protein vs 14.7 ± 0.7 pg/mg protein, P < 0.05), TNF-α levels (1.8 ± 1.2 pg/mg protein vs 7.4 ± 2.1 pg/mg protein, P < 0.05) and Stat-3 phosphorylation were also observed. Systemic alterations in iron homeostasis, hepcidin levels and anemia were not detected in colitic rats. Iron deposition in the colon was only observed during colitis. Hepcidin gene expression was increased in HT-29 cells after IL-6 and lipopolysaccharide [a toll-like receptor 4 (TLR-4) ligand] treatment. Deferoxamine, ferric citrate and peptidoglycan (a TLR-2 ligand) were unable to alter the in vitro expression of hepcidin in HT-29 cells.. Colitis increased local hepcidin-25 expression, which was associated with the IL-6/Stat-3 signaling pathway. An increase in local iron sequestration was also observed, but additional studies are needed to determine whether this sequestration is a defensive or pathological response to intestinal inflammation. Topics: Animals; Colitis; Colon; Enzyme-Linked Immunosorbent Assay; Gene Expression Profiling; Gene Expression Regulation; Hepcidins; Interleukin-10; Interleukin-6; Iron; Male; Peroxidase; Phosphorylation; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2014 |
Camel's milk ameliorates TNBS-induced colitis in rats via downregulation of inflammatory cytokines and oxidative stress.
Current treatment strategies for inflammatory bowel diseases (IBD) are associated with several adverse effects, and thus, the search for effective agents with minimal side effects merits attention. Camel's milk (CM) is endowed with antioxidant/anti-inflammatory features and has been reported to protect against diabetes and hepatic injury, however, its effects on IBD have not been previously explored. In the current study, we aimed to investigate the potential alleviating effects of CM against TNBS-induced colitis in rats. CM (10 ml/kg b.i.d. by oral gavage) effectively suppressed the severity of colon injury as evidenced by amelioration of macroscopic damage, colon weight/length ratio, histopathological alterations, leukocyte influx and myeloperoxidase activity. Administration of CM mitigated the colonic levels of TNF-α and IL-10 cytokines. The attenuation of CM to colon injury was also associated with suppression of oxidative stress via reduction of lipid peroxides and nitric oxide along with boosting the antioxidant defenses through restoration of colon glutathione and total anti-oxidant capacity. In addition, caspases-3 activity, an apoptotic marker, was inhibited. Together, our study highlights evidences for the promising alleviating effects of CM in colitis. Thus, CM may be an interesting complementary approach for the management of IBD. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Camelus; Caspase 3; Caspase Inhibitors; Colitis; Cytokines; Down-Regulation; Interleukin-10; Leukocytes; Milk; Oxidative Stress; Peroxidase; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2014 |
Estrous cycle dependent fluctuations of regulatory neuropeptides in the lower urinary tract of female rats upon colon-bladder cross-sensitization.
Co-morbidity of bladder, bowel, and non-specific pelvic pain symptoms is highly prevalent in women. Little evidence is present on modulation of pelvic pain syndromes by sex hormones, therefore, the objective of this study was to clarify the effects of hormonal fluctuations within the estrous cycle on regulatory neuropeptides in female rats using a model of neurogenic bladder dysfunction. The estrous cycle in female rats (Sprague-Dawley, 230-250 g) was assessed by vaginal smears and weight of uterine horns. Neurogenic bladder dysfunction was induced by a single inflammatory insult to the distal colon. Protein expression of calcitonin gene related peptide (CGRP), substance P (SP), nerve growth factor (NGF), and brain derived neurotrophic factor (BDNF) in the pelvic organs, sensory ganglia and lumbosacral spinal cord was compared in rats in proestrus (high estrogen) vs diestrus (low estrogen). Under normal physiological conditions, concentration of SP and CGRP was similar in the distal colon and urinary bladder during all phases of the estrous cycle, however, acute colitis induced a significant up-regulation of CGRP content in the colon (by 63%) and urinary bladder (by 54%, p≤0.05 to control) of rats in proestrus. These changes were accompanied by a significant diminution of CGRP content in L6-S2 DRG after colonic treatment, likely associated with its release in the periphery. In rats with high estrogen at the time of testing (proestrus), experimental colitis caused a significant up-regulation of BDNF colonic content from 26.1±8.5 pg/ml to 83.4±32.5 pg/ml (N = 7, p≤0.05 to control) and also induced similar effects on BDNF in the urinary bladder which was also up-regulated by 5-fold in rats in proestrus (p≤0.05 to respective control). Our results demonstrate estrous cycle dependent fluctuations of regulatory neuropeptides in the lower urinary tract upon colon-bladder cross-sensitization, which may contribute to pain fluctuations in female patients with neurogenic bladder pain. Topics: Animals; Brain-Derived Neurotrophic Factor; Calcitonin Gene-Related Peptide; Colitis; Colon; Estrous Cycle; Female; Ganglia, Spinal; Gonadal Steroid Hormones; Nerve Growth Factors; Neuropeptides; Peroxidase; Rats; Substance P; Urinary Bladder | 2014 |
Lactobacillus plantarum CLP-0611 ameliorates colitis in mice by polarizing M1 to M2-like macrophages.
The TNF-α expression-inhibitory effect of lactic acid bacteria (LAB) isolated from kimchi were measured in lipopolysaccharide (LPS)-stimulated peritoneal macrophages. Among the LAB evaluated, Lactobacillus plantarum CLP-0611 inhibited the IL-1β and IL-6 expression, as well as the NF-κB and AP1 activation in LPS-stimulated peritoneal macrophages. Therefore, we investigated its inhibitory effect on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. TNBS significantly induced colon shortening, as well as myeloperoxidase activity and macroscopic score. Oral administration of CLP-0611 significantly reduced TNBS-induced body weight loss, colon shortening, myeloperoxidase activity, IRAK-1 phosphorylation, NF-κB and MAP kinase (p38, ERK, JNK) activation, and iNOS and COX-2 expression. CLP-0611 also inhibited TNBS-induced expression of TNF-α, IL-1β, and IL-6. However, IL-10 expression was induced. CLP-0611 also induced the production of M2 macrophage markers (IL-10, arginase I and CD206). Based on these findings, CLP-0611 inhibits TLR-4-linked NF-κB and MAPK signaling pathways and polarizes M1 to M2-like macrophages, thus ameliorating colitis. Topics: Administration, Oral; Animals; Cell Differentiation; Cells, Cultured; Colitis; Colon; Cytokines; Interleukin-1 Receptor-Associated Kinases; Lactobacillus plantarum; Lipopolysaccharides; Macrophages, Peritoneal; Male; MAP Kinase Signaling System; Mice; Mice, Inbred ICR; NF-kappa B; Peroxidase; Probiotics; Transcription Factor AP-1; Trinitrobenzenesulfonic Acid | 2014 |
Ameliorative potential of aliskiren in experimental colitis in mice.
In the present study, we investigated the ameliorative potential of aliskiren in dextran sulfate sodium (DSS) induced colitis in mice. Aliskiren (3 and 10mg/kg, i.p.) was administered for 10 days from the day of DSS administration. The severity of colitis in mice was assessed using body weight loss, colon and spleen weight, hematological parameters, food intake, stool consistency, rectal bleeding and colon shortening. Colonic malondialdehyde (MDA), myeloperoxidase (MPO) and renin mRNA levels were also estimated. Furthermore, TNF-α and IL-6 in plasma and colon were analyzed. The results showed that aliskiren (10mg/kg, i.p.) significantly improved the severity of colitis by, decrease in weight loss, improvement in food intake and stool consistency, decrease in rectal bleeding, decrease in relative colon and spleen weight and improvement in colonic shortening. Aliskiren (10mg/kg, i.p.) improved blood hemoglobin, red blood cells (RBC) and hematocrit. Colonic malondialdehyde (MDA), MPO and histolopathological score were significantly diminished by aliskiren (10mg/kg, i.p.). Furthermore, aliskiren (10mg/kg, i.p.) significantly diminished the elevated levels of TNF-α, IL-6 and renin mRNA in inflammed colon. These results indicate involvement of renin in colitis and inhibition of renin by aliskiren ameliorates colitis. Topics: Amides; Animals; Anti-Inflammatory Agents; Antioxidants; Body Weight; Colitis; Colon; Cytokines; Dextran Sulfate; Eating; Erythrocytes; Female; Fumarates; Gene Expression Regulation; Hematocrit; Hemoglobins; Malondialdehyde; Mice; Organ Size; Peroxidase; Renin; RNA, Messenger; Spleen | 2014 |
Oral administration of Lactobacillus paracasei alleviates clinical symptoms of colitis induced by dextran sulphate sodium salt in BALB/c mice.
The aim of this study was to investigate the alleviating effect of Lactobacillus paracasei subsp. paracasei LC-01 (LC-01) on the murine model of colitis induced by dextran sulphate sodium (DSS). 50 pathogen-free, 6-week-old male BALB/c mice were divided randomly into 5 groups, including a control group and four DSS-LC-01-treated groups (DSS, DSS-106, DSS-108, and DSS-1010 with 0, 1×106, 1×108 and 1×1010 cfu/ml LC-01, respectively). To test the effectiveness of LC-01 as a prophylactic it was administered for 7 days before the onset of the disease in DSS-LC-01-treated mice. After 7 days, colitis was induced by administration of 2.5% (w/v) DSS in drinking water for a further 7 days. The disease activity index (DAI), histological score, myeloperoxidase (MPO) activity and the level of the pro-inflammatory cytokines interleukin-1β (IL-1β) and tumour necrosis factor α (TNF-α) were measured. DAI, histological scores and MPO activity of mice treated with a medium or high dose of LC-01 were significantly lower compared to a low-dose of LC-01 and DSS treatment alone (P<0.05). Colon length shortening could be prevented with increasing dose of LC-01. In addition, the levels of IL-1β and TNF-α were suppressed significantly by treatment with a medium and high dose of LC-01. However, no significant difference in the indices mentioned above were observed between a low dose of LC-01 and treatment with DSS alone (P≯0.05). An appropriate dose of LC-01 can prevent intestinal damage in mice with DSS-induced colitis. The expression of inflammatory cytokines related to pathogenesis of DSS-induced colitis decreased following treatment with LC-01. Topics: Administration, Oral; Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Feces; Inflammation; Interleukin-1beta; Intestinal Mucosa; Lactobacillus; Male; Mice; Mice, Inbred BALB C; Peroxidase; Probiotics; Tumor Necrosis Factor-alpha | 2014 |
Monocolonization of germ-free mice with Bacteroides fragilis protects against dextran sulfate sodium-induced acute colitis.
Ulcerative colitis is inflammatory conditions of the colon caused by interplay of genetic and environmental factors. Previous studies indicated that the gut microflora may be involved in the colonic inflammation. Bacteroides fragilis (BF) is a Gram-negative anaerobe belonging to the colonic symbiotic. We aimed to investigate the protective role of BF in a colitis model induced in germ-free (GF) mice by dextran sulfate sodium (DSS). GF C57BL/6JNarl mice were colonized with BF for 28 days before acute colitis was induced by DSS. BF colonization significantly increased animal survival by 40%, with less reduction in colon length, and decreased infiltration of inflammatory cells (macrophages and neutrophils) in colon mucosa following challenge with DSS. In addition, BF could enhance the mRNA expression of anti-inflammatory-related cytokine such as interleukin 10 (IL-10) with polymorphism cytokine IL-17 and diminish that of proinflammatory-related tumor necrosis factor α with inducible nitric oxide synthase in the ulcerated colon. Myeloperoxidase activity was also decreased in BF-DSS mice. Taking these together, the BF colonization significantly ameliorated DSS-induced colitis by suppressing the activity of inflammatory-related molecules and inducing the production of anti-inflammatory cytokines. BF may play an important role in maintaining intestinal immune system homeostasis and regulate inflammatory responses. Topics: Acute Disease; Animals; Bacteroides fragilis; Blood Cell Count; Colitis; Colon; Colony Count, Microbial; Dextran Sulfate; Gene Expression Regulation; Germ-Free Life; Inflammation; Kaplan-Meier Estimate; Male; Mice, Inbred C57BL; Peroxidase; Real-Time Polymerase Chain Reaction | 2014 |
Role of HMGB1 as a suitable biomarker of subclinical intestinal inflammation and mucosal healing in patients with inflammatory bowel disease.
Noninvasive biomarkers of high- and low-grade intestinal inflammation and of mucosal healing (MH) in patients with inflammatory bowel disease are currently lacking. We have recently shown that fecal high mobility group box 1 (HMGB1) protein is a novel biomarker of gut inflammation. We aimed at investigating in a mouse model if HMGB1 was able to foresee both a clinically evident and a subclinical gut inflammation and if its normalization indicated MH. We also aimed at confirming the results in patients with Crohn's disease (CD) and ulcerative colitis.. C57BL6/J mice were treated with increasing doses of dextran sodium sulphate to induce colitis of different severity degrees; 28 with CD, 23 with ulcerative colitis, and 17 controls were also enrolled. Fecal HMGB1 was analyzed by enzyme-linked immunosorbent assay and immunoblotting.. Fecal HMGB1 increased by 5-, 11-, 18-, and 24-folds with dextran sodium sulphate doses of 0.25%, 0.50%, 1%, and 4%, respectively, showing that the protein detected a high-grade and a subclinical inflammation. After a recovery time of 4-week posttreatment, HMGB1 returned to control levels, paralleling MH. In patients, fecal HMGB1 significantly correlated with endoscopic indexes (Simple Endoscopic Score for Crohn's Disease [SES-CD], endoscopic Mayo subscore), but not with the disease activity indexes (Crohn's disease Activity Index, partial Mayo score).. Fecal HMGB1 is a robust noninvasive biomarker of clinically overt and subclinical gut inflammation; it can also be a surrogate marker of MH. We suggest the use of fecal HMGB1 to monitor the disease course and assess therapy outcomes in inflammatory bowel disease. Topics: Adult; Aged; Animals; Biomarkers; Blotting, Western; Case-Control Studies; Cells, Cultured; Colitis; Colitis, Ulcerative; Crohn Disease; Dextran Sulfate; Disease Progression; Double-Blind Method; Enzyme-Linked Immunosorbent Assay; Feces; Female; Follow-Up Studies; HMGB1 Protein; Humans; Inflammation; Intestinal Mucosa; Male; Mice; Mice, Inbred C57BL; Middle Aged; Peroxidase; Prognosis; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Wound Healing; Young Adult | 2014 |
All-trans retinoic acid attenuates experimental colitis through inhibition of NF-κB signaling.
Inflammatory bowel disease (IBD) is characterized by excessive innate immune cell activation, which is responsible for tissue damage and induction of adaptive immune responses. All-trans retinoic acid (ATRA), the ligand of retinoic acid receptors (RAR), has been previously shown to regulate adaptive immune responses and restore Th17/Treg balance, while its role in regulation of innate immune cell function such as macrophages remains to be elucidated. The study was performed to explore the effect of ATRA on regulation of innate immune responses during dextran sulfate sodium (DSS) induced murine colitis. The mice with DSS colitis were administered with vehicle, ATRA, or LE135. Colitis was evaluated by clinical symptoms, tissue myeloperoxidase (MPO) activity, and the expressions of CD68 and nuclear factor (NF) κB p65, and tumor necrosis factor (TNF) level in inflamed colon. RAW 264.7 cells were pretreated with vehicle, ATRA, or LE135, followed by LPS challenge in vitro. ATRA administration ameliorates DSS-induced colitis evidenced with decreased TNF level and CD68 expression, while LE135 leads to exacerbation of colitis. ATRA treatment in vitro dampens LPS induced NF-κB activation and TNF production of RAW 264.7 cells. Together, our data show a crucial role of ATRA in the progress of acute colitis through inhibiting NF-κB activation, and suggest that ATRA represents a novel therapeutic approach for the management of IBD. Topics: Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Cell Line; Colitis; Dextran Sulfate; Disease Models, Animal; Female; Lipopolysaccharides; Macrophages; Mice; Neutrophil Infiltration; NF-kappa B; Peroxidase; Signal Transduction; Tretinoin; Tumor Necrosis Factors | 2014 |
Mast cell deficiency exacerbates inflammatory bowel symptoms in interleukin-10-deficient mice.
To test the role of mast cells in gut inflammation and colitis using interleukin (IL)-10-deficient mice as an experimental model.. Mast cell-deficient (Kit (W-sh/W-sh) ) mice were crossbred with IL-10-deficient mice to obtain double knockout (DKO) mice. The growth, mucosal damage and colitis status of DKO mice were compared with their IL-10-deficient littermates.. DKO mice exhibited exacerbated colitis compared with their IL-10-deficient littermates, as shown by increased pathological score, higher myeloperoxidase content, enhanced Th1 type pro-inflammatory cytokines and inflammatory signaling, elevated oxidative stress, as well as pronounced goblet cell loss. In addition, deficiency in mast cells resulted in enhanced mucosal damage, increased gut permeability, and impaired epithelial tight junctions. Mast cell deficiency was also linked to systemic inflammation, as demonstrated by higher serum levels of tumor necrosis factor α and interferon γ in DKO mice than that in IL-10-deficient mice.. Mast cell deficiency in IL-10-deficient mice resulted in systematic and gut inflammation, impaired gut barrier function, and severer Th1-mediated colitis when compared to mice with only IL-10-deficiency. Inflammation and impaired gut epithelial barrier function likely form a vicious cycle to worsen colitis in the DKO mice. Topics: Animals; Colitis; Colon; Disease Models, Animal; Feces; Genotype; Inflammation Mediators; Inflammatory Bowel Diseases; Interferon-gamma; Interleukin-10; Intestinal Mucosa; Male; Mast Cells; Mice, Inbred C57BL; Mice, Knockout; Oxidative Stress; Peroxidase; Phenotype; Proto-Oncogene Proteins c-kit; Signal Transduction; Th1 Cells; Time Factors; Tumor Necrosis Factor-alpha | 2014 |
Preventive effects of Escherichia coli strain Nissle 1917 with different courses and different doses on intestinal inflammation in murine model of colitis.
To analyze the in vivo effect of Escherichia coli Nissle 1917 (EcN) with different courses and different doses to Sprague-Dawley rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis.. The probiotic was orally administered with different courses of treatment (with or without pre-administration) and different doses (10(7)-10(9) CFU/day) to Sprague-Dawley rats with TNBS-induced colitis. Therapeutic effects, levels of cytokine in serum, mRNA and protein expression were analyzed.. Oral EcN administration after TNBS-induced improved colitis dose dependently. In parallel, a reduction of disease activity index and colonic MPO activity together with a decreased level of TNF-α and a trend of increased IL-10 expression was detected. Pre-administration of 10(7)CFU/day EcN to TNBS-treated rats resulted in a significant protection against inflammatory response and colons isolated from these rats exhibited a more pronounced expression of ZO-1 than the other groups. In the group of pre-administration of 10(9)CFU/day, the condition was not improved but deteriorated.. This study convincingly demonstrates that pre-administration of probiotic EcN with low dose is able to protect colitis of rats and mediate up-regulation of ZO-1 expression, but long-term of high-dose EcN may do harm to colitis. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Disease Models, Animal; Escherichia coli; Female; Ileum; Interleukin-10; Intestinal Mucosa; Peroxidase; Probiotics; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Zonula Occludens-1 Protein | 2014 |
Impaired hydrogen sulfide synthesis and IL-10 signaling underlie hyperhomocysteinemia-associated exacerbation of colitis.
Vitamin B deficiencies, which can lead to hyperhomocysteinemia (Hhcy), are commonly reported in patients with inflammatory bowel disease (IBD) and may be a causative underlying factor. However, the mechanism for this effect is not known. Hydrogen sulfide (H2S) is a gaseous mediator that promotes tissue repair and resolution of inflammation. In experimental colitis, a marked increase in colonic H2S synthesis drives ulcer healing and resolution of inflammation. Because H2S synthesis is in part dependent upon enzymes that require vitamin B6 as a cofactor, we tested the hypothesis that Hhcy in rodent models would increase the susceptibility to colitis. In all three models tested, diet-induced Hhcy significantly exacerbated colitis. The usual elevation of colonic H2S synthesis after induction of colitis was absent in all three models of colitis. Administration of an H2S donor to Hhcy rats significantly decreased the severity of colitis. Compared with wild-type mice, interleukin (IL) 10-deficient mice on a normal diet had decreased levels of colonic H2S synthesis, a 40% increase in serum homocysteine, and a phenotype similar to wild-type mice with Hhcy. IL-10-deficient mice fed the vitamin B-deficient diet exhibited more severe colonic inflammation, but the normal elevation of colonic H2S synthesis was absent. Administration of IL-10 to the IL-10-deficient mice restored colonic H2S synthesis and significantly decreased serum homocysteine levels. These results suggest that the exacerbation of colitis in Hhcy is due in part to impaired colonic H2S synthesis. Moreover, IL-10 plays a novel role in promoting H2S production and homocysteine metabolism, which may have therapeutic value in conditions characterized by Hhcy. Topics: Animals; Colitis; Colon; Dextran Sulfate; Diet; Disease Progression; Humans; Hydrogen Sulfide; Hyperhomocysteinemia; Interleukin-10; Male; Mice, Inbred C57BL; Peroxidase; Rats, Wistar; Recombinant Proteins; Signal Transduction | 2014 |
Preventive effect of the microalga Chlamydomonas debaryana on the acute phase of experimental colitis in rats.
Inflammatory bowel diseases (IBD) are characterised by chronic uncontrolled inflammation of intestinal mucosa. Diet and nutritional factors have emerged as possible interventions for IBD. Microalgae are rich sources of n-3 PUFA and derived oxylipins. Oxylipins are lipid mediators involved in the resolution of many inflammatory disorders. The aim of the present study was to investigate the effects of the oxylipin-containing biomass of the microalga Chlamydomonas debaryana and its major oxylipin constituent, (9Z,11E,13S,15Z)-13-hydroxyoctadeca-9,11,15-trienoic acid ((13S)-HOTE), on acute 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats. Lyophilised microalgal biomass and (13S)-HOTE were administered by oral route 48, 24 and 1 h before the induction of colitis and 24 h later, and the rats were killed after 48 h. The treatment with the lyophilised microalga and (13S)-HOTE improved body-weight loss and colon shortening, as well as attenuated the extent of colonic damage and increased mucus production. Cellular neutrophil infiltration, with the subsequent increase in myeloperoxidase levels induced by TNBS, were also reduced after the administration of the lyophilised microalga or (13S)-HOTE. The anti-inflammatory effects of these treatments were confirmed by the inhibition of colonic TNF-α production. Moreover, lyophilised microalga or (13S)-HOTE down-regulated cyclo-oxygenase-2 and inducible nitric oxide synthase expression. The present study was the first to show the prophylactic effects of a lyophilised biomass sample of the microalga C. debaryana and the oxylipin (13S)-HOTE on TNBS-induced acute colitis in rats. Our findings suggest that the microalga C. debaryana or derived oxylipins could be used as nutraceuticals in the treatment of the active phase of IBD. Topics: Animals; Anti-Inflammatory Agents; Biomass; Chlamydomonas; Colitis; Colon; Cyclooxygenase 2; Fatty Acids, Omega-3; Freeze Drying; Linoleic Acids; Male; Neutrophils; Nitric Oxide Synthase Type II; Oxylipins; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2014 |
Rutin has intestinal antiinflammatory effects in the CD4+ CD62L+ T cell transfer model of colitis.
Rutin, one of the most abundant flavonoids in nature, has been shown to exert intestinal antiinflammatory effects in experimental models of colitis. Our aim was to study the antiinflamatory effect of rutin in the CD4+ CD62L+ T cell transfer model of colitis, one of the closest to the human disease. Colitis was induced by transfer of CD4+ CD62L+ T cells to Rag1(-/-) mice. Rutin was administered by gavage as a postreatment. Treatment with rutin improved colitis at the dose of 57mg/kg/day, while no effect was noted with 28.5mg/kg/day. Therapeutic benefit was evidenced by a reduced disease activity index, weight loss and damage score, plus a 36% lower colonic myeloperoxidase and a 54% lower alkaline phosphatase activity. In addition, a decreased secretion of proinflammatory cytokines (IFNγ and TNFα) by mesenteric lymph node cells was observed ex vivo. The colonic expression of proinflammatory genes, including IFNγ, TNFα, CXCL1, S100A8 and IL-1β, was significantly reduced by more than 80% with rutin as assessed by RT-qPCR. Flavonoid treated mice exhibited decreased activation of splenic CD4+ cells (STAT4 phosphorylation and IFNγ expression) and reduced plasma cytokine levels. This effect was also apparent in mucosal lymphocytes based on reduced STAT4 phosphorylation. The protective effect was comparable to that of 3mg/kg/day budesonide. Rutin had no effect on splenocytes or murine T cells in vitro, while its aglycone, quercetin, exhibited a concentration dependent inhibition of proinflammatory cytokines, including IFNγ. Rutin but not quercetin showed vectorial basolateral to apical transport in IEC18 cells, associated with reduced biotransformation. We conclude that rutin exerts intestinal antiinflammatory activity in chronic, T lymphocyte dependent colitis via quercetin release and actions involving mucosal and lymph node T cells. Our results suggest that rutin may be useful in the management of inflammatory bowel disease in appropriate dosage conditions. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Cell Line; Cells, Cultured; Colitis; Cytokines; Disease Models, Animal; Female; Homeodomain Proteins; Intestine, Large; Lymph Nodes; Mice, Inbred C57BL; Mice, Knockout; NF-kappa B; Peroxidase; Quercetin; Rats, Wistar; RNA, Messenger; Rutin; Spleen; STAT4 Transcription Factor; T-Lymphocytes | 2014 |
Inhibition of the dephosphorylation of eukaryotic initiation factor 2α ameliorates murine experimental colitis.
Endoplasmic reticulum (ER) stress in the intestine is closely associated with the development of inflammatory bowel disease (IBD). However, the role of the protein kinase RNA-like ER kinase in this disease is not fully known. We studied whether an inhibitor of the dephosphorylation of eukaryotic initiation factor 2α, salubrinal, improves murine experimental colitis through the amelioration of ER stress.. Colitis was induced by the administration of 3% dextran sulfate sodium (DSS) for 5 days. Mice were injected salubrinal intraperitoneally from the commencement of DSS treatment and were sacrificed on day 10. The severity of colitis was evaluated histologically using a scoring system.Myeloperoxidase activity and the expression of proinflammatory cytokine genes in the colon were analyzed. The expression levels of ER stress-related proteins were evaluated by Western blotting.. The administration of salubrinal significantly attenuated body weight loss and improved colitis, as assessed histologically. The elevation of myeloperoxidase activity and the expression of proinflammatory cytokine genes were suppressed in salubrinal-treated mice. The expression of glucose-regulated protein 78, activating translation factor 4, and heat-shock protein 70 was elevated in mice treated with salubrinal.. The amelioration of ER stress may be a therapeutic target for the treatment of IBD. Topics: Animals; Cinnamates; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; DNA-Binding Proteins; eIF-2 Kinase; Endoplasmic Reticulum Chaperone BiP; Endoplasmic Reticulum Stress; Eukaryotic Initiation Factor-2; Heat-Shock Proteins; HSP70 Heat-Shock Proteins; Injections, Intraperitoneal; Interleukins; Male; Mice; Mice, Inbred C57BL; Peroxidase; Regulatory Factor X Transcription Factors; RNA, Messenger; Thiourea; Transcription Factors; Tumor Necrosis Factor-alpha; Weight Loss | 2014 |
Maternal exposure to low levels of corticosterone during lactation protects against experimental inflammatory colitis-induced damage in adult rat offspring.
Opposing emotional events (negative/trauma or positive/maternal care) during the postnatal period may differentially influence vulnerability to the effects of stress later in life. The development and course of intestinal disorders such as inflammatory bowel disease are negatively affected by persistent stress, but to date the role of positive life events on these pathologies has been entirely unknown. In the present study, the effect of early life beneficial experiences in the development of intestinal dysfunctions, where inflammation and stress stimuli play a primary role, was investigated. As a "positive" experimental model we used adult male rat progeny nursed by mothers whose drinking water was supplemented with moderate doses of corticosterone (CORT) (0.2 mg/ml) during the lactation period. Such animals have been generally shown to cope better with different environmental situations during life. The susceptibility to inflammatory experimental colitis induced by intracolonic infusion of TNBS (2,4,6-trinitrobenzenesulphonic acid) was investigated in CORT-nursed rats in comparison with control rats. This mild increase in maternal corticosterone during lactation induced, in CORT-nursed rats, a long lasting protective effect on TNBS-colitis, characterized by improvements in some indices of the disease (increased colonic myeloperoxidase activity, loss of body weight and food intake) and by the involvement of endogenous peripheral pathways known to participate in intestinal disorder development (lower plasma corticosterone levels and colonic mast cell degranulation, alterations in the colonic expression of both corticotrophin releasing factor/CRF and its receptor/CRH-1R). All these findings contribute to suggesting that the reduced vulnerability to TNBS-colitis in CORT-nursed rats is due to recovery from the colonic mucosal barrier dysfunction. Such long lasting changes induced by mild hormonal manipulation during lactation, making the adult also better adapted to colonic inflammatory stress, constitute a useful experimental model to investigate the etiopathogenetic mechanisms and therapeutic treatments of some gastrointestinal diseases. Topics: Animals; Animals, Newborn; Blotting, Western; Body Weight; Chymases; Colitis; Colon; Corticosterone; Corticotropin-Releasing Hormone; Eating; Female; Immunohistochemistry; Lactation; Male; Peroxidase; Protective Agents; Rats, Wistar; Receptors, Corticotropin-Releasing Hormone; Trinitrobenzenesulfonic Acid | 2014 |
Partial replacement of dietary linoleic acid with long chain n-3 polyunsaturated fatty acids protects against dextran sulfate sodium-induced colitis in rats.
Imbalances in the dietary n-6 and n-3 polyunsaturated fatty acids have been implicated in the increased prevalence of inflammatory bowel disease. This study investigated the effects of substitution of linoleic acid with long chain n-3 polyunsaturated fatty acids and hence decreasing n-6:n-3 fatty acid ratio on inflammatory response in dextran sulfate sodium induced colitis. Male weanling Sprague Dawley rats were fed diets with n-6:n-3 fatty acid in the ratios of 215,50,10 or 5 for 3 months and colitis was induced by administration of dextran sulfate sodium in drinking water during last 11 days. Decreasing the dietary n-6:n-3 fatty acid ratio to 10 and 5 significantly attenuated the severity of colitis as evidenced by improvements in clinical symptoms, reversal of shortening of colon length, reduced severity of anemia, preservation of colonic architecture as well as reduced colonic mucosal myeloperoxidase activity. This protection was associated with suppression of colonic mucosal proinflammatory mediators such as TNFα, IL-1β and nitric oxide. These findings suggest that long chain n-3 polyunsaturated fatty acids at a level of 3.0 g/kg diet (n-6:n-3 ratio of 10) prevents dextran sulfate sodium induced colitis by suppressing the proinflammatory mediators. Topics: Animals; Colitis; Colon; Dextran Sulfate; Dietary Fats; Disease Models, Animal; Fatty Acids, Omega-3; Interleukin-1beta; Intestinal Mucosa; Linoleic Acid; Male; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha | 2014 |
Electroacupuncture ameliorates experimental colitis induced by TNBS through activation of interleukin-10 and inhibition of iNOS in mice.
To study the anti-inflammatory actions of electroacupuncture (EAc) on an experimental colitis model in mice.. Thirty-eight male Swiss mice, divided in five groups, were subjected to induction of colitis by TNBS in 50% ethanol. Saline (SAL) and ethanol (ETNL) groups served as controls. TNBS+EAc and TNBS+ dexamethasone subgroups were treated with EAc 100Hz and dexamethasone (DEXA) 1 mg/Kg/day, respectively. After three days, a colon segment was obtained for quantification of myeloperoxidase (MPO) activity, immunohistochemistry for iNOS, malondialdehyde (MDA) and cytokines (IL-1β and IL-10).. Neutrophilic activity, assayed as MPO activity, was significantly higher in the TNBS colitis group than that in the saline control group. TNBS+EAc group showed suppression of IL-10 in the colon. EAc treatment significantly reduced the concentration of MDA and the expression of iNOS, as compared to the other groups.. Electroacupuncture 100Hz applied to acupoint ST-36 promotes an anti-inflammatory action on the TNBS-induced colitis, mediated by increase of IL-10 and decrease of iNOS expression. Topics: Acupuncture Points; Animals; Anti-Inflammatory Agents; Colitis; Colon; Disease Models, Animal; Electroacupuncture; Immunohistochemistry; Inflammatory Bowel Diseases; Interleukin-10; Interleukin-1beta; Male; Malondialdehyde; Mice; Nitric Oxide Synthase Type II; Peroxidase; Random Allocation; Trinitrobenzenesulfonic Acid | 2014 |
Colonoscopy and µPET/CT are valid techniques to monitor inflammation in the adoptive transfer colitis model in mice.
Preclinical in vivo research on inflammatory bowel diseases requires proper animal models and techniques allowing longitudinal monitoring of colonic inflammation without the need to kill animals. We evaluated colonoscopy and μ-positron emission tomography/computed tomography (μPET/CT) as monitoring tools in a model for chronic colitis in mice.. Colitis was induced by adoptive transfer of CD4(+)CD25(-)CD62L(+) T cells in immunocompromised severe combined immunodeficient mice. Three study protocols were designed. In study 1, colonoscopy and µPET/CT were performed once, 4 weeks after transfer. In study 2 and study 3, colitis was sequentially followed up through colonoscopy (study 2) or colonoscopy plus µPET/CT (study 3). Each study included postmortem evaluation of colonic inflammation (macroscopy, microscopy, and myeloperoxidase activity).. In study 1, both colonoscopy and µPET/CT detected colitis 4 weeks after transfer. Study 2 showed a gradual increase in colonoscopic score from week 2 (1.4 ± 0.6) to week 8 (6.0 ± 1.1). In study 3, colitis was detected 2 weeks after transfer by µPET/CT (2.0 ± 0.4) but not by colonoscopy, whereas both techniques detected inflammation 4 and 6 weeks after transfer. Colonoscopy correlated with µPET/CT (r = 0.812, 0.884, and 0.781, respectively) and with postmortem analyses in all 3 studies.. Adoptive transfer of CD4(+)CD25(-)CD62L(+) T cells in severe combined immunodeficient mice results in a moderate chronic colitis. Evolution of colitis could be monitored over time by both colonoscopy and µPET/CT. µPET/CT seems to detect inflammation at an earlier time point than colonoscopy. Both techniques represent reliable and safe methods without the need to kill animals. Topics: Adoptive Transfer; Animals; CD4-Positive T-Lymphocytes; Colitis; Colonoscopy; Disease Models, Animal; Female; Inflammation; Mice; Mice, Inbred BALB C; Mice, SCID; Peroxidase; Positron-Emission Tomography; Tomography, X-Ray Computed | 2013 |
Beneficial effect of the non-psychotropic plant cannabinoid cannabigerol on experimental inflammatory bowel disease.
Inflammatory bowel disease (IBD) is an incurable disease which affects millions of people in industrialized countries. Anecdotal and scientific evidence suggests that Cannabis use may have a positive impact in IBD patients. Here, we investigated the effect of cannabigerol (CBG), a non-psychotropic Cannabis-derived cannabinoid, in a murine model of colitis. Colitis was induced in mice by intracolonic administration of dinitrobenzene sulphonic acid (DNBS). Inflammation was assessed by evaluating inflammatory markers/parameters (colon weight/colon length ratio and myeloperoxidase activity), by histological analysis and immunohistochemistry; interleukin-1β, interleukin-10 and interferon-γ levels by ELISA, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) by western blot and RT-PCR; CuZn-superoxide dismutase (SOD) activity by a colorimetric assay. Murine macrophages and intestinal epithelial cells were used to evaluate the effect of CBG on nitric oxide production and oxidative stress, respectively. CBG reduced colon weight/colon length ratio, myeloperoxidase activity, and iNOS expression, increased SOD activity and normalized interleukin-1β, interleukin-10 and interferon-γ changes associated to DNBS administration. In macrophages, CBG reduced nitric oxide production and iNOS protein (but not mRNA) expression. Rimonabant (a CB1 receptor antagonist) did not change the effect of CBG on nitric oxide production, while SR144528 (a CB2 receptor antagonist) further increased the inhibitory effect of CBG on nitric oxide production. In conclusion, CBG attenuated murine colitis, reduced nitric oxide production in macrophages (effect being modulated by the CB2 receptor) and reduced ROS formation in intestinal epithelial cells. CBG could be considered for clinical experimentation in IBD patients. Topics: Animals; Anti-Inflammatory Agents; Cannabinoids; Cell Line; Colitis; Colon; Cyclooxygenase 2; Epithelial Cells; Inflammatory Bowel Diseases; Interferon-gamma; Interleukin-10; Interleukin-1beta; Intestinal Mucosa; Ki-67 Antigen; Macrophages, Peritoneal; Male; Mice; Mice, Inbred ICR; Nitric Oxide Synthase Type II; Permeability; Peroxidase; Reactive Oxygen Species; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Superoxide Dismutase | 2013 |
Ameliorative effects of 3,4-oxo-isopropylidene-shikimic acid on experimental colitis and their mechanisms in rats.
The aim of the present study was to investigate the therapeutic effect and mechanism of 3,4-oxo-isopropylidene-shikimic acid (ISA) on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats. (50, 100, 200 mg/kg) was administered for 14 days, 1 day after the induction of colitis by TNBS. The colonic injury and inflammation were assessed by macroscopic damage scores and myeloperoxidase (MPO) activity. Malondialdehyde (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in plasma were measured with biochemical methods. Prostaglandin E2 (PGE2) level in colon was determined by radioimmunoassay. Expressions of inducible nitric oxide synthase (iNOS), cyclo-oxygenase-2 (COX-2), inhibitor kappa B-alpha (IκBα) and nuclear factor kappa B (NF-κB) p65 proteins in the colonic tissue were detected with immunohistochemistry. Enhanced colonic mucosal injury, inflammatory response and oxidative stress were observed in the animals clystered with TNBS, which was manifested as the significant increase in colon mucosal damage index, MPO activity, levels of MDA, NO and PGE2, as well as the expressions of iNOS, COX-2 and NF-κB p65 proteins in the colonic mucosa, and the significant decrease in expressions of IκBα proteins in the colonic mucosa. However, these parameters were found to be significantly ameliorated in rats treated with ISA at given doses, especially at 100 mg/kg and 200 mg/kg. Administration of ISA may have significant therapeutic effects on experimental colitis in rats, probably due to its mechanism of antioxidation, its inhibition of arachidonic acid metabolism and its modulation of the IκBα/NF-κB p65 expression. Topics: Animals; Antioxidants; Cells, Cultured; Colitis; Colon; Cyclooxygenase 2; Dinoprostone; Glutathione Peroxidase; Male; Malondialdehyde; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Sprague-Dawley; Shikimic Acid; Trinitrobenzenesulfonic Acid | 2013 |
Preventive and therapeutic oral administration of the pentacyclic triterpene α,β-amyrin ameliorates dextran sulfate sodium-induced colitis in mice: the relevance of cannabinoid system.
The pentacyclic triterpene α,β-amyrin has been previously reported as an effective compound in the treatment of several inflammatory conditions. Recent evidence indicates that α,β-amyrin displayed its effects through interaction with the cannabinoid pathway. We assessed the anti-inflammatory effects of the α,β-amyrin in the dextran sulfate sodium (DSS)-induced colitis in mice and investigated whether its effects were associated with the interaction with the cannabinoid system. Our results showed that the oral preventive or therapeutic treatment with α,β-amyrin significantly reduced disease activity, body weight loss, colonic damage, as well as colonic myeloperoxidase and N-acetylglucosaminidase activities. Moreover, α,β-amyrin decreases the colonic pro-inflammatory mediators tumor necrosis factor (TNF)-α, interleukin (IL)-1β and keratinocyte-derived chemokine (CXCL1/KC), while up-regulating the IL-4 levels. Additionally, we also observed that the α,β-amyrin caused a significant reduction of the adhesion molecules mRNA expression for intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), platelet cell adhesion molecule 1 (PCAM-1), β(2)-integrin and protein expression for proliferation marker Ki67, the macrophage molecule CD68 and for adhesion molecule P-selectin. Interestingly, our results also showed that the cannabinoid receptor 1 (CB(1)), but not CB(2), pharmacological blockade significantly reversed the beneficial effects of α,β-amyrin in DSS-induced colitis. Besides, our data demonstrated that mRNA expression for both the endocannabinoid hydrolase monoglyceride lipase 1 (MGL1) and fatty acid amide hydrolase (FAAH) were significantly reduced in the colon of α,β-amyrin-treated mice. Altogether, these results suggest that the α,β-amyrin might possess potential therapeutic interest for the treatment of IBD, and also provide new insights for the underlying mechanisms. Topics: Administration, Oral; Amidohydrolases; Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Asialoglycoproteins; Body Weight; Cannabinoids; CD18 Antigens; Cell Adhesion Molecules; Chemokines; Colitis; Colon; Dextran Sulfate; Intercellular Adhesion Molecule-1; Interleukin-1beta; Interleukin-4; Ki-67 Antigen; Lectins, C-Type; Male; Membrane Proteins; Mice; Oleanolic Acid; P-Selectin; Peroxidase; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; RNA, Messenger; Tumor Necrosis Factor-alpha; Up-Regulation; Vascular Cell Adhesion Molecule-1 | 2013 |
Nrf2 is not required for epithelial prohibitin-dependent attenuation of experimental colitis.
Inflammatory bowel disease is associated with increased reactive oxygen species (ROS) and decreased antioxidant response in the intestinal mucosa. Expression of the mitochondrial protein prohibitin (PHB) is also decreased during intestinal inflammation. Our previous study showed that genetic restoration of colonic epithelial PHB expression [villin-PHB transgenic (PHB Tg) mice] attenuated dextran sodium sulfate (DSS)-induced colitis/oxidative stress and sustained expression of colonic nuclear factor erythroid 2-related factor 2 (Nrf2), a cytoprotective transcription factor. This study investigated the role of Nrf2 in mediating PHB-induced protection against colitis and expression of the antioxidant response element (ARE)-regulated antioxidant genes heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase-1 (NQO-1). PHB-transfected Caco-2-BBE human intestinal epithelial cells maintained increased ARE activation and decreased intracellular ROS levels compared with control vector-transfected cells during Nrf2 knockdown by small interfering RNA. Treatment with the ERK inhibitor PD-98059 decreased PHB-induced ARE activation, suggesting that ERK constitutes a significant portion of PHB-mediated ARE activation in Caco-2-BBE cells. PHB Tg, Nrf2(-/-), and PHB Tg/Nrf2(-/-) mice were treated with DSS or 2,4,6-trinitrobenzene sulfonic acid (TNBS), and inflammation and expression of HO-1 and NQO-1 were assessed. PHB Tg/Nrf2(-/-) mice mimicked PHB Tg mice, with attenuated DSS- or TNBS-induced colitis and induction of colonic HO-1 and NQO-1 expression, despite deletion of Nrf2. PHB Tg/Nrf2(-/-) mice exhibited increased activation of ERK during colitis. Our results suggest that maintaining expression of intestinal epithelial cell PHB, which is decreased during colitis, reduces the severity of inflammation and increases colonic levels of the antioxidants HO-1 and NQO-1 via a mechanism independent of Nrf2. Topics: Animals; Antioxidant Response Elements; Blotting, Western; Caco-2 Cells; Cell Line; Colitis; Dextran Sulfate; Genes, Reporter; Heme Oxygenase-1; Humans; Luciferases; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Mice, Knockout; NAD(P)H Dehydrogenase (Quinone); NF-E2 Transcription Factor, p45 Subunit; Peroxidase; Prohibitins; Real-Time Polymerase Chain Reaction; Repressor Proteins; RNA; Tumor Necrosis Factor-alpha | 2013 |
A novel benzo[d]imidazole derivate prevents the development of dextran sulfate sodium-induced murine experimental colitis via inhibition of NLRP3 inflammasome.
NLRP3 inflammasome has been reported to be associated with various kinds of immunological diseases including colitis. However, there are few drug candidates targeting inflammasomes for the treatment of colitis. In the present study, we aimed at examining the effect of 1-ethyl-5-methyl-2-phenyl-1H-benzo[d]imidazole, a synthetic small molecular compound also named Fc11a-2, for the treatment of dextran sulfate sodium (DSS)-induced experimental colitis in mice via targeting NLRP3 inflammasome. Treatment with Fc11a-2 dose-dependently attenuated the loss of body weight and shortening of colon length induced by DSS. In addition, the disease activity index, histopathologic scores and myeloperoxidase activity were also significantly reduced by Fc11a-2 treatment. Moreover, protein and mRNA levels of DSS-induced proinflammatory cytokines in colon, including TNF-α, IL-1β, IL-18, IL-17A and IFN-γ, were markedly suppressed by Fc11a-2. Furthermore, a decreased CD11c⁺ macrophage infiltration in colons and inactivation of caspase-1 in peritoneal macrophages were detected in Fc11a-2-treated mice. The mechanism of action of Fc11a-2 was related to the inhibition of the cleavage of pro-caspase-1, pro-IL-1β and pro-IL-18 which in turn suppressed the activation of NLRP3 inflammasome. Taken together, our results demonstrate the ability of Fc11a-2 to inhibit NLRP3 inflammasome activation and its potential use in the treatment of inflammatory bowel diseases. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzimidazoles; Carrier Proteins; Caspase 1; Cell Line; Colitis; Colon; Cytokines; Dextran Sulfate; Dose-Response Relationship, Drug; Female; Gene Expression; Humans; Inflammasomes; Macrophages, Peritoneal; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; Neutrophils; NLR Family, Pyrin Domain-Containing 3 Protein; Peroxidase; Structure-Activity Relationship | 2013 |
Chrysin ameliorates chemically induced colitis in the mouse through modulation of a PXR/NF-κB signaling pathway.
Targeted activation of pregnane X receptor (PXR) in recent years has become a therapeutic strategy for inflammatory bowel disease. Chrysin is a naturally occurring flavonoid with anti-inflammation activity. The current study investigated the role of chrysin as a putative mouse PXR agonist in preventing experimental colitis. Pre-administration of chrysin ameliorated inflammatory symptoms in mouse models of colitis (dextran sodium sulfate- and 2,4,6-trinitrobenzene sulfonic acid-induced) and resulted in down-regulation of nuclear transcription factor κB (NF-κB) target genes (inducible NO synthase, intercellular adhesion molecule-1, monocyte chemotactic protein-1, cyclooxygenase 2, tumor necrosis factor-α, and interleukin 6) in the colon mucosa. Chrysin inhibited the phosphorylation/degradation of inhibitor κBα (IκBα), which correlated with the decrease in the activity of myeloperoxidase and the levels of tumor necrosis factor-α and interleukin 6 in the colon. Consistent with the in vivo results, chrysin blocked lipopolysaccharide -stimulated nuclear translocation of NF-κB p65 in mouse macrophage RAW264.7. Furthermore, chrysin dose-dependently activated human/mouse PXR in reporter gene assays and up-regulated xenobiotic detoxification genes in the colon mucosa, but not in the liver. Silencing of PXR by RNA interference demonstrated necessity of PXR in mediating chrysin's ability to induce xenobiotic detoxification genes and NF-κB inactivation. The repression of NF-κB transcription activity by chrysin was confirmed by in vitro PXR transduction. These findings suggest that the effect of chrysin in preventing chemically induced colitis is mediated in large part by a PXR/NF-κB pathway. The data also suggest that chrysin or chrysin-like flavonoids could be further developed as intestine-specific PXR activators. Topics: Animals; Blotting, Western; Colitis; Dextran Sulfate; Female; Flavonoids; Fluorescent Antibody Technique; Gene Silencing; Genes, Reporter; Humans; Interleukin-6; Mice; Mice, Inbred C57BL; NF-kappa B; Peroxidase; Pregnane X Receptor; Receptors, Steroid; RNA; Signal Transduction; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Up-Regulation | 2013 |
RNase-L deficiency exacerbates experimental colitis and colitis-associated cancer.
The endoribonuclease RNase-L is a type-I interferon (IFN)-regulated component of the innate immune response that functions in antiviral, antibacterial, and antiproliferative activities. RNase-L produces RNA agonists of RIG-I-like receptors, sensors of cytosolic pathogen-associated RNAs that induce cytokines including IFN-β. IFN-β and RIG-I-like receptors signaling mediate protective responses against experimental colitis and colitis-associated cancer and contribute to gastrointestinal homeostasis. Therefore, we investigated a role for RNase-L in murine colitis and colitis-associated cancer and its association with RIG-I-like receptors signaling in response to bacterial RNA.. Colitis was induced in wild type-deficient and RNase-L-deficient mice (RNase-L⁻/⁻) by administration of dextran sulfate sodium (DSS). Colitis-associated cancer was induced by DSS and azoxymethane (AOM). Histological analysis and immunohistochemistry were performed on colon tissue to analyze immune cell infiltration and tissue damage after induction of colitis. Expression of cytokines was measured by quantitative real-time-PCR and ELISA.. DSS-treated RNase-L⁻/⁻ mice exhibited a significantly higher clinical score, delayed leukocyte infiltration, reduced expression of IFN-β, tumor necrosis factor α, interleukin-1β, and interleukin-18 at early times post-DSS exposure, and increased mortality as compared with wild-type mice. DSS/AOM-treated RNase-L⁻/⁻ mice displayed an increased tumor burden. Bacterial RNA triggered IFN-β production in an RNase-L-dependent manner and provided a potential mechanism by which RNase-L contributes to the gastrointestinal immune response to microbiota and protects against experimental colitis and colitis-associated cancer.. RNase-L promotes the innate immune response to intestinal damage and ameliorates murine colitis and colitis-associated cancer. The RNase-L-dependent production of IFN-β stimulated by bacterial RNA may be a mechanism to protect against gastrointestinal inflammatory disease. Topics: Animals; Azoxymethane; Blotting, Western; Carcinogens; Colitis; Colonic Neoplasms; Cytokines; Dextran Sulfate; Disease Models, Animal; Endoribonucleases; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Immunity, Innate; Immunoenzyme Techniques; Interferon Type I; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Signal Transduction | 2013 |
The complement anaphylatoxin C3a receptor (C3aR) contributes to the inflammatory response in dextran sulfate sodium (DSS)-induced colitis in mice.
Inflammatory bowel diseases are a critical public health issue, and as treatment options remain limited, there is a need to unravel the underlying pathomechanisms in order to identify new therapeutic targets. Complement activation was found in patients suffering from inflammatory bowel disease, and the complement anaphylatoxin C5a and its receptor C5aR have been implicated in disease pathogenesis in animal models of bowel inflammation. To further characterize complement-related pathomechanisms in inflammatory bowel disease, we have investigated the role of the anaphylatoxin C3a receptor in acute dextran sulfate sodium-induced colitis in mice. For this, colitis was induced in C3a receptor-deficient BALB/c and C57BL/6 mice, and disease severity was evaluated by clinical and histological examination, and by measuring the mRNA expression or protein levels of inflammatory mediators in the tissue. C3a receptor deficiency was partially protective in BALB/c mice, which had significantly reduced weight loss, clinical and histological scores, colon shortening, and CXCL-1/KC mRNA, myeloperoxidase and interleukin-6 tissue levels compared to the corresponding wild type mice. In C57BL/6 mice the differences between wild type and C3a receptor-deficient animals were much smaller and reached no significance. Our data demonstrate that the contribution of C3a receptor to disease pathogenesis and severity of dextran sulfate sodium-induced colitis in mice depends on the genetic background. Further studies will be required to clarify whether targeting of C3a receptor, possibly in combination with C5a receptor, might be considered as a therapeutic strategy for inflammatory bowel disease. Topics: Acute Disease; Animals; Colitis; Colon; Complement Activation; Complement C3a; Cytokines; Dextran Sulfate; Gene Expression Regulation; Inflammation; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Peroxidase; Receptors, Complement; RNA, Messenger | 2013 |
Budesonide-loaded nanostructured lipid carriers reduce inflammation in murine DSS-induced colitis.
The challenge for the treatment of inflammatory bowel disease (IBD) is the delivery of the drug to the site of inflammation. Because nanoparticles have the ability to accumulate in inflamed regions, the aim of the present study was to evaluate nanostructured lipid carriers (NLCs) as nanoparticulate drug delivery systems for the treatment of IBD. Budesonide (BDS) was chosen as a candidate anti-inflammatory drug. BDS-loaded NLCs (BDS-NLC) produced by high-pressure homogenization had a size of 200 nm and a negative zeta potential. BDS-NLCs reduced the TNF-α secretion by activated macrophages (J774 cells). BDS-NLCs were more active in a murine model of dextran sulfate-induced colitis when compared with Blank-NLCs or a BDS suspension: BDS-NLCs decreased neutrophil infiltration, decreased the levels of the pro-inflammatory cytokines IL-1β and TNF-α in the colon and improved the histological scores of the colons. These data suggest that NLCs could be a promising alternative to polymeric nanoparticles as a targeted drug delivery system for IBD treatment. Topics: Animals; Anti-Inflammatory Agents; Budesonide; Cell Line; Colitis; Colon; Dextran Sulfate; Drug Carriers; Female; Inflammation; Interleukin-1beta; Lipids; Mice; Mice, Inbred C57BL; Nanostructures; Peroxidase; Tumor Necrosis Factor-alpha | 2013 |
Gastrointestinal pain: unraveling a novel endogenous pathway through uroguanylin/guanylate cyclase-C/cGMP activation.
The natural hormone uroguanylin regulates intestinal fluid homeostasis and bowel function through activation of guanylate cyclase-C (GC-C), resulting in increased intracellular cyclic guanosine-3',5'-monophosphate (cGMP). We report the effects of uroguanylin-mediated activation of the GC-C/cGMP pathway in vitro on extracellular cGMP transport and in vivo in rat models of inflammation- and stress-induced visceral hypersensitivity. In vitro exposure of intestinal Caco-2 cells to uroguanylin stimulated bidirectional, active extracellular transport of cGMP into luminal and basolateral spaces. cGMP transport was significantly and concentration dependently decreased by probenecid, an inhibitor of cGMP efflux pumps. In ex vivo Ussing chamber assays, uroguanylin stimulated cGMP secretion from the basolateral side of rat colonic epithelium into the submucosal space. In a rat model of trinitrobenzene sulfonic acid (TNBS)-induced visceral hypersensitivity, orally administered uroguanylin increased colonic thresholds required to elicit abdominal contractions in response to colorectal distension (CRD). Oral administration of cGMP mimicked the antihyperalgesic effects of uroguanylin, significantly decreasing TNBS- and restraint stress-induced visceromotor response to graded CRD in rats. The antihyperalgesic effects of cGMP were not associated with increased colonic spasmolytic activity, but were linked to significantly decreased firing rates of TNBS-sensitized colonic afferents in rats in response to mechanical stimuli. In conclusion, these data suggest that the continuous activation of the GC-C/cGMP pathway along the intestinal tract by the endogenous hormones guanylin and uroguanylin results in significant reduction of gastrointestinal pain. Extracellular cGMP produced on activation of GC-C is the primary mediator in this process via modulation of sensory afferent activity. Topics: Acetylcholine; Acetylglucosamine; Adenocarcinoma; Animals; Cell Differentiation; Cell Line, Tumor; Colitis; Colon; Colorectal Neoplasms; Cyclic GMP; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Interactions; Electric Stimulation; Female; Gastrointestinal Diseases; Gene Expression Regulation, Neoplastic; Guanylate Cyclase; Humans; Hyperalgesia; Intestinal Mucosa; Male; Mast Cells; Morphine; Multidrug Resistance-Associated Proteins; Natriuretic Peptides; Organic Anion Transporters, Sodium-Independent; Peroxidase; Rats; Rats, Sprague-Dawley; Rats, Wistar; Restraint, Physical; RNA, Messenger; Signal Transduction; Trinitrobenzenesulfonic Acid; Visceral Pain | 2013 |
PepT1 expressed in immune cells has an important role in promoting the immune response during experimentally induced colitis.
We and others have shown that the dipeptide cotransporter PepT1 is expressed in immune cells, including macrophages that are in close contact with the lamina propria of the small and large intestines. In the present study, we used PepT1-knockout (KO) mice to explore the role played by PepT1 in immune cells during dextran sodium sulfate (DSS)-induced colitis. DSS treatment caused less severe body weight loss, diminished rectal bleeding, and less diarrhea in PepT1-KO mice than in wild-type (WT) animals. A histological examination of colonic sections revealed that the colonic architecture was less disrupted and the extent of immune cell infiltration into the mucosa and submucosa following DSS treatment was reduced in PepT1-KO mice compared with WT animals. Consistent with these results, the DSS-induced colitis increase in colonic myeloperoxidase activity was significantly less in PepT1-KO mice than in WT littermates. The colonic levels of mRNAs encoding the inflammatory cytokines CXCL1, interleukin (IL)-6, monocyte chemotactic protein-1, IL-12, and interferon-γ were significantly lower in DSS-treated PepT1-KO mice than in DSS-treated WT animals. Colonic immune cells from WT had significantly higher level of proinflammatory cytokines then PepT1 KO. In addition, we observed that knocking down the PepT1 expression decreases chemotaxis of immune cells recruited during intestinal inflammation. Antibiotic treatment before DSS-induced colitis eliminated the differential expression of inflammatory cytokines between WT and PepT1-KO mice. In conclusion, PepT1 in immune cells regulates the secretion of proinflammatory cytokines triggered by bacteria and/or bacterial products, and thus has an important role in the induction of colitis. PepT1 may transport small bacterial products, such as muramyl dipeptide and the tripeptide L-Ala-gamma-D-Glu-meso-DAP, into macrophages. These materials may be sensed by members of the nucleotide-binding site-leucine-rich repeat family of intracellular receptors, ultimately resulting in altered homeostasis of the intestinal microbiota. Topics: Animals; Anti-Bacterial Agents; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Female; Gene Expression; Gene Knockdown Techniques; Homeostasis; Immunity, Cellular; Macrophages; Mice; Mice, Inbred C57BL; Mice, Knockout; Peptide Transporter 1; Peroxidase; RNA, Messenger; Symporters | 2013 |
The role of cholinergic anti-inflammatory pathway in acetic acid-induced colonic inflammation in the rat.
The "cholinergic anti-inflammatory pathway" provides neurological modulation of cytokine synthesis to limit the magnitude of the immune response. This study aimed to evaluate the impact of the cholinergic anti-inflammatory pathway on the extent of tissue integrity, oxidant-antioxidant status and neutrophil infiltration to the inflamed organ in a rat model of acetic acid-induced colitis. Colitis was induced by intrarectal administration of 5% acetic acid (1ml) to Sprague-Dawley rats (200-250g; n=7-8 per group). Control group received an equal volume of saline intrarectally. The rats were treated with either nicotine (1mg/kg/day) or huperzine A (0.1mg/kg/day) intraperitoneally for 3 days. After decapitation, the distal colon was scored macroscopically and microscopically. Tissue samples were used for the measurement of malondialdehyde (MDA) and glutathione (GSH) levels, and myeloperoxidase (MPO) activity. Formation of reactive oxygen species was monitored by using chemiluminescence (CL). Nuclear factor (NF)-κB expression was evaluated in colonic samples via immunohistochemical analysis. Trunk blood was collected for the assessment of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-10, resistin and visfatin levels. Both nicotine and huperzine A reduced the extent of colonic lesions, increased colonic MDA level, high MPO activity and NF-κB expression in the colitis group. Elevation of serum IL-1β level due to colitis was also attenuated by both treatments. Additionally, huperzine A was effective to reverse colitis-induced high lucigenin-enhanced CL values and serum TNF-α levels. Colitis group revealed decreased serum visfatin levels compared to control group which was completely reversed by nicotine. In conclusion, modulation of the cholinergic system either by nicotine or ACh esterase inhibition improved acetic acid-induced colonic inflammation as confirmed by macroscopic and microscopic examination and biochemical assays. Topics: Acetic Acid; Alkaloids; Animals; Antioxidants; Cholinergic Neurons; Cholinesterase Inhibitors; Colitis; Colon; Cytokines; Female; Glutathione; Male; Malondialdehyde; Neuroimmunomodulation; NF-kappa B; Nicotinamide Phosphoribosyltransferase; Nicotine; Nicotinic Agonists; Peroxidase; Rats; Rats, Sprague-Dawley; Resistin; Sesquiterpenes | 2013 |
Curcumin ameliorates dextran sulfate sodium-induced experimental colitis by blocking STAT3 signaling pathway.
Although a series of studies have shown that curcumin can exert anti-inflammatory effects in colitis by inhibiting NF-κB activation, whether these anti-inflammatory effects of curcumin are also attributed to its ability to inhibiting STAT3 pathway has never been tested in experimental colitis to date. The purpose of the study was to investigate whether curcumin could exert its therapeutic effects in experimental colitis by inhibiting STAT3 pathway.. Curcumin was administered in experimental colitis induced by dextran sulfate sodium (DSS). The disease activity index (DAI) and histological score were observed. The phospho-STAT3 was assessed by western blot analysis. The DNA-binding activity of STAT3 dimers was evaluated by electrophoretic mobility shift assay (EMSA). The expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1β was measured by enzyme-linked immunosorbent assay. Myeloperoxidase (MPO) activity was determined by using MPO assay kit.. A significant improvement was observed in DAI and histological score in mice with curcumin, and the increases in phospho-STAT3 activity, DNA-binding activity of STAT3 dimers, MPO activity, IL-1β, and TNF-α expression in mice with DSS-induced colitis were significantly reduced following treatment with curcumin.. Curcumin exerts beneficial effects in experimental colitis by the suppression of STAT3 pathway, which may therefore provide a better understanding of the mechanism of action for curcumin in treating colitis. Topics: Animals; Colitis; Colon; Curcumin; Dextran Sulfate; Down-Regulation; Interleukin-1beta; Male; Mice; Mice, Inbred BALB C; Peroxidase; Phosphorylation; Signal Transduction; STAT3 Transcription Factor; Tumor Necrosis Factor-alpha | 2013 |
Effects of retinoids in mouse models of colitis: benefit or danger to the gastrointestinal tract?
In vitro and in vivo data have shown that retinoid treatment promotes an anti-inflammatory milieu with few adverse effects toward the gastrointestinal tract. The in vivo studies reported here further evaluate retinoid effects in 2 mouse models of inflammatory bowel disease.. Chronic dextran sulfate sodium colitis was induced in age- and weight-matched C57Bl/6 mice by 4 cycles of dextran sulfate sodium administration (6-8 animals/group). At cycle 4, animals were administered 13-cis-retinoic acid (isotretinoin, 30 mg/kg) or vehicle (oral gavage) or 4-oxo-13-cis-retinoic acid (15 mg/kg, intraperitoneal) daily. T-cell transfer colitis was induced in CB17 SCID mice by transfer of naive CD4CD62L T cells and treated by transfer of regulatory CD4CD25 T cells (4-6 animals/group); isolated from BALB/c mice after treatment with isotretinoin or vehicle, as above, for 2 weeks. Assessments included endoscopic and histological scores, myeloperoxidase activity, serum cytokines, and plasma isotretinoin levels.. Retinoid-treated animals with colitis showed comparable changes in myeloperoxidase activity, and endoscopic and histological scores, versus untreated animals with colitis. Modest and comparable changes were seen in body weight and colon length in animals injected with naive T cells from isotretinoin-treated donors versus those injected with T cells from vehicle-treated donors. Retinoid treatment was consistently associated with lower interleukin-12 levels, which, after the transfer of naive T cells from isotretinoin-treated donors, supported isotretinoin-mediated predisposition of naive T cells toward reduced proinflammatory cytokine expression. Colitis had no effect on isotretinoin exposure.. Retinoids attenuate the proinflammatory cytokine response in vivo, with only modest effects on body weight and parameters of gastrointestinal morphology. Topics: Animals; CD4-Positive T-Lymphocytes; Colitis; Cytokines; Dermatologic Agents; Dextran Sulfate; Disease Models, Animal; Female; Flow Cytometry; Gastrointestinal Tract; Isotretinoin; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, SCID; Peroxidase; T-Lymphocytes, Regulatory | 2013 |
Involvement of MAPK/NF-κB signaling in the activation of the cholinergic anti-inflammatory pathway in experimental colitis by chronic vagus nerve stimulation.
Autonomic nervous system dysfunction is implicated in the etiopathogenesis of inflammatory bowel diseases (IBD). Therapies that increase cardiovagal activity, such as Mind-Body interventions, are currently confirmed to be effective in clinical trials in IBD. However, a poor understanding of pathophysiological mechanisms limits the popularization of therapies in clinical practice. The aim of the present study was to explore the mechanisms of these therapies against 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats using a chronic vagus nerve stimulation model in vivo, as well as the lipopolysaccharide (LPS)-induced inflammatory response in human epithelial colorectal adenocarcinoma cells (Caco-2) by acetylcholine in vitro.. Colitis was induced in rats with rectal instillation of TNBS, and the effect of chronic VNS (0.25 mA, 20 Hz, 500 ms) on colonic inflammation was evaluated. Inflammatory responses were assessed by disease activity index (DAI), histological scores, myeloperoxidase (MPO) activity, inducible nitric oxide synthase (iNOS), TNF-α and IL-6 production. The expression of Mitogen-activated protein kinases (MAPK) family members, IκB-α, and nuclear NF-κB p65 were studied by immunoblotting. Heart rate variability (HRV) analysis was also applied to assess the sympathetic-vagal balance. DAI, histological scores, MPO activity, iNOS, TNF-α and IL-6 levels were significantly decreased by chronic VNS. Moreover, both VNS and acetylcholine reduced the phosphorylation of MAPKs and prevented the nuclear translocation of NF-κB p65. Methyllycaconitine (MLA) only reversed the inhibitory effect on p-ERK and intranuclear NF-κB p65 expression by ACh in vitro, no significant change was observed in the expression of p-p38 MAPK or p-JNK by MLA.. Vagal activity modification contributes to the beneficial effects of the cholinergic anti-inflammatory pathway in IBD-related inflamed colonic mucosa based on the activation of MAPKs and nuclear translocation of NF-κB. Our work may provide key pathophysiological mechanistic evidence for novel therapeutic strategies that increase the cardiovagal activity in IBD patients. Topics: Acetylcholine; Animals; Anti-Inflammatory Agents; Caco-2 Cells; Colitis; Female; Humans; Immunoblotting; Immunoenzyme Techniques; Inflammation; Interleukin-6; Lipopolysaccharides; Male; Mitogen-Activated Protein Kinases; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Phosphorylation; Rats; Rats, Sprague-Dawley; Signal Transduction; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Vagus Nerve Stimulation | 2013 |
Effect of sodium alginate on dextran sulfate sodium- and 2,4,6-trinitrobenzene sulfonic acid-induced experimental colitis in mice.
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. Topics: Alginates; Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Glucuronic Acid; Hexuronic Acids; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Peroxidase; Protective Agents; Serum Amyloid A Protein; Trinitrobenzenes | 2013 |
A study comparing the efficacy of antimicrobial agents versus enzyme (P-gp) inducers in the treatment of 2,4,6 trinitrobenzenesulfonic acid-induced colitis in rats.
The intestinal microflora is an important cofactor in the pathogenesis of intestinal inflammation; and the epithelial cell barrier function is critical in providing protection against the stimulation of mucosal immune system by the microflora. In the present study, therapeutic role of the antibacterial drugs rifampicin and ciprofloxacine were investigated in comparison to spironolactone, an enzyme inducer, in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis of the rats. Drugs were administered for 14 days following induction of colitis. All drug treatments ameliorated the clinical hallmarks of colitis as determined by body weight loss and assessment of diarrhea, colon length, and histology. Oxidative damage and neutrophil infiltration as well as nuclear factor κB (NF-κB) and tumor necrosis factor α (TNF-α) expressions that were increased during colitis, were decreased significantly. Rifampicin and ciprofloxacin were probably effective due to their antibacterial and immunomodulating properties. The multidrug resistence gene (MDR1) and its product p-glycoprotein (P-gp) has been implicated in the pathogenesis of inflammatory bowel disease (IBD). In the present study, findings of the P-gp expression were inconclusive but regarding previous studies, it can be suggested that the beneficial effects of rifampicin and spironolactone may be partly due to their action as a P-gp ligand. Spironolactone has been reported to supress the transcription of proinflamatory cytokines that are considered to be of importance in immunoinflammatory diseases. It is also a powerful pregnane X receptor (PXR) inducer; thus, inhibition of the expression of NF-κB and TNF-α, and amelioration of inflammation by spironolactone suggest that this may have been through the activation of PXR. However, our findings regarding PXR expression were inconclusive. Activation of PXR by spironolactone probably also contributed to the induction of P-gp, resulting in extrusion of noxious substances from the tissue. Topics: Animals; Anti-Bacterial Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Ciprofloxacin; Colitis; Colon; Glutathione; Ileum; Male; Malondialdehyde; NF-kappa B; Peroxidase; Pregnane X Receptor; Rats; Rats, Sprague-Dawley; Receptors, Steroid; Rifampin; Spironolactone; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2013 |
Gut microbiota affects sensitivity to acute DSS-induced colitis independently of host genotype.
Caspase-deficient mice and wild-type (WT) mice show significant differences in their gut microbiota composition. These differences coincide with the observation that caspase-3-deficient mice carrying a natural caspase-11 mutation (Casp3/11(-/-)) are less sensitive to acute dextran sodium sulfate-induced colitis than WT mice. For these reasons, we investigated the role of the microbiota in the development of colitis by cohousing WT and Casp3/11(-/-) mice. Microbial community fingerprinting by denaturing gradient gel electrophoresis analysis revealed that the similarities in gut microbial composition of WT and Casp3/11(-/-) mice increased after cohousing. In the acute dextran sodium sulfate-induced colitis model, Casp3/11(-/-) mice that were cohoused with WT mice showed increased weight loss and disease activity scores and increased neutrophil infiltration and inflammatory cytokine levels in their colon tissue compared with Casp3/11(-/-) mice that were not cohoused with WT mice. Also, we demonstrate that only the microbiota of the Casp3/11(-/-) mice cohoused with WT mice showed an important increase in Prevotella species. In conclusion, our cohousing experiments revealed that the colitogenic activity of the WT microbiota is transferable to Casp3/11(-/-) mice and that Prevotella species are likely to be involved. By contrast, the relative protection of Casp3/11(-/-) mice against dextran sodium sulfate damage is not transferred to WT mice after cohousing. These results underscore the need for in-depth studies of the bilateral interaction of host genes and microbiota to gain insight into the mechanisms of disease pathogenesis. Our findings also have important implications for the experimental design of disease studies in genetically modified mice and conclusions drawn from them. Topics: Acute Disease; Animals; Caspase 3; Cell Proliferation; Colitis; Cytokines; Dextran Sulfate; Feces; Female; Flow Cytometry; Gastrointestinal Tract; Host-Pathogen Interactions; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Microbiota; Peroxidase; Real-Time Polymerase Chain Reaction | 2013 |
Intestinal anti-inflammatory activity of ellagic acid in the acute and chronic dextrane sulfate sodium models of mice colitis.
Pomegranate (Punica granatum L.; Lythraceae) has traditionally been used for the treatment of various inflammatory diseases, including ulcerative colitis (UC). Because its fruits and extracts are rich in ellagitannins, which release ellagic acid when hydrolyzed, consumption of pomegranate products is currently being widely promoted for their potential health effects, including the prevention of inflammatory diseases and cancer. To evaluate the anti-inflammatory effects of ellagic acid on dextran sulfate sodium (DSS)-induced acute and chronic experimental colitis in two different strains of mice and to elucidate its possible mechanisms of action.. In the acute UC model, female Balb/C mice were treated with DSS (5%) for seven days while concomitantly receiving a dietary supplement of ellagic acid (2%). In the chronic UC model, female C57BL/6 mice received four week-long cycles of DSS (1% and 2%) interspersed with week-long recovery periods along with a diet supplemented with ellagic acid (0.5%).. In acute model of UC, ellagic acid ameliorated disease severity slightly as observed both macroscopically and through the profile of inflammatory mediators (IL-6, TNF-α, and IFN-γ). In the chronic UC model, ellagic acid significantly inhibited the progression of the disease, reducing intestinal inflammation and decreasing histological scores. Moreover, mediators such as COX-2 and iNOS were downregulated and the signaling pathways p38 MAPK, NF-κB, and STAT3 were blocked.. Our study reinforces the hypothetical use of ellagic acid as an anti-inflammatory complement to conventional UC treatment in chronic UC patients and could be considered in the dietary prevention of intestinal inflammation and related cancer development. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Ellagic Acid; Female; I-kappa B Proteins; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; NF-kappa B; NF-KappaB Inhibitor alpha; p38 Mitogen-Activated Protein Kinases; Peroxidase; STAT3 Transcription Factor | 2013 |
Antidiarrheal and intestinal antiinflammatory activities of a methanolic extract of Qualea parviflora Mart. in experimental models.
An ethnopharmacological survey indicated that the bark from Qualea parviflora Mart. (Vochysiaceae) could be used to treat gastrointestinal disorders, such as diarrhea and intestinal inflammation. The objective of this study was to evaluate the effects of a methanolic extract from the bark of Qualea parviflora (QP) in an experimental model of diarrhea and intestinal inflammation induced in rodents.. The antidiarrheal and antispasmodic effects of QP were investigated by measuring intestinal motility, diarrhea, and intestinal fluid accumulation in rodents after challenging with a cathartic agent. In addition, the effects of QP on the contractility of the isolated mice-ileum preparation were determined. Acute intestinal inflammation was induced in male Wistar rats by the rectal administration of trinitrobenzenesulfonic acid (TNBS) in 50% ethanol (0.25 mL). QP was administered orally (for 5 days) prior to the induction of inflammation. The colonic injury and extent of inflammation were assessed by macroscopic damage scores and lesion length. The enhanced colonic mucosal injury, inflammatory response, and oxidative stress were evaluated by myeloperoxidase (MPO) activity; the tumor necrosis factor alpha (TNF-α), interleukin 1β (IL1-β), and malondialdehyde (MDA) levels; and the glutathione (GSH) content.. Oral treatment with QP (500 mg/kg) delayed the onset of diarrhea, reduced the amount of liquid stool, and decreased the severity of the diarrhea and the evacuation index in rodents challenged with castor oil (p<0.01). Additionally, QP (150-500 µg/mL) demonstrated effective antispasmodic activity against carbachol-induced contractions of mouse ileum in vitro. Oral treatment (25 and 50 mg/kg/day) with QP significantly reduced the intestinal inflammation induced by TNBS in rats (52% and 45%, respectively). Improvement of colonic mucosal injury by treatment with QP was demonstrated by a decrease in MDA levels and an increase in GSH content in colonic tissue. QP also prevented intestinal inflammation as evidenced by reduced cytokine levels (TNF-α and IL1-β) and low MPO activity.. The ethnopharmacological usefulness of the bark from Qualea parviflora against diarrhea containing blood and mucus was supported by the observed antidiarrheal, antispasmodic, and intestinal antiinflammatory properties of this medicinal plant. Topics: Animals; Anti-Inflammatory Agents; Antidiarrheals; Castor Oil; Colitis; Colon; Diarrhea; Gastrointestinal Motility; Glutathione; Ileum; Interleukin-1beta; Male; Malondialdehyde; Methanol; Mice; Muscle Contraction; Parasympatholytics; Peroxidase; Phytotherapy; Plant Bark; Plant Extracts; Rats; Rats, Wistar; Solvents; Tracheophyta; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2013 |
Beneficial effects of an amino acid mixture on colonic mucosal healing in rats.
Mucosal healing (MH) decreases the relapse risk in patients with inflammatory bowel disease, but the role of dietary supplementation in this process has been poorly investigated. Here, we investigated the effect of an amino acid mixture supplement on rat MH.. Colitis was induced using 5% of dextran sodium sulfate for 6 days. Then, rats received a mixture of threonine (0.50 g/d), methionine (0.31 g/d), and monosodium glutamate (0.57 g/d) or an isonitrogenous amount of alanine (control group). Colons were recovered after colitis induction and after dietary supplementation for measuring colon characteristics, myeloperoxidase, cytokine gene expression, glutathione content, protein synthesis rate, and for histological analysis. Short-chain fatty acids were measured in the colonic content.. Colitis induction resulted in anorexia, thickening and shortening of the colon, and ulceration. Colonic cytokine expression and neutrophil infiltration were increased. An increased amount of water and a decreased amount of butyrate, propionate, and acetate were measured in the colonic content. Supplementation with the amino acid mixture coincided with a reduced protein synthesis rate in the colon compatible with the observed increased colonic MH. Mucosal regeneration/re-epithelialization was visible within 3 days after colitis induction at a time when mucosal inflammation was severe. Histological analysis revealed an increased regeneration/re-epithelialization after 10-day supplementation. In contrast, the spontaneous resolution of inflammation was not affected by the supplementation.. Amino acid supplementation ameliorates colonic MH but not mucosal inflammatory status. Our data sustain the use of adjuvant dietary intervention on initiated intestinal MH. Topics: Amino Acids; Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Glutathione; Immunoenzyme Techniques; Intestinal Mucosa; Male; Peroxidase; Rats; Rats, Wistar | 2013 |
Inhibitory effect of the gallotannin corilagin on dextran sulfate sodium-induced murine ulcerative colitis.
The therapeutic effect of corilagin (1) was evaluated in an acute colitis model induced by dextran sulfate sodium (DSS) in mice, and the mechanism of action was investigated in this study. Animals were challenged with 2% DSS drinking water for 5 consecutive days and then intraperitoneally treated with 1 (7.5, 15, and 30 mg/kg) daily for 7 days. It was found that 1 significantly decreased the disease activity index, inhibited the shortening of colon length, reduced colon tissue damage, and suppressed myeloperoxidase activity. Moreover, 1 greatly suppressed the secretion of TNF-α, IL-6, and IL-1β, inhibited the degradation of IκB α, and down-regulated expression of cleaved caspase-3 and cleaved caspase-9 in colon tissues of DSS-treated mice. These findings demonstrated that 1 exerts a protective effect on DSS-induced colitis, and its underlying mechanisms are associated with inhibition of the NF-κB pathway that mitigates colon inflammatory responses and apoptosis of intestinal epithelial cells. Topics: Animals; Apoptosis; Caspase 3; Caspase 9; Colitis; Colitis, Ulcerative; Colon; Dextran Sulfate; Drinking Water; Epithelial Cells; Glucosides; Hydrolyzable Tannins; Interleukin-16; Interleukin-1beta; Male; Mice; Mice, Inbred C57BL; Molecular Structure; NF-kappa B; Peroxidase; Signal Transduction; Tumor Necrosis Factor-alpha | 2013 |
Exacerbation of DSS-induced colitis in mice lacking kinin B(1) receptors through compensatory up-regulation of kinin B(2) receptors: the role of tight junctions and intestinal homeostasis.
Kinins are pro-inflammatory peptides that are released during tissue injury, including that caused by inflammatory bowel disease. Herein, we assessed the role and underlying mechanisms through which the absence of kinin B(1) receptors exacerbates the development of dextran sulfate sodium (DSS)-induced colitis in mice.. B(1) and B(2) receptor antagonists and B(1) receptor knockout mice (B1(-/-) ) were used to assess the involvement of B(1) and B(2) receptor signalling in a DSS-colitis. B(1) receptor, B(2) receptor, occludin and claudin-4 expression, cytokine levels and cell permeability were evaluated in colon from wild-type (WT) and B1(-/-) mice.. DSS-induced colitis was significantly exacerbated in B1(-/-) compared with WT mice. IL-1β, IFN-γ, keratinocyte-derived chemokine and macrophage inflammatory protein-2 were markedly increased in the colon from DSS-treated B1(-/-) compared with DSS-treated WT mice. Treatment of WT mice with a selective B(1) receptor antagonist, DALBK or SSR240612, had no effect on DSS-induced colitis. Of note, B(2) receptor mRNA expression was significantly up-regulated in colonic tissue from the B1(-/-) mice after DSS administration. Moreover, treatment with a selective B(2) receptor antagonist prevented the exacerbation of colitis in B1(-/-) mice following DSS administration. The water- or DSS-treated B1(-/-) mice showed a decrease in occludin gene expression, which was partially prevented by the B(2) receptor antagonist.. A loss of B(1) receptors markedly exacerbates the severity of DSS-induced colitis in mice. The increased susceptibility of B1(-/-) may be associated with compensatory overexpression of B(2) receptors, which, in turn, modulates tight junction expression. Topics: Animals; Bradykinin; Bradykinin B1 Receptor Antagonists; Bradykinin B2 Receptor Antagonists; Colitis; Cytokines; Dextran Sulfate; Dioxoles; Homeostasis; Intestinal Mucosa; Intestines; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Receptor, Bradykinin B1; Receptor, Bradykinin B2; Sulfonamides; Tight Junctions; Up-Regulation | 2013 |
Establishment and validation of a new semi-chronic dextran sulfate sodium-induced model of colitis in mice.
The dextran sulfate sodium (DSS)-induced model of colitis is a commonly used model of inflammatory bowel disease (IBD) in animals. However, there were few studies on the therapeutic efficacy of drugs for IBD after the onset of colitis in this model. We established a semi-chronic model of DSS-induced colitis in mice and used it to assess the therapeutic efficacy of agents for IBD.. Colitis was induced by administration of 3% DSS in drinking water to mice for 7days followed by 5days of normal drinking water.. Ulcerative colitis (UC)-like symptoms including diarrhea, bloody stools and body-weight loss were observed from days 3 to 5, and continued until day 12 after DSS administration. Persistent colitis was associated with sustained local production of cytokines and was characterized by infiltration of inflammatory cells, crypt loss and erosion in the distal colon. These features are similar to those found in patients with UC. In this model, anti-tumor necrosis factor (TNF)-α antibody or anti-interleukin (IL)-12/23p40 antibody significantly ameliorated colitis when administered after the onset of colitis. However, treatment with FK506, prednisolone or sulfasalazine provided limited therapeutic benefit.. The DSS-induced colitis established here showed similar symptomatic and histopathological features to those seen in human UC. This model may be available for predicting the clinical efficacy of candidate compounds for UC. Topics: Animals; Anti-Inflammatory Agents; Antibodies; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Female; Gastrointestinal Agents; Immunosuppressive Agents; Inflammatory Bowel Diseases; Mice; Mice, Inbred C57BL; Peroxidase; Prednisolone; Sulfasalazine; Tacrolimus | 2013 |
The possible mechanisms of Picrasma quassiodes (D. Don) Benn. in the treatment of colitis induced by 2,4,6-trinitrobenzene sulfonic acid in mice.
Picrasma quassiodes (D. Don) Benn.(PQB) is used in folk medicines for the treatment of colds, upper respiratory infection, acute tonsillitis, acute gastroenteritis, bacillary dysentery and a variety of acute infectious diseases in Asia. Although recent reports indicate that PQB has antibacterial, and anti-inflammatory effects, its effects on colitis and its inhibitory mechanisms have not been previously reported.. To assess the effects and the mode of action of the extract of Picrasma quassiodes (D. Don) Benn.(PQB) on a model of colitis in mice induced by trinitrobenzene sulfonic acid (TNBS).. We induced mice colitis using TNBS/ethanol, then different doses of Picrasma quassiodes (D. Don) Benn.(PQB) extract (100, 200 and 400 mg/kg/day) and sulfasalazine (500 mg/kg/day) were administered by gavage for 7 days after the induction of colitis. The mice body weight, colonic wet weight, colonic lengths, myeloperoxidase (MPO) activity, macroscopic and histological colon injury were observed. Pro-inflammatory cytokines such as: tumor necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8) were assayed by enzyme-linked immunoassay. The protein expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in the colons were determined by immunohistochemical analysis.. PQB administration effectively prevented mice diarrhea, decreasing of the body weights, shortening of colon length and increasing of colon wet weight. Macroscopic and histological examinations also indicated that it was protected against colonic edema, ulceration and MPO activity elevation. Furthermore, PQB inhibited the abnormal secretions of pro-inflammatory cytokines, such as TNF-α and IL-8. Additionally, administration of PQB effectively inhibited COX-2 and iNOS protein expression.. These results suggest that PQB has an anti-inflammatory effect on TNBS-induced colitis due to the down-regulations of the productions and expressions of inflammatory mediators, and that it may be a potential inflammatory bowel disease (IBD) drug candidate. Topics: Animals; Anti-Inflammatory Agents; Colitis; Cyclooxygenase 2; Interleukin-8; Male; Mice; Mice, Inbred BALB C; Nitric Oxide Synthase Type II; Peroxidase; Phytotherapy; Picrasma; Plant Extracts; Plant Stems; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2013 |
Curcumin improves TNBS-induced colitis in rats by inhibiting IL-27 expression via the TLR4/NF-κB signaling pathway.
Curcumin is a widely used spice with anti-inflammatory and anticancer properties. It has been reported to have beneficial effects in experimental colitis. This study explored whether curcumin improves colonic inflammation in a rat colitis model through inhibition of the TLR4/NF-κB signaling pathway and IL-27 expression. After induction of colitis with 2,4,6-trinitrobenzene sulfonic acid, rats were intragastrically administered with curcumin or sulfasalazine daily for one week. Rat intestinal mucosa was collected for evaluation of the disease activity index, colonic mucosa damage index, and histological score. Myeloperoxidase activity was detected by immunohistochemistry, and mRNA and protein expression levels of TLR4, NF-κB, and IL-27 in colonic mucosa were detected by RT-PCR and Western blot. Compared with the untreated colitis group, the curcumin-treated group showed significant decreases in the disease activity index, colonic mucosa damage index, histological score, myeloperoxidase activity, and expressions of NF-κB mRNA, IL-27 mRNA, TLR4 protein, NF-κB p65 protein, and IL-27 p28 protein (p < 0.05). TLR4 mRNA expression did not differ between groups. Disease activity index decreased more rapidly in the curcumin-treated group than in the sulfasalazine-treated group (p < 0.05). There was no significant difference in TLR4, NF-κB, and IL-27 mRNA and proteins between curcumin-treated and sulfasalazine-treated groups. Curcumin shows significant therapeutic effects on 2,4,6-trinitrobenzene sulfonic acid-induced colitis that are comparable to sulfasalazine. The anti-inflammatory actions of curcumin on colitis may involve inhibition of the TLR4/NF-κB signaling pathway and of IL-27 expression. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Curcumin; Disease Models, Animal; Gastrointestinal Agents; Inflammation; Interleukins; Intestinal Mucosa; Male; NF-kappa B; Peroxidase; Random Allocation; Rats; Signal Transduction; Sulfasalazine; Toll-Like Receptor 4; Transcription Factor RelA; Trinitrobenzenesulfonic Acid | 2013 |
Monotropein isolated from the roots of Morinda officinalis ameliorates proinflammatory mediators in RAW 264.7 macrophages and dextran sulfate sodium (DSS)-induced colitis via NF-κB inactivation.
We previously demonstrated that monotropein isolated from the roots of Morinda officinalis (Rubiaceae) has anti-inflammatory effects in vivo. In the present study, we investigated the molecular mechanisms underlying the anti-inflammatory effects of monotropein in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages and dextran sulfate sodium (DSS)-induced colitis mouse model. Monotropein was found to inhibit the expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) mRNA in LPS-induced RAW 264.7 macrophages. Treatment with monotropein decreased the DNA binding activity of nuclear factor-κB (NF-κB). Consistent with these findings, monotropein also suppressed phosphorylation and degradation of inhibitory κB-α (IκB-α), and consequently the translocations of NF-κB. In the DSS-induced colitis model, monotropein reduced disease activity index (DAI), myeloperoxidase (MPO) activity, and inflammation-related protein expressions by suppressing NF-κB activation in colon mucosa. Taken together, these findings suggest that the anti-inflammatory effects of monotropein are mainly related to the inhibition of the expressions of inflammatory mediators via NF-κB inactivation, and support its possible therapeutic role in colitis. Topics: Animals; Anti-Inflammatory Agents; Cell Line, Tumor; Colitis; Cyclooxygenase 2; Dextran Sulfate; I-kappa B Proteins; Inflammation Mediators; Interleukin-1beta; Iridoids; Lipopolysaccharides; Macrophages; Mice; Morinda; NF-kappa B; NF-KappaB Inhibitor alpha; Nitric Oxide Synthase Type II; Peroxidase; Phosphorylation; Plant Roots; RNA, Messenger; Tumor Necrosis Factor-alpha | 2013 |
Transplantation of granulocytic myeloid-derived suppressor cells (G-MDSCs) could reduce colitis in experimental murine models.
Myeloid-derived suppressor cells (MDSCs) are a group of myeloid cells expressing CD11b and Gr-1 marker in mice and comprise at least two subsets: granulocytic MDSCs (G-MDSCs) and monocytic MDSCs (M-MDSCs). This study aimed to evaluate the therapeutic efficacy of transplantation of G-MDSC subsets from normal mice to colitis mice.. Murine colitis model was induced by the intrarectal administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS). The mice were divided into four groups: control group, TNBS-induced colitis, TNBS-induced colitis plus normal saline injection and TNBS-induced colitis plus bone marrow-derived G-MDSCs injection (transplantation group). G-MDSCs were sorted and enriched via magnetic-activated cell sorting (MACS) program, the purity of the sorted cells was then identified using flow cytometry analysis. Sex cross-transplantation of dominant G-MDSCs was applied from normal mice to colitis models using i.v. injection. Changes of body weight, survival rate, myeloperoxidase (MPO) activity were monitored and macroscopic and microscopic injury scores are calculated. Donor cell Y chromosomes were assessed by in situ hybridization to assess reconstitutions.. After the transplantation of bone marrow-derived G-MDSCs from normal mice to colitis models, recipient mice showed increased survival rate, decreased macroscopic and microscopic injury scores and MPO activity, as well as lowered concentration of serum interleukin-6. Y chromosomes staining displayed colonization of donor cells of liver, spleen and colon tissues.. Bone marrow-derived G-MDSCs are effective in the improvement of murine colitis, but its effect in human needs further investigation. Topics: Animals; Body Weight; Colitis; Cytokines; Disease Models, Animal; Female; Graft Survival; Granulocytes; Inflammation Mediators; Male; Mice; Mice, Inbred BALB C; Myeloid Cells; Peroxidase; Trinitrobenzenesulfonic Acid | 2013 |
Loss of phosphoinositide 3-kinase P110γ is protective in the acute phase but detrimental in the resolution phase of hapten-induced colitis.
Pharmacologic inhibition or genetic ablation of phosphoinositide 3-kinase gamma (PI3Kγ) has been shown to be protective against experimental colitis. However, the role of PI3Kγ in the resolution phase of colitis remains unexplored. In this study, we assess the effects of genetic knockout of PI3Kγ on the induction and resolution of colitis induced by the hapten trinitrobenzene sulfonic acid (TNBS).. Colitis was induced in wild-type C57/Bl6 or PI3Kγ-/- mice by intrarectal administration of 2.5 mg of TNBS in 50% ethanol. Body weights were monitored daily, and colon tissues were collected at days 3, 7, or 14 after treatment, and colitis was assessed using disease activity and histologic damage scores, measurement of tissue myeloperoxidase and neutrophil infiltration, and local cytokine production.. Mice lacking PI3Kγ were significantly protected from disease during the acute phase (day 3) of TNBS colitis. However, PI3Kγ-/- mice have difficulty resolving acute inflammation because they failed to restore lost weight and had significantly elevated histologic damage scores and tissue myeloperoxidase levels at days 7 and 14 after TNBS administration compared with wild-type controls. This phenomenon was dependent on presensitization with TNBS and seems to involve an inability to clear invading bacteria, resulting in the generation of a persistent inflammatory cytokine response.. This study confirms that PI3Kγ plays a role in the induction of colitis. However, PI3Kγ is also required for the resolution of intestinal damage following acute inflammation. This must be taken into consideration before the inhibition of PI3Kγ can be used as a treatment for disorders such as inflammatory bowel disease. Topics: Acute Disease; Animals; Bacterial Translocation; Biomarkers; Chronic Disease; Class Ib Phosphatidylinositol 3-Kinase; Colitis; Cytokines; Fluorescent Antibody Technique; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; Peroxidase; Phagocytosis; Real-Time Polymerase Chain Reaction; Severity of Illness Index; Trinitrobenzenesulfonic Acid; Weight Loss | 2013 |
Anti-inflammatory intestinal activity of Arctium lappa L. (Asteraceae) in TNBS colitis model.
In Brazilian traditional medicine, Arctium lappa (Asteraceae), has been reported to relieve gastrointestinal symptoms.. In the present study, we investigated the effects of the lactone sesquiterpene onopordopicrin enriched fraction (ONP fraction) from Arctium lappa in an experimental colitis model induced by 2,4,6 trinitrobenzene sulfonic acid and performed experiments to elucidate the underlying action mechanisms involved in that effect.. ONP fraction (25 and 50 mg/kg/day) was orally administered 48, 24 and 1 h prior to the induction of colitis and 24 h after. The inflammatory response was assessed by gross appearance, myeloperoxidase (MPO) activity, tumor necrosis factor alpha (TNF-α) levels and a histological study of the lesions. We determined cyclooxygenase (COX)-1 and -2 protein expressions by western blotting and immunohistochemistry assays.. TNBS group was characterized by increased colonic wall thickness, edema, diffuse inflammatory cell infiltration, increased MPO activity and TNF-α levels. On the contrary, ONP fraction (25 and 50 mg/kg) treatment significantly reduced the macroscopic inflammation scores (p<0.05 and p<0.01, respectively) and morphological alterations associated with an increase in the mucus secretion. Similarly, the degree of neutrophil infiltration and the cytokine levels were significantly ameliorated. Moreover, COX-2 expression was up regulated in TNBS-treated rats. In contrast, ONP fraction (50 mg/kg) administration reduced COX-2 overexpression.. We have shown that the ONP fraction obtained from Arctium lappa exert marked protective effects in acute experimental colitis, confirming and justifying, at least in part, the popular use of this plant to treat gastrointestinal diseases. Topics: Animals; Anti-Inflammatory Agents; Arctium; Colitis; Cyclooxygenase 2; Disease Models, Animal; Male; Peroxidase; Phytotherapy; Plant Extracts; Plant Leaves; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2013 |
Quercetin-loaded microcapsules ameliorate experimental colitis in mice by anti-inflammatory and antioxidant mechanisms.
Quercetin (1) is an anti-inflammatory and antioxidant flavonoid. However, the oral administration of 1 did not lead to beneficial effects in experimental animal colitis models, which involve cytokines and oxidative stress. A possible explanation is that the absorption profile of 1 prevents its activity. Therefore, it was reasoned that the controlled release of 1 would improve its therapeutic effect. Thus, the therapeutic effect and mechanisms of 1-loaded microcapsules in acetic acid-induced colitis in mice were evaluated. Microcapsules were prepared using pectin/casein polymer and 1. The oral administration of 1-loaded microcapsules decreased neutrophil recruitment, attenuated histological alterations, and reduced macroscopical damage, edema, and IL-1β and IL-33 production in the colon samples. Microcapsules loaded with 1 also prevented the reduction of anti-inflammatory cytokine IL-10 and the antioxidant capacity of the colon. These preclinical data indicate that pectin/casein polymer microcapsules loaded with 1 improved the anti-inflammatory and antioxidant effects of 1 compared to the nonencapsulated drug. Therefore, quercetin seems to be a promising active molecule in inflammatory bowel disease if provided with adequate controlled release. Topics: Acetic Acid; Administration, Oral; Animals; Anti-Inflammatory Agents; Antioxidants; Capsules; Colitis; Disease Models, Animal; Drug Delivery Systems; Edema; Interleukin-1beta; Interleukin-33; Interleukins; Male; Mice; Molecular Structure; Neutrophils; Peroxidase; Quercetin | 2013 |
Arctigenin ameliorates inflammation in vitro and in vivo by inhibiting the PI3K/AKT pathway and polarizing M1 macrophages to M2-like macrophages.
Seeds of Arctium lappa, containing arctigenin and its glycoside arctiin as main constituents, have been used as a diuretic, anti-inflammatory and detoxifying agent in Chinese traditional medicine. In our preliminary study, arctigenin inhibited IKKβ and NF-κB activation in peptidoglycan (PGN)- or lipopolysaccharide (LPS)-induced peritoneal macrophages. To understand the anti-inflammatory effect of arctigenin, we investigated its anti-inflammatory effect in LPS-stimulated peritoneal macrophages and on LPS-induced systemic inflammation as well as 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Arctigenin inhibited LPS-increased IL-1β, IL-6 and TNF-α expression in LPS-stimulated peritoneal macrophages, but increased LPS-reduced IL-10 and CD204 expression. Arctigenin inhibited LPS-induced PI3K, AKT and IKKβ phosphorylation, but did not suppress LPS-induced IRAK-1 phosphorylation. However, arctigenin did not inhibit NF-κB activation in LPS-stimulated PI3K siRNA-treated peritoneal macrophages. Arctigenin suppressed the binding of p-PI3K antibody and the nucleus translocation of NF-κB p65 in LPS-stimulated peritoneal macrophages. Arctigenin suppressed blood IL-1β and TNF-α level in mice systemically inflamed by intraperitoneal injection of LPS. Arctigenin also inhibited colon shortening, macroscopic scores and myeloperoxidase activity in TNBS-induced colitic mice. Arctigenin inhibited TNBS-induced IL-1β, TNF-α and IL-6 expression, as well as PI3K, AKT and IKKβ phosphorylation and NF-κB activation in mice, but increased IL-10 and CD204 expression. However, it did not affect IRAK-1 phosphorylation. Based on these findings, arctigenin may ameliorate inflammatory diseases, such as colitis, by inhibiting PI3K and polarizing M1 macrophages to M2-like macrophages. Topics: Animals; Anti-Inflammatory Agents; Colitis; Cytokines; Furans; Lignans; Lipopolysaccharides; Macrophages, Peritoneal; Male; Mice; Mice, Inbred C57BL; Peroxidase; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Trinitrobenzenesulfonic Acid | 2013 |
Inhibition of p38/Mk2 signaling pathway improves the anti-inflammatory effect of WIN55 on mouse experimental colitis.
P38/Mk2 (mitogen-activated protein kinase (MAPK)-activated protein kinase-2, also known as MAKAP kinase-2) is a member of the mitogen-activated protein kinases (MAPKs) family, and participates in inflammatory responses directly or indirectly. WIN55, 212-2 (WIN55) is a synthetic non-selective agonist of cannabinoid (CB) receptors with remarkable anti-inflammatory properties. This study was to explore the roles of WIN55 and p38/Mk2 signaling pathway in dextran sodium sulfate (DSS)-induced mouse colitis and ascertain their anti-inflammatory mechanisms. Colitis was induced in C57BL Mk2 gene homozygous deletion (Mk2-/-) and wild-type mice by replacing the drinking water with 4% DSS solution for 7 days. DSS-treated mice developed bloody stool, weight loss, and eye-visible multiple bleeding ulcers on colon mucosa. The mRNA expressions levels of TNF-α and IL-6, as well as the protein levels of p38 and its phosphorylated form (p-p38), were upregulated in the colon. The plasma levels of TNF-α, IL-6, cytokine-induced neutrophil chemoattractant-1 (CINC-1), monocyte chemoattractant protein-1 (MCP-1), and lung myeloperoxidase (MPO) activities were raised; however, all these changes were less severe in Mk2-/- mice. After WIN55 intervention, the Mk2-/- mice recovered faster and better from the induced colitis than their wild-type counterparts. The results indicate that the Mk2 homozygous deletion in mice impedes the induction of experimental colitis by DSS, confirming the notion that p38/Mk2 is involved in this inflammatory response. WIN55 protects mice against DSS-induced colitis, in particular when the p38/Mk2 pathway is obstructed, implying that the activation of CB system, together with blocking of p38/Mk2 pathway, serves as a potential drug target for colitis treatment. Topics: Analysis of Variance; Animals; Anti-Inflammatory Agents; Benzoxazines; Chemokine CCL2; Chemokine CXCL1; Colitis; Dextran Sulfate; DNA Primers; Enzyme-Linked Immunosorbent Assay; Immunohistochemistry; Interleukin-6; Intracellular Signaling Peptides and Proteins; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Mice, Knockout; Morpholines; Naphthalenes; Peroxidase; Protein Serine-Threonine Kinases; Real-Time Polymerase Chain Reaction; Tumor Necrosis Factor-alpha | 2013 |
Intestinal anti-inflammatory activity of hydroalcoholic extracts of Phlomis purpurea L. and Phlomis lychnitis L. in the trinitrobenzenesulphonic acid model of rat colitis.
Different species from genus Phlomis, frequently native from the the eastern Mediterranean zone, have been used in traditional medicine as an anti-inflammatory remedy. Among other constituents, they contain polyphenols that show antioxidant properties, which are interesting for the treatment of inflammatory pathologies associated with oxidative stress in humans, such as inflammatory bowel disease (IBD). The aim of this study was to evaluate the intestinal anti-inflammatoy effect of hydroalcoholic extracts of Phlomis lychnitis and P. purpurea in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis, a well characterized experimental model with some resemblance to human IBD.. Hydroalcoholic extracts of both plants were characterized by determining their polyphenolic content and then assayed in the TNBS model of rat colitis. For this purpose, female Wistar rats were assigned to seven groups (n=10): healthy control, untreated TNBS-colitis and five TNBS- colitis groups treated with Phlomis lychnitis (10 and 20mg/kg), P. purpurea (10 and 25mg/kg) and sulphasalazine (200mg/kg), as a positive control. Treatments started the same day of TNBS colitis induction, and rats were sacrificed one week later. Colonic inflammation was evaluated both histologically and biochemically.. The histological (macroscopic and microscopic) analysis of colonic samples revealed that both extracts showed an anti-inflammatory effect, which was confirmed biochemically by a decreased colonic MPO activity, a maker of neutrophil infiltration, an increased colonic glutathione content, which counteracts the oxidative status associated with the inflammatory process, and a down-regulated iNOS expression. However, only the extract of P. purpurea reduced the expression of the proinflammatory cytokines IL-1β and IL-17, the chemokines CINC-1 and MCP-1, as well as the adhesion molecule ICAM-1, ameliorating the altered immune response associated with the colonic inflammation. Furthermore, both P. lychnitis and P. purpurea extracts were able to significantly increase the expression of markers of epithelial integrity such as MUC-2, MUC-3 and villin, thus revealing an improvement in the altered colonic permeability that characterizes colonic inflammation.. Both extracts showed intestinal anti-inflammatory activity in the TNBS model of rat colitis, thus confirming their traditional use in digestive inflammatory complaints. In addition to their antioxidant properties, other mechanisms can contribute to this beneficial effect, like an improvement in the intestine epithelial barrier and a downregulation of the immune response. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Cytokines; Disease Models, Animal; Female; Glutathione; Intestinal Mucosa; Mucins; Necrosis; Peroxidase; Phlomis; Plant Components, Aerial; Plant Extracts; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2013 |
Epicutaneous immunization with protein antigen TNP-Ig alleviates TNBS-induced colitis in mice.
Ulcerative colitis (UC) is a chronic inflammatory autoimmune disease with limited treatment modalities. The animal model of colitis induced by treatment with trinitrobenzene sulfonic acid (TNBS-colitis) is commonly used to test new therapies of this disease. In our previous work we found that epicutaneous (EC) immunization with protein antigen induced a state of profound immunosuppression that inhibited inflammatory response in contact sensitivity, in experimental autoimmune encephalomyelitis (EAE) and in allogeneic skin graft rejection.. TNBS-induced colitis was used as an experimental model.. In our current work, we showed that EC immunization with TNP-conjugated mouse immunoglobulin (TNP-Ig) prior to induction of TNBS-colitis alleviates disease severity what was determined by the body weight, the length and the weight of the colon, the histological activity index (HAI) and myeloperoxidase activity (MPO). Observed amelioration of the disease in TNP-Ig patched mice was accompanied with decreased production of IFN-γ and IL-17A by splenocytes. Additionally, spleen cells isolated from mice EC immunized with TNP-Ig prior to colitis induction showed increased production of IL-10 suggesting that this cytokine might be involved in inhibiting inflammatory response in the colon.. This work shows that EC immunization with protein antigen prior to TNBS-colitis induction ameliorates disease and observed suppression of inflammatory response in the colon might be mediated by IL-10. Topics: Administration, Cutaneous; Animals; Biomarkers; Cells, Cultured; Colitis; Colon; Desensitization, Immunologic; Disease Models, Animal; Female; Immunoglobulins; Inflammation Mediators; Interferon-gamma; Interleukin-10; Interleukin-17; Mice; Neutrophils; Peroxidase; Severity of Illness Index; Skin; Spleen; Time Factors; Transdermal Patch; Trinitrobenzenes; Trinitrobenzenesulfonic Acid | 2012 |
Effect of hydroalcoholic extract of Hibiscus rosa sinensis Linn. leaves in experimental colitis in rats.
To elucidate the ameliorative effect of hydroalcoholic extract of leaves of Hibiscus rosa sinensis (HRS) in acetic acid induced experimental colitis in male wistar rats.. The animals were administered with 2 mL acetic acid (4%) via intra rectal. The animals were divided into various treatment groups (n=6). Prednisolone was used as standard drug and HRS was administered at a dose of 50, 100 and 200 mg/kg p.o. The control group of animals received 1 mL of vehicle (distilled water). Ulcer area, ulcer index, spleen weight, colon weight to length ratio, macroscopic score, haematological parameters, colonic superoxide dismutase (SOD), glutathione (GSH), myeloperoxidase (MPO), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), nitric oxide (NO) and histological changes were recorded after the treatment regimen of 11 days.. Intrarectal instillation of acetic acid caused enhanced ulcer area, ulcer index, spleen weight, colon weight to length ratio, colonic MPO, MDA, NO and TNF-α It caused significant decreased level of SOD and GSH. Pretreatment with HRS for 7 days exhibited significant effect in lowering of oxidative stress, colonic NO, TNF-α and elevation of SOD and GSH at a dose of 100 and 200 mg/kg in acetic acid induced colitis.. The present investigation demonstrates HRS is of potent therapeutic value in the amelioration of experimental colitis in laboratory animals by inhibiting the proinflammatory mediator like NO and TNF-α. Topics: Acetic Acid; Animals; Colitis; Colon; Disease Models, Animal; Glutathione; Hibiscus; Male; Malondialdehyde; Nitric Oxide; Organ Size; Oxidative Stress; Peroxidase; Phytotherapy; Plant Leaves; Plant Preparations; Rats; Rats, Wistar; Superoxide Dismutase; Tumor Necrosis Factor-alpha | 2012 |
Effects of glucagon-like peptide-2 on bacterial translocation in rat models of colitis.
The aim of this trial was to study the role of glucagon-like peptide-2 in reducing bacterial translocation by virtue of its anti-inflammatory effects and ability to decrease intestinal permeability in rat models of inflammatory bowel diseases. On the basis of our results and those of other recent studies, we suggest a new treatment modality for colitis. To our knowledge, this is the first study of the effectiveness of glucagon-like peptide-2 on bacterial translocation, in treating an experimental colitis model.. Rats were randomized into 3 groups of 7 rats each-the control group, colitis group, and treatment group. On the 7 th day after induction of colitis, the levels of tissue myeloperoxidase, serum tumor necrosis factor-alpha, and plasma endotoxin were measured. Tissue samples were obtained from the liver, spleen, and mesenteric lymph nodes for evaluating bacterial translocation.. Bacterial translocation in samples of the liver, spleen, mesenteric lymph nodes, and portal and systemic blood obtained from the treatment group was lower than that in samples obtained from the colitis group (p < 0.05). The levels of tissue myeloperoxidase, serum tumor necrosis factor-alpha, and plasma endotoxin in the treatment group were significantly lower than those in the colitis group (p < 0.05).. In experimental colitis models, which were induced using trinitrobenzene sulfonic acid in ethanol, glucagon-like peptide-2 treatment reduced inflammation and bacterial translocation from the intestinal mucosa. Our results indicate that glucagon-like peptide-2 is a potential agent for treating colitis; however, extensive trials are needed to confirm our results. Topics: Animals; Bacterial Translocation; Colitis; Colon; Disease Models, Animal; Endotoxins; Glucagon-Like Peptide 2; Male; Peroxidase; Random Allocation; Rats; Rats, Wistar; Treatment Outcome; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2012 |
Dietary kaempferol suppresses inflammation of dextran sulfate sodium-induced colitis in mice.
In ulcerative colitis (UC), reduction of inflammation may represent a key mechanism in UC therapy, and anti-inflammatory agents would be good candidates for preventing UC. Kaempferol, a natural flavonoid, is believed to have anti-inflammatory activities and has been shown to be potentially immune-modulatory.. The aim of this study was to determine whether kaempferol alleviates the inflammatory responses of dextran sulfate sodium (DSS)-induced colitis in mice.. Female C57BL/6J mice were divided into six groups: a negative control group, a DSS control group, and DSS + 0.1% or 0.3% kaempferol pre- or post-fed groups. At the end of the experimental period, clinical and biochemical markers were evaluated.. Plasma levels of NO and PGE(2) were significantly decreased in both the 0.3% kaempferol pre- and post-fed groups. The plasma LTB(4) level was profoundly decreased in all animals fed kaempferol. Colonic mucosa MPO activity was also suppressed in both the 0.3% kaempferol pre- or post-fed groups. TFF3 mRNA, a marker for goblet cell function, was up-regulated in kaempferol pre-fed animals.. These results indicate that kaempferol is an effective anti-inflammatory agent that protects colonic mucosa from DSS-induced UC. Dietary kaempferol fed prior to colitis induction was more effective to suppress some of the colitis-associated markers. Topics: Animals; Colitis; Colon; Cyclooxygenase 2; Dextran Sulfate; Female; Immunohistochemistry; Kaempferols; Mice; Mice, Inbred C57BL; Mucins; Peroxidase; Trefoil Factor-3 | 2012 |
Human neutrophil peptide-1 aggravates dextran sulfate sodium-induced colitis.
Human neutrophil peptide (HNP)-1, HNP-2, and HNP-3 (HNP-1-3) are useful biomarkers for ulcerative colitis (UC). The precise roles of these peptides in UC are poorly understood, however. The aim of this study was to determine whether HNP-1 affects disease activity in mice with experimental colitis.. Experimental colitis was induced in BALB/c or severe combined immunodeficiency (SCID) mice using dextran sulfate sodium (DSS). Mice were subsequently treated intraperitoneally with HNP-1 (100 μg/day) or phosphate-buffered saline (PBS) from day 4 to day 6. The severity of colitis was evaluated based on a disease activity index, histologic score, and cytokine expression.. Body weight and colon length significantly decreased and the disease activity index score, histologic score, and myeloperoxidase activity significantly increased in HNP-1-treated BALB/c mice compared with PBS-treated mice. Interferon-γ and tumor necrosis factor-α levels in colon culture supernatants-derived HNP-1-treated mice were also significantly higher, and interleukin (IL)-1β levels tended to increase in response to HNP-1. In addition, treating SCID mice with HNP-1 aggravated DSS-induced colitis and IL-1β levels in colon culture supernatants from these mice were significantly higher than in cultures obtained from control mice. Furthermore, in both BALB/c and SCID mice increased recruitment of F4/80-positive macrophages was observed in the inflamed colonic mucosa following HNP-1 injections.. High concentrations of HNP-1 aggravate DSS-induced colitis, including upregulated expression of such macrophage-derived cytokines as IL-1β. These results indicate that high concentrations of HNP-1-3 in patients with UC may exacerbate disease activity via increased cytokine production. Topics: alpha-Defensins; Animals; Cells, Cultured; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Humans; Interferon-gamma; Interleukin-1beta; Intestinal Mucosa; Macrophages; Male; Mice; Mice, Inbred BALB C; Mice, SCID; Peroxidase; Severity of Illness Index; Tumor Necrosis Factor-alpha; Up-Regulation | 2012 |
Toll-like receptor-7 ligand Imiquimod induces type I interferon and antimicrobial peptides to ameliorate dextran sodium sulfate-induced acute colitis.
The pathogenesis of inflammatory bowel disease (IBD) is associated with a dysregulated mucosal immune response. Certain stimulators of innate immunity (CpG DNA or GM-CSF) are reported to be anti-inflammatory in IBD. Toll-like receptor-7 (TLR7) is an important regulator of innate immunity and its activation plays a key role in induction of type I interferon (IFN). The present study tests the hypothesis that the TLR7 agonists Imiquimod has therapeutic efficacy in IBD.. Acute colitis was induced in Balb/c mice by giving 5% dextran sodium sulfate (DSS) in drinking water for 7 days. Mice were treated with Imiquimod either orally or topically and its therapeutic effects on disease activity were examined. Isolated mouse CD11c+ dendritic cells and human intestinal epithelial cells (HT29, HCT116) were treated with Imiquimod (10 μg/mL) and their susceptibility to intracellular Salmonella typhimurium infection was assessed by gentamicin protection assay.. Oral administration of Imiquimod induced type I IFN expression in the gastrointestinal mucosa and ameliorated DSS-induced acute colitis as assessed by clinical parameters, histology, and mRNA expression of proinflammatory cytokines. Topical administration of Imiquimod also ameliorated DSS colitis by inducing the expression of type I IFN in the colonic mucosa. However, no evidence for a systemic IFN response was observed. Imiquimod treatments to both CD11c+ and intestinal epithelial cells significantly increased expression of antimicrobial peptides (AMPs) and reduced survival of intracellular S. typhimurium.. Imiquimod induces type I IFN and AMP to ameliorate DSS-induced acute colitis and prevents Salmonella survival. Therefore, Imiquimod treatments provide a new therapeutic approach for IBD patients. Topics: Administration, Oral; Administration, Topical; Aminoquinolines; Animals; Antimicrobial Cationic Peptides; Biomarkers; Colitis; Cytokines; Dextran Sulfate; Female; Gastrointestinal Tract; Gene Expression Profiling; Humans; Imiquimod; Interferon Inducers; Interferon Type I; Mice; Mice, Inbred BALB C; Oligonucleotide Array Sequence Analysis; Peroxidase; Real-Time Polymerase Chain Reaction; RNA, Messenger; Salmonella Infections; Salmonella typhimurium; Survival Rate; Toll-Like Receptor 7 | 2012 |
Salvinorin A has antiinflammatory and antinociceptive effects in experimental models of colitis in mice mediated by KOR and CB1 receptors.
Salvinorin A (SA) has a potent inhibitory action on mouse gastrointestinal (GI) motility and ion transport, mediated primarily by kappa-opioid receptors (KOR). The aim of the present study was to characterize possible antiinflammatory and antinociceptive effects of SA in the GI tract of mice.. Colonic damage scores and myeloperoxidase activity were determined after intraperitoneal (i.p.), intracolonic (i.c.), and oral (p.o.) administration of SA using the trinitrobenzene sulfonic acid (TNBS) and dextran sodium sulfate (DSS) models of colitis in mice. Additionally, KOR, cannabinoid (CB)1, and CB2 western blot analysis of colon samples was performed. The antinociceptive effect of SA was examined based on the number of behavioral responses to i.c. instillation of mustard oil (MO).. The i.p. (3 mg/kg, twice daily) and p.o. (10 mg/kg, twice daily) administration of SA significantly attenuated TNBS and DSS colitis in mice. The effect of SA was blocked by KOR antagonist nor-binaltorphimine (10 mg/kg, i.p.). Western blot analysis showed no influence of SA on KOR, CB1, or CB2 levels. SA (3 mg/kg, i.p. and 10 mg/kg, i.c.) significantly decreased the number of pain responses after i.c. instillation of MO in the vehicle- and TNBS-treated mice. The antinociceptive action of SA was blocked by KOR and CB1 antagonists. The analgesic effect of i.c. SA was more potent in TNBS-treated mice compared to controls.. Our results suggest that the drugs based on the structure of SA have the potential to become valuable antiinflammatory or analgesic therapeutics for the treatment of GI diseases. Topics: Analgesics; Animals; Anti-Inflammatory Agents; Blotting, Western; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Diterpenes, Clerodane; Gastrointestinal Motility; Male; Mice; Naltrexone; Pain; Peroxidase; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Receptors, Opioid, kappa; Salvia; Trinitrobenzenesulfonic Acid | 2012 |
Aminoguanidine and curcumin attenuated tumor necrosis factor (TNF)-α-induced oxidative stress, colitis and hepatotoxicity in mice.
The up regulation of gut mucosal cytokines such as tumor necrosis factor (TNF)-α and oxidative stress have been related to inflammatory bowel diseases (IBD) such as ulcerative colitis (UC) and Crohn's disease (CD). This study investigated an immune-mediated model of colitis. TNF-α injected intraperitonally to mice induced a dose-dependent recruitment of neutrophils into abdominal mesentery. The leukocytes influx induced by TNF-α (10 μg kg(-1) body weight) increased by 3 fold liver and colon damage scores. TNF-α-colitis was characterized by hemorrhagic edemas and crypt abscesses massively infiltrated by inflammatory cells, namely neutrophils. Moreover, TNF-α-toxicity resulted in liver steatosis and foci of necrosis infiltrated by Kupffer cells and neutrophils in parenchyma and around the centrilobular veins. The involvement of oxidative stress was evaluated using aminoguanidine (AG) as selective inhibitor of inducible NO synthase (iNOS) and curcumin (Cur), the polyphenolic antioxidant of turmeric (Curcuma longa L.). TNF-α-toxicity led to significant increase in myeloperoxidase (MPO, an index of neutrophils infiltration), nitrites (stable nitric oxide metabolites) and malondialdehyde (MDA, a marker of lipid peroxides) levels and cell apoptosis in liver and colon. AG and Cur treatments significantly attenuated the hallmarks of oxidative stress, neutrophils influx and ROS-related cellular and histological damages, in TNF-α-treated mice. Taken together, our results provide insights into the role of phagocytes-derived oxidants in TNF-α-colitis in mice. Cur and AG, by inhibiting neutrophils priming and iNOsynthase could be effective against oxidative bowel damages induced in IBD by imbalanced gut immune response. Topics: Animals; Antioxidants; Apoptosis; Colitis; Curcumin; Guanidines; Liver; Male; Mice; Neutrophils; Nitric Oxide; Nitric Oxide Synthase Type II; Oxidative Stress; Peroxidase; Tumor Necrosis Factor-alpha | 2012 |
Suppression of TNBS-induced colitis in rats by 4-methylesculetin, a natural coumarin: comparison with prednisolone and sulphasalazine.
The aim of the present study was to compare the effects of the 4-methylesculetin with those produced by prednisolone and sulphasalazine and to elucidate the mechanisms involved in its action. Colitis was induced in rat by instillation of trinitrobenzenesulphonic acid (TNBS). The colon damage was evaluated using macroscopic, microscopic and biochemical analysis. In addition, in vitro studies were performed to evaluate cytokine production in cell cultures using the murine macrophage cell line RAW264.7, mouse splenocytes and the human colonic epithelial cell line Caco-2. 4-Methylesculetin produced a reduction of the macroscopic damage score and the recovery of the intestinal cytoarchitecture. These effects were associated with a prevention of the GSH depletion and an inhibition in AP activity. After colitis relapse, 4-methylesculetin improved the colonic inflammatory status as evidenced by histological findings, with a reduction in apoptosis, as well as biochemically by inhibition of colonic myeloperoxidase, alkaline phosphatase and metalloproteinase 9 activities. Paired with this inhibitive activity, there was a decrease in malondialdehyde content and in IL-1β levels. In vitro assays revealed that 4-methylesculetin promoted an inhibition in IL-1β, IL-8, IL-2 and IFN-γ production in cell cultures. In conclusion, 4-methylesculetin showed similar efficacy to that obtained with either prednisolone or sulphasalazine, both in the acute phase of colitis as well as following a curative protocol. The intestinal anti-inflammatory activity by 4-methylesculetin is likely related to its ability in reduce colonic oxidative stress and inhibit pro-inflammatory cytokine production. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Apoptosis; Cell Line; Colitis; Coumarins; Cytokines; Gene Expression Regulation; Glutathione; Humans; Male; Malondialdehyde; Matrix Metalloproteinase 9; Mice; Peroxidase; Prednisolone; Rats; Rats, Wistar; Recurrence; Sulfasalazine; Trinitrobenzenesulfonic Acid; Umbelliferones | 2012 |
Pretreatment with alanyl-glutamine suppresses T-helper-cell-associated cytokine expression and reduces inflammatory responses in mice with acute DSS-induced colitis.
T-helper (Th) cells play a major role in initiating and shaping the pathologic response in inflammatory bowel disease (IBD). Glutamine (GLN) is a nutrient with immune-modulating effects. This study investigated the effect of GLN on cytokine expressions and inflammatory responses of three subsets of Th cells in dextran sulfate sodium (DSS)-induced IBD. There were one normal control (NC) and two DSS groups. Mice in the DSS groups drank distilled water containing 3% DSS for 5 days, whereas the NC group received distilled water. Mice in the G-DSS group were given intraperitoneal injection of 0.5 g GLN/kg/d for 3 days before receiving DSS water. The other DSS group (C-DSS) received an identical amount of amino acid solution without GLN. After induction of IBD, the mice were allowed to recover for 3 days and then were sacrificed. Blood and colon samples were collected for further analysis. The C-DSS group had higher percentages of blood interleukin (IL)-17A, IL-17F, IL-22, IL-4 and interferon-γ than the NC group. The G-DSS group had lower Th1/Th17/Th2 cytokine expressions, which showed no differences from the NC group. Plasma haptoglobin, colon immunoglobin G and chemokine levels and myeloperoxidase activities were higher in the DSS groups than the NC group. These parameters were significantly lower in the G-DSS than the C-DSS group. These results suggest that pretreatment with GLN suppressed Th-associated cytokine expressions and may consequently reduce inflammatory mediator production and leukocyte infiltration into tissues, thus ameliorating the severity of acute DSS-induced colitis. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colitis, Ulcerative; Colon; Cytokines; Dextran Sulfate; Dipeptides; Disease Models, Animal; Down-Regulation; Haptoglobins; Inflammatory Bowel Diseases; Injections, Intraperitoneal; Intestinal Mucosa; Male; Mice; Mice, Inbred C57BL; Peroxidase; Severity of Illness Index; T-Lymphocytes, Helper-Inducer | 2012 |
Constitutive TL1A expression under colitogenic conditions modulates the severity and location of gut mucosal inflammation and induces fibrostenosis.
Intestinal fibrostenosis is a hallmark of severe Crohn's disease and can lead to multiple surgeries. Patients with certain TNFSF15 variants overexpress TL1A. The aim of this study was to determine the effect of TL1A overexpression on intestinal inflammation and the development of fibrostenosis. We assessed the in vivo consequences of constitutive TL1A expression on gut mucosal inflammation and fibrostenosis using two murine models of chronic colitis. In the dextran sodium sulfate (DSS) and adoptive T-cell transfer models, there was proximal migration of colonic inflammation, worsened patchy intestinal inflammation, and long gross intestinal strictures in Tl1a transgenic compared to wild-type littermates. In the DSS model, myeloid- and T-cell-expressing Tl1a transgenic mice had increased T-cell activation markers and interleukin-17 expression compared to wild-type mice. In the T-cell transfer model, Rag1(-/-) mice receiving Tl1a transgenic T cells had increased interferon-γ expression but reduced T-helper 17 cells and IL-17 production. Narrowed ureters with hydronephrosis were found only in the Tl1a transgenic mice in all chronic colitis models. In human translational studies, Crohn's disease patients with higher peripheral TL1A expression also exhibited intestinal fibrostenosis and worsened ileocecal inflammation with relative sparing of rectosigmoid inflammation. These data show that TL1A is an important cytokine that not only modulates the location and severity of mucosal inflammation, but also induces fibrostenosis. Topics: Adoptive Transfer; Animals; Chronic Disease; Colitis; Colon; Constriction, Pathologic; Fibrosis; Humans; Interleukin-17; Intestinal Mucosa; Lymphocyte Activation; Mice; Mice, Transgenic; Peroxidase; T-Lymphocytes; Tumor Necrosis Factor Ligand Superfamily Member 15 | 2012 |
Distinct compartmentalization of NF-κB activity in crypt and crypt-denuded lamina propria precedes and accompanies hyperplasia and/or colitis following bacterial infection.
Citrobacter rodentium induces transmissible murine colonic hyperplasia (TMCH) and variable degrees of inflammation and necrosis depending upon the genetic background. Utilizing C. rodentium-induced TMCH in C3H/HeNHsd inbred mice, we observed significant crypt hyperplasia on days 3 and 7 preceding active colitis. NF-κB activity in the crypt-denuded lamina propria (CLP) increased within 24 h postinfection, followed by its activation in the crypts at day 3, which peaked by day 7. Increases in interleukin-α1 (IL-1α), IL-12(p40), and macrophage inflammatory protein 1α (MIP-1α) paralleled NF-κB activation, while increases in IL-1α/β, IL-6/IL-12(p40)/granulocyte colony-stimulating factor (G-CSF)/keratinocyte-derived chemokine (KC)/monocyte chemotactic protein 1 (MCP-1), and MIP-1α followed NF-κB activation leading to significant recruitment of neutrophils to the colonic mucosa and increased colonic myeloperoxidase (MPO) activity. Phosphorylation of the crypt cellular and nuclear p65 subunit at serines 276 and 536 led to functional NF-κB activation that facilitated expression of its downstream target, CXCL-1/KC, during TMCH. Distinct compartmentalization of phosphorylated extracellular signal-regulated kinase 1 and 2 ([ERK1/2] Thr(180)/Tyr(182)) and p38 (Thr(202)/Tyr(204)) in the CLP preceded increases in the crypts. Inhibition of ERK1/2 and p38 suppressed NF-κB activity in both crypts and the CLP. Dietary administration of 6% pectin or 4% curcumin in C. rodentium-infected mice also inhibited NF-κB activity and blocked CD3, F4/80, IL-1α/β, G-CSF/MCP-1/KC, and MPO activity in the CLP while not affecting NF-κB activity in the crypts. Thus, distinct compartmentalization of NF-κB activity in the crypts and the CLP regulates crypt hyperplasia and/or colitis, and dietary intervention may be a novel strategy to modulate NF-κB-dependent protective immunity to facilitate crypt regeneration following C. rodentium-induced pathogenesis. Topics: Animals; Cells, Cultured; Citrobacter rodentium; Colitis; Cytokines; Diet; Enterobacteriaceae Infections; Female; Gene Expression Regulation; Hyperplasia; Intestinal Mucosa; Male; Mice; Mice, Inbred C3H; Mucous Membrane; NF-kappa B; Peroxidase | 2012 |
Aloysia triphylla infusion protects rats against dextran sulfate sodium-induced colonic damage.
Inflammatory bowel diseases consist of uncontrolled intestinal inflammation leading to mucosal disruption. Polyphenols are micronutrients with antioxidant and anti-inflammatory properties and may play an interesting role in the prevention of intestinal inflammation. Lemon verbena (Aloysia triphylla (L'Herit.) Britton, Verbenaceae) infusion is a popular herbal drink rich in polyphenols. This study evaluated the protective effects of lemon verbena infusion consumption on the development of dextran sulfate sodium (DSS)-induced colitis in rats. The infusion was given to rats as a drink providing 82 µmol polyphenols day(-1) for 21 days. Colitis was induced with 40 g l(-1) DSS in the drink for the last 7 days.. Lemon verbena infusion treatment restored body weight gain and prevented colonic shortening. Despite no protective effect on myeloperoxidase activity, A. triphylla infusion limited histological colonic alterations.. The results suggest that lemon verbena infusion partially protects rats against DSS-induced inflammation. Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Colon; Dextran Sulfate; Male; Peroxidase; Phytotherapy; Plant Extracts; Polyphenols; Rats; Rats, Wistar; Verbenaceae; Weight Gain | 2012 |
Ginsenoside Rd attenuates the inflammatory response via modulating p38 and JNK signaling pathways in rats with TNBS-induced relapsing colitis.
In this study, we investigated the effects and the protective mechanism of ginsenoside Rd (GRd) which has been identified as one of the effective compounds from ginseng on relapsing colitis model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats. After inducing relapsing colitis in experimental rats on two occasions by intracolonic injection of TNBS, GRd (10, 20 and 40 mg/kg) was administered to experimental colitis rats for 7 days. The inflammatory degree was assessed by macroscopic score, histology and myeloperoxidase (MPO) activity. The levels of proinflammatory cytokines, such as TNF-α, IL-1β, and IL-6 were determined by ELISA. Mitogen-activated protein kinase (MAPK) phosphorylation was analyzed by western blotting method. The results showed that GRd markedly attenuates the inflammatory response to TNBS-induced relapsing colitis, as evidenced by improved signs, increased body weight, decreased colonic weight/length ratio, reduced colonic macroscopic and microscopic damage scores, inhibited the activity of MPO, lowered proinflammatory cytokine levels and suppressed phosphorylation of p38 and JNK. The possible mechanism of protection on experimental colitis after GRd administration was that it could reduce the accumulation of leukocytes and down-regulate multiple proinflammatory cytokines through modulation of JNK and p38 activation. Topics: Animals; Body Weight; Colitis; Colon; Down-Regulation; Ginsenosides; Interleukin-1beta; Interleukin-6; Leukocytes; Male; MAP Kinase Kinase 4; MAP Kinase Signaling System; Mitogen-Activated Protein Kinases; p38 Mitogen-Activated Protein Kinases; Peroxidase; Phosphorylation; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2012 |
Green tea polyphenol epigallocatechin-3-gallate shows therapeutic antioxidative effects in a murine model of colitis.
Leukocyte infiltration, up-regulation of proinflammatory cytokines and severe oxidative stress caused by increased amounts of reactive oxygen species are characteristics of inflammatory bowel disease. The catechin (2R,3R)-2-(3,4,5-Trihydroxyphenyl)-3,4-dihydro-1(2H)-benzopyran-3,5,7-triol-3-(3,4,5-trihydroxybenzoate), named epigallocatechin-3-gallate, EGCG, has been demonstrated to exert anti-inflammatory and antioxidative properties, reducing reactive oxygen species in the inflamed tissues. The aim of this study was to evaluate the therapeutic effects of EGCG in a murine model of colitis induced by oral administration of dextran sodium sulfate.. Mice received a daily oral administration of 6.9 mg/kg body weight EGCG or Piper nigrum (L.) alkaloid (2E,4E)-5-(1,3-benzodioxol-5-yl)-1-piperidin-1-ylpenta-2,4-dien-1-one, named piperine (2.9 mg/kg body weight) or the combination of the both - piperine was used in this combination to enhance the bioavailability of EGCG.. In vivo data revealed the combination of EGCG and piperine to significantly reduce the loss of body weight, improve the clinical course and increase overall survival in comparison to untreated groups. The attenuated colitis was associated with less histological damages to the colon and reduction of tissue concentrations of malondialdehyde, the final product of lipid peroxidation. Neutrophils accumulation indicator myeloperoxidase was found to be reduced in colon tissue, while antioxidant enzymes like superoxide dismutase and glutathione peroxidase showed an increased activity. In vitro, the treatment with EGCG plus piperine enhanced the expression of SOD as well as GPO and also reduced the production of proinflammatory cytokines.. These data support the concept of anti-inflammatory properties of EGCG being generally beneficial in the DSS-model of colitis, an effect that may be mediated by its strong antioxidative potential. Topics: Alkaloids; Analysis of Variance; Animals; Antioxidants; Benzodioxoles; Catechin; Colitis; Dextran Sulfate; Female; Glutathione Peroxidase; HT29 Cells; Humans; Interleukin-8; Malondialdehyde; Mice; Mice, Inbred C57BL; Oxidative Stress; Peroxidase; Piperidines; Polyunsaturated Alkamides; Reactive Oxygen Species; Superoxide Dismutase; Weight Loss | 2012 |
Investigating intestinal inflammation in DSS-induced model of IBD.
Inflammatory bowel disease (IBD) encompasses a range of intestinal pathologies, the most common of which are ulcerative colitis (UC) and Crohn's Disease (CD). Both UC and CD, when present in the colon, generate a similar symptom profile which can include diarrhea, rectal bleeding, abdominal pain, and weight loss.(1) Although the pathogenesis of IBD remains unknown, it is described as a multifactorial disease that involves both genetic and environmental components.(2) There are numerous and variable animal models of colonic inflammation that resemble several features of IBD. Animal models of colitis range from those arising spontaneously in susceptible strains of certain species to those requiring administration of specific concentrations of colitis-inducing chemicals, such as dextran sulphate sodium (DSS). Chemical-induced models of gut inflammation are the most commonly used and best described models of IBD. Administration of DSS in drinking water produces acute or chronic colitis depending on the administration protocol.(3) Animals given DSS exhibit weight loss and signs of loose stool or diarrhea, sometimes with evidence of rectal bleeding.(4,5) Here, we describe the methods by which colitis development and the resulting inflammatory response can be characterized following administration of DSS. These methods include histological analysis of hematoxylin/eosin stained colon sections, measurement of pro-inflammatory cytokines, and determination of myeloperoxidase (MPO) activity, which can be used as a surrogate marker of inflammation.(6) The extent of the inflammatory response in disease state can be assessed by the presence of clinical symptoms or by alteration in histology in mucosal tissue. Colonic histological damage is assessed by using a scoring system that considers loss of crypt architecture, inflammatory cell infiltration, muscle thickening, goblet cell depletion, and crypt abscess.(7) Quantitatively, levels of pro-inflammatory cytokines with acute inflammatory properties, such as interleukin (IL)-1β, IL-6 and tumour necrosis factor (TNF)-α,can be determined using conventional ELISA methods. In addition, MPO activity can be measured using a colorimetric assay and used as an index of inflammation.(8) In experimental colitis, disease severity is often correlated with an increase in MPO activity and higher levels of pro-inflammatory cytokines. Colitis severity and inflammation-associated damage can be assessed by examining stool consistenc Topics: Animals; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Inflammatory Bowel Diseases; Male; Mice; Mice, Inbred C57BL; Peroxidase | 2012 |
β-Casein hydrolysate generated by the cell envelope-associated proteinase of Lactobacillus delbrueckii ssp. lactis CRL 581 protects against trinitrobenzene sulfonic acid-induced colitis in mice.
Lactobacillus delbrueckii ssp. lactis CRL 581, a thermophilic lactic acid bacterium used as a starter culture for the manufacture of several fermented dairy products, possesses an efficient proteolytic system that is able to release a series of potentially bioactive peptides (i.e., antihypertensive and phosphopeptides) from α- and β-caseins. Considering the potential beneficial health effects of the peptides released by L. delbrueckii ssp. lactis CRL 581 from milk proteins, the aim of this work was to analyze the anti-mutagenic and anti-inflammatory properties of the casein hydrolysates generated by the cell envelope-associated proteinase of this bacterium. The ability of α- and β-casein hydrolysates to suppress the mutagenesis of a direct-acting mutagen 4-nitroquinoline-N-oxide on Salmonella typhimurium TA 98 and TA 100 increased concomitantly with the time of casein hydrolysis. The anti-inflammatory effect of the β-casein hydrolysate was evaluated using a trinitrobenzene sulfonic acid (TNBS)-induced Crohn's disease murine model. The hydrolysate was administered to mice 10 d before the intrarectal inoculation of TNBS. The mice that received β-casein hydrolysate previously to TNBS showed decreased mortality rates, faster recovery of initial body weight loss, less microbial translocation to the liver, decreased β-glucuronidase and myeloperoxidase activities in the gut, and decreased colonic macroscopic and microscopic damage compared with the animals that did not receive this hydrolysate. In addition, β-casein hydrolysate exerted a beneficial effect on acute intestinal inflammation by increased interleukin 10 and decreased IFN-γ production in the gut. Our findings are consistent with the health-promoting attributes of the milk products fermented by L. delbrueckii ssp. lactis CRL 581 and open up new opportunities for developing novel functional foods. Topics: Animals; Antimutagenic Agents; Caseins; Colitis; Disease Models, Animal; Female; Glucuronidase; Lactobacillus delbrueckii; Mice; Mice, Inbred BALB C; Mutagenicity Tests; Peroxidase; Protein Hydrolysates; Trinitrobenzenesulfonic Acid | 2012 |
Bioadhesive pellets increase local 5-aminosalicylic acid concentration in experimental colitis.
Topical delivery of 5-aminosalicylic acid (5-ASA) to the colonic mucosa is important in order to achieve effective drug concentration in the site of inflammation and to minimize its systemic availability. 5-ASA loaded pellets were prepared by an extrusion/spheronization method. Mucoadhesive biopolymer chitosan was incorporated into the pellets, and drug delivery to the colon was controlled by the pH-sensitive polymer Eudragit® FS. Dissolution profiles of coated pellets revealed no drug release at pH 1.2 within 2h and release as intended in the simulated distal ileum and colon. In vivo, chitosan-core drug loaded pellets (AMCh) showed 2.5-fold higher drug metabolite concentration than after chitosan free pellets (AM) administration in the inflamed colonic tissue. Additionally, AMCh demonstrated decreased in AUC in colitis group (1507 ± 400 ng h/ml) compared with AM (1907 ± 122 ng h/ml). In terms of therapeutic efficiency, administration of pellets markedly decreased the colon/body weight ratio (colitis: 0.0355 ± 0.0028; AM 0.0092 ± 0.0033; AMCh 0.0086 ± 0.0022) and myeloperoxidase activity (colitis: 3212 ± 294 U/g tissue; AM 796 ± 211 U/g; AMCh 552 ± 319 U/g). Bioadhesive chitosan pellets showed additional beneficial properties for colonic 5-ASA delivery in the treatment of inflammatory bowel disease by increasing the drug concentration locally. Topics: Animals; Anti-Inflammatory Agents; Biopolymers; Chitosan; Colitis; Colon; Drug Delivery Systems; Drug Implants; Hydrogen-Ion Concentration; Inflammation; Male; Mesalamine; Particle Size; Peroxidase; Rats; Rats, Wistar; Solubility | 2012 |
Topical and systemic cannabidiol improves trinitrobenzene sulfonic acid colitis in mice.
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.. 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.. 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.. 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. Topics: Administration, Oral; Administration, Rectal; Administration, Topical; Animals; Anti-Inflammatory Agents; Cannabidiol; Colitis; Disease Models, Animal; Injections, Intraperitoneal; Male; Mice; Peroxidase; Trinitrobenzenesulfonic Acid | 2012 |
Intrarectal nitric oxide administration prevents cellular infiltration but not colonic injury during dextran sodium sulfate colitis.
During inflammation in the gastrointestinal tract, the production of nitric oxide (NO) is mediated by the mucosal conversion of L-arginine. Recently, it was shown that the gut microbiota can also produce NO.. The effect of gut luminal NO on inflammatory processes of an experimental colitis mice model was investigated by administrating NO directly to the colon, mimicking microbial NO production.. Twenty-four mice received daily intrarectal treatment with a NO donor in 2 doses and 8 mice were treated with placebo. Starting 1 day later, 18 of these mice were fed ad libitum with 4% of dextran sodium sulfate (DSS) in their drinking water to induce colitis. At day 6, histopathology (both the inflammation and damage score), myeloperoxidase (MPO)-activity, colon length and colonic permeability were evaluated.. Co-administration of NO during DSS exposure inhibited the induction of an increasing colonic MPO-activity. This protective effect of NO was confirmed by the histological inflammation score showing a similar trend. The colonic permeability was restored when very low levels of NO were administered to the DSS-mice. On the other hand, the colon length of the NO-treated DSS-mice was negatively correlated with the NO dose and the histological damage score was not improved.. Our results indicate that intrarectal administration of NO has clear anti-inflammatory effects in experimental colitis, but does not prevent colonic damage. Therefore, NO-producing microorganisms in the gut lumen should be accounted as a modulating process during colitis. Topics: Administration, Rectal; Animals; Cell Membrane Permeability; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Mice; Mice, Inbred Strains; Nitric Oxide; Peroxidase; Severity of Illness Index | 2012 |
Dextran sodium sulfate (DSS) induces colitis in mice by forming nano-lipocomplexes with medium-chain-length fatty acids in the colon.
Inflammatory bowel diseases (IBDs), primarily ulcerative colitis and Crohn's disease, are inflammatory disorders caused by multiple factors. Research on IBD has often used the dextran sodium sulfate (DSS)-induced colitis mouse model. DSS induces in vivo but not in vitro intestinal inflammation. In addition, no DSS-associated molecule (free glucose, sodium sulfate solution, free dextran) induces in vitro or in vivo intestinal inflammation. We find that DSS but not dextran associated molecules established linkages with medium-chain-length fatty acids (MCFAs), such as dodecanoate, that are present in the colonic lumen. DSS complexed to MCFAs forms nanometer-sized vesicles ~200 nm in diameter that can fuse with colonocyte membranes. The arrival of nanometer-sized DSS/MCFA vesicles in the cytoplasm may activate intestinal inflammatory signaling pathways. We also show that the inflammatory activity of DSS is mediated by the dextran moieties. The deleterious effect of DSS is localized principally in the distal colon, therefore it will be important to chemically modify DSS to develop materials beneficial to the colon without affecting colon-targeting specificity. Topics: Analysis of Variance; Animals; Colitis; Cytokines; Dextran Sulfate; Diet, High-Fat; DNA Primers; Electric Impedance; Endoscopy, Gastrointestinal; Fatty Acids; Female; Histological Techniques; Macromolecular Substances; Mice; Mice, Inbred C57BL; Nanostructures; Particle Size; Peroxidase; Transport Vesicles | 2012 |
Dietary intervention with green dwarf banana flour (Musa sp AAA) prevents intestinal inflammation in a trinitrobenzenesulfonic acid model of rat colitis.
Dietary products are among the therapeutic approaches used to modify intestinal microflora and to promote protective effects during the intestinal inflammatory process. Because the banana plant is rich in resistant starch, which is used by colonic microbiota for the anaerobic production of the short-chain fatty acids that serve as a major fuel source for colonocytes: first, green dwarf banana flour produces protective effects on the intestinal inflammation acting as a prebiotic and, second, combination of this dietary supplementation with prednisolone presents synergistic effects. For this, we used the trinitrobenzenesulphonic acid (TNBS) model of rat colitis. Our results revealed that the protective effect produced by a combination of 10% green dwarf banana flour with prednisolone was more pronounced than those promoted by a single administration of prednisolone or a diet containing 10% or 20% banana flour. This beneficial effect was associated with an improvement in the colonic oxidative status because the banana flour diet prevented the glutathione depletion and inhibited myeloperoxidase activity and lipid peroxidation. In addition, the intestinal anti-inflammatory activity was associated with an inhibition of alkaline phosphatase activity, a reduction in macroscopic and microscopic scores, and an extension of the lesions. In conclusion, the dietary use of the green dwarf banana flour constitutes an important dietary supplement and complementary medicine product to prevention and treatment of human inflammatory bowel disease. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Colitis; Colon; Dietary Supplements; Disease Models, Animal; Drug Synergism; Flour; Fruit; Glutathione; Inflammation; Lipid Peroxidation; Male; Musa; Oxidation-Reduction; Peroxidase; Phytotherapy; Plant Preparations; Prebiotics; Prednisolone; Rats, Wistar; Starch; Trinitrobenzenesulfonic Acid | 2012 |
Thymoquinone prevents and ameliorates dextran sulfate sodium-induced colitis in mice.
Thymoquinone (TQ), an active ingredient of the seed oil extract of Nigella sativa Linn, has previously been shown to possess antitumor, antioxidant, and anti-inflammatory bioactivity. Whether TQ has any effect on colitis remains controversial.. The aim of this study was to determine whether treatment with TQ prevents and ameliorates colonic inflammation in a mouse model of inflammatory bowel disease.. C57BL/6 murine colitis was induced by the administration of dextran sodium sulfate (DSS) (3 % W/V) in the drinking water supplied to the mice for 7 consecutive days. The mice with colitis were treated with 5, 10, or 25 mg/kg TQ orally, and changes in body weight and macroscopic and microscopic colitis scores were examined. In addition, biochemical analyses were conducted.. The treatment of mice with TQ prevented and significantly reduced the appearance of diarrhea and body weight loss. These results were associated with amelioration of colitis-related damage, as measured by macroscopic and microscopic colitis scores. In addition, there was a significant reduction in colonic myeloperoxidase activity and malondialdehyde levels and an increase in glutathione levels.. These results indicate that TQ administration can prevent and improve murine DSS-induced colitis. These findings suggest that TQ could serve as a potential therapeutic agent for the treatment of patients with inflammatory bowel disease. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzoquinones; Colitis; Dextran Sulfate; Female; Glutathione; Malondialdehyde; Mice; Mice, Inbred C57BL; Nigella sativa; Peroxidase; Plant Oils; Seeds; Time Factors | 2012 |
IL-33 attenuates development and perpetuation of chronic intestinal inflammation.
Interleukin-33 (IL-33) is a member of the IL-1 family. Recent evidence shows the importance of IL-33 in autoimmune and inflammatory diseases. To elucidate its impact on inflammatory bowel disease we studied the effects of exogenous IL-33 during the induction of acute dextran sodium sulfate (DSS)-induced colitis, the induction period of chronic DSS colitis, and after establishment of chronic inflammation.. For induction of acute colitis mice received DSS in their drinking water for 7 days and were killed at day 8 or 14 after first DSS administration. Chronic colitis was induced by four cycles of DSS. Animals were treated with IL-33 between the DSS cycles (intermediate treatment) or after onset of chronic disease (posttreatment). Colons and mesenteric lymph nodes were isolated for histology and cytokine secretion, flow cytometric analysis, determination of myeloperoxidase, and transcription factor activity.. While IL-33 in acute colitis led to slight aggravation of inflammation, both chronic colitis approaches resulted in a significant reduction of inflammatory colon contraction, amelioration of disease scores, suppression of interferon-gamma (IFN-γ), and a shift to T helper (Th)2-associated cytokines. Examination of colon tissue revealed increased Ly6g-mRNA levels and myeloperoxidase (MPO) activity in IL-33-treated animals. Evaluation of bacterial translocation revealed decreased translocation incidence in IL-33-treated mice.. In summary, IL-33 has extenuating effects in chronic DSS-induced colitis: Excessive Th1-directed cytokine responses are shifted toward Th2-like immune reactions and general inflammation parameters are reduced. IL-33-induced neutrophil influx during chronic inflammation reduced translocation of pathogenic bacteria across damaged epithelium. Topics: Acute Disease; Animals; Bacterial Translocation; Cell Movement; Chronic Disease; Colitis; Dextran Sulfate; Disease Models, Animal; Female; Flow Cytometry; Interferon-gamma; Interleukin-33; Interleukins; Liver; Lymph Nodes; Mice; Mice, Inbred BALB C; Neutrophils; Peroxidase; Recombinant Proteins; Spleen | 2012 |
Inhibitory effect of β-sitosterol on TNBS-induced colitis in mice.
β-Sitosterol, a common sterol in herbal medicines, exhibits anti-inflammatory effects beneficial in the treatment of lung inflammation, asthma, and bronchospasm. To evaluate whether β-sitosterol also has anticolitic benefits, we tested the effect of β-sitosterol on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. β-Sitosterol inhibited colon shortening and led to lowered macroscopic scores and myeloperoxidase activity in TNBS-treated colitic mice. β-Sitosterol also inhibited the expression of proinflammatory cytokines TNF-α, IL-1β, and IL-6, and an inflammatory enzyme, cyclooxygenase (COX)-2, in the colons of TNBS-induced colitic mice, as well as the activation of NF-κB. Based on these findings, β-sitosterol may ameliorate colitis by inhibiting the NF-κB pathway. Topics: Animals; Colitis; Cyclooxygenase 2; Interleukin-1beta; Interleukin-6; Male; Mice; Mice, Inbred C57BL; NF-kappa B; Peroxidase; Sitosterols; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2012 |
Preventative oral methylthioadenosine is anti-inflammatory and reduces DSS-induced colitis in mice.
Methylthioadenosine (MTA) is a precursor of the methionine salvage pathway and has been shown to have anti-inflammatory properties in various models of acute and chronic inflammation. However, the anti-inflammatory properties of MTA in models of intestinal inflammation are not defined. We hypothesized that orally administered MTA would be bioavailable and reduce morbidity associated with experimental colitis. We examined clinical, histological, and molecular markers of disease in mice provided oral MTA before (preventative) or after (therapy) the induction of colitis with 3% dextran sulfate sodium (DSS). We found a reduction in disease activity, weight loss, myeloperoxidase activity, and histological damage in mice given preventative MTA compared with DSS alone. We also found that equivalent supplementation with methionine could not reproduce the anti-inflammatory effects of MTA, and that MTA had no detectable adverse effects in control or DSS mice. Expression microarray analysis of colonic tissue showed several dominant pathways related to inflammatory cytokines/chemokines and extracellular matrix remodeling were upregulation by DSS and suppressed in MTA-supplemented mice. MTA is rapidly absorbed in the gastrointestinal tract and disseminated throughout the body, based on a time course analysis of an oral bolus of MTA. This effect is transient, with MTA levels falling to near baseline within 90 min in most organs. Moreover, MTA did not lead to increased blood or tissue methionine levels, suggesting that its effects are specific. However, MTA provided limited therapeutic benefit when administered after the onset of colitis. Our results show that oral MTA supplementation is a safe and effective strategy to prevent inflammation and tissue injury associated with DSS colitis in mice. Additional studies in chronic inflammatory models are necessary to determine if MTA is a safe and beneficial option for the maintenance of remission in human inflammatory bowel disease. Topics: Adenosine; Animals; Anti-Inflammatory Agents, Non-Steroidal; Biological Availability; Colitis; Dextran Sulfate; Diet; Gene Expression; Inflammation; Inflammatory Bowel Diseases; Male; Mice; Mice, Inbred C57BL; Microarray Analysis; Peroxidase; RNA, Messenger; Thionucleosides | 2012 |
Dietary intervention with narrow-leaved cattail rhizome flour (Typha angustifolia L.) prevents intestinal inflammation in the trinitrobenzenesulphonic acid model of rat colitis.
Inflammatory bowel disease (IBD) is a chronic inflammation of the intestinal epithelium that is driven by the intestinal immune system, oxidative stress and the loss of tolerance to the luminal microbiota. The use of dietary products containing ingredients such as fibres and carbohydrates and/or antioxidant compounds have been used as a therapeutic strategy for intestinal diseases because these products are considered effective in the modulation of the immune system and colonic microbiota. We investigated the beneficial effects of cattail rhizome flour (Typha angustifolia L.) in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis. In addition, we investigated the effects of cattail rhizome flour on the intestinal anti-inflammatory activity of prednisolone, which is a reference drug that is used for treatment of human IBD.. The present study included the preparation of flour from rhizomes of cattail (Typha angustifolia L.); an evaluation of the qualitative phytochemical profile of cattail rhizomes; an evaluation of the efficacy of cattail rhizome flour in TNBS-induced rat colitis; an evaluation of the synergistic effects of cattail rhizome flour on the intestinal anti-inflammatory activity of prednisolone; and macroscopic, clinical, biochemical, histopathological and microbiological studies to assess the healing effects of cattail rhizome flour and its synergistic effects in TNBS-induced rat colitis. The data were analysed by ANOVA, Kruskal-Wallis and χ(2) tests.. We tested several concentrations of cattail rhizome flour and found that dietary supplementation with 10% cattail rhizome flour showed the best effects at reducing the extension of the lesion, the colon weight ratio, adherences to adjacent organs and diarrhoea. These effects were related to inhibition of myeloperoxidase (MPO) and alkaline phosphatase (AP) activities and an attenuation of glutathione (GSH) depletion. The 10% cattail rhizome flour was as effective as prednisolone, and no synergistic effects were observed. Saponins, flavonoids and coumarins were detected in the rhizome flour. No changes were observed in the total number of lactic bacteria after dietary supplementation with cattail rhizome flour.. Dietary supplementation with 10% cattail rhizome flour and its combination with prednisolone prevent TNBS-induced colonic damage in rats, but no synergistic effects were observed. The prevention of TNBS-induced colon damage was associated with an improvement in intestinal oxidative stress, which likely resulted from the antioxidant properties of the active compounds detected in the cattail rhizome. This protective effect was not related to an improvement in lactic bacteria counts. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Colon; Diarrhea; Dietary Fiber; Dietary Supplements; Disease Models, Animal; Flour; Glutathione; Inflammation; Intestinal Mucosa; Male; Organ Size; Peroxidase; Phytotherapy; Plant Preparations; Prednisolone; Rats; Rats, Wistar; Rhizome; Trinitrobenzenesulfonic Acid; Typhaceae | 2012 |
Exogenous alkaline phosphatase treatment complements endogenous enzyme protection in colonic inflammation and reduces bacterial translocation in rats.
Alkaline phosphatase (AP) inactivates bacterial lipopolysaccharide and may therefore be protective. The small intestine and colon express intestinal (IAP) and tissue nonspecific enzyme (TNAP), respectively. The aim of this study was to assess the therapeutic potential of exogenous AP and its complementarity with endogenous enzyme protection in the intestine, as evidenced recently. IAP was given to rats by the oral or intrarectal route (700U/kgday). Oral budesonide (1mg/kgday) was used as a reference treatment. Treatment with intrarectal AP resulted in a 54.5% and 38.0% lower colonic weight and damage score, respectively, and an almost complete normalization of the expression of S100A8, LCN2 and IL-1β (p<0.05). Oral AP was less efficacious, while budesonide had a more pronounced effect on most parameters. Both oral and intrarectal AP counteracted bacterial translocation effectively (78 and 100%, respectively, p<0.05 for the latter), while budesonide failed to exert a positive effect. AP activity was increased in the feces of TNBS colitic animals, associated with augmented sensitivity to the inhibitor levamisole, suggesting enhanced luminal release of this enzyme. This was also observed in the mouse lymphocyte transfer model of chronic colitis. In a separate time course study, TNAP was shown to increase 2-3 days after colitis induction, while dextran sulfate sodium was a much weaker inducer of this isoform. We conclude that exogenous AP exerts beneficial effects on experimental colitis, which includes protection against bacterial translocation. AP of the tissue-nonspecific isoform is shed in higher amounts to the intestinal lumen in experimental colitis, possibly aiding in intestinal protection. Topics: Alkaline Phosphatase; Animals; Bacterial Translocation; Colitis; Dextran Sulfate; Disease Models, Animal; DNA, Bacterial; Feces; Female; Gene Expression Regulation, Enzymologic; Liver; Mice; Mice, Inbred C57BL; Mice, SCID; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2012 |
Dietary phosphatidylcholine supplementation attenuates inflammatory mucosal damage in a rat model of experimental colitis.
This study was designed to follow the time course of inflammatory activation in a rodent model of 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. We hypothesized that oral phosphatidylcholine (PC) pretreatment regimens may influence leukocyte-mediated microcirculatory reactions in this condition. In series I, Wistar rats were monitored 1 day after colitis induction (n = 24), and in series II (n = 24) on day 6 following a TNBS enema. The PC-pretreated animals received a 2% PC-enriched diet for 6 days before the TNBS enema (series I), or for 3 days before and 3 days after TNBS treatment (series II). The macrohemodynamics, serosal microcirculation (visualized by intravital videomicroscopy), colonic xanthine oxidoreductase, myeloperoxidase and nitric oxide end products, and changes in proinflammatory cytokine levels in plasma were measured. The mucosal structural injury was monitored in vivo by means of confocal laser scanning endomicroscopy. The TNBS enema induced a systemic hyperdynamic circulatory reaction with increased serosal capillary blood flow and significantly elevated colonic inflammatory enzyme activities, levels of nitric oxide production, and cytokine concentrations. Acute colitis caused disruption of the capillary network, whereas the morphologic damage was less severe in series II. The PC pretreatment protocols led to significant decreases in the serosal hyperemic reaction, the cytokine levels, and the inflammatory enzyme activities. The objective signs of tissue damage were reduced in both series, and the number of mucus-producing goblet cells in the resolving phase of colitis was increased. Dietary PC efficiently decreases the cytokine-mediated progression of inflammatory events and preserves the microvascular structure in the large intestine. Topics: Animals; Colitis; Colon; Dietary Supplements; Hemodynamics; Interleukin-6; Intestinal Mucosa; Male; Microcirculation; Nitric Oxide; Peroxidase; Phosphatidylcholines; Random Allocation; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Xanthine Dehydrogenase | 2012 |
Infliximab modifies mesenteric adipose tissue alterations and intestinal inflammation in rats with TNBS-induced colitis.
Infliximab is a monoclonal anti-TNF-α antibody that is used therapeutically to treat Crohn's disease (CD). High levels of pro-inflammatory cytokines, especially TNF-α, have been observed in the gastrointestinal tract of CD patients and were associated with alterations in the mesenteric adipose tissue, which also contributed to the high levels of adipokine release. The authors used a rat model of colitis that produces mesenteric adipose tissue alterations that are associated with intestinal inflammation to study the effects that infliximab treatment has on adipokine production, morphological alterations in adipose tissue and intestinal inflammation.. The ability of infliximab to neutralize rat TNF-α was evaluated in vitro using U937 cells. Colitis was induced by repeated intracolonic trinitrobenzene sulfonic acid instillations and was evaluated by macroscopic score, histopathological analysis, myeloperoxidase activity, TNF-α and IL-10 expression as well as iNOS (inducible NO synthase) expression and JNK phosphorylation in colon samples. The alterations in adipose tissue were assessed by TNF-α, IL-10, leptin, adiponectin and resistin levels as well as adipocyte size and peroxisome proliferator-activated receptor (PPAR)-γ expression.. Infliximab treatment controlled intestinal inflammation, which reduced lesions and neutrophil infiltration. Inflammatory markers, such as iNOS expression and JNK phosphorylation, were also reduced. In mesenteric adipose tissue, infliximab increased the production of IL-10 and resistin, which was associated with the restoration of adipocyte morphology and PPAR-γ expression.. Our results suggest that infliximab could contribute to the control of intestinal inflammation by modifying adipokine production by mesenteric adipose tissue. Topics: Adipose Tissue; Analysis of Variance; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antibodies, Monoclonal; Cell Survival; Colitis; Disease Models, Animal; Gene Expression; Humans; Infliximab; Interleukin-10; JNK Mitogen-Activated Protein Kinases; Male; Mesentery; Nitric Oxide Synthase Type II; Peroxidase; Phosphorylation; PPAR gamma; Rats; Rats, Wistar; Resistin; RNA, Messenger; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; U937 Cells | 2012 |
Dietary supplementation of an ellagic acid-enriched pomegranate extract attenuates chronic colonic inflammation in rats.
Dietary polyphenols present in Punica granatum (pomegranate), such as ellagitannins and ellagic acid (EA) have shown to exert anti-inflammatory and antioxidant properties. This study was designed to evaluate the effects of a dietary EA-enriched pomegranate extract (PE) in a murine chronic model of Cronh's disease (CD). Colonic injury was induced by intracolonic instillation of trinitrobenzensulfonic acid (TNBS). Rats were fed with different diets during 30 days before TNBS instillation and 2 weeks before killing: (i) standard, (ii) PE 250 mg/kg/day, (iii) PE 500 mg/kg/day, (iv) EA 10 mg/kg/day and (v) EA 10 mg/kg/day enriched-PE 250 mg/kg/day. Inflammation response was assessed by histology and MPO activity and TNF-α production. Besides, colonic expressions of iNOS, COX-2, p38, JNK, pERK1/2 MAPKs, IKBα and nuclear p65 NF-κB were studied by western blotting. MPO activity and the TNF-α levels were significantly reduced in dietary fed rats when compared with TNBS group. Similarly, PE and an EA-enriched PE diets drastically decreased COX-2 and iNOS overexpression, reduced MAPKs phosporylation and prevented the nuclear NF-κB translocation. Dietary supplementation of EA contributes in the beneficial effect of PE in this experimental colitis model and may be a novel therapeutic strategy to manage inflammatory bowel disease (IBD). Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Crohn Disease; Cyclooxygenase 2; Dietary Supplements; Disease Models, Animal; Ellagic Acid; I-kappa B Proteins; Interferon-alpha; Intestinal Mucosa; Lythraceae; Male; MAP Kinase Kinase 4; MAP Kinase Signaling System; NF-kappa B; NF-KappaB Inhibitor alpha; Nitric Oxide Synthase Type II; p38 Mitogen-Activated Protein Kinases; Peroxidase; Phosphorylation; Plant Extracts; Polyphenols; Rats; Rats, Wistar; Signal Transduction; Trinitrobenzenesulfonic Acid | 2012 |
Highly heated food rich in Maillard reaction products limit an experimental colitis in mice.
Maillard reaction products (MRPs) are a mixture of compounds generated after the heat treatment of food. High circulating levels of MRPs have been associated with degenerative pathologies such as diabetes, but little is known about their effect on the gut, the main organ in contact with food-derived MRPs. This study was aimed at determining whether repeated low-level exposure to MRPs, generated via two different heat treatments, can contribute to the modulation of experimental colitis in mice. In the first series of experiments, we tested whether pellets rich in MRPs would increase plasmatic and faecal concentration of MRPs. In the second series, we assessed whether two levels of pellet-derived MRPs would be able to modulate chemically-induced inflammation and affect tissue healing. The ingestion of MRPs correlates with the increase of its plasmatic and faecal concentration. Highly treated pellets were proved to significantly protect against inflammation whereas standard or moderately heated pellets had no effect on the inflammatory course. The chemical analysis of the different pellets indicated that high heating generates more melanoidins. There is a correlation between the exposure to highly heated foods and the reduction of murine inflammation, of which the mechanisms remain to be elucidated. Topics: Animals; Blood; Blood Chemical Analysis; Colitis; Colon; Disease Models, Animal; Feces; Food Handling; Hot Temperature; Inflammation; Maillard Reaction; Male; Mice; Peroxidase; Polymers | 2012 |
Proteome profiling of spinal cord and dorsal root ganglia in rats with trinitrobenzene sulfonic acid-induced colitis.
To investigate proteomic changes in spinal cord and dorsal root ganglia (DRG) of rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis.. The colonic myeloperoxidase (MPO) activity and tumor necrosis factor-α (TNF-α) level were determined. A two-dimensional electrophoresis (2-DE)-based proteomic technique was used to profile the global protein expression changes in the DRG and spinal cord of the rats with acute colitis induced by intra-colonic injection of TNBS.. TNBS group showed significantly elevated colonic MPO activity and increased TNF-α level. The proteins derived from lumbosacral enlargement of the spinal cord and DRG were resolved by 2-DE; and 26 and 19 proteins that displayed significantly different expression levels in the DRG and spinal cord were identified respectively. Altered proteins were found to be involved in a number of biological functions, such as inflammation/immunity, cell signaling, redox regulation, sulfate transport and cellular metabolism. The overexpression of the protein similar to potassium channel tetramerisation domain containing protein 12 (Kctd 12) and low expression of proteasome subunit α type-1 (psma) were validated by Western blotting analysis.. TNBS-induced colitis has a profound impact on protein profiling in the nervous system. This result helps understand the neurological pathogenesis of inflammatory bowel disease. Topics: Animals; Colitis; Colon; Ganglia, Spinal; Male; Peroxidase; Proteins; Proteome; Rats; Rats, Sprague-Dawley; Spinal Cord; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2012 |
The protective and healing effects of Si Shen Wan in trinitrobenzene sulphonic acid-induced colitis.
Si Shen Wan is a traditional Chinese herbal medicine formula for the treatment of diseases with diarrhea, such as ulcerative colitis, allergic colitis and chronic colitis. To investigate the protective and healing effects of Si Shen Wan in the experimental colitis induced by trinitrobenzene sulphonic acid, and to furture explore its mechanism of action.. Rats with colitis treated with Si Shen Wan for 10 days. Colon wet weight, colon organ coefficient, colonic damage score and pathological change after trinitrobenzene sulphonic acid challenge were determined. The levels of MPO, MDA, GSH-PX, SOD and the expression of IL-4 and IL-10 mRNA in the colon were also measured.. After treatment, colon wet weight, colon organ coefficient and colonic damage score were lower than that in the control group (p<0.05). MDA and MPO concentrations in the inflamed colonic tissues were decreased remarkably in the treated groups compared with that in the control group (p<0.05). But SOD level, IL-4 and IL-10 mRNA expression in the inflamed colonic tissues were obviously increased.. It is a potential path that protective effect of Si Shen Wan on impaired colonic mucosa rats with experimental colitis was accomplished by down-regulating the level of MDA and MPO, and up-regulating the level of SOD and the IL-4 and IL-10 mRNA expression in the colon mucosa. Topics: Animals; Colitis; Drugs, Chinese Herbal; Female; Glutathione Peroxidase; Interleukin-10; Interleukin-4; Intestinal Mucosa; Male; Malondialdehyde; Peroxidase; Phytotherapy; Protective Agents; Rats; Rats, Sprague-Dawley; RNA, Messenger; Superoxide Dismutase; Trinitrobenzenesulfonic Acid | 2012 |
An orally administered redox nanoparticle that accumulates in the colonic mucosa and reduces colitis in mice.
Drugs used to treat patients with ulcerative colitis are not always effective because of nonspecific distribution, metabolism in the gastrointestinal tract, and side effects. We designed a nitroxide radical-containing nanoparticle (RNP(O)) that accumulates specifically in the colon to suppress inflammation and reduce the undesirable side effects of nitroxide radicals.. RNP(O) was synthesized by assembly of an amphiphilic block copolymer that contains stable nitroxide radicals in an ether-linked hydrophobic side chain. Biodistribution of RNP(O) in mice was determined from radioisotope and electron spin resonance measurements. The effects of RNP(O) were determined in mice with dextran sodium sulfate (DSS)-induced colitis and compared with those of low-molecular-weight drugs (4-hydroxyl-2,2,6,6-tetramethylpiperidine-1-oxyl [TEMPOL] or mesalamine).. RNP(O), with a diameter of 40 nm and a shell of poly(ethylene glycol), had a significantly greater level of accumulation in the colonic mucosa than low-molecular-weight TEMPOL or polystyrene latex particles. RNP(O) was not absorbed into the bloodstream through the intestinal wall, despite its long-term retention in the colon, which prevented its distribution to other parts of the body. Mice with DSS-induced colitis had significantly lower disease activity index and less inflammation following 7 days of oral administration of RNP(O) compared with mice with DSS-induced colitis or mice given low-molecular-weight TEMPOL or mesalamine.. We designed an orally administered RNP(O) that accumulates specifically in the colons of mice with colitis and is more effective in reducing inflammation than low-molecular-weight TEMPOL or mesalamine. RNP(O) might be developed for treatment of patients with ulcerative colitis. Topics: Analysis of Variance; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Colitis; Colon; Cyclic N-Oxides; Dextran Sulfate; Interleukin-1beta; Intestinal Mucosa; Male; Mesalamine; Mice; Mice, Inbred ICR; Nanoparticles; Nitrogen Oxides; Peroxidase; Reactive Oxygen Species; Severity of Illness Index; Spin Labels; Superoxides; Survival Rate | 2012 |
N-methyl-D-aspartate receptor antagonist therapy suppresses colon motility and inflammatory activation six days after the onset of experimental colitis in rats.
We set out to investigate the time-dependent colon motility and inflammatory changes in a rodent model of 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in order to estimate the efficacy of N-methyl-D-aspartate (NMDA) receptor antagonist therapy administered 6 day after the acute inflammatory event. Anaesthetized Sprague-Dawley rats were randomized to control (n=6) or colitis groups (n=18). The endogenous NMDA receptor antagonist kynurenic acid (n=6) or the synthetic analog SZR-72 (n=6) was administered 6 day after TNBS induction. Large bowel motility parameters, macrohaemodynamics and serosal microcirculatory changes were recorded; the severity of colonic damage was monitored by using in vivo confocal laser endomicroscopy. Nitrite/nitrate and nitrotyrosine levels, and xanthine oxidoreductase and myeloperoxidase activities were determined on colon biopsies; plasma levels of TNF-α and IL-6 were compared with those under control and 1-day colitis (n=6) conditions. TNBS induction elevated the tissue inflammatory enzyme activities, proinflammatory cytokine release, and nitrite/nitrate and nitrotyrosine formation. The microscopic vascular and mucosal lesions were accompanied by significant increases in serosal microcirculation and frequent intestinal movements 6 day after colitis. The NMDA receptor antagonist treatments significantly decreased the signs of inflammatory activation and the levels of nitric oxide end-products, normalized the microcirculation and the rate of bowel movements in both NMDA receptor antagonist-treated colitis groups. Blockade of the enteric NMDA receptors 6 day after colitis induction concurrently influenced NO production-linked nitrosative stress and colon dysmotility and may therefore offer a possibility via which to inhibit the progression of inflammatory changes in the later phase of TNBS colitis. Topics: Animals; Colitis; Colon; Disease Models, Animal; Gastrointestinal Motility; Hemodynamics; Interleukin-6; Kynurenic Acid; Male; Microcirculation; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, N-Methyl-D-Aspartate; Time Factors; Tumor Necrosis Factor-alpha; Tyrosine; Xanthine Dehydrogenase | 2012 |
Orally administered aqueous extract of Inonotus obliquus ameliorates acute inflammation in dextran sulfate sodium (DSS)-induced colitis in mice.
Chaga mushroom (Inonotus obliquus) has been used in folk medicine to treat several disorders through its various biological functions. I. obliquus is claimed to produce general immune-potentiating and strengthening, antiinflammatory, and antitumor properties, but its effects on intestinal inflammation (ulcerative colitis) are clearly not understood.. To determine the effects and mode of action of an aqueous extract of I. obliquus (IOAE) on experimental colitis in mice induced by dextran sulfate sodium (DSS).. Female 5-week-C57BL/6 mice were randomized into groups differing in treatment conditions (prevention and treatment) and doses of IOAE (50 and 100mg/kg body weight). Mice were exposed to DSS (2%) in their drinking water over 7 day to induce acute intestinal inflammation. In colon tissues, we evaluated histological changes by hematoxylin and eosin staining, levels of iNOS by immuno-histochemical staining, and neutrophil influx by myeloperoxidase assay. mRNA expression of pro-inflammatory mediators TNF-α, IL-1β, IL-6, and IFN-γ was determined by RT-PCR.. Histological examinations indicated that IOAE suppressed edema, mucosal damage, and the loss of crypts induced by DSS. IOAE markedly attenuated DSS-induced iNOS levels and myeloperoxidase accumulation in colon tissues, demonstrating its suppressive effect on infiltration of immune cells. In addition, IOAE significantly inhibited mRNA expression of pro-inflammatory cytokines induced by DSS in colon tissues.. Our results suggest anti-inflammatory effect of IOAE at colorectal sites due to down-regulation of the expression of inflammatory mediators. Suppression of TNF-α and iNOS together with IL-1β by IOAE denotes that it might be a useful supplement in the setting of inflammatory bowel disease. Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Basidiomycota; Colitis; Complex Mixtures; Cytokines; Dextran Sulfate; Female; Fungal Proteins; Mice; Mice, Inbred C57BL; Nitric Oxide Synthase Type II; Peroxidase; Phenols; Polysaccharides; RNA, Messenger | 2012 |
The PepT1-transportable soy tripeptide VPY reduces intestinal inflammation.
Inflammatory bowel disease (IBD) is a chronic inflammation of the gastrointestinal tract. The peptide transporter PepT1 is responsible for the intestinal uptake of dietary peptides, and its expression in the gastrointestinal tract is up-regulated during intestinal inflammation, indicating that PepT1 may be a promising target for IBD therapeutics.. The transport of soy-derived di- and tripeptides across Caco-2 intestinal epithelial cells was examined, and the anti-inflammatory effects of the transported peptide VPY were evaluated in vitro in Caco-2 and THP-1 macrophages, and in vivo in a mouse model of DSS-induced colitis.. VPY inhibited the secretion of IL-8 and TNF-α, respectively, from Caco-2 and THP-1 cells. VPY transport and anti-inflammatory activity in Caco-2 cells was reduced in the presence of Gly-Sar, indicating this activity was mediated by PepT1. In mice, VPY treatment reduced DSS-induced colitis symptoms and weight loss, improved colon histology, reduced MPO activity, and decreased gene expression of the pro-inflammatory cytokines TNF-α, IL-6, IL-1β, IFN-γ and IL-17 in the colon.. VPY is a novel PepT1 substrate that can inhibit the production of pro-inflammatory mediators in vitro in intestinal epithelial and immune cells, and reduce the severity of colitis in mice by down-regulating the expression of pro-inflammatory cytokines in the colon, suggesting that VPY may be promising for the treatment of IBD. Topics: Animals; Anti-Inflammatory Agents; Caco-2 Cells; Colitis; Cytokines; Humans; Interleukin-6; Mice; Oligopeptides; Peptide Transporter 1; Peroxidase; Soybean Proteins; Symporters; Tumor Necrosis Factor-alpha | 2012 |
MC-12, an annexin A1-based peptide, is effective in the treatment of experimental colitis.
Annexin A1 (ANXA1) inhibits NF-κB, a key regulator of inflammation, the common pathophysiological mechanism of inflammatory bowel diseases (IBD). MC-12, an ANXA1-based tripeptide, suppresses NF-κB activation. Here, we determined the efficacy of MC-12 in the control of IBD. Mice with colitis induced by dextran sodium sulfate (DSS) or 2,4,6-trinitro benzene sulfonic acid (TNBS) were treated with various doses of MC-12 administered intraperitoneally, orally or intrarectally. We determined colon length and the histological score of colitis, and assayed: in colon tissue the levels of TNF-α, IFN-γ, IL-1β, IL-6 and IL-10 by RT-PCR; prostaglandin E(2) (PGE(2)), cytoplasmic phospholipase A(2) (cPLA(2)) and myeloperoxidase by immunoassay; and COX-2 and NF- κB by immunohistochemistry; and in serum the levels of various cytokines by immunoassay. In both models MC-12: reversed dose-dependently colonic inflammation; inhibited by up to 47% myeloperoxidase activity; had a minimal effect on cytoplasmic phospholipase A(2); reduced significantly the induced levels of TNF-α, IFN-γ, IL-1β, IL-6 and IL-10, returning them to baseline. DSS and TNBS markedly activated NF-κB in colonic epithelial cells and MC-12 decreased this effect by 85.8% and 72.5%, respectively. MC-12 had a similar effect in cultured NCM460 normal colon epithelial cells. Finally, MC-12 suppressed the induction of COX-2 expression, the level of PGE(2) in the colon and PGE(2) metabolite in serum. In conclusion, MC-12, representing a novel class of short peptide inhibitors of NF-κB, has a strong effect against colitis in two preclinical models recapitulating features of human IBD. Its mechanism of action is complex and includes pronounced inhibition of NF-κB. MC-12 merits further development as an agent for the control of IBD. Topics: Animals; Annexin A1; Cell Line; Colitis; Colon; Cyclooxygenase 2; Cytokines; Dextran Sulfate; Dinoprostone; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Induction; Female; Group IV Phospholipases A2; Humans; Intestinal Mucosa; Mice; NF-kappa B; Oligopeptides; Peroxidase; Trinitrobenzenesulfonic Acid | 2012 |
Heligmosmoides polygyrus fourth stages induce protection against DSS-induced colitis and change opioid expression in the intestine.
Primary exposure of mice to the nematode Heligmosomoides polygyrus infection reduces inflammation in an experimental model of colitis. The aim of the present investigation was to evaluate whether the reduced inflammation provoked by H. polygyrus L4 larvae in BALB/c mice treated with dextran sulphate sodium is associated with changed expression of opioids in the small intestine and colon. Colitis was induced by 5% Dextran sulphate sodium (DSS) oral administration for 3 days before oral infection with 200 infective larvae (L3) H. polygyrus until the end of the experiment, 6 days post-infection. Clinical disease symptoms were monitored daily. The expressions of proopiomelanocortin POMC1, MOR1 (Oprm1) - opioid receptor and β-endorphin were determined by RT-PCR, Western blot and immunoassay, respectively, in the colon and small intestine of mice. RT-PCR analysis of colon tissues showed up-regulation of the expression of POMC and MOR1 opioid-dependent genes in mice with DSS-induced colitis. H. polygyrus L4 larvae inhibited DSS-induced colitis symptoms that were correlated with increased IL-1β, TNF-α, IL-6, myeloperoxidase (MPO) concentration, macrophages infiltration and MOR1, POMC and β-endorphin increased expression in the small intestine and inhibition of those in the colon. Topics: Animals; beta-Endorphin; Blotting, Western; Colitis; Cytokines; Dextran Sulfate; Gene Expression Profiling; Intestines; Larva; Macrophages; Male; Mice; Mice, Inbred BALB C; Nematospiroides dubius; Neutrophils; Peroxidase; Pro-Opiomelanocortin; Real-Time Polymerase Chain Reaction; Receptors, Opioid; Severity of Illness Index | 2012 |
Inhibition of CXCR2 profoundly suppresses inflammation-driven and spontaneous tumorigenesis.
The chemokine receptor CXCR2 is a key mediator of neutrophil migration that also plays a role in tumor development. However, CXCR2 influences tumors through multiple mechanisms and might promote or inhibit tumor development depending on context. Here, we used several mouse models of spontaneous and inflammation-driven neoplasia to define indispensable roles for CXCR2 in benign and malignant tumors. CXCR2-activating chemokines were part of the secretome of cultured primary benign intestinal adenomas (ApcMin/+) and highly expressed by all tumors in all models. CXCR2 deficiency profoundly suppressed inflammation-driven tumorigenesis in skin and intestine as well as spontaneous adenocarcinoma formation in a model of invasive intestinal adenocarcinoma (AhCreER;Apcfl/+;Ptenfl/fl mice). Pepducin-mediated CXCR2 inhibition reduced tumorigenesis in ApcMin/+ mice. Ly6G+ neutrophils were the dominant source of CXCR2 in blood, and CXCR2 deficiency attenuated neutrophil recruitment. Moreover, systemic Ly6G+ cell depletion purged CXCR2-dependent tumor-associated leukocytes, suppressed established skin tumor growth and colitis-associated tumorigenesis, and reduced ApcMin/+ adenoma formation. CXCR2 is thus a potent protumorigenic chemokine receptor that directs recruitment of tumor-promoting leukocytes into tissues during tumor-inducing and tumor-driven inflammation. Similar leukocyte populations were also found in human intestinal adenomas, which suggests that CXCR2 antagonists may have therapeutic and prophylactic potential in the treatment of cancer. Topics: 9,10-Dimethyl-1,2-benzanthracene; Adenocarcinoma; Adenoma; Animals; Animals, Inbred Strains; Azoxymethane; Cell Transformation, Neoplastic; Chemokines, CXC; Colitis; Colonic Neoplasms; Dermatitis, Contact; Dextran Sulfate; Gene Expression; Mice; Mice, 129 Strain; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; Papilloma; Peroxidase; Precancerous Conditions; Receptors, Interleukin-8B; Skin Neoplasms; Statistics, Nonparametric; Tetradecanoylphorbol Acetate; Tumor Burden | 2012 |
[Comparative study of novel therapeutic possibilities in animal experimental model of inflammatory bowel disease].
The consequence of inflammatory bowel diseases (IBD) is cytokine-mediated severe local tissue damage. Our aim was to determine the extent of inflammatory response and to influence the morphologic changes during the subacute phase of trinitro-benzene sulfonic acid (TNBS)-induced experimental colitis by oral phosphatidylcholine (PC) and N-methyl-D-aspartate (NMDA) receptor antagonist kynurenic acid therapy.. Sprague-Dawley rats were randomized to control, untreated colitis (ic TNBS), colitis fed with 2% PC-containing diet (3 days pre-treatment +3 days treatment after TNBS induction), colitis with kynurenic acid treatment (on day 6, n = 7) groups. The colitis was characterized by tissue myeloperoxidase and plasma TNF-alpha levels, the extent of tissue damage, structural changes in microvasculature (FITC-dextran staining) and mucosal injury (acridine orange staining) were determined by in vivo confocal laser scanning endomicroscopy (Optiscan Five1, Australia) and conventional histology (hematoxyilin-eosin staining).. Significant elevation in myeloperoxidase and TNF-alpha levels with remarkable damage in epithelial structure was detected in the colitis group. Both treatment regimens significantly decreased the level of inflammatory activation but only PC pretreatment could preserve the number of goblet cells and the epithelial structure. Treatment with kynurenic acid did not alter the morphology changes.. Oral PC pretreatment is a promising possibility in the therapy of IBDs through decreasing inflammatory reaction and increasing the number of goblet cells. Topics: Administration, Oral; Animals; Biomarkers; Colitis; Disease Models, Animal; Excitatory Amino Acid Antagonists; Inflammation; Inflammatory Bowel Diseases; Intestinal Mucosa; Kynurenic Acid; Microcirculation; Microscopy, Confocal; Peroxidase; Phosphatidylcholines; Random Allocation; Rats; Rats, Sprague-Dawley; Receptors, N-Methyl-D-Aspartate; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2012 |
The antiprotozoal drug pentamidine ameliorates experimentally induced acute colitis in mice.
Intestinal inflammation is partly driven by enteroglial-derived S100B protein. The antiprotozoal drug pentamidine directly blocks S100B activity. We aimed to investigate the effect of pentamidine on intestinal inflammation using an animal model of dextran sodium sulphate (DSS)-induced acute colitis.. Mice were divided into: control group, colitis group (4% DSS for four days) and two pentamidine-treated colitis groups (0.8 mg/kg and 4 mg/kg). Anti-inflammatory effect of pentamidine was assessed in colonic tissue by evaluating the disease activity index and the severity of histological changes. Colonic tissue were also used to evaluate cyclooxigenase-2, inducible nitric oxide synthase, S100B, glial fibrillary acidic protein, phosphorylated-p38 MAPkinase, p50, p65 protein expression, malondyaldheyde production, mieloperoxidase activity, and macrophage infiltration. Nitric oxide, prostaglandin E2, interleukin-1 beta, tumor necrosis factor alpha, and S100B levels were detected in plasma samples. Parallel measurements were performed in vitro on dissected mucosa and longitudinal muscle myenteric plexus (LMMP) preparations after challenge with LPS + DSS or exogenous S100B protein in the presence or absence of pentamidine.. Pentamidine treatment significantly ameliorated the severity of acute colitis in mice, as showed by macroscopic evaluation and histological/biochemical assays in colonic tissues and in plasma. Pentamidine effect on inflammatory mediators was almost completely abrogated in dissected mucosa but not in LMMP.. Pentamidine exerts a marked anti-inflammatory effect in a mice model of acute colitis, likely targeting S100B activity. Pentamidine might be an innovative molecule to broaden pharmacological tools against colitis. Topics: Animals; Antiprotozoal Agents; Colitis; Colon; Cyclooxygenase 2; Dextran Sulfate; Dinoprostone; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Gene Expression Regulation; Interleukin-1beta; Macrophages; Male; Mice; Mucous Membrane; Nerve Tissue Proteins; Neutrophil Infiltration; Nitrites; Pentamidine; Peroxidase; Severity of Illness Index; Time Factors; Tumor Necrosis Factor-alpha; Tumor Suppressor Protein p53 | 2012 |
Suppression of dextran sulfate sodium-induced colitis in mice by radon inhalation.
The enhanced release of reactive oxygen species from activated neutrophils plays important role in the pathogenesis of inflammatory bowel disease. We previously reported that radon inhalation activates antioxidative functions in various organs of mice. In this study, we examined the protective effects of radon inhalation on dextran sulfate sodium- (DSS) induced colitis in mice which were subjected to DSS for 7 days. Mice were continuously treated with air only (sham) or radon at a concentration of 2000 Bq/m³ from a day before DSS administration to the end of colitis induction. In the results, radon inhalation suppressed the elevation of the disease activity index score and histological damage score induced by DSS. Based on the changes in tumor necrosis factor-alpha in plasma and myeloperoxidase activity in the colon, it was shown that radon inhalation suppressed DSS-induced colonic inflammation. Moreover, radon inhalation suppressed lipid peroxidation of the colon induced by DSS. The antioxidant level (superoxide dismutase and total glutathione) in the colon after DSS administration was significantly higher in mice treated with radon than with the sham. These results suggested that radon inhalation suppressed DSS-induced colitis through the enhancement of antioxidative functions in the colon. Topics: Administration, Inhalation; Animals; Colitis; Dextran Sulfate; Inflammatory Bowel Diseases; Male; Mice; Mice, Inbred BALB C; Peroxidase; Radon; Reactive Oxygen Species | 2012 |
Lactobacillus plantarum prevents the development of colitis in IL-10-deficient mouse by reducing the intestinal permeability.
It is reported that defects exist in the small intestinal epithelial barrier of inflammatory bowel disease, which might be associated with increased intestinal permeability at a very early stage. Our study aims to investigate the role of Lactobacillus plantarum on the decrease of epithelial permeability and the further protective effects on the intestinal epithelial barrier using the IL-10-deficient mouse model. Our study showed that tight junction associated proteins were increased after the pre-treatment of L. plantarum by fluorescence staining, western blot, real-time PCR and transmission electron microscope. Oral gavage of milk containing L. plantarum was effective in decreasing small intestinal permeability using methods of Ussing chamber assay and sugar probe. Assay of pro-inflammatory cytokines IFN-γ, TNF-α, MPO, and colonic histology by ELISA showed protective effects of L. plantarum on the intestinal epithelial barrier. Therefore, L. plantarum may prevent the development of colitis in IL-10-deficient mice by blocking changes in the expression of TJ proteins, TJ structure and intestinal permeability. Topics: Animals; Colitis; Cytokines; Inflammation; Interleukin-10; Intestinal Mucosa; Intestines; Lactobacillus plantarum; Mice; Mice, Transgenic; Milk; Permeability; Peroxidase; Tight Junctions | 2011 |
Intestinal alkaline phosphatase has beneficial effects in mouse models of chronic colitis.
The brush border enzyme intestinal alkaline phosphatase (IAP) functions as a gut mucosal defense factor and is protective against dextran sulfate sodium (DSS)-induced acute injury in rats. The present study evaluated the potential therapeutic role for orally administered calf IAP (cIAP) in two independent mouse models of chronic colitis: 1) DSS-induced chronic colitis, and 2) chronic spontaneous colitis in Wiskott-Aldrich Syndrome protein (WASP)-deficient (knockout) mice that is accelerated by irradiation.. The wildtype (WT) and IAP knockout (IAP-KO) mice received four cycles of 2% DSS ad libitum for 7 days. Each cycle was followed by a 7-day DSS-free interval during which mice received either cIAP or vehicle in the drinking water. The WASP-KO mice received either vehicle or cIAP for 6 weeks beginning on the day of irradiation.. Microscopic colitis scores of DSS-treated IAP-KO mice were higher than DSS-treated WT mice (52±3.8 versus 28.8±6.6, respectively, P<0.0001). cIAP treatment attenuated the disease in both groups (KO=30.7±6.01, WT=18.7±5.0, P<0.05). In irradiated WASP-KO mice cIAP also attenuated colitis compared to control groups (3.3±0.52 versus 6.2±0.34, respectively, P<0.001). Tissue myeloperoxidase activity and proinflammatory cytokines were significantly decreased by cIAP treatment.. Endogenous IAP appears to play a role in protecting the host against chronic colitis. Orally administered cIAP exerts a protective effect in two independent mouse models of chronic colitis and may represent a novel therapy for human IBD. Topics: Alkaline Phosphatase; Animals; Chronic Disease; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Intestinal Mucosa; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Wiskott-Aldrich Syndrome; Wiskott-Aldrich Syndrome Protein | 2011 |
Is Crohn's creeping fat an adipose tissue?
In human pathology, the "creeping fat" (CF) of the mesentery is unique to Crohn's disease (CD). CF is usually referred to as an ectopic extension of mesenteric adipose tissue (MAT). However, since no animal model developing CF has ever been established, very little is known about this type of fat-depot expansion and its role in the development of the disease.. We developed and standardized an experimental protocol in mice that reproducibly induces CF development when a severe colonic inflammation is obtained by intracolonic instillation of DNBS.. Macro-microscopic observations revealed a fatty appearance of CF. Yet when compared to MAT from the same animals, CF contains very little triglycerides, few adipocytes, and we observed a very low expression and protein levels of both adipose markers (hormone-sensitive lipase, perilipin) and adipocytokines (leptin, adiponectin). The decreased expression of perilipin in CF was also observed by immunohistochemistry. Conversely, the expression of proinflammatory and fibrous markers (Pref-1) was much higher in CF than in MAT. These observations were fully consistent with those made on CF recovered from five CD patients and compared with subcutaneous and mesenteric fat from the same patients.. Altogether, this work reports an original experimental mice model of CF. In this model we establish for the first time that CF only occurs in severe colonic inflammation and shows an inflammatory, fibrous but not an adipose pattern. Topics: Adipose Tissue; Animals; Blotting, Western; Body Weight; Colitis; Crohn Disease; Dinitrofluorobenzene; Enzyme-Linked Immunosorbent Assay; Humans; Immunoenzyme Techniques; Lipids; Male; Mesentery; Mice; Mice, Inbred BALB C; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger | 2011 |
Arsenic trioxide reduces 2,4,6-trinitrobenzene sulfonic acid-induced murine colitis via nuclear factor-κB down-regulation and caspase-3 activation.
Arsenic trioxide, As(2)O(3), already used in human anti-cancer therapy, is also an efficient agent against the autoimmune and inflammatory diseases developed in MRL/lpr mice. Inflammatory bowel diseases (IBDs), notably Crohn's disease, which remain without efficient treatment, display autoimmune and inflammatory components. We, therefore, hypothesized that As(2)O( 3) may be active on IBDs. Using the 2,4,6-trinitrobenzene sulfonic acid-induced murine model of colitis, we demonstrate that As(2)O(3) used either in a preventive or a curative mode markedly reduced the induced colitis as assessed by macroscopic and microscopic scores, leading to prolonged mice survival. In addition, As(2)O(3) was able to inhibit NF-κB expression and DNA-binding in colon extracts leading to decreased cytokine gene expression (i.e. tumor necrosis factor-α, interleukin(IL)-1β, IL-12, IL-17, IL-18, and IL-23). Interestingly, As(2)O(3) also reduced keratinocyte-derived chemokine (KC), inducible nitric oxide synthase (iNOS) mRNA levels, and myeloperoxidase (MPO) protein expression suggesting an impairment of neutrophils. This was associated with a marked increase of procaspase-3 and induced caspase-3 activation. This caspase-3 co-localized with MPO in the remaining neutrophils suggesting that As(2)O( 3) might have eliminated inflamed cells probably by inducing their apoptosis. These results assessed the potent anti-inflammatory effect of As(2)O( 3), that targets both NF-κB and caspase-3 pathways, and suggests a therapeutic potential for Crohn's disease and other severe IBDs. Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Arsenic Trioxide; Arsenicals; Caspase 3; Colitis; Colon; Crohn Disease; Cytokines; Disease Models, Animal; Humans; Male; Mice; Mice, Inbred BALB C; NF-kappa B; Nitric Oxide Synthase Type II; Oxides; Peroxidase; Trinitrobenzenesulfonic Acid | 2011 |
Dietary heme adversely affects experimental colitis in rats, despite heat-shock protein induction.
Research on dietary modulation of inflammatory bowel disease is in its infancy. Dietary heme, mimicking red meat, is cytotoxic to colonic epithelium and thus may aggravate colitis. Alternatively, heme-induced colonic stress might also result in potential protective heat-shock proteins (HSPs). Therefore, we investigated the effect of dietary heme on trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats.. Rats were fed a high-fat control diet or a similar diet supplemented with heme. After dietary adaptation, rats were rectally infused with TNBS for colitis induction or saline for sham treatment. Colitis severity was evaluated and several markers were quantified in colonic mucosa isolated 1 wk after colitis induction. Furthermore, cytotoxicity of fecal water and serum α-1-acid glycoprotein were measured.. Dietary heme increased cytotoxicity of the fecal water. Heme-fed sham-treated rats had higher colonic HSP-25 and heme-oxygenase-1 mRNA levels, which was confirmed by immunohistochemistry. HSP induction by heme was associated with decreased protein levels of myeloperoxidase and interleukin-1β after subsequent TNBS infusion. However, no dietary effects were observed on histologic colitis score. Furthermore, body weight gain, colon length, and food intake were lower and α-1-acid glycoprotein concentrations were higher in heme-fed colitic rats. In addition, somatostatin, involved in mucosal repair, was not changed with TNBS infusion in heme-fed rats.. Dietary heme adversely affects colitis, despite HSP induction. We speculate that the irritating influence of dietary heme, being continuously present in the colon, impairs recovery after colitis induction. A diet high in red meat might be a risk factor for inflammatory bowel disease development. Topics: Animals; Biomarkers; Colitis; Colon; Enterobacter; Heat-Shock Proteins; Heme; Heme Oxygenase-1; Inflammation; Interleukin-1beta; Intestinal Mucosa; Lactobacillaceae; Male; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2011 |
Oral administration of docosahexaenoic acid attenuates colitis induced by dextran sulfate sodium in mice.
Dietary supplementation of n-3 PUFAs, containing docosahexaenoic acid (DHA), modulates the symptoms of colitis. Hence, we investigated the effects of oral administration of pure DHA and the therapeutic agent sulfasalazine (SAL) on chemically induced colitis in mice, and analyzed the expression levels of DHA-responsive genes in colonic tissue using cDNA arrays.. Colitis in BALB/c mice was induced by feeding 5% dextran sulfate sodium (DSS) in drinking water for 7 days. DHA (30 mg/kg/day, DHA) or SAL (100 mg/kg/day, SAL) was administered orally throughout the treatment along with DSS. The DHA-treated group showed significant reduction of the weight loss and colon shortening compared to the DSS-treated colitis group. In contrast, SAL treatment was effective in reducing colon shortening, stool consistency and bleeding scores. DHA and SAL treatments also significantly reduced the changes in inflammation of the colon, and reversed the increase in myeloperoxidase activity induced by DSS. Among DSS-responsive genes, those for inflammatory cytokines (IL-1β, CD14 antigen and tumor necrosis factor receptor superfamily, member 1b), membrane remodeling genes (matrix metalloproteinase-3, -10 and -13) and acute phase proteins (S100 calcium-binding protein A8), which were increased by DSS, were downregulated by DHA or SAL treatment.. DHA was effective in alleviating DSS-induced colitis in mice, partly by modulating the expression levels of genes involved in colitis. Topics: Acute-Phase Proteins; Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Body Weight; Colitis; Colon; Dextran Sulfate; Docosahexaenoic Acids; Gene Expression Regulation; Inflammation Mediators; Intestinal Mucosa; Irritants; Male; Mice; Mice, Inbred BALB C; Oligonucleotide Array Sequence Analysis; Peroxidase; Random Allocation; RNA, Messenger; Severity of Illness Index; Sulfasalazine | 2011 |
Rho kinase signalling mediates radiation-induced inflammation and intestinal barrier dysfunction.
Radiotherapy is important in the management of pelvic malignancies, but radiation-induced intestinal damage is a dose-limiting factor. Microvascular injury and epithelial barrier dysfunction are considered to be rate-limiting aspects in radiation-induced enteropathy. This study investigated the role of Rho kinase signalling in radiation-induced inflammation and intestinal barrier dysfunction.. The specific Rho kinase inhibitor Y-27632 (1 and 10 mg/kg) was given to C57BL/6J mice before challenge with 20 Gy radiation. Leucocyte- and platelet-endothelium interactions in the colonic microcirculation were assessed by intravital microscopy. Levels of myeloperoxidase (MPO) and CXC chemokines (macrophage inflammatory protein 2 and cytokine-induced neutrophil chemoattractant), and intestinal leakage were quantified after 16 h.. Radiation increased leucocyte and platelet recruitment, MPO activity, CXC chemokine production and intestinal leakage. Y-27632 significantly reduced radiation-induced leucocyte rolling and abolished adhesion; it also decreased platelet rolling and adhesion by 55 and 74 per cent respectively (P < 0·050). Inhibition of Rho kinase signalling significantly decreased radiation-provoked formation of CXC chemokines, MPO activity by 52 per cent, and intestinal leakage by 67 per cent (P < 0·050).. Rho kinase activity constitutes an important signalling mechanism in radiation-induced inflammation and intestinal barrier dysfunction. Topics: Amides; Animals; Biomarkers; Chemokines; Colitis; Colon; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Leukocytes; Male; Mice; Mice, Inbred C57BL; Permeability; Peroxidase; Platelet Activation; Pyridines; Radiation Injuries, Experimental; rho-Associated Kinases; Signal Transduction | 2011 |
DNA vaccination targeting macrophage migration inhibitory factor prevents murine experimental colitis.
Previous studies have shown that neutralization of macrophage migration inhibitory factor (MIF) by anti-MIF antibody reduces intestinal inflammation in mice. In this study we tested whether or not anti-MIF autoantibody induced by DNA vaccine targeting MIF protects mice against experimental colitis. Mice were administered a MIF-deoxyribonucleic acid (DNA) vaccine by introducing oligonucleotides encoding helper T epitope into the cDNA sequence of murine MIF by in vivo electroporation. Preventive effects of this method against dextran sulphate sodium-induced (DSS) colitis were evaluated. Mice administered with MIF-DNA vaccine raised values of autoantibody significantly. The clinical and histological findings of colitis induced by 3·0% DSS solution were ameliorated significantly in mice treated with MIF-DNA vaccine compared with saline or pCAGGS-treated mice given DSS. Myeloperoxidase activity, infiltration of F4/80-positive staining cells and the levels of proinflammatory cytokines were suppressed in the colon of MIF-DNA vaccine treated mice compared with saline or pCAGGS-treated mice exposed to DSS. Our results suggest that immunization with helper T epitope DNA-vaccine targeting MIF may be a useful approach for the treatment of colitis including inflammatory bowel diseases. Topics: Animals; Antigens, Differentiation; Autoantibodies; Colitis; Cytokines; Dextran Sulfate; Macrophage Migration-Inhibitory Factors; Male; Mice; Mice, Inbred BALB C; Peroxidase; Vaccines, DNA | 2011 |
Anti-inflammatory effects of iridoid glycosides fraction of Folium syringae leaves on TNBS-induced colitis in rats.
To investigate the effects and the protective mechanism of iridoid glycosides (IG) enriched from Folium syringae leaves on ulcerative colitis (UC) model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats.. UC in rats was induced by colonic administration with TNBS. IG (80, 160 and 240 mg/kg) was administered for 2 weeks to experimental colitis rats. The inflammatory degree was assessed by macroscopic score, histology and myeloperoxidase (MPO) activity. Nitric oxide (NO) and malondialdehyde (MDA) levels were measured with biochemical methods. The protein expressions of nuclear factor-kappaBp65 (NF-κBp65) and mRNA expressions of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and NF-κBp65, were determined by immunohistochemistry and real-time quantitative PCR, respectively.. IG significantly ameliorated macroscopic damage and histological changes, reduced the activity of MPO, depressed MDA and NO levels and effectively inhibited the protein and mRNA expressions of NF-κBp65, TNF-α and IL-6 in the colon tissues of experimental colitis in a dose-dependent manner. Moreover, the effects of IG (160 mg/kg and 240 mg/kg) were superior to salicylazosulfapyridine (150 mg/kg).. We demonstrated for the first time that IG possessed marked protective effects on experimental colitis through its antioxidation and inhibiting inflammatory mediators by down-regulation of the expressions of NF-κBp65. Topics: Animals; Anti-Inflammatory Agents; Base Sequence; Colitis; DNA Primers; Drugs, Chinese Herbal; Ethnopharmacology; Gene Expression; Glycosides; Interleukin-6; Iridoid Glycosides; Male; Malondialdehyde; Peroxidase; Phytotherapy; Plant Leaves; Plants, Medicinal; Rats; Rats, Sprague-Dawley; RNA, Messenger; Syringa; Transcription Factor RelA; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2011 |
Balance of meprin A and B in mice affects the progression of experimental inflammatory bowel disease.
MEP1A, which encodes the α subunit of meprin metalloproteinases, is a susceptibility gene for inflammatory bowel disease (IBD), and decreased intestinal meprin-α expression is associated with enhanced IBD in humans. Mice lacking meprin α (α knockout, αKO) have more severe colitis induced by dextran sulfate sodium (DSS) than wild-type (WT) mice, indicating an anti-inflammatory role for meprin A. Previous studies and those herein indicate the meprin B has proinflammatory activities. Therefore, mice lacking both meprin A and B (dKO mice) were generated to determine how their combined absence alters the inflammatory response to DSS. Unchallenged dKO mice grow and reproduce normally and have no obvious abnormal phenotype, except for a slightly elevated plasma albumin in both males and females and a lower urine creatinine level in dKO males. Upon oral administration of 3.5% DSS, the dKO mice have more severe colitis than the WT and βKO mice but significantly less than the αKO mice. The dKO mice lose more weight and have elevated MPO and IL-6 activities in the colon compared with WT mice. Systemic inflammation, monitored by plasma nitric oxide levels, is absent in DSS-treated dKO mice, unlike WT mice. The severity of experimental IBD in dKO mice is intermediate between αKO and WT mice. The data indicate that the absence of meprin A aggravates chronic inflammation and the lack of meprin B affords some protection from injury. Manipulation of the expression of meprin gene products may have therapeutic potential. Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Chronic Disease; Colitis; Dextran Sulfate; Disease Progression; Female; Genetic Predisposition to Disease; Inflammation Mediators; Inflammatory Bowel Diseases; Interleukin-6; Intestinal Mucosa; Male; Metalloendopeptidases; Mice; Mice, Knockout; Permeability; Peroxidase; Severity of Illness Index | 2011 |
Carbon monoxide liberated from carbon monoxide-releasing molecule exerts an anti-inflammatory effect on dextran sulfate sodium-induced colitis in mice.
Endogenous carbon monoxide (CO) is one of the three products of heme degradation by heme oxygenase-1 (HO-1) and exerts novel anti-inflammatory and anti-apoptotic effects as a gaseous second messenger. The purpose of this investigation was to determine whether exogenous CO could modulate intestinal inflammation.. Acute colitis was induced with 2% DSS in male C57BL/6 mice. CO-releasing molecule-2 (CORM-2; tricarbonyldichlororuthenium(II) dimer) was intraperitoneally administered twice daily and the disease activity index (DAI) was determined. We measured tissue-associated myeloperoxidase (MPO) activity as an index of neutrophil infiltration, and the production of keratinocyte chemoattractant (KC) and tumor necrosis factor-α (TNF-α) protein in the intestinal mucosa. In an in-vitro study, young adult mouse colonic epithelial (YAMC) cells were incubated with TNF-α, and KC mRNA/protein expression and nuclear translocation of nuclear factor-kappa B (NF-κB) were measured with or without CORM-2 treatment.. After DSS administration, DAI score increased in a time-dependent manner, and this increase was ameliorated by CORM-2 treatment. Increases in MPO activity and in the production of KC and TNF-α after DSS administration were significantly inhibited by CORM-2. TNF-α-induced KC production in YAMC cells was also inhibited by CORM-2 treatment. Further, nuclear translocation of NF-κB in YAMC cells was inhibited by CORM-2.. CORM-liberated CO significantly inhibited inflammatory response in murine colitis by inhibition of cytokine production in the colonic epithelium. These results suggest that CO could become a new therapeutic molecule for inflammatory bowel disease. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Carbon Monoxide; Chemotactic Factors; Colitis; Colon; Dextran Sulfate; Female; Gene Expression Regulation; Mice; Mice, Inbred C57BL; Organometallic Compounds; Peroxidase; Tumor Necrosis Factor-alpha | 2011 |
Effects of recombinant human intestinal trefoil factor on trinitrobenzene sulphonic acid induced colitis in rats.
Intestinal trefoil factor (ITF) has been proved to be effective in treatment of ulcerative colitis. However, the mechanisms of it remain unclear. In this study, we observed the effects of combined treatment with 5-aminosalicylic acid (5-ASA) and recombinant human ITF (rhITF) on the expression of Myeloperoxidase (MPO), nuclear factor-κB (NF-κB) and epidermal growth factor (EGF) in trinitrobenzene sulphonic acid (TNBS) induced colitis in rats. Forty Sprague-Dawley (SD) male rats which were induced to distal colitis by the colonic administration of TNBS, were randomly divided into four groups and colonically treated with normal saline (A), 5-ASA (B), rhITF (C), respectively. The macroscopic and histological changes of the colon, activities of MPO, expressions of serum EGF and tissue NF-κB were detected. The results showed that manifestation, colonic damage score and MPO activities of the rats treated with 5-ASA or/and rhITFs were improved, serum EGF production was augmented and expression of tissue NF-κB was down-regulated. Single usage of 5-ASA or rhITF had no significant difference, but combined using of them had more significant and noticeable effects compared to any single treatment. It could be concluded that topical treatment with 5-ASA and rhITF had beneficial effects in treating TNBS-induced colitis of rats and combined treatment was better than single treatment. It was possibly related to suppression of neutrophil infiltration, down-regulation expression of NF-κB and up-regulation expression of EGF. Topics: Animals; Colitis; Epidermal Growth Factor; Male; NF-kappa B; Peptides; Peroxidase; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Time Factors; Trefoil Factor-2; Trinitrobenzenesulfonic Acid | 2011 |
Nafamostat mesilate attenuates colonic inflammation and mast cell infiltration in the experimental colitis.
Serine proteases are important in the pathogenesis of intestinal inflammation. Recent studies have shown that nafamostat mesilate (NM) can inhibit the colonic mucosal inflammation induced by TNBS in rats. The aim of this study was to investigate the anti-inflammatory effects of NM on a DSS-induced colitis. Colitis was induced in female BALB/c mice by 5% dextran sulfate sodium (DSS) for 6 days. NM (2 or 20mg/kg body weight) was orally administered once a day for 6 days during treatment of the mice with DSS. The inflammatory response of the colon was assessed 1 week after DSS treatment. NM at a high dose, but not at a low dose significantly decreased disease activity index (DAI) and myeloperoxidase (MPO) induced by DSS. Furthermore, NM (20mg/kg) inhibited the production of tumor necrosis factor (TNF)-α, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in the colonic tissues treated with DSS. The increase in chymase activity by DSS treatment was also attenuated by the administration of NM (20mg/kg). NM (20mg/kg) significantly decreased the colonic mucosal injury and the infiltrated mast cell number induced by DSS. These results indicate that NM might inhibit the colonic inflammation through inhibition of both chymase activity and mast cell infiltration in colon tissues of DSS-induced colitis. Topics: Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzamidines; Blotting, Western; Cell Count; Chymases; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Female; Guanidines; Immunity, Mucosal; Intestinal Mucosa; Mast Cells; Mice; Mice, Inbred BALB C; Peroxidase | 2011 |
Treatment of mice with dextran sulfate sodium-induced colitis with human interleukin 10 secreted by transformed Bifidobacterium longum.
Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) the etiology of which has not yet been fully clarified. Cytokine interleukin-10 (IL-10) plays a central role in downregulating inflammatory cascade in UC and is likely a candidate for therapeutic intervention. However, its intravenous administration is costly and inconvenient. Therefore, we established a novel IL-10 delivery system by transforming a hIL-10-containing plasmid into B. longum (BL-hIL-10) and investigated its effects on 5% dextran sulfate sodium (DSS)-induced ulcerative colitis in mice and the possible underlying mechanism. Our results show that (1) hIL-10 was expressed and secreted into the culture supernatant of BL-hIL-10 after L-arabinose induction in vitro as examined by Western blot, enzyme-linked immunosorbent assay (ELISA) and RT-PCR; (2) addition of BL-hIL-10 culture supernatant had no cytotoxic effect and morphological alteration, but significantly inhibited the enhancement of proinflammatory cytokines by lipopolysaccharide (LPS) in THP-1 cells; (3) oral administration of BL-hIL-10 alleviated colitis syndrome of the model mice, attenuated colitis-activated NF-κB pathway measured by DNA-binding assay and colitis-elevated expression of proinflammatory cytokines examined with CCK cytotoxic kits, and upregulated CD4+CD25+Foxp3+ Treg in blood and mesenteric lymph nodes measured by flow cytometry. In conclusion, BL-hIL-10 as a novel oral hIL-10 delivery system has been successfully established and oral administration of BL-hIL-10 alleviated inflammatory damage of colonic tissue in the model mice by blocking the colitis-activated NF-κB pathway and upregulating CD4+CD25+Foxp3+ Treg in blood and mesenteric lymph nodes in mice. Topics: Administration, Oral; Animals; Bifidobacterium; Blotting, Western; Colitis; Cytokines; Dextran Sulfate; Drug Carriers; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Interleukin-10; Lipopolysaccharides; Male; Mice; Mice, Inbred BALB C; Monocytes; NF-kappa B; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; T-Lymphocytes, Regulatory | 2011 |
Dietary aloin, aloesin, or aloe-gel exerts anti-inflammatory activity in a rat colitis model.
Aloe has been a very popular folk remedy for inflammation-related pathological conditions despite the lack of studies reporting its efficacy in vivo. The present study evaluated the anti-inflammatory effects of aloe components (aloin, aloesin and aloe-gel) known to be biologically active in the rat model of colitis.. Male Sprague Dawley rats were fed experimental diets for 2 weeks before and during the induction of colitis. Drinking water containing 3% dextran sulfate sodium (DSS) was provided for 1 week to induce colitis. At the end of the experimental period, clinical and biochemical markers were compared.. Plasma leukotriene B(4) (LTB(4)) and tumor necrosis factor-α (TNF-α) concentrations were significantly decreased in all groups supplemented with aloe components compared to the colitis control group (p<0.05). Animals fed both a 0.1% and 0.5% aloesin supplemented diet showed colonic myeloperoxidase (MPO) activities which were decreased by 32.2% and 40.1%, respectively (p<0.05). Colonic mucosa TNF-α and interleukin-1ß (IL-1β) mRNA expressions were significantly reduced in all animals fed aloin, aloesin, or aloe-gel (p<0.05).. Dietary supplementation of aloe components ameliorates intestinal inflammatory responses in a DSS-induced ulcerative colitis rat model. In particular, aloesin was the most potent inhibitor. Further studies are required for a more complete understanding of the specific mechanism of the action of these supplements. Topics: Aloe; Animals; Anti-Inflammatory Agents, Non-Steroidal; Chromones; Colitis; Colon; Diet; Dietary Supplements; Disease Models, Animal; Emodin; Gels; Glucosides; Interleukin-1beta; Leukotriene B4; Male; Peroxidase; Plant Preparations; Rats; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha | 2011 |
Hookworm products ameliorate dextran sodium sulfate-induced colitis in BALB/c mice.
Several lines of evidence have shown that helminthiasis can significantly reduce disease severity in animal models of intestinal inflammation, airway inflammation/hyperreactivity, diabetes, and multiple sclerosis. Identification and characterization of helminth-derived immunomodulatory molecules that contribute to anticolitis effects could lead to new therapeutic approaches in inflammatory bowel diseases (IBDs) without the need for helminth infection. We evaluated the therapeutic potential of adult human hookworm, Ancylostoma ceylanicum, crude (Aw) and excreted/secreted (ES) products on dextran sulfate sodium (DSS)-induced colitis in BALB/c mice.. Colitis was induced by 5% DSS oral administration for 7 days. Clinical disease severity was monitored daily during concomitant intraperitoneal treatment with helminth-derived products. Additionally, several pathways of immunological modulation induced by A. ceylanicum products (MPO, EPO, Th1, Th2, and Th17 cytokine responses) in the inflamed intestinal microenvironment were assessed. Finally, the histopathological profile of the colon was characterized.. Hookworm products are able to modulate the potent proinflammatory response induced by DSS, mainly through the downregulation of Th1 and Th17 cytokines. These proteins also reduce clinical and colonic microscopic inflammation scores as well as EPO and MPO activity.. Ancylostoma ceylanicum Aw and ES mediators have an important therapeutic potential in experimental colitis in mice, which may provide a more socially acceptable form of therapy for patients with IBDs as opposed to using living worms. Our results support the urgency of further isolation and recombinant expression of active hookworm products responsible for the beneficial effects on colitis. Topics: Adult; Ancylostoma; Ancylostomiasis; Animals; Colitis; Cricetinae; Cytokines; Dextran Sulfate; Disease Models, Animal; Helminth Proteins; Humans; Inflammation; Male; Mesocricetus; Mice; Mice, Inbred BALB C; Peroxidase | 2011 |
Altered adrenal chromaffin cell function during experimental colitis.
The sympathetic nervous system regulates visceral function through the release of catecholamines and cotransmitters from postganglionic sympathetic neurons and adrenal chromaffin cells (ACCs). Previous studies have shown that norepinephrine secretion is decreased during experimental colitis due to the inhibition of voltage-gated Ca(2+) current (I(Ca)) in postganglionic sympathetic neurons. The present study examined whether colonic inflammation causes a similar impairment in depolarization-induced Ca(2+) influx in ACCs using the dextran sulfate sodium (DSS) model of acute colitis in mice. Alterations in ACC function during colitis were assessed using fura 2-acetoxymethyl ester Ca(2+) imaging techniques and perforated patch-clamp electrophysiology. In ACCs isolated from mice with DSS-induced acute colitis, the high-K(+)-stimulated increase in intracellular Ca(2+) concentration ([Ca(2+)](i)) was significantly reduced to 74% of the response of ACCs from control mice. Acute colitis caused a 10-mV hyperpolarization of ACC resting membrane potential, without a significant effect on cellular excitability. Delayed-rectifier K(+) and voltage-gated Na(+) current densities were significantly enhanced in ACCs from mice with DSS-induced acute colitis, with peak current densities of 154 and 144% that of controls, respectively. Importantly, acute colitis significantly inhibited I(Ca) in ACCs between -25 and +20 mV. Peak I(Ca) density in ACCs from mice with DSS-induced acute colitis was 61% that of controls. High-K(+)-induced increases in [Ca(2+)](i) were also reduced in ACCs from mice with 2,4,6-trinitrobenzene sulfonic acid-induced acute colitis and DSS-induced chronic colitis to 68 and 78% of the control responses, respectively. Our results suggest that, during colitis, voltage-dependent Ca(2+) influx is impaired in ACCs. Given the importance of Ca(2+) signaling in exocytosis, these alterations may decrease systemic catecholamine levels, which could play an important role in inflammatory bowel disease. This is the first demonstration of aberrant ACC function during experimental colitis. Topics: Analysis of Variance; Animals; Calcium; Calcium Channels; Chromaffin Cells; Colitis; Dextran Sulfate; Electrophysiology; Inflammation; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction | 2011 |
VPAC1 (vasoactive intestinal peptide (VIP) receptor type 1) G protein-coupled receptor mediation of VIP enhancement of murine experimental colitis.
Distinct roles of the two T cell G protein-coupled receptors for vasoactive intestinal peptide (VIP), termed VPAC1 and VPAC2, in VIP regulation of autoimmune diseases were investigated in the dextran sodium sulfate (DSS)-induced murine acute colitis model for human inflammatory bowel diseases. In mice lacking VPAC2 (VPAC2-KO), DSS-induced colitis appeared more rapidly with greater weight loss and severe histopathology than in wild-type mice. In contrast, DSS-induced colitis in VPAC1-KO mice was milder than in wild-type mice and VPAC2-KO mice. Tissues affected by colitis showed significantly higher levels of myeloperoxidase, IL-6, IL-1β and MMP-9 in VPAC2-KO mice than wild-type mice, but there were no differences for IL-17, IFN-γ, IL-4, or CCR6. Suppression of VPAC1 signals in VPAC2-KO mice by PKA inhibitors reduced the clinical and histological severity of DSS-induced colitis, as well as tissue levels of IL-6, IL-1β and MMP-9. Thus VIP enhancement of the severity of DSS-induced colitis is mediated solely by VPAC1 receptors. Topics: Animals; Body Weight; Colitis; Colon; Cyclic AMP-Dependent Protein Kinases; Dextran Sulfate; Disease Models, Animal; Female; Forkhead Transcription Factors; Gene Expression; Interleukin-17; Interleukin-1beta; Interleukin-6; Intestinal Mucosa; Male; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Peroxidase; Protein Kinase Inhibitors; Receptors, Vasoactive Intestinal Peptide, Type II; Receptors, Vasoactive Intestinal Polypeptide, Type I; Signal Transduction; T-Lymphocytes, Regulatory; Vasoactive Intestinal Peptide | 2011 |
Blocking TNF-α by combination of TNF-α- and TNFR-binding cyclic peptide ameliorates the severity of TNBS-induced colitis in rats.
Tumor necrosis factor alpha (TNF-α) has been implicated in the pathogenesis of Crohn's disease. TNF antagonists are effectively used to treat these patients, although the efficiency of different antagonists varies. In the present study we combined TNF-α binding cyclic peptide (TBCP) and TNFR1 binding cyclic peptide (TRBCP) to treat TNBS-induced colitis in rats for one week. The symptoms of colitis including bloody diarrhea, rectal prolapse, and a profound and sustained weight loss were significantly ameliorated and the colon inflammatory damage, both macroscopic and histological scores, MPO activity, and NO production were markedly decreased in rats by neutralization of TNF-α and blocking TNFR1, as compared with those in rats treated with irrelevant peptide or normal saline (P<0.05). The transcripts of IL-1β and IL-8, and the protein expression of TNF-α in rats treated with both TBCP and TRBCP were also down-regulated (P<0.05), while these proinflammatory cytokines remained unchanged in rats treated with irrelevant peptide or normal saline. These findings suggest that the combination of TNF-α- and TNFR1-binding peptide effectively improves the symptoms of TNBS-induced colitis and alleviates colonic pathological damages in rats. This combination may be a potent candidate for clinical treatment of the inflammatory bowel disease. Topics: Animals; Colitis; Colon; Gene Expression Regulation; Humans; Inflammation; Interleukin-1beta; Interleukin-8; Leukocytes; Male; Nitric Oxide; Peptide Library; Peptides, Cyclic; Peroxidase; Rats; Rats, Wistar; Receptors, Tumor Necrosis Factor, Type I; Transcription, Genetic; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2011 |
Urocortin 1 modulates immunosignaling in a rat model of colitis via corticotropin-releasing factor receptor 2.
Urocortins (UCNs) and their receptors are potent immunoregulators in the gastrointestinal (GI) tract, where they can exert both pro- and anti-inflammatory effects. We examined the contribution of Ucn1 and its receptors to the pathogenesis, progression, and resolution of colitis. Trinitrobenzene sulfonic acid was used to induce colitis in rats. Ucn1 mRNA and immunoreactivity (IR) were ubiquitously expressed throughout the GI tract under basal conditions. During colitis, Ucn1 mRNA levels fell below basal levels on day 1 then increased again by day 6, in association with an increase in the number of Ucn1-IR inflammatory cells. Ucn1-IR cells were also numerous in proliferating granulation tissue. In contrast to Ucn1 expression, average phosphorylated ERK1/2 (pERK1/2) expression rose above controls levels on day 1 and was very low on day 6 of colitis. Knockdown of corticotropin-releasing factor 2 (CRF(2)) but not CRF(1) by RNA interference during colitis significantly decreased the macroscopic lateral spread of ulceration compared with uninjected controls or animals with CRF(1) knockdown. After knockdown of CRF(2), but not of CRF(1) during colitis, edema resolution assessed microscopically was slowed, and myeloperoxidase activity remained elevated even at day 6. Ucn1 and TNF-α mRNA peaked earlier, whereas pERK1/2 activation was attenuated after CRF(2) knockdown. Thus we conclude that local CRF(2) and pERK1/2 activation is pivotal for macroscopic spread of colitis and resolution of edema. Elimination of CRF(2), but not CRF(1), results in uncoordinated immune and pERK1/2 signaling responses. Topics: Animals; Blotting, Western; Colitis; Disease Progression; Edema; Extracellular Signal-Regulated MAP Kinases; Immunohistochemistry; Kinetics; Male; Peroxidase; Phosphorylation; Rats; Rats, Sprague-Dawley; Receptors, Corticotropin-Releasing Hormone; Reverse Transcriptase Polymerase Chain Reaction; RNA Interference; RNA, Messenger; Signal Transduction; Trinitrobenzenesulfonic Acid; Urocortins | 2011 |
Biochemical and histological changes in the small intestine of mice with dextran sulfate sodium colitis.
The dextran sulfate sodium (DSS) model of colitis has been commonly utilized in mice to assess novel treatments for ulcerative colitis. Recent studies have indicated that morphological and biochemical changes extend to the small intestine (SI). This study aimed to characterize histological and biochemical changes in the SI during DSS colitis in wild-type (WT) and DPIV knock-out (DPIV(-/-) ) mice treated with saline or the DPIV inhibitors, Ile-Pyrr-(2-CN)*TFA or Ile-Thia. Groups (n = 10) of DPIV(-/-) and WT mice were orally gavaged twice daily with saline, Ile-Pyrr-(2-CN)*TFA or Ile-Thia. Mice consumed 2% DSS in drinking water for 6 days to induce colitis. Small intestinal tissue was assessed for histological changes, sucrase, and DPIV activity and neutrophil infiltration. Jejunal villus length was increased in all groups after 6 days DSS consumption (P < 0.05). Jejunal DPIV activity was significantly lower by 35% in WT mice receiving Ile-Pyrr-(2-CN)*TFA compared to saline controls. Jejunal MPO activity was significantly increased in the WT + saline and DPIV(-/-) + saline groups following DSS consumption, compared to WT and DPIV(-/-) controls at day 0. Increased sucrase activity was apparent at day 0 in DPIV(-/-) compared to WT mice (P < 0.05). We conclude that DSS-induced damage is not restricted to the colon, but also extends to the small intestine. Furthermore, reduced or absent DPIV activity resulted in functional adaptations to brush border enzyme activity. DPIV inhibitors are now a recognized therapy for type-II diabetes. The work presented here highlights the need to delineate any long-term effects of DPIV inhibitors on SI function, to further validate their safety and tolerability. Topics: Animals; Biomarkers; Colitis; Dextran Sulfate; Dipeptidyl Peptidase 4; Dipeptidyl-Peptidase IV Inhibitors; Disease Models, Animal; Ileum; Intestine, Small; Isoleucine; Jejunum; Mice; Mice, Inbred C57BL; Mice, Knockout; Microvilli; Neutrophil Infiltration; Peroxidase; Sucrase; Thiazoles; Time Factors | 2011 |
Natural almond skin reduced oxidative stress and inflammation in an experimental model of inflammatory bowel disease.
The aim of the present study was to examine the effects of natural almond skin (NS) powder in mice subjected to experimental colitis. Colitis was induced in mice by intracolonic instillation of dinitrobenzene sulfonic acid (DNBS). NS powder was administered daily orally (30 mg/kg). Four days after DNBS administration, colon NF-κB and p-JNK activation was increased as well as TNF-α and IL-1β productions. Neutrophil infiltration, by myeloperoxidase (MPO) activity, in the mucosa was associated with up-regulation of ICAM-1 and P-selectin. Immunohistochemistry for i-NOS, nitrotyrosine and poly (ADP-ribose) polymerase (PARP) showed an intense staining in the inflamed colon. Treatment with NS powder significantly reduced the appearance of diarrhea and body weight loss. This was associated with a significant reduction in colonic MPO activity. NS powder also reduced NF-κB and p-JNK activation, the pro-inflammatory cytokines release, the appearance of i-NOS, nitrotyrosine and PARP in the colon and reduced the up-regulation of ICAM-1 and the expression of P-selectin. The results of this study suggested that administration of NS powder may be beneficial for treatment of inflammatory bowel disease. Topics: Animals; Colitis; Colon; fas Receptor; I-kappa B Proteins; Inflammatory Bowel Diseases; Intercellular Adhesion Molecule-1; Interleukin-1beta; Lipid Peroxidation; Male; MAP Kinase Kinase 4; Mice; Neutrophil Infiltration; NF-kappa B; NF-KappaB Inhibitor alpha; Nitric Oxide Synthase Type II; Oxidative Stress; P-Selectin; Peroxidase; Phytotherapy; Plant Preparations; Poly(ADP-ribose) Polymerases; Prunus; Tumor Necrosis Factor-alpha; Tyrosine | 2011 |
Perinodal adipose tissue and mesenteric lymph node activation during reactivated TNBS-colitis in rats.
Colitis induced by trinitrobenzene sulfonic acid (TNBS) with reactivation is a good experimental model for studying inflammatory bowel disease pathogenesis and appropriate therapeutics. This experimental model allows the induction of colitis relapse and remission periods and the establishment of chronic disease features, such as the mesenteric adipose tissue alterations observed in Crohn's disease. Lymph node activation and the role of perinodal adipose tissue (PAT) have been poorly studied in this model. Thus, a study of the interactions of lymph nodes and PAT could help to elucidate the mechanisms behind IBD pathogenesis.. The purpose of this study was to examine lymph nodes and PAT alterations during reactivated TNBS-colitis in Wistar rats.. In this study, the alterations of PAT and lymph node cells during experimental colitis, induced by repeated intracolonic TNBS instillations, were evaluated, focusing on fatty acid and adipocytokine profile analysis and cytokines production, respectively.. Fatty acid analysis of PAT reveals an increase of ω-6 polyunsaturated fatty acids during colits, such as linoleic acid, gamma-linolenic acid and arachidonic acid. ω-6 arachidonic acid was not increased in lymph node cells or serum. PAT also produces elevated levels of pro- and anti-inflammatory adipokines during colitis. Lymph node cells release high levels of IFN-γ and TNF-α but not IL-10, characterizing the predominant Th-1 response associated with this disease. Nevertheless, T cells from animals with colitis demonstrated increased IFN-γ production via a COX-2-dependent mechanism after supplementation with ω-6 arachidonic acid, suggesting that PAT modification could contribute to the lymph node cell activation observed during colitis. Topics: Adipokines; Adipose Tissue; Animals; Arachidonic Acid; bcl-2-Associated X Protein; Colitis; Cyclooxygenase 2; Gene Expression Regulation; Inflammation; Interferon-gamma; Lymph Nodes; Male; Mesentery; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2011 |
Sex-dependent control of murine emotional-affective behaviour in health and colitis by peptide YY and neuropeptide Y.
Peptide YY (PYY) and neuropeptide Y (NPY) are involved in regulating gut and brain function. Because gastrointestinal inflammation is known to enhance anxiety, we explored whether experimental colitis interacts with genetic deletion (knockout) of PYY and NPY to alter emotional-affective behaviour.. Male and female wild-type, NPY (NPY(-/-) ), PYY (PYY(-/-) ) and NPY(-/-) ; PYY(-/-) double knockout mice were studied in the absence and presence of mild colitis induced by ingestion of dextran sulphate sodium (2%) in drinking water. Anxiety-like behaviour was tested on the elevated plus maze and open field, and depression-like behaviour assessed by the forced swim test.. In the absence of colitis, anxiety-like behaviour was increased by deletion of NPY but not PYY in a test- and sex-dependent manner, while depression-like behaviour was enhanced in NPY(-/-) and PYY(-/-) mice of either sex. The severity of DSS-induced colitis, assessed by colonic myeloperoxidase content, was attenuated in NPY(-/-) but not PYY(-/-) mice. Colitis modified anxiety- and depression-related behaviour in a sex-, genotype- and test-related manner, and knockout experiments indicated that NPY and PYY were involved in some of these behavioural effects of colitis.. These data demonstrate sex-dependent roles of NPY and PYY in regulation of anxiety- and depression-like behaviour in the absence and presence of colitis. Like NPY, the gut hormone PYY has the potential to attenuate depression-like behaviour but does not share the ability of NPY to reduce anxiety-like behaviour. Topics: Animals; Anxiety; Behavior, Animal; Colitis; Depression; Dextran Sulfate; Female; Gene Expression Regulation; Male; Mice; Mice, Knockout; Neuropeptide Y; Peptide YY; Peroxidase; Sex Characteristics | 2011 |
Fluoxetine inhibits NF-κB signaling in intestinal epithelial cells and ameliorates experimental colitis and colitis-associated colon cancer in mice.
Although fluoxetine, a selective serotonin reuptake inhibitor, is known to demonstrate anti-inflammatory activity, little information is available on the effect of fluoxetine regarding intestinal inflammation. This study investigates the role of fluoxetine in the attenuation of acute murine colitis by suppression of the NF-κB pathway in intestinal epithelial cells (IEC). Fluoxetine significantly inhibited activated NF-κB signals and the upregulated expression of interleukin-8 (IL-8) in COLO 205 colon epithelial cells stimulated with tumor necrosis factor-α (TNF-α). Pretreatment with fluoxetine attenuated the increased IκB kinase (IKK) and IκBα phosphorylation induced by TNF-α. In a murine model, administration of fluoxetine significantly reduced the severity of dextran sulfate sodium (DSS)-induced colitis, as assessed by the disease activity index, colon length, and histology. In addition, the DSS-induced phospho-IKK activation, myeloperoxidase activity, a parameter of neutrophil accumulation, and the secretion of macrophage-inflammatory protein-2, a mouse homolog of IL-8, were significantly decreased in fluoxetine-pretreated mice. Moreover, fluoxetine significantly attenuated the development of colon cancer in mice inoculated with azoxymethane and DSS. These results indicate that fluoxetine inhibits NF-κB activation in IEC and that it ameliorates DSS-induced acute murine colitis and colitis-associated tumorigenesis, suggesting that fluoxetine is a potential therapeutic agent for the treatment of inflammatory bowel disease. Topics: Animals; Cell Line; Cell Transformation, Neoplastic; Colitis; Colonic Neoplasms; Fluoxetine; Humans; I-kappa B Kinase; Interleukin-8; Intestinal Mucosa; Male; Mice; Mice, Inbred C57BL; Neutrophils; NF-kappa B; Peroxidase; Selective Serotonin Reuptake Inhibitors; Severity of Illness Index; Signal Transduction; Tumor Necrosis Factor-alpha | 2011 |
Activated and inactivated PPARs-γ modulate experimentally induced colitis in rats.
This study sought to define the mechanism by which PPAR-γ ligands affect the course of experimentally induced colitis in rats.. Inflammation was induced in Wistar rats by a single rectal administration of 2,4,6,-trinitrobenzene sulfonic acid (TNBS). The antagonist of PPARγ antagonist, bisphenol A diglycidyl ether (BADGE), was administrated intraperitoneally 120 mg/kg 4 times every other day. Rosiglitazone 8 mg/kg was administrated by gastric tube 4 times. Body weight was measured daily. After killing, the large intestinal tissue was weighed and collected for histopathologic and immunoenzymatic tests. Levels of IL-6, IL-10, and myeloperoxidase (MPO) were determined in serum and in intestinal homogenates.. Rats receiving rosiglitazone had higher body weight, whereas large intestine weight/length ratio was lower; histology showed fewer inflammatory markers. Rats receiving TNBS and TNBS along with BADGE had more intensive inflammatory changes. Rosiglitazone alone decreased expression of IL-6; used with TNBS it decreased expression of MPO in intestinal tissue, yet did not increase the expression of IL-10. Decreased levels of MPO indicate reduced neutrophil-dependent immune response. The antagonist of PPAR-γ increased IL-6 in serum and decreased IL-10 in intestinal homogenates. Bisphenol A diglycidyl ether administrated to healthy animals increases serum IL-6 levels.. Rosiglitazone inhibits experimental inflammation; administration of its selective antagonist abolishes this protective influence. Rosiglitazone inhibits expression of proinflammatory IL-6 and does not affect IL-10. Agonists of PPARs-γ are possibilities for inflammatory bowel disease prevention. Exogenous substances blocking PPARs-γ may contribute to development or relapse of nonspecific inflammatory bowel diseases. Topics: Animals; Body Weight; Colitis; Colon; Interleukin-10; Interleukin-6; Organ Size; Peroxidase; PPAR gamma; Rats; Rats, Wistar; Tissue Extracts | 2011 |
The effect of methylsulfonylmethane on the experimental colitis in the rat.
Methylsulfonylmethane (MSM), naturally occurring in green plants, fruits and vegetables, has been shown to exert anti-inflammatory and antioxidant effects. MSM is an organosulfur compound and a normal oxidative metabolite of dimethyl sulfoxide. This study was carried out to investigate the effect of MSM in a rat model of experimental colitis. Colitis was induced by intracolonic instillation of 1 ml of 5% of acetic acid. Rats were treated with MSM (400 mg/kg/day, orally) for 4 days. Animals were euthanized and distal colon evaluated histologically and biochemically. Tissue samples were used to measurement of malondialdehyde (MDA), myeloperoxidase (MPO), catalase (CAT), glutathione (GSH) and proinflammatory cytokine (TNF-α and IL-1β) levels. Results showed that MSM decreased macroscopic and microscopic colonic damage scores caused by administration of acetic acid. MSM treatment also significantly reduced colonic levels of MDA, MPO and IL-1β, while increased the levels of GSH and CAT compared with acetic acid-induced colitis group. It seems that MSM as a natural product may have a protective effect in an experimental ulcerative colitis. Topics: Animals; Anti-Inflammatory Agents; Catalase; Colitis; Dimethyl Sulfoxide; Glutathione; Interleukin-1beta; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Sulfones; Tumor Necrosis Factor-alpha | 2011 |
Influence of Shenqing Recipe on morphology and quantity of colonic interstitial cells of Cajal in trinitrobenzene sulfonic acid induced rat colitis.
To observe the influence of Shenqing Recipe (SQR), a kind of Traditional Chinese Medicine, on the morphology and quantity of colonic interstitial cells of Cajal (ICC) in trinitrobenzene sulfonic acid (TNBS)-induced rat colitis, and to investigate the possible mechanism of SQR in regulating intestinal dynamics.. Sixty rats were randomly divided into normal control, model 1, model 2, mesalazine, and high-dose, and low-dose SQR groups with 10 rats in each group. TNBS (10 mg) dissolved in 50% ethanol was instilled into the lumen of the rat colon of the latter five groups to induce colitis. On the 4th day after administration of TNBS, each treatment group was administered one of the following formulations by enteroclysis gavage once a day for 7 days: 600 mg•kg⁻¹•d⁻¹ mesalazine, 2.4 g•kg⁻¹•d⁻¹ SQR, and 1.2 g•kg⁻¹•d⁻¹ SQR. Model 2 rats received normal saline solution. After 7 days colonic samples were collected. While the colonic samples of model 1 group were collected on the 3rd day after TNBS administered. Ultrastructure of ICC in the damaged colonic tissues was observed with transmission electron microscope. Expression of c-kit protein in colonic tissue was determined by immunohistochemical staining and Western blot.. The ultrastructure of colonic ICC in the rat model of TNBS-induced colitis showed a severe injury, and administration of SQR or mesalazine reduced the severity of injury. Similarly, the expression of c-kit protein of TNBS-induced colitis rat model was significantly decreased compared with the normal control group (P < 0.05). Treatment with SQR or mesalazine significantly increased the expression of c-kit protein compared with the administration of control formulations (P < 0.05), especially the high-dose SQR group.. SQR could alleviate and repair the injured ICC, and improve its quantity, which might be involved in regulating intestinal motility. Topics: Animals; Colitis; Colon; Drugs, Chinese Herbal; Interstitial Cells of Cajal; Male; Medicine, Chinese Traditional; Mesalamine; Peroxidase; Proto-Oncogene Proteins c-kit; Random Allocation; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2011 |
Marginal zinc deficiency exacerbates experimental colitis induced by dextran sulfate sodium in rats.
We investigated the impact of Zn status on the maintenance of mucosal homeostasis. Rats were fed diets containing different amounts of Zn (30, 10, 5, <1 mg Zn/kg diet) for 21 d. Serum Zn concentrations were lower in rats fed marginally Zn-deficient (MZD; 5 mg Zn/kg diet) and severely Zn-deficient (<1 mg/kg) diets but not in those fed the marginally Zn-adequate diet (10 mg/kg) or the Zn-adequate (ZA; 30 mg/kg) group (P < 0.05). However, organ weights, colonic epithelial cell proliferation, and crypt fission did not differ between the MZD and ZA groups. We then evaluated whether MZD modulated dextran sulfate sodium (DSS)-induced colonic inflammation by administering 2% DSS to the MZD and ZA groups for 7 d. Myeloperoxidase activity and TNFα production increased in response to DSS in the MZD group (P < 0.03). Colonic permeability in the 2 groups did not differ after DSS administration. In a culture experiment using isolated mesenteric leukocytes, TNFα production was higher (P < 0.05) and TNF receptor type I (TNFR1) expression was detected in culture medium containing 20 and 30 μmol/L of Zn compared with culture medium lacking Zn supplementation. These results suggest that MZD exacerbated colitis by modulating the immune response through the impairment of TNFα production and TNFR1 expression rather than through the impairment of epithelial barrier function. Topics: Animals; Colitis; Dextran Sulfate; Gene Expression; Homeostasis; Intestinal Mucosa; Male; Peroxidase; Rats; Rats, Wistar; Receptors, Tumor Necrosis Factor, Type I; RNA, Messenger; Tumor Necrosis Factor-alpha; Zinc | 2011 |
The effect of pentoxifylline and its metabolite-1 on inflammation and fibrosis in the TNBS model of colitis.
TNBS-induced colitis has characteristics resembling human Crohn's disease including transmural inflammation, ulceration, and fibrosis. Current treatments target acute symptoms but do not necessarily prevent fibrotic complications of the disease. The aim of this study was to determine the effect of pentoxifylline and its primary metabolite (M-1) on fibrosis in the TNBS-induced colitis model. Myeloperoxidase activity and interleukin-18 are indicators of inflammation and were elevated in the TNBS model. The morphology damage score assesses colon damage and was also elevated in the TNBS model. Collagen as the indicator of fibrosis was quantified and visualized by the Sirius Red/Fast Green staining technique and collagen type I was assessed by Western analysis. Collagen was elevated in the TNBS-induced model. Pentoxifylline and M-1 treatment significantly attenuated colon damage and inflammation in TNBS-colitis (P<0.05). M-1 treatment significantly reduced the TNBS-induced increase in colon weight, colon thickness and total collagen content (P<0.05). Results suggest that pentoxifylline and M-1 inhibit intestinal fibrosis in this experimental model and may prove beneficial in the treatment of intestinal fibrosis associated with human Crohn's disease with the added benefit of inhibiting inflammation and ulceration. This is the first study to examine the effects of racemic M-1 in vivo and one of the few studies to examine the effect of drugs on both inflammation and fibrosis in an experimental model of colitis. Topics: Animals; Colitis; Collagen Type I; Colon; Disease Models, Animal; Female; Fibrosis; Inflammation; Interleukin-18; Intestinal Mucosa; Intestines; Organ Size; Pentoxifylline; Peroxidase; Rats; Rats, Sprague-Dawley; Stereoisomerism; Time Factors; Trinitrobenzenesulfonic Acid | 2011 |
Intracolonic infusion of fecal supernatants from ulcerative colitis patients triggers altered permeability and inflammation in mice: role of cathepsin G and protease-activated receptor-4.
Cathepsin G (Cat-G) is a neutrophil serine-protease found in the colonic lumen of ulcerative colitis (UC) patients. Cat-G is able to activate protease-activated receptor-4 (PAR(4) ) located at the apical side of enterocytes, leading to epithelial barrier disruption. However, the mechanisms through which Cat-G triggers inflammation are not fully elucidated. The aims of our study were to evaluate in vivo the effects of UC fecal supernatants and Cat-G on epithelial barrier function and inflammation, and the connection between these two parameters.. Male balb/c mice were used in this study. We evaluated the effect of a 2-hour intracolonic infusion of 1) fecal supernatants from UC patients pretreated or not with specific Cat-G inhibitor (SCGI); 2) PAR(4) -activating peptide (PAR(4) -AP); and 3) Cat-G on colonic myeloperoxidase (MPO) activity and paracellular permeability (CPP). The involvement of PAR(4) was assessed by pretreating animals with pepducin P4pal-10, which blocks PAR(4) signaling. We investigated the role of myosin light chain (MLC) kinase by using its inhibitor, ML-7, and we determined phosphorylated MLC (pMLC) levels in mice colonic mucosa.. UC fecal supernatants, Cat-G, and PAR(4) agonist increased both CPP and MPO activity in comparison with healthy subjects fecal supernatants. ML-7 inhibited the CPP increase triggered by Cat-G by 92.3%, and the enhanced MPO activity by 43.8%. Intracolonic infusion of UC fecal supernatant determined an increased phosphorylation level of MLC.. These observations support that luminal factors such as Cat-G play an important proinflammatory role in the pathogenesis of colitis, mainly depending on CPP increase by MLC phosphorylation. Topics: Administration, Rectal; Adolescent; Adult; Aged; Animals; Blotting, Western; Cathepsin G; Cell Membrane Permeability; Colitis; Colitis, Ulcerative; Colon; Feces; Humans; Intestinal Mucosa; Male; Mice; Mice, Inbred BALB C; Middle Aged; Peroxidase; Receptors, Thrombin; Young Adult | 2011 |
B-vitamin deficiency is protective against DSS-induced colitis in mice.
Vitamin deficiencies are common in patients with inflammatory bowel disease (IBD). Homocysteine (Hcys) is a thrombogenic amino acid produced from methionine (Met), and its increase in patients with IBD indicates a disruption of Met metabolism; however, the role of Hcys and Met metabolism in IBD is not well understood. We hypothesized that disrupted Met metabolism from a B-vitamin-deficient diet would exacerbate experimental colitis. Mice were fed a B(6)-B(12)-deficient or control diet for 2 wk and then treated with dextran sodium sulfate (DSS) to induce colitis. We monitored disease activity during DSS treatment and collected plasma and tissue for analysis of inflammatory tissue injury and Met metabolites. We also quantified Met cycle activity by measurements of in vivo Met kinetics using [1-(13)C-methyl-(2)H(3)]methionine infusion in similarly treated mice. Unexpectedly, we found that mice given the B-vitamin-deficient diet had improved clinical outcomes, including increased survival, weight maintenance, and reduced disease scores. We also found lower histological disease activity and proinflammatory gene expression (TNF-α and inducible nitric oxide synthase) in the colon in deficient-diet mice. Metabolomic analysis showed evidence that these effects were associated with deficient B(6), as markers of B(12) function were only mildly altered. In vivo methionine kinetics corroborated these results, showing that the deficient diet suppressed transsulfuration but increased remethylation. Our findings suggest that disrupted Met metabolism attributable to B(6) deficiency reduces the inflammatory response and disease activity in DSS-challenged mice. These results warrant further human clinical studies to determine whether B(6) deficiency and elevated Hcys in patients with IBD contribute to disease pathobiology. Topics: Analysis of Variance; Animals; Body Weight; Colitis; Dextran Sulfate; Gene Expression; Glutathione; Homocysteine; Inflammation; Interleukin-10; Kaplan-Meier Estimate; Male; Metabolomics; Methionine; Methylmalonic Acid; Mice; Mice, Inbred C57BL; Nitric Oxide Synthase Type II; Peroxidase; Pyridoxal Phosphate; S-Adenosylhomocysteine; Severity of Illness Index; Tumor Necrosis Factor-alpha; Vitamin B 12 Deficiency; Vitamin B 6 Deficiency | 2011 |
Topical application of glycyrrhizin preparation ameliorates experimentally induced colitis in rats.
To examine the efficacy of glycyrrhizin preparation (GL-p) in the treatment of a rat model of ulcerative colitis (UC).. Experimental colitis was induced by oral administration of dextran sodium sulfate. Rats with colitis were intrarectally administered GL-p or saline. The extent of colitis was evaluated based on body weight gain, colon wet weight, and macroscopic damage score. The expression levels of pro-inflammatory cytokines and chemokines in the inflamed mucosa were measured by cytokine antibody array analysis. The effect of GL-p on myeloperoxidase (MPO) activity in the inflamed mucosa and purified enzyme was assayed.. GL-p treatment significantly ameliorated the extent of colitis compared to sham treatment with saline. Cytokine antibody array analysis showed that GL-p treatment significantly decreased the expression levels of pro-inflammatory cytokines and chemokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, cytokine-induced neutrophil chemoattractant-2, and monocyte chemoattractant protein-1 in the inflamed mucosa. Furthermore, GL-p inhibited the oxidative activity of mucosal and purified MPO.. GL-p enema has a therapeutic effect on experimental colitis in rats and may be useful in the treatment of UC. Topics: Administration, Topical; Animals; Carboxymethylcellulose Sodium; Colitis; Cytokines; Dextran Sulfate; Enema; Glycyrrhizic Acid; Male; Peroxidase; Rats; Rats, Wistar | 2011 |
Impact of adrenomedullin on dextran sulfate sodium-induced inflammatory colitis in mice: insights from in vitro and in vivo experimental studies.
Although adrenomedullin (AM) is known to ameliorate inflammatory processes, few data exist regarding the effect of AM on inflammatory colitis. Therefore, we examined the effect of AM on inflammatory response in vitro and in vivo colitis model.. In mice experimental colitis induced by 3% dextran sulfate sodium (DSS) in drinking water for 7 days, AM with 225-900 μg/kg in 0.5 ml of saline or saline alone were given intraperitoneally once a day. In the in vitro experiment, we determined the cytokine response in THP-1 cell activated by lipopolysaccharide with or without AM of 10 nM. Additionally, we performed wound healing assay in Caco-2 cell interfered by DSS with or without AM of 100 nM.. In the colitis model, AM significantly reduced the disease activity index, histological score, and local production of inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in accordance with reduction of serum amyloid A levels. Secretion of TNF-α in lipopolysaccharide-stimulated THP-1 cells was significantly reduced in the presence of AM. The distance of wound healing interfered by 0.25% DSS was significantly improved in the presence of AM of 100 nM.. These results demonstrate that AM could ameliorate DSS-induced experimental colitis possibly through suppression of systemic and local production of cytokines such as TNF-α, associated with acceleration of ulcer reepithelialization and colon tissue regeneration. Topics: Adrenomedullin; Animals; Body Weight; Cell Line; Cell Movement; Colitis; Colon; Cytokines; Dextran Sulfate; Epithelium; Humans; Inflammation; Inflammation Mediators; Male; Mice; Mice, Inbred BALB C; Peroxidase; Serum Amyloid A Protein; Ulcer; Up-Regulation | 2011 |
The intestinal microbiota affect central levels of brain-derived neurotropic factor and behavior in mice.
Alterations in the microbial composition of the gastrointestinal tract (dysbiosis) are believed to contribute to inflammatory and functional bowel disorders and psychiatric comorbidities. We examined whether the intestinal microbiota affects behavior and brain biochemistry in mice.. Specific pathogen-free (SPF) BALB/c mice, with or without subdiaphragmatic vagotomy or chemical sympathectomy, or germ-free BALB/c mice received a mixture of nonabsorbable antimicrobials (neomycin, bacitracin, and pimaricin) in their drinking water for 7 days. Germ-free BALB/c and NIH Swiss mice were colonized with microbiota from SPF NIH Swiss or BALB/c mice. Behavior was evaluated using step-down and light preference tests. Gastrointestinal microbiota were assessed using denaturing gradient gel electrophoresis and sequencing. Gut samples were analyzed by histologic, myeloperoxidase, and cytokine analyses; levels of serotonin, noradrenaline, dopamine, and brain-derived neurotropic factor (BDNF) were assessed by enzyme-linked immunosorbent assay.. Administration of oral antimicrobials to SPF mice transiently altered the composition of the microbiota and increased exploratory behavior and hippocampal expression of BDNF. These changes were independent of inflammatory activity, changes in levels of gastrointestinal neurotransmitters, and vagal or sympathetic integrity. Intraperitoneal administration of antimicrobials to SPF mice or oral administration to germ-free mice did not affect behavior. Colonization of germ-free BALB/c mice with microbiota from NIH Swiss mice increased exploratory behavior and hippocampal levels of BDNF, whereas colonization of germ-free NIH Swiss mice with BALB/c microbiota reduced exploratory behavior.. The intestinal microbiota influences brain chemistry and behavior independently of the autonomic nervous system, gastrointestinal-specific neurotransmitters, or inflammation. Intestinal dysbiosis might contribute to psychiatric disorders in patients with bowel disorders. Topics: Amygdala; Analysis of Variance; Animals; Anti-Bacterial Agents; Behavior, Animal; Brain-Derived Neurotrophic Factor; Colitis; Colon; Cytokines; Germ-Free Life; Hippocampus; Intestine, Small; Mice; Mice, Inbred BALB C; Peroxidase; Sympathectomy; Vagotomy | 2011 |
Mycobacterium bovis Bacillus Calmette-Guérin killed by extended freeze-drying reduces colitis in mice.
Mycobacterium bovis Bacillus Calmette-Guérin (BCG), killed by extended freeze-drying (EFD), induces secretion of interleukin-10 and reduces lung inflammation in a mouse model of asthma. We investigated the effects of EFD BCG in mouse models of inflammatory bowel disease.. EFD BCG was administered subcutaneously to mice with colitis induced by dextran sodium sulfate (DSS), oxazolone, or adoptive transfer of CD4(+)CD45RB(high)Foxp3(-) T cells from C57Bl/6 Foxp3GFP mice to RAG2(-/-) mice.. EFD BCG, administered either before induction of DSS and oxazolone colitis or after development of acute or chronic DSS-induced colitis, reduced symptom scores, loss of body weight, and inflammation. Although transfer of CD4(+)CD45RB(high)Foxp3(-) cells induced colitis in RAG2(-/-) mice, administration of EFD BCG at the time of the transfer converted Foxp3(-) T cells to Foxp3(+) T cells and the mice did not develop colitis. EFD BCG protected mice from colitis via a mechanism that required expansion of T regulatory cells and production of interleukin-10 and transforming growth factor β. EFD BCG activated the retinoid X receptor (RXR)-α-peroxisome proliferator-activated receptor (PPAR)-γ heterodimer, blocked translocation of nuclear factor κB to the nucleus, and reduced colonic inflammation; it did not increase the number of colon tumors that formed in mice with chronic DSS-induced colitis.. EFD BCG controls severe colitis in mice by expanding T regulatory cell populations and PPAR-γ and might be developed to treat patients with inflammatory bowel disease. Topics: Animals; BCG Vaccine; Colitis; Colon; Dextran Sulfate; Forkhead Transcription Factors; Freeze Drying; Interleukin-1; Interleukin-10; Interleukin-6; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mycobacterium bovis; NF-kappa B; Oxazolone; Peroxidase; PPAR gamma; T-Lymphocytes, Regulatory; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha; Weight Loss | 2011 |
Lemon verbena infusion consumption attenuates oxidative stress in dextran sulfate sodium-induced colitis in the rat.
Inflammatory bowel diseases (IBD) consist of an uncontrolled intestinal inflammation leading to mucosal disruption. This inflammation is accompanied by an excessive production of reactive oxygen species (ROS). Polyphenols are micronutrients with antioxidative and anti-inflammatory properties, and may play an interesting role in the prevention of intestinal inflammation. Lemon verbena (Aloysia triphylla) infusion is a popular herbal infusion rich in polyphenols (flavones and verbascoside).. This study evaluated the preventive effects of lemon verbena infusion consumption against mild-to-moderate dextran sulfate sodium (DSS)-induced colitis in rats.. Wistar rats drank water or lemon verbena infusion for 14 days. On day 15, half of the rats received DSS (4%) in their drink for 7 days. At the end of the experimental period, the colon was taken for histopathological examination and determination of myeloperoxidase (MPO) activity, antioxidant enzyme activities (superoxide dismutase [SOD], glutathione peroxidase [GPx], glutathione reductase [GR], catalase [CAT]), glutathione and lipid peroxidation. Lymphocyte populations were determined in blood, mesenteric nodes and Peyer's patches.. Rats ingested daily 5.6 μmol of polyphenols. DSS reduced food intake and induced colitis, as reflected by histological lesions and increased MPO activity. Although these alterations were not significantly counteracted by lemon verbena consumption, the herbal infusion increased colonic SOD activity and decreased lipid peroxidation (malondialdehyde). Other oxidative stress markers (GPx, GR, CAT, glutathione) were not significantly modified.. Our study shows that the preventive consumption of lemon verbena infusion offered some antioxidative protection during experimental colitis by stimulating SOD activity and decreasing lipid peroxidation. Topics: Administration, Oral; Animals; Antioxidants; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Male; Oxidative Stress; Peroxidase; Plant Preparations; Rats; Superoxide Dismutase; Treatment Outcome; Verbena | 2011 |
N-Succinyl-chitosan systems for 5-aminosalicylic acid colon delivery: in vivo study with TNBS-induced colitis model in rats.
5-Aminosalicylic acid (5-ASA) loaded N-Succinyl-chitosan (SucCH) microparticle and freeze-dried system were prepared as potential delivery systems to the colon. Physicochemical characterization and in vitro release and swelling studies were previously assessed and showed that the two formulations appeared to be good candidates to deliver the drug to the colon. In this work the effectiveness of these two systems in the treatment of inflammatory bowel disease was evaluated. In vitro mucoadhesive studies showed excellent mucoadhesive properties of both the systems to the inflamed colonic mucosa. Experimental colitis was induced by rectal instillation of 2,4,6-trinitrobenzene sulfonic acid (TNBS) into male Wistar rats. Colon/body weight ratio, clinical activity score system, myeloperoxidase activity and histological evaluation were determined as inflammatory indices. The two formulations were compared with drug suspension and SucCH suspension. The results showed that the loading of 5-ASA into SucCH polymer markedly improved efficacy in the healing of induced colitis in rats. Topics: Absorption; Animals; Anti-Inflammatory Agents, Non-Steroidal; Chitosan; Colitis; Colon; Disease Models, Animal; Drug Carriers; Drug Delivery Systems; Freeze Drying; Intestinal Mucosa; Lymphocyte Activation; Male; Mesalamine; Organ Size; Peroxidase; Polymers; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2011 |
The atypical cannabinoid O-1602 protects against experimental colitis and inhibits neutrophil recruitment.
Cannabinoids are known to reduce intestinal inflammation. Atypical cannabinoids produce pharmacological effects via unidentified targets. We were interested in whether the atypical cannabinoid O-1602, reportedly an agonist of the putative cannabinoid receptor GPR55, reduces disease severity of dextran sulfate sodium (DSS) and trinitrobenzene sulfonic acid (TNBS)-induced colitis in C57BL/6N and CD1 mice.. DSS (2.5% and 4%) was supplied in drinking water for 1 week while TNBS (4 mg) was applied as a single intrarectal bolus.. Both treatments caused severe colitis. Injection of O-1602 (5 mg/kg intraperitoneally) significantly reduced macroscopic and histological colitis scores, and myeloperoxidase activity. The protective effect was still present in cannabinoid receptor 1 (CB₁) and 2 (CB₂) double knockout mice and mice lacking the GPR55 gene. To investigate a potential mechanism underlying the protection by O-1602 we performed neutrophil chemotactic assays. O-1602 concentration-dependently inhibited migration of murine neutrophils to keratinocyte-derived chemokine (KC), N-formyl-methionyl-leucyl-phenylalanine (fMLP), and the N-formyl-peptide receptor ligand WKYMVm. The inhibitory effect of O-1602 was preserved in neutrophils from CB₁/CB₂ double knockout and GPR55 knockout mice. No differences were seen in locomotor activity between O-1602-treated and control mice, indicating lack of central sedation by this compound.. Our data demonstrate that O-1602 is protective against experimentally induced colitis and inhibits neutrophil recruitment independently of CB₁, CB₂, and GPR55 receptors. Thus, atypical cannabinoids represent a novel class of therapeutics that may be useful for the treatment of inflammatory bowel diseases. Topics: Analysis of Variance; Animals; Cannabidiol; Cannabinoids; Chemotaxis, Leukocyte; Colitis; Colon; Cyclohexanes; Dextran Sulfate; Disease Models, Animal; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Motor Activity; Neutrophil Infiltration; Neutrophils; Peroxidase; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Receptors, Cannabinoid; Receptors, G-Protein-Coupled; Resorcinols; Trinitrobenzenesulfonic Acid | 2011 |
Impact of disrupting adenosine A₃ receptors (A₃⁻/⁻ AR) on colonic motility or progression of colitis in the mouse.
Pharmacological studies suggest that adenosine A₃AR influences motility and colitis. Functional A₃⁻/⁻AR knockout mice were used to prove whether A₃AR activation is involved in modulating either motility or colitis.. A₃AR was probed by polymerase chain reaction (PCR) genotyping, Western blot, and immunochemistry. Motility was assessed in vivo by artificial bead-expulsion, stool-frequency, and FITC-dextran transit. Colitis was induced with dextran sodium sulfate (DSS) in A₃⁻/⁻AR or wildtype (WT) age- and sex-matched controls. Progression of colitis was evaluated by histopathology, changes in myeloperoxidase (MPO), colon length, CD4(+) -cells, weight-loss, diarrhea, and the guaiac test.. Goat anti-hu-A₃ antiserum identified a 66 kDa immunogenic band in colon. A₃AR-immunoreactivity is expressed in SYN(+) -nerve varicosities, s-100(+) -glia, and crypt cells, but not 5-HT(+) (EC), CD4(+) (T), tryptase(+) (MC), or muscle cells. A₃AR immunoreactivity in myenteric ganglia of distal colon >> proximal colon by a ratio of 2:1. Intestinal transit and bead expulsion were accelerated in A₃⁻/⁻AR mice compared to WT; stool retention was lower by 40%-60% and stool frequency by 67%. DSS downregulated A₃AR in epithelia. DSS histopathology scores indicated less mucosal damage in AA₃⁻/⁻AR mice than WT. A₃⁻/⁻AR phenotype protected against DSS-induced weight loss, neutrophil (MPO), or CD4(+) -T cell infiltration, colon shortening, change in splenic weight, diarrhea, or occult-fecal blood.. Functional disruption of A₃AR in A₃⁻/⁻AR mice alters intestinal motility. We postulate that ongoing release of adenosine and activation of presynaptic-inhibitory A₃AR can slow down transit and inhibit the defecation reflex. A₃AR may be involved in gliotransmission. In separate studies, A₃⁻/⁻AR protects against DSS colitis, consistent with a novel hypothesis that A₃AR activation contributes to development of colitis. Topics: Animals; CD4 Lymphocyte Count; Colitis; Colon; Defecation; Dextran Sulfate; Diarrhea; Female; Gastrointestinal Transit; Genotype; Mice; Mice, Knockout; Myenteric Plexus; Occult Blood; Organ Size; Peroxidase; Receptor, Adenosine A3; Spleen; Time Factors; Weight Loss | 2011 |
TRPV1 and TRPA1 function and modulation are target tissue dependent.
The nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) families of growth factors regulate the sensitivity of sensory neurons. The ion channels transient receptor potential vanilloid 1 (TRPV1) and transient receptor potential channel, subfamily A, member 1 (TRPA1), are necessary for development of inflammatory hypersensitivity and are functionally potentiated by growth factors. We have shown previously that inflamed skin exhibits rapid increases in artemin mRNA with slower, smaller increases in NGF mRNA. Here, using mice, we show that, in inflamed colon, mRNA for both growth factors increased with a pattern distinct from that seen in skin. Differences were also seen in the pattern of TRPV1 and TRPA1 mRNA expression in DRG innervating inflamed skin and colon. Growth factors potentiated capsaicin (a specific TRPV1 agonist) and mustard oil (a specific TRPA1 agonist) behavioral responses in vivo, raising the question as to how these growth factors affect individual afferents. Because individual tissues are innervated by afferents with unique properties, we investigated modulation of TRPV1 and TRPA1 in identified afferents projecting to muscle, skin, and colon. Muscle and colon afferents are twice as likely as skin afferents to express functional TRPV1 and TRPA1. TRPV1 and TRPA1 responses were potentiated by growth factors in all afferent types, but compared with skin afferents, muscle afferents were twice as likely to exhibit NGF-induced potentiation and one-half as likely to exhibit artemin-induced potentiation of TRPV1. Furthermore, skin afferents showed no GDNF-induced potentiation of TRPA1, but 43% of muscle and 38% of colon afferents exhibited GDNF-induced potentiation. These results show that interpretation of afferent homeostatic mechanisms must incorporate properties that are specific to the target tissue. Topics: Animals; Calcium; Cholera Toxin; Colitis; Colon; Cytokines; Dermatitis; Disease Models, Animal; Fluorescent Dyes; Freund's Adjuvant; Gene Expression Regulation; Intercellular Signaling Peptides and Proteins; Male; Mice; Mice, Inbred C57BL; Muscles; Neural Pathways; Peroxidase; Receptors, Cytokine; RNA, Messenger; Skin; Time Factors; Transient Receptor Potential Channels; TRPA1 Cation Channel; TRPV Cation Channels; Wheat Germ Agglutinins | 2011 |
The effect of phosphodiesterase-5 inhibition by sildenafil citrate on inflammation and apoptosis in rat experimental colitis.
To investigate the effect of sildenafil citrate (SIL) on the extent of tissue integrity, oxidant-antioxidant status and apoptosis in rats with colitis.. Colitis was induced by trinitrobenzenesulphonic acid (TNBS) in 40% ethanol (30 mg/ml; 0.8 ml) given intrarectally to Sprague-Dawley rats. Sildenafil (25 mg/kg/day) was administered after the induction of colitis and the treatment was continued for 7 days. Other groups received subcutaneously either N(G)-nitro- L-arginine methyl ester (l-NAME; 25 mg/kg) or N(G)-nitro-d-arginine methyl ester (d-NAME; 25 mg/kg) before SIL. After decapitation, the distal colon was scored and stored for the measurement of malondialdehyde (MDA) level, glutathione (GSH) content, myeloperoxidase (MPO) activity and apoptosis. Oxidant generation was monitored by using chemiluminescence (CL). Blood was collected for tumor necrosis factor (TNF)-α and interleukin (IL)-10 assays.. The macroscopic lesion score of the colitis group was reduced by SIL (p < 0.01) and this effect was abolished by l-NAME (p < 0.01). Increase in colonic MDA along with a concomitant decrease in GSH of the colitis group was reversed by SIL (p < 0.01 and p < 0.001, respectively). l-NAME prevented the effect of SIL on GSH content (p < 0.001). Sildenafil also reduced the elevated MPO of the colitis group (p < 0.001) and this effect was reversed by L-NAME (p < 0.01). Increase in lucigenin CL and serum TNF-α levels in the colitis group were also prevented by SIL (p < 0.001 and p < 0.01, respectively).. Sildenafil is beneficial in TNBS-induced rat colitis partially by nitric oxide-dependent mechanisms via the maintenance of oxidant-antioxidant status, prevention of apoptosis, superoxide production and cytokine release. Topics: Animals; Apoptosis; Colitis; Female; Glutathione; Inflammatory Bowel Diseases; Interleukin-10; Male; Malondialdehyde; NG-Nitroarginine Methyl Ester; Peroxidase; Phosphodiesterase 5 Inhibitors; Piperazines; Purines; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Sildenafil Citrate; Sulfones; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2011 |
Correlation of neutrophil and monocyte derived interleukin-1 receptor antagonist and interleukin-8 with colitis severity in the rabbit.
Activated neutrophils and monocytes produce interleukin (IL)-8, a pro-inflammatory chemokine, but also IL-1 receptor antagonist (IL-1ra), which is an anti-inflammatory cytokine. We were interested to see the profiles of IL-8 and IL-1ra in the colonic tissue and in the peripheral blood leukocytes (PBL) during the development of immune complex induced colitis in rabbits. IL-1ra and IL-8 in PBL were measured in 26 rabbits at time 0 h, 24 h, and 48 h after induction of colitis. The colons were removed at 48 h for measuring myeloperoxidase (MPO), ulcer area, IL-1ra and IL-8. Epithelial damage, crypt abscess formation and leukocyte infiltration of the colonic tissue were major features of this colitis model. During the development of colitis, there was an increase in circulating neutrophils and monocytes (P<0.0001), but not lymphocytes. Likewise, elevated amounts of IL-1ra (P=0.0001) and IL-8 (P=0.0219) production by PBL were observed following induction of colitis. Flow cytometry revealed major source of IL-1ra was monocytes, while the main sources of IL-8 were neutrophils and monocytes. There was correlation between MPO and ulcer area (Rs=0.6327, P<0.0001). At 24 h, PBL from MPOHigh group (n=11) showed increased IL-1ra (P=0.027) and IL-8 (P=0.0128) levels vs MPOLow group (n=15). IL-8 production by PBL showed correlation with tissue MPO (Rs=0.4273, P=0.0295). The colitis in this model was associated with an increase in circulating monocytes and neutrophils, which released increased amounts of IL-8 and IL-1ra. Further, IL-8 and IL-1ra showed correlation with the severity of colitis. These observations should significantly further understandings on the role of neutrophils and monocytes in the immunopathogenesis of ulcerative colitis. Topics: Animals; Colitis; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Immunohistochemistry; Interleukin 1 Receptor Antagonist Protein; Interleukin-8; Male; Monocytes; Neutrophils; Peroxidase; Rabbits; Severity of Illness Index | 2011 |
The effect of stinging nettle (Urtica dioica) seed oil on experimental colitis in rats.
This study investigated the effect of Urtica dioica, known as stinging nettle, seed oil (UDO) treatment on colonic tissue and blood parameters of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. Experimental colitis was induced with 1 mL of TNBS in 40% ethanol by intracolonic administration with a 8-cm-long cannula with rats under ether anesthesia, assigned to a colitis group and a colitis+UDO group. Rats in the control group were given saline at the same volume by intracolonic administration. UDO (2.5 mL/kg) was given to the colitis+UDO group by oral administration throughout a 3-day interval, 5 minutes later than colitis induction. Saline (2.5 mL/kg) was given to the control and colitis groups at the same volume by oral administration. At the end of the experiment macroscopic lesions were scored, and the degree of oxidant damage was evaluated by colonic total protein, sialic acid, malondialdehyde (MDA), and glutathione levels, collagen content, tissue factor activity, and superoxide dismutase and myeloperoxidase activities. Colonic tissues were also examined by histological and cytological analysis. Pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-1β, and interleukin-6), lactate dehydrogenase activity, and triglyceride and cholesterol levels were analyzed in blood samples. We found that UDO decreased levels of pro-inflammatory cytokines, lactate dehydrogenase, triglyceride, and cholesterol, which were increased in colitis. UDO administration ameliorated the TNBS-induced disturbances in colonic tissue except for MDA. In conclusion, UDO, through its anti-inflammatory and antioxidant actions, merits consideration as a potential agent in ameliorating colonic inflammation. Topics: Administration, Oral; Animals; Antioxidants; Cholesterol; Colitis; Colon; Disease Models, Animal; Female; Glutathione; Inflammation; Interleukin-6; L-Lactate Dehydrogenase; Male; Malondialdehyde; N-Acetylneuraminic Acid; Oxidative Stress; Peroxidase; Plant Oils; Rats; Rats, Wistar; Seeds; Superoxide Dismutase; Triglycerides; Trinitrobenzenesulfonic Acid; Urtica dioica | 2011 |
On the benefit of whey-cultured Lactobacillus casei in murine colitis.
The objective of this study was to examine the prophylactic and therapeutic effect of whey-cultured Lactobacillus casei (L. casei) in a murine model of colitis. Colitis was induced by intracolonic administration of a mixture of 2,4,6-trinitrobenzenesulphonic acid (TNBS)/absolute ethanol in male Wistar rats. Animals were divided into 5 groups including sham (normal group), control (vehicle-treated), positive control (dexamethasone 1 mg/kg/day, orally), prevention (10(8) cfu L. casei/day, orally, 14 days before induction of colitis), and treatment (10(8) cfu L. casei/day, orally, 14 days after induction of colitis). After 14-days treatment, the animals were sacrificed on the day 15. Distal colons were removed for examining histological and biochemical assays. Biomarkers including TNF-α, myeloperoxidase (MPO), and lipid peroxidation (LPO) were measured in the homogenate of colon. Results indicated an apparent improvement in colon histopathology scores, TNF-α, MPO, and LPO in the treatment group, whereas prevention group did not demonstrate positive efficacy in prevention of colonic damage. It is concluded that L. casei grown in whey culture is very effective in ameliorating both biochemical and histopathological markers of colitis if used post induction of colitis but not if used before induction of colitis. The difference between effects of L. casei when used pre-colitis and post-colitis confirms its mechanism of action as an anti toxic stress agent. Further studies should be made in IBD patients. Topics: Administration, Rectal; Animals; Anti-Inflammatory Agents; Colitis; Colon; Dexamethasone; Disease Models, Animal; Ethanol; Lacticaseibacillus casei; Lipid Peroxidation; Male; Mice; Milk Proteins; Peroxidase; Probiotics; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Whey Proteins | 2011 |
Effects of peroxisome proliferator-activated receptors-gamma ligands on dextran sodium sulphate-induced colitis in rats.
Recent studies indicate the involvement of peroxisone proliferator-activated receptor-γ (PPAR-γ) in the inflammatory reaction. The exact mechanism of PPAR-γ action has not been elucidated. It is supposed that PPAR-γ regulates transcription of genes responsible for encoding cytokines involved in the inflammatory response. The latest studies, carried out to explain the pathogenesis of non-specific colitis, confirm beneficial effects of PPAR-γ agonists on attenuation of colon inflammation. The aim of the present study was to assess the effects of nuclear PPAR-γ activity on the course of experimental acute colitis induced by intragastric administration of dextran sodium sulphate (DSS) using the PPAR-γ agonist rosiglitazone and the antagonist BADGE in rats. Colitis in Wistar rats was induced by 1.5% DSS administered in drinking water for 8 days. Animals with induced colitis received rosiglitazone, bisphenol A diglycidyl ether (BADGE) or both substances. After decapitation, colons were macroscopically and histopathologically evaluated. Levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α) and myeloperoxidase (MPO) were determined in serum and colon homogenates using ELISA. In rats with experimentally induced colitis receiving rosiglitazone, the inflammatory reaction was found to be markedly limited; ulceration, oedema and infiltration activity were reduced. The activated PPAR-γ inhibit the expression of proinflammatory factors, such as IL-6, TNF-α, and neutrophil chemotaxis, which was evidenced by MPO reduction in serum and colon homogenates mediated by rosiglitazone. The positive effects of rosiglitazone on expression of IL-10 were also demonstrated. During the short period of observation, BADGE did not increase histopathological inflammatory markers. Topics: Animals; Behavior, Animal; Benzhydryl Compounds; Carcinogens; Colitis; Colon; Cytokines; Dextran Sulfate; Epoxy Compounds; Hypoglycemic Agents; Intestinal Mucosa; Intestine, Large; Ligands; Peroxidase; PPAR gamma; Rats; Rats, Wistar; Rosiglitazone; Thiazolidinediones | 2011 |
Antibiotic treatment with ampicillin accelerates the healing of colonic damage impaired by aspirin and coxib in the experimental colitis. Importance of intestinal bacteria, colonic microcirculation and proinflammatory cytokines.
Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for their anti-inflammatory, analgesic and antipyretic effects, however their use is associated with the broad spectrum of side effects observed in human as well as the experimental animals. Despite damaging activity of NSAIDs in upper gastrointestinal (GI) tract, these drugs exert deleterious influence in lower GI tract, including colon. The role of GI microflora in the pathogenesis of NSAIDs-induced experimental colonic damage is not completely understood. The aim of this study was 1) to evaluate the relative importance of the GI microflora on the experimental colonic damage in the presence of caused by NSAID, and 2) to assess the efficacy of antibiotic treatment with ampicillin on the process of healing of colitis. We compared the effect of vehicle, ASA applied 40 mg/kg intragastrically (i.g.) or the selective cyclooxygenase (COX)-2 inhibitor, celecoxib (25 mg/kg i.g.) without or with ampicillin treatment (800 mg/kg i.g.) administered throughout the period of 10 days, on the intensity of TNBS-induced colitis in rats. The severity of colonic damage, the alterations in the colonic blood flow (CBF) and myeloperoxidase (MPO) activity, the mucosal expression of TNF-α, IL-1β, COX-2, VEGF and iNOS and the plasma concentration of TNF-α and IL-1β were assessed. In all rats, the faeces samples as well as those from the colonic mucosa, blood, liver and spleen underwent microbiological evaluation for intestinal bacterial species including Escherichia coli and Enterococcus spp. The administration of TNBS resulted in macroscopic and microscopic lesions accompanied by the significant fall in the CBF, an increase in tissue weight and 4-5-fold rise in the MPO activity and a significant increase in the plasma IL-1β and TNF-α levels. ASA or celecoxib significantly increased the area of colonic lesions, enhanced MPO activity and caused the marked increase in colonic tissue weight and plasma IL-1β and TNF-α levels, as well as an overexpression of mRNA for IL-1β and TNF-α, COX-2, VEGF and iNOS in the colonic tissue. ASA and coxib also resulted also in a significant increase of E. coli counts in the stool at day 3 and day 10 day of the observation compared with the intact rats. Moreover, E. coli translocation from the colon to the blood and extraintestinal organs such as liver and spleen in the group of rats treated without or with ASA and coxib. E. coli was the most common bacteria isolated from these organs. Tr Topics: Ampicillin; Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Bacterial Load; Bacterial Translocation; Celecoxib; Chemokines; Colitis; Colon; Cyclooxygenase 2 Inhibitors; Enterococcus; Escherichia coli; Feces; Humans; Intestinal Mucosa; Intestines; Male; Microcirculation; Peroxidase; Pyrazoles; Rats; Rats, Wistar; Sulfonamides; Trinitrobenzenesulfonic Acid | 2011 |
Nitric oxide-releasing aspirin but not conventional aspirin improves healing of experimental colitis.
To determine the effect of non-selective cyclooxygenase (COX) inhibitors, selective COX-2 inhibitors and nitric oxide (NO)-releasing aspirin in the healing of ulcerative colitis.. Rats with 2,4,6 trinitrobenzenesulfon-ic acid (TNBS)-induced colitis received intragastric (ig) treatment with vehicle, aspirin (ASA) (a non-selective COX inhibitor), celecoxib (a selective COX-2 inhibitor) or NO-releasing ASA for a period of ten days. The area of colonic lesions, colonic blood flow (CBF), myeloperoxidase (MPO) activity and expression of proinflammatory markers COX-2, inducible form of nitric oxide synthase (iNOS), IL-1β and tumor necrosis factor (TNF)-α were assessed. The effects of glyceryl trinitrate (GTN), a NO donor, and 2-(4-carboxyphenyl)-4,5-dihydro-4,4,5,5-tetramethyl-1H-imidazolyl-1-oxy-3-oxide, onopotassium salt (carboxy-PTIO), a NO scavenger, administered without and with ASA or NO-ASA, and the involvement of capsaicin-sensitive afferent nerves in the mechanism of healing the experimental colitis was also determined.. Rats with colitis developed macroscopic and microscopic colonic lesions accompanied by a significant decrease in the CBF, a significant rise in colonic weight, MPO activity and plasma IL-1β and TNF-α levels. These effects were aggravated by ASA and 5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-(trifluoromethyl)-1H-pyrazole (SC-560), but not celecoxib and counteracted by concurrent treatment with a synthetic prostaglandin E₂ (PGE₂) analog. Treatment with NO-ASA dose-dependently accelerated colonic healing followed by a rise in plasma NO(x) content and CBF, suppression of MPO and downregulation of COX-2, iNOS, IL-1β and TNF-α mRNAs. Treatment with GTN, the NO donor, significantly inhibited the ASA-induced colonic lesions and increased CBF, while carboxy-PTIO or capsaicin-denervation counteracted the NO-ASA-induced improvement of colonic healing and the accompanying increase in the CBF. These effects were restored by co-treatment with calcitonin gene related peptide (CGRP) and NO-ASA in capsaicin-denervated animals.. NO-releasing ASA, in contrast to ASA, COX-1 inhibitors, and SC-560, accelerated the healing of colitis via a mechanism involving NO mediated improvement of microcirculation and activation of sensory nerves releasing CGRP. Topics: Animals; Aspirin; Colitis; Colon; Cyclooxygenase 2; Cyclooxygenase Inhibitors; Denervation; Dinoprostone; Humans; Interleukin-1beta; Intestinal Mucosa; Male; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha | 2011 |
Antioxidative potential of a combined therapy of anti TNFα and Zn acetate in experimental colitis.
To evaluate whether combination therapy with anti-tumour necrosis factor α (TNFα) antibody and Zn acetate is beneficial in dextran sodium sulphate (DSS) colitis.. Colitis was induced in CD1-Swiss mice with 5% DSS for 7 d. The experimental mice were then randomised into the following subgroups: standard diet + DSS treated (induced colitis group); standard diet + DSS + subcutaneous 25 μg anti-TNFα treated group; Zn acetate treated group + DSS + subcutaneous 25 μg anti-TNFα; standard diet + DSS + subcutaneous 6.25 μg anti-TNFα treated group and Zn acetate treated group + DSS + subcutaneous 6.25 μg anti-TNFα. Each group of mice was matched with a similar group of sham control animals. Macroscopic and histological features were scored blindly. Homogenates of the colonic mucosa were assessed for myeloperoxidase activity as a biochemical marker of inflammation and DNA adducts (8OH-dG) as a measure of oxidative damage.. DSS produced submucosal erosions, ulcers, inflammatory cell infiltration and cryptic abscesses which were reduced in both groups of mice receiving either anti-TNFα alone or combined with zinc. The effect was more pronounced in the latter group (vs Zn diet, P < 0.02). Myeloperoxidase activity (vs controls, P < 0.02) and DNA adducts, greatly elevated in the DSS fed colitis group (vs controls, P < 0.05), were significantly reduced in the treated groups, with a more remarkable effect in the group receiving combined therapy (vs standard diet, P < 0.04).. DSS induces colonic inflammation which is modulated by the administration of anti-TNFα. Combining anti-TNFα with Zn acetate offers marginal benefit in colitis severity. Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Antibodies; Antioxidants; Colitis; Deoxyguanosine; Dextran Sulfate; Diet; Male; Mice; Oxidative Stress; Peroxidase; Random Allocation; Tumor Necrosis Factor-alpha; Zinc Acetate | 2011 |
Ameliorating effects of short-chain inulin-like fructans on the healing stage of trinitrobenzene sulfonic acid-induced colitis in rats.
We evaluated the ameliorating effects of short-chain inulin-like fructans (SIF) with different degrees of polymerization (DP) on the healing stage of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. The rats were assigned to 3 groups 10 d after the colitis induction, and fed for 24 d on a control diet or diet including 60 g of DP4 or DP8/kg. The fecal myeloperoxidase (MPO) activity and IgA concentration were monitored every 7 d. The colonic MPO activities and cecal concentrations of organic acids, lactobacilli, bifidobacteria, mucin and IgA were measured at the end of the study. DP4, but not DP8, significantly reduced the colonic inflammation accompanied by higher cecal concentrations of short-chain fatty acids, propionate in particular, and lactic acid-producing bacteria. DP4 therefore accelerated the healing process of TNBS-induced colitis, even when the treatment was initiated after inducing colitis. Topics: Animals; Bacteria; Colitis; Diet; Fructans; Immunoglobulin A; Inulin; Male; Peroxidase; Polymerization; Rats; Rats, Sprague-Dawley; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2011 |
Halofuginone, a specific inhibitor of collagen type 1 synthesis, ameliorates oxidant colonic damage in rats with experimental colitis.
To evaluate the effect of halofuginone on trinitrobenzene sulfonic acid (TNBS)-induced colonic injury, rats were given halofuginone (40 microg/kg, intraperitoneally) or saline 1 h before the induction of colitis, and the injections were continued twice daily for 3 days until they were decapitated. High macroscopic and microscopic damage scores, elevated colonic wet weights, colonic myeloperoxidase activity, malondialdehyde and tissue collagen level, and luminol chemiluminescence values, and marked reduction in glutathione level of the saline-treated colitis group were all reversed by treatment with halofuginone. In conclusion, halofuginone exerts beneficial effects in TNBS-induced colonic inflammation in rats. The anti-inflammatory effects of halofuginone appear to involve suppression of neutrophil accumulation, preservation of endogenous glutathione, and inhibition of reactive oxidant generation. Halofuginone also shows antifibrotic effect via inhibition of tissue collagen production. The present data encourage possible use of the antifibrotic halofuginone as an anti-inflammatory agent in improving oxidative injury in colitis. Topics: Animals; Anti-Inflammatory Agents; Colitis; Collagen; Collagen Type I; Colon; Female; Glutathione; Luminescence; Male; Malondialdehyde; Organ Size; Peroxidase; Piperidines; Protein Synthesis Inhibitors; Quinazolinones; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2010 |
Oral administration of curcumin emulsified in carboxymethyl cellulose has a potent anti-inflammatory effect in the IL-10 gene-deficient mouse model of IBD.
Curcumin is a tumeric-derived, water-insoluble polyphenol with potential beneficial health effects for humans. It has been shown to have preventive as well as therapeutic effects in chemically induced murine models of colitis. To investigate whether curcumin exerts a similar effect on the spontaneous colitis in interleukin (IL)-10 gene-deficient mice, we gavaged these mice daily for 2 weeks with 200 mg/kg per day curcumin emulsified in carboxymethyl cellulose, a food additive generally used as a viscosity modifier. Mice fed the curcumin/carboxymethyl cellulose mixture and those receiving carboxymethyl cellulose alone demonstrated similar reductions in histological injury score and colon weight/length ratio compared to water-fed controls. However, significant reductions in pro-inflammatory cytokine release in intestinal explant cultures were only seen in mice treated with the curcumin mixture. Our data demonstrate that in IL-10 gene-deficient mice, both oral curcumin and carboxymethyl cellulose, appear to have modifying effects on colitis. However, curcumin has additional anti-inflammatory effects mediated through a reduced production of potent pro-inflammatory mucosal cytokines. Topics: Administration, Oral; Analysis of Variance; Animals; Carboxymethylcellulose Sodium; Colitis; Curcumin; Disease Models, Animal; Emulsions; Enzyme-Linked Immunosorbent Assay; Interferon-gamma; Interleukin-10; Interleukin-17; Mice; Peroxidase | 2010 |
(-)-Epigallocatechin-3-gallate reduces experimental colon injury in rats by regulating macrophage and mast cell.
The ameliorative effect of (-)-epigallocatechin-3-gallate (EGCG) on inflammatory bowel disease (IBD) induced by ethanol 2,4,6-trinitrobenzene sulfonic acid (TNBS) was studied in 7-week-old male rats. Intestinal lesions were measured as an increase in myeloperoxidase (MPO) activity in mucosa. The supplementation of EGCG significantly inhibited MPO activity and histamine levels in the distal colon mucosa. The EGCG inhibited macrophage chemotaxis toward N-formyl-L-methionyl-L-leucyl-L-phenylalanine in a concentration-dependent manner. These observations confirmed that EGCG can ameliorate acute experimental colitis by the suppression of mast cells and macrophage activities. Topics: Animals; Catechin; Chemotaxis; Colitis; Histamine; Macrophages; Male; Mast Cells; N-Formylmethionine Leucyl-Phenylalanine; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2010 |
N-Methyl-D-aspartate receptor antagonism decreases motility and inflammatory activation in the early phase of acute experimental colitis in the rat.
Inflammatory bowel diseases are accompanied by severe motility disorders. The aim of our study was to investigate whether the blockade of peripheral N-methyl-D-aspartate (NMDA)-sensitive glutamate receptors (NMDA-Rs) alters motility changes in chemically induced acute colitis and how this modulation is accomplished.. The inflammatory and motility changes in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis were studied in anaesthetized Wistar rats following treatment with the natural NMDA-R antagonist kynurenic acid (KynA) or SZR-72, a blood-brain barrier-permeable synthetic KynA analogue. The macrohaemodynamics, serosal microcirculation (visualized by intravital videomicroscopy), plasma levels of tumour necrosis factor alpha (TNF-alpha), inflammatory enzyme activities (xanthine oxidoreductase (XOR), myeloperoxidase (MPO) and nitric oxide synthase (NOS)), and colonic motility (with a strain-gauge technique) were evaluated 17 h after colitis induction and compared with the control conditions.. The TNBS enema induced a systemic hyperdynamic circulatory reaction, increased the serosal capillary blood flow, significantly elevated the mucosal XOR, MPO and NOS activities and augmented the colonic motility relative to the controls. The NMDA-R antagonist treatment with KynA or SZR-72 significantly reduced the XOR, NOS and MPO activities, decreased the motility and increased the tone of the colon.. These data demonstrate a potential modulatory mechanism of NMDA-R in altered colonic motility in TNBS colitis. Inhibition of the enteric NMDA-Rs may provide a therapeutic option via which to influence intestinal hypermotility, microcirculatory changes and inflammatory activation simultaneously. Topics: Analysis of Variance; Animals; Blood Pressure; Colitis; Colon; Disease Models, Animal; Excitatory Amino Acid Antagonists; Gastrointestinal Motility; Inflammation; Kynurenic Acid; Male; Nitric Oxide Synthase; Peroxidase; Random Allocation; Rats; Rats, Wistar; Receptors, N-Methyl-D-Aspartate; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Xanthine Oxidase | 2010 |
Orally administered glucans from the edible mushroom Pleurotus pulmonarius reduce acute inflammation in dextran sulfate sodium-induced experimental colitis.
Polysaccharides are one of the most potent mushroom-derived substances exhibiting anti-inflammatory and immunomodulatory properties. The aims of the present study were to determine whether orally administered glucans from the edible mushroom Pleurotus pulmonarius could attenuate or prevent the development of experimental colitis in mice. Colonic inflammation was induced in mice by treatment with 3.5 % dextran sulfate sodium (DSS) for 18 d. Before or after DSS administration, mice were given hot water solubles (HWS) or mycelium extract (ME) (2 or 20 mg per mouse) daily in their food. Colonic damage was macroscopically and histologically evaluated. Inflammation was assessed by changes in colon length, TNF-alpha levels released by colonic samples in organ culture and myeloperoxidase (MPO) activity. mRNA levels of pro-inflammatory (IL-1beta) and anti-inflammatory (IL-10) cytokines in colonic samples were determined by quantitative real-time RT-PCR. P. pulmonarius glucans attenuated and prevented the development of symptoms associated with DSS-induced colitis. High doses of HWS and ME blocked colon shortening, suppressed MPO activity and improved macroscopic score in all treatment groups. In addition, histological damage from colitis was reduced by HWS and ME at all doses. The tissue levels of TNF-alpha protein were significantly decreased and correlated with degree of inflammation and macroscopic score. All treatments significantly attenuated the increased DSS-mediated expression levels of IL-1beta. We conclude that the different glucan preparations (HWS or ME) harvested from P. pulmonarius when orally administered to DSS-treated mice attenuate the development of colonic inflammation, suggesting putative clinical utility for these extracts in the treatment of colitis. Topics: Administration, Oral; Animals; Cecum; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; DNA, Complementary; Female; Glucans; Inflammation; Interleukin-10; Interleukin-1beta; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Neutrophils; Peroxidase; Phosphoric Monoester Hydrolases; Pleurotus; Reverse Transcriptase Polymerase Chain Reaction; Tumor Necrosis Factor-alpha | 2010 |
Colitis affects the smooth muscle and neural response to motilin in the rabbit antrum.
The underlying mechanisms of gastric dysfunction during or after an episode of intestinal inflammation are poorly understood. This study investigated the effects of colitis on the contractile effects of motilin, an important endocrine regulator of gastric motility, in the antrum.. Myeloperoxidase (MPO) activity, NF-kappaB activity and motilin receptor density were determined in the antrum of rabbits 5 days after the induction of 2,4,6-trinitrobenzenesulphonic acid colitis. Smooth muscle and neural responses to motilin were studied in antral smooth muscle strips in vitro.. Colitis did not affect MPO activity, but increased NF-kappaB activity in the antrum. Motilin receptor density in the antrum was not affected. Under control conditions, motilin induced a slowly developing tonic smooth muscle contraction. Five days post-inflammation, tonic contractions to motilin were reduced and preceded by a rapid initial contraction. Other kinases were recruited for the phosphorylation of myosin light chain (MLC) (a multi-functional MLC kinase), and for the inhibition of MLC phosphatase (Rho kinase in addition to protein kinase C) to mediate the motilin-induced contractions during inflammation. Colitis potentiated the cholinergic neural on-contractions in the antrum. This was associated with a hyper-reactivity to motilin and an increased muscle response to ACh.. Colitis altered the course of the motilin-induced smooth muscle contraction in the antrum. This involved changes in the kinases phosphorylating MLC. Increased cholinergic excitability to motilin in the antrum may play a role in the pathogenesis of inflammation-associated gastric motility disorders. Topics: Animals; Colitis; Enzyme Activation; Female; Male; Motilin; Muscle Contraction; Muscle, Smooth; Myosin Light Chains; Myosin-Light-Chain Kinase; Myosin-Light-Chain Phosphatase; NF-kappa B; Peroxidase; Phosphorylation; Protein Kinase C; Pyloric Antrum; Rabbits; Receptors, Gastrointestinal Hormone; Receptors, Neuropeptide; rho-Associated Kinases; Signal Transduction; Trinitrobenzenesulfonic Acid | 2010 |
Insulin-like growth factor 1-coated sutures improve anastomotic healing in an experimental model of colitis.
: Exogenously applied insulin-like growth factor (rhIGF-1) may improve normal intestinal healing. This study examined the effect of rhIGF-1-coated sutures on anastomotic healing in experimental colitis.. : Acute colitis was induced in rats by dextran sodium sulphate (DSS). Inflammation was assessed by clinical Disease Activity Index (DAI), myeloperoxidase (MPO) measurement and histological examination. A distal colonic anastomosis was performed using sutures coated with rhIGF-1 dissolved in poly(D,L-lactide) (PDLLA) under general anaesthetic. Anastomotic healing was evaluated histologically, and by hydroxyproline measurement and bursting parameters after 1, 3 and 7 days, and compared with healthy, DSS and DSS + PDLLA controls.. : DAI, MPO and histological inflammation scores were significantly increased in all animals treated with DSS. Bursting occurred less often within the anastomotic line on day 3 in the IGF group than in DSS controls (three versus eight of ten). On day 7, the IGF group had significantly increased histological healing scores (mean(s.e.m.) 12.5(0.7) versus 9.2(0.8) (P < 0.050)) and hydroxyproline content (4.6(0.3) versus 3.6(0.1) mg/g tissue; P < 0.050) compared with DSS controls.. : IGF-1-coated sutures improve important aspects of anastomotic healing in rats with experimental colitis. Topics: Anastomosis, Surgical; Animals; Colitis; Dextran Sulfate; Female; Insulin-Like Growth Factor Binding Protein 1; Peroxidase; Rats; Rats, Sprague-Dawley; Surgical Wound Dehiscence; Sutures; Wound Healing | 2010 |
Inhalation of carbon monoxide ameliorates TNBS-induced colitis in mice through the inhibition of TNF-α expression.
Carbon monoxide (CO), long considered a toxic gas, has recently been shown to mediate anti-inflammatory effects in various animal models. The aim of this study was to investigate whether the inhalation of CO ameliorated 2,4,6-trinitrobenzine sulfonic acid (TNBS)-induced colitis in mice.. The CO treatment group was exposed to CO gas at a concentration of 200 ppm in a closed cage starting on the day when TNBS was administered and throughout the remaining study period. The distal colon was removed, and ulcerative lesions were subsequently evaluated with macroscopic damage scores. Furthermore, thiobarbituric acid (TBA)-reactive substances and tissue-associated myeloperoxidase (MPO) activity in colonic mucosa were measured as indices of lipid peroxidation and neutrophil infiltration. The expressions of TNF-α in colonic mucosa were also measured by enzyme-linked immunosorbent assay. In additional experiments in vitro, CD4(+) T cells isolated from the spleen were stimulated with anti-CD3/CD28 Ab, and the cells and supernatants were collected and evaluated for TNF-α expression.. The increased colonic damage after TNBS administration was significantly inhibited by the treatment with CO. Furthermore, CO significantly inhibited the increases in TBA-reactive substances, MPO activity and TNF-α production in colonic mucosa after the induction of TNBS colitis. In CD4(+) T cells isolated from mice treated with CO inhalation, the production of TNF-α was significantly inhibited.. The inhalation of CO protected mice from developing intestinal inflammation. Based on these data, the beneficial effects of CO in a murine colitis model may be attributed to its anti-inflammatory properties. Topics: Administration, Inhalation; Animals; Anti-Inflammatory Agents; Antibodies; Carbon Monoxide; CD28 Antigens; CD3 Complex; CD4-Positive T-Lymphocytes; Cells, Cultured; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Male; Mice; Mice, Inbred C57BL; Peroxidase; RNA, Messenger; Spleen; Thiobarbituric Acid Reactive Substances; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2010 |
On the benefit of Teucrium in murine colitis through improvement of toxic inflammatory mediators.
Regarding the role of free radicals in pathogenesis of inflammatory bowel disease (IBD), we were interested to investigate the effects of Teucrium persicum with approved antioxidant and anti-inflammatory properties in an experimental model of colitis. Immunologic colitis was induced by rectal administration of a mixture of 2,4,6-trinitrobenzene sulphonic acid (TNBS) and ethanol through rubber cannula into rats. Three different doses of Teucrium (100, 200, and 400 mg/kg) were gavaged in a duration of 10 days to rats. Endpoint markers of colitis included macroscopic and microscopic examination of colon tissue and measuring colonic cells concentrations of tumor necrosis factor-alpha (TNF-alpha), interlukin-1beta (IL-1beta), total antioxidant power as ferric reducing antioxidant power (FRAP), myeloperoxidase (MPO), and lipid peroxidation as thiobarbitoric acid-reactive substance (TBARS). Teucrium at all doses improved both macroscopic and histological damages of rats with colitis. Teucrium reduced colonic MPO activity and concentrations of cellular lipid peroxides, TNF-alpha, and IL-1beta, with a concomitant increase in FRAP value in rats with colitis. It is concluded that beneficial effects of Teucrium in experimental colitis is mediated through its antioxidant and anti-inflammatory potentials. Examination of this herbal medicine in patients with IBD as a supplement would further reveal the potential of Teucrium. Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Ethanol; Gastrointestinal Agents; Inflammation Mediators; Interleukin-1beta; Lipid Peroxidation; Male; Oxidative Stress; Peroxidase; Plant Components, Aerial; Plant Preparations; Rats; Rats, Wistar; Teucrium; Thiobarbituric Acid Reactive Substances; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2010 |
Granisetron ameliorates acetic acid-induced colitis in rats.
Inflammatory bowel disease (IBD) is a chronically relapsing inflammation of the gastrointestinal tract, of which the definite etiology remains ambiguous. Considering the adverse effects and incomplete efficacy of currently administered drugs, it is indispensable to explore new candidates with more desirable therapeutic profiles. 5-HT( 3) receptor antagonists have shown analgesic and anti-inflammatory properties in vitro and in vivo. This study aims to investigate granisetron, a 5-HT( 3) receptor antagonist, in acetic acid-induced rat colitis and probable involvement of 5-HT(3) receptors. Colitis was rendered by instillation of 1 mL of 4% acetic acid (vol/vol) and after 1 hour, granisetron (2 mg/kg), dexamethasone (1 mg/kg), meta-chlorophenylbiguanide (mCPBG, 5 mg/kg), a 5-HT( 3) receptor agonist, or granisetron + mCPBG was given intraperitoneally. Twenty-four hours following colitis induction, animals were sacrificed and distal colons were assessed macroscopically, histologically and biochemically (malondialdehyde, myeloperoxidase, tumor necrosis factor-alpha, interleukin-1 beta and interleukin-6). Granisetron or dexamethasone significantly (p < .05) improved macroscopic and histologic scores, curtailed myeloperoxidase activity and diminished colonic levels of inflammatory cytokines and malondialdehyde. The protective effects of granisetron were reversed by concurrent administration of mCPBG. Our data suggests that the salutary effects of granisetron in acetic acid colitis could be mediated by 5-HT(3) receptors. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Biguanides; Colitis; Colon; Dexamethasone; Disease Models, Animal; Gastrointestinal Agents; Granisetron; Inflammation Mediators; Injections, Intraperitoneal; Interleukin-1beta; Interleukin-6; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Serotonin, 5-HT3; Serotonin 5-HT3 Receptor Antagonists; Serotonin Antagonists; Serotonin Receptor Agonists; Tumor Necrosis Factor-alpha | 2010 |
Dietary medium-chain triglycerides prevent chemically induced experimental colitis in rats.
The effects of dietary medium-chain triglycerides (MCTs) on experimental colitis induced by 2,4,6-trinitrobenzene sulphonic acid (TNBS) were investigated in rats. Male Wistar rats were given an intracolonic injection of TNBS and were then fed liquid diets containing MCTs or corn oil (AIN93) as controls. Serum and tissue samples were collected 1 week after TNBS enema. The severity of colitis was evaluated pathologically, and tissue myeloperoxidase (MPO) activity was measured. Furthermore, messenger RNA (mRNA) and protein levels for inflammatory cytokines and a chemokine were assessed by reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. In another set of experiments, the protein expression of Toll-like receptor (TLR)-4 in the colon was measured 1 week after feeding of liquid diets. To investigate the effects of MCTs on macrophages, RAW246.7 macrophages were incubated with media containing albumin conjugated with MCT or linoleic acid, which is the major component of corn oil. Then, the production of tumor necrosis factor-alpha (TNF-alpha) was measured. Dietary MCTs blunted significantly the protein levels of TLR-4 in the colon. Furthermore, the expression of TLR-4 was significantly blunted in RAW264.7 cells incubated with MCTs compared with cells incubated with linoleic acid. Induction of interleukin 1beta (IL-1beta), TNF-alpha, and macrophage inflammatory protein-2 (MIP-2) in the colon was attenuated by dietary MCT. Furthermore, MPO activities in the colonic tissue were significantly blunted in animals fed the MCT diets compared with those fed the control diets. As a result, dietary MCTs improved chemically induced colitis significantly. MCTs most likely are useful for the therapy of inflammatory bowel disease as an anti-inflammatory immunomodulating nutrient. Topics: Animals; Cells, Cultured; Chemokine CXCL2; Colitis; Colon; Endotoxins; Interleukin-1beta; Male; Mice; Peroxidase; Rats; Rats, Wistar; Toll-Like Receptor 4; Triglycerides; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2010 |
Dipeptidyl peptidase expression during experimental colitis in mice.
We have previously demonstrated that inhibition of dipeptidyl peptidase (DP) activity partially attenuates dextran sulfate sodium (DSS) colitis in mice. The aim of this study was to further investigate the mechanisms of this protection.. Wildtype (WT) and DPIV(-/-) mice consumed 2% DSS in drinking water for 6 days to induce colitis. Mice were treated with saline or the DP inhibitors Ile-Pyrr-(2-CN)*TFA or Ile-Thia. DP mRNA and enzyme levels were measured in the colon. Glucagon-like peptide (GLP)-2 and GLP-1 concentrations were determined by radioimmunoassay, regulatory T-cells (Tregs) by fluorescence activated cell sorting (FACS) on FOXp3+T cells in blood, and neutrophil infiltration assessed by myeloperoxidase (MPO) assay.. DP8 and DP2 mRNA levels were increased (P < 0.05) in WT+saline mice compared to untreated WT mice with colitis. Cytoplasmic DP enzyme activity was increased (P < 0.05) in DPIV(-/-) mice at day 6 of DSS, while DP2 activity was increased (P < 0.05) in WT mice with colitis. GLP-1 (63%) and GLP-2 (50%) concentrations increased in WT+Ile-Pyrr-(2-CN)*TFA mice compared to day-0 controls. MPO activity was lower in WT+Ile-Thia and WT+Ile-Pyrr-(2-CN)*TFA treated mice compared to WT+saline (P < 0.001) at day 6 colitis.. DP expression and activity are differentially regulated during DSS colitis, suggesting a pathophysiological role for these enzymes in human inflammatory bowel disease (IBD). DP inhibitors impaired neutrophil recruitment and maintenance of the Treg population during DSS-colitis, providing further preclinical evidence for the potential therapeutic use of these inhibitors in IBD. Finally, DPIV appears to play a critical role in mediating the protective effect of DP inhibitors. Topics: Animals; Colitis; Colon; Dextran Sulfate; Dipeptidyl-Peptidase IV Inhibitors; Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; Disease Models, Animal; Glucagon-Like Peptide 1; Glucagon-Like Peptide 2; Humans; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; Peroxidase; T-Lymphocytes, Regulatory | 2010 |
All-trans retinoic acid ameliorates trinitrobenzene sulfonic acid-induced colitis by shifting Th1 to Th2 profile.
Inflammatory bowel disease is characterized with uncontrolled immune response in inflamed mucosa, with dominance of Th1 cells. Recently, all-trans retinoic acid has been shown that can lead T-cell response by suppressing Th17 development via retinoic acid receptor (RAR), but it is still unknown whether all-trans retinoic acid can modulate Th1 response of inflammatory bowel disease. In the experiment, we investigated the effect of all-trans retinoic acid on trinitrobenzene sulfonic acid (TNBS)-induced murine colitis, and the possible mechanism. Mice were intraperitoneally treated daily with all-trans retinoic acid (the agonist of RAR-alpha) or LE135 (the antagonist of RAR-alpha) or medium, and sacrificed 6 days later. Colon was collected for histological analysis and myeloperoxidase (MPO) activity measurement. Lamina propria mononuclear cells (LPMCs) were isolated, cultured, and assayed for the expressions of T-bet and GATA-3 by the use of Western blot and for cytokine levels by the use of ELISA. All-trans retinoic acid treatment inhibited inflammatory responses as shown by lower histological inflammatory scores and MPO activity, compared with LE135 and medium groups. Furthermore, in LPMCs culture supernatants, the levels of Th1 cytokines (INF-gamma, IL-12, and TNF-alpha) were decreased while those of Th2 cytokines (IL-4 and IL-10) were increased significantly in all-trans retinoic acid-treated mice. In addition, T-bet expression in LPMCs was inhibited and GATA-3 expression was up-regulated in all-trans retinoic acidtreated mice. On the contrary, LE135 showed the reverse effects in colon inflammation and cytokine profile. By shifting Th1 to Th2 profile in inflamed mucosa, all-trans retinoic acid down-regulates inflammatory response and ameliorates acute TNBS-induced colitis, which suggests the ligand of RAR-alpha-based pharmaceutical strategies for managing inflammatory bowel disease. Topics: Animals; Cells, Cultured; Colitis; Colon; Cytokines; Dibenzazepines; GATA3 Transcription Factor; Male; Mice; Mucous Membrane; Peroxidase; Retinoids; T-Box Domain Proteins; Th1 Cells; Th2 Cells; Tretinoin; Trinitrobenzenesulfonic Acid | 2010 |
Exploring the interplay of barrier function and leukocyte recruitment in intestinal inflammation by targeting fucosyltransferase VII and trefoil factor 3.
Intestinal mucosal integrity is dependent on epithelial function and a regulated immune response to injury. Fucosyltransferase VII (Fuc-TVII) is an essential enzyme required for the expression of the functional ligand for E- and P-selectin. Trefoil factor 3 (TFF3) is involved in both protecting the intestinal epithelium against injury as well as aiding in wound repair following injury. The aim of the present study was to assess the interplay between barrier function and leukocyte recruitment in intestinal inflammation. More specifically, we aimed to examine how targeted disruption of Fuc-TVII either in wild-type or TFF3(-/-) mice would alter their susceptibility to colonic injury. TFF3 and Fuc-TVII double-knockout mice (TFF3/Fuc-TVII(-/-) mice) were generated by mating TFF3(-/-) and Fuc-TVII(-/-) mice. Colitis was induced by administration of dextran sodium sulfate (DSS) (2.5% wt/vol) in the drinking water. Changes in baseline body weight, diarrhea, and fecal blood were assessed daily. Upon euthanasia, extents of colonic inflammation were assessed macroscopically, microscopically, and through quantification of myeloperoxidase (MPO) activity. Colonic lymphocyte subpopulations were assessed at 6 days after administration of DSS by flow cytometry and immunohistochemistry. No baseline intestinal inflammation was found in TFF3/Fuc-TVII(-/-), TFF3(-/-), Fuc-TVII(-/-), or wild-type mice. Loss of Fuc-TVII resulted in a reduction in disease severity whereas TFF3(-/-) mice were markedly more susceptible to DSS-induced colitis. Remarkably, the loss of Fuc-TVII in TFF3(-/-) mice markedly decreased the severity of DSS-induced colitis as evidenced by reduced weight loss, diarrhea, decreased colonic MPO levels and improved survival. Furthermore, the loss of TFF3 resulted in increased severity of spontaneous colitis in IL-2/beta-microglobulin-deficient mice. These studies highlight the importance of the interplay between factors involved in the innate immune response, mucosal barrier function, and genes involved in regulating leukocyte recruitment and other aspects of the immune response. Topics: Animals; beta 2-Microglobulin; Chemotaxis, Leukocyte; Colitis; Dextran Sulfate; Diarrhea; Disease Models, Animal; Fucosyltransferases; Immunity, Innate; Interleukin-2; Intestinal Mucosa; Leukocytes; Melena; Mice; Mice, Inbred C57BL; Mice, Knockout; Mucins; Peroxidase; Severity of Illness Index; Time Factors; Trefoil Factor-3; Weight Loss | 2010 |
The role of the complement and contact systems in the dextran sulfate sodium-induced colitis model: the effect of C1 inhibitor in inflammatory bowel disease.
The complement and contact systems may be involved in the pathophysiological process of inflammatory bowel disease (IBD). C1 inhibitor (C1INH) is the most important inhibitor of both the complement and contact systems. We evaluated the role of these systems and the effect of both active and inactive forms of C1INH (iC1INH) in dextran sulfate sodium (DSS)-induced colitis mouse model. Three percent DSS was used in drinking water to induce colitis in complement C3-deficient (C3(-/-)) mice, bradykinin type 2 receptor deficient (Bk(2)R(-/-)) mice, and C57BL/6 mice. After ten days DSS exposure, C3(-/-) mice exhibited markedly less weight loss than wild-type (WT) mice (12 +/- 3.3% vs. 30 +/- 1.2%, P < 0.05) and developed a milder disease-activity index (DAI), histological score, colon shortening, and myeloperoxidase (MPO) elevation (P < 0.05, respectively). The Bk(2)R(-/-) mice were not protected from the disease. Seven-day treatment with either native C1INH or iC1INH reduced the severity of the disease in WT mice, as indicated by decreased weight loss (15 +/- 1.8%, 14 +/- 2.1% vs. 30 +/- 1.2%, P < 0.05, respectively), DAI, intestinal tissue damage, and MPO elevation compared with untreated WT DSS control mice (P < 0.05, respectively). These findings suggest that complement plays a role in the development of DSS-induced colitis and that blockade of the complement system might be useful for the acute phase of IBD treatment. C1INH, however, leads to an amelioration of DSS-induced colitis via a mechanism that does not involve the inhibition of complement or contact system activation but does result in significant suppression of leukocyte infiltration. Topics: Animals; Colitis; Colon; Complement C1 Inhibitor Protein; Complement C3; Dextran Sulfate; Disease Models, Animal; Inflammatory Bowel Diseases; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Receptor, Bradykinin B2; Time Factors | 2010 |
Contribution of bone marrow-derived cells to the pro-inflammatory effects of protease-activated receptor-2 in colitis.
Our aim was to determine the contribution of proteinase-activated receptor-2 (PAR(2))-expressing bone marrow-derived cells on the development of colonic inflammation.. Chimeric mice were generated by injecting bone marrow cells from wildtype (PAR (2) (+/+) ) or PAR(2) knockout mice (PAR (2) (-/-) ) into irradiated PAR (2) (+/+) or PAR (2) (-/-) mice.. Colitis was induced by giving 2.5% dextran sodium sulfate (DSS) solution for 7 days or by a single intracolonic administration of trinitrobenzene sulphonic acid (TNBS, 2 mg dissolved in 40% ethanol).. Seven days after the induction of colitis, bowel thickness, inflammatory parameters [myeloperoxidase (MPO) activity, macroscopic/microscopic damage scores], and leukocyte trafficking (visualized via intravital microscopy) were assessed.. Total deficiency of PAR(2) resulted in a marked reduction in severity of both TNBS and DSS induced colitis as assessed by MPO activity, macroscopic damage, bowel thickness, and leukocyte adherence. Colitis was attenuated in all chimeric lines in which there was loss of PAR(2) in the host, non-bone marrow-derived tissue, independent of the status of PAR expression by bone marrow-derived cells. Interestingly, TNBS colitis was attenuated in PAR (2) (+/+) chimeric mice with PAR (2) (-/-) derived bone marrow but these animals were not protected from DSS colitis.. Expression of PAR(2) by host-derived tissues plays a dominant role in regulating colonic inflammation. PAR(2) expression by bone marrow-derived cells appears to play a role in TNBS colitis but not in DSS induced injury. Topics: Animals; Bone Marrow Cells; Bone Marrow Transplantation; Chimera; Colitis; Colon; Dextran Sulfate; Inflammation; Leukocytes; Mice; Mice, Knockout; Peroxidase; Receptor, PAR-2; Trinitrobenzenesulfonic Acid | 2010 |
Effect of low molecular weight heparin rectal suppository on experimental ulcerative colitis in mice.
The objective of this study was to investigate the effect and possible mechanism of rectally administered low molecular weight heparin (LMWH) on experimental ulcerative colitis. LMWH rectal suppository was prepared and its efficacy was studied by macroscopical and histological scoring systems as well as myeloperoxidase activity. Serum levels, including tumor necrosis factor-α (TNFα), interleukin-6 (IL-6) and a link factor of blood coagulation and inflammation factor Xa (FXa) were assayed by enzyme-linked immunosorbent assay. The expression of Musashi-1 (as an intestinal stem cell marker) in the colons was assessed by immunohistochemical analysis. The results showed that LMWH rectal suppository significantly decreased serum levels of TNF-α, IL-6 as well as FXa, while increased the expression of Musashi-1 in colon compared with acetic acid induced ulcerative colitis model group. All these preliminary results indicate LMWH rectal suppository is promising for treatment of ulcerative colitis. Topics: Administration, Rectal; Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colitis, Ulcerative; Colon; Cytokines; Factor Xa; Female; Heparin, Low-Molecular-Weight; Interleukin-6; Male; Mice; Peroxidase; Polyethylene Glycols; Suppositories; Tumor Necrosis Factor-alpha | 2010 |
Intestinal anti-inflammatory activity of esculetin and 4-methylesculetin in the trinitrobenzenesulphonic acid model of rat colitis.
Coumarins comprise a broad class of phenolic compounds that influences the formation and scavenging of reactive oxygen species and the processes involving free radical-mediated injury. In light of the antioxidant and anti-inflammatory properties of esculetin and 4-methylesculetin, the aim of this study was to investigate the effects of these compounds in an experimental model of rat colitis induced by trinitrobenzenesulphonic acid (TNBS). For this purpose, macroscopic (diarrhoea, extension of lesion, colonic weight/length ratio and damage score) and biochemical parameters (myeloperoxidase, alkaline phosphatase and glutathione) were evaluated. Our results reveal that these compounds, particularly 4-methylesculetin, may be effective for the treatment of intestinal inflammatory bowel disease. In the acute colitis model, esculetin promoted a reduction in the extension of the lesion accompanied by a reduction in the incidence of diarrhoea and restoration of the glutathione content. Similar effects were produced by the administration of 4-methylesculetin, which also inhibited the myeloperoxidase and alkaline phosphatase activities in the acute intestinal inflammatory process and in the model of colitis relapse. The effect of the esculetin and 4-methylesculetin on the inflammatory process may be related to their antioxidant and anti-inflammatory properties, as observed in this study. The evidence for better effects of 4-methylesculetin in comparison to those demonstrated by esculetin in both experimental settings could be attributed to the presence of the methyl group at C-4 of 4-methylesculetin. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Colitis; Disease Models, Animal; Glutathione; Male; Peroxidase; Rats; Rats, Wistar; Scopoletin; Structure-Activity Relationship; Sulfasalazine; Trinitrobenzenesulfonic Acid; Umbelliferones | 2010 |
The role of transient receptor potential vanilloid 1 (TRPV1) receptors in dextran sulfate-induced colitis in mice.
The aim of this study was to investigate the involvement of transient receptor potential vanilloid 1 (TRPV1) receptors in oral dextran sulfate sodium-induced (DSS) colitis using TRPV1 knockout mice and their wild-type C57BL/6 counterparts. DSS (2% or 5%) was administered orally ad libitum for 7 days; the controls received tap water. Animal weight, stool consistency, and blood content were scored every day to calculate the disease activity index (DAI). After sacrificing the mice on day 7, the colons were cut into three equal segments (proximal, intermediate, and distal) for histology, myeloperoxidase (MPO), and cytokine measurements. In the 2% DSS-treated group, the lack of TRPV1 receptors decreased the DAI. Each colon segment of wild-type animals showed more than two-fold increase of MPO activity and more severe histological changes compared to the knockouts. This difference was not observed in case of 5% DSS, when extremely severe inflammation occurred in both groups. IL-1beta production was not altered by the absence of TRPV1. In conclusion, activation of TRPV1 channels enhances the clinical symptoms, histopathological changes, and neutrophil accumulation induced by 2% DSS. Elucidating the modulator role of TRPV1 channels in inflammatory bowel diseases may contribute to the development of novel anti-inflammatory drugs for their therapy. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Inflammatory Bowel Diseases; Interleukin-1beta; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; TRPV Cation Channels | 2010 |
Expression of interleukin 6 in brain and colon of rats with TNBS-induced colitis.
To characterise expression of interleukin 6 (IL-6), a potent proinflammatory cytokine, in the occurrence and development of inflammatory bowel disease (IBD) and investigate its effect on neuroimmunomodulation and immune homeostasis regulation.. In this study, rats with colitis induced by trinitrobenzene sulfonic acid (TNBS) were sacrificed on days 3, 7, 14, 21 and 28 after induction. In the controls, the TNBS was just replaced by equivalent amount of phosphate buffered solution (PBS, 0.01 mol/L). IL-6 mRNA expression in brain and colon tissues in each phase was evaluated by real-time reverse transcription-polymerase chain reaction, and cellular localisation and protein level of IL-6 was determined by immunohistochemistry.. At day 7, mRNA expression of IL-6 was significantly higher in the colon and brain of IBD rats than that of the controls. The protein level was also significantly higher in colon, hypothalamus and cerebral cortex of IBD rats compared with the controls. So there are similar temporal trends in IL-6 mRNA expression and protein levels in all positions with a persistent increase to a peak at day 7, followed by a decline and gradual return to normal levels.. These results revealed that changes in IL-6 expression in brain and colon tissues occur in different phases of IBD. Therefore, we propose that the nerve centre regulates and controls the occurrence and development of IBD via IL-6. Topics: Animals; Base Sequence; Brain; Colitis; Colon; Disease Models, Animal; DNA Primers; Female; Gene Expression; Humans; Inflammatory Bowel Diseases; Interleukin-6; Neuroimmunomodulation; Peroxidase; Rats; Rats, Wistar; RNA, Messenger; Trinitrobenzenesulfonic Acid | 2010 |
Anti-inflammatory effect of enzymatic hydrolysate of corn gluten in an experimental model of colitis.
Intestinal bacteria are thought to be involved in the initiation and perpetuation of inflammatory bowel diseases. Prebiotics (non-digestable dietary carbohydrate) have beneficial properties that alter the intestinal flora and contain glutamine-rich protein. Glutamine significantly decreases indices of inflammation. In this study, an enzymatic hydrolysate of corn gluten (EHCG) was administered by gavage to Sprague-Dawley rats fed an elemental diet to determine whether EHCG can ameliorate experi- mental colitis.. Colitis was induced by intrarectal administration of 2,4,6-trinitrobenzene sulfonic acid after 10 days' daily oral administration of EHCG at 100 and 300 mg/kg. Macroscopic damage was assessed using a scoring system. The mucosa homogenate was sonicated and myeloperoxidase activity and histamine levels measured.. Treatment with EHCG significantly decreased the severity of injury and reduced myeloperoxidase activity and histamine levels in the distal colon mucosa.. EHCG may have therapeutic benefit as a supplement in enteral nutrition for patients with inflammatory bowel diseases. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon, Descending; Dietary Supplements; Disease Models, Animal; Dose-Response Relationship, Drug; Food, Formulated; Glutens; Histamine; Intestinal Mucosa; Male; Peroxidase; Protein Hydrolysates; Rats; Rats, Sprague-Dawley; Seeds; Severity of Illness Index; Trinitrobenzenesulfonic Acid; Zea mays | 2010 |
Amelioration of dextran sulfate sodium-induced colitis by neuropeptide Y antisense oligodeoxynucleotide.
Neuropeptide Y (NPY) from enteric neurons has been shown to play an important role in immune and inflammatory responses. The purpose of the present study was to investigate the effects of NPY antisense oligodeoxynucleotides (ODNs) on an experimental model of ulcerative colitis (UC).. NPY antisense ODNs were administered in experimental colitis induced by dextran sulfate sodium (DSS). The disease activity index (DAI) and histological score were observed. The tumor necrosis factor (TNF)-alpha and NPY levels were measured by enzyme-linked immunosorbent assay. Phosphorylated Akt (p-Akt) expression was determined by immunohistochemical staining. Activated nuclear factor (NF)-kappaB was assessed by western blot analysis. Myeloperoxidase (MPO) activity was determined by using MPO assay kit.. A significant improvement was observed in DAI and histological score in rats with NPY antisense ODNs, and the increase in NPY and TNF-alpha levels, MPO activity, and the expression p-Akt and p-NF-kappaB in rats with DSS-induced colitis was significantly reduced following the administration of NPY antisense ODNs.. The administration of NPY antisense ODNs leads to an amelioration of DSS-induced colitis, suggesting that NPY plays an important role in modulating inflammation in colitis, and NPY antisense ODNs may be a useful therapeutic approach to the treatment of UC. Topics: Animals; Colitis; Dextran Sulfate; Fluorescein-5-isothiocyanate; Intestinal Mucosa; Male; Neuropeptide Y; Oligodeoxyribonucleotides; Peroxidase; Phosphatidylinositol 3-Kinases; Phosphorylation; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Signal Transduction; Transcription Factor RelA; Tumor Necrosis Factor-alpha | 2010 |
CXCR4 antagonist AMD3100 attenuates colonic damage in mice with experimental colitis.
To investigate the effects of the chemokine stromal cell-derived factor-1 (CXCL12) receptor (CXCR4) antagonist AMD3100 on colonic inflammation and epithelial barrier in dextran sulfate sodium (DSS)-induced colitis in mice.. Experimental colitis was induced by administration of 5% DSS for 7 d, and assays performed on intestinal segments from the ileocecal valve to the anus. Colonic morphology was examined by hematoxylin and eosin staining. Colonic cytokines were determined by enzyme-linked immunosorbent assay. Myeloperoxidase (MPO) activity (indicator of inflammatory infiltration) was observed spectrophotometrically. Gut permeability was assessed by mucosal-to-serosal clearance of fluorescein isothiocyanate-conjugated dextran 4000 (FD4) in everted gut sacs. The apoptosis of colonic epithelium was assessed by Hoechst-33342 staining. To further elucidate the role of CXCR4 in colonic inflammation, we also investigated the effect of AMD3100 on migration and cytokine production of isolated peripheral blood mononuclear cells (PBMCs).. DSS-induced colitis was characterized by morphologic changes, as well as increased colonic cytokines, inflammatory infiltration, epithelial apoptosis, and intestinal permeability in mice. In AMD3100-treated mice, epithelial destruction, inflammatory infiltration, and submucosal edema were markedly reduced; colonic tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) levels, as well as MPO activity were significantly decreased. Increased intestinal permeability in DSS-treated mice was significantly reduced by AMD3100. The number of apoptotic cells in colitis mice was markedly increased after DSS administration, and decreased when treated with the CXCR4 antagonist AMD3100. In pre-activated PBMCs, CXCL12 stimulation significantly increased the migration of PBMCs, and was inhibited by AMD3100. Moderately increased TNF-alpha, IL-6, and IFN-gamma from CXCL12-treated PBMCs were also reduced by AMD3100.. The CXCR4 antagonist AMD3100 exerts therapeutic effects on experimental colitis by inhibiting colonic inflammation and enhancing epithelial barrier integrity. Topics: Animals; Apoptosis; Benzylamines; Cell Movement; Colitis; Colon; Cyclams; Cytokines; Dextran Sulfate; Female; Heterocyclic Compounds; In Vitro Techniques; Inflammation Mediators; Leukocytes, Mononuclear; Mice; Mice, Inbred BALB C; Permeability; Peroxidase; Receptors, CXCR4 | 2010 |
The effects of Delta-tetrahydrocannabinol and cannabidiol alone and in combination on damage, inflammation and in vitro motility disturbances in rat colitis.
Cannabis is taken as self-medication by patients with inflammatory bowel disease for symptomatic relief. Cannabinoid receptor agonists decrease inflammation in animal models of colitis, but their effects on the disturbed motility is not known. (-)-Cannabidiol (CBD) has been shown to interact with Delta(9)-tetrahydrocannabinol (THC) in behavioural studies, but it remains to be established if these cannabinoids interact in vivo in inflammatory disorders. Therefore the effects of CBD and THC alone and in combination were investigated in a model of colitis.. The 2,4,6-trinitrobenzene sulphonic acid (TNBS) model of acute colitis in rats was used to assess damage, inflammation (myeloperoxidase activity) and in vitro colonic motility. Sulphasalazine was used as an active control drug.. Sulphasalazine, THC and CBD proved beneficial in this model of colitis with the dose-response relationship for the phytocannabinoids showing a bell-shaped pattern on the majority of parameters (optimal THC and CBD dose, 10 mg.kg(-1)). THC was the most effective drug. The effects of these phytocannabinoids were additive, and CBD increased some effects of an ineffective THC dose to the level of an effective one. THC alone and in combination with CBD protected cholinergic nerves whereas sulphasalazine did not.. In this model of colitis, THC and CBD not only reduced inflammation but also lowered the occurrence of functional disturbances. Moreover the combination of CBD and THC could be beneficial therapeutically, via additive or potentiating effects. Topics: Animals; Cannabidiol; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Dronabinol; Drug Therapy, Combination; Gastrointestinal Motility; In Vitro Techniques; Inflammation; Male; Peroxidase; Rats; Rats, Wistar; Sulfasalazine; Trinitrobenzenesulfonic Acid | 2010 |
Soybean and fish oil mixture increases IL-10, protects against DNA damage and decreases colonic inflammation in rats with dextran sulfate sodium (DSS) colitis.
It was investigated whether dietary polyunsaturated fatty acids (PUFA) could influence colonic injury, tissue DNA damage, cytokines and myeloperoxidase activity (MPO) and plasma corticosterone in DSS-induced colitis rats. Male weaning Wistar rats were fed for 47 days with an AIN-93 diet with control (C), fish (F) or a mixture of fish and soybean oil (SF). The colitis was induced from day 36 until day 42 by 3% DSS in drinking water. On day 48, blood samples were collected for corticosterone determination. The distal colon was excised for histological analysis and to quantify the cytokine (IL-4, IL-10 and INF-gamma), MPO and DNA damage. The disease activity index (DAI) was recorded daily during colitis induction. The DAI, MPO, histological analyses showed decreases only in the SF group compared with the C group. IL-10 was increased and DNA damage was reduced in the groups F and SF, and an inverse correlation between these variables was found. There were no differences in corticosterone, IFN-gamma and IL-4 levels. Soybean and fish oil mixture may be effective in improving colonic injury and DNA damage, and it could be an important complementary therapy in UC to reduce the use of anti-inflammatory drugs and prevent colorectal cancer. Topics: Animals; Colitis; Cytokines; Dextran Sulfate; DNA Damage; Fish Oils; Interleukin-10; Male; Peroxidase; Protective Agents; Rats; Rats, Wistar; Soybean Oil | 2010 |
Glial-derived neurotrophic factor regulates intestinal epithelial barrier function and inflammation and is therapeutic for murine colitis.
Although enteric glial cells (EGCs) have been demonstrated to play a key role in maintaining intestinal epithelial barrier integrity, it is not known how EGCs regulate this integrity. We therefore hypothesized that glial-derived neurotrophic factor (GDNF) produced by EGCs might be involved in this regulation. Here we investigated the role of GDNF in regulating epithelial barrier function in vivo. Recombinant adenoviral vectors encoding GDNF (Ad-GDNF) were administered intracolonically in experimental colitis induced by dextran sulphate sodium (DSS). The disease activity index (DAI) and histological score were measured. Epithelial permeability was assayed using Evans blue dye. The anti-apoptotic potency of GDNF in vivo was evaluated. The expression of tumour necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and myeloperoxidase (MPO) activity were measured by ELISA assay and/or RT-PCR. The expression of ZO-1, Akt, caspase-3, and NF-kappaB p65 was analysed by western blot assay. Our results showed that GDNF resulted in a significant reduction in enhanced permeability, inhibited MPO activity, IL-1beta and TNF-alpha expression, and increased ZO-1 and Akt expression. Moreover, GDNF strongly prevented apoptosis in vivo and significantly ameliorated experimental colitis. Our findings indicate that GDNF participates directly in restoring epithelial barrier function in vivo via reduction of increased epithelial permeability and inhibition of mucosal inflammatory response, and is efficacious in DSS-induced colitis. These findings support the notion that EGCs are able to regulate intestinal epithelial barrier integrity indirectly via their release of GDNF in vivo. GDNF is namely an important mediator of the cross-talk between EGCs and mucosal epithelial cells. GDNF may be a useful therapeutic approach to the treatment of inflammatory bowel disease. Topics: Adenoviridae; Animals; Apoptosis; Colitis; Colon; Disease Models, Animal; Drug Evaluation, Preclinical; Female; Genetic Therapy; Genetic Vectors; Glial Cell Line-Derived Neurotrophic Factor; Inflammation Mediators; Intestinal Absorption; Intestinal Mucosa; Membrane Proteins; Mice; Mice, Inbred BALB C; NF-kappa B; Permeability; Peroxidase; Phosphatidylinositol 3-Kinases; Phosphoproteins; Signal Transduction; Zonula Occludens-1 Protein | 2010 |
Preventive oral treatment with resveratrol pro-prodrugs drastically reduce colon inflammation in rodents.
There is no pharmaceutical or definitive surgical cure for inflammatory bowel diseases (IBDs). The naturally occurring polyphenol resveratrol exerts anti-inflammatory properties. However, its rapid metabolism diminishes its effectiveness in the colon. The design of prodrugs to targeting active molecules to the colon provides an opportunity for therapy of IBDs. Herein we explore the efficacy of different resveratrol prodrugs and pro-prodrugs to ameliorate colon inflammation in the murine dextran sulfate sodium (DSS) model. Mice fed with a very low dose (equivalent to 10 mg for a 70 kg-person) of either resveratrol-3-O-(6'-O-butanoyl)-β-D-glucopyranoside (6) or resveratrol-3-O-(6'-O-octanoyl)-β-D-glucopyranoside (7) did not develop colitis symptoms and improved 6-fold the disease activity index (DAI) compared to resveratrol. Our results indicate that these pro-prodrugs exerted a dual effect: (1) they prevented the rapid metabolism of resveratrol and delivered higher quantities of resveratrol to the colon and (2) they reduced mucosal barrier imbalance and prevented diarrhea, which consequently facilitated the action of the delivered resveratrol in the colon mucosa. Topics: Acute-Phase Proteins; Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Cell Line; Colitis; Colon; Cytokines; Dextran Sulfate; Diarrhea; Dinoprostone; Feces; Gastrointestinal Transit; Glucosides; Humans; Intestinal Absorption; Intestinal Mucosa; Mice; Mice, Inbred C57BL; Peroxidase; Prodrugs; Resveratrol; Stereoisomerism; Stilbenes; Structure-Activity Relationship | 2010 |
The importance of oxygen free radicals in the etiopathogenesis of diversion colitis in rats.
Quantify the levels of oxidative DNA damage of epithelial colon cells comparing segments with and without fecal stream.. Sixty Wistar rats were subjected to deviation of fecal stream by proximal colostomy and a distal mucosal fistula. Animals were divided into three experimental groups that were sacrificed 6, 12 and 24 weeks after surgery. In each experimental group, five animals underwent laparotomy without intestinal deviation (sham subgroup). The diagnosis of colitis was made by histopathological analysis and the inflammatory activity index by graduated scale. The neutrophil infiltration was determined by myeloperoxidase tissue levels and the intensity of oxidative DNA damage by comet assay. The Mann-Withney and Student t test were used to compare the results among experimental subgroups and the Kruskal-Wallis test for variance analysis, adopting a significance level of 5% (p<0.05).. Colon segments without fecal stream was shown higher histological inflammatory score of the colon wall after 12 and 24 weeks (p=0.001) that increased with the time of diversion (p=0.01). The activity of myeloperoxidase in segments without fecal stream decreased with the time (p=0.001). Oxidative DNA damage levels were significantly higher in the segments without fecal stream, (p=0.0001), independent of time of colon diversion, and increase with the time (p=0.0007).. Colon segments without fecal stream showed high levels of oxidative DNA damage related to histological alterations observed in diversion colitis. The levels of oxidative DNA damage in segments devoid of the fecal stream increase with the time of intestinal exclusion. Topics: Animals; Colitis; Disease Models, Animal; DNA Damage; Feces; Free Radicals; Gastrointestinal Transit; Intestinal Mucosa; Male; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Wistar; Statistics, Nonparametric | 2010 |
Enteral diets enriched with medium-chain triglycerides and N-3 fatty acids prevent chemically induced experimental colitis in rats.
The specific purpose of this study was to evaluate the significant effects of medium-chain triglycerides (MCTs) and N-3 fatty acids on chemically induced experimental colitis induced by 2,4,6-trinitrobenzene sulphonic acid (TNBS) in rats. Male Wistar rats were fed liquid diets enriched with N-6 fatty acid (control diets), N-3 fatty acid (MCT- diets), and N-3 fatty acid and MCT (MCT+ diets) for 2 weeks and then were given an intracolonic injection of TNBS. Serum and tissue samples were collected 5 days after ethanol or TNBS enema. The severity of colitis was evaluated pathologically, and tissue myeloperoxidase activity was measured in colonic tissues. Furthermore, protein levels for inflammatory cytokines and a chemokine were assessed by an enzyme-linked immunosorbent assay in colonic tissues. Induction of proinflammatory cytokines tumor necrosis factor-α and interleukin-1β in the colon by TNBS enema was markedly attenuated by the MCT+ diet among the 3 diets studied. Furthermore, the induction of chemokines macrophage inflammatory protein-2 and monocyte chemotactic protein-1 also was blunted significantly in animals fed the MCT+ diets. As a result, MPO activities in the colonic tissue also were blunted significantly in animals fed the MCT+ diets compared with those fed the control diets or the MCT- diets. Furthermore, the MCT+ diet improved chemically induced colitis significantly among the 3 diets studied. Diets enriched with both MCTs and N-3 fatty acids may be effective for the therapy of inflammatory bowel disease as antiinflammatory immunomodulating nutrients. Topics: Animal Feed; Animals; Body Weight; Chemokines; Colitis; Colon; Disease Models, Animal; Endotoxemia; Endotoxins; Enema; Enteral Nutrition; Fatty Acids, Omega-3; Male; Peroxidase; Rats; Rats, Wistar; Triglycerides; Trinitrobenzenesulfonic Acid | 2010 |
Dietary polydextrose prevents inflammatory bowel disease in trinitrobenzenesulfonic acid model of rat colitis.
Inflammatory bowel disease (IBD) is a multifactorial intestinal disorder that involves interactions among the immune system, genetic susceptibility, and environmental factors, especially the bacterial flora. Polydextrose, a polysaccharide constituted by 90% nondigestible and nonabsorbable soluble fibers, has several physiological effects consistent with those of dietary fibers, including proliferation of colon microflora. Because sulfasalazine presents serious side effects through long-term use at high doses, the aim of the present study was to evaluate the preventative effect of polydextrose on trinitrobenzenesulfonic acid-induced intestinal inflammation and its effects on the intestinal anti-inflammatory activity of sulfasalazine. Results indicated that polydextrose and its association with sulfasalazine present an anti-inflammatory effect that reduces myeloperoxidase activity, counteracts glutathione content, and promotes reductions in lesion extension and colonic weight/length ratio. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Drug Interactions; Gastrointestinal Agents; Glucans; Glutathione; Inflammatory Bowel Diseases; Male; Organ Size; Oxidative Stress; Peroxidase; Prebiotics; Random Allocation; Rats; Rats, Wistar; Severity of Illness Index; Sulfasalazine; Trinitrobenzenesulfonic Acid | 2010 |
Tetrandrine ameliorates dextran-sulfate-sodium-induced colitis in mice through inhibition of nuclear factor -kappaB activation.
Activation of nuclear factor (NF)-kappaB has been shown to play a critical role in the pathogenesis of ulcerative colitis (UC), and tetrandrine, a bisbenzylisoquinoline alkaloid isolated from the Chinese herb Radix Stephania tetrandra, has been demonstrated to be a potent inhibitor of NF-kappaB activation. The purpose of the study was to investigate effects of tetrandrine on experimental model of UC.. Tetrandrine was administered in experimental colitis induced by dextran sulfate sodium (DSS). The disease activity index (DAI) and histological score were observed. NF-kappaB DNA binding activity was assessed by electrophoretic mobility shift assay. The expression of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta were measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay.. A significant improvement was observed in DAI and histological score in mice with tetrandrine, and the increase in NF-kappaB DNA binding activity, myeloperoxidase activity, IL-1beta, and TNF-alpha in mice with DSS-induced colitis was significantly reduced following administration of tetrandrine.. The administration of tetrandrine leads to an amelioration of DSS-induced colitis, suggesting administration of tetrandrine may provide a therapeutic approach for UC. Topics: Animals; Benzylisoquinolines; Colitis; Dextran Sulfate; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Immunosuppressive Agents; Interleukin-1beta; Mice; Mice, Inbred BALB C; NF-kappa B; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tumor Necrosis Factor-alpha | 2009 |
G protein-coupled receptor kinase 6 controls post-inflammatory visceral hyperalgesia.
Post-inflammatory pain is a poorly understood phenomenon. G protein-coupled receptors are involved in regulating pain signaling in the context of inflammation. G protein-coupled receptor kinases (GRK) modulate signaling through these receptors. We investigated whether GRK6 contributes to post-inflammatory visceral hyperalgesia. Colitis was induced in female mice by 1% dextran sodium sulphate in drinking water for 7 days. Disease score, colon length, and colonic cytokines were determined. On day 49, when animals had recovered from colitis, we induced visceral pain by intracolonic capsaicin instillation. Behavioral responses to capsaicin were monitored for 20 min. Referred hyperalgesia was measured using von Frey hairs. Spinal cord c-Fos was visualized by immunohistochemistry. In contrast to our earlier observations in male GRK6-/- and wild type (WT) mice, we did not detect differences in the course of colitis or in expression of colonic cytokines between female GRK6-/- and WT mice. After recovery from colitis, capsaicin-induced behavioral pain responses and spinal cord c-Fos expression were more pronounced in female GRK6-/- than WT mice. Naive GRK6-/- and WT animals did not differ in pain and c-Fos responses to capsaicin. Capsaicin-induced referred hyperalgesia post-colitis was increased in GRK6-/- compared to WT mice. However, referred hyperalgesia post-colitis was not affected by ablation of GRK6. Furthermore, in vitro IL-1beta sensitized the capsaicin receptor TRPV1 and this process was inhibited by over-expression of GRK6. We describe the novel concept that GRK6 inhibits post-inflammatory visceral hyperalgesia but does not contribute to visceral pain in naive animals. We propose that GRK6 regulates inflammation-induced sensitization of TRPV1. Topics: Analysis of Variance; Animals; Blotting, Western; Capsaicin; Cell Line; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Female; G-Protein-Coupled Receptor Kinases; Hyperalgesia; Inflammation; Mice; Mice, Inbred C57BL; Pain; Pain Measurement; Pain Threshold; Peroxidase; Proto-Oncogene Proteins c-fos; Visceral Afferents | 2009 |
Reducing small intestinal permeability attenuates colitis in the IL10 gene-deficient mouse.
Defects in the small intestinal epithelial barrier have been associated with inflammatory bowel disease but their role in the causation of disease is still a matter of debate. In some models of disease increased permeability appears to be a very early event. The interleukin 10 (IL10) gene-deficient mouse spontaneously develops colitis after 12 weeks of age. These mice have been shown to have increased small intestinal permeability that appears early in life. Furthermore, the development of colitis is dependent upon luminal agents, as animals do not develop disease if raised under germ-free conditions.. To determine if the elevated small bowel permeability can be prevented, and if by doing so colonic disease is prevented or attenuated.. IL10 gene-deficient (IL10(-)/(-)) mice) were treated with AT-1001 (a zonulin peptide inhibitor), a small peptide previously demonstrated to reduce small intestinal permeability. Small intestinal permeability was measured, in vivo, weekly from 4 to 17 weeks of age. Colonic disease was assessed at 8 weeks in Ussing chambers, and at 17 weeks of age inflammatory cytokines and myeloperoxidase were measured in the colon. Colonic permeability and histology were also endpoints.. Treated animals showed a marked reduction in small intestinal permeability. Average area under the lactulose/mannitol time curve: 5.36 (SE 0.08) in controls vs 3.97 (SE 0.07) in the high-dose AT-1001 group, p<0.05. At 8 weeks of age there was a significant reduction of colonic mucosal permeability and increased electrical resistance. By 17 weeks of age, secretion of tumour necrosis factor alpha (TNFalpha) from a colonic explant was significantly lower in the treated group (25.33 (SE 4.30) pg/mg vs 106.93 (SE 17.51) pg/ml in controls, p<0.01). All other markers also demonstrated a clear reduction of colitis in the treated animals. Additional experiments were performed which demonstrated that AT-1001 was functionally active only in the small intestine.. This work suggests that increased intestinal permeability may be an important aetiological event in the development of colitis in IL10(-)/(-) mice. Topics: Animals; Cholera Toxin; Colitis; Colon; Cytokines; Diffusion Chambers, Culture; Haptoglobins; Interleukin-10; Intestinal Absorption; Intestine, Small; Mice; Mice, Knockout; Oligopeptides; Permeability; Peroxidase; Protein Precursors | 2009 |
Distinct cytokine patterns identified from multiplex profiles of murine DSS and TNBS-induced colitis.
The cytokine network in inflammatory bowel disease (IBD) is a complex, dynamic system that plays an important role in regulating mucosal innate and adaptive immune responses. While several studies have been done to evaluate immunomodulatory profiles in murine IBD, they have been limited to a relatively small number of cytokines that do not take into account its dependency of the interplay of multiple factors, and therefore the diagnostic potential of their cytokine profiles have been inconclusive.. A novel approach of comprehensive serum multiplex cytokine profiling with biometric immunosandwich ELISA's was used to describe the modulation of 16 Th1, Th2, Th17 cytokines and chemokines in both acute and chronic murine models of DSS and TNBS-induced colitis. Advanced multivariate discriminant functional analyses (DFA) was used to identify statistically interrelated sets of variables with the most significant power to discriminate among the groups. Profiles of multiple cytokines seen systemically were also validated locally in colonic mucosa using Western blot analysis and fluorescent immunohistochemistry.. Distinctive disease-specific cytokine profiles were identified with significant correlations to disease activity and duration of disease. TNBS colitis exhibits heightened Th1-Th17 response (increased IL-12 and IL-17) as the disease becomes chronic. In contrast, DSS colitis switches from a Th1-Th17-mediated acute inflammation (increased TNF-alpha, IL6, IL-17, and KC) to a predominant Th2-mediated inflammatory response (increase in IL-4 and IL-10 and concomitant decrease in TNF-alpha, IL6, IL-17, and KC) in the chronic state. Moreover, DFA identified discriminatory cytokine profiles that can be sufficiently used to distinguish unaffected controls from diseases, and one disease type from another. IL-6 and IL-12 stratified gender-associated disease activity in chronic colitis.. Our studies provide insight into disease immunopathogenesis and illustrate the significant potential of utilizing multiplex cytokine profiles and bioinformatics as diagnostic tools in IBD. Topics: Animals; Blotting, Western; Chronic Disease; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Disease Progression; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Female; Immunohistochemistry; Intestinal Mucosa; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Peroxidase; Trinitrobenzenesulfonic Acid | 2009 |
Attenuation of colitis injury in rats using Garcinia cambogia extract.
Inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis are chronic enteropathies that probably result from a dysregulated mucosal immune response. These pathologies are characterized by oxidative and nitrosative stress, leukocyte infiltration and up-regulation of pro-inflammatory substances. Current IBD treatment presents limitations in both efficacy and safety that stimulated the search for new active compounds. Garcinia cambogia extract has attracted interest due to its pharmacological properties, including gastroprotective effects. In this study, the antiinflammatory activity of a garcinia extract was assessed in TNBS-induced colitis rats. The results obtained revealed that garcinia administration to colitic rats significantly improved the macroscopic damage and caused substantial reductions in increases in MPO activity, COX-2 and iNOS expression. In addition, garcinia extract treatment was able to reduce PGE(2) and IL-1beta colonic levels. These antiinflammatory actions could be related to a reduction in DNA damage in isolated colonocytes, observed with the comet assay. Finally, garcinia extract caused neither mortality nor toxicity signals after oral administration. As such, the antiinflammatory effects provided by the Garcinia cambogia extract result in an improvement of several parameters analysed in experimental colitis and could provide a source for the search for new antiinflammatory compounds useful in IBD treatment. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Dinoprostone; Disease Models, Animal; DNA Damage; Female; Garcinia cambogia; Inflammation Mediators; Male; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2009 |
Curcumin attenuates inflammation through inhibition of TLR-4 receptor in experimental colitis.
Curcumin, an active ingredient of Curcumin longa mediates its anti-inflammatory effects through inhibition of NFkB. Several pathways including toll-like receptors (TLR) induce NFkB leading to inflammation. In this study, we investigated the effects of curcumin on the expression of TLR-4 and MyD88, the upstream signaling pathway in experimental colitis induced in the Sprague-Dawley male rats by intra-rectal administration of trinitrobenzenesulfonic acid (TNBS). The animals which received TNBS were divided into two groups: Group 1, received aqueous suspension of curcumin (100 mg/Kg body weight) 2 h prior to inducing colitis, and the treatment was repeated every day for 5 days, and Group 2 and non-colitis (Group 3) animals received phosphate buffered saline (PBS) in a similar fashion. Non-colitis animals (Group 4) received curcumin and served as controls. Animals were sacrificed on day 5 post-TNBS by cervical dislocation, colon was taken out, and cleaned with PBS. Levels of TLR-4, MyD88, and NFkB proteins were measured using ECL Western blot analysis, and TLR-4 mRNA by a competitive RT-PCR method. Colitis was confirmed histologically by measuring myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels in the colonic tissues. TNBS-induced increase in the level of MPO activity and MDA concentrations was reversed by curcumin treatment, whereas the same dose of curcumin did not affect their levels in the non-colitis animals. Increases in the levels of TLR-4, MyD88, and NFkB proteins in inflamed tissue were also suppressed significantly by curcumin treatment. The level of TLR-4 mRNA remained unchanged in the colitis animals. These findings demonstrate that signaling pathway of curcumin-induced inhibition of inflammation involves TLR-4 and MyD88, and therefore may serve as an important therapeutic target in IBD. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Curcumin; Male; Models, Animal; Myeloid Differentiation Factor 88; Peroxidase; Rats; Rats, Sprague-Dawley; RNA, Messenger; Signal Transduction; Toll-Like Receptor 4 | 2009 |
Helminth antigen-based strategy to ameliorate inflammation in an experimental model of colitis.
Inflammatory bowel disease (IBD) is the most common and serious chronic inflammatory condition of the gut. Among the distinct T helper (Th) cell subsets, a Th1 type response is associated predominantly with Crohn's disease (CD) while helminth infections generate a strong Th2 type response. IBD is most prevalent in developed countries but rare in countries where infections with helminths are common. Thus, it has been hypothesized that infection with helminth infection influence the development of CD and recent clinical and experimental studies suggest strongly a beneficial role of helminth infection in IBD. In the present study we examined the effects of rectal submucosal administration of helminth antigens on subsequent experimental colitis. Mice were treated with Trichinella spiralis antigens prior to the induction of dinitrobenzenesulphonic acid (DNBS)-induced colitis and were killed 3 days post-DNBS to assess colonic damage macroscopically, histologically and by myeloperoxidase (MPO) activity, inducible nitric oxide synthase (iNOS) and cytokine levels. Previous treatment with T. spiralis antigens reduced the severity of colitis significantly, as assessed macroscopically and histologically, and reduced the mortality rate. This benefit was correlated with a down-regulation of MPO activity, interleukin (IL)-1beta production and iNOS expression and an up-regulation of IL-13 and transforming growth factor-beta production in colon. These results clearly show a beneficial role of local treatment with helminth antigens for experimental colitis and prompt consideration of helminth antigen-based therapy for IBD instead of infection with live parasites. Topics: Animals; Antigens, Helminth; Colitis; Colon; Dinitrofluorobenzene; Injections; Interleukin-13; Interleukin-1beta; Male; Mice; Mice, Inbred C57BL; Models, Animal; Nitric Oxide Synthase Type II; Peroxidase; Rectum; Transforming Growth Factor beta; Trichinella spiralis; Trichinellosis; Vaccination | 2009 |
Effect of N-acetylcysteine on the murine model of colitis induced by dextran sodium sulfate through up-regulating PON1 activity.
Reactive oxygen species (ROS) are increased in inflammatory bowel disease (IBD) and have been implicated as mediators of intestinal inflammation. We investigated the hypothesis that N-acetylcysteine (NAC) as a glutathione (GSH) precursor attenuates disease progression in a murine dextran sodium sulfate (DSS)-induced colitis model. A colitis model was induced by adding 5% DSS into the drinking water for 7 days. BALB/c mice were injiciatur enema with saline, 5-ASA, N-acetylcysteine, respectively, and free drinking water as control group. DSS-treated mice developed severe colitis as shown by bloody diarrhea, weight loss, and pathologic involvement. Colon lengths were significantly decreased in DSS-treated mice with decreased GSH activity too (P < 0.01). ROS in the colon, the level of interleukin 1 beta (IL-1 beta) in colonic mucosa, serum tumor necrosis factor a (TNF-alpha), MPO, and MDA were significantly increased in DSS-treated animals (P < 0.01), with decreased PON1 activity (P < 0.01). However, NAC significantly decreased colonic MPO activity, ROS, TNF-alpha and IL-1 beta levels and increased PON1 activity and GSH concentration. Moreover, NAC attenuated the macroscopic colonic damage and the histopathologic changes-induced by DSS while similar to 5-ASA group. These results suggest that NAC may be effective in the treatment of colitis through its up-regulating PON1 and scavenging oxygen-derived free radicals. Topics: Acetylcysteine; Animals; Antioxidants; Aryldialkylphosphatase; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Down-Regulation; Glutathione; Interleukin-1beta; Male; Mice; Mice, Inbred BALB C; Oxidative Stress; Peroxidase; Reactive Oxygen Species; Severity of Illness Index; Tumor Necrosis Factor-alpha; Up-Regulation | 2009 |
Role of serotonin in intestinal inflammation: knockout of serotonin reuptake transporter exacerbates 2,4,6-trinitrobenzene sulfonic acid colitis in mice.
Serotonin (5-HT) regulates peristaltic and secretory reflexes in the gut. The serotonin reuptake transporter (SERT; SLC6A4), which inactivates 5-HT, is expressed in the intestinal mucosa and the enteric nervous system. Stool water content is increased and colonic motility is irregular in mice with a targeted deletion of SERT. We tested the hypotheses that 5-HT plays a role in regulating intestinal inflammation and that the potentiation of serotonergic signaling that results from SERT deletion is proinflammatory. Rectal installation of 2,4,6-trinitrobenzene sulfonic acid (TNBS) was used to induce an immune-mediated colitis, which was compared in SERT knockout mice and littermate controls. Intestinal myeloperoxidase and histamine levels were significantly increased, whereas the survival rate and state of health were significantly decreased in TNBS-treated mice that lacked SERT. Deletion of SERT thus increases the severity of TNBS colitis. These data suggest that 5-HT and its SERT-mediated termination play roles in intestinal immune/inflammatory responses in mice. Topics: Animals; Colitis; Colon; Gastrointestinal Motility; Histamine; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Rectum; Serotonin; Serotonin Plasma Membrane Transport Proteins; Trinitrobenzenesulfonic Acid | 2009 |
Therapeutic effects of four strains of probiotics on experimental colitis in mice.
To investigate the therapeutic effects of four strains of probiotics (E. feacalis, L. acidophilus, C. butyricum and B. adolescentis) on dextran sulphate sodium (DSS)-induced experimental colitis in Balb/c mice.. Eighty Balb/c mice were randomly divided into 8 groups. Weight-loss, fecal character, fecal occult blood and hematochezia were recorded daily. Disease activity index (DAI) scores were also evaluated everyday. Length of colon was measured and histological scores were evaluated on the 13th day. Myeloperoxidase (MPO) activity was detected. Interleukin-1 (IL-1) and IL-4 expression was detected by ELISA and RT-PCR.. The four strains of probiotics relieved the inflammatory condition of DSS-induced experimental colitis in mice. Weight loss was slowed down in all probiotics-treated mice. Even weight gain was observed by the end of probiotics treatment. The DAI and histological scores of probiotics-treated mice were lower than those of mice in the control group (1.9 +/- 0.2 vs 8.6 +/- 0.4, P < 0.05 for E. faecalis). The length of colon of probiotics-treated mice was longer than that of mice in the control group (10.3 +/- 0.34 vs 8.65 +/- 0.77, P < 0.05 for E. faecalis). The four strains of probiotics decreased the MP activity and the IL-1 expression, but increased the IL-4 expression. E. faecalis had a better effect on DSS-induced experimental colitis in mice than the other three strains.. The four strains of probiotics have beneficial effects on experimental colitis in mice. E. faecalis has a better effect on DSS-induced experimental colitis in mice than the other three strains. Supplement of probiotics provides a new therapy for UC. Topics: Animals; Body Weight; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Disease Progression; Female; Interleukin-1beta; Interleukin-4; Male; Mice; Mice, Inbred BALB C; Peroxidase; Probiotics; Random Allocation | 2009 |
Peripheral anti-nociceptive effect of nociceptin/orphanin FQ in inflammation and stress-induced colonic hyperalgesia in rats.
Nociceptin/orphanin FQ (N/OFQ) and its NOP receptors are present in the central nervous system and in the periphery playing important roles in the modulation of gastrointestinal functions and pain. The aim of this study was to investigate the role of central and peripheral N/OFQ-NOP receptor system in the nociceptive response to colorectal distension (CRD) in basal condition and in two models of gut hypersensitivity triggered by both inflammation and stress. Male Wistar rats were tested in basal and in post-inflammatory conditions, i.e., 5 days after IC TNBS instillation (80 mg/Kg) and received N/OFQ (2 nmol/Kg IP), UFP-101 (a selective NOP receptor antagonist, 10 nmol/Kg IP), N/OFQ+UFP-101, N/OFQ (0.5 nmol/rat ICV) or vehicle. Female rats were tested in basal and after partial restraint stress receiving the same pharmacological treatment. CRD was performed using barostat and abdominal contractions were recorded by electromyography. In basal condition, N/OFQ, ICV and IP injected, did not modify basal visceral sensitivity. Both in TNBS and stress-induced hyperalgesia, IP but not ICV injection of N/OFQ significantly decreased the number of abdominal contractions. Peripheral injection of UFP-101 antagonized N/OFQ effect. Moreover, in post-inflammatory colitis, UFP-101, injected alone, exacerbated visceral hyperalgesia to CRD compared with vehicle. These findings indicate that in rats, N/OFQ, only peripherally injected, reduces visceral hypersensitivity triggered by inflammation or stress without affecting basal sensitivity. N/OFQ visceral anti-hyperalgesic effect involves peripheral NOP receptors. In a post-inflammatory, but not in an acute stress colitis model, N/OFQergic system is endogenously activated. Topics: Analgesics; Animals; Colitis; Colon; Disease Models, Animal; Drug Administration Routes; Drug Interactions; Electromyography; Gene Expression Regulation; Hyperalgesia; Nociceptin; Nociceptin Receptor; Opioid Peptides; Peroxidase; Physical Stimulation; Rats; Rats, Wistar; Receptors, Opioid; Restraint, Physical; Sensory Thresholds; Stress, Psychological; Trinitrobenzenesulfonic Acid | 2009 |
Depot-specific alterations to insulin signaling in mesenteric adipose tissue during intestinal inflammatory response.
Current knowledge suggests that adipose tissue is an active organ, participating in intestinal and mesenteric disease. Additionally, adipose tissue surrounds the lymph nodes and has special properties, acting as a paracrine regulator of adjacent lymphoid tissues. These adipose tissue depots can express and secrete numerous cytokines, known as adipocytokines, which then modify the action of insulin in adipose tissue itself. Using a well-accepted model of intestinal inflammation, we studied insulin signaling in mesenteric adipose tissue (MAT) and in perinodal mesenteric adipose tissue (PAT). Our results showed that the action of insulin is modified during the intestinal inflammatory response in these adipose tissue depots. MAT became resistant to insulin signaling, as evaluated by the IRS/AKT pathway, in the inflammation. This resistant status was associated with high JNK activity and the presence of infiltrating macrophages. Conversely, the adipose tissue that involves the mesenteric lymph nodes acquired greater sensitivity to insulin signaling via IRS/AKT, probably via up-regulation of IRS during experimental colitis. We demonstrated experimentally the existence of site-specific adaptive alterations in two mesenteric adipose tissue depots to the intestinal inflammatory response, probably resulting in alterations in free fatty acids and other secretory products supplied by the adjacent tissues that could act as inflammatory modulator substances. Topics: Adipose Tissue; Animals; Colitis; Insulin; Insulin Receptor Substrate Proteins; Intestinal Mucosa; Intestines; Male; Mesentery; Peroxidase; Phosphorylation; Rats; Rats, Wistar; Signal Transduction; Trinitrobenzenesulfonic Acid; Tyrosine | 2009 |
Mitogen-activated protein kinase pathways contribute to hypercontractility and increased Ca2+ sensitization in murine experimental colitis.
Inflammatory bowel disease (IBD) is associated with intestinal smooth muscle dysfunction. Many smooth muscle contractile events are associated with alterations in Ca(2+)-sensitizing pathways. The aim of the present study was to assess the effect of colitis on Ca(2+) sensitization and the signaling pathways responsible for contractile dysfunction in murine experimental colitis. Colitis was induced in BALB/c mice by providing 5% dextran sulfate sodium (DSS) in drinking water for 7 days. Contractile responses of colonic circular smooth muscle strips to 118 mM K(+) and carbachol (CCh) were assessed. DSS induced a T(H)2 colitis [increased interleukin (IL)-4 and IL-6] with no changes in T(H)1 cytokines. Animals exposed to DSS had increased CCh-induced contraction (3.5-fold) and CCh-induced Ca(2+)-sensitization (2.2-fold) responses in intact and alpha-toxin permeabilized colonic smooth muscle, respectively. The contributions of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) to CCh-induced contractions were significantly increased during colitis. Ca(2+)-independent contraction induced by microcystin was potentiated (1.5-fold) in mice with colitis. ERK and p38MAPK (but not Rho-associated kinase) contributed to this potentiation. ERK1/2 and p38MAPK expression were increased in the muscularis propria of colonic tissue from both DSS-treated mice and patients with IBD (ulcerative colitis >> Crohn's disease). Murine T(H)2 colitis resulted in colonic smooth muscle hypercontractility with increased Ca(2+) sensitization. Both ERK and p38MAPK pathways contributed to this contractile dysfunction, and expression of these molecules was altered in patients with IBD. Topics: Animals; Calcium; Carbachol; Colitis; Colon; Cytokines; Dextran Sulfate; Extracellular Signal-Regulated MAP Kinases; Female; MAP Kinase Signaling System; Mice; Mice, Inbred BALB C; Microcystins; Muscle Contraction; p38 Mitogen-Activated Protein Kinases; Peroxidase; Th2 Cells | 2009 |
Colonic bacterial translocation as a possible factor in stress-worsening experimental stroke outcome.
Stress is known to be one of the risk factors of stroke, but only a few experimental studies have examined the possible mechanisms by which prior stress may affect stroke outcome. In stroke patients, infections impede neurological recovery and increase morbidity as well as mortality. We previously reported that stress induces a bacterial translocation and that prior immobilization stress worsens experimental stroke outcome through mechanisms that involve inflammatory mediators such as release of proinflammatory cytokines and enzyme activation. We now investigate whether bacterial translocation from the intestinal flora of rats with stress before experimental ischemia is involved in stroke outcome. We used an experimental paradigm consisting of exposure of Fischer rats to repeated immobilization sessions before permanent middle cerebral artery occlusion (MCAO). The presence of bacteria and the levels and expression of different mediators involved in the bacterial translocation were analyzed. Our results indicate that stress before stroke is related to the presence of bacteria in different organs (mesenteric nodes, spleen, liver, and lung) after MCAO and increases inflammatory colonic parameters (such as cyclooxygenase-2, inducible nitric oxide synthase, and myeloperoxidase), but decreases colonic immunoglobulin A, and these results are correlated with colonic inflammation and bacterial translocation. Understanding the implication of bacterial translocation during stress-induced stroke worsening is of great potential clinical relevance, given the high incidence of infections after severe stroke and their main role in mortality and morbidity in stroke patients. Topics: Animals; Anti-Bacterial Agents; Bacterial Translocation; Colitis; Colon; Corticosterone; Cyclooxygenase 2; Disease Models, Animal; Immunoglobulin A; Infarction, Middle Cerebral Artery; Lung; Lymph Nodes; Male; Nitric Oxide Synthase Type II; Penicillin G; Permeability; Peroxidase; Rats; Rats, Inbred F344; Restraint, Physical; Risk Factors; Spleen; Stress, Psychological; Stroke | 2009 |
Effects of the endothelin-converting enzyme inhibitor SM-19712 in a mouse model of dextran sodium sulfate-induced colitis.
Ingestion by mice of dextran sodium sulfate (DSS) induces colonic vasoconstriction and inflammation, with some of the effects potentially mediated by the vasoconstrictor endothelin-1 (ET-1).. In this study, mice given 5% 40 kD DSS for 5-6 days had elevated colonic immunostaining for ET-1 and platelet endothelial cell adhesion molecule-1 (PECAM-1). Increased ET-1 can induce microvascular constriction; however, the increase in PECAM-1 is consistent with angiogenesis that could decrease flow resistance.. Our measurements of intestinal blood flow, via infused microspheres, suggests that these 2 factors may offset each other, with only a nonsignificant tendency for a DSS-induced decrease in flow. Daily administration of the endothelin converting enzyme inhibitor SM-19712 (15 mg/kg) attenuated DSS-induced increases in colonic immunostaining of ET-1 and PECAM-1.. SM-19712 attenuated histologic signs of tissue injury and inflammation induced by DSS, and decreased the extent of loose stools and fecal blood. However, the inhibitor did not significantly decrease DSS-induced colon shortening or tissue levels of myeloperoxidase (an indicator of neutrophil infiltration). Topics: Animals; Aspartic Acid Endopeptidases; Blood Pressure; Body Weight; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Endothelin-1; Endothelin-Converting Enzymes; Enzyme Inhibitors; Ileum; Metalloendopeptidases; Mice; Mice, Inbred C57BL; Organ Size; Peroxidase; Platelet Endothelial Cell Adhesion Molecule-1; Sulfonamides; Sulfonylurea Compounds; Vasoconstriction | 2009 |
Oral treatment with genistein reduces the expression of molecular and biochemical markers of inflammation in a rat model of chronic TNBS-induced colitis.
Inflammatory bowel disease (IBD) in humans has a high incidence in Europe and the USA, whereas in East Asia, incidence has been historically low. The risk of IBD appears to increase in Asian immigrants adopting western lifestyles, suggesting a strong link of environmental/dietary factors in the development of IBD. Exposure to high levels of isoflavones such as genistein (Gen) in traditional East Asian diets has been associated with a decreased risk of developing breast cancer and may also be beneficial for the prevention of IBD.. In this study, the effect of orally administered genistein on the inflammatory response in the TNBS-induced chronic colitis rat model was investigated.. Eighteen male Wistar rats, aged 12 weeks, were randomized to one of three groups (n = 6). Two groups received a 2,4,6-trinitrobenzenesulfonic acid (TNBS) enema, then were treated daily by oral gavage with either Gen (100 mg/kg b.w.) or vehicle, for 14 days. The last group served as a control group, not receiving the TNBS enema. At the end of the 14 days, animals were killed and tissues collected. Molecular and biochemical inflammatory markers in the colon, specifically cyclooxygenase-2 (COX-2) and myeloperoxidase (MPO), were analyzed. In addition, to assess the efficacy of Gen treatment, relative wet weights of the accessory sexual organs, specifically prostate and the seminal vesicle, were compared between the groups treated or not with Gen.. Wet weights of both prostates and seminal vesicles were significantly (P < 0.01) reduced upon Gen administration. In the colon, expression of COX-2 mRNA and protein was reduced (P < 0.05) in the Gen treatment group, as compared to the control group, whereas there was no significant inhibitory effect of Gen on the expression of proliferating cell nuclear antigen. In Gen treated animals colon wet weight was not altered, however a decrease in MPO activity (P < 0.01) was seen.. These results may provide evidence that oral administration of Gen exerts beneficial anti-inflammatory effects in a rodent model of TNBS-induced chronic colitis. While the sample size of this study was small, it nevertheless might encourage the realization of larger blinded randomized controlled studies for the proof of concept. Topics: Administration, Oral; Animals; Colitis; Colon; Cyclooxygenase 2; Disease Models, Animal; Genistein; Genitalia, Male; Inflammation; Male; Organ Size; Peroxidase; Proliferating Cell Nuclear Antigen; Random Allocation; Rats; Rats, Wistar; RNA, Messenger; Trinitrobenzenesulfonic Acid | 2009 |
Effects of verbascoside biotechnologically produced by Syringa vulgaris plant cell cultures in a rodent model of colitis.
The aim of the present study was to examine the effects of verbascoside (VB) in rats subjected to experimental colitis. Colitis was induced in rats by intracolonic instillation of 2,4 dinitrobenzene sulfonic acid (DNBS; 25 mg/rat). VB was administered daily per os (0.2 and 2 mg/kg) 4 days after DNBS administration in the colon. Treatment with VB significantly (P < 0.01) reduced macroscopic damage score, loss of body weight, myeloperoxidase activity and thiobarbituric acid-reactant substances. Moreover, the intensity of the positive staining for tumor necrosis factor-alpha, interleukin-1beta, intercellular adhesion molecule-1, P-selectin, inducible nitric oxide synthase, and poly(ADP ribose) was also significantly (P < 0.01) reduced by VB treatment. Therefore, VB treatment significantly (P < 0.01) reduced the degree of NF-kappaB p65 and activation of the pro-active form metalloproteinase (MMP)-2 and pro-MMP-9 activity. The results of this study suggested that VB functions as an intracellular radical scavenger and so reduces the microscopic and macroscopic signs of colitis in the rat. Therefore, administration of VB may be beneficial for the treatment of inflammatory bowel disease. Topics: Animals; Antioxidants; Body Weight; Cells, Cultured; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Precursors; Gelatinases; Glucosides; Male; Matrix Metalloproteinase 9; Peroxidase; Phenols; Rats; Rats, Sprague-Dawley; Syringa; Thiobarbituric Acid Reactive Substances; Transcription Factor RelA | 2009 |
Lactobacillus fermentum CECT 5716 prevents and reverts intestinal damage on TNBS-induced colitis in mice.
Probiotics attenuate gut inflammation when administered before experimental colitis, but data on their effect after colitis induction are scarce. We aimed to evaluate the effects of Lactobacillus fermentum CECT 5716 on gut injury when administered either before or after trinitrobencene sulfonic acid (TNBS) colitis in Balb/c mice.. In a preventive study, probiotic or vehicle was administered for 2 weeks before colitis. Then mice were allocated to: probiotic + TNBS, probiotic + sham, vehicle + TNBS, or vehicle + sham, and sacrificed 72 hours later. In a therapeutic study, mice were allocated into the same groups as before. Probiotic or vehicle were administered for 3 weeks. Mice were sacrificed at weeks 1, 2, and 3 after TNBS. Histological score, myeloperoxidase activity, and eicosanoid and cytokine production in colonic explant cultures were measured. Immunohistochemistry for nitrotyrosine and MyD88 was also performed.. In the preventive study, colitis was milder with probiotic than with vehicle (P = 0.041). This was associated with increased PGE(2), IL-2, and IL-4 production, as well as attenuated nitrotyrosine staining in the former. In the therapeutic study, histological score at week 1 post-TNBS was higher in probiotic than in vehicle fed mice (P = 0.018). However, at weeks 2 and 3 the histological score was significantly lower-with decreased IL-6 production and increased MyD88 staining-in mice receiving the probiotic.. Pretreatment with L. fermentum CECT 5716 attenuates TNBS colitis, an effect that seems to be due to its antioxidant abilities. When administered after TNBS, this probiotic is also effective in accelerating colitis recovery, and this is associated with an enhanced Toll-like receptor function. Topics: Animals; Colitis; Colony Count, Microbial; Cytokines; Disease Models, Animal; Eicosanoids; Immunoenzyme Techniques; Intestinal Mucosa; Limosilactobacillus fermentum; Mice; Mice, Inbred BALB C; Myeloid Differentiation Factor 88; Peroxidase; Probiotics; Trinitrobenzenesulfonic Acid; Tyrosine | 2009 |
Increased CYP4B1 mRNA is associated with the inhibition of dextran sulfate sodium-induced colitis by caffeic acid in mice.
Susceptibility to inflammatory bowel diseases depends upon interactions between the genetics of the individual and induction of chronic mucosal inflammation. We hypothesized that administration of dietary phenolics, caffeic acid and rutin, would suppress upregulation of inflammatory markers and intestinal damage in a mouse model of colitis. Colitis was induced in C3H/ HeOuJ mice (8 weeks old, 6 male/6 female per treatment) with 1.25% dextran sulfate sodium (DSS) for 6 d in their drinking water. Rutin (1.0 mmol (524 mg)/kg in diet), caffeic acid (1.0 mmol (179 mg)/kg in diet), and hypoxoside extract (15 mg/d, an anticolitic phenolic control) were fed to the mice for 7 d before and during DSS treatment, as well as without DSS treatment. Body weight loss was prevented by rutin and caffeic acid during DSS treatment. Colon lengths in mice fed caffeic acid and hypoxoside during DSS treatment were similar to DSS-negative control. Food intake was improved and myeloperoxidase (MPO) was decreased with each phenolic treatment in DSS-treated mice compared with DSS treatment alone. Colonic mRNA expression of IL-17 and iNOS were inhibited when IL-4 was increased by each phenolic treatment combined with DSS, whereas CYP4B1 mRNA was increased only by caffeic acid in DSS-treated mice, compared with DSS treatment alone. Colonic and cecal histopathology scores of DSS-treated mice were significantly more severe (P < 0.01) than in mice fed caffeic acid before and during DSS treatment, based on mucosal height, necrosis, edema, erosion, and inflammatory cell infiltration. Although both rutin and caffeic acid suppressed the expression of selected inflammatory markers, only caffeic acid protected against DSS-induced colitis, in association with normalization of CYP4B1 expression. The inhibition of DSS-induced colitic pathology by caffeic acid was mediated by mechanisms in addition to anti-inflammatory effects that deserve further study. Topics: Alkynes; Animals; Antioxidants; Aryl Hydrocarbon Hydroxylases; Body Weight; Caffeic Acids; Colitis; Colon; Dextran Sulfate; Eating; Female; Gene Expression Regulation, Enzymologic; Glucosides; Humans; Inflammatory Bowel Diseases; Interleukin-17; Interleukin-4; Male; Mice; Nitric Oxide Synthase Type II; Organ Size; Peroxidase; RNA, Messenger; Rutin; Time Factors | 2009 |
3,3'-diindolylmethane attenuates colonic inflammation and tumorigenesis in mice.
3,3-Diindolylmethane (DIM) is a major in vivo product of acid-catalyzed oligomerization of indole-3-carbinol (I3C) derived from Brassica food plants. Although DIM is known as a chemopreventive and chemotherapeutic phytochemical, the effects of DIM on inflammation in vivo are still unknown. In the present study we investigated the antiinflammatory effects of DIM on experimental colitis and colitis-associated colorectal carcinogenesis.. To determine if DIM has an antiinflammatory effect in vivo, we examined the therapeutic effects of DIM in dextran sodium sulfate (DSS)-induced experimental colitis and colitis-associated colon carcinogenesis induced by azoxymethane (AOM)/DSS in BALB/c mice.. Treatment with DIM significantly attenuated loss of body weight, shortening of the colon, and severe clinical signs in a colitis model. This was associated with a remarkable amelioration of the disruption of the colonic architecture and a significant reduction in colonic myeloperoxidase activity and production of prostaglandin E(2), nitric oxide, and proinflammatory cytokines. Further, DIM administration dramatically decreased the number of colon tumors in AOM/DSS mice.. These results suggest that DIM-mediated antiinflammatory action at colorectal sites may be therapeutic in the setting of inflammatory bowel disease and colitis-associated colon cancer. Topics: Animals; Anticarcinogenic Agents; Azoxymethane; Body Weight; Carcinogens; Cell Transformation, Neoplastic; Colitis; Colonic Neoplasms; Dextran Sulfate; Dinoprostone; Disease Models, Animal; Indoles; Mice; Mice, Inbred BALB C; NF-kappa B; Nitric Oxide; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Weight Loss | 2009 |
Positive role of CCAAT/enhancer-binding protein homologous protein, a transcription factor involved in the endoplasmic reticulum stress response in the development of colitis.
Although recent reports suggest that the endoplasmic reticulum (ER) stress response is induced in association with the development of inflammatory bowel disease, its role in the pathogenesis of inflammatory bowel disease remains unclear. The CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) is a transcription factor that is involved in the ER stress response, especially ER stress-induced apoptosis. In this study, we found that experimental colitis was ameliorated in CHOP-null mice, suggesting that CHOP exacerbates the development of colitis. The mRNA expression of Mac-1 (CD11b, a positive regulator of macrophage infiltration), Ero-1alpha, and Caspase-11 (a positive regulator of interleukin-1beta production) in the intestine was induced with the development of colitis, and this induction was suppressed in CHOP-null mice. ERO-1alpha is involved in the production of reactive oxygen species (ROS); an increase in ROS production, which is associated with the development of colitis in the intestine, was suppressed in CHOP-null mice. A greater number of apoptotic cells in the intestinal mucosa of wild-type mice were observed to accompany the development of colitis compared with CHOP-null mice, suggesting that up-regulation of CHOP expression exacerbates the development of colitis. Furthermore, this CHOP activity appears to involve various stimulatory mechanisms, such as macrophage infiltration via the induction of Mac-1, ROS production via the induction of ERO-1alpha, interleukin-1beta production via the induction of Caspase-11, and intestinal mucosal cell apoptosis. Topics: Animals; Apoptosis; Caspases; Caspases, Initiator; Colitis; Endoplasmic Reticulum; Immunoblotting; Interleukin-1beta; Intestinal Mucosa; Lipid Peroxidation; Macrophage-1 Antigen; Macrophages; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Oxidative Stress; Peroxidase; Reactive Oxygen Species; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Thiobarbituric Acid Reactive Substances; Transcription Factor CHOP | 2009 |
Sleep deprivation worsens inflammation and delays recovery in a mouse model of colitis.
We recently showed that patients with inflammatory bowel disease (IBD) report significantly more sleep disturbances. To determine whether disrupted sleep can affect the severity of inflammation and the course of IBD, we used an animal model of colonic inflammation to determine the effects of acute and chronic intermittent sleep deprivation on the severity of colonic inflammation and tissue damage in colitis and recovery from this damage.. Acute sleep deprivation (ASD) consisted of 24h of forced locomotor activity in a mechanical wheel rotating at a constant speed. Chronic intermittent sleep deprivation (CISD) consisted of an acute sleep deprivation episode, followed by additional sleep deprivation periods in the wheel for 6h every other day throughout the 10day study period. To induce colitis, mice were given 2% dextran sodium sulfate (DSS) in their daily drinking water for 7days. The development and severity of colitis were monitored by measuring weight loss and tissue myeloperoxidase (MPO) activity daily and colon histology scores 10days after initiation of colitis.. ASD or CISD did not cause colonic inflammation in vehicle-treated mice. Changes in daily body weight, tissue MPO levels and colon histopathology score were similar between mice that were sleep deprived and controls. Daily DSS ingestion caused colitis in mice. ASD worsened colonic inflammation: tissue MPO levels in ASD/DSS-treated mice were significantly higher than in DSS-treated mice that were not sleep deprived. However, the worsening of colonic inflammation by ASD was not enough to exacerbate clinical manifestations of colitis such as weight loss. In contrast, the deleterious effects of CISD were severe enough to cause worsening of histological and clinical manifestations of colitis. The deleterious effects of sleep deprivation on severity of colitis appeared to be due to both increased colonic inflammation and a decrease in the ability of mice to recover from DSS-induced colonic injury.. Both acute and chronic intermittent sleep deprivation exacerbate colonic inflammation. Thus, sleep deprivation could be an environmental trigger that predisposes IBD patients to develop flare ups and a more severe disease course. These results provide a scientific rationale to conduct an interventional trial to determine whether improvement in sleep patterns will prevent IBD flare ups, modify the disease course, and improve quality of life. Topics: Acute Disease; Animals; Body Weight; Chronic Disease; Colitis; Colon; Dextran Sulfate; Diarrhea; Disease Models, Animal; Gastrointestinal Hemorrhage; Male; Mice; Mice, Inbred C57BL; Organ Size; Peroxidase; Rectal Diseases; Sleep Deprivation | 2009 |
Synthesis, kinetic studies and pharmacological evaluation of mutual azo prodrugs of 5-aminosalicylic acid for colon-specific drug delivery in inflammatory bowel disease.
Colon-specific mutual azo prodrugs of 5-aminosalicylic acid with essential amino acids were synthesized for the management of inflammatory bowel disease. The structures were confirmed by elemental and spectral analyses. 85-88% release of 5-aminosalicylic acid was achieved in rat fecal matter with half-lives ranging from 140 to 160 min, following first order kinetics. The prodrugs exhibited comparable ameliorating effect as that of sulfasalazine on trinitrobenzenesulfonic acid-induced experimental colitis in rats with a better safety profile. Topics: Aminosalicylic Acids; Animals; Arthritis; Colitis; Colon; Female; Inflammatory Bowel Diseases; Male; Peroxidase; Prodrugs; Rats; Rats, Wistar; Ulcer | 2009 |
Effects of the ACE2 inhibitor GL1001 on acute dextran sodium sulfate-induced colitis in mice.
Angiotensin-converting enzyme 2 (ACE2) is expressed in gastrointestinal tissue. Previous studies of GL1001, a potent and selective ACE2 inhibitor, have revealed anti-inflammatory activity in the mouse digestive tract. We hypothesized that GL1001 might also produce beneficial effects in a mouse DSS model of inflammatory bowel disease.. Female mice were used for study.. Animals were treated for 5 days with 5% DSS in the drinking water to induce colitis. For the following 9 days, animals were treated twice daily with GL1001 (30, 100, 300 mg/kg, s.c.), sulfasalazine (150 mg/kg, p.o.), or vehicle.. Throughout the experiment, body weight, rectal prolapse, stool consistency, and fecal occult blood were monitored. At termination, colon length, histopathology, and myeloperoxidase activity were assessed.. High-dose GL1001 ameliorated DSS-induced disease activity, including rectal prolapse and intestinal bleeding. The most robust effect of GL1001 was observed 48-96 h post DSS treatment and was comparable in magnitude to that of sulfasalazine. Colon pathology and myeloperoxidase activity were also markedly attenuated by high-dose GL1001 treatment, with the most profound effects observed in the distal segment.. The findings support the previously observed anti-inflammatory effects of ACE2 inhibition in gastrointestinal tissue and suggest that GL1001 may have therapeutic utility for inflammatory bowel disease. Topics: Angiotensin-Converting Enzyme 2; Angiotensin-Converting Enzyme Inhibitors; Animals; Body Weight; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Female; Humans; Imidazoles; Inflammatory Bowel Diseases; Leucine; Mice; Mice, Inbred BALB C; Peptidyl-Dipeptidase A; Peroxidase; Random Allocation | 2009 |
Temporal and spatial analysis of clinical and molecular parameters in dextran sodium sulfate induced colitis.
Inflammatory bowel diseases (IBD), including mainly ulcerative colitis (UC) and Crohn's disease (CD), are inflammatory disorders of the gastrointestinal tract caused by an interplay of genetic and environmental factors. Murine colitis model induced by Dextran Sulfate Sodium (DSS) is an animal model of IBD that is commonly used to address the pathogenesis of IBD as well as to test efficacy of therapies. In this study we systematically analyzed clinical parameters, histological changes, intestinal barrier properties and cytokine profile during the colitic and recovery phase.. C57BL/6 mice were administered with 3.5% of DSS in drinking water for various times. Clinical and histological features were determined using standard criteria. Myeloperoxidase (MPO) activity, transepithelial permeability and proinflammatory mediators were determined in whole colon or proximal and distal parts of colon.. As expected after administration of DSS, mice manifest loss of body weight, shortening of colon length and bloody feces. Histological manifestations included shortening and loss of crypts, infiltration of lymphocytes and neutrophil, symptoms attenuated after DSS withdrawal. The MPO value, as inflammation indicator, also increases significantly at all periods of DSS treatment, and even after DSS withdrawal, it still held at very high levels. Trans-mucosal permeability increased during DSS treatment, but recovered to almost control level after DSS withdrawal. The production of proinflammatory mediators by colonic mucosa were enhanced during DSS treatment, and then recovered to pre-treated level after DSS withdrawal. Finally, enhanced expression of proinflammatory mediators also revealed a different profile feature in proximal and distal parts of the colon.. Experimental colitis induced by DSS is a good animal model to study the mechanisms underlying the pathogenesis and intervention against IBD, especially UC. Topics: Animals; Body Weight; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Inflammation; Mice; Mice, Inbred C57BL; Models, Biological; Permeability; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; Time Factors | 2009 |
Balsalazine decreases intestinal mucosal permeability of dextran sulfate sodium-induced colitis in mice.
To investigate the effect of balsalazine treatment on intestinal mucosal permeability in dextran sulfate sodium (DSS)-induced colitis and to determine the mechanism of the balsalazine-induced changes.. Experimental colitis was induced in C57BL/6J mice by the administration of 5% DSS. Balsalazine was administered intragastrically at doses of 42, 141, and 423 mg/kg. The disease activity index (DAI) score was evaluated and colon tissue was collected for the assessment of histological changes. The amount of malondialdehyde (MDA) in the colon was determined, along with the activity of myeloperoxidase (MPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Mucosa from the small intestine was collected to determine the levels of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma. The mucosa was ultrastructurally examined with transmission electron microscopy and intestinal permeability was assayed using Evans blue.. Balsalazine was found to reduce the DAI score and the histological index (HI) score, decrease the MDA content and the activity of MPO, and increase the activity of SOD and GSH-Px in colitis mice. At the same time, balsalazine ameliorated microvillus and tight junction structure, resulting in a decrease in the amount of Evans blue permeating into the intestinal wall and the levels of TNF-alpha and IFN-gamma in colitis mice.. In colitis mice, the anti-colitis effect of balsalazine results in a decrease in intestinal mucosal permeability. The mechanism of this effect is partly associated with balsalazine's antioxidative and anti-inflammatory effects.Acta Pharmacologica Sinica (2009) 30: 987-993; doi: 10.1038/aps.2009.77. Topics: Animals; Colitis; Dextran Sulfate; Gastrointestinal Agents; Glutathione Peroxidase; Interferon-gamma; Intestinal Absorption; Intestinal Mucosa; Malondialdehyde; Mesalamine; Mice; Mice, Inbred C57BL; Peroxidase; Phenylhydrazines; Superoxide Dismutase; Tumor Necrosis Factor-alpha | 2009 |
Reduction of colonic inflammation in HLA-B27 transgenic rats by feeding Marie Ménard apples, rich in polyphenols.
Inflammatory bowel diseases (IBD) are immunomediated ailments affecting millions of individuals. Although diet is regarded as an important factor influencing IBD, there are no accepted dietary recommendations presently available. We administered 7.6 % lyophilised apples obtained from two cultivars (Golden Delicious and Marie Ménard, low and high in polyphenols, respectively) to HLA-B27 transgenic rats which develop spontaneous IBD. After 3 months feeding, rats fed Marie Ménard apples had reduced myeloperoxidase activity (3.6 (sem 0.3) v. 2.2 (sem 0.2) U/g tissue; P < 0.05) and reduced cyclo-oxygenase-2 (P < 0.05) and inducible NO synthase gene expression (P < 0.01) in the colon mucosa and significantly less diarrhoea (P < 0.05), compared with control rats. Cell proliferation in the colon mucosa was reduced significantly by feeding Golden Delicious apples, with a borderline effect of Marie Ménard apples. Gene expression profiling of the colon mucosa, analysed using the Whole Rat Genome 4 x 44 K Agilent Arrays, revealed a down-regulation of the pathways of PG synthesis, mitogen-activated protein kinase (MAPK) signalling and TNFalpha-NF-kappaB in Marie Ménard-fed rats. In the stools of the animals of this group we also measured a significant reduction of bacteria of the Bacteriodes fragilis group. In conclusion, the administration of Marie Ménard apples, rich in polyphenols and used at present only in the manufacturing of cider, ameliorates colon inflammation in transgenic rats developing spontaneous intestinal inflammation, suggesting the possible use of these and other apple varieties to control inflammation in IBD patients. Topics: Animals; Bacteria; Colitis; Cyclooxygenase 2; Diet; Feces; Flavonoids; Gene Expression Profiling; Gene Expression Regulation; Genetic Predisposition to Disease; HLA-B27 Antigen; Humans; Intestinal Mucosa; Male; Malus; Nitric Oxide Synthase Type II; Oligonucleotide Array Sequence Analysis; Peroxidase; Phenols; Polyphenols; Rats; Rats, Transgenic; Species Specificity | 2009 |
The effect of sildenafil, a phosphodiesterase-5 inhibitor, on acetic acid-induced colonic inflammation in the rat.
Sildenafil, a selective and potent inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase (PDE)5, has a relaxant effect on the smooth muscle cells of the arterioles supplying the human corpus cavernosum acting via nitric oxide (NO)-dependent mechanism. This study aimed to investigate the possible protective effect of sildenafil citrate on the extent of tissue integrity, oxidant-antioxidant status and neutrophil infiltration to the inflamed organ in a rat model of acetic acid-induced colitis.. Colitis was induced by intrarectal administration of 1 mL of 5% acetic acid to Sprague-Dawley rats (200-250 g; n = 7-8/group). Control rats received an equal volume of saline intrarectally. In treatment groups, the rats were treated with either sildenafil citrate (5 mg/kg/day; subcutaneously) or saline for 3 days. After decapitation, distal colon was weighed and scored macroscopically and microscopically. Tissue samples were used for the measurement of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity, and oxidant production. Trunk blood was collected for the assessment of serum tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta levels.. In the colitis group, the colonic tissue was characterized by lesions, increased lipid peroxidation with a concomitant reduction in GSH content, increased MPO activity and oxidant production. Serum TNF-alpha and IL-1beta levels were higher in the colitis group compared to control values. Sildenafil reversed these inflammatory parameters nearly back to control values.. Sildenafil citrate administration to rats with acetic acid-induced colitis seems to be beneficial via prevention of lipid peroxidation, oxidant generation, cytokine production and neutrophil accumulation. Topics: Acetic Acid; Analysis of Variance; Animals; Colitis; Glutathione; Interleukin-1beta; Luminescence; Malondialdehyde; Microscopy, Electron, Scanning; Peroxidase; Phosphodiesterase Inhibitors; Piperazines; Purines; Rats; Rats, Sprague-Dawley; Sildenafil Citrate; Statistics, Nonparametric; Sulfones; Tumor Necrosis Factor-alpha | 2009 |
The possible mechanisms of Fructus Mume pill in the treatment of colitis induced by 2,4,6-trinitrobenzene sulfonic acid in rats.
Fructus Mume pill (FMP) has been used as a folk remedy for gastrointestinal diseases in China over thousands of years. FMP was approved for the treatment of gastrointestinal diseases in 2001 by the State Food and Drug Administration (SFDA) of China. Although FMP had significant efficacy for treatment of the patients with inflammatory bowel disease (IBD) in the clinic, the mechanism of action is still unclear.. In the present study, the effects and possible mechanism of FMP on colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) were investigated.. Fifty-four SD rats were divided into six groups. Nine rats for each group from three independent experiments were investigated for the effects of FMP.. FMP protected against diarrhea, colon weight increase, colonic accretion, ulceration and myeloperoxidase (MPO) activity elevation. The effects of FMP on recovery of colonic damage and restoration of the normal structures of colorectums were superior to dexamethasone (DEX). FMP promoted the restoration of abnormal cytokine secretion after TNBS treatment. FMP was effective in restoring the balance of intestinal bacteria population from the imbalance of G(+)/G(-) in rats with colitis.. The results indicated that FMP is effective in treatment of colitis in an experimental rat model. The possible mechanisms may be through down-regulation of Th1-polarized immune response and opsonic effect of intestinal commensal bacteria in this model system. Topics: Animals; Body Weight; Colitis; Cytokines; Dexamethasone; Diarrhea; Herbal Medicine; Intestines; Male; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2009 |
Inhibitory effects of Geijigajakyak-Tang on trinitrobenzene sulfonic acid-induced colitis.
Water extract of Geijigajakyak-Tang (GJT) consisting of five crude drugs [dried root of P. lactiflora Peony (Paeoniaceae), dried trunk bark of C. cassia Blume (Lauraceae), seed of Z. jujube var. inermis Mill (Rhamnaceae), fresh root of Z. officinale Rocoe (Zingiberaceae) and dried trunk bark of G. uralensis Fish (Leguminosae)] is a folk medicine used for the treatment of chronic colitis. This study was designed to further elucidate the effect of GJT on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats.. GJT orally given to mice before and after TNBS intoxication, and their clinical and morphological changes, myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels in colon tissues, were evaluated on Day 8 post-TNBS. Furthermore, the effect of six major constituents of individual herbs on ileum smooth muscle contraction and neutrophil chemotaxis was studied.. GJT had a significant anti-inflammatory effect based on clinical and morphologic changes, MPO activity and MDA levels in colon tissues as compared with sham control. GJT and 5 major active constituents of individual herbs, paeoniflorin, cinnamaldehyde, jujuboside A, jujubogenin, and diammonium glycyrhhizinate significantly inhibited neutrophil chemotaxis. GJT significantly inhibited muscle contraction (IC(50); 2.10 +/- 0.11 mg/ml), and 1,8-cineol has the most spasmolytic activity (IC(50); 0.10 +/- 0.03 mg/ml).. GJT has significant anti-inflammatory effects on TNBS-induced colitis via inhibitions of smooth muscle contraction and neutrophil chemotaxis. Topics: Acrolein; Animals; Anti-Inflammatory Agents; Antioxidants; Benzoates; Bridged-Ring Compounds; Chemotaxis; Colitis; Cyclohexanols; Eucalyptol; Female; Glucosides; Glycyrrhizic Acid; Ileum; Lipid Peroxidation; Magnoliopsida; Malondialdehyde; Mice; Mice, Inbred BALB C; Models, Animal; Monoterpenes; Muscle Contraction; Muscle, Smooth; Neutrophils; Parasympatholytics; Peroxidase; Phytotherapy; Plant Extracts; Saponins; Trinitrobenzenesulfonic Acid; Triterpenes | 2009 |
Si-Ni-San, a traditional Chinese prescription, and its active ingredient glycyrrhizin ameliorate experimental colitis through regulating cytokine balance.
Si-Ni-San, a traditional Chinese medicinal formula, exerts an important function in the treatment of inflammatory bowel diseases based upon thousands of years of clinical practice, but the underlying mechanism is still unclear. In this study, we investigated the therapeutic potential of Si-Ni-San and its ingredient glycyrrhizin in trinitrobenzene sulfonic acid (TNBS)-induced experimental colitis in mice, a well-characterized murine model for Crohn's disease. Si-Ni-San and glycyrrhizin significantly ameliorated TNBS-induced colitis with reduced mortality and recovery of body weights. In addition, Si-Ni-San and glycyrrhizin dose-dependently decreased macroscopic inflammation scores, microscopic histological scores, and myeloperoxidase activity. Furthermore, Si-Ni-San and glycyrrhizin caused a decrease in pro-inflammatory cytokines including IFN-gamma, IL-12, TNF-alpha and IL-17 and an increase in regulatory cytokine IL-10 in colon of the mice. It should be noticed the therapeutic effect of Si-Ni-San at 450 mg/kg was much better than that of its contained content of glycyrrhizin at 10 mg/kg. In conclusion, Si-Ni-San and glycyrrhizin significantly ameliorated TNBS-induced colitis in mice through regulating pro- and anti-inflammatory cytokine production. Topics: Animals; Body Weight; Colitis; Colon; Crohn Disease; Cytokines; Diarrhea; Disease Models, Animal; Drugs, Chinese Herbal; Female; Glycyrrhizic Acid; Humans; Medicine, Chinese Traditional; Mice; Mice, Inbred C57BL; Peroxidase; Trinitrobenzenesulfonic Acid | 2009 |
Neuromuscular changes in a rat model of colitis.
Intracolonic administration of Trichinella spiralis larvae in rats causes colitis with features similar to ulcerative colitis, notably with inflammation predominantly limited to the colonic mucosa. Our aim was to characterize the functional and neurochemical changes occurring within the myenteric (MP) and submucosal plexuses (SMP) during T. spiralis-induced colitis. Infected rats had decreased body weight, altered stool consistency and elevated myeloperoxidase activity, 6 and 14 days post-infection (PI). Responses to acetylcholine and KCl in circular muscle strips were reduced in infected tissues, demonstrating an impairment of contractility. In addition, there was a decrease in spontaneous motor activity and reduced sensitivity to the nitric oxide synthase (NOS) inhibitor L-NOArg, corresponding with a significant reduction in NOS immunoreactive neurons in the MP of infected animals. T. spiralis did not alter the total number of myenteric or submucosal neurons. Substance P innervation of submucosal blood vessels was reduced after infection, as were submucosal calretinin and calbindin immunoreactive neurons. No changes in choline acetyltransferase and calcitonin gene-related peptide immunoreactivity were observed. T. spiralis-induced colitis causes profound neuromuscular adaptations. The reduction in NOS neurons appears to underlie changes in motility. Topics: Animals; Calcitonin Gene-Related Peptide; Choline O-Acetyltransferase; Colitis; Colon; Disease Models, Animal; Gastrointestinal Motility; Immunohistochemistry; In Vitro Techniques; Intestinal Mucosa; Intestines; Male; Muscle Contraction; Muscle, Smooth; Myenteric Plexus; Nerve Tissue Proteins; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Sprague-Dawley; Submucous Plexus; Trichinella spiralis; Trichinellosis; Weight Loss | 2008 |
The relevance of kinin B1 receptor upregulation in a mouse model of colitis.
Kinins are implicated in many pathophysiological conditions, and recent evidence has suggested their involvement in colitis. This study assessed the role of the kinin B1 receptors in a mouse model of colitis.. Colitis was induced in mice by 2,4,6-trinitrobenzene sulphonic acid (TNBS), and tissue damage and myeloperoxidase activity were assessed. B1 receptor induction was analysed by organ bath studies, binding assay and reverse transcription PCR.. TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of colon B1 receptor-mediated contraction, with the maximal response observed at 72 h. The upregulation of the B1 receptor at this time point was also confirmed by means of binding studies. B1 receptor mRNA levels were elevated as early as 6 h after colitis induction and remained high for up to 48 h. TNBS-evoked tissue damage and neutrophil influx were reduced by the selective B1 receptor antagonist SSR240612, and in B1 receptor knockout mice. In vivo treatment with inhibitors of protein synthesis, nuclear factor-kappaB activation, inducible nitric oxide synthase (iNOS) or tumour necrosis factor alpha (TNFalpha) significantly reduced B1 receptor agonist-induced contraction. Similar results were observed in iNOS and TNF receptor 1-knockout mice.. These results provide convincing evidence on the role of B1 receptors in the pathogenesis of colitis. Therefore, the blockade of kinin B1 receptors might represent a new therapeutic option for treating inflammatory bowel diseases. Topics: Animals; Colitis; Colon; In Vitro Techniques; Indicators and Reagents; Kallidin; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Receptor, Bradykinin B1; Reverse Transcriptase Polymerase Chain Reaction; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Up-Regulation | 2008 |
Intestinal anti-inflammatory activity of coumarin and 4-hydroxycoumarin in the trinitrobenzenesulphonic acid model of rat colitis.
Coumarins represent an important class of phenolic compounds with multiple biological activities, including inhibition of lipidic peroxidation and neutrophil-dependent anion superoxide generation, anti-inflammatory and immunosuppressor actions. All of these proprieties are essential for that a drug may be used in the treatment of inflammatory bowel disease. The present study examined intestinal anti-inflammatory activity of coumarin and its derivative, the 4-hydroxycoumarin on experimental ulcerative colitis in rats. This was performed in two different experimental settings, i.e. when the colonic mucosa is intact or when the mucosa is in process of recovery after an initial insult. The results obtained revealed that the coumarin and 4-hydroxycoumarin, at doses of 5 and 25 mg/kg, significantly attenuated the colonic damage induced by trinitrobenzenesulphonic acid (TNBS) in both situations, as evidenced macroscopically, microscopically and biochemically. This effect was related to an improvement in the colonic oxidative status, since coumarin and 4-hydroxycoumarin prevented the glutathione depletion that occurred as a consequence of the colonic inflammation. Topics: 4-Hydroxycoumarins; Acute Disease; Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Chronic Disease; Colitis; Colon; Coumarins; Diarrhea; Gastrointestinal Agents; Glutathione; Male; Organ Size; Peroxidase; Rats; Rats, Wistar; Secondary Prevention; Sulfasalazine; Trinitrobenzenesulfonic Acid | 2008 |
A2B adenosine receptor gene deletion attenuates murine colitis.
The A(2B) adenosine receptor (A(2B)AR) is the predominant adenosine receptor expressed in the colonic epithelia. We have previously shown that A(2B)AR mRNA and protein levels are up-regulated during colitis. In this study, we addressed the role of the A(2B)AR in the development of murine colitis and the potential mechanism underlying its effects.. Dextran sodium sulfate (DSS), 2,4,6-trinitrobenzene sulfonic acid (TNBS), and Salmonella typhimurium were used to induce colitis in A(2B)AR-null mice (A(2B)AR(-/-)). Colitis was determined using established clinical and histologic scoring. Keratinocyte-derived chemokine (KC) measurements were performed using an enzyme-linked immunosorbent assay.. Colonic inflammation induced by DSS, TNBS, or S typhimurium was attenuated in A(2B)AR(-/-) compared with their wild-type counterparts. Clinical features, histologic score, and myeloperoxidase activity were significantly decreased in A(2B)AR(-/-) mice. However, A(2B)AR(-/-) showed increased susceptibility to systemic Salmonella infection. Tissue levels of the neutrophil chemokine, KC was decreased in colitic A(2B)AR(-/-) mice. In addition, flagellin-induced KC levels were attenuated in A(2B)AR(-/-) mice. Neutrophil chemotaxis in response to exogenous interleukin-8 was preserved in A(2B)AR(-/-) mice, suggesting intact neutrophil migration in response to appropriate stimuli.. These data demonstrate, for the first time, that the A(2B)AR plays a proinflammatory role in colitis. A(2B) receptor antagonism may be an effective treatment for acute inflammatory intestinal diseases such as acute flare of inflammatory bowel disease. Topics: Animals; Cell Migration Assays, Leukocyte; Chemokine CXCL1; Colitis; Colon; Dextran Sulfate; Disease Susceptibility; Female; Flagellin; Gene Deletion; Inflammation Mediators; Interleukin-8; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; Peroxidase; Receptor, Adenosine A2B; Salmonella Infections; Salmonella typhimurium; Trinitrobenzenesulfonic Acid | 2008 |
Therapeutic potential of two probiotics in inflammatory bowel disease as observed in the trinitrobenzene sulfonic acid model of colitis.
The pathogenesis of inflammatory bowel disease is thought to be a multifactorial process. One of the leading hypotheses is that an imbalance in normal gut flora induces an excessive immune response and contributes to inflammation in the gastrointestinal tract. Administration of probiotic bacteria reduces symptoms in patients suffering from inflammatory bowel diseases, probably via both manipulation of the microflora and stimulation of the intestinal immune system. In the current study the therapeutic potential of two different probiotics-Lactobacillus GG and a mixture of Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium longum (YO-MIX Y 109 FRO 1000)--in a rat model of colitis were evaluated.. Male Wistar rats were administered probiotics for three days simultaneously with colitis induction. Colonic damage was evaluated histologically and biochemically and colonic tissues, as well as fecal samples, were used for bacterial studies using 16S rRNA gene primers.. Probiotics administration reduced the relative amounts of the pathogenic bacteria Aeromonas and Escherichia coli in the colonic tissue. However, whereas both probiotics affected colon morphology, only Lactobacillus GG administration reduced myeloperoxidase activity.. We report the therapeutic rather than preventive potential of two different probiotics in an animal model of colitis. Topics: Animals; Bifidobacterium; Colitis; Disease Models, Animal; Lactobacillus; Male; Peroxidase; Probiotics; Rats; Rats, Wistar; Streptococcus thermophilus; Trinitrobenzenesulfonic Acid | 2008 |
Protective effects of Lactobacillus rhamnosus [corrected] and Bifidobacterium infantis in murine models for colitis do not involve the vagus nerve.
The vagus nerve is an important pathway signaling immune activation of the gastrointestinal tract to the brain. Probiotics are live organisms that may engage signaling pathways of the brain-gut axis to modulate inflammation. The protective effects of Lactobacillus rhamnosus [corrected] (LR) and Bifidobacterium infantis (BI) during intestinal inflammation were studied after subdiaphragmatic vagotomy in acute dextran sulfate sodium (DSS) colitis in BALB/c mice and chronic colitis induced by transfer of CD4(+) CD62L(+) T lymphocytes from BALB/c into SCID mice. LR and BI (1 x 10(9)) were given daily. Clinical score, myeloperoxidase (MPO) levels, and in vivo and in vitro secreted inflammatory cytokine levels were found to be more severe in mice that were vagotomized compared with sham-operated animals. LR in the acute DSS model was effective in decreasing the MPO and cytokine levels in the tissue in sham and vagotomized mice. BI had a strong downregulatory effect on secreted in vitro cytokine levels and had a greater anti-inflammatory effect in vagotomized- compared with sham-operated mice. Both LR and BI retained anti-inflammatory effects in vagotomized mice. In SCID mice, vagotomy did not enhance inflammation, but BI was more effective in vagotomized mice than shams. Taken together, the intact vagus has a protective role in acute DSS-induced colitis in mice but not in the chronic T cell transfer model of colitis. Furthermore, LR and BI do not seem to engage their protective effects via this cholinergic anti-inflammatory pathway, but the results interestingly show that, in the T cell, transfer model vagotomy had a biological effect, since it increased the effectiveness of the BI in downregulation of colonic inflammation. Topics: Acute Disease; Administration, Oral; Animals; Bifidobacterium; Body Weight; CD4-Positive T-Lymphocytes; Chronic Disease; Colitis; Colon; Dextran Sulfate; Interleukin-6; Limosilactobacillus reuteri; Male; Mice; Mice, Inbred BALB C; Mice, SCID; Peroxidase; Probiotics; Spleen; T-Lymphocytes; Tumor Necrosis Factor-alpha; Vagotomy; Vagus Nerve | 2008 |
Effect of different doses of Manuka honey in experimentally induced inflammatory bowel disease in rats.
To evaluate the effect of different doses of Manuka honey in experimentally induced inflammatory bowel disease in rats. Adult Wistar rats of either sex were used (n = 30). Colitis was induced by a single intracolonic administration of TNBS dissolved in 35% ethanol. The rats (n = 30) were divided into five groups (n = 6) and were treated with vehicle (ethanol), TNBS, Manuka honey (5 g/kg, p.o.), Manuka honey (10 g/kg, p.o.) or sulfasalazine (360 mg/kg, p.o.) body weight for 14 days. After completion of treatment, the animals were killed and the following parameters were assessed: morphological score, histological score and different antioxidant parameters.Manuka honey at different doses provided protection against TNBS-induced colonic damage. There was significant protection with Manuka honey 5 g/kg as well as with 10 g/kg body weight compared with the control (p < 0.001). All the treated groups showed reduced colonic inflammation and all the biochemical parameters were significantly reduced compared with the control in the Manuka honey treated groups (p < 0.001). Manuka honey at different doses restored lipid peroxidation as well as improved antioxidant parameters. Morphological and histological scores were significantly reduced in the low dose Manuka honey treated group (p < 0.001). In the inflammatory model of colitis, oral administration of Manuka honey 5 g/kg and Manuka honey 10 g/kg body weight significantly reduced the colonic inflammation. The present study indicates that Manuka honey is efficacious in the TNBS-induced rat colitis model, but these results require further confirmation in human studies. Topics: Analysis of Variance; Animals; Antioxidants; Colitis; Colon; Disease Models, Animal; Glutathione; Honey; Inflammation; Inflammatory Bowel Diseases; Lipid Peroxidation; Male; Peroxidase; Rats; Rats, Wistar; Sulfasalazine; Superoxide Dismutase; Trinitrobenzenesulfonic Acid | 2008 |
Acute and chronic responses associated with adrenomedullin administration in experimental colitis.
Adrenomedullin (AM) is a 52 amino acid peptide and member of the calcitonin gene-related peptide (CGRP) super family. Given that AM has emerged as a potential immuno-regulatory and anti-inflammatory agent in various experimental models, this study has deepened into its possible therapeutic effect in intestinal inflammation analyzing the responses in both acute and chronic (14 and 21 days) phases of TNBS-induced colitis in rats. In the acute model, AM treatment reduced the incidence of diarrhea and the severity of colonic damage, and improved the survival rate at the three doses assayed (50, 100, and 200ng/kg animal). AM administration was able to reduce the early production of TNF-alpha and collaborated to maintaining basal levels of IFN-gamma and IL-10. In the chronic studies the peptide attenuated the extent of the damage with lesser incidence of weight loss and diarrhea (50 and 100ng/kg animal). Cellular neutrophil infiltration, with the subsequent increase in myeloperoxidase (MPO) levels caused by TNBS, was reduced after chronic AM administration. The peptide played a role in the evolution of Th1/Th2 cytokines balance and chronic disease recuperation: levels of proinflammatory TNF-alpha and IFN-gamma decreased and anti-inflammatory IL-10 increased significantly. Cyclooxygenase-2 (COX-2) and nitric oxide synthase (iNOS) protein expression were not modified by AM administration, although a reduction of nitric oxide (NO) production could be detected in the chronic model. These results support a role of AM as an anti-inflammatory factor with beneficial effects in intestinal inflammatory colitis. Topics: Acute Disease; Adrenomedullin; Animals; Anti-Inflammatory Agents; Chronic Disease; Colitis; Colon; Female; Interferon-gamma; Interleukin-10; Male; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2008 |
Piceatannol, a stilbene present in grapes, attenuates dextran sulfate sodium-induced colitis.
Piceatannol (3,5,3',4'-tetrahydroxy-trans-stilbene; PIC) is a polyphenol found in grapes. It is known as a protein kinase inhibitor that modifies multiple cellular targets, exerting immunosuppressive and antitumorigenic activities in several cell lines. The purpose of the present work was to evaluate the anti-inflammatory effect of PIC on dextran sulfate sodium (DSS)-induced colitis. Experimental colitis was induced in BALB/c mice by dissolving 5% DSS in their drinking water for 7 days. PIC (1, 2.5, 5, or 10 mg/kg body weight) was administrated daily per oral route for 7 days. A significant blunting of weight loss and clinical signs was observed in DSS-exposed, PIC-treated mice when compared to vehicle-treated mice. This was associated with a remarkable amelioration of the disruption of the colonic architecture, a significant reduction in colonic myeloperoxidase (MPO) activity, and a decrease in production of inflammatory mediators such as nitric oxide (NO), prostaglandin (PG) E2, and pro-inflammatory cytokines. The present data indicate that further evaluation of the potential of PIC as an agent for the prevention and/or treatment of inflammatory bowel diseases in human clinical studies is warranted. Topics: Animals; Colitis; Colon; Dextran Sulfate; Female; Immunohistochemistry; Inflammation Mediators; Mice; Mice, Inbred BALB C; NF-kappa B; Peroxidase; STAT3 Transcription Factor; Stilbenes; Vitis | 2008 |
Do desipramine [10,11-dihydro-5-[3-(methylamino) propyl]-5H-dibenz[b,f]azepine monohydrochloride] and fluoxetine [N-methyl-3-phenyl-3-[4-(trifluoromethyl)phenoxy]-propan-1-amine] ameliorate the extent of colonic damage induced by acetic acid in rats?
The present study was designed to compare the anti-inflammatory and antioxidant effects of two antidepressant drugs, desipramine [10,11-dihydro-5-[3-(methylamino) propyl]-5H-dibenz-[b,f]azepine monohydrochloride] and fluoxetine [N-methyl-3-phenyl-3-[4-(trifluoromethyl)phenoxy]-propan-1-amine], administered with variable doses, on experimentally induced colitis in rats. Two doses for each drug (10 and 20 mg/kg/day i.p.) were injected in 48 adult male albino rats for 2 weeks after induction of colitis by intracolonic administration of 2 ml of 3% acetic acid. Several parameters, including macroscopic (ulcer score index) and biochemical such as myeloperoxidase (MPO), reduced glutathione (GSH), tumor necrosis factor (TNF)-alpha, and interleukin (IL)-1beta, were measured using standard assay procedures. The study demonstrates that both desipramine and fluoxetine significantly attenuated the extent and the severity of the macroscopic signs of cell damage. Both drugs significantly reduced tissue MPO activity in a dose-dependent manner. Both desipramine and fluoxetine, at either dose, significantly increased GSH in colonic tissue. Desipramine and fluoxetine, at either dose, significantly reduced TNF-alpha and IL-beta. Desipramine at the dose of 20 mg/kg produced more decrease in the level of TNF-alpha compared with the effect of the smaller dose, but fluoxetine at 10 mg/kg diminished more in the level of IL-1beta compared with the effect of the larger dose. The present data indicate that both desipramine and fluoxetine have anti-inflammatory and antioxidants effects in experimentally induced colitis in rats, opening the avenue to their possible protective role in patients with inflammatory bowel disease. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Desipramine; Dose-Response Relationship, Drug; Fluoxetine; Glutathione; Interleukin-1beta; Male; Peroxidase; Rats; Tumor Necrosis Factor-alpha | 2008 |
Targeted deletion of neuropeptide Y (NPY) modulates experimental colitis.
Neurogenic inflammation plays a major role in the pathogenesis of inflammatory bowel disease (IBD). We examined the role of neuropeptide Y (NPY) and neuronal nitric oxide synthase (nNOS) in modulating colitis.. Colitis was induced by administration of dextran sodium sulphate (3% DSS) or streptomycin pre-treated Salmonella typhimurium (S.T.) in wild type (WT) and NPY (NPY(-/-)) knockout mice. Colitis was assessed by clinical score, histological score and myeloperoxidase activity. NPY and nNOS expression was assessed by immunostaining. Oxidative stress was assessed by measuring catalase activity, glutathione and nitrite levels. Colonic motility was assessed by isometric muscle recording in WT and DSS-treated mice.. DSS/S.T. induced an increase in enteric neuronal NPY and nNOS expression in WT mice. WT mice were more susceptible to inflammation compared to NPY(-/-) as indicated by higher clinical & histological scores, and myeloperoxidase (MPO) activity (p<0.01). DSS-WT mice had increased nitrite, decreased glutathione (GSH) levels and increased catalase activity indicating more oxidative stress. The lower histological scores, MPO and chemokine KC in S.T.-treated nNOS(-/-) and NPY(-/-)/nNOS(-/-) mice supported the finding that loss of NPY-induced nNOS attenuated inflammation. The inflammation resulted in chronic impairment of colonic motility in DSS-WT mice. NPY -treated rat enteric neurons in vitro exhibited increased nitrite and TNF-alpha production.. NPY mediated increase in nNOS is a determinant of oxidative stress and subsequent inflammation. Our study highlights the role of neuronal NPY and nNOS as mediators of inflammatory processes in IBD. Topics: Animals; Catalase; Colitis; Dextran Sulfate; Disease Models, Animal; Gene Deletion; Glutathione; Inflammation; Inflammatory Bowel Diseases; Mice; Mice, Knockout; Neuropeptide Y; Nitric Oxide Synthase Type I; Nitrites; Oxidative Stress; Peroxidase | 2008 |
Adverse effects of chronic circadian desynchronization in animals in a "challenging" environment.
Continuous disruption of circadian rhythms, as seen in human shift workers, has been associated with the development of a number of adverse mental and physiological conditions. However, scientific evidence linking circadian disruption to overall health, particularly in animal models, is not well documented. In this study, we have demonstrated that exposing C57BL/6J mice to 12-h phase shifts every 5 days for 3 mo had no effect on body weight or intestinal physiology. However, when animals were further challenged with dextran sodium sulfate to induce colitis, chronic shifting of the light-dark cycle led to a dramatic increase in the progression of the colitis as indicated by reduced body weight, abnormal intestinal histopathology, and an exacerbated inflammatory response. These data indicate that circadian disruption is an important predisposing factor that may provoke the onset or worsening of various disease states such as inflammatory disorders. This study provides further evidence for continued investigations using animal models of circadian disruption to examine the consequences of circadian disruption on health when organisms are faced with a "challenging" environment. Topics: Adaptation, Physiological; Animals; Body Weight; Chronic Disease; Chronobiology Disorders; Circadian Rhythm; Colitis; Colon; Dextran Sulfate; Environment; Male; Mice; Mice, Inbred C57BL; Peroxidase; Photoperiod; Risk Factors | 2008 |
Pathophysiologic effects of phenylbutazone on the right dorsal colon in horses.
To determine pathophysiologic effects of phenylbutazone on the equine right dorsal colon (RDC).. 12 healthy adult horses.. A controlled crossover observational study was conducted. Clinical and serum variables, colonic inflammation (histologic grading), and measurement of myeloperoxidase (MPO) activity, malondialdehyde (MDA) and prostaglandin E(2) (PGE(2)) concentrations, ingesta volatile fatty acid (VFA) content, and arterial blood flow in the RDC were evaluated for a 21-day period in horses administered phenylbutazone (8.8 mg/kg, PO, q 24 h) or a control substance.. Data from 8 horses were analyzed. Plasma albumin concentrations decreased significantly from days 10 to 21 during phenylbutazone treatment, compared with results during the same days for the control treatment. Phenylbutazone treatment caused neutropenia (< 3.0 x 10(3) cells/microL). No other clinical or hematologic abnormalities were detected for phenylbutazone or control treatments. Two horses developed colitis while receiving phenylbutazone. No significant differences were detected in the RDC between phenylbutazone and control treatments for MPO activity, MDA and PGE(2) concentrations, and histologic evidence of inflammation. Arterial blood flow in the RDC was significantly increased during phenylbutazone treatment, compared with values for the control treatment. Differences were identified in VFA production during phenylbutazone treatment, compared with the control treatment, with a decrease in acetic acid concentrations over time.. Prolonged phenylbutazone administration caused hypoalbuminemia, neutropenia, changes in RDC arterial blood flow, and changes in VFA production. Veterinarians should monitor serum albumin concentrations and neutrophil counts and be cautious when making dosing recommendations for phenylbutazone treatment of horses. Topics: Animals; Colitis; Colon; Cross-Over Studies; Fatty Acids; Horse Diseases; Horses; Malondialdehyde; Peroxidase; Phenylbutazone; Prostaglandins E; Regional Blood Flow; Time Factors | 2008 |
Tanshinone IIA ameliorates trinitrobenzene sulfonic acid (TNBS)-induced murine colitis.
Inflammatory bowel diseases are characterized by proinflammatory cytokines, oxidative stress, and tissue damage. Recently, tanshinone had been shown to act as an antioxidant, and to have anti-inflammatory bioactivity. The study was carried out to investigate the effect of tanshinone IIA on the inflammatory response of experimental colitis. Murine colitis was induced by trinitrobenzene sulfonic acid (TNBS). Ten or 20 mg tanshinone IIA was administrated to mice 4 h before the induction of colitis, and repeated daily until the mice were sacrificed. Colonic inflammation was examined by histological analysis, myeloperoxidase (MPO) activity, and the production of proinflammatory cytokines in colonic tissue. Activation of nuclear factor-kappa B was identified by western blot and immunohistochemistry, and oxidative stress was shown by glutathione (GSH) level in tissue. The mice with colitis treated by tanshinone IIA showed less tissue damage, lower MPO activity, less production of TNF-alpha and IL-1beta, a higher level of GSH in colonic tissue, and downregulated activation of nuclear factor-kappa B in lamina propria mononuclear cells, compared with those of the untreated colitis group. Our data indicates that tanshinone IIA inhibits inflammatory response of colitis by downregulating the production of proinflammatory cytokines, and attenuating oxidative stress, which suggests that tanshinone IIA may be a new potential management for inflammatory bowel diseases. Topics: Abietanes; Actins; Animals; Anti-Inflammatory Agents, Non-Steroidal; Blotting, Western; Colitis; Colon; Dose-Response Relationship, Drug; Glutathione; Immunohistochemistry; Interleukin-1beta; Male; Mice; Mice, Inbred BALB C; NF-kappa B; Peroxidase; Phenanthrenes; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2008 |
Blocking lymphotoxin beta receptor signalling exacerbates acute DSS-induced intestinal inflammation--opposite functions for surface lymphotoxin expressed by T and B lymphocytes.
The lymphotoxin beta receptor (LTbetaR) signalling pathway is involved in the development of secondary lymphoid organs and the maintenance of organized lymphoid tissues. Additionally, previous studies clearly demonstrated the involvement of the LTbetaR interaction with its ligands in promoting intestinal inflammation. In order to dissect the role of LTbetaR activation in the mouse model of acute DSS-induced colitis we treated mice with a functional inhibitor of LTbetaR activation (LTbetaR:Ig) and compared it to disease in LTbetaR-deficient and LTalphabeta-deficient mice. All these modes of LTbetaR signalling ablation resulted in significant aggravation of the disease and in release of inflammatory cytokines such as TNF, IL-6, and IFNgamma. Finally, using mice with conditionally ablated expression of membrane bound LTbeta on T or B cells, respectively, distinct and opposite contributions of surface LTbeta expressed on T or B cells was found. Thus, activation of LTbetaR by LTalphabeta mainly expressed on T lymphocytes is crucial for the down regulation of the inflammatory response in this experimental model. Topics: Acute Disease; Animals; B-Lymphocytes; Colitis; Disease Models, Animal; Female; Immunoglobulins; Inflammation; Ligands; Lymphotoxin beta Receptor; Lymphotoxin-beta; Mice; Mice, Inbred C57BL; Peroxidase; Signal Transduction; T-Lymphocytes; Weight Loss | 2008 |
Immune modulatory treatment of trinitrobenzene sulfonic acid colitis with calcitriol is associated with a change of a T helper (Th) 1/Th17 to a Th2 and regulatory T cell profile.
A number of recent studies testify that calcitriol alone or in combination with corticosteroids exerts strong immune modulatory activity. As a new approach, we evaluated the protolerogenic potential of calcitriol and dexamethasone in acute T helper (Th)1-mediated colitis in mice. A rectal enema of trinitrobenzene sulfonic acid (TNBS) (100 mg/kg) was applied to BALB/c mice. Calcitriol and/or dexamethasone were administered i.p. from days 0 to 3 or 3 to 5 following the instillation of the haptenating agent. Assessment of colitis severity was performed daily. Colon tissue was analyzed macroscopically and microscopically, and myeloperoxidase activity, as well as cytokine levels [tumor necrosis factor-alpha, interferon-gamma, interleukin (IL)-12p70, IL-1beta, IL-10, IL-4] were determined by enzyme-linked immunosorbent assay, T-bet, GATA family of transcription factors 3, a Th2 master regulator (GATA3), Foxp3, cytotoxic T-lymphocyte-associated antigen 4 (CTLA4), IL-23p19 and IL-17 expression by immunoblot analysis. The combination of the steroids most effectively reduced the clinical and histopathologic severity of TNBS colitis. Th1-related parameters were down-regulated, whereas Th2 markers like IL-4 and GATA3 were up-regulated. Apart from known steroid effects, calcitriol in particular promoted regulatory T cell profiles as indicated by a marked increase of IL-10, TGFbeta, FoxP3, and CTLA4. Furthermore, analysis of dendritic cell mediators responsible for a proinflammatory differentiation of T cells revealed a significant reduction of IL-12p70 and IL23p19 as well as IL-6 and IL-17. Thus, our data support a rationale for a steroid-sparing, clinical application of calcitriol derivatives in inflammatory bowel disease. Furthermore they suggest that early markers of inflammatory dendritic cell and Th17 differentiation qualify as new target molecules for both calcitriol and highly selective immune-modulating vitamin D analogs. Topics: Animals; Anti-Inflammatory Agents; Calcitriol; Calcium; Cell Differentiation; Colitis; Colon; Creatinine; Cytokines; Dexamethasone; Disease Models, Animal; Glucocorticoids; Immunologic Factors; Male; Mice; Mice, Inbred BALB C; Peroxidase; T-Lymphocytes; T-Lymphocytes, Regulatory; Th1 Cells; Th2 Cells; Trinitrobenzenesulfonic Acid | 2008 |
Hyperbaric oxygen therapy is as effective as dexamethasone in the treatment of TNBS-E-induced experimental colitis.
Hyperbaric oxygen (HBO) has been demonstrated to be useful as an adjunctive therapy for Crohn's disease. In the present study, HBO was tested as a treatment for trinitrobenzenesulfonic acid-ethanol (TNBS-E)-induced distal colitis, and its effects were compared with dexamethasone therapy.. A total of 48 Sprague-Dawley rats were separated into six groups: the control, and those treated with vehicle, TNBS-E, HBO, dexamethasone, or combined HBO + dexamethasone. The HBO treatment group was exposed to 100% HBO at 2 ATM for 75 min twice daily at 6-h intervals in a HBO chamber, both on the day of colitis induction and 3 days thereafter. Treatment with intraperitoneal dexamethasone twice daily was started 1 h before the induction of colitis and was continued for 7 days in the dexamethasone group. The rats were decapitated 8 days after the induction of colitis, and the colonic tissue wet weight, macroscopic and microscopic lesion score, and tissue myeloperoxidase (MPO) activity were determined.. HBO therapy decreased the activity of experimental colitis measured by the tissue wet weight, macroscopic score, microscopic score, and MPO activity. The dexamethasone treatment significantly reduced the colitis activity as determined by the tissue MPO activity and wet weight. There were also decreases in the macroscopic and microscopic activity scores with the dexamethasone therapy; however, these changes were not statistically significant. The combined therapy with HBO and dexamethasone provided no additional benefit over HBO therapy alone.. HBO therapy can be a valuable therapeutic option in treatment of patients with inflammatory bowel disease. HBO therapy in the refractory patients deserves further, larger clinical studies. Topics: Animals; Anti-Inflammatory Agents; Colitis; Dexamethasone; Female; Hyperbaric Oxygenation; Male; Peroxidase; Rats; Trinitrobenzenesulfonic Acid | 2008 |
Inhibitory effects of fermented brown rice on induction of acute colitis by dextran sulfate sodium in rats.
Although the pathogenic mechanisms of inflammatory bowel diseases are not fully understood, colonic microbiota may affect the induction of colonic inflammation, and some probiotics and prebiotics have been reported to suppress colitis. The inhibitory effects of brown rice fermented by Aspergillus oryzae (FBRA), a fiber-rich food, on the induction of acute colitis by dextran sulfate sodium (DSS) were examined. Feeding a 5% and 10% FBRA-containing diet significantly decreased the ulcer and erosion area in the rat colon stained with Alcian blue. In another experiment, 10% FBRA feeding decreased the ulcer index (percentage of the total length of ulcers in the full length of the colon) and colitis score, which were determined by macroscopic observation. It also decreased myeloperoxidase activity in the colonic mucosa. Viable cell numbers of Lactobacillus in the feces decreased after DSS administration and was reversely correlated with severity of colitis, while the cell number of Enterobacteriaceae increased after DSS treatment and was positively correlated with colitis severity. These results indicate that FBRA has a suppressive effect on the induction of colitis by DSS and suggest FBRA-mediated modification of colonic microbiota. Topics: Acute Disease; Animals; Aspergillus oryzae; Chi-Square Distribution; Colitis; Colon; Dextran Sulfate; Fermentation; Nutritional Physiological Phenomena; Oryza; Peroxidase; Rats; Rats, Wistar; Statistics, Nonparametric | 2008 |
The effects of caffeic acid phenethyl ester (CAPE) on TNBS-induced colitis in ovariectomized rats.
The aim of this investigation was to examine the effects of caffeic acid phenethyl ester (CAPE) on the development of colitis and antioxidant parameters in bilateral ovariectomized rats subjected to trinitrobenzene sulfonic acid (TNBS)-induced colitis.. Twenty-one Wistar Albino ovariectomized female rats were divided into four subgroups (n = 5 or 6) (colitis control, vehicle control, CAPE 10 and 30 mg/kg, respectively). Colitis was induced using an enema of TNBS and ethanol, following which CAPE was administrated for 3 days to induce colitis and effect of CAPE was subsequently evaluated.. Based on microscopic damage scores, there was no difference between rats of the TNBS-colitis and the vehicle-treated groups, whereas treatment with CAPE 10 and 30 mg/kg, respectively, caused a significant reduction in colon injury compared to that observed in rats of the TNBS-colitis and vehicle-treated groups. The histologies of both treatment groups were not significantly different. In terms of the biochemical analyses, myeloperoxidase levels in rats from the CAPE 10 and 30 mg/kg groups were significantly different from that of the colitis control rats; however, the levels of malondialdehyde (MDA), catalase and reduced glutathione (GSH) were only significantly different from the levels found colitis control rats in rats administered 10 mg/kg. The levels of MDA, GSH and SOD in rats given CAPE were also significantly different from those of rats in the vehicle control group. These results were consistent with histological findings.. CAPE may have a positive effect on the inflammatory bowel disease treatment process and could, therefore, be used as an adjunct therapy in colitis. These effects of CAPE may occur through antiinflammatory and antioxidant mechanisms. Topics: Animals; Caffeic Acids; Catalase; Colitis; Female; Glutathione; Malondialdehyde; Ovary; Peroxidase; Phenylethyl Alcohol; Rats; Rats, Wistar; Statistics, Nonparametric; Trinitrobenzenesulfonic Acid | 2008 |
Protective effects of 2,3,5,4'-tetrahydroxystilbene-2-O-beta-d-glucoside, an active component of Polygonum multiflorum Thunb, on experimental colitis in mice.
Reactive oxygen metabolites (ROMs) and inducible nitric oxide synthase (iNOS) are involved in pathogenesis of inflammatory bowel disease. In this study, we examined the effects of 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside (THSG), an active component extracted from Polygonum multiflorum Thunb, on acetic acid-induced acute colitis and mitomycin C-induced chronic colitis. The inflammatory degree was assessed by histology and myeloperoxidase (MPO) activity. Nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) levels were determined with biochemical methods. In addition, inducible nitric oxide synthase (iNOS) expression was immunohistochemically studied. In acetic acid-induced acute model, THSG (60 and 120 mg/kg) significantly ameliorated colon damage, inhibited the increase of acetic acid-induced MPO activity, depressed MDA and NO level, and enhanced SOD activity. Moreover, the effects of 120 mg/kg THSG were better than that of positive control drug, 5-aminosalicylic acid (5-ASA). In mitomycin C-induced model, THSG (60 mg/kg) administered for 7 days and 24 days, significantly improved colon damage and inhibited MPO activity and MDA content while increased SOD activity only on the 7th day and debased NO level on the 24th day. Furthermore, on the 24th day, the effects of THSG were prior to that of 5-ASA. Additionally, THSG (60 mg/kg) could inhibit iNOS expression in both models. In conclusion, THSG exerts protective effects on experimental colitis through alleviating oxygen and nitrogen free radicals level and down-regulating iNOS expression. Topics: Acetic Acid; Acute Disease; Animals; Anti-Inflammatory Agents; Antioxidants; Chronic Disease; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Gastrointestinal Agents; Glucosides; Malondialdehyde; Mesalamine; Mice; Mitomycin; Nitric Oxide; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Peroxidase; Polygonum; Stilbenes; Superoxide Dismutase; Time Factors | 2008 |
Glabridin, a functional compound of liquorice, attenuates colonic inflammation in mice with dextran sulphate sodium-induced colitis.
Inflammatory bowel disease (IBD) is characterized by detrimental immune reactivity in the gut, and the imbalance between proinflammatory and anti-inflammatory reactivity. The aims of this study were to determine whether oral administration of glabridin, a functional component of liquorice, could ameliorate dextran sulphate sodium (DSS)-induced colitis, as well as to understand the possible underlying mechanisms. Acute experimental colitis was induced in BALB/c mice by treatment with 5% DSS for 7 days. Glabridin (10 or 50 mg/kg/day) was given for 7 days. Treatment with glabridin significantly attenuated mortality, loss of body weight, shortening of the colon and severe clinical symptoms. This was associated with a remarkable amelioration of the disruption of the colonic architecture, a significant reduction in colonic myeloperoxidase (MPO) activity and the production of inflammatory mediators such as nitric oxide (NO), prostaglandin (PG) E2, and proinflammatory cytokines. These results suggest that glabridin-mediated anti-inflammatory action on colorectal sites may be a useful therapeutic approach to IBD. Topics: Animals; Biomarkers; Colitis; Colon; Cytokines; Dextran Sulfate; Dinoprostone; Female; Glycyrrhiza; Immunohistochemistry; Intestinal Mucosa; Isoflavones; Mice; Mice, Inbred BALB C; Models, Animal; Neutrophil Activation; Nitric Oxide; Peroxidase; Phenols; Phytotherapy; Plant Extracts; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger | 2008 |
Lactobacillus casei prevents the development of dextran sulphate sodium-induced colitis in Toll-like receptor 4 mutant mice.
Probiotics, defined as live or attenuated bacteria or bacterial products, confer a significant health benefit to the host. Recently, they have been shown to be useful in the treatment of chronic inflammatory bowel disease and infectious colitis. In this study, we investigated the effect of probiotics on the development of experimental colitis using Toll-like receptor 4 (TLR-4) mutant (lps-/lps-) mice. TLR-4(lps-/lps-) and wild-type (WT) mice were given 2.5% dextran sulphate sodium (DSS) in drinking water to induce colitis with or without Lactobacillus casei pretreatment. Clinical and histological activity of DSS-colitis was attenuated markedly both in TLR-4(lps-/lps-) and WT mice pretreated with L. casei. Interestingly, histological activity was less severe in TLR-4(lps-/lps-) mice than in WT mice. The levels of myeloperoxidase activity and interleukin (IL)-12p40 were attenuated in pretreated TLR-4(lps-/lps-) mice after DSS administration. By contrast, transforming growth factor (TGF)-beta and IL-10 mRNA and protein expressions were increased markedly in pretreated TLR-4(lps-/lps-) mice. The current results suggest that L. casei has a preventive effect in the development of acute DSS-induced colitis and its action depends largely upon TLR-4 status. L. casei modulates the expression of inflammatory cytokines and down-regulates neutrophilic infiltration in the case of incomplete TLR-4 complex signalling. Topics: Animals; Biomarkers; Colitis; Colon; Dextran Sulfate; Enzyme-Linked Immunosorbent Assay; Interleukin-10; Interleukin-12 Subunit p40; Intestinal Mucosa; Lacticaseibacillus casei; Mice; Mice, Inbred BALB C; Mice, Knockout; Models, Animal; Peroxidase; Probiotics; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Toll-Like Receptor 4; Transforming Growth Factor beta | 2008 |
Therapeutic effect of epigallocatechin-3-gallate in a mouse model of colitis.
Epigallocatechin-3-gallate (EGCG), a green tea catechin, has been shown to inhibit signaling pathways involved in inflammation, including nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1), which are important inducers of pro-inflammatory mediators. Aim of our study was to evaluate the therapeutic efficacy of EGCG in experimental colitis, which was induced by rectal administration of trinitrobenzenesulfonic acid (TNBS) in C57/BL6 mice. Mice were treated twice daily with vehicle or with EGCG (10 mg/kg) intraperitoneally, and sacrificed on days 1, 3, and 7 after TNBS administration. After induction of colitis, vehicle-treated mice experienced bloody diarrhea and loss of body weight. A remarkable colonic damage with hemorrhage, ulcers, and edema was observed and was associated with neutrophil infiltration as evaluated by myeloperoxidase (MPO) activity. Elevated plasma levels of tumor necrosis factor alpha, interleukin (IL)-6, IL-10 and keratinocyte-derived chemokine were also found. These events were paralleled by increased DNA binding of NF-kappaB and AP-1 in the colon of the vehicle-treated group. In contrast, the EGCG-treated mice experienced a very mild diarrhea and no weight loss. Damage of the colon was characterized by edema and hyperemia only. Tissue levels of MPO were also significantly reduced when compared to vehicle-treated mice. These beneficial effects of EGCG were associated with a significant reduction of NF-kappaB and AP-1 activation. However, treatment with EGCG did not reduce plasma cytokine levels. Our data demonstrate that EGCG may be beneficial in colitis through selective immunomodulatory effects, which may be mediated, at least in part, by inhibition of NF-kappaB and AP-1. Topics: Animals; Antioxidants; Catechin; Colitis; Cytokines; Disease Models, Animal; Injections, Intraperitoneal; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; NF-kappa B; Peroxidase; Tea; Transcription Factor AP-1; Trinitrobenzenesulfonic Acid | 2008 |
Saccharomyces boulardii ameliorates Citrobacter rodentium-induced colitis through actions on bacterial virulence factors.
Saccharomyces boulardii has received increasing attention as a probiotic effective in the prevention and treatment of infectious and inflammatory bowel diseases. The aim of this study was to examine the ameliorating effects of S. boulardii on Citrobacter rodentium colitis in vivo and identify potential mechanisms of action. C57BL/6 mice received 2.5 x 10(8) C. rodentium by gavage on day 0, followed by S. boulardii (25 mg; 5 x 10(8) live cells) gavaged twice daily from day 2 to day 9. Animal weights were monitored until death on day 10. Colons were removed and assessed for epithelial barrier function, histology, and myeloperoxidase activity. Bacterial epithelial attachment and type III secreted proteins translocated intimin receptor Tir (the receptor for bacterial intimin) and EspB (a translocation apparatus protein) required for bacterial virulence were assayed. In infected mice, S. boulardii treatment significantly attenuated weight loss, ameliorated crypt hyperplasia (234.7 +/- 7.2 vs. 297.8 +/- 17.6 microm) and histological damage score (0.67 +/- 0.67 vs. 4.75 +/- 0.75), reduced myeloperoxidase activity (2.1 +/- 0.4 vs. 4.7 +/- 0.9 U/mg), and attenuated increased mannitol flux (17.2 +/- 5.0 vs. 31.2 +/- 8.2 nm.cm(-2).h(-1)). The ameliorating effects of S. boulardii were associated with significantly reduced numbers of mucosal adherent C. rodentium, a marked reduction in Tir protein secretion and translocation into mouse colonocytes, and a striking reduction in EspB expression and secretion. We conclude that S. boulardii maintained colonic epithelial barrier integrity and ameliorated inflammatory sequelae associated with C. rodentium infection by attenuating C. rodentium adherence to host epithelial cells through putative actions on the type III secretion system. Topics: Adhesins, Bacterial; Animals; Bacterial Adhesion; Bacterial Outer Membrane Proteins; Bacterial Proteins; Bacterial Translocation; Citrobacter rodentium; Colitis; Colon; Enterobacteriaceae Infections; Intestinal Mucosa; Mannitol; Membrane Potentials; Mice; Mice, Inbred C57BL; Permeability; Peroxidase; Probiotics; Receptors, Cell Surface; Saccharomyces; Time Factors; Transcription, Genetic; Virulence; Virulence Factors | 2008 |
Down-regulation of hepatic cytochrome P450 enzymes in rats with trinitrobenzene sulfonic acid-induced colitis.
Hepatic cytochrome P450 (P450) enzymes are down-regulated during inflammation. In this study, an animal model of inflammatory bowel disease was subjected to characterization of hepatic P450 expression under inflammatory conditions. Rats were treated intracolonically with 100 mg/kg trinitrobenzene sulfonic acid (TNBS) dissolved in 30% ethanol, and homogenates of colonic mucosa and hepatic microsomes of the rats were prepared. The colitis was accompanied by appearance of higher levels of portal endotoxin, interleukin-6, and nitric oxide metabolites and decreases in contents and activities for hepatic CYP3A2, CYP2C11, and, to a lesser extent, CYP1A2 and CYP2E1. Nimesulide, a preferential COX-2 inhibitor, protected rats with TNBS-induced colitis (TNBS-colitis) against the down-regulation of hepatic CYP3A2. Polymyxin B, which neutralizes endotoxin, curcumin, which has anti-inflammatory properties, and gadolinium chloride, which inactivates macrophages, attenuated the down-regulation of CYP3A2. Similar effects were observed in other P450s such as CYP2C11, but the agents were less effective in attenuating the down-regulation. Our data suggest that endogenous substances leaked from damaged colon in the rats with TNBS-colitis activate Kupffer cells, leading to down-regulation of hepatic P450s with differential susceptibility to the inflammatory stimuli. The colitis model, instead of exogenous administration of lipopolysaccharide or cytokines, could be applied to the study on mechanisms for altered hepatic P450 expression and other liver functions under mild inflammatory conditions. Topics: Animals; Colitis; Cytochrome P-450 Enzyme System; Down-Regulation; Intestinal Mucosa; Isoenzymes; Liver; Liver Diseases; Male; Peroxidase; Rats; Trinitrobenzenesulfonic Acid | 2008 |
Glucocorticoid availability in colonic inflammation of rat.
Recent in vitro studies have shown the involvement of pro-inflammatory cytokines in the regulation of the local metabolism of glucocorticoids via 11beta-hydroxysteroid dehydrogenase type 1 and type 2 (11HSD1 and 11HSD2). However, direct in vivo evidence for a relationship among the local metabolism of glucocorticoids, inflammation and steroid enzymes is still lacking. We have therefore examined the changes in the local metabolism of glucocorticoids during colonic inflammation induced by TNBS and the consequences of corticosterone metabolism inhibition by carbenoxolone on 11HSD1, 11HSD2, cyclooxygenase 2 (COX-2), mucin 2 (MUC-2), tumor necrosis factor alpha (TNF-alpha), and interleukin 1beta (IL-1beta). The metabolism of glucocorticoids was measured in tissue slices in vitro and their 11HSD1, 11HSD2, COX-2, MUC-2, TNF-alpha, and IL-1beta mRNA abundances by quantitative reverse transcription-polymerase chain reaction. Colitis produced an up-regulation of colonic 11HSD1 and down-regulation of 11HSD2 in a dose-dependent manner, and these changes resulted in a decreased capacity of the inflamed tissue to inactivate tissue corticosterone. Similarly, 11HSD1 transcript was increased in colonic intraepithelial lymphocytes of TNBS-treated rats. Topical intracolonic application of carbenoxolone stimulated 11HSD1 mRNA and partially inhibited 11HSD2 mRNA and tissue corticosterone inactivation and these changes were blocked by RU-486. The administration of budesonide mimicked the effect of carbenoxolone. In contrast to the local metabolism of glucocorticoids, carbenoxolone neither potentiates nor diminishes gene expression for COX-2, TNF-alpha, and IL-1beta, despite the fact that budesonide down-regulated all of them. These data indicate that inflammation is associated with the down-regulation of tissue glucocorticoid catabolism. However, these changes in the local metabolism of glucocorticoids do not modulate the expression of COX-2, TNF-alpha, and IL-1beta in inflamed tissue. Topics: 11-beta-Hydroxysteroid Dehydrogenase Type 1; 11-beta-Hydroxysteroid Dehydrogenase Type 2; Animals; Budesonide; Carbenoxolone; Colitis; Colon; Corticosterone; Cyclooxygenase 2; Disease Models, Animal; Glucocorticoids; Hormone Antagonists; Interleukin-1beta; Male; Mifepristone; Mucin-2; Mucins; Peroxidase; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2008 |
Attenuation of inflammation and cytokine production in rat colitis by a novel selective inhibitor of leukotriene A4 hydrolase.
Leukotriene B(4) (LTB(4)), formed by the sequential actions of the 5-lipoxygenase (5-LO) and leukotriene A(4) hydrolase (LTA(4)H), is a pro-inflammatory mediator implicated in the pathogenesis of inflammatory bowel disease. However, inhibitors of 5-LO have not proved to be consistent in their therapeutic efficacy in colitis. Another approach to inhibiting LTB(4) synthesis is through the use of inhibitors of LTA(4)H, such as the novel, potent and selective compound, JNJ 26993135.. The effect of oral administration of JNJ 26993135 has been evaluated in a rat model of colitis provoked by colonic instillation of trinitrobenzenesulphonic acid (TNBS). The extent and severity of the macroscopic inflammatory response, the colonic levels of myeloperoxidase (MPO) and LTB(4) and of the pro-inflammatory cytokines, tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were measured.. Oral administration of JNJ 26993135 (5, 15 and 30 mg kg(-1), twice a day) dose-dependently reduced both the extent and intensity of the colonic inflammatory damage observed 3 days after TNBS challenge. JNJ 26993135 also dose-dependently reduced the elevated colonic levels of LTB(4), as well as the inflammatory biomarkers, MPO, IL-6 and TNF-alpha. This dosing regimen was supported by the pharmacokinetic profile of JNJ 26993135, along with the demonstration of the inhibition of ex vivo production of LTB(4) in whole blood following oral administration.. These results with JNJ 26993135 in the rat TNBS model support the role of LTB(4) in colitis and the potential value of targeting LTA(4)H for the treatment of inflammatory bowel diseases. Topics: Administration, Oral; Animals; Benzothiazoles; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Delivery Systems; Enzyme Inhibitors; Epoxide Hydrolases; Inflammation; Interleukin-6; Male; Peroxidase; Piperidines; Rats; Rats, Wistar; Severity of Illness Index; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2008 |
Role of M-CSF-dependent macrophages in colitis is driven by the nature of the inflammatory stimulus.
Although macrophages are considered a critical factor in determining the severity of acute inflammatory responses in the gut, recent evidence has indicated that macrophages may also play a counterinflammatory role. In this study, we examined the role of a macrophage subset in two models of colitis. Macrophage colony-stimulating factor (M-CSF)-deficient osteopetrotic mice (op/op) and M-CSF-expressing heterozygote (+/?) mice were studied following the induction of colitis by either dinitrobenzene sulfonic acid (DNBS) or dextran sulfate sodium (DSS). DNBS induced a severe colitis in M-CSF-deficient op/op mice compared with +/? mice. This was associated with increased mortality and more severe macroscopic and microscopic injury. Colonic tissue myeloperoxidase (MPO) activity as well as concentrations of TNF-alpha, IL-1beta, and IL-6 were higher and IL-10 lower in op/op mice with DNBS colitis. The severity of inflammation and mortality was attenuated in op/op mice that had received human recombinant M-CSF prior to the induction of colitis. In contrast, op/op mice appeared less vulnerable to colitis induced by DSS. Macroscopic damage, microscopic injury, MPO activity, and tissue concentrations of TNF-alpha, IL-1beta, and IL-6 were all lower in op/op mice compared with +/? mice with DSS colitis, and no changes were seen in IL-10. Macrophage inflammatory protein-1alpha concentrations were increased in op/op but not +/? mice following colitis induced by DNBS but not DSS. These results indicate that M-CSF-dependent macrophages may play either a pro- or counterinflammatory role in acute experimental colitis, depending on the stimulus used to induce colitis. Topics: Animals; Benzenesulfonates; Colitis; Cytokines; Data Interpretation, Statistical; Dextran Sulfate; Dinitrofluorobenzene; Immunohistochemistry; Inflammation; Macrophage Colony-Stimulating Factor; Macrophages; Mice; Mice, Knockout; Peroxidase; Receptors, CCR1 | 2008 |
An arachidonic acid-enriched diet does not result in more colonic inflammation as compared with fish oil- or oleic acid-enriched diets in mice with experimental colitis.
Fish oils (FO) - rich in EPA and DHA - may protect against colitis development. Moreover, inflammatory bowel disease patients have elevated colonic arachidonic acid (AA) proportions. So far, effects of dietary AA v. FO on colitis have never been examined. We therefore designed three isoenergetic diets, which were fed to mice for 6 weeks preceding and during 7 d dextran sodium sulfate colitis induction. The control diet was rich in oleic acid (OA). For the other two diets, 1.0 % (w/w) OA was exchanged for EPA+DHA (FO group) or AA. At 7 d after colitis induction, the AA group had gained weight (0.46 (sem 0.54) g), whereas the FO and OA groups had lost weight (- 0.98 (SEM 0.81) g and - 0.79 (SEM 1.05) g, respectively; P < 0.01 v. AA). The AA group had less diarrhoea than the FO and OA groups (P < 0.05). Weight and length of the colon, histological scores and cytokine concentrations in colon homogenates showed no differences. Myeloperoxidase concentrations in plasma and polymorphonuclear cell infiltration in colon were decreased in the FO group as compared with the OA group. We conclude that in this mice model an AA-enriched diet increased colonic AA content, but did not result in more colonic inflammation as compared with FO- and OA-enriched diets. As we only examined effects after 7 d and because the time point for evaluating effects seems to be important, the present results should be regarded as preliminary. Future studies should further elucidate differential effects of fatty acids on colitis development in time. Topics: Animals; Arachidonic Acid; Body Weight; Colitis; Colon; Cytokines; Dextran Sulfate; Diet; Disease Models, Animal; Fatty Acids; Female; Fish Oils; Food Analysis; Mice; Mice, Inbred C57BL; Oleic Acid; Organ Size; Peroxidase; Serum Amyloid P-Component | 2008 |
The involvement of heme oxygenase-1 activity in the therapeutic actions of 5-aminosalicylic acid in rat colitis.
The mechanism of action of 5-aminosalicylic acid (5-ASA), the active therapeutic moiety of a number of clinically used anti-colitic agents, is unclear. The present study investigates whether the beneficial effects in vivo could involve induction of the heat shock protein, heme oxygenase-1 (HO-1), known to provide endogenous anti-oxidant and anti-inflammatory moieties which can modulate colonic inflammation. The effects of 5-ASA on the colonic expression and activity of HO-1 along with its effect on the inflammatory damage have been evaluated in the colitis provoked by instillation of trinitrobenzene sulphonic acid (TNBS) over 48 h in the rat. Intracolonic administration of 5-ASA (8, 25 and 75 mg/kg/day) dose-dependently reduced the TNBS-provoked macroscopic colonic inflammatory injury, myeloperoxidase (MPO) activity and TNF-alpha levels, while also dose-dependently increasing colonic heme oxygenase enzyme activity. Colonic HO-1 protein expression, determined by Western blot analysis in this colitis model, was likewise further induced by 5-ASA. Intracolonic administration of 5-ASA alone under unchallenged conditions also induced colonic HO-1 protein expression and stimulated heme oxygenase enzyme activity. Administration of zinc protoporphyrin (50 micromol/kg/day, s.c.), which prevented the increase in colonic heme oxygenase activity, abolished the anti-colitic effect of 5-ASA. These results suggest that 5-ASA may exert its colonic anti-oxidant and anti-inflammatory effects in vivo in part through the up-regulation of HO-1 enzyme expression and activity. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Blotting, Western; Colitis; Disease Models, Animal; Heme Oxygenase-1; Male; Mesalamine; Peroxidase; Protoporphyrins; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Up-Regulation | 2008 |
The effects of intra-rectal and intra-peritoneal application of Origanum onites L. essential oil on 2,4,6-trinitrobenzenesulfonic acid-induced colitis in the rat.
The aim of the present study is to investigate the treatment efficiency of intra-rectal (IR) and intra-peritoneal (IP) application of Origanum onites essential oil (OOEO), which is a well-known antioxidant, in the colitis model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) and ethanol (E) in comparison with dexamethasone therapy through the morphologic damage score. Monoclonal antibodies against intercellular adhesion molecule-1 (ICAM-1, CD54), anti-rat granulocytes, and myeloperoxidase (MPO), were also investigated immunohistochemically. There was a significant difference in terms of ulceration, mucus cell depletion, inflammatory cell infiltration, vascular dilatation (p<0.001), crypt abscesses (p<0.01), and edema (p<0.05) between OOEO-1mg/kg-IR and control colitis groups. A significant difference was encountered in terms of mucus cell depletion, crypt abscesses, inflammatory cell infiltration, vascular dilatation (p<0.01), and ulceration (p<0.05) between the OOEO-0.1mg/kg-IR and control colitis groups. A significant difference was noticed in terms of ulceration, inflammatory cell infiltration, mucus cell depletion (p<0.001), vascular dilatation (p<0.01), and mucosal atrophy (p<0.05) between the OOEO-1mg/kg-IP and control colitis groups. There was a significant difference in terms of ulceration, mucus cell depletion, inflammatory cell infiltration (p<0.001), crypt abscesses, vascular dilatation (p<0.01), and mucosal atrophy (p<0.05) between the OOEO-0.1mg/kg-IP and control colitis groups. No significant difference was determined in terms of ulceration, inflammatory cyst, mucosal atrophy, edema, and vascular dilatation between the dexamethazone and control colitis groups (p>0.05). Under the present conditions, we concluded that IR and IP OOEO treatment, applied at the dosage of 0.1 or 1mg/kg/day, have a significant protective effect on the colonic injury. Topics: Administration, Rectal; Animals; Antioxidants; Colitis; Colitis, Ulcerative; Colon; Dexamethasone; Disease Models, Animal; Ethanol; Gas Chromatography-Mass Spectrometry; Immunohistochemistry; Injections, Intraperitoneal; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Oils, Volatile; Origanum; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2008 |
Melatonin reduces bacterial translocation and apoptosis in trinitrobenzene sulphonic acid-induced colitis of rats.
To investigate the effects of exogenous melatonin on bacterial translocation and apoptosis in a rat ulcerative colitis model.. Rats were randomly assigned to three groups: group I: control, group II: experimental colitis, group III: colitis plus melatonin treatment. On d 11 after colitis, plasma tumor necrosis factor-alpha, portal blood endotoxin levels, colon tissue myeloperoxidase and caspase-3 activity were measured. Bacterial translocation was quantified by blood, lymph node, liver and spleen culture.. We observed a significantly reduced incidence of bacterial translocation to the liver, spleen, mesenteric lymph nodes, portal and systemic blood in animals treated with melatonin. Treatment with melatonin significantly decreased the caspase-3 activity in colonic tissues compared to that in trinitrobenzene sulphonic acid- treated rats (16.11 +/- 2.46 vs 32.97 +/- 3.91, P < 0.01).. Melatonin has a protective effect on bacterial translocation and apoptosis. Topics: Animals; Apoptosis; Bacterial Translocation; Caspase 3; Colitis; Colon; Endotoxins; Humans; Male; Melatonin; Peroxidase; Random Allocation; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2008 |
Probiotics and blueberry attenuate the severity of dextran sulfate sodium (DSS)-induced colitis.
We studied the anti-inflammatory properties of probiotic strains and blueberry in a colitis model. The disease activity index (DAI) was significantly lower on days 9 and 10 in all groups compared to the colitis control. Myeloperoxidase (MPO) and bacterial translocation to the liver and to the mesenteric lymph nodes (MLN) decreased significantly in all groups compared to colitis control. Cecal Enterobacteriaceae count decreased significantly in blueberry with and without probiotics compared to the other groups. Lactobacillus plantarum reisolated from the cecal content in the presence of blueberry, contrary to Lactobacillus fermentum. Colonic MDA decreased significantly in all groups, except the L. fermentum group, compared to the colitis control. The cecal concentration of acetic, propionic, and butyricbutyric acid was significantly higher in the L. plantarum group, while the L. fermentum group yielded the highest concentration of lactic acid compared with all other groups. Lactobacillus plantarum DSM 15313, Lactobacillus fermentum 35D, and blueberry alone and in combination improve the DAI, reduce bacterial translocation, and reduce inflammation. Topics: Animals; Bacterial Translocation; Blueberry Plants; Chemokine CCL2; Chemokine CXCL1; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Enterobacteriaceae; Fatty Acids, Volatile; Lactobacillus plantarum; Lipid Peroxidation; Liver; Lymph Nodes; Peroxidase; Probiotics; Rats; Rats, Sprague-Dawley; Severity of Illness Index | 2008 |
In vitro and in vivo effects of the probiotic Escherichia coli strain M-17: immunomodulation and attenuation of murine colitis.
We examined the in vitro and in vivo effects of a probiotic, Escherichia coli strain M-17 (EC-M17), on NF-kappaB signalling, cytokine secretion and efficacy in dextran sulfate sodium (DSS)-induced murine colitis. NF-kappaB signalling was assessed using an NF-kappaB luciferase reporter cell line that was stimulated with TNF-alpha (100 ng/ml). p65 Nuclear binding and cytokine secretion (TNF-alpha, IL-1beta and IL-6) were evaluated using a RAW 264.7 macrophage cell line that was exposed to lipopolysaccharide (LPS; 5 microg/ml). Mice were administered vehicle, EC-M17, metronidazole, or EC-M17 plus metronidazole for 13 d. During the final 6 d, mice also received 2 % DSS. Parameters evaluated included disease activity index (DAI), histology, myeloperoxidase and NF-kappaB p65. EC-M17 dose dependently inhibited TNF-alpha-induced NF-kappaB signalling. At 5 x 109 colony-forming units/ml, EC-M17 inhibited NF-kappaB by >95 %. LPS-induced nuclear p65 binding was significantly inhibited (78 %; P 90 %) the LPS-induced secretion of TNF-alpha, IL-1beta and IL-6. In mice with DSS-induced colitis, EC-M17, metronidazole, and EC-M17 plus metronidazole significantly reduced DAI and colonic histology scores. Both EC-M17 and metronidazole reduced colonic IL-12, IL-6, IL-1beta and interferon-gamma. The combination of EC-M17 plus metronidazole resulted in more substantial cytokine reductions than were found with either treatment alone, and combination therapy significantly (P < 0.05 in both cases) reduced IL-1beta compared with EC-M17 and colonic histology scores compared with metronidazole. Alone, and in combination with metronidazole, EC-M17 improved murine colitis, probably due to an inhibitory effect on NF-kappaB signalling. Topics: Animals; Anti-Infective Agents; Cell Line; Colitis; Colon; Escherichia coli; Humans; Interleukin-1beta; Interleukin-6; Luciferases; Macrophages; Male; Metronidazole; Mice; Mice, Inbred C57BL; Models, Animal; Peroxidase; Probiotics; Signal Transduction; Transcription Factor RelA; Tumor Necrosis Factor-alpha | 2008 |
Dextran sulfate sodium-induced acute colonic inflammation in angiotensin II type 1a receptor deficient mice.
Angiotensin II (Ang II) receptor blockers have been reported to contribute to cytoprotective effects in various organs. However, the role of renin-angiotensin system (RAS) in modulation of the inflammatory bowel disease (IBD) remains unclear. In this study we assessed the role of angiotensin II type 1a (AT1a) receptor on the outcome of dextran sulfate sodium (DSS)-induced acute colitis by employing AT1a receptor deficient mice.. The acute colitis was induced in wild type (WT) and AT1a receptor deficient mice by giving orally 3% DSS in drinking water for 7 days.. Induction of DSS colitis resulted in up-regulation of Ang II and AT1a receptor in the colonic mucosa of WT mice. In parallel, loss of body weight, an increase in disease activity index (DAI), and the shortening of colon were found in DSS-challenged WT mice. In addition, an increase in thiobarbituric acid (TBA)-reactive substances and myeloperoxidase (MPO) activity, along with the up-regulation of tumor necrosis factor (TNF)-alpha were detected in the colonic mucosa of DSS-challenged WT mice. The endpoints mentioned above were significantly ameliorated in DSS-challenged AT1a receptor deficient mice.. RAS is involved in the pathophysiology of DSS-induced colitis and AT1a receptor may be a novel therapeutic target for the treatment of IBD. Topics: Angiotensin II; Animals; Body Weight; Colitis; Colon; Dextran Sulfate; Inflammation; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Peroxidase; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Tumor Necrosis Factor-alpha | 2008 |
Ameliorative effects of bombesin and neurotensin on trinitrobenzene sulphonic acid-induced colitis, oxidative damage and apoptosis in rats.
To investigate the effects of bombesin (BBS) and neurotensin (NTS) on apoptosis and colitis in an ulcerative colitis model.. In this study, a total of 50 rats were divided equally into 5 groups. In the control group, no colitis induction or drug administration was performed. Colitis was induced in all other groups. Following the induction of colitis, BBS, NTS or both were applied to three groups of rats. The remaining group (colitis group) received no treatment. On the 11th d after induction of colitis and drug treatment, blood samples were collected for TNF-alpha and IL-6 level studies. Malondialdehyde (MDA), carbonyl, myeloperoxidase (MPO) and caspase-3 activities, as well as histopathological findings, evaluated in colonic tissues.. According to the macroscopic and microscopic findings, the study groups treated with BBS, NTS and BBS + NTS showed significantly lower damage and inflammation compared with the colitis group (macroscopic score, 2.1 +/- 0.87, 3.7 +/- 0.94 and 2.1 +/- 0.87 vs 7.3 +/- 0.94; microscopic score, 2.0 +/- 0.66, 3.3 +/- 0.82 and 1.8 +/- 0.63 vs 5.2 +/- 0.78, P < 0.01). TNF-alpha and IL-6 levels were increased significantly in all groups compared with the control group. These increases were significantly smaller in the BBS, NTS and BBS + NTS groups compared with the colitis group (TNF-alpha levels, 169.69 +/- 53.56, 245.86 +/- 64.85 and 175.54 +/- 42.19 vs 556.44 +/- 49.82; IL-6 levels, 443.30 +/- 53.99, 612.80 +/- 70.39 and 396.80 +/- 78.43 vs 1505.90 +/- 222.23, P < 0.05). The colonic MPO and MDA levels were significantly lower in control, BBS, NTS and BBS + NTS groups than in the colitis group (MPO levels, 24.36 +/- 8.10, 40.51 +/- 8.67 and 25.83 +/- 6.43 vs 161.47 +/- 38.24; MDA levels, 4.70 +/- 1.41, 6.55 +/- 1.12 and 4.51 +/- 0.54 vs 15.60 +/- 1.88, P < 0.05). Carbonyl content and caspase-3 levels were higher in the colitis and NTS groups than in control, BBS and BBS + NTS groups (carbonyl levels, 553.99 +/- 59.58 and 336.26 +/- 35.72 vs 209.76 +/- 30.92, 219.76 +/- 25.77 and 220.34 +/- 36.95; caspase-3 levels, 451.70 +/- 68.27 and 216.20 +/- 28.17 vs 28.60 +/- 6.46, 170.50 +/- 32.37 and 166.50 +/- 30.95, P < 0.05).. The results of this study suggest BBS and NTS, through their anti-inflammatory actions, support the maintenance of colonic integrity and merit consideration as potential agents for ameliorating colonic inflammation. Topics: Animals; Apoptosis; Bombesin; Caspase 3; Colitis; Colon; Interleukin-6; Male; Malondialdehyde; Neurotensin; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2008 |
Matrix metalloproteinase-7 (matrilysin) controls neutrophil egress by generating chemokine gradients.
Matrilysin [matrix metalloproteinase 7 (MMP7)] is induced by mucosal injury of many tissues. To assess function of this proteinase, we subjected wild-type and Mmp7(-/-) mice to acute colon injury. When matrilysin expression was increasing, 73% of wild-type mice died, whereas only 32% of Mmp7(-/-) mice succumbed. Although re-epithelialization was delayed in Mmp7(-/-) mice, overall injury did not differ markedly between genotypes. We hypothesized that differences in acute inflammation caused increased mortality in wild-type mice. Indeed, whereas overall neutrophil influx into tissue was similar in wild-type and Mmp7(-/-) mice, their location and extent of migration differed between genotypes. Neutrophils were dispersed throughout the mucosa and within the lumen of wild-type mice, but these leukocytes were largely confined to the submucosa in Mmp7(-/-) mice. The levels of neutrophil chemokines, keratinocyte-derived chemokine and MIP-2, increased in the colon tissue of both genotypes, but these factors were detected only in lumenal lavages of wild-type mice. Our findings indicate that matrilysin mediates beneficial and deleterious effects in response to injury. On one hand, it promotes re-epithelialization, but it also controls the transepithelial influx of neutrophils, which if excessive, can lead to tissue damage. Topics: Animals; Cell Movement; Chemokines; Colitis; Colon; Matrix Metalloproteinase 7; Mice; Mice, Inbred C57BL; Neutrophils; Peroxidase; RNA, Messenger | 2008 |
In vitro inhibition of enterobacteria-reactive CD4+CD25- T cells and suppression of immunoinflammatory colitis in mice by the novel immunomodulatory agent VGX-1027.
VGX-1027 is an isozaxoline compound that has recently been found to primarily target the function of murine macrophages but not of T cells, inhibiting secretion of tumor necrosis factor (TNF)-alpha in response to different Toll-like receptor agonists in vitro and in vivo. The well-defined role of innate immunity in inflammatory bowel diseases prompted us to consider the use of VGX-1027 in these diseases leading us to in vitro and in vivo test the drug in related experimental conditions. These consist, respectively, of the proliferation assay of CD4+CD25- T cells to enterobacteria, and the acute inflammatory colitis induced in mice by intracolonic challenge with dinitrobenzene sulfonic acid. The data from the two sets of experiments revealed that VGX-1027 inhibited both proliferation of enterobacterial antigen-reactive CD4+CD25- T cells in vitro and the development of clinical and histological signs of colitis in vivo. The beneficial effect in this model was associated with reduced colonic production of proinflammatory cytokines such as interleukin (IL)-1beta, TNF-alpha, IL-12p70 and interferon (IFN)-gamma and lower content of nuclear factor (NF)-kappaB (p65). These findings seem to warrant investigations of VGX-1027 for use in human. Topics: Acetates; Animals; Antigen-Presenting Cells; Body Weight; CD4-Positive T-Lymphocytes; Cell Proliferation; Cell Separation; Colitis; Cytokines; Diarrhea; Enterobacteriaceae; Female; Gastrointestinal Hemorrhage; Immunologic Factors; Interleukin-2 Receptor alpha Subunit; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Oxazoles; Peroxidase; Transcription Factor RelA | 2008 |
Experimental colitis is associated with ultrastructural changes in inflamed and uninflamed regions of the gastrointestinal tract.
The objective of this study was to examine the ultrastructural changes in cell organelles such as mitochondria, endoplasmic reticulum (ER) and Golgi apparatus in inflamed colon and uninflamed ileum in colitic rats.. Colitis was induced in rats by intracolonic administration of trinitrobenzenesulfonic acid (TNBS). The animals were sacrificed on day 5 after TNBS administration and colonic and ileal samples were used for estimation of myeloperoxidase (MPO) activity, malondialdehyde (MDA) concentration, histologic examination and transmission electron microscopy.. TNBS caused a significant reduction in body weight and an increase in MPO activity in colonic, but not in the ileal samples in animals with colitis. MDA levels were increased both in inflamed colon and the uninflamed ileal segments in colitis. Electron microscopy revealed swelling of mitochondria with broken cristae and disruption of the inner membrane. Colitis also caused fragmentation of the ER with loss of ribosomes and swelling of the Golgi apparatus with distended vesicles in both smooth muscle and epithelial cells in the ileal and colonic segments. These changes were absent in the control rats without colitis.. These findings demonstrate ultrastructural deformities in both the mucosa and smooth muscle in inflamed and uninflamed regions of the gastrointestinal tract in experimental colitis. The structural changes in mitochondria are responsible for reduced ATP, while abnormalities in the ER and the Golgi apparatus may explain a generalized effect on protein synthesis, trafficking and targeting mechanisms, and may account for physiological changes seen in experimental colitis. Topics: Animals; Colitis; Colon; Disease Models, Animal; Endoplasmic Reticulum; Golgi Apparatus; Ileum; Inflammation; Male; Microscopy, Electron, Transmission; Mitochondria; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2008 |
Colonization of mice by Candida albicans is promoted by chemically induced colitis and augments inflammatory responses through galectin-3.
Little is known about the relationship between colonic inflammation and Candida albicans colonization. Galectin-3 (Gal-3) is an intestinal lectin that binds to specific C. albicans glycans and is involved in inflammation.. Colitis was experimentally induced in wild-type and Gal3(-/-) mice using dextran sulfate sodium (DSS) before oral administration of C. albicans. Yeast recovered from stools was quantified. The presence of yeast and inflammation were evaluated in sections of colon by histologic examination, quantification of myeloperoxidase (MPO) activity, and by gene expression for cytokines and innate immune receptors. Serum from mice was collected for determination of anti-yeast mannan antibodies, including anti-Saccharomyces cerevisiae antibodies (ASCA), which are biomarkers of an inflammatory bowel disease.. Inflammation strongly promoted C. albicans colonization. Conversely, C. albicans augmented inflammation induced by DSS, as assessed by histologic scores, MPO activity, and tumor necrosis factor (TNF)-alpha and Toll-like receptor (TLR)-2 expression. C. albicans colonization generated ASCA. The absence of Gal-3 reduced DSS inflammation and abolished the response of TLR-2 and TNF-alpha to C. albicans colonization.. DSS-induced colitis provides a model for establishing C. albicans colonization in mice. This model reveals that C. albicans augments inflammation and confirms the role of Gal-3 in both inflammation and the control of host responses to C. albicans. Topics: Animals; Antibodies, Fungal; Antigens, Fungal; Candida albicans; Candidiasis; Colitis; Colon; Colony Count, Microbial; Cytokines; Dextran Sulfate; Feces; Female; Galectin 3; Gene Expression Profiling; Inflammation; Mannans; Mice; Peroxidase; Receptors, Immunologic; Saccharomyces cerevisiae; Severity of Illness Index | 2008 |
Protease-activated receptor-2 activation: a major actor in intestinal inflammation.
The role of protease-activated receptor-2 (PAR(2)) during intestinal inflammation is still unclear due to the fact that PAR(2)-activating peptide has both pro- and anti-inflammatory properties. The aim of this study was to investigate the effects of PAR(2) deficiency (using PAR(2)-deficient mice, PAR(2)(-/-)) in models of colitis, in order to elucidate the role of endogenous PAR(2) in the process of inflammation in the gut.. Colonic inflammation in wild-type and PAR(2)(-/-) mice was induced by dextran sodium sulfate, trinitrobenzene sulfonic acid (TNBS), a T helper-1 predominant model, or oxazolone, a T helper-2 predominant model. Leukocyte recruitment, assessed by intravital microscopy, and inflammatory parameters (myeloperoxidase (MPO), macroscopic and microscopic damage) were assessed during the development of colitis. Lastly, the protein levels of cyclooxygenases (COXs) and adhesion molecules (ICAM-1, VCAM-1, alpha-M, alpha-4) were assessed by using western blot analysis.. In all three models of colitis, MPO activity, macroscopic damage score and bowel thickness were significantly lower in PAR(2)(-/-) mice. Changes in vessel leukocyte recruitment parameters (rolling and adhesion) were also significantly reduced in PAR(2)(-/-) mice compared to wild-type mice after the induction of colitis. The protein expression of ICAM-1, VCAM-1 and alpha-4 was significantly attenuated, whereas the expression of COX-1 was significantly increased in PAR(2)(-/-) mice challenged with TNBS-induced colitis.. The role of endogenous PAR(2) in the gut is pro-inflammatory and independent of the T helper-1 or -2 cytokine profile. Endogenous PAR(2) activation controls leukocyte recruitment in the colon and thus appears as a new potential therapeutic target for the treatment of inflammatory bowel disease. Topics: Animals; Cell Adhesion Molecules; Colitis; Dextran Sulfate; Disease Models, Animal; Mice; Mice, Inbred C57BL; Oxazolone; Peroxidase; Prostaglandin-Endoperoxide Synthases; Receptor, PAR-2; Trinitrobenzenesulfonic Acid | 2008 |
In utero and postnatal exposure to a phytoestrogen-enriched diet increases parameters of acute inflammation in a rat model of TNBS-induced colitis.
Inflammatory bowel disease (IBD) is very common in Europe and USA. Its incidence in East Asia has been traditionally low, albeit the risk of IBD increases in Asian immigrants adopting western lifestyles, suggesting a strong role of environmental/dietary factors in IBD. A lifelong exposure to phytoestrogen-rich diets has been associated with a decreased risk of developing breast cancer and might also be protective against IBD. We studied the influence of in utero and postnatal exposure to a phytoestrogen (PE)-rich diet on acute inflammation in an animal model of TNBS-induced colitis. Wistar rats were exposed in utero and postnatally to high (genistein: 240 microg/g feed; daidzein: 232 microg/g feed) or very low levels (genistein and daidzein <10 microg/g feed) of phytoestrogen isoflavones fed to pregnant dams with the diet and throughout nursing. After weaning, the offspring had free access to these diets. At the age of 11 weeks, colitis was induced with an enema of TNBS. After 3 days, animals were sacrificed and tissues were collected for histological evaluation and analysis of molecular markers of inflammation. Animals kept on a PE-rich diet (PRD) had higher colon weights than animals on low PE-levels (PDD), suggesting enhanced acute inflammation by phytoestrogens. This result was supported by histological findings and by analysis of myeloperoxidase activity. Interestingly, relative mRNA and protein expression of cyclooxygenase-2 (COX-2) were modulated in rats on PRD, providing evidence that COX-2, the inducible isoform of the enzyme, is involved in the management of colonic inflammation. Our results suggest that early-in-life exposure to PE might not protect against the development of IBD but enhances the extent of acute inflammation. Topics: Acute Disease; Animal Feed; Animals; Colitis; Colon; Cyclooxygenase 2; Diet; Disease Models, Animal; Female; Organ Size; Peroxidase; Phytoestrogens; Pregnancy; Pregnancy, Animal; Prenatal Exposure Delayed Effects; Rats; Rats, Wistar; RNA, Messenger; Time Factors; Trinitrobenzenesulfonic Acid; Uterus | 2008 |
Acute distal colitis impairs gastric emptying in rats via an extrinsic neuronal reflex pathway involving the pelvic nerve.
Patients with inflammatory bowel disease often present with abnormal gut motility away from the inflammatory site. We studied remote motility disturbances and their pathophysiology in a rat model of colitis.. Colitis was induced 72 h prior to experiments using trinitrobenzene sulphate (TNBS) instillation. Inflammation was verified using histology and myeloperoxidase (MPO) measurements. To assess gut motility, we determined gastric emptying, distal front and geometric centre (GC) of intestinal transit 30 min after intragastric administration of a semiliquid Evans blue solution. The effects of hexamethonium (20 mg/kg), capsaicin (125 mg/kg) and pelvic nerve section on colitis induced motility changes were evaluated. c-Fos expression was studied in the pelvic nerve dorsal root ganglion (DRG) S1.. Colitis reduced gastric emptying from 38.4 (3.6)% in controls to 22.7 (4.4)% in TNBS treated rats in the absence of local gastric inflammation. Colitis had no effect on the distal front or on the geometric centre of small intestinal transit. Hexamethonium reduced gastric emptying in controls to 26.3 (4.1)% but restored it to 35.8 (4.4)% in TNBS treated rats. Capsaicin significantly impaired gastric emptying in controls from 33.1 (5.2)% to 9.5 (3.3)% while this effect was less pronounced in TNBS treated rats (from 19.2 (2.3)% to 11.5 (3.8)%; NS). In TNBS treated rats, pelvic nerve section completely restored gastric emptying from 19.8 (5.3)% to 52.5 (6.3)% without any effect on gastric emptying in control rats. TNBS colitis induced de novo c-Fos expression in the DRG S1.. Experimental colitis in rats delays gastric emptying via a neuronal pathway involving pelvic afferent nerve hyperactivity. Topics: Acute Disease; Analgesics, Non-Narcotic; Animals; Capsaicin; Colitis; Ganglia, Spinal; Ganglionic Blockers; Gastric Emptying; Gastrointestinal Motility; Gastrointestinal Transit; Gastroparesis; Hexamethonium; Immunohistochemistry; Intestinal Mucosa; Male; Neural Pathways; Neurons; Pelvis; Peroxidase; Proto-Oncogene Proteins c-fos; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2007 |
Persistent alterations to enteric neural signaling in the guinea pig colon following the resolution of colitis.
Functional changes induced by inflammation persist following recovery from the inflammatory response, but the mechanisms underlying these changes are not well understood. Our aim was to investigate whether the excitability and synaptic properties of submucosal neurons remained altered 8 wk post-trinitrobenzene sulfonic acid (TNBS) treatment and to determine whether these changes were accompanied by alterations in secretory function in submucosal preparations voltage clamped in Ussing chambers. Mucosal serotonin (5-HT) release measurements and 5-HT reuptake transporter (SERT) immunohistochemistry were also performed. Eight weeks after TNBS treatment, colonic inflammation resolved, as assessed macroscopically and by myeloperoxidase assay. However, fast excitatory postsynaptic potential (fEPSP) amplitude was significantly increased in submucosal S neurons from previously inflamed colons relative to those in control tissue. In addition, fEPSPs from previously inflamed colons had a hexamethonium-insensitive component that was not evident in age-matched controls. AH neurons were hyperexcitable, had shorter action potential durations, and decreased afterhyperpolarization 8 wk following TNBS adminstration. Neuronally mediated colonic secretory function was significantly reduced after TNBS treatment, although epithelial cell signaling, as measured by responsiveness to both forskolin and bethanecol in the presence of tetrodotoxin, was comparable with control tissue. 5-HT levels and SERT immunoreactivity were comparable to controls 8 wk after the induction of inflammation, but there was an increase in glucagon-like peptide 2-immunoreactive L cells. In conclusion, sustained alterations in enteric neural signaling occur following the resolution of colitis, which are accompanied by functional changes in the absence of active inflammation. Topics: Action Potentials; Animals; Bethanechol; Body Weight; Cell Count; Colforsin; Colitis; Colon; Enteric Nervous System; Enteroendocrine Cells; Excitatory Postsynaptic Potentials; Glucagon-Like Peptide 2; Guinea Pigs; Male; Membrane Potentials; Neurons; Peptide YY; Peroxidase; Serotonin; Serotonin Plasma Membrane Transport Proteins; Submucous Plexus; Tetrodotoxin; Trinitrobenzenesulfonic Acid; Veratridine | 2007 |
Immunosuppressive activity of a new pteridine derivative (4AZA1378) alleviates severity of TNBS-induced colitis in mice.
Besides TNF, activated T cells play a central role in the pathogenesis of inflammatory bowel diseases such as Crohn's disease. New therapies are still awaited to cure these often debilitating diseases. Natural occurring pteridines such as tetrahydrobiopterin (BH4) and neopterin have been reported to have immune modulating activities. Starting from a pteridine scaffold library, we intended to select compounds with potent in vitro inhibitory effects on T cells and to evaluate in vivo efficacy of selected compounds on trinitrobenzenesulphonate (TNBS) colitis in mice. Compound 4AZA1378 was selected because it potently inhibits human T cell proliferation at low nM concentrations (IC50 4 nM) while an almost 50-fold higher concentration was needed to inhibit LPS-induced TNF production. Mice treated with 4AZA1378 had less severe signs of colitis after TNBS rectal administration, with a more rapid weight recovery. Myeloperoxidase (MPO) activity and intralesional cytokine production were lower in mice of the treated groups. Furthermore anti-TNBS antibody responses were completely inhibited by treatment with 4AZA1378. In conclusion, we identified a pteridine analogue 4AZA1378 with immunosuppressive activity and a strong remission-inducing effect in TNBS colitis, supporting further pre-clinical and clinical development of this novel molecule for treatment of inflammatory diseases. Topics: Animals; Colitis; Cytokines; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunosuppressive Agents; Jurkat Cells; Male; Mice; Mice, Inbred C57BL; Peroxidase; Pteridines; Reverse Transcriptase Polymerase Chain Reaction; T-Lymphocytes; Trinitrobenzenesulfonic Acid | 2007 |
Role of poly(ADP-ribose) glycohydrolase in the development of inflammatory bowel disease in mice.
Poly(ADP-ribose) is synthesized from nicotinamide adenine dinucleotide (NAD) by poly(ADP-ribose) polymerase 1 (PARP-1) and degraded by poly(ADP-ribose) glycohydrolase (PARG). The aim of the present study was to examine the role of PARG in the development of experimental colitis. To address this question, we used an experimental model of colitis, induced by dinitrobenzene sulfonic acid (DNBS). Mice lacking the functional 110-kDa isoform of PARG (PARG(110)KO mice) were resistant to colon injury induced by DNBS. The mucosa of colon tissues showed reduction of myeloperoxidase activity and attenuated staining for intercellular adhesion molecule 1 and vascular cell adhesion molecule 1. Moreover, overproduction of proinflammatory factors TNF-alpha and IL-1beta and activation of cell death signaling pathway, i.e., the FAS ligand, were inhibited in these mutant mice. Finally pharmacological treatment of WT mice with GPI 16552 and 18214, two novel PARG inhibitors, showed a significant protective effect in DNBS-induced colitis. These genetic and pharmacological studies demonstrate that PARG modulates the inflammatory response and tissue injury events associated with colitis and PARG may be considered as a novel target for pharmacological intervention for the pathogenesis. Topics: Animals; Benzenesulfonates; Cell Death; Colitis; Disease Models, Animal; Fas Ligand Protein; Glycoside Hydrolases; Inflammatory Bowel Diseases; Interleukin-1beta; Mice; Peroxidase; Tumor Necrosis Factor-alpha | 2007 |
Amelioration of dextran sulfate sodium-induced colitis in mice by oral administration of beta-caryophyllene, a sesquiterpene.
beta-Caryophyllene (BCP), a naturally occurring plant sesquiterpene, was examined for anti-inflammatory activity in a mouse model of experimental colitis induced by dextran sulfate sodium (DSS). Colitis was induced by exposing male BALB/c mice to 5% DSS in drinking water for 7 days. BCP in doses of 30 and 300 mg/kg was administered orally once a day, beginning concurrently with exposure to DSS. The body weight and colon length were measured, and histological damage and myeloperoxidase (MPO) activity as well as inflammatory cytokines were assessed in both serum and colonic tissue after 7 days of treatment with DSS. The DSS treatment damaged the colonic tissue, increased MPO activity and inflammatory cytokines, lowered the body weight, and shortened the length of the colon. Oral administration of BCP at 300 mg/kg significantly suppressed the shortening of colon length and slightly offset the loss of body weight. BCP treatment (300 mg/kg) also significantly reduced the inflammation of colon and reversed the increase in MPO activity that had been induced by exposure to DSS. Further, BCP significantly suppressed the serum level of IL-6 protein (a 55% reduction) as well as the level of IL-6 mRNA in the tissue. These results demonstrate that BCP ameliorates DSS-induced experimental colitis, and may be useful in the prevention and treatment of colitis. Topics: Animals; Body Weight; Colitis; Cytokines; Dextran Sulfate; Enzyme-Linked Immunosorbent Assay; Indicators and Reagents; Intestinal Mucosa; Male; Mice; Mice, Inbred BALB C; Organ Size; Peroxidase; Polycyclic Sesquiterpenes; Reverse Transcriptase Polymerase Chain Reaction; Sesquiterpenes | 2007 |
A comparative study of the preventative effects exerted by two probiotics, Lactobacillus reuteri and Lactobacillus fermentum, in the trinitrobenzenesulfonic acid model of rat colitis.
The intestinal anti-inflammatory effects of two probiotics isolated from breast milk, Lactobacillus reuteri and L. fermentum, were evaluated and compared in the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. Colitis was induced in rats by intracolonic administration of 10 mg TNBS dissolved in 50% ethanol (0.25 ml). Either L. reuteri or L. fermentum was daily administered orally (5 x 10(8) colony-forming units suspended in 0.5 ml skimmed milk) to each group of rats (n 10) for 3 weeks, starting 2 weeks before colitis induction. Colonic damage was evaluated histologically and biochemically, and the colonic luminal contents were used for bacterial studies and for SCFA production. Both probiotics showed intestinal anti-inflammatory effects in this model of experimental colitis, as evidenced histologically and by a significant reduction of colonic myeloperoxidase activity (P<0.05). L. fermentum significantly counteracted the colonic glutathione depletion induced by the inflammatory process. In addition, both probiotics lowered colonic TNFalpha levels (P<0.01) and inducible NO synthase expression when compared with non-treated rats; however, the decrease in colonic cyclo-oxygenase-2 expression was only achieved with L.fermentum administration. Finally, the two probiotics induced the growth of Lactobacilli species in comparison with control colitic rats, but the production of SCFA in colonic contents was only increased when L. fermentum was given. In conclusion, L. fermentum can exert beneficial immunomodulatory properties in inflammatory bowel disease, being more effective than L. reuteri, a probiotic with reputed efficacy in promoting beneficial effects on human health. Topics: Animals; Colitis; Colon; Diarrhea; Fatty Acids, Volatile; Feces; Female; Gastrointestinal Contents; Glutathione; Hydrogen-Ion Concentration; Inflammatory Bowel Diseases; Intestinal Mucosa; Limosilactobacillus fermentum; Limosilactobacillus reuteri; Models, Animal; Muscle, Skeletal; Organ Size; Peroxidase; Probiotics; Rats; Rats, Wistar; Spleen; Thymus Gland; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2007 |
G protein-coupled receptor kinase 6 controls chronicity and severity of dextran sodium sulphate-induced colitis in mice.
Infiltration of inflammatory cells into the colon plays an important role in the onset and course of inflammatory bowel disease. G-protein-coupled receptor kinase 6 (GRK6) is an intracellular kinase that regulates the sensitivity of certain G-protein-coupled receptors, including those involved in the migration of inflammatory cells. Therefore, it is hypothesised that GRK6 plays a role in determining the course of inflammation.. To analyse the role of GRK6 in the course of dextran sodium sulphate (DSS)-induced colitis.. Colitis was induced by administering 1% DSS in drinking water to GRK6(-/-), GRK6(+/-) and wild-type (WT) mice for 6 days. The severity of colitis was assessed on the basis of clinical signs, colon length and histology. Moreover, keratinocyte-derived chemokine (KC) levels, granulocyte infiltration, interleukin 1beta (IL1beta), CD4, CD8 and forkhead box protein P3 (FoxP3) expression in the colon were determined. In addition, regulatory T cell function in WT and GRK6(-/-) mice was analysed. The chemotactic response of granulocytes to colon culture supernatants was assessed using a transendothelial migration assay.. The severity of colitis was increased in GRK6(-/-) and GRK6(+/-) mice and was accompanied by increased KC levels and increased granulocyte infiltration. Moreover, the chemotactic response of GRK6(-/-) granulocytes to supernatants of colon cultures was enhanced. Interestingly, the WT mice completely recovered from colitis, whereas the GRK6(-/-) and GRK6(+/-) mice developed chronic colitis, which was accompanied by increased IL1beta and CD4 expression and decreased FoxP3 expression. Moreover, regulatory T cell function was impaired in the GRK6(-/-) mice.. The intracellular level of GRK6 is an important factor in determining the onset, severity and chronicity of DSS-induced colitis. Topics: Acute Disease; Animals; Chemotaxis, Leukocyte; Chronic Disease; Colitis; Dextran Sulfate; Disease Models, Animal; Eosinophil Peroxidase; Forkhead Transcription Factors; G-Protein-Coupled Receptor Kinases; Granulocytes; Male; Mice; Mice, Inbred C57BL; Peroxidase; Protein Serine-Threonine Kinases; Reverse Transcriptase Polymerase Chain Reaction; Severity of Illness Index; T-Lymphocytes, Regulatory; Tissue Culture Techniques | 2007 |
Role of blood- and tissue-associated inducible nitric-oxide synthase in colonic inflammation.
There is evidence that inducible nitric-oxide synthase (iNOS)-derived NO contributes to the pathophysiology of intestinal inflammation. The aims of this study were to assess the role of iNOS in the development of dextran sodium sulfate (DSS)-induced colonic inflammation and to define the contribution of tissue-specific iNOS expression to this inflammatory response. Study groups included: 1) wild-type (WT) mice; 2) WT=>WT bone marrow chimeras with normal iNOS function; 3) WT=>iNOS-/- chimeras (with functional blood cell iNOS, but iNOS-deficient tissue); 4) iNOS-/-=>WT chimeras (with iNOS-deficient blood cells, but normal tissue iNOS activity); and 5) iNOS-deficient mice. In WT mice and WT=>WT chimeras, DSS-induced colonic inflammation was characterized by bloody diarrhea and a high disease activity index. However, WT=>iNOS-/- and iNOS-/-=>WT chimeras and iNOS-/- mice exhibited an attenuated disease activity index, with parallel changes in histopathology. Colonic myeloperoxidase (MPO) was comparably elevated in DSS-treated WT mice (30.1+/-1.7) and WT=>WT chimeras (29.0+/-1), whereas MPO was significantly reduced in iNOS-/- mice and iNOS-/-=>WT chimeras (9.5+/-1.7 and 15.6+/-2.2, respectively). WT=>iNOS-/- chimeras exhibited the lowest MPO activity (3.7+/-0.6). Our findings implicate both blood cell- and tissue-derived iNOS in DSS-induced colonic inflammation, with tissue-associated iNOS making a larger contribution to the recruitment of inflammatory cells. Topics: Animals; Bone Marrow Transplantation; Breeding; Colitis; Colon; Dextran Sulfate; Inflammation; Mice; Mice, Knockout; Nitric Oxide Synthase Type II; Organ Specificity; Peroxidase; Transplantation Chimera | 2007 |
Sex steroid regulation of macrophage migration inhibitory factor in normal and inflamed colon in the female rat.
Sex steroids influence IBD symptoms. Macrophage migration inhibitory factor (MIF), a target of sex steroids in other inflammatory models, promotes interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha release in colitis. We investigated whether estradiol and progesterone influence MIF, IL-1beta, and TNF-alpha production in experimental colitis.. Colonic MIF, IL-1beta, and TNF-alpha levels were measured in cyclic and ovariectomized rats, with or without estradiol benzoate (EB) or progesterone (P) replacement. MIF distribution was assessed by immunohistochemistry. Cytokines, myeloperoxidase activity, macroscopic damage, and plasma corticosterone were assessed 24 hours after intrarectal trinitrobenzene sulfonic acid (TNBS), with and without neutralizing anti-MIF antibody. Effects of EB and P on myeloperoxidase activity and MIF concentration were also assessed at 7 days in dextran sulfate sodium-induced colitis.. Basal IL-1beta and TNF-alpha contents did not fluctuate during the estrous cycle, while MIF concentrations increased from estrus (estrogen dominance) to metestrus (P dominance; P < .05). EB and P treatment mimicked these effects in ovariectomized rats, and similarly altered MIF immunostaining. Progesterone dominance aggravated TNBS colitis in comparison with estrogen. Progesterone enhanced TNBS-induced MIF (P < .001) and TNF-alpha (P < .01) production, while EB decreased MIF (P < .01) and IL-beta levels (P < .01). Anti-MIF antibody prevented P-mediated up-regulation of TNF-alpha, improved TNBS colitis, and enhanced plasma corticosterone. At 7 days after dextran sulfate sodium, EB decreased myeloperoxidase activity and MIF concentration, while P had no effect.. Estrogen decreases while progesterone increases MIF production in the female rat colon. Changes in basal MIF contents may affect colon susceptibility to inflammation, by modulating TNF-alpha and IL-1beta production during early stages of colitis. Topics: Animals; Antibodies, Monoclonal; Colitis; Colon; Corticosterone; Dextran Sulfate; Disease Models, Animal; Estradiol; Estrous Cycle; Female; Gonadal Steroid Hormones; Immunohistochemistry; Interleukin-1beta; Intramolecular Oxidoreductases; Macrophage Migration-Inhibitory Factors; Ovariectomy; Peroxidase; Progesterone; Rats; Rats, Wistar; Severity of Illness Index; Sex Factors; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2007 |
CD40-CD40 ligand mediates the recruitment of leukocytes and platelets in the inflamed murine colon.
Although the CD40-CD40 ligand (CD40L) signaling pathway has been implicated in the pathogenesis of a variety of diseases, including inflammatory bowel disease, the nature of its contribution to intestinal inflammation remains poorly understood. The aim of this study was to determine whether CD40-CD40L contributes to the intestinal inflammatory response, tissue injury, and disease activity elicited by dextran sodium sulphate (DSS) through the modulation of leukocyte and platelet recruitment in the colonic microvasculature.. Wild-type (WT), CD40(-/-), and CD40L(-/-) mice were fed DSS drinking water. On day 6, intravital videomicroscopy was performed to monitor leukocyte and platelet recruitment in colonic venules, with measurements obtained for tissue myeloperoxidase and histology. CD40 expression on colonic endothelium was measured using the dual-radiolabeled antibody technique.. A comparison of the responses to DSS-induced colitis in CD40(-/-) and CD40L(-/-) mice to WT mice revealed a significant attenuation of disease activity and histologic damage, as well as profound reductions in the recruitment of adherent leukocytes and platelets in the mutant mice. Similar down-regulation of the blood cell recruitment responses to DSS was noted in WT mice treated with the CD40-CD40L pathway inhibitor Trapidil. CD40 expression in the colonic vasculature was greatly elevated during DSS-induced inflammation in WT mice, but not in CD40(-/-) mice.. These findings implicate CD40-CD40L in the pathogenesis of DSS-induced intestinal inflammation, and suggest that modulation of leukocyte and platelet recruitment by activated, CD40-positive endothelial cells in colonic venules may represent a major action of this signaling pathway. Topics: Animals; Blood Platelets; CD40 Antigens; CD40 Ligand; Cell Adhesion; Chemotaxis, Leukocyte; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Endothelium, Vascular; Leukocyte Rolling; Leukocytes; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Microscopy, Video; Peroxidase; Platelet Adhesiveness; Platelet Aggregation Inhibitors; Severity of Illness Index; Signal Transduction; Time Factors; Trapidil; Venules | 2007 |
Chronic administration of galanin attenuates the TNBS-induced colitis in rats.
Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disorder considered as a consequence of an aberrant response of the immune system to luminal antigens. Numerous groups of agents are being evaluated as novel therapeutic approaches for its treatment; in this way, different peptides have emerged as potential candidates. Galanin is an active neuropeptide distributed in the central and periphery nervous systems although it has been also described having important autocrine and paracrine regulatory capacities with interesting inflammatory and immune properties. In this line, we have observed that galanin treatment has a significant preventive effect in the experimental trinitrobenzensulfonic acid (TNBS) acute model of inflammatory colitis. The aim of the present study was to investigate intensively the role played by the peptide in the evolution of the inflammatory pathology associated to IBD. Galanin (5 and 10 microg/kg/day) was administered i.p., daily, starting 24 h after TNBS instillation, and continuing for 14 and 21 days. The lesions were blindly scored according to macroscopic and histological analyses and quantified as ulcer index. The results demonstrated that chronic administration of galanin improved the colon injury than the TNBS induced. The study by Western-blotting of the expression of nitric oxide inducible enzyme (iNOS), as well as the total nitrite production (NO) assayed by Griess-reaction, showed significant reduction associated with peptide administration. The number of mast cells was also identified in histological preparations stained with toluidine blue and the results showed that samples from galanin treatment, mostly at 21 days, had increased the number of these cells and many of them had a degranulated feature. In conclusion, chronic administration of galanin is able to exert a beneficial effect in the animal model of IBD assayed improving the reparative process. Participation of nitric oxide pathways and mucosal mast cells can not be discarded. Topics: Animals; Blotting, Western; Colitis; Cyclooxygenase 2; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Galanin; Injections, Intraperitoneal; Male; Mast Cells; Nitric Oxide Synthase Type II; Nitrites; Peroxidase; Rats; Rats, Wistar; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2007 |
PARP inhibition reduces acute colonic inflammation in rats.
Poly(ADP-ribose) polymerases (PARP) comprise a family of enzymes which catalyse poly(ADP-ribosyl)ation of DNA-binding proteins. Multiple researches indicate the importance of PARP in promoting cell recruitment and thereby inducing organ injury in various forms of inflammation, such as colitis. We have evaluated the effects of two PARP inhibitors, nicotinamide and 1,5-dihydroxyisoquinoline, in acute colitis induced by trinitrobenzensulfonic acid (TNBS) in rats. Nicotinamide (20-40 mg/kg) and 1,5-dihydroxyisoquinoline (4-8 mg/kg) were administered 48, 24 and 1 h prior to the induction of colitis as well as 24 h later. 48 h after colitis induction the lesions were blindly scored and quantified as ulcer index. Histological study and colonic inflammation were assessed by gross appearance and myeloperoxidase (MPO) activity. Prostaglandin E2 (PGE2) synthesis and, cyclooxygenase-1 and cyclooxygenase-2 expressions by Western blotting and immunohistochemistry were also performed. Inflammation following TNBS induction was characterized by increased colonic wall thickness, oedema, diffuse inflammatory cells infiltration in the mucosa and necrosis. Furthermore, increased MPO activity, cyclooxygenase-2 expression and PGE2 synthesis were significantly augmented after TNBS instillation. On the contrary, treatment with 1,5-dihydroxyisoquinoline significantly reduced the degree of colon injury and also caused a substantial reduction in the rise in MPO activity, in the increase of staining for cyclooxygenase-2, as well as in the up-regulation of PGE2 caused by TNBS in the colon. Although nicotinamide significantly did not reduce macroscopic damage, it decreased both MPO activity and PGE2 colonic levels. In conclusion, we demonstrated that PARP inhibition can exert beneficial effects in experimental colitis and may, therefore, be useful in the treatment of ulcerative colitis. Topics: Acute Disease; Animals; Anti-Inflammatory Agents; Colitis; Colon; Cyclooxygenase 1; Cyclooxygenase 2; Dinoprostone; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Gastrointestinal Agents; Isoquinolines; Membrane Proteins; Niacinamide; Peroxidase; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Rats; Rats, Wistar; Time Factors; Trinitrobenzenesulfonic Acid | 2007 |
Sinomenine attenuates 2, 4, 6-trinitrobenzene sulfonic acid-induced colitis in mice.
Sinomenine is a pure alkaloid extracted from the Chinese medical plant Sinomenium acutum. It was demonstrated that sinomenine had anti-inflammatory and immunosuppressive effects in the previous studies. The aim of the present study was to evaluate therapeutic effects of sinomenine on 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) induced colitis in mice. Two hours following colonic instillation of TNBS, sinomenine with several doses (30, 100, 200 mg/kg) was given by gastric gavage once daily for 7 days. Comparing with the saline-treated mice with TNBS-induced colitis, sinomenine (100 mg/kg and 200 mg/kg)-treated mice with TNBS-induced colitis were shown improvements of weight loss, macroscopic score, histological score, and myeloperoxidase activity. Moreover, treatments with sinomenine (100 mg/kg and 200 mg/kg) decreased the up-regulated mRNA and protein levels of tumour necrosis factor-alpha(TNF-alpha) and interferon-gamma (IFN-gamma) caused by TNBS. Our findings suggest that sinomenine attenuates TNBS-induced colitis in mice and the therapeutic mechanism might be related to the reduction of up-regulated colonic TNF-alpha and IFN-gamma production caused by TNBS. Topics: Animals; Anti-Inflammatory Agents; Body Weight; Colitis; Colon; Enzyme-Linked Immunosorbent Assay; Female; Interferon-gamma; Mice; Mice, Inbred BALB C; Morphinans; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2007 |
PPARbeta/delta protects against experimental colitis through a ligand-independent mechanism.
Peroxisome proliferator-activated receptors (PPARs) beta/delta and gamma have overlapping roles in the negative regulation of inflammatory response genes. Ligand activation of PPARgamma protects against experimental colitis in mice. PPARbeta/delta can negatively regulate inflammation and is highly expressed in the epithelial cells of the colon, therefore PPARbeta/delta may also have a role in experimental colitis. In these studies, colitis was induced by dextran sodium sulfate (DSS) treatment in wild-type and PPARbeta/delta-null mice, with and without the PPARbeta/delta specific ligand GW0742. PPARbeta/delta-null mice exhibited increased sensitivity to DSS-induced colitis, as shown by marked differences in body weight loss, colon length, colonic morphology, myeloperoxidase activity and increased expression of mRNAs encoding the inflammatory markers interferon gamma, tumor necrosis factor-alpha, and interleukin-6 compared to similarly treated wild-type mice. Interestingly, these differences were not affected by ligand activation of PPARbeta/delta in either genotype. These studies demonstrate that PPARbeta/delta expression in the colonic epithelium inhibits inflammation and protects against DSS-induced colitis through a ligand-independent mechanism. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Disease Progression; Enterocytes; Female; Gene Expression; Interferon-gamma; Interleukin-6; Ligands; Mice; Mice, Inbred C57BL; Peroxidase; Plasma Substitutes; Polymerase Chain Reaction; PPAR delta; PPAR-beta; RNA, Messenger; Severity of Illness Index; Thiazoles; Tumor Necrosis Factor-alpha | 2007 |
Helminth infection enhances disease in a murine TH2 model of colitis.
There is convincing evidence from animal and human studies that infection with parasitic helminths can alleviate the histopathology and symptoms of colitis. Here the ability of the rat tapeworm Hymenolepis diminuta to affect the course of oxazolone-induced colitis (a TH2 model) was assessed.. Mice were infected with H diminuta and 8 days later they received oxazolone (3 mg in 50% EtOH, intrarectal). On autopsy (3 or 7 days postoxazolone), disease severity was assessed by macroscopic clinical scores, histologic damage scores, myeloperoxidase and eosinophil peroxidase activity, and cytokine synthesis.. As gauged by all markers of gut function, infection with H diminuta caused a significant exacerbation of oxazolone-induced colitis. Indeed, while mice receiving oxazolone only began to recover approximately 3-4 days posttreatment, the cotreated group continued to deteriorate. Helminth infection, independent of oxazolone administration, enhanced IL-4, IL-5, IL-10, and IL-13 production from in vitro stimulated immune cells and evoked increases in colonic eosinophil peroxidase of cotreated mice. Finally, while knockout of natural killer (NK) and NK-T cells by administration of a neutralizing NK1.1 antibody reduced the inflammation in oxazolone and oxazolone + H diminuta-treated animals, mice in the latter group still displayed significant colitis.. We have shown that H diminuta infection is beneficial in other models of colitis. The current data is presented as a caveat to the position that parasitic helminths in general can be considered as a therapy for heterogeneous inflammatory disorders without careful analysis of the immunologic basis of the condition. Topics: Adjuvants, Immunologic; Animals; Antigens, Ly; Antigens, Surface; Biomarkers; Colitis; Colon; Disease Models, Animal; Disease Progression; Enzyme-Linked Immunosorbent Assay; Eosinophil Peroxidase; Follow-Up Studies; Hymenolepiasis; Hymenolepis diminuta; Interleukin-10; Interleukin-13; Interleukin-4; Interleukin-5; Killer Cells, Natural; Lectins, C-Type; Male; Mice; Mice, Inbred BALB C; NK Cell Lectin-Like Receptor Subfamily B; Oxazolone; Peroxidase; Survival Rate | 2007 |
Prebiotic and synbiotic fructooligosaccharide administration fails to reduce the severity of experimental colitis in rats.
Opposing effects of the prebiotic, fructooligosaccharide, have been reported in experimental colitis. We compared the effects of the prebiotic, fructooligosaccharide, alone and in synbiotic combination with Lactobacillus fermentum BR11, on the development of dextran sulfate sodium-induced colitis in rats. Rats consumed an 18 percent casein-based diet or diet supplemented with 6 percent fructooligosaccharide or maltodextrin for 14 days. The synbiotic group was gavaged 1 ml of L. fermentum BR11 (1x10(9) cfu/ml) twice daily. From Days 7 to 14, colitis was induced via 3 percent dextran sulfate sodium in drinking water. Disease activity was assessed daily, and at killing, gastrointestinal organs were measured, weighed, and examined by quantitative histology, proliferating cell nuclear antigen immunohistochemistry, and colonic myeloperoxidase activity. Administration of dextran sulfate sodium resulted in an increased colitic disease activity, and an increased colon and cecum weight compared with normal controls. Colon and cecum weights were further increased in dextran sulfate sodium+fructooligosaccharide (colon: 19 percent; cecum: 48 percent) and dextran sulfate sodium+fructooligosaccharide/L. fermentum BR11-treated rats (16 and 62 percent) compared with dextran sulfate sodium+vehicle-treatment. Dextran sulfate sodium+fructooligosaccharide-treated rats displayed an 81 percent increase in colonic myeloperoxidase activity compared with dextran sulfate sodium-treated controls. Histologic damage severity scores increased in dextran sulfate sodium+vehicle, dextran sulfate sodium+fructooligosaccharide, and dextran sulfate sodium+fructooligosaccharide/L. fermentum BR11-treated rats compared with normal controls (P<0.05). Crypt depth increased in all treatments compared with normal controls (P<0.01). No protection from dextran sulfate sodium-colitis was accorded by fructooligosaccharide alone or in synbiotic combination with L. fermentum BR11, whereas fructooligosaccharide actually increased some indicators of colonic injury. Topics: Administration, Oral; Animals; Cell Proliferation; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Limosilactobacillus fermentum; Male; Oligosaccharides; Peroxidase; Probiotics; Rats; Rats, Sprague-Dawley; Severity of Illness Index; Treatment Failure | 2007 |
Curcumin prevents the development of dextran sulfate Sodium (DSS)-induced experimental colitis.
Curcumin is a phenolic natural product isolated from the rhizome of Curcuma longa (turmeric). We evaluated the effects of curcumin on the development of dextran sulfate sodium (DSS)-induced experimental colitis. BALB/c mice were fed a chow containing either 3.5% (wt/wt) DSS or 3.5% DSS + 2.0% (wt/wt) curcumin. The body weight loss was more apparent in DSS-treated mice than in DSS + curcumin-treated mice. The disease activity index, histological colitis score, and MPO activity were all significantly higher in DSS-treated mice than in DSS plus curcumin-treated mice. Microscopically, mucosal edema, cellular infiltration, and epithelial disruption were much more severe in DSS-treated mice than in DSS + curcumin-treated mice. In DSS + curcumin-treated mice, NF-kappaB activation was blocked in the mucosa. In conclusion, the development of DSS-induced colitis was significantly attenuated by curcumin. Being a nontoxic natural dietary product, curcumin could be useful in treatment of IBD patients. Topics: Animals; Antineoplastic Agents; Colitis; Colon; Curcumin; Dextran Sulfate; Disease Models, Animal; Immunohistochemistry; Male; Mice; Mice, Inbred BALB C; Peroxidase; Plasma Substitutes | 2007 |
Erdosteine prevents colonic inflammation through its antioxidant and free radical scavenging activities.
After intracolonic administration of trinitrobenzene sulphonic acid (TNBS), Sprague-Dawley rats were treated orally either with saline or erdosteine (100 mg/kg per day), a sulfhydryl-containing antioxidant, for 3 days. On the 4th day, rats were decapitated and distal colon was removed for the macroscopic and microscopic damage scoring, for the measurement of malondialdehyde (MDA), glutathione (GSH) and collagen levels, myeloperoxidase (MPO) activity, luminol and lucigenin chemiluminescence (CL) and DNA fragmentation. Lactate dehydrogenase (LDH) activity, tumor necrosis factor-alpha, interleukin (IL)-1beta, IL-6, and antioxidant capacity were assayed in blood samples. Colitis caused significant increases in the colonic CL values, macroscopic and microscopic damage scores, MDA and collagen levels, MPO activity and DNA fragmentation, along with a significant decrease in tissue GSH level. Similarly, serum cytokines and LDH were elevated in the saline-treated colitis group as compared with the control group. On the other hand, erdosteine treatment reversed all these biochemical indices, and histopathologic alterations induced by TNBS, suggesting that erdosteine protects the colonic tissue via its radical scavenging and antioxidant activities. Topics: Acridines; Animals; Antioxidants; Colitis; Collagen; Colon; Disease Models, Animal; DNA Fragmentation; Enzyme-Linked Immunosorbent Assay; Expectorants; Female; Free Radical Scavengers; Glutathione; Luminescence; Luminol; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Severity of Illness Index; Thioglycolates; Thiophenes; Trinitrobenzenesulfonic Acid | 2007 |
In vivo treatment with the herbal phenylethanoid acteoside ameliorates intestinal inflammation in dextran sulphate sodium-induced colitis.
Recently we demonstrated that in inflammatory bowel disease (IBD) macrophage-oxidative burst activity is increased and NADPH oxidase mRNA is induced. The herbal phenylethanoid acteoside isolated from Plantago lanceolata L. was shown to exhibit anti-oxidative potential. Using the dextran sulphate sodium (DSS)-induced colitis model, in this study we have assessed whether systemic application of acteoside affects colitis. Colitis was induced by DSS in Balb/c mice. Treatment with acteoside (120, 600 microg/mouse/day) was performed intraperitoneally. The colon lengths were determined. Colonic tissue was scored histologically (max. score 8) by a blinded investigator. T cells isolated from mesenteric lymph nodes (MLN) were stimulated with anti-CD3 antibody in the presence of interleukin (IL)-2 (final concentration 10 U/ml). After incubation for 24 h, IL-1beta, IL-6, IL-12 tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma levels in supernatants were analysed by the beadlyte cytokine detection system. Histological scoring of colonic tissue revealed that application of acteoside was followed by a significantly improved histological score. In acute colitis the histological score was 3.2 with acteoside versus 5.2 with phosphate-buffered saline (PBS) (P < 0.02). In chronic colitis both 120 microg (3.3 versus 5.2) or 600 microg acteoside (3.0 versus 5.2) significantly ameliorated colitis (both P < 0.02). Stimulated MLN from mice with chronic DSS-induced colitis treated with acteoside showed a significant down-regulation of IFN-gamma secretion (195 pg/ml with 600 microg acteoside versus 612 pg/ml with PBS, P < 0.02). Inhibition of oxidative burst activity with acteoside reduced mucosal tissue damage in DSS colitis and could be a therapeutic alternative for IBD treatment. Further studies of this agent are warranted. Topics: Acute Disease; Animals; Antioxidants; Chronic Disease; Colitis; Colon; Cytokines; Dextran Sulfate; Enzyme-Linked Immunosorbent Assay; Female; Glucosides; Inflammation Mediators; Intestinal Mucosa; Lymph Nodes; Macrophages; Mice; Mice, Inbred BALB C; Peroxidase; Phenols; Respiratory Burst; Weight Loss | 2007 |
Protective effect of melatonin in acetic acid induced colitis in rats.
Possible protective effects of exogenous melatonin on colonic inflammation were studied in rats. Colitis was induced by intracolonic (i.c.) instillation of 4% acetic acid (AA) and the resulting injury was assessed after 1 and 48 hr. Diffuse hyperemia and bleeding with erosions and ulcerations were observed in the colons of vehicle-treated rats. Melatonin administered in doses of 5 and 10 mg/kg reduced significantly the extent of gross mucosal damage after intraperitoneal as well as i.c. dosing. The inflammation induced increase in colonic wet weight was also reduced by melatonin treatment. In the early phase of colonic inflammation (60 min), melatonin partly prevented the decrease of reduced glutathione (GSH) content and limited lysosomal enzyme, N-acetyl-glucosaminidase and cathepsin D, activities induced by AA, with no changes in proteins or acid phosphatase activity. Increase of myeloperoxidase activity (MPO) caused by colonic inflammation was prevented by melatonin given i.c. As observed 48 hr after AA exposure, there was no difference between the effect of vehicle and melatonin on the content of GSH. Colitis did not influence the melatonin content of the colon. After administration of exogenous melatonin, plasma, pineal and gut melatonin tended to increase. The results indicate that melatonin participates in various defense mechanisms against colonic inflammatory processes by preserving the important endogenous antioxidant reserve of GSH, by preventing lysosomal enzyme disruption, by inhibiting enhanced MPO activity, thus reducing the extent of colonic damage, mainly in the early phase of colitis. Topics: Acetic Acid; Animals; Colitis; Colon; Glutathione; Male; Melatonin; Peroxidase; Rats; Rats, Wistar | 2007 |
Effects of the probiotic formulation VSL#3 on colitis in weanling rats.
Only a few studies have used models of inflammatory bowel disease (IBD) with weanling animals. Previously, the effects of probiotics have not been assessed in such IBD models. The objectives of our study were 2-fold: to establish a suitable model of dextran sulfate sodium (DSS)-induced colitis in weanling rats and to determine the effects of the probiotic formulation VSL#3 on DSS-induced colitis in weanling animals.. Rats were weaned on postnatal day 21 and administered 2%, 2.5%, or 3% (wt/vol) DSS in drinking water. In subsequent experiments, newly weaned animals were administered vehicle or VSL#3 (0.06, 0.6, or 6 mg) by orogastric gavage. These treatments were given to animals maintained on water (postnatal days 21-28) and then on DSS (postnatal days 28-35). Disease activity indices were determined on a routine basis. On day 35, rats were euthanized. The total colon length was determined. Other parameters of colitis were measured from the distal colon. These parameters included myeloperoxidase (MPO), interleukin (IL)-1beta, inhibitory kappaB-alpha (IkappaB-alpha), and histological assessment of crypt damage and inflammation.. DSS 2% was optimal for inducing colitis in weanling rats without significant morbidity. VSL#3 treatments improved various parameters of 2% DSS-induced colitis in weanling rats. The 0.6- and 6-mg doses of VSL#3 were most effective for attenuating this colitis.. The probiotic formulation VSL#3 improved DSS-induced colitis in weanling rats. This improvement of colitis involved changes in colonic IkappaB-alpha, IL-1beta, and MPO, which are suggestive of immune modulation by VSL#3. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Female; I-kappa B Proteins; Inflammatory Bowel Diseases; Interleukin-1beta; Male; NF-KappaB Inhibitor alpha; Peroxidase; Probiotics; Rats; Rats, Wistar; Weaning | 2007 |
The role of PPARgamma on restoration of colonic homeostasis after experimental stress-induced inflammation and dysfunction.
Psychological stress has been implicated in the clinical course of several gastrointestinal diseases, but the mechanisms implicated and the effects of stress on the normal colon are not yet fully understood.. Male Wistar rats were exposed to various immobilization periods as a stress paradigm. Colon was processed to assess myeloperoxidase activity, nitric oxide synthase 2, cyclooxygenase 2, and peroxisome proliferator-activated receptor gamma (PPARgamma) expression and production of prostaglandins. Colonic permeability, bacterial translocation, tight junctions ultrastructure, and immunoglobulin (Ig) A levels were also evaluated.. Exposure to acute (6 hours) immobilization stress produced an increase in myeloperoxidase activity and nitric oxide synthase 2 and cyclooxygenase 2 expression. All these parameters remained increased after 5 days of repeated stress exposure, showing a trend to normalize after 10 days. Levels of the anti-inflammatory eicosanoid 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) and expression of PPARgamma run parallel with these changes. Colonic epithelial barrier was altered after stress exposure, and a significant decrease in colonic IgA levels after acute stress exposure was observed. Pretreatment with PPARgamma agonists 15d-PGJ(2) and rosiglitazone prevented colonic inflammation and barrier dysfunction as well as the decrease of IgA production induced after acute stress; PPARgamma specific antagonist T0070907 reverted these effects.. Activation of PPARgamma in rat colon in vivo seems to counteract colonic inflammation and dysfunction induced by stress. On the other hand, PPARgamma ligands may be therapeutically useful in conditions in which inflammation and barrier dysfunction takes place in colon after exposure to stress. Topics: Animals; Bacterial Translocation; Benzamides; Colitis; Colon; Corticosterone; Cyclooxygenase 2; Gene Expression Regulation, Enzymologic; Homeostasis; Intestinal Absorption; Ligands; Male; Nitric Oxide Synthase Type II; Peroxidase; PPAR gamma; Prostaglandin D2; Pyridines; Rats; Rats, Wistar; Restraint, Physical; Rosiglitazone; Stress, Physiological; Thiazolidinediones | 2007 |
Inhibition of adenosine deaminase attenuates inflammation in experimental colitis.
Adenosine modulates the immune system and inhibits inflammation via reduction of cytokine biosynthesis and neutrophil functions. Drugs able to prevent adenosine catabolism could represent an innovative strategy to treat inflammatory bowel disorders. In this study, the effects of 4-amino-2-(2-hydroxy-1-decyl)pyrazole[3,4-d]pyrimidine (APP; novel adenosine deaminase inhibitor), erythro-9-(2-hydroxy-3-nonyl)adenine hydrochloride (EHNA; standard adenosine deaminase inhibitor), and dexamethasone were tested in rats with colitis induced by 2,4-dinitrobenzenesulfonic acid (DNBS). DNBS-treated animals received APP (5, 15, or 45 micromol/kg), EHNA (10, 30, or 90 micromol/kg), or dexamethasone (0.25 micromol/kg) i.p. for 7 days starting 1 day before colitis induction. DNBS caused bowel inflammation associated with decrease in food intake and body weight. Animals treated with APP or EHNA, but not dexamethasone, displayed greater food intake and weight gain than inflamed rats. Colitis induced increment in spleen weight, which was counteracted by all test drugs. DNBS administration was followed by macroscopic and microscopic inflammatory colonic alterations, which were ameliorated by APP, EHNA, or dexamethasone. In DNBS-treated rats, colonic myeloperoxidase, malondialdehyde, and tumor necrosis factor (TNF)-alpha levels as well as plasma TNF-alpha and interleukin-6 were increased. All test drugs lowered these phlogistic indexes. Inflamed colonic tissues displayed an increment of inducible nitric-oxide synthase mRNA, which was unaffected by APP or EHNA, but reduced by dexamethasone. Cyclooxygenase-2 expression was unaffected by DNBS or test drugs. These findings indicate that 1) inhibition of adenosine deaminase results in a significant attenuation of intestinal inflammation and 2) the novel compound APP is more effective than EHNA in reducing systemic and intestinal inflammatory alterations. Topics: Adenine; Adenosine Deaminase; Adenosine Deaminase Inhibitors; Animals; Benzenesulfonates; Body Weight; Colitis; Colon; Cyclooxygenase 2; Dexamethasone; Eating; Enzyme Inhibitors; Gene Expression Regulation, Enzymologic; Interleukin-6; Intestinal Mucosa; Male; Malondialdehyde; Nitric Oxide Synthase Type II; Organ Size; Peroxidase; Pyrazoles; Pyrimidines; Rats; Rats, Sprague-Dawley; Spleen; Tumor Necrosis Factor-alpha | 2007 |
PECAM-1 (CD 31) mediates transendothelial leukocyte migration in experimental colitis.
Transendothelial migration of circulating leukocytes into the colonic wall is a key step in the development of the inflammatory infiltrate in inflammatory bowel disease (IBD). The platelet-endothelial cell adhesion molecule-1 PECAM-1 (CD31) is expressed in the tight junction area of endothelial cells, where it is supposed to support the transmigration process. The aim of this study was to determine the role of PECAM-1 in experimental IBD and to show whether blockade of PECAM-1 has therapeutic effects. Chronic colitis was induced in female BALB/c mice by cyclic oral administration of dextran sodium sulfate (DSS) 3% (wt/vol). Expression of PECAM-1 was visualized by immunohistochemistry. In the treatment group animals received 1 mg/kg anti-PECAM-1 (2H8) ip daily starting on day 26. On day 30 leukocyte adhesion and migration was measured during N(2)O-isoflurane anesthesia in the distal colon by intravital microscopy. Disease activity index (DAI), histology, and MPO levels were compared with healthy and diseased controls. PECAM-1 was expressed in colitic mice. Chronic DSS colitis was characterized by a marked increase in rolling, adherent, and transmigrated leukocytes compared with healthy controls. Immunoblockade of PECAM-1 reduced leukocyte transmigration significantly and also diminished leukocyte rolling and sticking in an indirect manner. It also resulted in a significantly diminished DAI and MPO levels, as well as an amelioration of the histological inflammation score. PECAM-1 plays an important role in transendothelial leukocyte migration in DSS colitis. PECAM-1 could be a novel target for antibody-based treatment in IBD. Topics: Animals; Anti-Inflammatory Agents; Antibodies, Monoclonal; Chronic Disease; Colitis; Dextran Sulfate; Disease Models, Animal; Endothelial Cells; Female; Gastrointestinal Agents; Leukocyte Rolling; Leukocytes; Mice; Mice, Inbred BALB C; Microscopy, Video; Peroxidase; Platelet Endothelial Cell Adhesion Molecule-1 | 2007 |
The PPARgamma agonist rosiglitazone impairs colonic inflammation in mice with experimental colitis.
Various animal models showed that peroxisome proliferator-activated receptor (PPAR)gamma agonists, when given as a gavage shortly preceding colitis induction, protect against inflammatory bowel disease (IBD). We have examined the effects of 16 days rosiglitazone treatment via the diet prior to dextran sodium sulphate (DSS)-induced colitis in mice. After 7 days DSS in the drinking water, rosiglitazone-fed mice had lost significantly more weight than control mice. Rosiglitazone-treated mice had more diarrhea, weight of colon and spleen were increased, and length of colon was decreased. Histology showed that rosiglitazone-treated mice had more severe colitis, mainly caused by more ulceration, crypt loss, and edema. Immunofluorescence showed a loss of tight junction structure Zonula Occludens protein 1 (ZO-1) in colons of rosiglitazone-treated mice as compared to control mice. Also, serum amyloid P component (SAP) concentrations in plasma were increased. However, concentrations of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma in colon homogenates, and TNF-alpha in spleen homogenates were significantly decreased, whereas interleukin (IL)-10 in spleen homogenates was increased. Other cytokines (IL-2, IL-4, IL-6, IL-12p70 and monocyte chemotactic protein (MCP)-1) and myeloperoxidase (MPO) concentrations showed no differences. In conclusion, 16 days pretreatment with rosiglitazone impaired DSS-induced colitis in mice. Topics: Animals; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Female; Membrane Proteins; Mice; Mice, Inbred C57BL; Peroxidase; Phosphoproteins; PPAR gamma; Rosiglitazone; Serum Amyloid P-Component; Spleen; Thiazolidinediones; Zonula Occludens-1 Protein | 2007 |
Decreased drug penetration in inflamed tissue related to changed mucosal metabolism in experimental colitis.
Pathophysiologic changes in mucosal protein expression inflammatory bowel disease (IBD) may affect drug concentration in mucosal tissue making it highly relevant to drug dose at the site of action and subsequently for success of the therapy. Tissue samples from an experimental colitis rat model were mounted in Ussing chambers and intratissue concentrations of diverse compounds were quantified. Studies with healthy versus colitis tissue samples and respective microsomal fractions made it possible to assess the involvement of P-glycoprotein (P-gp) and cytochrome P450 3A (CYP3A) on tissue penetration behavior. P-gp-related efflux was slightly increased for colitis tissue. Metabolism studies exhibited higher tacrolimus and testosterone mucosal metabolism in inflamed tissue. However, similar metabolic activity was observed for healthy and colitis groups with equivalent CYP3A expression levels in respective microsome fractions. Severity of colitis as determined by myeloperoxidase activity was found to have linear correlation to changes in tacrolimus degradation (R2 = 0.8299). It is hypothesized that increased drug metabolism is dependent on the number of cells infiltrating inflamed tissue. A dominant contribution of immune-related cells to observed variations in mucosal drug metabolism has been determined. This observed pathophysiologic mechanism may have a significant influence on available drug concentrations at the inflammation site, thus modifying anti-inflammatory efficiency of the therapy. Topics: Animals; ATP Binding Cassette Transporter, Subfamily B, Member 1; Colitis; Cytochrome P-450 CYP3A; Immunosuppressive Agents; Intestinal Mucosa; Male; Microsomes; Peroxidase; Rats; Rats, Wistar; Severity of Illness Index; Tacrolimus; Testosterone | 2007 |
Hyperthermia ameliorates 2,4,6-trinitrobenzene sulphonic acid-induced colitis in rats: the role of heat shock proteins.
Hyperthermia is known to protect against cellular injury through the expression of heat shock proteins. In this study, the therapeutic effects of hyperthermia on experimental colitis in the rat were evaluated.. Male Wistar rats were given a single intracolonic injection of 2,4,6-trinitrobenzene sulphonic acid (TNBS). Hyperthermia was induced in anesthetized rats by placing them in a temperature-controlled water bath. We started the hyperthermic treatment on the day after the enema. The severity of colitis was evaluated pathologically, and the activities of tissue myeloperoxidase were measured 6 days after the induction of colitis. Furthermore, cytokines, and hyperthermia-induced heat shock proteins in colonic mucosa were detected by enzyme-linked immunosorbent assay and Western blotting. We also investigated the effects of geranylgeranylacetone and zinc protoporphyrin IX on the therapeutic effect of hyperthermia.. Hyperthermia significantly improved the macroscopic scores of colitis. The TNBS-induced increases in the activities of myeloperoxidase in the colonic tissue were blunted significantly in hyperthermia-treated animals. Furthermore, hyperthermia attenuated increases in cytokine-induced neutrophil chemoattractants-1 and tumor necrosis factor-alpha in the colon. Furthermore, hyperthermia induced the production of heat shock proteins in rat colonic mucosa, and the combination of geranylgeranylacetone with hyperthermia further induced the heat shock protein HSP70, which resulted in further improvement of TNBS-induced colitis. On the other hand, the combination of zinc protoporphyrin IX with hyperthermia attenuated the therapeutic effect of hyperthermia.. Hyperthermia ameliorates TNBS-induced colitis in rats through the expression of HSP70 and HO-1. It is postulated that hyperthermia may be useful for the treatment of inflammatory bowel diseases. Topics: Animals; Anti-Ulcer Agents; Body Temperature; Colitis; Colon; Diterpenes; Enzyme Inhibitors; Fever; Heat-Shock Proteins; Male; Peroxidase; Protoporphyrins; Random Allocation; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2007 |
Vagus nerve integrity and experimental colitis.
Previous studies have identified a counterinflammatory vagal reflex in the context of endotoxic shock. We have extended this observation to show that the vagus confers protection against acute (5 days) colitis induced by dextran sodium sulfate (DSS) or by dinitrobenzene sulfonic acid (DNBS). We have shown that this is mediated via macrophages and involves the suppression of proinflammatory cytokines. In this study, we have examined whether the vagal integrity confers long-lasting protection by studying DNBS- and DSS-induced inflammatory responses in the colon at 9 to 61 days postvagotomy. The integrity of vagotomy was confirmed at all time points using CCK-induced satiety. As previously described in a DNBS and DSS model, vagotomy associated with the pyloroplasty increased all indices of inflammation. Vagotomy increased the disease activity index as well as the macroscopic and histological scores by 75 and 41%, respectively. In addition, myeloperoxidase (MPO) activity, serum levels of C-reactive protein (CRP), and colonic tissue levels of proinflammatory cytokine increased when colitis was induced 9 days postvagotomy. However, these increases in inflammatory indices were substantially diminished in mice with colitis induced 21, 33, and 61 days postvagotomy. This was accompanied by an increased production of interleukin-10, transforming growth factor-beta, Forkhead Box P3 (FOXP3) staining in colonic tissue, and serum corticosterone. These findings indicate that although vagal integrity is an important protective factor, other counterinflammatory mechanisms come into play if vagal integrity is compromised beyond 2 wk. Topics: Animals; C-Reactive Protein; Colitis; Colon; Corticosterone; Dextran Sulfate; Dinitrofluorobenzene; Disease Models, Animal; Eating; Forkhead Transcription Factors; Interleukins; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reflex; Severity of Illness Index; Sincalide; T-Lymphocytes, Regulatory; Time Factors; Transforming Growth Factor beta; Vagotomy, Truncal; Vagus Nerve | 2007 |
Colon-specific delivery of 5-aminosalicylic acid from chitosan-Ca-alginate microparticles.
Chitosan-Ca-alginate microparticles for colon-specific delivery and controlled release of 5-aminosalicylic acid after peroral administration were prepared using spray drying method followed by ionotropic gelation/polyelectrolyte complexation. Physicochemical characterization pointed to the negatively charged particles with spherical morphology having a mean diameter less than 9 microm. Chitosan was localized dominantly in the particle wall, while for alginate, a homogeneous distribution throughout the particles was observed. (1)H NMR, FTIR, X-ray and DSC studies indicated molecularly dispersed drug within the particles with preserved stability during microencapsulation and in simulated in vivo drug release conditions. In vitro drug release studies carried out in simulated in vivo conditions in respect to pH, enzymatic and salt content confirmed the potential of the particles to release the drug in a controlled manner. The diffusional exponents according to the general exponential release equation indicated anomalous (non-Fickian) transport in 5-ASA release controlled by a polymer relaxation, erosion and degradation. Biodistribution studies of [(131)I]-5-ASA loaded chitosan-Ca-alginate microparticles, carried out within 2 days after peroral administration to Wistar male rats in which TNBS colitis was induced, confirmed the dominant localization of 5-ASA in the colon with low systemic bioavailability. Topics: Alginates; Animals; Anti-Inflammatory Agents, Non-Steroidal; B-Lymphocytes; Body Weight; Calcium; Calorimetry, Differential Scanning; Chemical Phenomena; Chemistry, Physical; Chitosan; Colitis; Colon; Crystallography, X-Ray; Delayed-Action Preparations; Drug Compounding; Drug Delivery Systems; Electrochemistry; Excipients; Gels; Magnetic Resonance Spectroscopy; Male; Mesalamine; Microspheres; Organ Size; Particle Size; Peroxidase; Rats; Rats, Wistar; Solubility; Spectroscopy, Fourier Transform Infrared; Tissue Distribution | 2007 |
A potential role for the vanilloid receptor TRPV1 in the therapeutic effect of curcumin in dinitrobenzene sulphonic acid-induced colitis in mice.
A protective role of the transient potential vanilloid receptor 1 (TRPV1) in intestinal inflammation induced by dinitrobenzene sulphonic acid (DNBS) has been recently demonstrated. Curcumin, the major active component of turmeric, is also able to prevent and ameliorate the severity of the damage in DNBS-induced colitis. We evaluated the possibility that curcumin (45 mg kg(-1) day p.o. for 2 days before and 5 days after the induction of colitis) was able to reduce DNBS-induced colitis in mice, by acting as a TRPV1 agonist. Macroscopic damage score, histological damage score and colonic myeloperoxidase (MPO) activity were significantly lower (by 71%, 65% and 73%, respectively; P < 0.01), in animals treated with curcumin compared with untreated animals. Capsazepine (30 mg kg(-1), i.p.), a TRPV1 receptor antagonist, completely abolished the protective effects of curcumin. To extend these data in vitro, Xenopus oocytes expressing rat TRPV1 were examined. Capsaicin-evoked currents (3.3 micromol L(-1)) disappeared subsequent either to removal of the agonist or subsequent to the addition of capsazepine. However, curcumin (30 micromol L(-1)) was ineffective both as regard direct modification of cell membrane currents and as regard interference with capsaicin-mediated effects. As sensitization of the TRPV1 receptor by mediators of inflammation in damaged tissues has been shown previously, our results suggest that in inflamed, but not in normal tissue, curcumin can interact with the TRPV1 receptor to mediate its protective action in DNBS-induced colitis. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzenesulfonates; Capsaicin; Cell Membrane; Colitis; Curcumin; Male; Membrane Potentials; Mice; Mice, Inbred BALB C; Oocytes; Peroxidase; Severity of Illness Index; TRPV Cation Channels; Xenopus | 2007 |
Anti-inflammatory properties of Lactobacillus gasseri expressing manganese superoxide dismutase using the interleukin 10-deficient mouse model of colitis.
Emerging evidence has implicated reactive oxygen species (ROS) in the pathogenesis of inflammatory bowel disease (IBD). Although intestinal epithelial cells produce the ROS-neutralizing enzyme superoxide dismutase (SOD), the protein and activity levels of copper/zinc (Cu/Zn) and manganese (Mn) SOD are perturbed in inflamed tissues of IBD patients. Thus we investigated the ability of MnSOD from Streptococcus thermophilus to reduce colitis symptoms in interleukin (IL) 10-deficient mice using Lactobacillus gasseri as a delivery vehicle. Cohorts of 13-15 IL-10-deficient mice were left untreated or supplemented with native L. gasseri or L. gasseri expressing MnSOD for 4 wk. Colonic tissue was collected and inflammation was histologically scored. The presence of innate immune cells was investigated by immunohistochemistry and the host antioxidant response was determined by quantitative PCR. It was demonstrated that L. gasseri was stably maintained in mice for at least 3 days. L. gasseri producing MnSOD significantly reduced inflammation in IL-10-deficient mice compared with untreated controls (P < 0.05), whereas the anti-inflammatory effects of both native and MnSOD producing L. gasseri were more pronounced in males. The anti-inflammatory effects of L. gasseri were associated with a reduction in the infiltration of neutrophils and macrophages. Transcripts of antioxidant genes were equivalent in colonic tissues obtained from control and probiotic-treated IL-10-deficient mice. This study demonstrates that L. gasseri producing MnSOD has significant anti-inflammatory activity that reduces the severity of colitis in the IL-10-deficient mouse. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Cyclooxygenase 2; Disease Models, Animal; Immunohistochemistry; Interleukin-10; Lactobacillus; Mice; Peroxidase; Probiotics; Specific Pathogen-Free Organisms; Superoxide Dismutase | 2007 |
Chemical characterization and anti-inflammatory effect of rauvolfian, a pectic polysaccharide of Rauvolfia callus.
The pectic polysaccharide named rauvolfian RS was obtained from the dried callus of Rauvolfia serpentina L. by extraction with 0.7% aqueous ammonium oxalate. Crude rauvolfian RS was purified using membrane ultrafiltration to yield the purified rauvolfian RSP in addition to glucan as admixture from the callus, with molecular weights 300 and 100-300 kD, respectively. A peroral pretreatment of mice with the crude and purified samples of rauvolfian (RS and RSP) was found to decrease colonic macroscopic scores, the total area of damage, and tissue myeloperoxidase activity in colons as compared with a colitis group. RS and RSP were shown to stimulate production of mucus by colons of the colitis mice. RSP appeared to be an active constituent of the parent RS. The glucan failed to possess anti-inflammatory activity. Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Male; Mice; Pectins; Peroxidase; Prednisolone; Rauwolfia | 2007 |
5-amino salicylic acid bound nanoparticles for the therapy of inflammatory bowel disease.
Nanoparticles (NP) are known for their specific accumulation in the inflamed tissues in the colon and may therefore allow a selective delivery to the site of inflammation including a reduction of adverse effects. 5-amino salicylic acid (5ASA) loaded NP were designed in order to investigate their therapeutic potential in the treatment of inflammatory bowel disease. 5ASA was covalently bound to poly(caprolactone) prior to all formulation steps. Oil/water emulsification or nanoprecipitation methods were used for the NP formulation. Particle diameters were either 200 or 350 nm for emulsification or nanoprecipitation, respectively. In-vitro drug release demonstrated a significant drug retention inside the NP formulation. Toxicity of the different formulations was evaluated on Caco-2 and HEK cell culture which was slightly increased for 5ASA grafted NP in comparison to blank NP (Me5ASA-NP: 75 microg/l; blank NP: 210 microg/l). In-vivo, clinical activity score and myeloperoxidase activity decreased after administration of all 5ASA containing formulations (untreated control: 28.0+/-5.6 U/mg; 5ASA-NP (0.5 mg/kg): 15.2+/-5.6 U/mg; 5ASA solution (30 mg/kg): 16.2+/-3.6 U/mg). NP formulations allowed to lower significantly the dose of 5ASA. These oral NP formulations demonstrated their therapeutic potential and appear to be an interesting approach for the therapy of inflammatory bowel disease. Topics: Aminosalicylic Acids; Animals; Anti-Inflammatory Agents; Caco-2 Cells; Cell Survival; Chemistry, Pharmaceutical; Colitis; Colon; Delayed-Action Preparations; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Carriers; Drug Compounding; Feasibility Studies; Gastrointestinal Agents; Humans; Male; Mice; Mice, Inbred C57BL; Nanoparticles; Particle Size; Peroxidase; Polyesters; Solubility; Technology, Pharmaceutical; Time Factors; Trinitrobenzenesulfonic Acid | 2007 |
Alpha-lipoic acid modulates gut inflammation induced by trinitrobenzene sulfonic acid in rats.
Alpha-lipoic acid (ALA) has been shown to combat oxidative stress by quenching a variety of reactive oxygen species. It is involved in the regeneration of exogenous and endogenous antioxidants, chelation of metal ions, and repair of oxidized proteins. This study aimed to evaluate the potential beneficial effect of ALA on trinitrobenzenesulfonic acid (TNBS)-induced gut ileitis and colitis in rats.. After 48 h of fasting, Sprague-Dawley rats underwent a laparotomy under ether anesthesia. TNBS solution 30 mg/mL in 40% ethanol (1 mL) was injected into the lumen, 10 cm proximal to the ileocolonic junction to induce ileitis or intrarectally 8 cm proximal to the anal sphincter to induce colitis. ALA (25 mg/kg intraperitoneally, twice a day) was given after induction of inflammation and continued for 3 days. All animals were decapitated 3 days after induction of the inflammation. The mucosal lesions of the ileum and colon were scored macroscopically and microscopically. Samples were taken for the measurement of malondialdehyde (MDA) and glutathione (GSH) levels, tissue-associated myeloperoxidase (MPO) activity and luminol- or lucigenin-enhanced chemiluminescence (CL).. Macroscopic scores, morphological changes and increased tissue lipid peroxidation with a concomitant reduction in GSH of the ileitis or colitis groups were all reversed by treatment with ALA. ALA treatment was also effective in improving tissue MPO activity and CL values, which were elevated in untreated ileitis or colitis groups.. ALA is beneficial in TNBS-induced gut inflammation in rats via suppression of neutrophil accumulation, preservation of endogenous glutathione and inhibition of reactive oxidant generation. Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Colon; Disease Models, Animal; Gastrointestinal Agents; Glutathione; Ileitis; Ileum; Lipid Peroxidation; Malondialdehyde; Neutrophil Infiltration; Neutrophils; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Thioctic Acid; Trinitrobenzenesulfonic Acid | 2007 |
Influence of simultaneous inhibition of cyclooxygenase-2 and inducible nitric oxide synthase in experimental colitis in rats.
The inflamed mucosa in ulcerative colitis produces high amount of prostaglandin (PG) and nitric oxide (NO) through inducible enzymes: cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), respectively, implicating them as potential anti-inflammatory drug targets. COX-2 or iNOS-related treatments in different models of colitis have yielded ambiguous results ranging from exacerbation of disease to abolition of inflammation. iNOS and COX-2 induction is blocked by potent anti-inflammatory glucocorticoids, however, serious side effects including relapses limit their usefulness in colitis for long time. Simultaneous inhibition of iNOS and COX-2 was investigated in the current study in 2, 4, 6 trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. Treatment group received rofecoxib, aminoguanidine hydrochloride or their combination at different doses at 48, 36, 24, 12 and 1 h prior to induction of colitis and 12 h later. Colonic myeloperoxidase (MPO), COX-2, nitrate and nitrite, tumor necrosis factor-alpha (TNF-alpha) and lipid peroxidation were maximally reduced by combination of 10 mg/kg rofecoxib and 30 mg/kg of aminoguanidine hydrochloride in TNBS-induced colitis in rats. However, maximum increase in SOD and catalase was noted by this combination. Rats treated with rofecoxib, aminoguanidine hydrochloride and their combinations reduced the inflammation, acute colonic damage produced by TNBS as verified by macroscopic changes in colon. Combination of rofecoxib (10 mg/kg) and aminoguanidine hydrochloride (30 mg/kg) has maximal protective effect on colonic injury induced by TNBS enema which is probably, via mechanism of local inhibition of iNOS and COX-2 activity in colonic mucosa and support the idea that simultaneous inhibition of iNOS and COX-2 inhibitors have a promising potential in the treatment of colitis. Topics: Animals; Catalase; Colitis; Colon; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Drug Therapy, Combination; Enzyme Inhibitors; Guanidines; Intestine, Large; Lactones; Lipid Peroxidation; Male; Nitrates; Nitric Oxide Synthase Type II; Nitrites; Peroxidase; Rats; Rats, Inbred Strains; Sulfones; Superoxide Dismutase; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2007 |
The effect of the cholinergic anti-inflammatory pathway on experimental colitis.
Inflammatory bowel diseases (IBD) are characterized by proinflammatory cytokines, tissue damage and loss of neuron in inflamed mucosa, which implies the cholinergic anti-inflammatory pathway may be destroyed during the process of inflammatory response. In the study, we identified the effect of cholinergic agonist as anabaseine (AN) and nicotinic receptor antagonist as chlorisondamine diiodide (CHD) on trinitrobenzene sulfonic acid (TNBS)-induced colitis, to investigate the potential therapeutic effect of the cholinergic anti-inflammatory pathway on IBD. Experimental colitis was induced by TNBS at day 1, 10 mug AN or 1.5 mug CHD was injected i.p. to mouse right after the induction of colitis, and repeated on interval day till the mice were sacrificed at day 8. Colonic inflammation was examined by histological analysis, myeloperoxidase (MPO) activity, and the production of tumour necrosis factor (TNF)-alpha in tissue. Lamina propria mononuclear cells (LPMC) were isolated, and NF-kappaB activation was detected by western blot. The mice with colitis treated by AN showed less tissue damage, less MPO activity, less TNF-alpha production in colon, and inhibited NF-kappaB activation in LPMC, compared with those mice with colitis untreated, whereas the mice with colitis treated by CHD showed the worst tissue damage, the highest MPO activity, the highest TNF-alpha level, and enlarged NF-kappaB activation in LPMC. Agonist of the cholinergic anti-inflammatory pathway inhibits colonic inflammatory response by downregulating the production of TNF-alpha, and inhibiting NF-kappaB activation, which suggests that modulating the cholinergic anti-inflammatory pathway may be a new potential management for IBD. Topics: Anabasine; Animals; Blotting, Western; Chlorisondamine; Cholinergic Agonists; Colitis; Disease Models, Animal; Inflammation; Male; Mice; NF-kappa B; Nicotinic Antagonists; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2007 |
Experimental endometriosis in the rat is correlated with colonic motor function alterations but not with bacterial load.
Endometriosis commonly presents with symptoms that mimic chronic gastrointestinal disorders. The authors used the autotransplantion model of endometriosis in rats to investigate the possible underlying mechanisms. After the rats were killed, the presence of endometriotic vesicles, colonic inflammation, and white blood cell (WBC) numbers in the peritoneal fluid was determined. Sections of colon and of jejunum were collected for measurement of myeloperoxidase (MPO) activity and bacterial counts, and isometric recording in response to acetylcholine was measured in segments of longitudinal and circular smooth muscle. Experimental animals had significantly more colonic damage, MPO activity, and WBC numbers than controls did. There was no significant difference in the total bacterial load; however, experimental animals demonstrated an increased tension in the longitudinal muscle, which correlated with WBC numbers and colonic damage. In summary, this study presents evidence for a significant effect of peritoneal endometriosis on colonic function and integrity, which may help explain the gastrointestinal symptoms associated with this disease. Topics: Animals; Colitis; Colony Count, Microbial; Disease Models, Animal; Endometritis; Female; Gastrointestinal Motility; In Vitro Techniques; Lactobacillus; Muscle Contraction; Peroxidase; Rats; Rats, Sprague-Dawley | 2007 |
Imaging biomarkers of inflammation in situ with functionalized quantum dots in the dextran sodium sulfate (DSS) model of mouse colitis.
Myeloperoxidase (MPO) and proinflammatory cytokines play an important role in the development of inflammation. These markers are generally measured using tedious ELISA procedures. In this study, a novel technique utilizing antibody conjugated quantum dot nanoparticles was developed to detect Myeloperoxidase, Interleukin-1alpha (IL-1alpha) and Tumor Necrosis Factor-alpha (TNF-alpha) in vivo in the dextran sodium sulfate (DSS) model of experimental colitis.. Colitis was induced in animals (n = 8 animals/group) by feeding 4% DSS solution ad libitum for seven to eight days. Quantum Dots (QDs) exhibiting fluorescence at various wavelengths were conjugated to MPO, IL-1alpha and TNF-alpha polyclonal antibodies and tested in vivo at various stages of colitis. Tissue sections obtained were imaged with confocal microscope. The image intensity obtained from the tissue specimen was correlated with clinical activity measured as Disease Activity Index (DAI).. Myeloperoxidase, IL-1alpha and TNF-alpha were visualized with quantum dots on various days of disease. The intensity of quantum dots increased with the increase in inflammation. The increase in intensity showed an excellent correlation with the DAI based on the clinical parameters.. The study demonstrated that multiple biomarkers can be detected simultaneously and their quantitative expression correlated well with clinical disease severity. This novel technology should facilitate design of a novel optical platform for imaging various biomarkers of inflammation, early detection of acute and chronic disease markers and inflammation-mediated cancer markers. This detection may also facilitate determination of therapeutic success. Topics: Animals; Biomarkers; Colitis; Dextran Sulfate; Female; Inflammation; Interleukin-1alpha; Mice; Peroxidase; Quantum Dots; Tumor Necrosis Factor-alpha | 2007 |
Lactobacillus fermentum, a probiotic capable to release glutathione, prevents colonic inflammation in the TNBS model of rat colitis.
Inflammatory bowel disease is associated with intestinal oxidative stress. In the present study we test the preventative effect of Lactobacillus fermentum, a probiotic that produces per se glutathione, in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis.. Colitis was induced in rats by intracolonic administration of 10 mg of TNBS dissolved in 0.25 ml of 50% ethanol. L. fermentum was administered orally (5x10(8) CFU suspended in 0.5 ml of skim milk) to a group of rats for 3 weeks, starting 2 weeks before colitis induction. Colonic damage was evaluated both histologically and biochemically, and the colonic luminal contents were used for bacterial studies as well as for short chain fatty acid (SCFA) production.. L. fermentum treatment resulted in an amelioration of the inflammatory response in colitic rats as evidenced histologically and by a significant reduction of colonic MPO activity (P<0.05). The probiotic partially counteracted the colonic glutathione depletion induced by the inflammatory process. In addition, probiotic-treated colitic rats showed significant lower colonic tumour necrosis factor (TNF)alpha levels (P<0.01) and inducible nitric oxide synthase (iNOS) expression when compared to non-treated rats. Finally, the probiotic induced growth of Lactobacilli species and production of SCFA in colonic contents in comparison with control colitic rats.. Administration of the probiotic L. fermentum facilitates the recovery of the inflamed tissue in the TNBS model of rat colitis, an effect associated with increased levels of glutathione as well as with amelioration of the production of some of the mediators involved in the inflammatory response of the intestine, such as TNFalpha and NO. Topics: Analysis of Variance; Animals; Colitis; Colony Count, Microbial; Disease Models, Animal; Fatty Acids, Volatile; Female; Glutathione; Inflammation Mediators; Intestinal Mucosa; Leukotriene B4; Limosilactobacillus fermentum; Neutrophil Infiltration; Nitric Oxide Synthase Type II; Oxidative Stress; Peroxidase; Probiotics; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Exacerbation of dextran sulfate sodium-induced colitis by dietary iron supplementation: role of NF-kappaB.
In colitis, iron therapy may be given to treat anemia, but it may also be detrimental based on our previous studies using a rat model with colitis where iron supplementation increased disease activity and oxidative stress. This effect was partially reduced by an antioxidant.. The aim of this study was to further evaluate, in rats with dextran sulfate sodium (DSS)-induced colitis, the effect of iron on neutrophilic infiltration, cytokines and nuclear factor kappa-B (NF-kappaB)-associated inflammation and to determine whether the addition of vitamin E would be beneficial.. Colitis was induced with DSS at 50 g/l in drinking water for 7 days. DSS rats were randomized to the following: DSS, receiving a control, non-purified diet (iron, 270 mg and DL-alpha-tocopherol acetate, 49 mg/kg); DSS+iron (diet+iron, 3,000 mg/kg); DSS+vitamin E (diet+DL-alpha-tocopherol acetate, 2,000 mg/kg); or the DSS+iron+vitamin E. Colonic inflammation, myeloperoxidase activity (MPO), lipid peroxides (LPO), proinflammatory cytokines [tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-6] and NF-kappaB binding activity were measured.. The DSS+iron group showed a significant increase in inflammatory scores, MPO, TNF-alpha, IL-1, LPO and NF-kappaB activity compared to DSS or DSS+vitamin E. The addition of vitamin E to iron (DSS+iron+vitamin E group) significantly reduced the inflammatory scores, TNF-alpha and IL-6. None of the other parameters were affected.. Iron increases disease activity in colitis, and this is associated with oxidative stress, neutrophilic infiltration, increased cytokines and activation of NF-kappaB. This detrimental effect was partially reduced by vitamin E. Topics: Animals; Antioxidants; Colitis; Cytokines; Dextran Sulfate; Dietary Supplements; Disease Models, Animal; Indicators and Reagents; Iron; Lipid Peroxides; Male; Neutrophils; NF-kappa B; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Wistar; Trace Elements; Vitamin E | 2006 |
Partially hydrolyzed guar gum down-regulates colonic inflammatory response in dextran sulfate sodium-induced colitis in mice.
Partially hydrolyzed guar gum (PHGG), a water-soluble dietary fiber produced by a controlled partial enzymatic hydrolysis of guar gum beans, has various physiological actions. The aim of the present study was to elucidate the beneficial effects of PHGG on colonic mucosal damage and on the inflammatory response in a dextran sulfate sodium (DSS) colitis model. After 2 weeks of prefeeding of PHGG, acute colitis was induced with 8% DSS in female BALB/c mice. Colonic mucosal inflammation was evaluated clinically, biochemically and histologically. Mucosal protein contents and mRNA levels of tumor necrosis factor-alpha (TNF-alpha) were determined by immunoassay and reverse transcription polymerase chain reaction. Disease activity scores determined by weight loss, stool consistency and blood in stool in DSS-treated mice were significantly lower in the PHGG-treated mice compared with the control mice. Shortening of the colon was significantly reversed by PHGG. Histological study also showed a reduced infiltration of inflammatory cells, especially neutrophils, and mucosal cell disruption in PHGG-treated mice compared with the control mice. The increases in tissue-associated myeloperoxidase activity and thiobarbituric acid-reactive substances after DSS administration were both significantly inhibited by pretreatment with PHGG. Partially hydrolyzed guar gum also inhibited increases in intestinal TNF-alpha protein and mRNA expression after DSS administration, respectively. These results suggest that chronic ingestion of PHGG prevents the development of DSS-induced colitis in mice via the inhibition of mucosal inflammatory response. Topics: Animals; Colitis; Colon; Colony Count, Microbial; Dextran Sulfate; Feces; Female; Galactans; Hydrolysis; Intestinal Mucosa; Mannans; Mice; Mice, Inbred BALB C; Neutrophils; Peroxidase; Plant Gums; RNA, Messenger; Thiobarbituric Acid Reactive Substances; Tumor Necrosis Factor-alpha | 2006 |
Selective inhibition of phosphodiesterase-4 ameliorates chronic colitis and prevents intestinal fibrosis.
The phosphodiesterase-4 (PDE4) inhibitors may be an important target in the treatment of several inflammatory conditions. The anti-inflammatory effect of PDE4 inhibitors bears similarities with that of steroids, without interfering with the hypophysary-adrenal-axis. We compared the effect of rolipram, a selective PDE4 inhibitor, with steroids on the clinical course of experimental colitis induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS). Three groups of rats (n = 20) received TNBS. One group received methylprednisolone from day 7, another group received rolipram from the same day, and control group received no further treatment. On days 14 and 21 after TNBS instillation, sets of 10 rats underwent colonic dialysis to measure eicosanoid release. Colonic lesions were blindly scored, and colons were homogenized for quantification of myeloperoxidase (MPO) activity and collagen content. Concentration of tumor necrosis factor alpha (TNF-alpha) and transforming growth factor beta1 (TGF-beta1) in colonic tissue was also measured. Both treatments reduced significantly the eicosanoid release and MPO activity. On day 14, both rolipram and methylprednisolone significantly reduced TNF-alpha content, but TGF-beta1 was only inhibited by rolipram. On day 21, lesion scores and collagen content were significantly reduced only in rolipram-treated group. In conclusion, PDE4 inhibition by rolipram markedly ameliorates the course of chronic colitis and it is superior to methylprednisolone in preventing late collagen deposition. Topics: 3',5'-Cyclic-AMP Phosphodiesterases; Animals; Chronic Disease; Colitis; Colon; Cyclic Nucleotide Phosphodiesterases, Type 4; Disease Models, Animal; Fibrosis; Male; Methylprednisolone; Peroxidase; Phosphodiesterase Inhibitors; Rats; Rats, Sprague-Dawley; Rolipram; Transforming Growth Factor beta; Transforming Growth Factor beta1; Tumor Necrosis Factor-alpha | 2006 |
Acutely administered melatonin is beneficial while chronic melatonin treatment aggravates the evolution of TNBS-induced colitis.
The aim of this study was to evaluate the effects of melatonin on the inflammatory response and hydroxyproline production in an experimental acute and chronic model of trinitrobenzene sulfonic (TNBS) acid-induced colitis in Wistar rats. In the acute model, melatonin (0.5, 1, and 2 mg/kg, i.p.) was applied 48, 24, and 1 hr prior to the induction of colitis and 24 and 48 hr after; the severity of colitis was less evident in melatonin-treated animals with significant response in the group treated with 2 mg/kg. All doses investigated significantly reduced the myeloperoxidase activity (MPO). In the chronic studies, melatonin (1 and 2 mg/kg, i.p.) was administered daily 24 hr before hapten instillation and for 7 or 21 days after TNBS; melatonin (2 mg/kg) worsened colitis evolution in the 21-day study with a significant increase in MPO activity and tumor necrosis factor-alpha production with respect to TNBS group. Histological slides were in concordance with macroscopic data where areas of extensive necrosis and edema, fibrosis, and absence of regenerated epithelium were observed. Moreover, the hydroxyproline determination, used as indicator of collagen production and fibrosis, also showed a marker increase. The results obtained in this experimental model showed that short-term administration is protective while in the long term it negatively influences evolution of inflammatory colitis; therefore, the immunostimulatory effect of melatonin in some situations when given chronically, such as during inflammatory bowel disease, might lead to negative consequences. Topics: Animals; Colitis; Colon; Disease Models, Animal; Drug Administration Schedule; Intestinal Mucosa; Male; Melatonin; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Reduction of experimental colitis in the rat by inhibitors of glycogen synthase kinase-3beta.
The effects of the inhibitors of glycogen synthase kinase-3beta (GSK-3beta), TDZD-8 and SB 415286, which can substantially reduce the systemic inflammation associated with endotoxic shock in vivo, have now been investigated on the acute colitis provoked by trinitrobenzene sulphonic acid (TNBS) in the rat. Administration of the GSK-3beta inhibitor TDZD-8 (0.1, 0.33 or 1.0 mg kg-1, s.c., b.i.d., for 3 days) caused a dose-dependent reduction in the colonic inflammation induced by intracolonic TNBS assessed after 3 days, both as the area of macroscopic involvement and as a score using 0-10 scale. Likewise, following administration of the GSK-3beta inhibitor SB 415286 (0.1, 0.33 or 1.0 mg kg-1, s.c., b.i.d., for 3 days), the extent and degree of the TNBS-provoked colonic inflammation was reduced. Administration of either TDZD-8 or SB 415286 reduced the fall in body weight following challenge with TNBS at each dose level studied. The increase in myeloperoxidase activity, an index of neutrophil infiltration into the TNBS-induced inflamed colon, was significantly inhibited by both TDZD-8 and SB 415286 at each dose level. The increase in the levels of the proinflammatory cytokine, TNF-alpha, in the inflamed colon was also significantly inhibited by either compound at the highest doses evaluated. The elevated levels of the transcription factor NF-kappaB subunit p65, as determined by Western blot in the nuclear extracts from the TNBS-provoked inflamed colonic tissue, were dose-dependently reduced by TDZD-8 or SB 415286 treatment. These findings demonstrate that two chemically distinct selective inhibitors of the activity of GSK-3beta reduce the inflammation and tissue injury in a rat model of acute colitis. The mechanisms underlying this anti-inflammatory action may be related to downregulation of NF-kappaB activity, involved in the generation of proinflammatory mediators. Topics: Aminophenols; Animals; Body Weight; Colitis; Colon; Dose-Response Relationship, Drug; Enzyme Inhibitors; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Male; Maleimides; Organ Size; Peroxidase; Rats; Rats, Wistar; Thiadiazoles; Transcription Factor RelA; Tumor Necrosis Factor-alpha | 2006 |
Matrine improves 2,4,6-trinitrobenzene sulfonic acid-induced colitis in mice.
Matrine is an alkaloid found in kinds of Sophora plants mainly including Sophora flavescens, Sophora alopecuroides and Sophora subprotrata. The aim of the present study was to evaluate therapeutic effects of matrine on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Two hours following colonic instillation of TNBS, matrine with several doses was given by gastric gavage once daily for 7 days. Comparing with the 0.9% NaCl-treated mice with TNBS-induced colitis, matrine (10 and 20 mg kg(-1))-treated mice with TNBS-induced colitis were shown improvements of weight loss, macroscopic score, histological score, and myeloperoxidase (MPO) activity. Moreover, treatments with matrine (10 and 20 mg kg(-1)) decreased the up-regulated mRNA and protein levels of tumour necrosis factor-alpha (TNF-alpha) caused by TNBS. Our findings suggest that matrine improves TNBS-induced colitis in mice and the therapeutic mechanism might be related to the reduction of up-regulated colonic TNF-alpha production caused by TNBS. Topics: Alkaloids; Animals; Anti-Inflammatory Agents; Body Weight; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Gene Expression Regulation; Matrines; Mice; Mice, Inbred BALB C; Neutrophils; Peroxidase; Quinolizines; RNA, Messenger; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Protection against dextran sodium sulfate-induced colitis by dehydroepiandrosterone and 7alpha-hydroxy-dehydroepiandrosterone in the rat.
In this study the anti-oxidant effect of DHEA and 7alpha-hydroxy-DHEA against oxidative stress induced by colitis was investigated in vivo in rats. The two steroids were intraperitoneally injected once daily (50 mg/kg body weight) for 7 days before the induction of colitis that was effected by a daily treatment of 5% (w/v) dextran sodium sulfate (DSS) in drinking water for 7 days. This was quantified by the evidence of weight loss, rectal bleeding, increased wall thickness, and colon length. The inflammatory response was assessed by neutrophil infiltration after a histological examination and myeloperoxidase (MPO) activity measurement. Two markers of oxidative damage were measured in colon homogenates after the onset of DSS treatment: protein carbonyls and thiobarbituric acid-reacting substances. The colonic metabolism of corticosterone by 11beta-hydroxysteroid dehydrogenases types 1 and 2 (11beta-HSD) was investigated in control and treated animals. Results indicated that colitis caused a decrease in body weight and colon length. Severe lesions were observed in the colon with a reduced number of goblet cells which contained less mucins. The lesions were associated with increased MPO activity and oxidative damage. Colonic inflammation down and up regulated the 11beta-HSD2 and 11beta-HSD1, respectively. Treatments by DHEA and 7alpha-hydroxy-DHEA attenuated the inflammatory response when MPO activity decreased; but this did not increase the colonic oxidation of corticosterone into 11-dehydrocorticosterone. Both DHEA and 7alpha-hydroxy-DHEA exerted a significant anti-oxidant effect against oxidative stress induced by colitis through reducing the oxidative damage to proteins and lipids. This resulted in a moderate increase in the amount of colonic mucus. Both DHEA and 7alpha-hydroxy-DHEA may prove useful in the prevention or treatment of colitis. Topics: 11-beta-Hydroxysteroid Dehydrogenase Type 1; 11-beta-Hydroxysteroid Dehydrogenase Type 2; Adjuvants, Immunologic; Animals; Antioxidants; Colitis; Dehydroepiandrosterone; Dextran Sulfate; Male; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Thiobarbituric Acid Reactive Substances; Weight Loss | 2006 |
Oligosaccharides isolated from goat milk reduce intestinal inflammation in a rat model of dextran sodium sulfate-induced colitis.
There is increased interest in the study of manipulation of the flora with pro- and prebiotics regarding inflammatory bowel disease. The aim of this work was to evaluate the effect of oligosaccharides from goat milk in a rat model of dextran sodium sulfate- (DSS-) induced colitis.. Twenty rats were fed the same diet but with different sources of fiber (5% of the diet): cellulose or a mixture of goat's milk oligosaccharides (GMO) and cellulose. DSS treatment was used to induce a colonic inflammation. Several clinical and inflammatory parameters, as well as intestinal micorbiota and gene expression by DNA microarray technology, were evaluated.. DSS induced a decrease in body weight which was not observed in rats fed the GMO (decrease of 21+/-11% in control rats vs increase of 5.2+/-8.6 in GMO rats, P<0.05). DSS also caused an acute colonic inflammatory process which was weaker in rats fed the GMO, as shown by colon myeloperoxidase activity (0.53+/-0.16 vs 0.14+/-0.07U/mg of protein, P<0.05), as well as clinical symptoms measured by a scoring system (1.25+/-1.14 vs 0.4+/-0.07, P<0.05). GMO rats also showed less severe colonic lesions and a more favorable intestinal microbiota. The expression of genes involved in intestinal function, such as mucine-3, was down-regulated in DSS-control rats but returned to normal values in GMO rats.. GMO reduce intestinal inflammation and contribute to the recovery of damaged colonic mucosa. Topics: Animals; Body Weight; Colitis; Colon; Dextran Sulfate; Diet; Fatty Acids, Volatile; Feces; Female; Gene Expression Profiling; Glutathione; Goats; Inflammation; Liver; Male; Milk; Oligonucleotide Array Sequence Analysis; Oligosaccharides; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley | 2006 |
Protective effect of geranylgeranylacetone on trinitrobenzene sulfonic acid-induced colitis in mice.
Geranylgeranylacetone (GGA) has recently been reported to have a protective effect against ischemic, injurious and apoptotic stress in several tissues. The aim of this study was to determine the effect of GGA on colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) in mice. Colitis was induced by intrarectal instillation of TNBS in 50% ethanol in BALB/c mice. Survival, change in body weight and change in wet colon weight were assessed. Histological score in the colon was evaluated 5 days after TNBS treatment. The level of myeloperoxidase (MPO) activity in the colon was also determined. Immunohistochemistry for CD4 in the colon was performed. In addition, the level of heat shock protein (HSP) 70 in the colon was determined by Western blot analysis. Mice were orally treated with GGA (300 mg/kg) 2 h before and every other day after starting TNBS administration. Treatment with GGA markedly improved the survival rate, and reduced the loss of body weight and loss of wet colon weight in mice with TNBS-induced colitis. GGA also suppressed the increase in MPO activity and the number of CD4-positive cells infiltrating the colons of mice with TNBS-induced colitis. Furthermore, treatment with GGA remarkably up-regulated the expression of HSP70 in the colons of mice with TNBS-induced colitis. Our results provide further evidence that GGA has therapeutic potential for intestinal inflammation. Topics: Animals; Body Weight; CD4-Positive T-Lymphocytes; Colitis; Diterpenes; HSP70 Heat-Shock Proteins; Male; Mice; Mice, Inbred BALB C; Organ Size; Peroxidase; Survival Rate; Trinitrobenzenesulfonic Acid | 2006 |
The free radical scavengers edaravone and tempol suppress experimental dextran sulfate sodium-induced colitis in mice.
Recent studies have suggested that the enhanced release of reactive oxygen species (ROS) plays an important role in the pathogenesis of clinical inflammatory bowel disease (IBD), such as ulcerative colitis and Crohn's disease. In the present study, we investigated the effects of the free radical scavengers edaravone and tempol in the development of experimental dextran sulfate sodium (DSS)-induced colitis in mice. Male BALB/cA mice were fed 4% (w/w of diet) DSS in standard powder chow for 8 days. Edaravone, tempol, or vehicle saline were then injected subcutaneously twice per day. After the experimental period, the colonic length, histological damage score, and mucosal myeloperoxidase (MPO) and serum interleukin-6 (IL-6) levels were measured. Edaravone (15 mg/kg/day) and tempol (5-15 mg/kg/day) suppressed the colonic shortening and the damage score. In particular, tempol at 15 mg/kg/day significantly attenuated the colonic shortening and damage score. Edaravone and tempol suppressed the serum IL-6 levels, and significantly suppressed the increased colonic MPO levels. These results strongly support the involvement of ROS in the pathogenesis of DSS-induced colitis. A clinical effect for edaravone and tempol in IBD patients is strongly expected. Topics: Animals; Antipyrine; Colitis; Cyclic N-Oxides; Dextran Sulfate; Disease Models, Animal; Edaravone; Free Radical Scavengers; Interleukin-6; Male; Mice; Mice, Inbred BALB C; Peroxidase; Spin Labels | 2006 |
Up-regulation of anandamide levels as an endogenous mechanism and a pharmacological strategy to limit colon inflammation.
Direct stimulation of cannabinoid CB1 receptors exerts a protective function in animal models of inflammatory bowel diseases (IBDs). However, it is not known whether endocannabinoids are up-regulated during IBDs in animals or humans, nor whether pharmacological elevation of endocannabinoid levels can be exploited therapeutically in these disorders. In this study we addressed these questions. Colon inflammation was induced in mice and rats with 2,4-dinitrobenzene- and 2,4,6-trinitrobenzene sulfonic acids (DNBS and TNBS), respectively. DNBS-treated mice were treated chronically (for 3 or 7 days) with inhibitors of anandamide enzymatic hydrolysis (N-arachidonoyl-serotonin, AA-5-HT) or reuptake (VDM11), 10 or 5 mg/kg, s.c., or with 5-amino-salicilic acid (5-ASA, 1.4 mg/kg, i.r.). Endocannabinoids (anandamide and 2-arachidonoylglycerol, 2-AG) were quantified in mouse colon, or in rat colon mucosa and submucosa, and in bioptic samples from the colon of patients with untreated ulcerative colitis, by liquid chromatography-mass spectrometry. A strong elevation of anandamide, but not 2-AG, levels was found in the colon of DNBS-treated mice, in the colon submucosa of TNBS-treated rats, and in the biopsies of patients with ulcerative colitis. VDM-11 significantly elevated anandamide levels in the colon of DNBS-treated mice and concomitantly abolished inflammation, whereas AA-5-HT did not affect endocannabinoid levels and was significantly less efficacious at attenuating colitis. 5-ASA also increased anandamide levels and abolished colitis. Thus, anandamide is elevated in the inflamed colon of patients with ulcerative colitis, as well as in animal models of IBDs, to control inflammation, and elevation of its levels with inhibitors of its cellular reuptake might be used in the treatment of IBDs. Topics: Adult; Aged; Amidohydrolases; Animals; Arachidonic Acids; Benzenesulfonates; Colitis; Colitis, Ulcerative; Colon; Disease Models, Animal; Drug Evaluation, Preclinical; Endocannabinoids; Female; Glycerides; Humans; Inflammatory Bowel Diseases; Intestinal Mucosa; Male; Mesalamine; Mice; Mice, Inbred C57BL; Middle Aged; Peroxidase; Polyunsaturated Alkamides; Rats; Rats, Wistar; Receptor, Cannabinoid, CB1; Serotonin; Specific Pathogen-Free Organisms; Trinitrobenzenesulfonic Acid | 2006 |
Long-term expression of corticotropin-releasing factor (CRF) in the paraventricular nucleus of the hypothalamus in response to an acute colonic inflammation.
This study examined the long-term effects of an acute colitis on central corticotropin-releasing factor (CRF) expression. An increase in CRF mRNA in the paraventricular nucleus of the hypothalamus (PVN) and the central nucleus of the amygdala (CeA) was observed during active colitis, and the effect in the PVN was maintained following recovery. In summary, hypothalamic gene expression of CRF persists in the PVN despite resolution of an acute colitis. Topics: Animals; Autoradiography; Colitis; Corticotropin-Releasing Hormone; Cytokines; Diagnostic Imaging; Electrophoretic Mobility Shift Assay; Gene Expression Regulation; Male; Paraventricular Hypothalamic Nucleus; Peroxidase; Rats; Rats, Sprague-Dawley; Time Factors; Trinitrobenzenesulfonic Acid | 2006 |
Effects of topical treatment of sodium butyrate and 5-aminosalicylic acid on expression of trefoil factor 3, interleukin 1beta, and nuclear factor kappaB in trinitrobenzene sulphonic acid induced colitis in rats.
Butyrate enemas have been shown to be effective in treatment of ulcerative colitis, but the mechanism of the effects of butyrate is not totally known. This study evaluates effects of topical treatment of sodium butyrate (NaB) and 5-aminosalicylic acid (5-ASA) on the expression of trefoil factor 3 (TFF3), interleukin 1beta (IL1beta), and nuclear factor kappaB (NFkappaB) in trinitrobenzene sulphonic acid (TNBS) induced colitis in rats.. Distal colitis was induced in male Wistar rats by colonic administration of TNBS and colonically treated with NaB, 5-ASA, combination of NaB and 5-ASA, and normal saline for 14 consecutive days. Colonic damage score, tissue myeloperoxidase (MPO) activity, TFF3 mRNA expression, serum IL1beta production, and tissue NFkappaB expression were determined, respectively.. Treatment of NaB, 5-ASA, and the combination improved diarrhoea, colonic damage score, and MPO activities, increased TFF3 mRNA expression, and decreased serum IL1beta production and tissue NFkappaB expression. The combination therapy of NaB and 5-ASA had better effects than any other single treatment.. The combination of topical treatment of NaB and 5-ASA was effective for relieving and repairing colonic inflammation and the effects were related to stimulation of TFF3 mRNA expression and down-regulation of IL1beta production and NFkappaB expression. Topics: Administration, Topical; Animals; Anti-Inflammatory Agents, Non-Steroidal; Butyrates; Colitis; Interleukin-1; Male; Mesalamine; Neuropeptides; NF-kappa B; Peroxidase; Rats; Rats, Wistar; RNA, Messenger; Sulfonic Acids; Trefoil Factor-3; Trinitrobenzenes | 2006 |
Noradrenergic and cholinergic neural pathways mediate stress-induced reactivation of colitis in the rat.
Evidence to date suggests that stress-induced exacerbation or relapse of intestinal inflammation in inflammatory bowel disease requires both activation of the autonomic nervous system and the activation of the immune system by the presence of previously encountered luminal antigens. The aim of the present study was to further explore these associations and to determine the role of the autonomic nervous in modulating the intestinal inflammatory response to stress. Rats healed from an initial dinitrobenzene sulfonic acid-induced colitis were given a non-colitic dose of dinitrobenzene sulfonic acid (dissolved in saline) or 0.9% saline intra-rectally and then subjected to restraint stress. Cardiac sympathovagal balance was assessed by power spectral analysis of heart rate variability data collected from telemetric electrocardiogram recordings before, during and post stress. Only rats that were stressed and received dinitrobenzene sulfonic acid showed an inflammatory relapse characterized by significant macroscopic damage and elevated myeloperoxidase activity associated with a significant infiltration of mucosal and submucosal T lymphocytes. No difference in inflammatory markers was observed in animals that received intra-rectal saline and restraint stress. Rats subjected to stress and intra-rectal dinitrobenzene sulfonic acid demonstrated an increase in sympathetic activity with a nearly four fold increase in LF:HF ratio during stress and a significant increase in heart rate. Shortly after cessation of stress, the LF:HF ratio decreased significantly, returning to baseline levels, however the heart rate remained significantly elevated over baseline levels following stress, but decreased to a level that was significantly lower than during stress. The stress/dinitrobenzene sulfonic acid-induced relapses were preventable by pre-treating rats with hexamethonium (a nicotinic cholinergic ganglion blocking agent) or the co-administration of atropine (a muscarinic cholinoceptor antagonist) and bretylium (a noradrenergic ganglion blocking agent), but was not prevented when either atropine or bretylium were administered alone. This study utilizes an established model of chemically induced colitis that when integrated with stress results in relapsing inflammatory bowel disease. Moreover, this study demonstrates that noradrenergic and cholinergic neural pathways mediate the stress response critical for the relapse of colitis. Topics: Acute Disease; Animals; Atropine; Autonomic Pathways; Bretylium Tosylate; CD3 Complex; Colitis; Colon; Hexamethonium; Immunohistochemistry; Nicotinic Antagonists; Parasympathetic Nervous System; Parasympatholytics; Peroxidase; Rats; Rats, Sprague-Dawley; Recurrence; Stress, Psychological; Sympathetic Nervous System; Sympatholytics; Vagus Nerve | 2006 |
Effect of a novel water-soluble vitamin E derivative as a cure for TNBS-induced colitis in rats.
Lipid peroxidation mediated by oxygen free radicals plays an important role in the pathogenesis of inflammatory bowel disease (IBD). Vitamin E is a lipid-soluble antioxidant and is generally considered to protect against lipid peroxidation of the cell membrane and to scavenge singlet oxygen and superoxide anion radical. Therefore, vitamin E or its derivatives are expected to have particular application for patients suffering from IBD. The aim of this study was to investigate the antioxidative effects of the water-soluble vitamin E derivative, 2-(alpha-D-glucopyranosyl)methyl-2,5,7,8-tetra-methylchroman-6-ol(TMG), on the therapy of experimental colitis in rats. Colitis was induced in male Wistar rats weighing 200 g using an enema of trinitrobenzene sulfonic acid (TNBS) dissolved in 50% ethanol; TMG dissolved in physiological saline was injected intra-peritoneally every day from 24 h after the enema of TNBS. The damage score, wet weight of the colon, and increase in body weight were estimated 1 week after the enema of TNBS. Thiobarbituric acid-reactive substances (TBA-RS), an index of lipid peroxidation, and tissue-associated myeloperoxidase (MPO) activity in the colonic mucosa were measured 1 week after the induction of colitis. As a result, increase in body weight was inhibited by the induction of colitis, although the inhibition was reduced in the group treated with TMG. The damage score, wet weight, TBA-RS and MPO activity were increased significantly in the colitis group; however, they were inhibited by the administration of TMG. These results suggest that TMG is effective for the treatment of colitis in rats induced by TNBS. In the future, TMG could be a new therapeutic agent for IBD. Topics: Animals; Body Weight; Chromans; Colitis; Colon; Cytokines; Glycosides; Inflammation; Intestinal Mucosa; Male; Peroxidase; Rats; Rats, Wistar; Solubility; Thiobarbituric Acid Reactive Substances; Trinitrobenzenesulfonic Acid; Vitamin E | 2006 |
The effects of resveratrol, a phytoalexin derived from red wines, on chronic inflammation induced in an experimentally induced colitis model.
Neutrophil infiltration, proinflammatory cytokines, eicosanoid generation and oxidative stress have been implicated in colitis. Resveratrol is a polyphenolic compound found in grapes and wine, with multiple pharmacological actions, including anti-inflammatory, antioxidant, antitumour and immunomodulatory activities. In a previous report, we documented that resveratrol decreases the degree of inflammation associated with acute experimental colonic inflammation, but its effects on chronic experimental colitis remain undetermined. The aim of this research was to investigate the effects of resveratrol on the chronic colonic injury caused by intracolonic instillation of trinitrobenzenesulphonic acid (TNBS) in rats. The inflammatory response was assessed by histology and myeloperoxidase activity. Tumour necrosis factor alpha (TNF-alpha) production, histological and histochemical analysis of the lesions were also carried out. We determined the production of prostaglandin (PG) E2 and D2 in colon mucosa, as well as cyclooxygenase (COX)-1 and -2 and nuclear transcription factor NF-kappa B (NF-kappaB) p65 protein expression. Finally, since resveratrol has been found to modulate apoptosis, we intended to elucidate its effects on colonic mucosa under chronic inflammatory conditions. Resveratrol (10 mg kg(-1) day(-1)) significantly attenuated the damage score and corrected the disturbances in morphology associated to injury. In addition, the degree of neutrophil infiltration and the levels of TNF-alpha were significantly ameliorated. Resveratrol did not modify PGD2 levels but returned the decreased PGE2 values to basal levels and also reduced COX-2 and the NF-kappaB p65 protein expression. Furthermore, treatment of rats with resveratrol caused a significant increase of TNBS-induced apoptosis in colonic cells. In conclusion, resveratrol reduces the damage in chronic experimentally induced colitis, alleviates the oxidative events, returns PGE2 production to basal levels and stimulates apoptosis in colonic cells. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Cyclooxygenase 1; Cyclooxygenase 2; Dinoprostone; Gene Expression Regulation; Inflammation; Male; Membrane Proteins; NF-kappa B; Peroxidase; Phytoalexins; Prostaglandin D2; Rats; Rats, Wistar; Resveratrol; Sesquiterpenes; Stilbenes; Terpenes; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Wine | 2006 |
Adoptive transfer of nontransgenic mesenteric lymph node cells induces colitis in athymic HLA-B27 transgenic nude rats.
HLA-B27 transgenic (TG) rats develop spontaneous colitis when colonized with intestinal bacteria, whereas athymic nude (rnu/rnu) HLA-B27 TG rats remain disease free. The present study was designed to determine whether or not HLA-B27 expression on T cells is required for development of colitis after transfer of mesenteric lymph node (MLN) cells into rnu/rnu HLA-B27 recipients. Athymic nontransgenic (non-TG) and HLA-B27 TG recipients received MLN cells from either TG or non-TG rnu/+ heterozygous donor rats that contain T cells. HLA-B27 TG rnu/rnu recipients receiving either non-TG or TG MLN cells developed severe colitis and had higher caecal MPO and IL-1beta levels, and their MLN cells produced more IFN-gamma and less IL-10 after in vitro stimulation with caecal bacterial lysate compared to rnu/rnu non-TG recipients that remained disease free after receiving either TG or non-TG cells. Interestingly, proliferating donor TG T cells were detectable one week after adoptive transfer into rnu/rnu TG recipients but not after transfer into non-TG recipients. T cells from either non-TG or TG donors induce colitis in rnu/rnu TG but not in non-TG rats, suggesting that activation of effector T cells by other cell types that express HLA-B27 is pivotal for the pathogenesis of colitis in this model. Topics: Adoptive Transfer; Animals; Animals, Genetically Modified; Bacteria; Cecum; Cell Extracts; Cell Proliferation; Colitis; Cytokines; Disease Models, Animal; HLA-B27 Antigen; Interleukin-1; Lymphocyte Activation; Lymphocyte Transfusion; Mesentery; Peroxidase; Rats; Rats, Inbred F344; Rats, Nude | 2006 |
Crucial role of the melanocortin receptor MC1R in experimental colitis.
alpha-Melanocyte stimulating hormone (alpha MSH) is known to exert anti-inflammatory effects, for example in murine DSS (dextran sodium sulphate induced) colitis. The anti-inflammatory functions of alpha MSH are mediated by the melanocortin1-receptor (MC1R) in an autoregulatory loop. The aim of this study was therefore to determine whether a breakdown of the alpha MSH-MC1R pathway leads to worsening of disease.. Experimental colitis was induced in mice with a frameshift mutation in the MC1R gene (MC1Re/e), C57BL/6 wild type mice, and MC1Re/e-C57BL/6 bone marrow chimeras. The course of inflammation was monitored by weight loss, histological changes in the colon, and myeloperoxidase activity. In addition, MC1R expression was analysed in intestinal epithelial cells.. While the colon of untreated MC1Re/e appeared normal, the course of DSS-colitis in MC1Re/e mice was dramatically aggravated, with a significantly higher weight loss and marked histological changes compared to C57BL/6WT. The inflammation eventually led to death in all MC1Re/e, while all C57BL/6WT survived. Similar observations were detected in a transmissible murine colitis model induced by Citrobacter rodentium. Infected MC1Re/e showed delayed clearance of infection. To determine whether missing haematopoietic cell expressed MC1R was responsible, DSS colitis was induced in MC1Re/e-C57BL/6 bone marrow chimeras. MC1Re/e mice receiving MC1R+ bone marrow showed a similar course of inflammation to non-transplanted MC1Re/e. Likewise, transplantation of MC1R bone marrow into C57BL/6WT mice did not lead to any worsening of disease.. This is the first study to show a functional role of MC1R in intestinal inflammation. The data suggest a pivotal role of non-haematopoietic cell expressed MC1R in the host's response to pathogenic stimuli. Topics: alpha-MSH; Animals; Bone Marrow Cells; Bone Marrow Transplantation; Chimera; Citrobacter; Colitis; Enterobacteriaceae Infections; Female; Immunoblotting; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Peroxidase; Receptor, Melanocortin, Type 1 | 2006 |
Plant originated glycoprotein has anti-oxidative and anti-inflammatory effects on dextran sulfate sodium-induced colitis in mouse.
We investigated the preventive effect of glycoprotein (27 kDa) isolated from Gardenia jasminoides Ellis (GJE) fruits on colitis in dextran sulfate sodium (DSS, 3%)-induced A/J mice which were administrated orally for 7 days. Anti-inflammatory activity of GJE glycoprotein was assessed by neutrophil infiltration and colonic lipid peroxidation, and determined by myeloperoxidase (MPO) activity and levels of thiobarbituric acid reactive substances (TBARS), respectively in DSS treatment system. The activities of antioxidative enzymes [catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)], activation of inflammation related mediators (iNOS, COX-2, and NF-kappaB), and production of nitric oxide (NO) and reactive oxygen species (ROS) were also measured. The results of this study showed that GJE glycoprotein (80 microg/ml) has a scavenging property to inhibit the intracellular ROS production in RAW 264.7 cells and that GJE glycoprotein (80 mg/kg BW) significantly suppressed the increase in the MPO activity, TBARS level, and NO production, inflammation related mediators [iNOS, COX-2, and NF-kappaB (p50)] activity in DSS-induced mice. Interestingly, the activities of CAT, SOD, and GPx were gradually augmented after a supplement of GJE glycoprotein. Therefore, we suggest that GJE glycoprotein is preventive and therapeutic agent for the ulcerative colitis. Topics: Analysis of Variance; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Blotting, Western; Catalase; Cells, Cultured; Colitis; Cyclooxygenase 2; Dextran Sulfate; Enzyme Activation; Gardenia; Glutathione Peroxidase; Glycoproteins; Lipid Peroxidation; Male; Mice; Neutrophil Infiltration; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Reactive Oxygen Species; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances | 2006 |
Antioxidant therapy with N-acetylcysteine plus mesalamine accelerates mucosal healing in a rodent model of colitis.
The aims of this study were to examine the ability of the antioxidant N-acetylcysteine (NAC) and mesalamine (5-ASA) alone and in combination to affect TNBS-induced colitis in rat. Three days following induction of TNBS colitis rats were randomized to receive daily intracolonic treatment with NAC, 5-ASA, and NAC plus 5-ASA for 5 or 8 days. At the end of the treatment period macroscopic and microscopic colonic injuries were scored. Myeloperoxidase (MPO) activity and cytokine gene expression were measured in colonic tissues. Results indicated that treatment with NAC plus 5-ASA caused a significantly greater reduction in colonic injury than either agent alone. Furthermore, combination therapy inhibited significantly MPO activity and inflammatory cytokine gene expression in the distal colon of TNBS-treated animals. The beneficial effects of NAC plus 5-ASA on reduction of colonic injury and promotion of healing were most evident after 8 days of treatment. Topics: Acetylcysteine; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Biopsy, Needle; Colitis; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Therapy, Combination; Immunohistochemistry; Inflammation Mediators; Male; Mesalamine; Peroxidase; Probability; Random Allocation; Rats; Rats, Sprague-Dawley; Reference Values; Sensitivity and Specificity | 2006 |
Alteration of nitrergic neuromuscular transmission as a result of acute experimental colitis in rat.
Nitric oxide (NO) is a non-adrenergic, non-cholinergic neurotransmitter found in the enteric nervous system that plays a role in a variety of enteropathies, including inflammatory bowel disease. Alteration of nitrergic neurons has been reported to be dependent on the manner by which inflammation is caused. However, this observed alteration has not been reported with acetic acid-induced colitis. Therefore, the purpose of the current study was to investigate changes in nitrergic neuromuscular transmission in experimental colitis in a rat model. Distal colitis was induced by intracolonic administration of 4 % acetic acid in the rat. Animals were sacrificed at 4 h and 48 h postacetic acid treatment. Myeloperoxidase activity was significantly increased in the acetic acid-treated groups. However, the response to 60 mM KCl was not significantly different in the three groups studied. The amplitude of phasic contractions was increased by Nomega-nitro-L-arginine methyl ester (L-NAME) in the normal control group, but not in the acetic acid-treated groups. Spontaneous contractions disappeared during electrical field stimulation (EFS) in normal group. However, for the colitis groups, these contractions initially disappeared, and then reappeared during EFS. Moreover, the observed disappearance was diminished by L-NAME; this suggests that these responses were NO-mediated. In addition, the number of NADPH-diaphorase positive nerve cell bodies, in the myenteric plexus, was not altered in the distal colon; whereas the area of NADPH-diaphorase positive fibers, in the circular muscle layer, was decreased in the acetic acidtreated groups. These results suggest that NO-mediated inhibitory neural input, to the circular muscle, was decreased in the acetic acid-treated groups. Topics: Acetic Acid; Animals; Colitis; Colon; Indicators and Reagents; Male; Muscle Contraction; Muscle, Smooth; Myenteric Plexus; NADPH Dehydrogenase; Neuromuscular Junction; NG-Nitroarginine Methyl Ester; Nitrergic Neurons; Nitric Oxide; Peroxidase; Potassium Chloride; Rats; Rats, Sprague-Dawley | 2006 |
Rosuvastatin, a new HMG-CoA reductase inhibitor, reduces the colonic inflammatory response in dextran sulfate sodium-induced colitis in mice.
The aim of the present study was to elucidate the beneficial effects of rosuvastatin, a new HMG-CoA reductase inhibitor, on colonic mucosal damage and on the inflammatory response in a dextran sulfate sodium (DSS) colitis model. Acute colitis was induced using 8% DSS in female BALB/c mice. Colonic mucosal inflammation was evaluated clinically, biochemically, and histologically. Mucosal protein contents and mRNA levels of tumor necrosis factor (TNF)-alpha were determined by immunoassay and real time-PCR. The mRNA levels of endothelial nitric oxide synthase (eNOS) were determined by real-time PCR. Disease activity scores in DSS-induced colitis model mice, as determined by weight loss, stool consistency, and blood in stool, were significantly lower in the rosuvastatin-treated mice than in control mice. Shortening of the colon was significantly reversed by rosuvastatin. Increases in tissue-associated myeloperoxidase activity and thiobarbituric acid-reactive substances after DSS administration were both significantly inhibited by treatment with rosuvastatin. Rosuvastatin also inhibited increases in intestinal TNF-alpha protein and mRNA expression after DSS administration, respectively. The mucosal mRNA levels of eNOS were decreased after DSS administration, but preserved in mice treated with rosuvastatin. These results suggest that rosuvastatin prevents the development of DSS-induced colitis in mice via the inhibition of mucosal inflammatory responses associated with the preservation of eNOS transcription. Topics: Animals; Colitis; Colon; Cyclic N-Oxides; Dextran Sulfate; Female; Fluorobenzenes; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Inflammatory Bowel Diseases; Mice; Mice, Inbred BALB C; Nitric Oxide Synthase Type III; Peroxidase; Pyrimidines; RNA, Messenger; Rosuvastatin Calcium; Sulfonamides; Thiobarbituric Acid Reactive Substances; Tumor Necrosis Factor-alpha | 2006 |
Intestinal anti-inflammatory activity of combined quercitrin and dietary olive oil supplemented with fish oil, rich in EPA and DHA (n-3) polyunsaturated fatty acids, in rats with DSS-induced colitis.
Previous studies have described the intestinal anti-inflammatory effects exerted by the bioflavonoid quercitrin (QR) and by an n-3 polyunsaturated fatty acids (PUFA)-enriched diet in experimental models of rat colitis. The aim of the present study was to test if the combination of both treatments would result in an improvement in the intestinal anti-inflammatory effect achieved separately.. Colitis was induced in female Wistar rats by incorporating dextran sodium sulfate (DSS) in drinking water at 5% (w/v) for 5 days and at 2% (w/v) for the following 10 days. Five groups of rats (n=10) were used: two of them received an olive-oil-based diet with fish oil, rich in n-3 PUFA (FO diet) for 2 weeks before colitis induction and until the end of the experiment, and one of those also was administered daily QR (1mg/kg, PO), starting when DSS concentration was changed. DSS colitis was induced in other two groups fed with standard rat diet, one of them being administered QR as before. A non-colitic group fed standard diet was also included. After that period, the rats were sacrificed and colonic damage was assessed both histologically and biochemically.. The concurrent administration of FO diet and QR exhibited an intestinal anti-inflammatory effect, as evidenced by a significant improvement of all biochemical parameters of colonic inflammation assayed in comparison with non-treated colitic rats. Thus, both colonic myeloperoxidase (MPO) and alkaline phosphatase (AP) activities were significantly reduced compared with untreated colitic rats. In addition, a complete restoration of colonic glutathione content, which was depleted as a consequence of the colonic insult, was obtained in rats treated with QR plus FO diet; this content was even higher than that obtained when colitic rats were treated with FO diet alone. When compared with the control colitic group, the combined treatment was also associated with a lower colonic nitric oxide synthase and cyclooxygenase-2 expression as well as with a significant reduction in different colonic proinflammatory mediators assayed, i.e. leukotriene B(4), tumor necrosis factor alpha and interleukin 1beta, showing a significantly greater inhibitory effect of the latter in comparison with rats receiving FO diet without the flavonoid.. These results support the potential synergism between the administration of the flavonoid and the incorporation of olive oil and n-3 PUFA to the diet for the treatment of these intestinal inflammatory disorders. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Colitis; Colon; Dextran Sulfate; Diet; Dietary Supplements; Docosahexaenoic Acids; Eicosapentaenoic Acid; Fatty Acids, Omega-3; Female; Fish Oils; Kinetics; Olive Oil; Peroxidase; Plant Oils; Quercetin; Rats; Rats, Wistar | 2006 |
[Effects of total base of Sophora alopecuroides on expression of SOD, MDA, NO, MPO in rats with experimental colitis].
To investigate the effects of total base of Sophora alopecuroides on expression of SOD, MDA, NO, MPO in rats with experimental colitis (UC).. SD rats were randomized into 6 groups and colitis was induced by administrating 2,4,6-trinitrobenzesulphonic acid (TNB) recatlly in rats. Rats were given drug by stomach after the first day for 3 weeks, and sacrificed at 23rd day to determine the content of MDA and activities of SOD, NO, MPO in colonic mucosa, and to estimate the symptom and colonic histology.. In UC rats, SOD was significantly decreased whereas MDA, NO, MPO were increased when compared with the normal group (P < 0.05). In all treatment groups, Sophora alopecuroides could increase SOD, decrease MDA, NO, MPO (P < 0.05), and improve the symptoms and histological damages.. The total dose of S. alopecuroides may ameliorates or alleviate the symptoms of UC through inhibiting oxygen free radical reaction, decreasing the generation of NO and exerting anti-inflammatory effects. Topics: Alkaloids; Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Female; Intestinal Mucosa; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Plants, Medicinal; Random Allocation; Rats; Rats, Sprague-Dawley; Sophora; Superoxide Dismutase | 2006 |
Critical role of MCP-1 in the pathogenesis of experimental colitis in the context of immune and enterochromaffin cells.
Mucosal changes in inflammatory bowel disease (IBD) are characterized by ulcerative lesions accompanied by a prominent infiltrate of inflammatory cells including lymphocytes, macrophages, and neutrophils and alterations in 5-hydroxytryptamine (5-HT)-producing enterochromaffin (EC) cells. Mechanisms involved in recruiting and activating these cells are thought to involve a complex interplay of inflammatory mediators. Studies in clinical and experimental IBD have shown the upregulation of various chemokines including monocyte chemoattractant protein (MCP)-1 in mucosal tissues. However, precise information on the roles of this chemokine or the mechanisms by which it takes part in the pathogenesis of IBD are not clear. In this study, we investigated the role of MCP-1 in the development of hapten-induced experimental colitis in mice deficient in MCP-1. Our results showed a significant reduction in the severity of colitis both macroscopically and histologically along with a decrease in mortality in MCP-1-deficient mice compared with wild-type control mice. This was correlated with a downregulation of myeloperoxidase activity, IL-1beta, IL-12p40, and IFN-gamma production, and infiltration of CD3+ T cells and macrophages in the colonic mucosa. In addition, we observed significantly lower numbers of 5-HT-expressing EC cells in the colon of MCP-1-deficient mice compared with those in wild-type mice after dinitrobenzenesulfonic acid. These results provide evidence for a critical role of MCP-1 in the development of colonic inflammation in this model in the context of immune and enteric endocrine cells. Topics: Animals; CD3 Complex; Chemokine CCL2; Colitis; Cytokines; Dinitrofluorobenzene; Enterochromaffin Cells; Immunity, Cellular; Immunohistochemistry; Interferon-gamma; Macrophages; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Serotonin; Spleen; T-Lymphocytes | 2006 |
Local treatment of experimental colitis in the rat by negatively charged liposomes of catalase, TMN and SOD.
Superoxide dismutase (SOD), 4-amino tempol (tempamine, denoted as TMN) and catalase were encapsulated into negatively charged liposomes. The activity of the antioxidants against dinitrobenzenesulfonic acid (DNBS) induced colitis was tested in the rat and compared to the anti-inflammatory activity of the native enzymes and free TMN. Inflammation severity was assessed by monitoring tissue myeloperoxidase (MPO) activity, thiobarbituric acid reactive species (TBARS) amounts and by comparing the weights of the dissected colons. In all cases, the liposomal preparations of the antioxidants were more effective than the free molecules in the treatment of the experimental colitis, probably due to the attachment of the negatively charged liposomes, and consequently a longer residence time and better uptake of the antioxidants to the inflamed mucosa. This study suggests that low and high molecular weight antioxidants delivered via anionic liposomes can serve as a novel targeted therapy to treat chronic inflammation of the colonic epithelium, such as ulcerative colitis. Topics: Animals; Colitis; Cyclic N-Oxides; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances | 2006 |
Colitis-induced oxidative damage of the colon and skeletal muscle is ameliorated by regular exercise in rats: the anxiolytic role of exercise.
Epidemiological studies have shown that exercise protects the gastrointestinal tract, reducing the risk of diverticulosis, gastrointestinal haemorrhage and inflammatory bowel disease, while many digestive complaints occurring during exercise are attributed to the adverse effects of exercise on the colon. In order to assess the effects of regular exercise on the pathogenesis of colitis, Sprague-Dawley rats of both sexes were either kept sedentary or given exercise on a running wheel (0.4 km h(-1), 30 min for 3 days week(-1)). At the end of 6 weeks, under anaesthesia, either saline or acetic acid (4%, 1 ml) was given intracolonically. Holeboard tests were performed for the evaluation of anxiety at 24 h before and 48 h after induction of colitis. Increased 'freezing time' in the colitis-induced sedentary group, representing increased anxiety, was reduced in the exercised colitis group (P < 0.05). On the third day following the colonic instillation, the rats were decapitated under brief ether anesthesia and the distal 8 cm of the colons were removed. In the sedentary colitis group, macroscopic and microscopic damage scores, malondialdehyde level and myeloperoxidase activity were increased when compared to the control group (P < 0.01-0.001), while exercise prior to colitis reduced all the measurements with respect to sedentary colitis group (P < 0.05-0.001). The results demonstrate that low-intensity, repetitive exercise protects against oxidative colonic injury, and that this appears to involve the anxiolytic effect of exercise, suggesting that exercise may have a therapeutic value in reducing stress-related exacerbation of colitis. Topics: Animals; Anxiety; Colitis; Colon; Female; Male; Malondialdehyde; Muscle, Skeletal; Oxidative Stress; Peroxidase; Physical Conditioning, Animal; Rats | 2006 |
Role of TNF-alpha in muscularis inflammation and motility disorder in a TNBS-induced colitis model: clues from TNF-alpha-deficient mice.
Macroscopic and histological analysis revealed that the colonic inflammation induced by 2,4,6-trinitrobenzenesulphonic acid (TNBS) was of lower grade in tumour necrosis factor-alpha (TNF-alpha)(-/-) mice than in wild-type mice. Myeloperoxidase activity, an indicator of neutrophilic infiltration, was also low in both the mucosal and smooth muscle layer of the TNF-alpha(-/-) mouse colon. After the induction of inflammation with TNBS, the levels of proinflammatory cytokines, such as TNF-alpha, interleukin-1beta and interleukin-6, were elevated both in the inflamed mucosa and muscle layers in the wild-type mice; however, the productions of these cytokines were greatly reduced in the TNF-alpha(-/-) mouse colon. The contractions of isolated colonic smooth muscle strips induced by several stimulatory agents were significantly decreased after treatment with TNBS in wild-type mice; however, these contractions were scarcely affected in TNF-alpha(-/-) mice. Finally, using the organ culture method, we found that TNF-alpha directly (independent of mucosal inflammation) disturbs the smooth muscle function. These results suggest that TNF-alpha plays an essential role not only in mucosal inflammation but also in muscularis inflammation in the colon of mice with TNBS-induced colitis, and that TNF-alpha directly induces motor dysfunctions by acting on the smooth muscle. Topics: Animals; Colitis; Disease Models, Animal; Gastrointestinal Motility; Inflammation; Interleukin-1; Interleukin-6; Intestinal Mucosa; Male; Mice; Mice, Inbred C57BL; Muscle Contraction; Muscle, Smooth; Peroxidase; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Effects of statins on experimental colitis in normocholesterolemic rats.
The results of previous studies suggest that statins have a direct anti-inflammatory effect that is not directly related to their cholesterol-lowering activity. The aim of this study was to investigate the effect of simvastatin (SIM) and fluvastatin (FLU) on trinitrobenzene sulfonic acid (TNBS)-induced colonic inflammation in rats.. The drugs were given for 3 days (0.1 and 1 mg/kg day-1; intraperitoneally) after induction of colitis. The lesions in the distal colon were scored at the macroscopic and microscopic level. Tissue malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were assessed and formation of reactive oxygen species and peroxynitrite was monitored by chemiluminescence (CL) assay. Trunk blood was collected for the measurement of serum tumor necrosis factor (TNF)-alpha level.. Treatment with SIM reduced the lesion score of the colitis group at macroscopic level (p<0.05), but there was no effect of treatment with FLU. The increase in colonic MDA level of the colitis group was reduced by both drugs at all doses (p<0.05-0.001). The decrease in GSH and the an increase in MPO activity in the colitis group were reversed by SIM at all doses (p<0.01), but FLU had no effect. An increase in colonic lucigenin CL value in the colitis group was reduced by SIM and FLU at all doses (p<0.001) and an increase in peroxynitrite ratio in the colitis group showed a significant reduction in SIM-treated groups; FLU reduced this effect at a dose of 1 mg/kg (p<0.01). An increase in tissue collagen content and serum TNF-alpha level in the colitis group was reversed by both drugs at all doses (p<0.001).. SIM and FLU seemed to be beneficial in a TNBS-induced rat colitis model through the prevention of lipid peroxidation, superoxide generation, cytokine production and neutrophil accumulation. Topics: Animals; Anticholesteremic Agents; Cholesterol; Colitis; Collagen; Colon; Fatty Acids, Monounsaturated; Fluvastatin; Glutathione; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Indoles; Luminescence; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Simvastatin; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Gliotoxin reduces the severity of trinitrobenzene sulfonic acid-induced colitis in mice: evidence of the connection between heme oxygenase-1 and the nuclear factor-kappaB pathway in vitro and in vivo.
Gliotoxin, a fungal metabolite, has been known to show strong immunosuppressive properties, although its mechanisms are not completely understood. In this report, the authors investigated the mechanism whereby gliotoxin has anti-inflammatory properties in vitro and in trinitrobenzene sulfonic acid-induced colitis.. Body weight, histological scores, and myeloperoxidase activity were evaluated in trinitrobenzene sulfonic acid colitis. Nuclear factor-kappaB (NF-kappaB) p65, tumor necrosis factor-alpha, interleukin (IL)-1beta, IL-12, and intercellular adhesion molecule-1 were detected by immunohistochemical staining. IL-8 secretion was measured by an enzyme-linked immunosorbent assay. Heme oxygenase-1 (HO-1) expression and I-kappaB degradation were analyzed by Western blot.. Pretreatment of human epithelial HT-29 cells with gliotoxin significantly blocked the I-kappaB degradation and NF-kappaB p65 nuclear translocation induced by tumor necrosis factor-alpha or IL-1beta; these were parallel with the inhibition of IL-8 secretion and intercellular adhesion molecule-1 expression in the same cells. Interestingly, gliotoxin induced HO-1 in HT-29 cells and, in turn, inhibition of HO-1 activity by a zinc protoporphyrin IX reversed the effects of gliotoxin in terms of I-kappaB degradation, intercellular adhesion molecule-1 expression, and IL-8 production. In trinitrobenzene sulfonic acid colitis, gliotoxin administration significantly improved the clinical and histopathological symptoms. Notably, gliotoxin also induced HO-1 in the colonic mucosa and zinc protoporphyrin IX reversed the protective effects of gliotoxin in trinitrobenzene sulfonic acid colitis.. These results demonstrate for the first time that the anti-inflammatory actions mediated by gliotoxin include HO-1 induction and the subsequent blockade of NF-kappaB-dependent signaling pathways in vitro and in vivo. The current results also demonstrate that gliotoxin may be an effective agent for the treatment of diseases characterized by mucosal inflammation. Topics: Animals; Anti-Inflammatory Agents; Body Weight; Caco-2 Cells; Colitis; Gliotoxin; Heme Oxygenase-1; Humans; Immunosuppressive Agents; Inflammation; Intercellular Adhesion Molecule-1; Interleukin-8; Mice; NF-kappa B; Peroxidase; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Mechanism underlying the reversal of contractility dysfunction in experimental colitis by cyclooxygenase-2 inhibition.
Inflammatory bowel diseases are associated with reduced colonic contractility and induction of cyclooxygenase-2. In this study a possible role of cyclooxygenase-2 in and the underlying mechanism of the reduced contractility were investigated in experimental colitis. The effects of meloxicam, a cyclooxygenase-2 selective inhibitor were examined on colonic contractility and MAP kinase p38 and ERK(1/2) expression. Colitis was induced in Sprague-Dawley male rats by intra-colonic instillation of trinitrobenzenesulphonic acid (TNBS; 40 mg/rat in 50 ethanol). The animals were divided into three groups. Group 1 (n=9) received meloxicam (3 mg/kg-day) gavage 1 h before and 1 day (Group 2) after induction of colitis. Group 3 (n=9) received phosphate buffered saline (PBS) in a similar manner and served as colitic control. The non colitic control animals received meloxicam in a similar manner. The animals were sacrificed after 5 days of treatment, colon was cleaned with PBS and colonic smooth muscle was obtained which was used in this study. Meloxicam treatment given 1 h before or 1 day after administration of colitis restored the reduced colonic contractility without affecting the sensitivity to carbachol. The levels of colonic smooth muscle IL-1beta mRNA, PGE(2), ERK(1/2), p38, malondialdehyde, myeloperoxidase activity and colonic mass were increased, whereas the body weight was decreased due to TNBS. The changes except colonic muscle mass and p38 expression were reversed by meloxicam treatment. These findings indicate that restoration of reduced colonic contractility by meloxicam is mediated by ERK(1/2), and that ERK(1/2) may serve as an important anti inflammatory target for treatment of colitis. Topics: Animals; Blotting, Western; Carbachol; Colitis; Colon; Cyclooxygenase 2 Inhibitors; Disease Models, Animal; Dose-Response Relationship, Drug; Extracellular Signal-Regulated MAP Kinases; Gastrointestinal Motility; Isometric Contraction; Male; Malondialdehyde; Meloxicam; Muscle, Smooth; p38 Mitogen-Activated Protein Kinases; Peroxidase; Rats; Rats, Sprague-Dawley; RNA, Messenger; Thiazines; Thiazoles; Trinitrobenzenesulfonic Acid | 2006 |
Curcumin regulated shift from Th1 to Th2 in trinitrobenzene sulphonic acid-induced chronic colitis.
To investigate the therapeutic effects of curcumin (Cur) on trinitrobenzene sulphonic acid (TNBS)-induced colitis and the effects of Cur on the balance of Th1/Th2 cytokines.. Colitis was induced by TNBS and treated with Cur (30 mg/kg/d, ip), dexamethasone (Dex, 2 mg/kg/d), or Cur plus dexamethasone (Cur+Dex, 30 mg/kg/d Cur ip+2 mg/kg/d Dex,ip). mRNA in colon mucosa were detected by real-time quantitative polymerase chain reaction. Intracellular cytokines were detected by flow cytometry and concentrations of cytokines in sera were detected by enzyme-linked immunosorbent analysis.. Both Cur and Dex improved body weight loss, ameliorated histological images and decreased macroscopic score and myeloperoxidase activity. Cur decreased the expression of Th1 cytokines (IL-12, IFN-gamma, TNF-alpha, IL-1) and increased the expression of Th2 cytokines (IL-4 and IL-10) in colon mucosa. Cur also increased the proportion of IFN-gamma/IL-4 in splenocytes and circulation. Dex and Cur+Dex decreased the expression of Th1 cytokines but could not increase the expression of Th2 cytokines and the proportion of IFN-gamma/IL-4.. Cur exerted therapeutic effects on colitis by regulating the shift from Th1 to Th2. Topics: Animals; Anti-Inflammatory Agents; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Curcumin; Cytokines; Dexamethasone; Interferon-gamma; Interleukin-12; Intestinal Mucosa; Peroxidase; Rats; Rats, Sprague-Dawley; RNA, Messenger; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Protection from experimental colitis by theaflavin-3,3'-digallate correlates with inhibition of IKK and NF-kappaB activation.
Inflammatory bowel disease (IBD) is associated with activation of nuclear factor kappa B (NF-kappaB) involved in regulating the expression of inducible nitric oxide synthase (iNOS) and proinflammatory cytokine genes. As theaflavin-3,3'-digallate (TFDG), the most potent anti-oxidant polyphenol of black tea, down-regulates NF-kappaB activation, we investigated if TFDG is beneficial in colonic inflammation by suppressing iNOS and proinflammatory cytokines.. The in vivo efficacy of TFDG was assessed in mice with trinitrobenzene sulfonic acid (TNBS)-induced colitis. Both mRNA and protein levels of proinflammatory cytokines and iNOS were analyzed in colon tissue treated with or without TFDG. NF-kappaB activation was determined by electrophoretic mobility shift assay and levels of NF-kappaB inhibitory protein (IkappaBalpha) were analyzed by Western blotting.. Oral administration of TFDG (5 mg kg(-1) daily i.g.) significantly improved TNBS-induced colitis associated with decreased mRNA and protein levels of TNF-alpha, IL-12, IFN-gamma and iNOS in colonic mucosa. DNA binding and Western blotting revealed increase in NF-kappaB activation and IkappaBalpha depletion in TNBS-treated mice from Day 2 through Day 8 with a maximum at Day 4, which resulted from increased phosphorylation of IkappaBalpha and higher activity of IkappaB kinase (IKK). Pretreatment with TFDG markedly inhibited TNBS-induced increases in nuclear localization of NF-kappaB, cytosolic IKK activity and preserved IkappaBalpha in colon tissue.. TFDG exerts protective effects in experimental colitis and inhibits production of inflammatory mediators through a mechanism that, at least in part, involves inhibition of NF-kappaB activation. Topics: Animals; Biflavonoids; Biotransformation; Catechin; Cell Nucleus; Colitis; Cytoplasm; Ether; Female; Flavonoids; Gallic Acid; I-kappa B Proteins; Interferon-gamma; Interleukin-12; Macrophages; Mice; Mice, Inbred BALB C; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Phenols; Polyphenols; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
Anti-inflammatory activity of a pteridine derivative (4AZA2096) alleviates TNBS-induced colitis in mice.
Elevated production of tumor necrosis factor (TNF) plays a central role in the pathogenesis of many inflammatory diseases, such as rheumatoid arthritis and Crohn's disease. Naturally occurring pteridine analogs have been reported to have potent immunomodulatory activity, especially on TNF production. The aim of this study is to identify small molecule TNF inhibitiors derived from pteridine and to prove their in vivo efficacy in an inflammatory model. A focused chemical library based on the pteridine scaffold was screened in vitro on lipopolysaccharide (LPS)-induced TNF production in peripheral blood mononuclear cells (PBMC). One synthetic pteridine analog (4AZA2096), shown to have strong inhibitory activity, was selected and tested for its efficacy to treat trinitrobenzenesulfonate (TNBS)-induced colitis in mice, a model of Crohn's disease. Colitis was induced by rectal administration of 1 mg TNBS in 50% ethanol after presensitization via the skin. The synthetic pteridine analog 4AZA2096 was shown to potently inhibit LPS-induced TNF production in vitro. Colitic mice treated with 4AZA2096 orally (20 mg/kg/day) recovered more rapidly and, histologically, had a reduction of inflammatory lesions, less edema, a reduction of goblet cell loss, and reduced wall thickness. Cell infiltration in the colon, especially infiltration of neutrophils, as shown by myeloperoxidase (MPO) activity, was reduced in 4AZA2096-treated animals. Intralesional TNF production was lower in mice of the treated groups, whereas interleukin-18 (IL-18) and interferon-gamma (IFN-gamma) mRNA were not affected. Treatment had no effect on anti-TNBS antibody production, arguing against generalized immunosuppression. In conclusion, we identified a pteridine derivative, 4AZA2096, with strong inhibitory activity on TNF production and a remission- inducing effect in TNBS colitis, supporting further preclinical and clinical development of this novel TNF inhibitor for treatment of inflammatory diseases. Topics: Animals; Anti-Inflammatory Agents; Antibodies; Cells, Cultured; Colitis; Colon; Cytokines; Humans; Interleukin-1; Leukocytes, Mononuclear; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Peroxidase; Pteridines; RNA, Messenger; T-Lymphocytes; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2006 |
The effect of melatonin on TNBS-induced colitis.
Ulcerative colitis is a multifactorial inflammatory disease of the colon and rectum with an unknown etiology. The present study was undertaken to investigate the effect of melatonin administration on oxidative damage and apoptosis in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Rats were divided into four groups as follows: Group 1 (n=8)-T-NBS colitis; Group 2 (n=8)--melatonin, 10 mg/kg/day ip, for 15 days in addition to TNBS; Group 3 (n=8)--melatonin alone, 10 mg/kg/day ip, for 15 days; and Group 4 (n=8)-isotonic saline solution, 1 ml/rat ip, for 15 days (sham control group). Colonic myeloperoxidase (MPO) activities, malondialdehyde (MDA) levels, and glutathione (GSH) levels are indicators of oxidative damage, while caspase-3 activities reveal the degree of apoptosis of the colonic tissue. In all TNBS-treated rats, colonic MPO activity and MDA levels were found to be increased significantly compared to those in the sham group. Colonic MPO activity and MDA levels were significantly lower in the melatonin treatment group compared to TNBS-treated rats. GSH levels of colonic tissues were found to be significantly lower in TNBS-treated rats compared to the sham group. Treatment with melatonin significantly increased GSH levels compared to those in TNBS-treated rats. Caspas-3 activity of colonic tissues was found to be significantly higher in TNBS-treated rats compared to the sham group. Treatment with melatonin significantly decreased caspase-3 activity compared to that in TNBS-treated rats. These results imply a reduction in mucosal damage due to anti-inflammatory and anti-apoptotic effects of melatonin. Topics: Analysis of Variance; Animals; Antioxidants; Apoptosis; Caspase 3; Caspases; Colitis; Colon; Glutathione; Intestinal Mucosa; Male; Malondialdehyde; Melatonin; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2006 |
PepT1 mediates colon damage by transporting fMLP in rats with bowel resection.
The intestinal oligopeptide transporter (PepT1) is responsible for the absorption of nutrient di-tripeptide and mediates the transportation of bacterial product N-formylmethionylleucyl-phenylalanine (fMLP) that induces intestinal inflammation. PepT1 is absent from normal colon epithelia but is abnormally expressed in the colon of patients with inflammatory bowel diseases. This study was designed to investigate the role of PepT1 in colonic inflammation and its relation with fMLP.. PepT1 mRNA expression was analyzed by RT-PCR and oligopeptide transportation was quantified by the luminal perfusion with cephalexin in rats following 80% small bowel resection. The inflammatory effects of PepT1-mediated fMLP transport were also investigated by the measurement of myeloperoxidase (MPO) activity, histological analysis, and the use of Gly-Gly (Glycine-Glycine, a competitive PepT1 blocker).. The overexpression of PepT1 was observed, peaking at 2 weeks post-operation, with its levels declining to 12% at week 4. The ability of oligopeptide transport was correlated with the PepT1 levels. The fMLP perfusion into the colon of rats with bowel resection resulted in an increased MPO activity and mucosal inflammation at week 2, but not at week 4 post-operation. The administration of Gly-Gly (50 mm) competitively inhibited PepT1, reducing the fMLP-associated MPO activation and colonic mucosal damage.. The colonic PepT1 overexpression induced by bowel resection increases the transport of bacterial product fMLP and hence causes colonic inflammation, which may serve as a previously unrecognized pathway resulting in colon mucosa damage. Topics: Animals; Anti-Bacterial Agents; Cephalexin; Colitis; Glycylglycine; Intestinal Absorption; Intestinal Mucosa; Intestine, Small; Male; N-Formylmethionine Leucyl-Phenylalanine; Peptide Transporter 1; Peroxidase; Rats; Rats, Sprague-Dawley; RNA, Messenger; Symporters | 2006 |
Interferon-gamma is causatively involved in experimental inflammatory bowel disease in mice.
Cytokines may be crucially involved in the pathogenesis of inflammatory bowel diseases (IBD), but it remains controversial whether interferon (IFN)-gamma, a typical proinflammatory cytokine, is an essential mediator to cause the disorders. In the present study, IFN-gamma(-/-) and wild-type (WT) C57BL/6 mice were fed 2.5% dextran sodium sulphate (DSS) in drinking water for 7 days, in order to investigate DSS-induced intestinal inflammation. The DSS-treated WT mice exhibited a robust production of IFN-gamma in the gut, a remarkable loss of body weight, as well as high rate of mortality (60%). In striking contrast, IFN-gamma deficient mice did not develop DSS-induced colitis, as indicated by the maintenance of body weight and survival rate of 100%. Severe intestinal inflammation was demonstrated exclusively in WT animals in terms of the shortening of the bowel as well as the elevation of the disease activity index, myeloperoxidase (MPO) activity and serum haptoglobin level. Histological study of DSS-treated WT intestine revealed disruption of mucosal epithelium and massive infiltration of inflammatory cells, while the organ from IFN-gamma(-/-) mice remained virtually normal in appearance. Enzyme-linked immunosorbent assay (ELISA) analyses indicated abundant production of three chemokines, i.e. monokine induced by interferon-gamma (MIG), interferon-inducible protein 10 (IP-10) and monocyte chemoattractant protein-1 (MCP-1), in the DSS-irritated intestine of WT but not of IFN-gamma(-/-) mice. The present results demonstrate clearly that IFN-gamma plays indispensable roles in the initiation of DSS colitis, and some chemokines are produced in an IFN-gamma-dependent fashion. Topics: Acute Disease; Animals; Chemokine CCL2; Chemokine CXCL10; Chemokine CXCL9; Chemokines, CXC; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Disease Susceptibility; Interferon-gamma; Mice; Mice, Inbred C57BL; Peroxidase; Severity of Illness Index; Weight Loss | 2006 |
Different susceptibilities of spontaneous rhythmicity and myogenic contractility to intestinal muscularis inflammation in the hapten-induced colitis.
We examined the time-dependent changes in the immunoreactivity of the smooth muscle region and the accompanying motility disorder in a hapten-induced rat model of colitis. Histological analysis and myeloperoxidase (MPO) activity indicated that inflammatory cells infiltrated into the muscle layer at 2 days after 2,4,6-trinitrobenzenesulphonic acid (TNBS) treatment. The infiltrated immune cells then gradually decreased in number, but were still present at 14 days. The expression of proinflammatory cytokine mRNAs (TNF-alpha, IL-1beta and IL-6) and proteins in the muscle layer was increased at 2 days, then began to decrease, returning to control levels at 14 days. The frequency of spontaneous rhythmicity was suppressed at 2 and 7 days, and returned to control levels at 14 days. Consistent with these observations, the immunoreactivity of the interstitial cells of Cajal network was disrupted at 2 and 7 days, which then gradually reformed at 14 days. On the other hand, the myogenic contractions induced by high K(+) and carbachol were decreased at 2 days, and were still inhibited at 14 days. These results suggest that spontaneous rhythmicity dysfunction may improve more rapidly than myogenic contractility dysfunction in a hapten-induced rat model of colitis. Topics: Animals; Colitis; Cytokines; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Gastrointestinal Motility; Gene Expression; Haptens; Immunohistochemistry; Inflammation; Intestinal Mucosa; Male; Muscle Contraction; Muscle, Smooth; Peroxidase; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Time Factors; Trinitrobenzenesulfonic Acid | 2006 |
Bifidobacterium infantis strains with and without a combination of oligofructose and inulin (OFI) attenuate inflammation in DSS-induced colitis in rats.
Pathogenesis of inflammatory bowel disease is thought to be through different factors and there is a relationship between the gut flora and the risk of its development. Probiotics can manipulate the microflora in chronic inflammation and may be effective in treating inflammation. Bifidobacterium are saccharolytic and their growth in the gut can be promoted by non-absorbable carbohydrates and its increase in the colon appears to be of benefit.. Oligofructose and inulin (OFI) alone and the two B. infantis DSM 15158 and DSM 15159 with and without OFI, were fed to Sprague-Dawley rats for 7 days prior to colitis induction and administrations continued for another 7 days with the DSS. Colitis severity assessed using a Disease Activity Index. Samples were collected 7 days after colitis induction, for intestinal bacterial flora, bacterial translocation, short chain fatty acids (SCFAs), myeloperoxidase (MPO), cytokines (IL-1beta, TNF-alpha, IL-10 and TGF-beta) and malondialdehyde (MDA).. OFI alone or the B. infantis strains with and without OFI improved significantly the DAI and decreased colonic MPO activity. Colonic tissue IL-1beta decreased significantly in all treated groups except B. infantis DSM 15158. MDA decreased significantly in B. infantis DSM 15159 with and without OFI compared to colitis control. Succinic acid increased significantly in OFI group with and without DSM 15159 compared to all groups. Sum values of propionic, succinic acid and butyric acid increased significantly in all groups compare to the colitis control. Bacterial translocation to mesenteric lymph nodes decreased significantly in all groups compared to colitis control. Translocation to the liver decreased significantly in all groups compare to the colitis control and OFI + B. infantis DSM 15158 groups.. Administrations of OFI and Bifidobacterium improve DSS-induced acute colitis and have an anti-inflammatory effect. Major differences in effect were observed between the two B. infantis strains as indicated in MDA and succinic acid concentration as well as bacterial translocation rate in synbiotic combinations. Topics: Animals; Bacterial Translocation; Bifidobacterium; Cecum; Colitis; Colon; Colony Count, Microbial; Cytokines; Dextran Sulfate; Fatty Acids, Volatile; Inulin; Lactates; Lipid Peroxidation; Oligosaccharides; Peroxidase; Probiotics; Rats; Rats, Sprague-Dawley; Severity of Illness Index; Species Specificity; Succinic Acid | 2006 |
Improvement of an experimental colitis in rats by lactic acid bacteria producing superoxide dismutase.
The use of superoxide dismutases (SODs) in inflammatory diseases is hampered by their short circulatory half-life. To determine whether a bacterial supply of SOD into the colon might improve an experimental colitis, the effects of oral treatment with live recombinant lactic acid bacteria producing different amounts of SOD and those of colonic infusion of SOD were compared. Wistar rats were fitted with a catheter in the proximal colon through which TNBS was administered to induce colitis. Animals received a continuous intracolonic infusion of bovine SOD (40 U per rat per day) for 4 days after TNBS or were treated orally with live recombinant Lactococcus lactis or Lactobacillus plantarum strains (10 colony-forming units (CFU)/d), producing or not producing SOD, for 4 days before and after TNBS. SOD activity of bacterial extracts was 0, 26, 74, and 624 units/10 CFU for L. plantarum, L. lactis, L. lactis SOD, and L. plantarum SOD, respectively. Four days after TNBS, macroscopic and microscopic damage, myeloperoxidase (MPO) activity, and nitrotyrosine immunostaining were evaluated. TNBS induced macroscopic and microscopic damages, an increase in MPO activity, and intense immunostaining for nitrotyrosine. Macroscopic damage and MPO activity were reduced by bovine SOD. These parameters and microscopic damages also were reduced by L. lactis, L. lactis SOD, and L. plantarum SOD, but not by L. plantarum. Nitrotyrosine immunostaining was attenuated after treatment with the 4 bacterial strains. Although not all of the anti-inflammatory effects could be attributed directly to SOD, our results suggest that SOD-producing lactic acid bacteria open a novel approach in inflammatory bowel disease treatment. Topics: Administration, Oral; Animals; Cattle; Colitis; Immunohistochemistry; Lactobacillus; Male; Peroxidase; Probiotics; Random Allocation; Rats; Rats, Wistar; Superoxide Dismutase; Trinitrobenzenesulfonic Acid | 2006 |
Preventive effect of a pectic polysaccharide of the common cranberry Vaccinium oxycoccos L. on acetic acid-induced colitis in mice.
To study isolation and chemical characterization of pectin derived from the common cranberry Vaccinium oxycoccos L. (oxycoccusan OP) and the testing of its preventive effect on experimental colitis.. Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4% Evans blue passage after i.p. injection of 0.05 mol/L acetic acid.. In the mice treated with OP, colonic macroscopic scores (1.1+/-0.4 vs 2.7, P<0.01) and the total square area of damage (10+/-2 vs 21+/-7, P<0.01) were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons (42+/-11 vs 112+/-40, P<0.01) and enhance the amount of mucus of colitis mice (0.9+/-0.1 vs 0.4+/-0.1, P<0.01). The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice (3.6+/-0.7 vs 5.1+/-0.8, P<0.01). OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability (161+/-34 vs 241+/-21, P<0.01). Adhesion of peritoneal neutrophils and macrophages was also shown to decrease after administration of OP (141+/-50 vs 235+/-37, P<0.05).. Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP, on acetic acid-induced colitis in mice was detected. A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan. Topics: Acetic Acid; Animals; Antioxidants; Cell Adhesion; Colitis; Colon; Disease Models, Animal; Intestinal Mucosa; Male; Malondialdehyde; Mice; Mice, Inbred A; Neutrophils; Pectins; Peroxidase; Phytotherapy; Plant Preparations; Vaccinium | 2006 |
Citrobacter rodentium infection causes iNOS-independent intestinal epithelial dysfunction in mice.
Attaching-effacing bacteria are major causes of infectious diarrhea in humans worldwide. Citrobacter rodentium is an attaching-effacing enteric pathogen that causes transmissible murine colonic mucosal hyperplasia. We characterized colonic inflammation and ion transport at 3, 7, 10, 30, and 60 d after infection of C57Bl/6 mice with C. rodentium. Macroscopic damage score was significantly increased 7 and 10 d after infection. Colonic wall thickness was increased at 7, 10, 30, and 60 d. Myeloperoxidase (MPO) activity was significantly increased at 3, 7, and 10 d and returned to control levels by days 30 and 60. The expressions of inducible nitric oxide synthase and cyclooxygenase-2 were increased by C. rodentium infection. Significant reductions in the epithelial secretory response to carbachol, but not to electrical field stimulation or forskolin, were observed at 3 and 10 d of infection. Translocation of enteric bacteria into the mesenteric lymph nodes was observed 10 d following infection. There was no difference in response to infection between animals deficient in inducible nitric oxide synthase and wild-type controls. The COX-2 inhibitor rofecoxib caused decreased wall thickness and MPO activity at day 10. However, COX-2 inhibition did not alter infection-induced changes in ion transport. Citrobacter rodentium infection causes colonic inflammation, mucosal hyperplasia, and nitric-oxide-independent epithelial dysfunction in association with increased permeability to luminal bacteria. Topics: Animals; Bacterial Translocation; Carbachol; Cell Membrane Permeability; Cholinergic Agonists; Citrobacter rodentium; Colitis; Colon; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Enterobacteriaceae Infections; Hyperplasia; Intestinal Mucosa; Intestinal Secretions; Ion Transport; Lactones; Lymph Nodes; Mice; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide Synthase Type II; Peroxidase; Sulfones; Time Factors | 2006 |
Uterine motor alterations and estrous cycle disturbances associated with colonic inflammation in the rat.
The impact of colitis on uterine contractility and estrous cycle was investigated after intracolonic administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats. Colitis severity was assessed by macroscopic damage scoring (MDS) 4 days after TNBS, and myeloperoxidase (MPO) activity was measured in both colon and uterus of control and colitic rats. Estrous cycle stages were determined by vaginal smears and histology, and uterine contractility was assessed in vitro on longitudinal and circular strips. In control rats, uterine MPO activity varied markedly during the cycle and peaked around estrus. In rats with moderate colitis [MDS < 5, 3.1 +/- 0.2 (mean +/- SE)], uterine MPO decreased by 61% compared with estrus control, without disruption of the cycle. Frequency of spontaneous contractions was reduced by 32% in circular muscle. Contractile responses to KCl and carbachol were not affected, whereas maximal response to oxytocin decreased by 47% in the longitudinal muscle. In rats with severe colitis (MDS > 5, 6.0 +/- 0.2), uterine MPO was reduced by 96% and estrous cycle was disrupted. Spontaneous contractility was impaired in circular strips, and a 39% decrease in the contraction frequency occurred in the longitudinal strips. Circular strips did not contract to KCl or carbachol; however, longitudinal strips had maximal responses to KCl, carbachol, and oxytocin reduced by 36%, 27%, and 46%, respectively. Estrogen replacement protected the uterine responses to carbachol in colitic rats, whereas oxytocin responses remained depressed. These data indicate that colonic inflammation can influence both spontaneous and evoked uterine contractility, in relation to estrous cycle disturbances, impaired estradiol production, and functional alterations of myometrial cells. Topics: Animals; Carbachol; Colitis; Colon; Estrus; Female; In Vitro Techniques; Muscarinic Agonists; Oxytocin; Peroxidase; Potassium Chloride; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid; Uterine Contraction; Uterus | 2005 |
Ameliorating effect of hepatocyte growth factor on inflammatory bowel disease in a murine model.
Hepatocyte growth factor (HGF), a multifunctional cytokine, accelerates intestinal epithelial proliferation. We studied the effects of HGF in mice with trinitrobenzene sulfonic acid-induced colitis, which shows clinical and molecular resemblance to Crohn's disease. Mice with colitis repeatedly were transfected intramuscularly with human HGF cDNA. Weight, survival, histopathology, proinflammatory cytokine mRNAs, and leukocyte infiltration were assessed. Treatment with HGF cDNA induced tyrosine phosphorylation of intestinal c-Met/HGF receptors, inhibited apoptosis, and promoted mitosis in intestinal epithelial cells, accelerating intestinal epithelial restoration and suppressing inflammation. Transfection with HGF cDNA markedly suppressed intestinal mRNA expression of T-helper 1 cytokines such as interleukin-12 and -1beta, interferon-gamma, and tumor necrosis factor-alpha. Numbers of total and CD4-positive T cells, neutrophils, and myloperoxidase activity in intestinal epithelium were diminished by HGF gene transfer, which also prevented weight loss, and improved survival. HGF might prove useful for controlling inflammatory bowel disease. Topics: Animals; Apoptosis; Colitis; Colon; Cytokines; Hepatocyte Growth Factor; Humans; Intestinal Mucosa; Male; Mice; Mice, Inbred BALB C; Peroxidase; RNA, Messenger; Transfection; Trinitrobenzenesulfonic Acid; Weight Loss | 2005 |
Myenteric plexus injury and apoptosis in experimental colitis.
Intestinal inflammatory conditions are associated with structural and functional alterations of the enteric nervous system (ENS). While injury to the enteric nervous system is well described, the mechanisms of neuronal injury and neuronal cell loss remain unclear. The aim of the present study was to examine the neural consequences of distal colitis and to assess the role of neutrophil granulocytes in mediating these changes. Colitis was induced in C3H/HEN female mice with dinitrobenzene sulfonic acid. The mice were then sacrificed at 0.5, 1, 1.5, 2, 3, 4, 6, 12, 24, 120 h post instillation of dinitrobenzene sulfonic acid. The inflammatory response was assessed by macroscopic damage score, myeloperoxidase activity and histology. HuC/D and PGP 9.5 immunostaining was used to examine myenteric plexus density and structure, neural cell body numbers and distribution in cross-section and whole mount preparations. Apoptosis was investigated in whole mount preparations double stained with HuC/D and activated caspase-3 or cleaved poly (ADP-ribose) polymerase (PARP). Dinitrobenzene sulfonic acid-induced colitis was associated with a rapid and significant loss of HuC/D immunoreactive myenteric plexus neuronal cell bodies (42% decrease relative to control) that remained unchanged between 6 and 120 h. No change in myenteric plexus density was observed with PGP 9.5 immunostaining. Neuronal apoptosis was evident between 0.5 and 3 h. PARP immunoreactive neurons ranged between 1% and 2.5%. Colitis was associated with significant impairment in colonic propulsive function. Pre-treatment of mice with anti-neutrophil serum attenuated the inflammatory response and partially reduced the extent of myenteric plexus neuronal cell loss. Taken together, these data suggest that acute colitis is associated with loss of myenteric plexus neurons that is partly mediated by neutrophil granulocyte infiltration and is accompanied by impairment of colonic motility. Topics: Animals; Antibodies, Antineutrophil Cytoplasmic; Apoptosis; Benzenesulfonates; Caspase 3; Caspases; Cell Count; Colitis; Disease Models, Animal; ELAV Proteins; ELAV-Like Protein 3; Female; Immunohistochemistry; Membrane Glycoproteins; Mice; Mice, Inbred C3H; Myenteric Plexus; Nerve Tissue Proteins; Neurons; Peroxidase; RNA-Binding Proteins; Statistics, Nonparametric; Time Factors; Ubiquitin Thiolesterase | 2005 |
Oxytocin ameliorates oxidative colonic inflammation by a neutrophil-dependent mechanism.
Oxytocin (OT), a nonapeptide produced in the paraventricular and the supraoptical nuclei in the hypothalamus has a wide range of effects in the body. However, the role of OT on the gastrointestinal (GI) tract has to be settled. OT may participate in the regulation of motility, secretion, blood flow, cell turnover and release of neurotransmitters and/or peptides in the GI tract, possesses antisecretory and antiulcer effects, facilitates wound healing and is involved in the modulation of immune and inflammatory processes. The present work was conducted to assess the possible therapeutic effects of OT against the acetic acid-induced colonic injury in the rat.. Colitis was induced by intracolonic administration of acetic acid (5%) in Sprague-Dawley rats (200-250 g). Either saline or OT (0.5 mg/kg) was injected subcutaneously, immediately after the induction of colitis and repeated two times a day for 4 days. On the 4th day, rats were decapitated and distal 8 cm of the colon were removed for the macroscopic and microscopic damage scoring, determination of tissue wet weight index (WI), malondialdehyde (MDA) levels, an end product of lipid peroxidation; glutathione (GSH) levels, a key antioxidant; and myeloperoxidase (MPO) activity, as an indirect index of neutrophil infiltration. Colonic collagen content, as a fibrosis marker was also determined. Lactate dehydrogenase (LDH) and tumor necrosis factor-alpha (TNF-alpha) levels were assayed in serum samples. In the acetic acid-induced colitis, macroscopic and microscopic damage scores, WI, MDA and MPO levels were significantly increased, while GSH levels were decreased when compared to control group (p <0.05-<0.001). Treatment with OT abolished the colitis-induced elevations in damage scores, WI, MDA and MPO levels and restored the GSH levels (p <0.05-0.001). Similarly, acetic acid increased the collagen content of colonic tissues and OT-treatment reduced this value to the level of the control group. Serum LDH and TNF-alpha levels were also elevated in the acetic acid-induced colitis group as compared to control group, while this increase was significantly decreased by OT treatment. The results suggest that OT, which improves the antioxidative state of the colonic tissue and ameliorates oxidative colonic injury via a neutrophil-dependent mechanism, requires further investigation as a potential therapeutic agent in colonic inflammation. Topics: Acetic Acid; Animals; Antioxidants; Colitis; Colon; Female; Gastrointestinal Tract; Glutathione; Immune System; Inflammation; L-Lactate Dehydrogenase; Lipid Peroxidation; Neutrophils; Oxidants; Oxidation-Reduction; Oxygen; Oxytocin; Peroxidase; Rats; Rats, Sprague-Dawley; Time Factors; Tumor Necrosis Factor-alpha | 2005 |
Regional intestinal adaptations in Na+,K+-ATPase in experimental colitis and the contrasting effects of interferon-gamma.
This study evaluated Na+,K+-ATPase activity and the abundance of alpha1 subunit Na+,K+-ATPase in experimental colitis and gathered evidence on the effects of interferon-gamma (IFN-gamma) on intestinal Na+,K+-ATPase.. Colitis was induced by the intrarectal administration of 2,4,6-trinitrobenzene sulphonic acid (TNBS, 30 mg/250 microL). Na+,K+-ATPase activity was determined as the difference between total and ouabain-insensitive ATPase. The abundance of Na+,K+-ATPase was analysed by immunoblotting.. Na+,K+-ATPase activity was markedly reduced in the proximal colonic mucosa of TNBS-treated rats, whereas upstream in the terminal ileal mucosa a marked increase in sodium pump activity was observed. At the jejunal level no significant changes in Na+,K+-ATPase activity were observed between TNBS-treated rats and corresponding controls (ethanol-treated rats). No changes were observed in the abundance of alpha1 subunit Na+,K+-ATPase in the proximal colon, terminal ileum and jejunum. The administration of IFN-gamma (50,000 U) 48 h before sacrifice reduced both Na+,K+-ATPase activity and the abundance of alpha1 subunit Na+,K+-ATPase in the proximal colon. Dexamethasone prevented colonic inflammation and decreases in proximal colonic Na+,K+-ATPase activity in TNBS-treated rats, but did not affect the INF-gamma-induced decrease in colonic Na+,K+-ATPase activity.. The increase in ileal Na+,K+-ATPase activity upstream to the lesioned colonic mucosa, where Na+,K+-ATPase activity was markedly reduced, might indicate a compensatory process to counteract the decrease in water and electrolyte absorption at the colonic level. This decrease in colonic Na+,K+-ATPase activity is likely not related to INF-gamma-induced downregulation of Na+,K+-ATPase. Topics: Animals; Antineoplastic Agents; Caco-2 Cells; Colitis; Colon; Dexamethasone; Epithelial Cells; Humans; Ileum; Interferon-gamma; Intestinal Mucosa; Jejunum; Lower Gastrointestinal Tract; Male; Peroxidase; Rats; Rats, Wistar; Sodium-Potassium-Exchanging ATPase | 2005 |
Therapeutic potential of follistatin for colonic inflammation in mice.
Activins belong to the transforming growth factor-beta superfamily. Recent studies have shown that activin and its natural antagonist, follistatin, are involved in tissue repair and inflammatory processes. The aim of this study was to determine whether neutralization of activins with follistatin would have an in vivo anti-inflammatory effect in several murine models of colitis.. We assessed activin levels in the colitis induced by intracolonic administration of trinitrobenzene sulfonic acid (TNBS). We subsequently tested the effects of an intraperitoneal injection of follistatin before or after induction of TNBS colitis. We also examined the established colitis induced by oral dextran sulfate sodium (DSS) as well as the spontaneous colitis that develops in interleukin (IL)-10 gene-deficient (IL-10 -/- ) mice.. Levels of activin transcripts in the colon during the acute phase of TNBS colitis were up-regulated. Epithelial cells, infiltrating macrophages (Mvarphi), and endothelial cells produced excess activin betaA. Pretreatment with follistatin increased the survival rate of mice with TNBS colitis from 33% to 82% and decreased the plasma levels of IL-6 and amyloid A. Administration of follistatin also reduced the histologic score and tissue myeloperoxidase activity in established TNBS and DSS colitis and reduced the severity of the colitis in IL-10 -/- mice. Based on results obtained from 3 mouse models and from in vitro experiments, follistatin promoted the proliferation of colonic epithelial cells.. Neutralization of activins by follistatin promoted epithelial cell division and tissue repair, clearly suggesting a treatment modality for intestinal inflammation. Topics: Animals; Colitis; Colonic Diseases; Female; Follistatin; Inflammation; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Trinitrobenzenesulfonic Acid | 2005 |
Induction of colitis in young rats by dextran sulfate sodium.
Models using dextran sulfate sodium (DSS) to induce experimental colitis in rodents have been performed mostly in adult animals. For this reason, we aimed to develop a model of colitis in young rats. DSS was administered to 30-day-old rats at concentrations ranging from 0.5 to 5% in drinking water. Young rats were remarkably sensitive to DSS since clinical symptoms rapidly rose with 5% DSS and most animals died after the fifth day. With 1 and 2% DSS, the severity of mucosal lesions was also high on day 7, the animals showing leukocytosis and anemia. At 0.5% DSS, leukocytosis and mild colonic lesions were induced. This concentration of DSS significantly increased myeloperoxidase activity and goblet cell number in the colon, indicating mucosal inflammation. Since food consumption was not reduced by 0.5% DSS, we suggest that this protocol can be used to study the effects of dietary supplements on intestinal inflammatory processes. Topics: Acute Disease; Administration, Oral; Anemia; Animals; Animals, Newborn; Cell Count; Colitis; Colon; Dextran Sulfate; Dose-Response Relationship, Drug; Goblet Cells; Intestinal Mucosa; Leukocytosis; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Survival Analysis | 2005 |
Intestinal responsiveness to experimental colitis in young rats is altered by maternal diet.
Increasing evidence suggests that fetal and neonatal nutrition impacts later health. Aims of the present study were to determine the effect of maternal dietary fat composition on intestinal phospholipid fatty acids and responsiveness to experimental colitis in suckling rat pups. Female rats were fed isocaloric diets varying only in fat composition throughout gestation and lactation. The oils used were high (8%) in n-3 [canola oil (18:3n-3)], n-6 (72%) [safflower oil (18:2n-6)], or n-9 (78%) [high oleic acid safflower oil (18:1n-9)] fatty acids, n = 6/group. Colitis was induced on postnatal day 15 by intrarectal 2,4-dinitrobenzene sulfonic acid (DNBS) administration with vehicle (50% ethanol) and procedure (0.9% saline) controls. Jejunal and colonic phospholipids and milk fatty acids were determined. The distal colon was assessed for macroscopic damage, histology, and MPO activity. The 18:2n-6 maternal diet increased n-6 fatty acids, whereas the 18:3n-3 diet increased n-3 fatty acids in milk and pup jejunal and colonic phospholipids. Maternal diet, milk, and pup intestinal n-6-to-n-3 fatty acid ratios increased significantly in order: high 18:3n-3 < high 18:1n-9 < high 18:2n-6. DNBS administration in pups in the high 18:2n-6 group led to severe colitis with higher colonic damage scores and MPO activity than in the 18:1n-9 and 18:3n-3 groups. High maternal dietary 18:3n-3 intake was associated with colonic damage scores and MPO activity, which were not significantly different from ethanol controls. We demonstrate that maternal dietary fat influences the composition of intestinal lipids and responsiveness to experimental colitis in nursing offspring. Topics: Animal Feed; Animals; Animals, Suckling; Colitis; Colon; Dietary Fats; Fatty Acids; Female; Jejunum; Lactation; Milk; Peroxidase; Phospholipids; Rats; Rats, Sprague-Dawley | 2005 |
Preventative effects of lactulose in the trinitrobenzenesulphonic acid model of rat colitis.
Lactulose is a drug used as a laxative that has been shown to promote the growth of lactobacilli and bifidobacteria, acting as a prebiotic and with a potential beneficial effect in inflammatory bowel disease. The present study describes the preventive antiinflammatory activity of lactulose in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis.. Rats were rendered colitic by a colonic instillation of 10 mg of TNBS dissolved in 0.25 mL of 50% ethanol. One group of colitic rats received lactulose, which was incorporated in the drinking water (2.5% wt/vol) for 2 weeks before TNBS instillation, and colonic damage was evaluated 1 week after colitis induction. Different biochemical markers of colonic inflammation were assayed: myeloperoxidase activity, glutathione content, tumor necrosis factor alpha, leukotriene B4 levels, and colonic inducible nitric oxide synthase expression. In addition, bacterial counts (for lactobacilli and bifidobacteria) were performed in colonic contents from colitic rats.. The results show that lactulose exerted a preventive antiinflammatory effect in this model of rat colitis, as evidenced by a significant reduction of myeloperoxidase activity and by a decrease of both colonic tumor necrosis factor alpha and leukotriene B4 production. This effect was also characterized by an inhibition of colonic inducible nitric oxide synthase expression, which is unregulated as a consequence of the inflammatory status. This beneficial effect was associated with increased levels of lactobacilli and bifidobacteria species in colonic contents in comparison with untreated colitic rats.. In conclusion, the intestinal antiinflammatory effect of lactulose could be related to its prebiotic properties, supporting its potential use in human inflammatory bowel disease. Topics: Animals; Colitis; Disease Models, Animal; Female; Gastrointestinal Agents; Lactobacillaceae; Lactulose; Leukotriene B4; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2005 |
Effect of the macrolide antibacterial drug, tylosin, on TNBS-induced colitis in the rat.
Bacterial antigens, such as intestinal microflora, are known to play a role in the pathogenesis of human inflammatory bowel disease (IBD). Tylosin, a macrolide antimicrobial agent, has proven to be effective in cat and dog chronic colitis, but the reasons underlying this efficacy are still unclear. In the present study we evaluated the effects of tylosin on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in the rat, in comparison with the antibacterial drug metronidazole and the corticosteroid budesonide. Colitis was induced by a single intrarectal administration of 10 mg TNBS under light ether anesthesia. Tylosin (20 mg/kg twice a day), metronidazole (160 mg/kg twice a day) and budesonide (500 microg/kg once a day) were given orally for up to 6 days to separate groups of rats. The animals were sacrificed after 6 days and colonic lesions evaluated (colon weight, macroscopic and histologic damage, myeloperoxidase activity). Tylosin and metronidazole significantly lowered macroscopic lesion score, reduced colon weight, the severity of histologic lesions and myeloperoxidase activity; budesonide did not significantly change the parameters of colonic inflammation. These data indicate a protective effect of tylosin against intestinal inflammation, suggesting a major role for bacteria, anaerobes in particular, in the development of TNBS-induced mucosal damage. Topics: Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents; Budesonide; Colitis; Colon; Disease Models, Animal; Male; Metronidazole; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tylosin | 2005 |
A potent and selective inhibitor of group IIa secretory phospholipase A2 protects rats from TNBS-induced colitis.
Secretory phospholipase A(2) (sPLA(2)) enzymes have been implicated in the pathogenesis of human inflammatory bowel disease (IBD). In this study we compared the efficacy of a potent, new and highly selective inhibitor of group IIa human sPLA(2) enzyme (5-(4-benzyloxyphenyl)-4S-(7-phenylheptanoylamino)-pentanoic acid; sPLA(2)I), with that of sulfasalazine, in a rat model of trinitrobenzene sulfonic acid (TNBS)-induced colitis. Following a single oral dose of sPLA(2)I (5 mg/kg), pharmacoactive levels of drug were detected in the serum within 15 min and for up to 24 h by liquid chromatography mass spectrometry analysis. Rats treated with sPLA(2)I (5 mg/kg/day) prior to induction of colitis were significantly healthier than TNBS-alone rats, as shown by reduced mortality, improved food intake and increased body weight, and significantly reduced colon myeloperoxidase levels, edema, tumour necrosis factor-alpha levels, and colon macroscopic pathology scores after 8 days. Rats pretreated with sulfasalazine (100 mg/kg/day) also had reduced disease expression markers similar to the sPLA(2)I, but exhibited no improvement in colon edema. This study supports a role for the group IIa sPLA(2) enzyme in pathology associated with the TNBS rat model of IBD, and suggests a possible therapeutic application for selective inhibitors of group IIa sPLA(2) inhibitors in the treatment of IBD. Topics: Animals; Body Weight; Colitis; Disease Models, Animal; Eating; Edema; Enzyme Inhibitors; Female; Group II Phospholipases A2; Humans; Hypertension; Inflammatory Bowel Diseases; Lipopolysaccharides; Neutropenia; Pentanoic Acids; Peroxidase; Phospholipases A; Phospholipases A2; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2005 |
Expression and significance of nuclear factor kappaB p65 in colon tissues of rats with TNBS-induced colitis.
To investigate the role of NF-kappaB in the pathogenesis of TNBS-induced colitis in rats.. Thirty-two healthy adult Sprague-Dawley (SD) rats were randomly divided into four groups of eight each: normal, NS, model I, model II groups in our study. Rat colitis model was established through 2-,4-,6-trinitrobenzene sulfonic acid (TNBS) enema. At the end of four weeks, the macroscopical and histological changes of the colon were examined and mucosa myeloperoxidase (MPO) activities assayed. NF-kappaB p65 expression was determined by Western blot assessment in cytoplasmic and nuclear extracts of colon tissue, and the expressions of TNF-alpha and ICAM-1 protein in colon tissue were examined by immunohistochemistry. The relativities between expression of NF-kappaB p65 and other parameters were analyzed.. TNBS enema resulted in pronounced pathological changes of colonic mucosa in model II group (macroscopic and histological injury indices 6.25+/-1.39 and 6.24+/-1.04, respectively), which were in accordance with the significantly elevated MPO activity (1.69+/-0.11). And the nuclear level of NF-kappaB and expression of TNF-alpha, ICAM-1 in rats of model II group were higher than that of normal control (9.7+/-1.96 vs 1.7+/-0.15, 84.09+/-14.52 vs 16.03+/-6.21, 77.69+/-8.09 vs 13.41+/-4.91 P<0.01), Linear correlation analysis revealed that there were strong correlations between the nuclear level of NF-kappaB and the tissue positive expression of TNF-alpha and ICAM-1, MPO activities, macroscopical and histological indices in TNBS-induced colitis, respectively (r = 0.8235, 0.8780, 0.8572, 0.9152, 0.8247; P<0.05).. NF-kappaB plays a pivotal role in the pathogenesis of ulcerative colitis, which might account for the up-regulation the expression of TNF-alpha and ICAM-1. Topics: Animals; Blotting, Western; Colitis; Colon; Female; Immunohistochemistry; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Male; NF-kappa B; Peroxidase; Rats; Rats, Sprague-Dawley; Transcription Factor RelA; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2005 |
Transgenic over-expression of macrophage migration inhibitory factor renders mice markedly more susceptible to experimental colitis.
Enhanced production of macrophage migration inhibitory factor (MIF) is recognized in patients with inflammatory bowel disease (IBD) and mice with experimental colitis; however, the precise molecular function of MIF in colitis is not fully understood. To further investigate this matter, we examined the pathological features of MIF transgenic mice with dextran sulphate sodium (DSS)-induced colitis. We generated transgenic mice carrying a murine MIF cDNA driven by a cytomegalovirus enhancer and a beta-actin/beta-globin promoter. Mice were orally administered 1-4% DSS in drinking water for 7 days. Clinical disease activity, survival and histological features were evaluated. The level of myeloperoxidase (MPO) activity in the colon tissue was measured to assess neutrophil infiltration. The level of corticosterone in the serum was measured by enzyme linked-immunosorbent assay (ELISA). MIF mRNA and protein were markedly up-regulated in the colon and serum obtained from MIF transgenic mice. The severity of the colitis induced by 1% DSS treatment was markedly higher in MIF transgenic mice than in wild-type mice. We also found that MPO activity was significantly higher in MIF transgenic mice than wild-type mice in response to DSS stimulation. Interestingly, the corticosterone level remained unchanged in MIF transgenic mice. MIF enhances DSS-induced colitis, in part via neutrophil accumulation and inhibition of glucocorticoid bioactivity. Topics: Animals; Colitis; Colon; Corticosterone; Dextran Sulfate; Disease Susceptibility; Macrophage Migration-Inhibitory Factors; Mice; Mice, Inbred C57BL; Mice, Inbred ICR; Mice, Transgenic; Neutrophil Infiltration; Peroxidase; RNA, Messenger; Severity of Illness Index | 2005 |
5-Lipoxygenase modulates colitis through the regulation of adhesion molecule expression and neutrophil migration.
Leukotrienes play a part in inflammatory response. The unique role of the enzyme 5-lipoxygenase (5-LO) in the production of leukotrienes makes it as therapeutic target for inflammatory conditions like inflammatory bowel disease (IBD). In the present study, by comparing the responses in wild-type mice (5-LOWT) and mice lacking the 5-lipoxygenase (5-LOKO), we investigated the role played by this enzyme in the development of experimental colitis. To address this question, we used an experimental model of colitis, induced by dinitrobenzene sulfonic acid (DNBS). When compared to DNBS-treated 5-LOWT mice, DNBS-treated 5-LOKO mice experienced a reduced rate of the extent and severity of the histological signs of colon injury. After administration of DNBS 5-LOWT mice showed hemorrhagic diarrhea, weight loss and large areas of necrosis in the mucosa of the colon. Neutrophil infiltration was associated with the expression of ICAM-1, VCAM-1, P-selectin, E-selectin that were mainly localized around vessels. Absence of a functional 5-LO resulted in a significant reduction of all the above-described parameters. In particular, we have observed a significant reduction of: (i) the degree of colon injury, (ii) the rise in myeloperoxidase (MPO) activity (mucosa), (iii) the increase in staining (immunohistochemistry) for ICAM-1, VCAM-1, P-selectin, E-selectin caused by DNBS in the colon. Similarly, the treatment of 5-LOWT with zileuton (50 mg/kg per os twice a day) resulted in a significant reduction of all the above-described parameters. In addition, in in vitro study a significantly reduced chemotactic response to IL-8 was observed in peripheral blood leukocytes from 5-LOKO in comparison to 5-LOWT polymorphonuclear leukocyte. Similar results were obtained when we analyzed the chemotactic response of 5-LOWT cell incubated for 15 min with zileuton (50 microg/ml). Taken together, our results clearly demonstrate that 5-LO modulates neutrophil infiltration in experimental colitis through the expression of adhesion molecules. Topics: Animals; Arachidonate 5-Lipoxygenase; Chemotaxis, Leukocyte; Colitis; Diarrhea; Dinitrofluorobenzene; Gene Expression Regulation; Intercellular Adhesion Molecule-1; Mice; Mice, Knockout; Neutrophils; Peroxidase; Vascular Cell Adhesion Molecule-1 | 2005 |
Beneficial effects of N-acetylcysteine on acetic acid-induced colitis in rats.
Ulcerative colitis is a chronic recurrent inflammatory bowel disease in which oxidative stress has been implicated. The aim of the present study was to evaluate possible protective effects of N-acetylcysteine against acetic acid-induced colitis in a rat model. Rats were administered intrarectal saline (control group) or acetic acid (colitis model group). Rats with acetic acid-induced colitis were treated by intraperitoneal or intrarectal administration of N-acetylcysteine (500 mg/kg) (treated group). Another series of rats were pre-treated by intraperitoneal or intrarectal administration of N-acetylcysteine, then administered intrarectal acetic acid (pre-treated group). The degree of tissue injuries was assessed by macroscopical and histopathological scores of the colonic mucosa. Malondialdehyde, myeloperoxidase, reduced glutathione, superoxide dismutase, and catalase levels were measured in tissue extracts of the dissected colon. Administration of N-acetylcysteine intraperitoneally or intrarectally ameliorated macroscopic score alterations produced by acetic acid in treated groups. In addition, microscopical improvement was observed in all N-acetylcysteine-treated rats compared to untreated animals with colitis. In the colonic tissues of the acetic acid-induced colitis, myeloperoxidase activity and malondialdehyde levels were elevated, while the reduced glutathione levels and superoxide dismutase and catalase activities were decreased. However, intraperitoneal or intrarectal treatment with N-acetylcysteine reversed these parameters, compared to the untreated colitis group. Notably, intrarectal administration of N-acetylcysteine elevated the reduced glutathione levels more markedly compared to the other treatment groups. Superoxide dismutase levels were increased in intraperitoneally or intrarectally N-acetylcysteine-treated groups significantly compared to the control, colitis and pre-treated groups. But there was no significant increase in catalase activity. In conclusion, N-acetylcysteine could be beneficial as a complementary agent in treatment of ulcerative colitis. Topics: Acetic Acid; Acetylcysteine; Animals; Colitis; Glutathione; Lipid Peroxidation; Male; Peroxidase; Rats; Rats, Wistar | 2005 |
Thalidomide treatment reduces colon injury induced by experimental colitis.
The immunological and genetic pathogeneses of inflammatory bowel disease (IBD) have been well studied but not well elucidated in the recent years. Accordingly, the pharmacological treatment of IBDs is focusing upon the individual pathologic step (targeting therapy). It has been shown recently that new drugs such as biological immunomodulating agents and anti-inflammatory cytokines have better short-term effects in some respects than the conventional drugs, and they might change the treatment strategy of IBDs in the near future. The aim of the present study was to examine the effects of thalidomide treatment in the development of experimental colitis. To address this question, we used an experimental model of colitis, induced by dinitrobenzene sulfonic acid (DNBS). DNBS-treated mice experienced diarrhea and weight loss. At 4 days after administration of DNBS, the mucosa of the colon exhibited large areas of necrosis. The observed mucosa alteration was associated with the colon production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and vascular endothelial growth factor (VEGF). Neutrophil infiltration (determined by histology as well as an increase in myeloperoxidase activity in the mucosa) was associated with an upregulation of intercellular adhesion molecule-1. Immunohistochemistry for nitrotyrosine and poly (ADP ribose) showed an intense staining in the inflamed colon. When compared with DNBS-treated mice, thalidomide-treated (200 mg/kg orally) mice subjected to DNBS-induced colitis experienced a significantly lower rate in the extent and severity of the histological signs of colon injury. Thalidomide also caused a substantial reduction of the rise in myeloperoxidase activity (mucosa), in the increase in the tissue levels of TNF-alpha, IL-1beta, and VEGF, in the increase in staining (immunohistochemistry) for nitrotyrosine and for poly (ADP ribose), as well as in the upregulation of intercellular adhesion molecule-1 caused by DNBS in the colon. Thus, thalidomide treatment reduces the degree of colitis caused by DNBS. We propose that this evidence may help to clarify the therapeutic actions of thalidomide in patients with Crohn's disease. Topics: Animals; Colitis; Colon; Cytokines; Disease Models, Animal; Immunohistochemistry; Immunosuppressive Agents; Intercellular Adhesion Molecule-1; Interleukin-1; Mice; Neutrophils; Peroxidase; Poly Adenosine Diphosphate Ribose; Thalidomide; Time Factors; Tumor Necrosis Factor-alpha; Tyrosine; Vascular Endothelial Growth Factor A | 2005 |
The effect of angiotensin-converting enzyme inhibitors on experimental colitis in rats.
The present study was aimed to investigate the effect of ACE inhibition on trinitrobenzene sulphonic acid (TNBS)-induced colonic inflammation in rats by using captopril and lisinopril. In treatment groups, the rats were treated with ACE inhibitors, captopril or lisinopril (0.1 and 1 mg/kg/day; intraperitoneally). The drugs were given 5 min after induction of colitis and the treatment was continued for 3 days. Three days after the induction of colitis, all rats were decapitated. The distal colon was weighed and the mucosal lesions were scored at both macroscopical at microscopic levels. Malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were assessed in tissue samples. Formation of reactive oxygen species in colonic samples was monitored by using chemiluminescence technique. Serum TNF-alphalevel was assessed in trunk blood. Captopril treatment was found to be beneficial in all parameters, except colonic glutathione content. On the other hand, although stimulation of lipid peroxidation and increase in serum TNF-alpha level were successfully prevented by lisinopril, the morphology of the lesions remained unchanged. In conclusion, sulphydryl and non-sulphydryl ACE inhibitors, captopril and lisinopril do not seem to be similarly effective in TNBS-induced colitis model at least at the doses tested in our study. Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Captopril; Colitis; Collagen; Colon; Disease Models, Animal; Enzyme Inhibitors; Female; Glutathione; Lisinopril; Male; Malondialdehyde; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2005 |
Effects of acupuncture at GV01 on experimentally induced colitis in rats: possible involvement of the opioid system.
Oriental medicine uses acupuncture at the GV01 acupoint with great success to treat diarrhea. It significantly reduced the colonic motility and inflammation in colitic rats. Naloxone pretreatment blocked these effects. The therapeutic effects of acupuncture at GV01 in colitis may involve endogenous opioid pathways. Topics: Acupuncture Points; Acupuncture Therapy; Animals; Colitis; Colon; Disease Models, Animal; Gastrointestinal Motility; Injections, Subcutaneous; Male; Naloxone; Narcotic Antagonists; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2005 |
Amelioration of experimental colitis by Na-H exchanger-1 inhibitor amiloride is associated with reversal of IL-1ss and ERK mitogen-activated protein kinase.
Na-H exchanger-1 (NHE-1) is induced in experimental colitis. It has not yet been established whether its inhibition ameliorates colitis. The effects of amiloride, an inhibitor of NHE-1, on colitis were examined in this study. Levels of mitogen-activated protein (MAP) kinases ERK, p38 and interleukin 1ss which participate in intestinal inflammation were also examined in the colonic smooth muscle of rats with colitis.. Colitis was induced in Sprague-Dawley male rats by intrarectal administration of trinitrobenzenesulphonic acid (TNBS) and treated daily with amiloride (3, 5, and 10 mg/kg b.w. (body-weight), orally) starting 1 h before induction of colitis. The animals were sacrificed on day 5 post-TNBS. Controls received phosphate buffered saline in a similar manner.. The highest dose of amiloride (10 mg/kg) was lethal. The lowest dose (3 mg/kg) was tolerated and was used in this study. Amiloride significantly reversed the colitis-reduced contractility and induction of MPO activity, NHE-1, IL-1ss and ERK, but not of p38 in inflamed colonic smooth muscle. Splenomegaly, increased colonic mass and decreased sodium pump activity were significantly reversed by amiloride treatment. There was no recovery of b.w. loss in the treated colitic animals. Urine output was increased, whereas food and water intake remained unchanged following amiloride treatment.. These findings suggest that the beneficial effects of NHE-1 inhibition in experimental colitis are mediated through IL-1ss and ERK MAP kinase. Topics: Amiloride; Animals; Blotting, Western; Colitis; Diuretics; Extracellular Signal-Regulated MAP Kinases; Interleukin-1; Male; Muscle Contraction; Muscle, Smooth; p38 Mitogen-Activated Protein Kinases; Peroxidase; Rats; Rats, Sprague-Dawley; Sodium-Hydrogen Exchangers; Trinitrobenzenesulfonic Acid | 2005 |
Green tea polyphenol extract attenuates colon injury induced by experimental colitis.
Inflammatory bowel disease (IBD) is characterised by oxidative and nitrosative stress, leukocyte infiltration, and up-regulation of intercellular adhesion molecule 1 (ICAM-1) expression in the colon. The aim of the present study was to examine the effects of green tea extract in rats subjected to experimental colitis induced by intracolonic instillation of dinitrobenzene sulphonic acid (DNBS). At 4 days after DNBS administration the rats were sacrificed. Treatment with green tea extract significantly attenuated diarrhoea and loss of body weight. This was associated with a remarkable amelioration of the disruption of the colonic architecture, significant reduction of colonic myeloperoxidase (MPO) and tumor necrosis factor-alpha (TNF-alpha) production. Green tea extract also reduced the appearance of nitrotyrosine immunoreactivity in the colon and reduced the up-regulation of ICAM-1. Topics: Animals; Benzenesulfonates; Chromatography, High Pressure Liquid; Colitis; Colon; Flavonoids; Heme Oxygenase (Decyclizing); Immunohistochemistry; Intercellular Adhesion Molecule-1; Male; Peroxidase; Phenols; Phytotherapy; Plant Leaves; Polyphenols; Rats; Rats, Sprague-Dawley; Tea; Tumor Necrosis Factor-alpha; Tyrosine | 2005 |
Development of dextran sulfate sodium-induced colitis is aggravated in mice genetically deficient for complement C5.
The complement system is a potent effector of innate immunity. To elucidate the pathophysiological role of the complement system in inflammatory bowel disease (IBD), we evaluated the development of dextran sulfate sodium (DSS)-induced colitis in genetically complement C5-deficient mice. We used DBA2/J mice, which are genetically deficient in complement C5. DBA1/J mice have a normal complement system, and were used as controls. Experimental colitis was induced by the oral administration of 3.5% (w/v) DSS in their drinking water for 10 days. On day 10, all mice were sacrificed and their colons were collected. The development of colitis was assessed by the histological score, disease activity index, myeloperoxidase (MPO) activity, and macroscopic changes of the colon. Body weight loss was more apparent in the DBA2/J mice than in control DBA1/J mice. The colon length was shorter in the DBA2/J mice than in DBA1/J mice. The disease activity index, histological colitis score, and MPO activity were all significantly higher in the DBA2/J mice than in DBA1/J mice. Microscopically, mucosal edema, cellular infiltration and disruption of the epithelium were much more severe in the DBA2/J mice than in DBA1/J mice. The development of DSS colitis was aggravated in genetically C5-deficient DBA2/J mice. These findings suggest that the complement system might play a protective role in the development of DSS-induced experimental colitis. Topics: Animals; Body Weight; Colitis; Complement C5; Dextran Sulfate; Intestinal Mucosa; Mice; Mice, Inbred DBA; Mice, Knockout; Peroxidase; Time Factors | 2005 |
Effect of processed Scutellaria baicalensis on dextran sulfate sodium-induced colitis in mice.
Scutellaria baicalensis Georgi (Labiatae) has been used in the treatment of inflammatory diseases. Drug processing (Poje) is the process of treating crude drugs by several methods before use. The aim of this study was to determine the effect of processed Scutellaria baicalensis on experimental ulcerative colitis induced by dextran sulfate sodium (DSS). The types of processed Scutellaria baicalensis used in this study were parched Scutellaria baicalensis (PS) and rice wine-baked Scutellaria baicalensis (RWBS). Experimental colitis was induced in mice using a daily treatment of 5% DSS in the drinking water for 7 days. The water extracts of processed Scutellaria baicalensis (1 g/kg) were administered orally once a day for 7 days. The mice were divided in four groups: i) water plus DSS group, ii) crude Scutellaria baicalensis (CS) plus DSS group, iii) PS plus DSS group, and iv) RWBS plus DSS group. RWBS ameliorated all of the inflammatory symptoms, such as body weight loss, rectal bleeding and histological damage, compared to CS. Furthermore, RWBS significantly reduced the mucosal myeloperoxidase activity, and TNF-alpha (tumor necrosis factor-alpha), COX-2 (cyclooxygenase-2), NF-kappaB (nuclear factor-kappa B) and chymase expression more than CS. But these effects were not shown in the PS plus DSS group. Efficacy of Scutellaria baicalensis was increased after rice wine baking, but not after parching. The findings in this study suggest that RWBS may be a useful therapeutic agent for ulcerative colitis. Topics: Animals; Blotting, Western; Colitis; Colon; Dextran Sulfate; Female; Mice; Mice, Inbred BALB C; NF-kappa B; Peroxidase; Phytotherapy; Plant Extracts; Plant Roots; Scutellaria baicalensis; Water; Wine | 2005 |
Change of nitric oxide in experimental colitis and its inhibition by melatonin in vivo and in vitro.
To investigate the change of nitric oxide (NO) in rat colitis and its inhibition by melatonin in vivo and in vitro.. In vivo, rat colitis was established intracolonically with trinitrobenzenesulphonic acid (TNBS) and ethanol. The animals were randomised into five groups: control group, model group, melatonin group (2.5, 5.0, 10.0 mg/kg), and treated intracolonically with saline, saline and melatonin respectively (once a day, from day 7 after colitis was established to day 28). After the end of the experiment, the mucosal damage index (CMDI) and histology score (HS) were evaluated and the level of myeloperoxidase (MPO) and malondiadehyde (MDA) and NO in the colon tissue were measured. In vitro, the co-culture model of the inflamed colon mucosa (from the colitis) with lipopolysaccharide (LPS), and the colonocytes oxidative injury model by hydroxyl radical, were designed respectively to elucidate the inhibition of NO by melatonin.. After treated with TNBS/ethanol, the extent of CMDI and HS, the levels of MPO, MDA, and NO in the model group, were higher than that in the control group; melatonin ameliorated these parameters effectively. The stimulation of LPS increased the level of NO and MPO and MDA in the co-culture model of inflamed colon mucosa, and melatonin significantly reduced the level of MPO, MDA, and NO. In the coloncyte oxidative injury model by hydroxyl radical, the contents of LDH, MDA, and NO were increased; melatonin reversed this oxidative injury considerably.. This study showed that TNBS/ethanol induced colitis was pharmacologically controlled by melatonin in vivo and in vitro. Topics: Animals; Colitis; Free Radical Scavengers; Hydroxyl Radical; In Vitro Techniques; Male; Malondialdehyde; Melatonin; Nitric Oxide; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 2005 |
Inhibitory effects of histamine H4 receptor antagonists on experimental colitis in the rat.
The histamine H(4) receptor is a G-protein coupled receptor with little homology to the pro-inflammatory histamine H(1) receptor, expressed on cells of the immune system with hematopoietic lineage such as eosinophils and mast cells. The effects of the recently described highly selective histamine H(4) receptor antagonists JNJ 10191584 and JNJ 7777120 have now been investigated on the acute colitis provoked by trinitrobenzene sulphonic acid over 3 days in the rat. Treatment with JNJ 10191584 (10-100 mg/kg p.o., b.i.d.) caused a dose-dependent reduction in macroscopic damage, inhibition of the TNBS-provoked elevation of both colonic myeloperoxidase and tumour necrosis factor-alpha (TNF-alpha), and a reduction in the histologically assessed increase in mucosal and submucosal thickness and neutrophil infiltration. JNJ 7777120 (100 mg/kg p.o., b.i.d.) likewise reduced the macroscopic injury and the increases in colonic myeloperoxidase and TNF-alpha levels. These findings indicate a pro-inflammatory role for the histamine H(4) receptor in this model and suggest a novel pharmacological approach to the treatment of colitis. Topics: Acute Disease; Animals; Benzimidazoles; Body Weight; Colitis; Colon; Dose-Response Relationship, Drug; Indoles; Male; Organ Size; Peroxidase; Piperazines; Rats; Rats, Wistar; Receptors, G-Protein-Coupled; Receptors, Histamine; Receptors, Histamine H4; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2005 |
Short-term treatment with anti-CD44v7 antibody, but not CD44v4, restores the gut mucosa in established chronic dextran sulphate sodium (DSS)-induced colitis in mice.
Increased expression of CD44 variant isoforms have been shown on the inflammatory infiltrates in human and mouse colitis and blockade or deletion of CD44 isoforms inhibit experimental colitis. The objective of this study was to find out if short-term treatment of CD44 antibodies specific to CD44v7, but not to other variant isoforms, suppresses leucocyte-endothelial interaction in chronic dextran sodium sulphate (DSS)-induced colitis in mice. Chronic colitis was induced by oral administration of four cycles of 5% DSS in BALB/c mice. Expression of CD44 was investigated on isolated mononuclear cells of the gut immune system. In established colitis, mice were treated with antibodies against CD44v7 or CD44v4 three times in 7 days. Intravital microscopy was used to study leucocyte-endothelial interactions and leucocyte extravasation. As a marker of inflammatory infiltrates myeloperoxidase was quantified in gut tissue. CD44-induced apoptosis was determined by fluorescence staining of hypodiploidic cell nuclei. In chronic DSS-induced colitis both CD44 variant isoforms, v4 and v7 were significantly up-regulated on mononuclear cells. However, whereas anti-CD44v7 antibody treatment induced a marked restoration of the gut mucosa and significantly reduced endothelial sticking and extravasation of circulating leucocyte in vivo (P < 0.01), application of anti-CD44v4 or an isotype control antibody had no anti-inflammatory effect. A significant reduction of myeloperoxidase activity was detected after blockade of CD44v7, but not v4. Short-term treatment with anti-CD44v7 antibody blocks T cell extravasation and recruitment to the intestinal mucosa and cures established experimental colitis. Topics: Animals; Antibodies, Monoclonal; Cell Adhesion; Chronic Disease; Colitis; Dextran Sulfate; Disease Models, Animal; Down-Regulation; Endothelial Cells; Female; Hyaluronan Receptors; Immunity, Mucosal; Intestinal Mucosa; Leukocytes; Lymph Nodes; Lymphocyte Activation; Mesentery; Mice; Mice, Inbred BALB C; Peroxidase; Protein Isoforms | 2005 |
Amelioration of experimental colitis by Astragalus membranaceus through anti-oxidation and inhibition of adhesion molecule synthesis.
To investigate the protective effects of Astragalus membranaceus (Am) against hapten-induced colitis in male Sprague-Dawley rats as well as its underlying mechanism.. Experimental colitis was induced in rats by enema administration of 2,4-dinitrobenzene sulfonic acid (DNBS). Rats were either pretreated with Am extract (2 or 4 g/kg, p.o. once daily) starting from 10 d before DNBS enema, or received Am post-treatment (2 or 4 g/kg, p.o. twice daily) on the three consecutive days following DNBS administration. Colonic lesion area and histological damage were determined, while the activities of myeloperoxidase (MPO) and xanthine oxidase, as well as reduced glutathione (GSH) content were measured in the excised colonic tissues. Besides, protein expression of inducible nitrite oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1) and P-selectin was also detected by Western blot analysis.. Our findings had shown that both macroscopic lesion area and histological colonic damage induced by DNBS were significantly reduced by both Am pre- and post-treatments. These were accompanied by attenuation of the elevated colonic MPO activity and downregulation of the iNOS, P-selectin, and ICAM-1 protein expression. Besides, deprivation of colonic GSH level under colitis condition was also preserved.. These results demonstrate that Am possesses both preventive and therapeutic potential in experimental colitis. The anti-inflammatory actions involve anti-oxidation along with inhibition of adhesion molecule synthesis in the colonic tissues. Topics: Animals; Astragalus propinquus; Colitis; Colon; Dinitrofluorobenzene; Glutathione; Humans; Inflammatory Bowel Diseases; Intercellular Adhesion Molecule-1; Male; Medicine, Chinese Traditional; Nitric Oxide Synthase Type II; Oxidation-Reduction; P-Selectin; Peroxidase; Phytotherapy; Plant Extracts; Rats; Rats, Sprague-Dawley; Xanthine Oxidase | 2005 |
Polaprezinc (N-(3-aminopropionyl)-L-histidinato zinc) ameliorates dextran sulfate sodium-induced colitis in mice.
Polaprezinc (N-(3-Aminopropionyl)-L-histidinato zinc), an anti-ulcer drug, has been reported to have an anti-inflammatory action in several inflammatory diseases. The aim of this study was to investigate the effect of polaprezinc on dextran sulfate (DSS)-induced colitis in mice.. Mice with colitis induced by DSS were intrarectally treated with polaprezinc (15 mg/kg) or zinc sulfate (7.5 mg/kg) every day after the administration of DSS for 7 days. Disease activity index (DAI) and histological tissue damage were assessed. Levels of myeloperoxidase (MPO) activity, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma in the colon were measured. Expression of heat shock protein (HSP) 25 and HSP70 in the colon was analyzed by Western blot analysis.. DAI and histological scores were remarkably reduced in polaprezinc-treated mice with DSS-induced colitis. Polaprezinc suppressed the increase of MPO activity and the production of TNF-alpha and IFN-gamma in the colon tissues of mice with DSS-induced colitis. Expression of HSP25 and HSP70 was remarkably up-regulated in the colon tissues of polaprezinc-treated mice during DSS treatment.. Polaprezinc suppresses DSS-induced colitis in mice, partly through inhibition of production of pro-inflammatory cytokine, suppression of neutrophils accumulation and cytoprotection by overexpression of HSPs. Polaprezinc could be useful in the treatment of inflammatory bowel diseases. Topics: Analysis of Variance; Animals; Anti-Ulcer Agents; Biopsy, Needle; Carnosine; Colitis; Cytokines; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Heat-Shock Proteins; Immunohistochemistry; Intestinal Mucosa; Male; Mice; Mice, Inbred C57BL; Organometallic Compounds; Peroxidase; Probability; Random Allocation; Reference Values; Sensitivity and Specificity; Zinc Compounds | 2005 |
The role of PKCdelta and PKCepsilon in the neonatal rat colon in response to hypoxia challenge.
Previous studies have determined that, in response to bacterial endotoxin, the colonic mucosa of the 10-d-old neonatal rat was more susceptible to injury than was the colon of the 25-d-old mature animal. Furthermore, it is known that certain isoforms of protein kinase C (PKC), specifically PKCdelta and PKCepsilon, mediate intestinal inflammatory responses to specific challenges. Therefore, in the present study, we have examined the association between the activation of these PKC isoforms and the enhanced susceptibility to hypoxia-induced challenge. In response to exposure to a hypoxic environment (14% O2/86% N2, 30 min), the degree of inflammation and tissue damage was significantly greater in 10- than in 25-d-old rats. The injury in 10-d-old rats was associated with activation of PKCdelta and PKCepsilon as estimated by translocation of the isoform from cytosolic to membrane fraction of the tissue lysate. There was no activation of either isoform in colons from 25-d-old rats after hypoxia. Pretreatment of 10-d-old rats with epidermal growth factor (EGF) (10 microg/kg) but not 16,16 dimethyl prostaglandin E2 (2 microg/kg) significantly reduced the extent of colonic injury, whereas neither agent was able to exert significant protection of the colonic mucosa of 25-d-old rats. PKC activation associated with hypoxia was not evident after EGF treatment in 10-d-old rats. In 25-d-old rats, prostaglandin E2 treatment was linked with an activation of PKCepsilon only. In conclusion, these data suggest that activation of PKCdelta and PKCepsilon is associated with the enhanced susceptibility to injury evident in suckling neonatal rat colon. EGF-mediated protection of the colon in these animals results in a removal of this PKC activation. Topics: Animals; Animals, Newborn; Colitis; Colon; Female; Gene Expression Regulation, Enzymologic; Hypoxia; Male; Peroxidase; Protein Kinase C; Protein Kinase C-delta; Protein Kinase C-epsilon; Rats; Rats, Sprague-Dawley; RNA, Messenger | 2004 |
Paradoxical roles of different nitric oxide synthase isoforms in colonic injury.
Nitric oxide (NO) is a free radical that is largely produced by three isoforms of NO synthase (NOS): neuronal (nNOS), endothelial (eNOS), and inducible (iNOS). NO regulates numerous processes in the gastrointestinal tract; however, the overall role that NO plays in intestinal inflammation is unclear. NO is upregulated in both ulcerative colitis and Crohn's disease as well as in animal models of colitis. There have been conflicting reports on whether NO protects or exacerbates injury in colitis or is simply a marker of inflammation. To determine whether the site, timing, and level of NO production modulate the effect on the inflammatory responses, the dextran sodium sulfate model of colitis was assessed in murine lines rendered deficient in iNOS, nNOS, eNOS, or e/nNOS by targeted gene disruption. The loss of nNOS resulted in more severe disease and increased mortality, whereas the loss of eNOS or iNOS was protective. Furthermore, concomitant loss of eNOS reversed the susceptibility found in nNOS-/- mice. Deficiencies in specific NOS isoforms led to distinctive alterations of inflammatory responses, including changes in leukocyte recruitment and alterations in colonic lymphocyte populations. The present studies indicate that NO produced by individual NOS isoforms plays different roles in modulating an inflammatory process. Topics: Animals; Colitis; Female; Flow Cytometry; Immunohistochemistry; Intestinal Mucosa; Isoenzymes; Leukocyte Count; Leukocytes; Male; Mice; Mice, Inbred C57BL; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type I; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Peroxidase; Reverse Transcriptase Polymerase Chain Reaction; RNA | 2004 |
Concurrent infection with Schistosoma mansoni attenuates inflammation induced changes in colonic morphology, cytokine levels, and smooth muscle contractility of trinitrobenzene sulphonic acid induced colitis in rats.
Crohn's disease, characterised by chronic T helper 1 (Th1) inflammation and dysmotility of the gut, is most prevalent in developed countries. Parasitic infections are most prevalent in developing countries and induce a T helper 2 (Th2) immune response. We hypothesised that this Th2 immune response protects against Th1 gut inflammation.. The parasite Schistosoma mansoni induces a transient Th2 immune response in the semipermissive rat host. 2,4,6-Trinitrobenzene sulphonic acid (TNBS) induced colitis is an experimental model of Th1-like gut inflammation. The effect of concurrent infection with S mansoni on the course of TNBS induced colitis was assessed using macroscopic and microscopic damage scores, histology, myeloperoxidase (MPO) activity assay, cytokine production assay, and by studying in vitro contractility of longitudinal and circular colonic muscle strips.. TNBS induced colitis that spontaneously healed after four weeks. Concurrent infection with S mansoni significantly reduced the duration of TNBS induced colitis to two weeks, as shown by macroscopic and microscopic damage scores and by a faster decrease in colonic MPO activity. TNBS increased colonic interleukin 2 (IL-2) production whereas S mansoni increased splenic IL-4 and IL-2 levels. Contractility of longitudinal and circular muscle strips was maximally inhibited one week after TNBS and normalised after three weeks. After four weeks, longitudinal muscle strip contractility was significantly increased. Concurrent infection with S mansoni normalised longitudinal muscle contractility after one week whereas circular muscle contractility remained inhibited.. Concurrent infection with S mansoni significantly attenuates TNBS induced colitis in the rat. Inflammation induced disturbances in contractility of longitudinal and circular colonic muscle strips may outlast the inflammatory reaction. Topics: Animals; Colitis; Colon; Crohn Disease; Cytokines; Disease Models, Animal; Intestinal Mucosa; Male; Muscle Contraction; Muscle, Smooth; Peroxidase; Rats; Rats, Wistar; Schistosomiasis mansoni; Spleen; Th1 Cells; Th2 Cells; Trinitrobenzenesulfonic Acid | 2004 |
The anti-inflammatory effect of leptin on experimental colitis: involvement of endogenous glucocorticoids.
The present study was designed to compare the effect of leptin on acute colonic inflammation with that of acute stress exposure, which acts via the hypothalamic-pituitary-adrenal (HPA) axis. Sprague-Dawley rats of both sexes were administered intrarectally with acetic acid. Either leptin (10 microg/kg; i.p.) or saline was injected immediately before and 6 h after the induction of colitis. A group of rats was exposed to water avoidance stress (WAS) for 30 min at the 6th h of colitis induction. RU-486 (2 mg/kg; i.p.), a glucocorticoid receptor antagonist, was injected intraperitoneally, at 12 and 1 h before the initial leptin injection, and at 1 h before the second leptin injection or exposure to WAS. Rats were decapitated at 24 h and the distal 8 cm of the colon were removed for macroscopic and microscopic scoring, determination of tissue wet weight index (WI) and tissue myeloperoxidase activity (MPO). Acetic acid-induced colitis significantly increased macroscopic and microscopic damage scores, WI and MPO, compared to control group. Exposure to acute WAS or treatment with leptin reduced the elevations in damage scores, WI and MPO induced by colitis, but no additive inhibitory effect was observed when WAS and leptin were applied together. RU-486 treatment reversed the inhibitory effects of leptin or WAS on colonic inflammation. Our results demonstrate that exogenous leptin mimics the effects of HPA axis activation on colitis-induced inflammatory process. The results also suggest that the anti-inflammatory effect of leptin involves a tissue neutrophil-dependent mechanism and is dependent on the release of glucocorticoids. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Colitis; Colon; Dehydration; Female; Glucocorticoids; Inflammation; Leptin; Male; Peroxidase; Rats; Rats, Sprague-Dawley | 2004 |
Neonatal maternal deprivation triggers long term alterations in colonic epithelial barrier and mucosal immunity in rats.
Stressful events in the early period of life (for example, maternal deprivation) have been shown to modify adult immune and gastrointestinal tract functions. The present study aimed to establish whether maternal deprivation affects colonic epithelial barrier and the development of an experimental colitis in adult rats.. Male Wistar rat pups were separated during postnatal days 2-14 or left undisturbed with their dam. At 12 weeks of age, we assessed colonic paracellular permeability, bacterial translocation, myeloperoxidase (MPO) activity, mucosal mast cell density, cytokine (interleukin (IL)-1 beta, IL-2, IL-4, IL-10, and interferon gamma (IFN-gamma)) mRNA expression, and macroscopic damage. Total gut permeability, MPO activity, and macroscopic damage were also assessed four days after intracolonic administration of 2,4,6-trinitrobenzenesulphonic acid (TNBS).. Maternal deprivation triggered a significant increase in colonic permeability associated with bacterial translocation into the mesenteric lymph nodes, liver, and spleen. These alterations were associated with some macroscopic damage and an increase in colonic MPO activity, mucosal mast cell density, and cytokine mRNA expression. Intracolonic infusion of TNBS induced a significantly higher inflammatory reaction in separated animals, as judged by enhanced MPO colonic levels, total gut permeability, and macroscopic lesions.. Maternal deprivation promotes long term alterations in the colonic epithelial barrier associated with an exaggerated immune response to an external immune stimulus. This suggests a role for early psychological factors in the regulation of colonic mucosal barrier in later life. Topics: Animals; Animals, Newborn; Bacterial Translocation; Colitis; Colon; Cytokines; Disease Susceptibility; Female; Immunity, Mucosal; Intestinal Mucosa; Male; Mast Cells; Maternal Deprivation; Permeability; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2004 |
1,8-cineole (eucalyptol), a monoterpene oxide attenuates the colonic damage in rats on acute TNBS-colitis.
The monoterpene oxide, 1,8-cineole (cineole, eucalyptol) was examined for its possible influence on the acute phase of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. The test compound, 1,8-cineole (200 and 400 mg/kg) or vehicle (1 ml, 2% Tween 80) was instilled rectally, 24, and 2 h before (pre-treatment) or 2 and 24 h after (post-treatment) the induction of colitis by intracolonic administration of TNBS (0.25 ml of 25 mg of TNBS in 50% ethanol). Rats were killed 48 h after colitis induction and colonic segments were analysed for gross damage scores, changes in wet weights, myeloperoxidase activity, an indicator of neutrophilic infiltration and glutathione level, a major cellular antioxidant. TNBS induced an extensive inflammation and ulceration in the colon. Colonic damage was associated with an increase in myeloperoxidase activity and by a decrease in glutathione. When compared to vehicle-treated TNBS controls, a marked reduction in gross damage scores and wet weights (mg/cm) of colonic segments were evident in animals pre-treated but not post-treated with 1,8-cineole. Cineole also significantly reduced the myeloperoxidase activity, and caused repletion of glutathione. These results confirm the anti-inflammatory action of 1,8-cineole and suggest its potential value as a dietary flavoring agent in the prevention of gastrointestinal inflammation and ulceration. Topics: Acute Disease; Administration, Rectal; Animals; Anti-Inflammatory Agents; Colitis; Colon; Cyclohexanols; Disease Models, Animal; Dose-Response Relationship, Drug; Eucalyptol; Glutathione; Instillation, Drug; Intestinal Mucosa; Male; Monoterpenes; Organ Size; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2004 |
A protective effect of the synthetic coumarine derivative Cloricromene against DNB-colitis in the rat.
Biologic therapies, namely antibodies against tumor necrosis factor-alpha (TNF- alpha) or its receptors, have been recently introduced for the treatment of patients with inflammatory bowel disease (IBD). In the present study the effects of cloricromene, an agent with known antithrombotic actions and with demonstrated anti-TNF- alpha activity were investigated in a rat model of experimental colitis induced with dinitrobenzenesulphonic acid (DNB)/ethanol. We investigated three experimental groups: (i) sham-colitis with vehicle-treatment (controls, n = 6), (ii) colitis with vehicle-treatment (saline, 0.1 ml s.c., daily) (DNB-V, n = 7), (iii) colitis with cloricromene-treatment (10 mg/kg/day s.c.; DNB-C, n = 8). After 7 days, the weight gain, colon wet weight, macroscopic damage score, coagulation parameters, colon mucosal myeloperoxidase activity (MPO), and tissue concentrations of TNF- alpha and of macrophage inhibitory peptide-2 (MIP-2) were assessed. The macroscopic damage scores, colon wet weights, and tissue MIP-2 levels were significantly increased in untreated and in cloricromene-treated rats compared with controls. Cloricromene treatment was associated with a minor body weight loss (p < 0.025) and significantly reduced tissue concentrations of MPO and TNF-alpha (p < 0.02, both). Blood coagulation parameters were not affected by treatment. In the DNB-model treatment with cloricromene effectively reduces tissue levels of TNF- alpha and of myeloperoxidase, whereas MIP-2 concentrations were not influenced. Blood coagulation parameters remained unchanged indicating safety of treatment. Since biological therapies frequently fail to improve disease course of IBD, other therapies with similar targets should be further investigated. Topics: Animals; Benzenesulfonates; Body Weight; Chemokine CXCL2; Chromonar; Colitis; Colon; Injections, Subcutaneous; Intestinal Mucosa; Male; Monokines; Organ Size; Peroxidase; Platelet Aggregation Inhibitors; Rats; Rats, Sprague-Dawley; Treatment Outcome; Tumor Necrosis Factor-alpha | 2004 |
Effects of feeding a probiotic preparation (SIM) containing inulin on the severity of colitis and on the composition of the intestinal microflora in HLA-B27 transgenic rats.
An overly aggressive immune response to the intestinal microflora in a genetically susceptible host background has been implicated in the pathogenesis of inflammatory bowel diseases. We measured the impact of a probiotic preparation (SIM) containing inulin on the severity of colitis and on intestinal microflora profiles of HLA-B27-beta(2)-microglobulin transgenic (TG) rats. SIM is a mixture of lactobacilli, bifidobacteria, and inulin. Two-month-old TG rats received either SIM or water. Control TG rats received metronidazole, alone or in combination with SIM, for 8 weeks. Nontransgenic rats received SIM or water. The cecal content was removed for analysis of the intestinal microflora by PCR combined with denaturing gradient gel electrophoresis. The colon was scored for histological evidence of inflammation, colonic myeloperoxidase activity and interleukin-1beta RNA levels were measured photometrically or by real-time quantitative PCR. At 4 months, the colonic inflammation of TG rats treated with SIM was histologically diminished compared to that in untreated TG rats (2.2 +/- 0.2 versus 2.9 +/- 0.1; P = 0.03). The administration of SIM altered the microflora profiles of TG rats by increasing the diversity and stimulating specifically the growth of Bifidobacterium animalis. The probiotic bacteria added to SIM were below the detection level in cecal stool samples at the end of the study period. The administration of SIM resulted in a measurable impact on the cecal microflora profiles of TG rats with attenuation of colitis. The lack of detection of any added probiotic bacteria in the cecal content suggests that prebiotic inulin is the major effective compound. Topics: Animals; Animals, Genetically Modified; Bacteria; beta 2-Microglobulin; Bifidobacterium; Colitis; Colon; DNA, Bacterial; Electrophoresis, Polyacrylamide Gel; HLA-B27 Antigen; Inflammatory Bowel Diseases; Intestines; Inulin; Lactobacillus; Lactobacillus acidophilus; Metronidazole; Peroxidase; Polymerase Chain Reaction; Probiotics; Rats; Rats, Inbred F344; Sequence Analysis, DNA | 2004 |
Synergistic effects of systemic trefoil factor family 1 (TFF1) peptide and epidermal growth factor in a rat model of colitis.
Novel therapies for the treatment of colitis are required. We therefore examined the potential value of the trefoil factor family 1 (TFF1) peptide and epidermal growth factor (EGF) alone and in combination. Effects of TFF1- Cys58 +/- EGF on an in vitro HT29 cell wounding model of restitution showed synergistic activity when used in combination. In addition, animals had colitis induced by adding 4% dextran sulphate sodium (DSS) to the drinking water for 7 days and they also received twice daily subcutaneous injections of test peptides. Treatment with TFF1-Cys58 alone (100 microg/kg) reduced histological colitis score by 22%, but the TFF1-Ser58 variant was ineffective. In a second study, TFF1-Cys58 reduced histological colitis score by 15%, EGF (600 microg/kg) by 26%, and an additive response (42% reduction) was demonstrated when used together (P < 0.01 versus either peptide given alone). Similar results were found using tissue myeloperoxidase (MPO) activity as a marker of inflammation. Where clinical risk/benefit seems justified, these initial studies suggest that combination therapy of systemic EGF and TFF peptides may prove useful for treatment of colitis in patients with disease extending beyond the reach of topical (enema) therapy. Topics: Animals; Colitis; Colon; Dextran Sulfate; Drug Synergism; Epidermal Growth Factor; HT29 Cells; Humans; Lipopolysaccharides; Male; Mucins; Muscle Proteins; Peptides; Peroxidase; Proteins; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Trefoil Factor-1; Trefoil Factor-2; Tumor Suppressor Proteins; Wound Healing | 2004 |
Inhibition of glycolipid biosynthesis by N-(5-adamantane-1-yl-methoxy-pentyl)-deoxynojirimycin protects against the inflammatory response in hapten-induced colitis.
Since glycolipid biosynthesis is potentially involved in immunological and inflammatory responses, we tested the effect of a novel inhibitor of intracellular glycolipid biosynthesis N-(5-adamantane-1-yl-methoxy-pentyl)-deoxynojirimycin (AMP-DNM) in two hapten-induced colitis models: trinitrobenzene sulphonic acid (TNBS)- and oxazolone (4-ethoxymethylene-2phenyl-2oxazoline-5-one; Oxa)-induced colitis. AMP-DNM was given either by intraperitoneal injection or orally via the diet. Mice treated with AMP-DNM had less severe colitis and a more rapid weight recovery, less edema and less wall thickness. Cellular infiltration, goblet cell loss and myeloperoxidase (MPO) activity were reduced in colons of AMP-DNM-treated animals. Intralesional IFN-gamma and IL-18 production were lower in mice of the AMP-DNM-treated groups. Furthermore, AMP-DNM treatment reduced the serum anti-TNBS and anti-Oxa antibody levels. Our findings show that the glycolipid biosynthesis inhibitor AMP-DNM has a strong anti-inflammatory and immune suppressive activity on both TNBS- and Oxa-induced colitis. The data also provide evidence that glycolipid biosynthesis is involved in the inflammatory cascade in these inflammatory bowel disease (IBD) models. Topics: 1-Deoxynojirimycin; Adamantane; Animals; Anti-Inflammatory Agents; Antibodies; Body Weight; Colitis; Colon; Disease Models, Animal; Enzyme Inhibitors; Glycolipids; Haptens; Immunoglobulin G; Immunosuppressive Agents; Interferon-gamma; Interleukin-18; Male; Mice; Mice, Inbred C57BL; Oxazolone; Peroxidase; Trinitrobenzenesulfonic Acid | 2004 |
Superoxide dismutase ameliorates TNBS-induced colitis by reducing oxidative stress, adhesion molecule expression, and leukocyte recruitment into the inflamed intestine.
Oxidant stress has been implicated in the pathogenesis of inflammatory bowel disease. Antioxidant enzymes, such as superoxide dismutase (SOD), are candidate drugs for modulating this pathogenic factor. This study was designed to determine the therapeutic value of SOD in an experimental model of colitis and to study the mechanisms underlying its effects on intestinal inflammation. For that purpose, colitic (trinitrobenzene sulfonic acid-induced) and control rats were studied. Groups of colitic animals were treated with different doses of SOD (1, 4, or 13 mg/kg/day) or vehicle, starting after induction of colitis and during 7 days. Clinical and pathological markers of colitis severity and lipid peroxidation in colonic tissue were measured. Leukocyte-endothelial cell interactions in colonic venules and expression of vascular cell adhesion molecule 1 (VCAM-1) were determined. Development of colitis was associated with a significant loss in body weight, an increase in macroscopic and microscopic damage scores, and colonic myeloperoxidase activity. Administration of SOD significantly attenuated these changes in a dose-dependent manner and reduced lipid peroxidation in colonic tissue. The increase in leukocyte rolling and adhesion in colonic venules of colitic rats were significantly reduced by administration of SOD, 13 mg/kg/day. Development of colitis was associated with a marked increase in endothelial VCAM-1 expression, which was significantly reduced by treatment with SOD. In conclusion, treatment with SOD significantly reduces peroxidation reactions in the inflamed colon and affords significant amelioration of colonic inflammatory changes in experimental colitis. This effect is related to a reduction in VCAM-1 expression and leukocyte recruitment into the inflamed intestine. Topics: Animals; Body Weight; Cell Adhesion; Cell Adhesion Molecules; Chemotaxis, Leukocyte; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Down-Regulation; Intestinal Mucosa; Lipid Peroxidation; Male; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; Trinitrobenzenesulfonic Acid; Vascular Cell Adhesion Molecule-1; Venules | 2004 |
Ameliorating effects of the immunomodulator 3-(2-ethylphenyl)-5-(3-methoxyphenyl)-1H-1,2,4-triazole in an experimental model of colitis in the rat.
The therapeutic efficacy of the immunomodulator 3-(2-ethylphenyl)-5-(3-methoxyphenyl)-1H-1,2,4-triazole (ST1959) in colonic inflammation was assessed in rats. One hour following colonic instillation of ethanolic 2,4,6-trinitrobenzene sulphonic acid (TNBS), intracolonic administration of 0.4 mg/kg ST1959 was started and continued once daily for 1 or 2 weeks. Daily administration of ST1959 for 1 week significantly reduced macroscopic and histological damage, myeloperoxidase activity, and colonic tissue levels of tumour necrosis factor-alpha and interferon-gamma. ST1959 did not affect interleukin-12 levels but significantly enhanced the production of interleukin-10 (sixfold increase). Two weeks of ST1959 treatment reduced the thickness of the colonic wall and myeloperoxidase activity to the same extent, and the histologic appearance of the mucosa was largely restored. The ameliorating effects seem to be ascribable to an impairment of both neutrophil infiltration/activation and tumour necrosis factor-alpha and interferon-gamma production, possibly consequent to the observed increase in the colonic tissue levels of the potent anti-inflammatory cytokine interleukin-10. Similar results were observed with the reference drug 5-aminosalycilic acid. Topics: Animals; Body Weight; Colitis; Colon; Cytokines; Diarrhea; Immunohistochemistry; Immunosuppressive Agents; Male; Neutrophil Infiltration; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Triazoles; Trinitrobenzenesulfonic Acid | 2004 |
5-ASA and lycopene decrease the oxidative stress and inflammation induced by iron in rats with colitis.
Supplementation of 5-aminosalicylic acid (5-ASA) and of iron are among the principal therapies in patients with inflammatory bowel disease. Therapeutic iron, as well as heme iron from chronic mucosal bleeding, can increase iron-mediated oxidative stress in colitis. This study was designed to examine the influence of iron supplementation on histological expression and oxidative status relative to 5-ASA treatment and antioxidant treatment.. Colitis was induced using the iodoacetamide rat model, and rats were divided into different dietary groups of 6 rats each: 1, normal chow diet (control); 2, diet supplemented with iron; 3, iron supplementation and lycopene; 4, iron and Beta-carotene; 5, 5-ASA; 6, 5-ASA and lycopene; 7, 5-ASA and iron; 8, 5-ASA, iron, and lycopene. The animals were killed after 3 days and the weight of the ulcerated area recorded. Mucosal specimens were histologically evaluated. Myeloperoxidase (MPO) was measured to evaluate inflammatory status (U/g). Malondialdehyde (MDA) was measured in colonic tissue ( micro mol/g) and superoxide dismutase (SOD) in erythrocytes to assess the degree of tissue oxidative stress.. Significantly more severe colitis, including necrosis, ulceration, and hemorrhage, was seen in colonic biopsies of rats with colitis when iron was supplemented. This pathology was attenuated when iron was given in combination with 5-ASA and/or lycopene. There was no significant benefit from adding Beta-carotene.. Iron supplementation can amplify the inflammatory response and subsequent mucosal damage in a rat model of colitis. We suggest that the resultant oxidative stress generated by iron supplementation leads to the extension and propagation of crypt abscesses, either through direct membrane disruption by lipid peroxidation or through the generation of secondary toxic oxidants. Simultaneous treatment with 5-ASA and/or lycopene minimizes the potential hazard of iron. Therefore, we suggest giving iron supplementation with 5-ASA or lycopene or both. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; beta Carotene; Carotenoids; Colitis; Disease Models, Animal; Iron; Lipid Peroxidation; Lycopene; Male; Mesalamine; Oxidative Stress; Peroxidase; Rats; Rats, Wistar | 2004 |
Blood flow alterations in TNBS-induced colitis: role of endothelin receptors.
The aim of the present study was to investigate the time dependent changes in hemodynamic parameters and to assess the role of endothelin (ET) receptors in trinitrobenzene sulfonic acid (TNBS) induced colitis.. Inferior mesenteric artery (IMA) hemodynamics, myeloperoxidase activity (MPO) and damage scores were measured immediately or 1, 3, 5 and 14 days after colitis.. Another group of rats received a nonselective ET receptor antagonist bosentan (30 mg/kg/day), ET-A receptor antagonist BQ485 (60 microg/rat/day) or ET-B receptor antagonist BQ788 (60 microg/rat/day) prior to and on the 1st, 2nd and 3rd days after TNBS administration.. IMA flow significantly increased at 90 min followed by a substantial decrease through days 1-5. Tissue MPO activity and macroscopic damage score increased on 1st day after the induction of colitis and remained elevated 3, 5 and 14 days following colitis. Treatment with bosentan or ET-A receptor antagonist largely prevented the colitis-induced reduction in blood flow and tissue injury whereas ET-B receptor antagonist did not attenuate tissue injury or reductions in blood flow.. Our results demonstrate that time-dependent abnormalities occur in IMA hemodynamics following TNBS administration. Our findings also indicate that ET-A receptors but not ET-B receptors play an important role in the colonic inflammation following TNBS administration. Topics: Animals; Antihypertensive Agents; Azepines; Bosentan; Colitis; Inflammation; Male; Mesenteric Arteries; Mucous Membrane; Oligopeptides; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Endothelin; Regional Blood Flow; Sulfonamides; Time Factors; Trinitrobenzenesulfonic Acid | 2004 |
Erythropoietin reduces the development of experimental inflammatory bowel disease.
Inflammatory bowel disease is characterized by oxidative and nitrosative stress, leukocyte infiltration, and up-regulation of the expression of intercellular adhesion molecule-1 (ICAM-1) in the colon. Erythropoietin (EPO) is a potent stimulator of erythroid progenitor cells, and its expression is enhanced by hypoxia. Here we investigate the effects EPO has on the development of experimental colitis. To address this question, we used an experimental model of colitis induced by dinitrobenzene sulfonic acid (DNBS). When compared with DNBS-treated mice, EPO (1000 IU/kg day s.c.)-treated mice subjected to DNBS-induced colitis experienced significantly lower rates in the extent and severity of the histological signs of colon injury. DNBS-treated mice experienced diarrhea and weight loss. At 4 days after administration of DNBS, the mucosa of the colon exhibited large areas of necrosis. Neutrophil infiltration (determined by histology as well as an increase in myeloperoxidase activity in the mucosa) was associated with up-regulation of ICAM-1. Immunohistochemistry for nitrotyrosine and poly(ADP-ribose) showed an intense staining in the inflamed colon. On the contrary, the treatment of DNBS-treated mice with EPO significantly reduced the degree of diarrhea and weight loss caused by administration of DNBS. EPO also caused a substantial reduction of the degree of colon injury, the rise in myeloperoxidase activity (mucosa), and the increase in staining (immunohistochemistry) for nitrotyrosine as well as the up-regulation of ICAM-1 caused by DNBS in the colon. Thus, treatment of rat with EPO reduces the degree of colitis caused by DNBS. We propose that EPO may be useful in the treatment of inflammatory bowel disease. Topics: Animals; Benzenesulfonates; Colitis; Erythropoietin; Immunohistochemistry; Inflammatory Bowel Diseases; Intercellular Adhesion Molecule-1; Interleukin-1; Intestinal Mucosa; Male; Mice; Neutrophil Infiltration; Peroxidase; Poly Adenosine Diphosphate Ribose; Recombinant Proteins; Tumor Necrosis Factor-alpha; Tyrosine | 2004 |
Dietary iron affects inflammatory status in a rat model of colitis.
Iron deficiency anemia is a common feature in inflammatory bowel disease, and oral supplementation is one of the mainstay therapies. However, there is some concern that oral iron supplementation may lead to oxidative stress and exacerbation of inflammation. Our objective was to study the effect of severely deficient, moderately deficient, normal and high iron status on oxidative stress and the course of inflammation in a rat model of colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). The rats were randomly assigned to receive the low-iron diet for 3 (moderately iron-deficient group, n = 16) or 5 (severely iron-deficient group, n = 16) wk, the normal iron diet for 2 wk (normal iron group, n = 16) or the high-iron diet for 2 wk (high-iron group, n = 16). Malondialdehyde concentration, electroparamagnetic resonance measurement, myeloperoxidase activity, and histological analysis were used to evaluate oxidative stress. Noncolitic rats in the high-iron group had higher oxidative stress parameters than those in the other groups. The induction of colitis resulted in severe inflammatory changes in the high-iron and severely iron-deficient groups, and produced higher histological scores in the colon of the normal and high-iron groups. Iron overload, oxidative stress, and inflammation were lower in the moderately iron-deficient group compared with the other 3 groups. In conclusion, we suggest that low rather than normal or high iron supplementation should be considered for the treatment of iron deficiency in inflammatory bowel disease. Topics: Animals; Colitis; Colon; Dose-Response Relationship, Drug; Ferritins; Iron; Iron, Dietary; Kidney; Liver; Male; Malondialdehyde; Osmolar Concentration; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Sulfhydryl Compounds; Trinitrobenzenesulfonic Acid | 2004 |
IL-8 is a key chemokine regulating neutrophil recruitment in a new mouse model of Shigella-induced colitis.
The lack of a mouse model of acute rectocolitis mimicking human bacillary dysentery in the presence of invasive Shigella is a major handicap to study the pathogenesis of the disease and to develop a Shigella vaccine. The inability of the mouse intestinal mucosa to elicit an inflammatory infiltrate composed primarily of polymorphonuclear leukocytes (PMN) may be due to a defect in epithelial invasion, in the sensing of invading bacteria, or in the effector mechanisms that recruit the PMN infiltrate. We demonstrate that the BALB/cJ mouse colonic epithelium not only can be invaded by Shigella, but also elicits an inflammatory infiltrate that, however, lacks PMN. This observation points to a major defect of mice in effector mechanisms, particularly the lack of expression of the CXC chemokine, IL-8. Indeed, this work demonstrates that the delivery of recombinant human IL-8, together with Shigella infection of the colonic epithelial surface, causes an acute colitis characterized by a strong PMN infiltrate that, by all criteria, including transcription profiles of key mediators of the innate/inflammatory response and histopathological lesions, mimics bacillary dysentery. This is a major step forward in the development of a murine model of bacillary dysentery. Topics: Animals; Chemokine CXCL1; Chemokine CXCL2; Chemokines; Chemokines, CXC; Colitis; Colon; Cytokines; Disease Models, Animal; Dysentery, Bacillary; Humans; Immunohistochemistry; Interleukin-8; Intestinal Mucosa; Kinetics; Lipopolysaccharides; Male; Mice; Neutrophil Infiltration; Neutrophils; Peroxidase; Recombinant Proteins; Shigella flexneri; Species Specificity; Transcription, Genetic | 2004 |
Electroacupuncture ameliorates experimental colitis induced by acetic acid in rat.
The effect of electroacupuncture (EA) on experimental colitis was investigated in Sprague-Dawley rats. Colitis was induced by intracolonic instillation of 4% acetic acid. EA (2 Hz, 0.05 ms, 2 V for 20 min) was applied to bilateral Hoku (LI-4) and Zusanli (ST-36) on 12 hrs and 36 hrs after induction of colitis. EA-treatment significantly reduced the macroscopic damage and the myeloperoxidase activity of colonic samples at 3 days post-induction of colitis. Colitic colon showed a decreased in vitro motility. However, colonic motility of EA-treated group was not significantly different from that of normal group. The anti-inflammatory effect of EA was not inhibited by a glucocorticoid receptor antagonist, RU-486, but suppressed by a beta-adrenoceptor antagonist, propranonol. These results suggest that EA-treatment has a beneficial effect on colitis, and its anti-inflammatory effect is mediated by beta-adrenoceptor activation but not by endogenous glucocorticoiddependent mechanism. Topics: Acetic Acid; Adrenergic beta-Antagonists; Animals; Carbachol; Cholinergic Agonists; Colitis; Electroacupuncture; Enzyme Inhibitors; Gastrointestinal Motility; Hormone Antagonists; Male; Mifepristone; Muscle Contraction; Muscle, Smooth; NG-Nitroarginine Methyl Ester; Peroxidase; Propranolol; Rats; Rats, Sprague-Dawley | 2004 |
Dietary resistant starch alters the characteristics of colonic mucosa and exerts a protective effect on trinitrobenzene sulfonic acid-induced colitis in rats.
The protective effect of a dietary high-amylose cornstarch (HAS) against trinitrobenzene sulfonic acid (TNBS)-induced colitis was examined in rats. Rats were fed a HAS-free basal diet or, a 15% or 30% HAS supplemented diet for 10 d, and then received intracolonic TNBS to induce colitis and fed the respective diets for a further 8 d. HAS ingestion significantly protected colonic injuries as evidenced by lower colonic myeloperoxidase activity. Rats fed the HAS diet showed greater cecal short-chain fatty acid (SCFA) production than those fed the basal diet. Further, just before TNBS administration, HAS ingestion dose-dependently increased fecal and cecal mucin contents, and protein and nucleic acid contents in the colonic mucosa. HAS ingestion also reduced colonic permeability. The protective effect of HAS ingestion on TNBS-induced colitis is perhaps exerted through alterations in colonic mucosa, possibly due to cecal SCFA production. Topics: Animals; Cecum; Colitis; Colon; Dietary Carbohydrates; Fatty Acids; Intestinal Mucosa; Mucins; Peroxidase; Rats; Rats, Wistar; Starch; Trinitrobenzenesulfonic Acid | 2004 |
Effects of the neutrophil elastase inhibitor (ONO-6818) on acetic acid induced colitis in Syrian hamsters.
Neutrophil elastase (NE) released from neutrophils during inflammation is related to tissue disturbance and organ failure. We investigated the effects of an orally active NE inhibitor, ONO-6818, on acetic acid induced colitis in Syrian hamsters. The ulcer area, hemoglobin level in the colonic lumen, NE activity, and tissue myeloperoxidase (MPO) activity in the colitis control animals were significantly increased compared to the normal control ones. Either oral or subcutaneous treatment with ONO-6818 had significant inhibitory effects on the ulcer area, hemoglobin level and NE activity in the colonic lumen, but ONO-6818 did not have a significant inhibitory effect on tissue MPO activity. We conclude that NE is closely related to the development of inflammation in acetic acid-induced colitis in Syrian hamsters and that the condition is improved by the inhibition of NE. Topics: Acetic Acid; Animals; Colitis; Cricetinae; Hemoglobins; Leukocyte Elastase; Male; Mesocricetus; Oxadiazoles; Peroxidase; Pyrimidinones; Serpins | 2004 |
Inhibition of the vanilloid receptor subtype-1 attenuates TNBS-colitis.
Primary sensory neurons are important in regard to the initiation and propagation of intestinal inflammation. The vanilloid receptor subtype-1 (VR-1) is a cation channel located on the sensory nerves that, when stimulated, release proinflammatory peptides. Previous reports have indicated that inhibition of VR-1 with capsazepine (CPZ), a VR-1 antagonist, attenuates dextran sodium sulfate (DSS) colitis in rats. DSS-induced colitis resembles ulcerative colitis with regard to its pathologic features. In this study, we examined the effect of CPZ on trinitrobenzene sulfonic acid (TNBS)-induced colitis, an experimental model of intestinal inflammation that most closely resembles the histologic and microscopic features of Crohn's disease. Colitis was induced by administering a single enema of 100 mg/kg TNBS in 50% ethanol via catheter to lightly anesthetized rats. Subsets of rats were treated with either 1 micromol/kg/ml of CPZ or CPZ-vehicle via enema for 6 days. Seven days after TNBS administration, rats were sacrificed and inflammation was assessed using a validated macroscopic damage score (MDS) and by measuring myeloperoxidase (MPO) activity. In addition, histologic examination was performed. TNBS administration resulted in reproducible chronic erosive lesions extending into the muscularis propria and extensive recruitment of neutrophils in the distal colon. MDS and MPO scores were considerably elevated in the TNBS colons when compared with the TNBS vehicle animals. TNBS rats treated with CPZ enemas exhibited a substantial reduction in MDS and MPO scores and demonstrated dramatically improved pathologic findings. Topical CPZ resulted in considerable attenuation of TNBS-induced colitis. These results support the role of VR-1 and sensory neurons with regard to intestinal inflammation. Topics: Animals; Capsaicin; Colitis; Colon; Nociceptors; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Drug; Trinitrobenzenesulfonic Acid; TRPV Cation Channels | 2004 |
The intestinal anti-inflammatory effect of quercitrin is associated with an inhibition in iNOS expression.
Quercitrin, 3-rhamnosylquercetin, is a bioflavonoid with antioxidant properties, which exerts anti-inflammatory activity in experimental colitis. In the present study, different in vivo experiments were performed in order to evaluate the mechanisms of action involved in this effect, with special attention to its effects on proinflammatory mediators, including nitric oxide (NO). Experimental colitis was induced in female Wistar rats by incorporation of dextran sodium sulfate (DSS) in drinking water. Oral treatment of quercitrin (1 or 5 mg kg(-1) day(-1)) to colitic rats ameliorated the evolution of the inflammatory process induced when administered in a preventative dosing protocol. When quercitrin (1 mg kg(-1) day(-1)) was administered on established colitis, it facilitated the recovery of the inflamed mucosa. The beneficial effects exerted by quercitrin were evidenced both histologically and biochemically, and were associated with an improvement in the colonic oxidative status, altered as a consequence of the colonic insult induced by DSS. In addition, a reduction of colonic NO synthase activity was observed, probably related to a decreased expression in the inducible form of the enzyme via downregulation in the colonic activity of the nuclear factor-kappaB. Immunohistochemical studies showed that quercitrin treatment reduced macrophage and granulocyte infiltration in the inflamed tissue. Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; Blotting, Western; Colitis; Colon; Dextran Sulfate; Enzyme Inhibitors; Female; Fluorescent Antibody Technique; Glutathione; Intestinal Mucosa; Leukotriene B4; Macrophage Activation; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Quercetin; Rats; Rats, Wistar | 2004 |
Plant phenolic 4-coumaric acid protects against intestinal inflammation in rats.
Many plants contain significant amounts of 4-coumaric acid (4CA), a compound with antioxidant properties in vitro and in vivo. The aim of this study was to assess the effects of 4CA pretreatment on DNA oxidative stress induced by intestinal inflammation in rodents.. 4CA (50 mg/kg) was administered to rats for 14 days mixed in the diet. Colitis was induced on days 13 and 14 by administering 6% (w/v) dextran sodium sulphate (DSS) in the drinking water.. In the colon mucosa, DSS treatment increased myeloperoxidase activity (P < 0.05), oxidative DNA damage (P < 0.01), and cyclooxygenase-2 (COX-2) expression (P < 0.01) and reduced superoxide dismutase-2 (SOD-2) expression (P < 0.05). It was found that treatment with 4CA prior to DSS-induced inflammation reduced oxidative DNA damage (P < 0.01), COX-2 over-expression (P < 0.01) and restored SOD-2 gene expression to control levels. Similar effects were observed with nimesulide administered p.o. (5 mg/kg, 1 day before and during DSS treatment). PGE levels in plasma and colon mucosa were increased by DSS treatment and this effect was inhibited by pretreatment with 4-CA (P < 0.01).. Mild acute intestinal inflammation induced by DSS can be inhibited by 4-CA and this action is associated with the suppression of COX-2 expression and activity. Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Antioxidants; Colitis; Coumaric Acids; Cyclooxygenase 2; Deoxyguanosine; Dextran Sulfate; Dinoprostone; DNA Damage; Glutathione; Intestinal Mucosa; Male; Oxidative Stress; Peroxidase; Plant Extracts; Propionates; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Inbred F344; Superoxide Dismutase; Xanthine Oxidase | 2004 |
A role for proteinase-activated receptor-1 in inflammatory bowel diseases.
Proteinase-activated receptor-1 (PAR1), a G protein-coupled receptor activated by thrombin, is highly expressed in different cell types of the gastrointestinal tract. The activity of thrombin and of other proteinases is significantly increased in the colon of inflammatory bowel disease (IBD) patients. Since PAR1 activation in tissues other than the gut provoked inflammation, we hypothesized that PAR1 activation in the colon is involved in the pathogenesis of IBD. Here, we demonstrate that PAR1 is overexpressed in the colon of IBD patients. In mice, intracolonic administration of PAR1 agonists led to an inflammatory reaction characterized by edema and granulocyte infiltration. This PAR1 activation-induced inflammation was dependent on B and T lymphocytes. Moreover, PAR1 activation exacerbated and prolonged inflammation in a mouse model of IBD induced by the intracolonic administration of trinitrobenzene sulfonic acid (TNBS), while PAR1 antagonism significantly decreased the mortality and severity of colonic inflammation induced by TNBS and dextran sodium sulfate. In these 2 models, colitis development was strongly attenuated by PAR1 deficiency. Taken together, these results imply an important role for PAR1 in the pathogenesis of experimental colitis, supporting the notion that PAR1 inhibition may be beneficial in the context of IBD and possibly in other chronic intestinal inflammatory disorders. Topics: Adult; Animals; B-Lymphocytes; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Humans; Immunohistochemistry; Inflammatory Bowel Diseases; Intestinal Mucosa; Kinetics; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Peptide Fragments; Permeability; Peroxidase; Receptor, PAR-1; RNA, Messenger; Survival Rate; T-Lymphocytes; Thrombin; Trinitrobenzenesulfonic Acid | 2004 |
Vanilloid receptor 1 antagonists attenuate disease severity in dextran sulphate sodium-induced colitis in mice.
Neurogenic mechanisms have been implicated in the induction of inflammatory bowel disease (IBD). Vanilloid receptor type 1 (TRPV1) has been visualized on nerve terminals of intrinsic and extrinsic afferent neurones innervating the gastrointestinal tract and local administration of a TRPV1 antagonist, capsazepine, reduces the severity of dextran sulphate sodium (DSS)-induced colitis in rats (Gut 2003; 52: 713-9(1)). Our aim was to test whether systemically or orally administered TRPV1 antagonists attenuate experimental colitis induced by 5% DSS in Balb/c mice. Intraperitoneal capsazepine (2.5 mg kg(-1), bid), significantly reduced the overall macroscopic damage severity compared with vehicle-treated animals (80% inhibition, P < 0.05); however, there was no effect on myeloperoxidase (MPO) levels. An experimental TRPV1 antagonist given orally was tested against DSS-induced colitis, and shown to reverse the macroscopic damage score at doses of 0.5 and 5.0 mg kg(-1). Epithelial damage assessed microscopically was significantly reduced. MPO levels were attenuated by approximately 50%, and diarrhoea scores were reduced by as much as 70%. These results suggest that pharmacological modulation of TRPV1 attenuates indices of experimental colitis in mice, and that development of orally active TRPV1 antagonists might have therapeutic potential for the treatment of IBD. Topics: Animals; Anticoagulants; Capsaicin; Colitis; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Inflammatory Bowel Diseases; Ion Channels; Mice; Mice, Inbred BALB C; Peroxidase; TRPV Cation Channels | 2004 |
Colonic responses to Lactobacillus farciminis treatment in trinitrobenzene sulphonic acid-induced colitis in rats.
It has recently been shown that Lactobacillus farciminis treatment exerts an anti-inflammatory effect in trinitrobenzene sulphonic acid (TNBS)-induced colitis partly through a nitric oxide release by this strain. The aim of this study was to evaluate whether L. farciminis treatment shares also the general mechanisms of action involved in the beneficial effect of probiotics in the colonic inflammatory process.. Rats received L. farciminis for 15 days before and 4 days after intracolonic administration of TNBS or vehicle. The following parameters were evaluated: macroscopic damage of colonic mucosa, myeloperoxidase activity, cytokine mucosal levels, bacterial profile in colonic content and mucosa, bacterial translocation and colonic paracellular permeability.. In the absence of TNBS, L. farciminis treatment reduced colonic paracellular permeability and increased the IL-10 level in the colonic wall. TNBS administration induced colonic macroscopic damage, associated with an increase of myeloperoxidase activity, bacterial translocation, colonic paracellular permeability and IL-1beta mucosal level, and a decrease in IL-10 mucosal level. Moreover, the bacterial profile of colonic content and mucosa was modified. All these alterations were abolished or significantly reduced by L. farciminis treatment.. As previously shown, L. farciminis treatment improves TNBS-induced colitis. This study indicates that, in addition to the nitric oxide released by this bacterial strain, the anti-inflammatory action of L. farciminis involves also normalization of colonic microflora, prevention of bacterial translocation, enhancement of barrier integrity and a decrease in the IL-1beta mucosal level. Topics: Animals; Bacterial Translocation; Colitis; Gastrointestinal Tract; Interleukin-1; Interleukin-10; Lactobacillus; Male; Permeability; Peroxidase; Probiotics; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2004 |
The comparative effects of calcium channel blockers in an experimental colitis model in rats.
In this study two calcium channel blockers (CCB), diltiazem and verapamil, which demonstrate their effects on two different receptor blockage mechanisms, were assessed comparatively in an experimental colitis model regarding the local and systemic effect spectrum.. Eighty male Swiss albino rats were divided into eight groups (n:10 each): Group I) colitis was induced with 1 ml 4% acetic acid without any medication. Group II) Sham group. Group III) Intra-muscular (IM) diltiazem was administered daily for five days before inducing colitis. Group IV) IM verapamil was administered daily for five days before inducing colitis. Group V) Transrectal (TR) diltiazem was administered with enema daily for two days before inducing colitis. Group VI) TR saline was administered four hours before inducing colitis. Group VII) TR diltiazem was administered with enema four hours before inducing colitis. Group VIII) TR verapamil was administered with enema four hours before inducing colitis. All subjects were sacrificed 48 hours after the colitis induction. The distal colon segment was assessed macroscopically and microscopically for the grade of damage, and myeloperoxidase (MPO) activity was measured.. All the data of the control colitis group (group I), including the microscopic, macroscopic and MPO activity measurements, were significantly higher than in the groups in which verapamil and diltiazem were administered over seven days (3.100+/-0.7379 to 1.300+/-0.9487 and 1.600+/-0.9661) (p<0.05). The data of the Sham group, group II, were less than the other groups in which colitis was induced (p<0.05). For the local effect spectrum, after the assessment of groups V-VIII, the control colitis group (group I) and group VI had significantly higher values than the others (3.300+/-0.4830 to 1.800+/-0.6325 and 1.700+/-0.8233 (p<0.05).. Calcium channel blockage has systemic and local effects on the colitis model. Topics: Animals; Calcium Channel Blockers; Colitis; Diltiazem; Disease Models, Animal; Drug Administration Schedule; Male; Peroxidase; Rats; Verapamil | 2004 |
Quantitative assessment and characterization of visceral nociception and hyperalgesia in mice.
Colorectal distension (CRD) is a well-characterized model of visceral nociception, which we adapted to the mouse. CRD reproducibly evoked contractions of the abdominal musculature [visceromotor response (VMR)], which was graded to stimulus intensity. The magnitude of VMR was greater in male C57BL6 and female 129S6 mice than in male 129S6 and B6.129 mice. In 129S6, C57BL6, and B6.129 mice strains, VMR was reduced dose dependently by morphine (1-10 mg/kg) and by the kappa-opioid agonist U-69593 (0.2-2 mg/kg), although U-69593 was significantly less potent in C57BL6 mice. In additional experiments, the VMR was recorded from adult male 129S6 mice before and after intracolonic administration of various irritants. Only 30% ethanol significantly enhanced responses to CRD. The colon hyperalgesia persisted for 14 days and was associated with a significant shift of the morphine dose-response function to the left. We believe this will be a useful model for study of visceral nociception and hyperalgesia, including studies of transgenic mice with mutations relevant to pain. Topics: Analgesics, Opioid; Animals; Catheterization; Colitis; Colon; Dose-Response Relationship, Drug; Electromyography; Female; Hyperalgesia; Intestinal Mucosa; Male; Mice; Mice, Inbred Strains; Morphine; Muscle Contraction; Muscle, Smooth; Nociceptors; Pain Measurement; Peroxidase; Physical Stimulation; Pregnancy; Rectum; Restraint, Physical; Sex Characteristics; Species Specificity | 2003 |
The prebiotic characteristics of fructooligosaccharides are necessary for reduction of TNBS-induced colitis in rats.
Fructooligosaccharides (FOS) increase the growth of lactic acid bacteria (LAB) and promote butyrate and lactate production. Because of these properties, FOS may benefit intestinal inflammation. The purpose of this study was to investigate the effect of FOS on colitis in rats and determine which factors are involved. Groups of rats with intracolonic trinitrobenzene sulfonic acid (TNBS)-induced colitis received intragastric infusions of 9 g/L NaCl, 1 g/d FOS or 10(11) colony-forming units (cfu)/d LAB (Experiment 1), or intracolonic infusions of 9 g/L NaCl, butyrate, lactate or butyrate + lactate with or without 10(9.5) cfu/d LAB (Experiment 2). Each infusion was administered twice daily for 14 d. Intragastric FOS reduced the gross score for inflammation (P < 0.001), myeloperoxidase (MPO) activity (P < 0.001) and pH (P < 0.001), and increased lactate (P = 0.02) and butyrate concentrations (P < 0.001) as well as LAB counts in the cecum (P < 0.01). Intragastric LAB (10(11) cfu/d) had the same beneficial effects as FOS and modified the cecal composition similarly. High doses of intracolonic butyrate and lactate reduced the indices of inflammation (P < 0.001), whereas administration of the lower concentrations found in the colon tended to decrease (P < 0.1) the gross score for inflammation and MPO activity. Addition of LAB (10(9.5) cfu/d) to the organic acids was necessary to reproduce the significant FOS-induced effects on these variables. Thus, under the experimental conditions used, FOS reduced intestinal inflammatory activity mainly by increasing LAB counts in the intestine. Topics: Analysis of Variance; Animals; Butyrates; Colitis; Lactates; Male; Oligosaccharides; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2003 |
Transforming growth factor-beta mediates intestinal healing and susceptibility to injury in vitro and in vivo through epithelial cells.
In vitro studies suggest that transforming growth factor (TGF)-beta has potent effects on gastrointestinal mucosal integrity, wound repair, and neoplasia. However, the multiplicity of actions of this peptide on many different cell types confounds efforts to define the role of TGF-beta within the intestinal epithelium in vivo. To delineate these effects selective blockade of intestinal epithelial TGF-beta activity was undertaken through targeted expression of a dominant-negative (DN) TGF-beta RII to intestinal epithelial cells in vitro and in vivo. Stable intestinal epithelial cell (IEC)-6 lines overexpressing TGF-beta RII-DN (nucleotides -7 to 573) were established. Transgenic mice overexpressing TGF-beta RII-DN under the regulation of a modified liver fatty acid-binding promoter (LFABP-PTS4) were constructed. In vitro healing was assessed by wounding of confluent monolayers. Colitis was induced by the addition of dextran sodium sulfate (2.5 to 7.5% w/v) to their drinking water. Overexpression of TGF-beta RII-DN in intestinal epithelial cell-6 cells resulted in a marked reduction in cell migration and TGF-beta-stimulated wound healing in vitro. TGF-beta RII-DN transgenic mice did not exhibit baseline intestinal inflammation or changes in survival, body weight, epithelial cell proliferation, aberrant crypt foci, or tumor formation. TGF-beta RII-DN mice were markedly more susceptible to dextran sodium sulfate-induced colitis and exhibited impaired recovery after colonic injury. TGF-beta is required for intestinal mucosal healing and TGF-beta modulation of the intestinal epithelium plays a central role in determining susceptibility to injury. Topics: Animals; Cell Division; Cell Line; Cell Movement; Colitis; Colon; Granulocytes; Humans; Intestinal Mucosa; Mice; Mice, Inbred DBA; Mice, Transgenic; Peroxidase; Promoter Regions, Genetic; Recombinant Proteins; Transforming Growth Factor beta; Wound Healing | 2003 |
Effects of dosmalfate, a new cytoprotective agent, on acute and chronic trinitrobenzene sulphonic acid-induced colitis in rats.
Activated neutrophils and proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) are clearly involved in the pathogenesis of bowel disease. Increased expression of epidermal growth factor-receptor (EGF receptor) has been reported for the colon mucosa surrounding areas of ulceration, suggesting a pivotal role in mucosal defence and repair. In this study, we examined the effects of dosmalfate, a new flavonoid derivative compound (diosmin heptakis) with antioxidant and cytoprotective properties, on acute and chronic experimental trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. The inflammation response was assessed by neutrophil infiltration as evaluated by histology and myeloperoxidase activity. Mucosal TNF-alpha production and histological analysis of the lesions was also carried out. In addition, we studied the expression of the EGF receptor inmunohistochemically during the healing of TNBS-induced chronic colitis. A 2-day treatment with 400 or 800 mg/kg of dosmalfate ameliorated the colon damage score and the incidence of adhesions. It also significantly (P<0.05) decreased myeloperoxidase activity and colonic mucosal production of TNF-alpha. Chronic treatment (14 days) with 800 mg/kg/day of dosmalfate also had significant protective effects on TNBS-induced colitis which were reflected by significant attenuation (P<0.05) of the damage score while the inflammatory indicators were not improved. The chronic beneficial effect of dosmalfate was apparently related to the enhancement of EGF receptor expression. These findings confirm the protective effects of dosmalfate in acute and chronic experimental colitis. Topics: Acute-Phase Reaction; Animals; Colitis; Colon; Diosmin; ErbB Receptors; Immunohistochemistry; Inflammation; Instillation, Drug; Intestinal Mucosa; Male; Peroxidase; Protective Agents; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2003 |
Efficacy of repifermin (keratinocyte growth factor-2) against abnormalities in gastrointestinal mucosal transport in a murine model of colitis.
Human keratinocyte growth factor-2 (KGF-2) is a member of the fibroblast growth factor family that promotes healing of experimental small intestinal ulceration and colitis. The aim of this study was to determine whether repifermin, a truncated form of recombinant human KGF-2, reverses abnormalities in colonic mucosal transport in a murine model of dextran sulfate sodium (DSS)-induced colitis. Male Swiss-Webster mice were given 4% DSS in drinking water for 7 days and then normal drinking water for 3 days. Repifermin (5 mg kg(-1), i.p.) or vehicle was administered daily for 7 days starting on Day 4 of DSS exposure. On Day 10, net ion transport was measured electrophysiologically in colonic mucosal sheets. Repifermin significantly reduced DSS-induced colonic inflammation measured by tissue myeloperoxidase activity. Concurrently, in colonic tissue taken from mice treated with repifermin, there was a normalization of basal potential difference and short circuit current, and an improvement in the secretory responses to stimulation of muscarinic and ganglionic cholinoceptors. In control mice, repifermin did not interact directly with colonic epithelial cells or intramural neurones to induce immediate changes in net electrogenic transport. The results suggest that repifermin therapy may improve the mucosal electrogenic transport that is impaired during colitis. Topics: Animals; Anticoagulants; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Electrophysiology; Fibroblast Growth Factor 10; Fibroblast Growth Factors; Inflammation; Intestinal Mucosa; Ion Transport; Male; Mice; Peroxidase | 2003 |
Attenuated mild colonic inflammation and improved survival from severe DSS-colitis of transgenic Cu/Zn-SOD mice.
Mucosal tissue damage in chronic inflammatory bowel disease (IBD) is partly caused by an enduring exposure to excessive amounts of reactive oxygen metabolites (ROM). To protect themselves from the toxic effects of ROM, most intestinal cell types constitutively express the highly specific, key ROM-neutralizing cytosolic enzyme Cu/Zn-superoxide dismutase (SOD). Under inflammatory conditions, however, its protein and activity levels have consistently been reported as being decreased. To elucidate a direct functional relationship between intracellular Cu/Zn-SOD expression and intestinal inflammation, we investigated the effects of transgenic human Cu/Zn-SOD overexpression in acute and chronic murine dextran sodium sulfate (DSS)-induced colitis. When subjected to a mild form of acute colitis, the Cu/Zn-SOD overexpressing mice showed a significantly lower colonic activity of neutrophilic myeloperoxidase (MPO) than their nontransgenic littermates. This difference was particularly evident in the male animals. In contrast, a severe acute colitis did not lead to any differences in MPO activity between both groups. Yet, when the animals were subsequently allowed to recover, MPO levels were again significantly lower in the transgenes, suggesting an involvement of Cu/Zn-SOD in, particularly, the clearance of neutrophils. Specific, immunohistochemical identification of neutrophils confirmed the validity of the MPO activity measurements. In addition, transgenic animals showed a remarkable survival benefit from severe DSS colitis over their nontransgenic littermates, particularly during or shortly after the acute inflammatory phase. During the chronic inflammatory phase, which was not characterized by massive neutrophil infiltration, no effects of Cu/Zn-SOD overexpression were noted. Paradoxically, overexpression of Cu/Zn-SOD did not obviously improve the colitis-related (oxidative) injury or symptoms at any stage of the experiment. Surprisingly, however, we did observe a pronounced male gender preference for DSS susceptibility that was reflected by increased male colitis mortality. Our findings provide direct in vivo evidence for a protective, neutrophil-related role for Cu/Zn-SOD in intestinal inflammation. As such, they support the concept of SOD-based (adjunct) antioxidant treatment strategies for inflammatory bowel disease. Topics: Acute Disease; Animals; Antioxidants; Catalase; Chronic Disease; Colitis; Colon; Dextran Sulfate; DNA Primers; Female; Glutathione Peroxidase; Humans; Indicators and Reagents; Inflammation; Male; Metabolic Clearance Rate; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neutrophils; Oxidation-Reduction; Oxidative Stress; Peroxidase; Polymerase Chain Reaction; Superoxide Dismutase; Survival Rate | 2003 |
Roquinimex inhibits dextran sodium sulfate-induced murine colitis.
Roquinimex is a modulator of the immune system and has been shown to attenuate induction of several inflammatory and autoimmune diseases. The objective of the present study was to determine the efficacy of roquinimex in a model of murine colitis.. For this purpose, Balb/c mice were exposed to 5% dextran sodium sulfate (DSS) in the drinking water for five to six days. Roquinimex (300 mg kg(-1) day(-1)) was administered by subcutaneous (s.c.) injection 3 days prior to and throughout the treatment period with DSS. In separate experiments, 300 mg kg(-1) day(-1) of roquinimex was given therapeutically after initiation of DSS challenge.. DSS provoked clinical signs of colitis, reduced crypt height (CH) and increased mucosal damage score (MDS) as analyzed by histology. In addition, challenge with DSS increased the colonic content of myeloperoxidase (MPO). Prophylactic administration of DSS-treated mice with roquinimex significantly reduced clinical signs of colitis, MDS and the CH-reduction. Moreover, in roquinimex treated animals, the MPO activity was significantly reduced by more than 50% compared to DSS control mice. Notably, therapeutic administration of roquinimex in DSS-treated mice also significantly inhibited the MDS, CH-reduction and MPO activity.. These findings suggest that roquinimex strongly inhibits murine colitis and may provide a novel pharmacological approach to treat inflammatory bowel disease. Topics: Adjuvants, Immunologic; Animals; Colitis; Colon; Dextran Sulfate; Hydroxyquinolines; Injections, Subcutaneous; Male; Mice; Mice, Inbred BALB C; Peroxidase | 2003 |
Acetic acid-derived prostaglandin-dependent colonic adaptive cytoprotection is preserved in chronic colitis: role of cyclo-oxygenase.
We recently reported the phenomenon of prostaglandin-dependent colonic adaptive cytoprotection (CAP) against acute colonic injury induced by acetic acid (AA) in the normal colon. This study investigated whether the CAP is preserved in the chronic inflamed colon.. Normal rats and a chronic colitis model, induced by trinitrobenzene sulfonic acid, received an intracolonal administration (0.5 ml) of saline or AA at low concentration (1%) followed by high concentration (8%) 30 min later. The distal colon was removed 48 h after 8% AA administration, and colitis was assessed by macroscopic scoring and measurement of the myeloperoxidase (MPO) activity. Indomethacin (5 mg/kg), a nonselective cyclo-oxygenase (COX) inhibitor, or N-[2-cyclohexyloxy-4-nitrophenyl] methane-sulfonamide (NS398, 1 mg/kg), a COX type 2 selective inhibitor, was injected intraperitoneally 1 h before pretreatment with 1% AA.. Intracolonal administration of 8% AA induced colonic mucosal damage (macroscopic score 10.0+/-0.9) and elevated MPO activity (2.8+/-0.2 U/g), which were significantly reduced to 3.3+/-0.8 and 1.8+/-0.2 U/g by 1% AA pretreatment, respectively. Indomethacin abolished the gross mucosal protective effect by 1% AA pretreatment in 8% AA-derived colitis in normal rats while the NS398 had no effect. Both indomethacin and NS398 reversed the MPO activity reduction induced by 1% AA pretreatment. In chronic inflamed colon 8% AA treatment resulted in an increase in the macroscopic score to 11.5+/-0.4 from 4.7+/-0.4, but not the MPO activity, which was significantly reduced to 5.7+/-0.9 by 1% AA pretreatment. This gross mucosal protective effect by 1% AA pretreatment in chronic inflamed colon was reversed by indomethacin while the NS398 had no effect.. These data show that COX-1 and COX-2 derived prostaglandins induced by low concentration AA pretreatment reduce the colonic mucosal injury and the increase in the MPO activity in colitis, respectively. The protective effect of COX-1 is preserved in chronic inflamed colon. These findings support the existence of a low concentration of AA-derived prostaglandin-dependent CAP and suggest that colonic AA, which is derived from bacterial breakdown of carbohydrate and protein in the colon, plays a crucial role in the endogenous defense mechanisms. Topics: Acetic Acid; Animals; Colitis; Cyclooxygenase Inhibitors; Disease Models, Animal; Dose-Response Relationship, Drug; Indicators and Reagents; Indomethacin; Injections, Intraperitoneal; Male; Peroxidase; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Inbred F344; Sulfonamides | 2003 |
Possible role of mucosal mast cells in the recovery process of colitis induced by dextran sulfate sodium in rats.
To clarify the role of mucosal mast cells in the lesion sites of colitis induced by dextran sulfate sodium (DSS) in rats, we investigated the histological changes and alterations relevant to mucosal mast cells in the spontaneous recovery process of colitis. Oral administration of 4% DSS solution for 11 days resulted in surface epithelial loss, crypt loss and goblet cell depletion in the rectal mucosa. A marked infiltration of inflammatory cells into the mucosa, which was consistent with a significant increase in myeloperoxidase (MPO) activity, was observed. In addition, mucosal mast cell number and rat mast cell protease (RMCP) I and II levels in the rectum increased at day 0 after DSS treatment, and most of the mucosal mast cells were degranulated. After replacing 4% DSS solution with water, re-epithelialization and restoration of goblet cells were observed at day 5 and day 10, respectively, but crypt damage was hardly recovered even at day 20. The elevated myeloperoxidase activity was significantly decreased from day 5 after DSS treatment. The increased number of mucosal mast cells was further elevated up to about 1.5-fold at day 10 and day 20 after DSS treatment and little degranulation was observed. In the spontaneous recovery process, the increased rat mast cell protease II level in the rectum was maintained for 20 days, while the increased rat mast cell protease I level was gradually decreased and recovered to control level. These results suggest that proliferated mucosal mast cells remained for 20 days, although most of infiltrated inflammatory cells disappeared in spontaneous recovery process of colitis. It may therefore be presumed that proliferated mucosal mast cells play a role in spontaneous recovery process of the colitis induced by DSS. Topics: Animals; Cell Count; Chymases; Colitis; Dextran Sulfate; Disease Models, Animal; Intestinal Mucosa; Male; Mast Cells; Peroxidase; Proctitis; Rats; Rats, Sprague-Dawley; Rectum; Serine Endopeptidases | 2003 |
The adenosine A3 receptor agonist, N6-(3-iodobenzyl)-adenosine-5'-N-methyluronamide, is protective in two murine models of colitis.
This study evaluated the effects of the adenosine A(3) receptor agonist, N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA), in two murine models of colitis, the dextran sodium sulphate-induced colitis and the spontaneous colitis found in interleukin-10 gene deficient mice. IB-MECA was given orally twice a day at a dose of either 1 or 3 mg/kg/day. Evaluation of colon damage and inflammation was determined grossly (body weight, rectal bleeding) and biochemically (colon levels of myeloperoxidase, malondialdehyde, chemokines and cytokines). There was significantly increased inflammatory cell infiltration into the colon associated with an increase in colon levels of cytokines and chemokines; with subsequent free radical related damage in both dextran sodium sulphate-induced colitis and 10-week-old interleukin-10(-/-) mice. IB-MECA protected in both models against the colitis induced inflammatory cell infiltration and damage and attenuated the increases in colon inflammatory cytokine and chemokine levels. Thus activation of the adenosine A(3) receptor is effective in protecting against colitis. Topics: Adenosine; Animals; Chemokine CCL4; Chemokine CXCL2; Chemokines; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Gastrointestinal Hemorrhage; Interleukin-1; Interleukin-12; Interleukin-6; Macrophage Inflammatory Proteins; Male; Malondialdehyde; Mice; Mice, Inbred BALB C; Mice, Knockout; Peroxidase; Purinergic P1 Receptor Agonists; Receptor, Adenosine A3; Rectal Diseases; Weight Loss | 2003 |
Impact on the bowel of amtolmetin guacyl, a new gastroprotective non-steroidal anti-inflammatory drug.
Amtolmetin guacyl (MED15) is a new non-steroidal anti-inflammatory drug (NSAID) which shares anti-inflammatory, analgesic and antipyretic activity with the other drugs of the NSAID family but which shows, unexpectedly, strong gastroprotective activity similar to misoprostol. This effect has been attributed to the presence in its molecule of a vanillic moiety responsible for stimulation of capsaicin receptors present throughout the length of the gastrointestinal tract. MED15 shows antispasmodic activity in the bowel against a number of agonists and compares favourably with reference compounds. In in vivo indomethacin-induced rat ileitis, MED15 heals better than 5-aminosalicylic acid and sulfasalazine, as well as down-regulating intestinal wall myeloperoxidase content. In acetic acid-induced colitis in the rat, levels of malondialdehyde were found to be more markedly reduced with MED15 than with 5-aminosalicylic acid. In contrast with the effect in the stomach, MED15 protective effect in the bowel appears to be unrelated to nitric oxide (NO) production. The MED15 enteroprotective effect is related to stimulation of intestinal capsaicin receptors as demonstrated by the loss of protective effect in the presence of capsazepine, a specific receptor antagonist of capsaicin. In conclusion, following the favourable results obtained in animal models and notwithstanding the pharmacological effects typical of an NSAID, MED15 may rationally be proposed for the treatment of various human colitis conditions and Crohn's disease. Topics: Acetic Acid; Aminosalicylic Acids; Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Dose-Response Relationship, Drug; Glycine; Guinea Pigs; Ileitis; Ileum; In Vitro Techniques; Indomethacin; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Pyrroles; Rats; Rats, Wistar; Sulfasalazine; Ulcer | 2003 |
Amelioration of TNBS-induced colon inflammation in rats by phospholipase A2 inhibitor.
The pathophysiology of inflammatory bowel disease (IBD) involves the production of diverse lipid mediators, namely eicosanoids, lysophospholipids, and platelet-activating factor, in which phospholipase A2 (PLA2) is the key enzyme. Accordingly, it has been postulated that control of lipid mediator production by inhibition of PLA2 would be useful for the treatment of IBD. This hypothesis was tested in the present study by examining the therapeutic effect of a novel extracellular PLA2 inhibitor (ExPLI), composed of carboxymethylcellulose-linked phosphatidylethanolamine (CMPE), on trinitrobenzenesulfonic acid-induced colitis. Intraperitoneal administration of CMPE suppressed the colitis as measured by mortality rate, intestinal permeability, plasma PLA2 activity, intestinal myeloperoxidase activity, and histological morphometry. Current therapeutic approaches for inflammatory conditions focus on the selective control of a lipid mediator(s) (e.g., prostaglandins or leukotrienes). The present study supports the concept that inclusive control of lipid mediator production by PLA2 inhibition is a plausible approach to the treatment of colitis and introduces the ExPLIs as a prototype of a novel NSAID for the treatment of intestinal inflammation. Topics: Animals; Cellulase; Colitis; Colon; Drug Combinations; Enzyme Inhibitors; Glycoside Hydrolases; Intestinal Mucosa; Permeability; Peroxidase; Phosphatidylethanolamines; Phospholipases A; Phospholipases A2; Rats; Rats, Inbred Strains; Trinitrobenzenesulfonic Acid | 2003 |
Anti-inflammatory properties of the mu opioid receptor support its use in the treatment of colon inflammation.
The physiologic role of the mu opioid receptor (MOR) in gut nociception, motility, and secretion is well established. To evaluate whether MOR may also be involved in controlling gut inflammation, we first showed that subcutaneous administration of selective peripheral MOR agonists, named DALDA and DAMGO, significantly reduces inflammation in two experimental models of colitis induced by administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) or peripheral expansion of CD4(+) T cells in mice. This therapeutic effect was almost completely abolished by concomitant administration of the opioid antagonist naloxone. Evidence of a genetic role for MOR in the control of gut inflammation was provided by showing that MOR-deficient mice were highly susceptible to colon inflammation, with a 50% mortality rate occurring 3 days after TNBS administration. The mechanistic basis of these observations suggests that the anti-inflammatory effects of MOR in the colon are mediated through the regulation of cytokine production and T cell proliferation, two important immunologic events required for the development of colon inflammation in mice and patients with inflammatory bowel disease (IBD). These data provide evidence that MOR plays a role in the control of gut inflammation and suggest that MOR agonists might be new therapeutic molecules in IBD. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; CD4-Positive T-Lymphocytes; Colitis; Colon; Cytokines; Disease Models, Animal; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, SCID; Naloxone; Narcotic Antagonists; Oligopeptides; Peroxidase; Receptors, Opioid, mu; Trinitrobenzenesulfonic Acid | 2003 |
Cholinergic pathways modulate experimental dinitrobenzene sulfonic acid colitis in rats.
Recent studies have suggested that neuroimmune interactions modulate intestinal mucosal immune responses. In the current study, we examined the role of cholinergic pathways in modulating the severity of acute dinitrobenzene sulfonic acid colitis, using pharmacological agents to suppress acetylcholinesterase in Sprague-Dawley rats, and evaluating the colitis in the cholinergic hyperresponsive Flinder's sensitive line rats and their control counterparts, the Flinder's resistant line. Colitis was induced by intrarectal dinitrobenzene sulfonic acid (80 mg x ml(-1) in 50% ethanol); controls received intrarectal saline. Sprague-Dawley rats received an acetylcholinesterase inhibitor, physostigmine (50 microg x kg(-1) s.c.) or neostigmine (50 microg x kg(-1) s.c.), 30 min prior to intrarectal dinitrobenzene sulfonic acid; controls received saline vehicle. On day 5, the macroscopic damage score, myeloperoxidase activity (an estimate of granulocyte infiltration) and smooth muscle thickness were evaluated in the inflamed colonic segment. Significant increases in macroscopic damage score and colonic smooth muscle thickness were observed in Sprague-Dawley and Flinder's Resistant Line rats on day 5 following intrarectal dinitrobenzene sulfonic acid compared to saline controls. Increased myeloperoxidase activity was also observed in dinitrobenzene sulfonic acid-treated Sprague-Dawley rats and Flinder's Resistant Line rats. In contrast, Flinder's Sensitive Line rats failed to demonstrate a significant rise in macroscopic damage, smooth muscle layer thickness, or myeloperoxidase activity on day 5 following intrarectal dinitrobenzene sulfonic acid when compared to saline-treated Flinder's Sensitive Line controls. Neostigmine and physostigmine treatment prior to intrarectal dinitrobenzene sulfonic acid significantly attenuated macroscopic damage score, myeloperoxidase activity and smooth muscle thickness on day 5 compared to colitic Sprague-Dawley controls. Significantly greater reductions in myeloperoxidase activity were observed with physostigmine vs. neostigmine pretreatment. These data suggest that cholinergic pathways modulate the acute colonic inflammatory response associated with the dinitrobenzene sulfonic acid model, with central pathways exerting a greater protective effect relative to peripheral pathways. Further studies are required to determine the contributions of sites in the nervous system and neuro-effector junctions. Topics: Animals; Benzenesulfonates; Cholinergic Fibers; Colitis; Muscarinic Agonists; Neural Pathways; Peroxidase; Rats; Rats, Sprague-Dawley | 2003 |
Thymoquinone protects against experimental colitis in rats.
The present work was done to investigate the possible effects of thymoquinone on acetic acid-induced colitis in rats. Colitis was induced by intracolonic injection of 3% acetic acid. Several parameters including macroscopic score, histopathological and biochemical, were determined to assess the degree of protection. Biochemical parameters such as myeloperoxidase activity, reduced glutathione levels, platelet activating factor (PAF) and histamine were measured following standard assay procedures. The study showed that pretreatment of rats for 3 days with thymoquinone (10 mg/kg) was able to give complete protection against acetic acid-induced colitis an effect significantly higher than sulfasalazine (500 mg/kg) control group. The smaller dose of thymoquinone (5 mg/kg) produced partial protection. Moreover, the biochemical and histopathological changes were reversed and brought towards the control. These results suggest a beneficial effect of thymoquinone against experimentally-induced colitis and the possible mechanism of the protective effects may be partly due to an antioxidant action. Topics: Acetic Acid; Animals; Benzoquinones; Colitis; Colon; Disease Models, Animal; Dose-Response Relationship, Drug; Glutathione; Histamine; Male; Peroxidase; Platelet Activating Factor; Rats; Rats, Wistar; Rectum | 2003 |
Curcumin, the major component of food flavour turmeric, reduces mucosal injury in trinitrobenzene sulphonic acid-induced colitis.
1 Inflammmatory bowel disease (IBD) is characterized by oxidative and nitrosative stress, leucocyte infiltration and upregulation of proinflammatory cytokines. In this study, we have investigated the protective effects of curcumin, an anti-inflammatory and antioxidant food derivative, on 2,4,6- trinitrobenzene sulphonic acid-induced colitis in mice, a model for IBD. 2 Intestinal lesions (judged by macroscopic and histological score) were associated with neutrophil infiltration (measured as increase in myeloperoxidase activity in the mucosa), increased serine protease activity (may be involved in the degradation of colonic tissue) and high levels of malondialdehyde (an indicator of lipid peroxidation). 3 Dose-response studies revealed that pretreatment of mice with curcumin (50 mg kg(-1) daily i.g. for 10 days) significantly ameliorated the appearance of diarrhoea and the disruption of colonic architecture. Higher doses (100 and 300 mg kg(-1)) had comparable effects. 4 In curcumin-pretreated mice, there was a significant reduction in the degree of both neutrophil infiltration (measured as decrease in myeloperoxidase activity) and lipid peroxidation (measured as decrease in malondialdehyde activity) in the inflamed colon as well as decreased serine protease activity. 5 Curcumin also reduced the levels of nitric oxide (NO) and O(2)(-) associated with the favourable expression of Th1 and Th2 cytokines and inducible NO synthase. Consistent with these observations, nuclear factor-kappaB activation in colonic mucosa was suppressed in the curcumin-treated mice. 6 These findings suggest that curcumin or diferuloylmethane, a major component of the food flavour turmeric, exerts beneficial effects in experimental colitis and may, therefore, be useful in the treatment of IBD. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Curcuma; Curcumin; Cytokines; Dose-Response Relationship, Drug; Female; Intestinal Mucosa; Malondialdehyde; Mice; Mice, Inbred BALB C; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Phytotherapy; Plant Extracts; RNA, Messenger; Serine Endopeptidases; Superoxides; Trinitrobenzenesulfonic Acid | 2003 |
The free radical scavenger edaravone suppresses experimental dextran sulfate sodium-induced colitis in rats.
Recent studies suggest that the enhanced release of reactive oxygen species (ROS) plays an important role in the pathogenesis of clinical inflammatory bowel diseases (IBD) such as ulcerative colitis and Crohn's disease. In the present study, we investigated the effects of the free radical scavenger edaravone, which is used clinically as an anti-stroke agent, in the development of experimental dextran sulfate sodium (DSS)-induced colitis in rats. The rats were fed 4% (w/w of diet) DSS in standard powder chow for 8 days. The edaravone and vehicle saline were injected subcutaneously twice a day. After the experimental period, the wet colonic weight, macroscopic mucosal damaged area, histological damage score, mucosal myeloperoxidase (MPO) activity, mucosal tissue lipid peroxidate and serum interleukin-6 (IL-6) levels were measured. In the DSS-induced colitis model, edaravone treatment (1-20 mg/kg day) significantly reduced the wet colonic weight, macroscopic damaged area, and the histological damage score. Edaravone treatment also reduced mucosal MPO activity, mucosal tissue lipid peroxidate level and serum IL-6 level. In particular, edaravone at a dose of 20 mg/kg day significantly reduced mucosal MPO activity and serum IL-6 level. These results strongly support the involvement of ROS in the pathogenesis of DSS-induced colitis. A clinical effect for edaravone against IBD patients is strongly expected. Topics: Aldehydes; Animals; Antipyrine; Colitis; Edaravone; Free Radical Scavengers; Interleukin-6; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley | 2003 |
Effect of the antioxidant Mesna (2-mercaptoethane sulfonate) on experimental colitis.
Reactive oxygen species play a key role in intestinal inflammation, although interventional studies using antioxidants have shown only weak beneficial effects both in humans and animals. Hence, our aim was to examine the possible beneficial effect of the antioxidant 2-mercaptoethane sulfonate (Mesna) on experimental colitis. Colitis was induced in rats by intrarectal instillation of trinitrobenzene sulfonic acid (TNB) followed immediately by intrarectal Mesna or saline, administered for 14 days, twice daily. A beneficial effect of Mesna was observed, resulting in a significant reduction in inflammation followed by almost full recovery. iNOS mRNA expression and myeloperoxidase (MPO) activity were significantly increased in the TNB-Mesna group. These results suggest that the induction of iNOS in the presence of Mesna reduced intestinal inflammation. Mesna probably resolved this inflammation by scavenging reactive oxygen species generated by the augmented infiltration of polymorphonuclear leukocytes. Topics: Animals; Antioxidants; Colitis; Female; Mesna; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Trinitrobenzenesulfonic Acid | 2003 |
Bacterial load in animal models of acute and chronic 'reactivated' colitis.
The involvement of enteropathogenic microorganisms in the pathogenesis of inflammatory bowel disease (IBD) and their importance in the different phases of inflammation are still unknown.. To quantify the aerobic bacterial load in models of acute and chronic 'reactivated' colitis, and correlate this with damage.. Acute colitis was induced in rats by administration of trinitrobenzene sulfonic acid (TNBS) or dextran sulfate sodium (DSS). Colitis was 'reactivated' 6 weeks later by intravenous administration of TNBS. The distal colon was removed and scored macroscopically before inoculating samples.. Bacterial load in rats with acute colitis (72 h) and chronic 'reactivated' colitis or their controls was significantly higher than untreated (p < 0.05); however, there were significantly more bacteria in acute colitis than in chronic 'reactivated' or their controls (p < 0.05). Both acute and chronic 'reactivated' colitis had significantly higher damage scores than untreated animals (p < 0.05). Bacterial load and damage score were significantly correlated only with acute colitis.. The role of enteric microflora in the pathogenesis of IBD is greater during the acute phase of colitis. The correlation between bacterial load and tissue damage suggests that damage contributes to bacterial multiplication and exacerbation of colitis. Normal colonic flora may contribute to the relapse of the disease. Topics: Acute Disease; Animals; Bacteria; Chronic Disease; Colitis; Colony Count, Microbial; Dextran Sulfate; Indicators and Reagents; Male; Models, Animal; Peroxidase; Rats; Rats, Sprague-Dawley; Recurrence; Trinitrobenzenesulfonic Acid | 2003 |
Central effects of selective NK1 and NK3 tachykinin receptor agonists on two models of experimentally-induced colitis in rats.
Peripheral tachykinins (TKs) are believed to play a role in the pathogenesis of inflammatory bowel diseases (IBD). In this study we investigated changes induced by central administration of two natural TK receptor agonists, NK(1) (PG-SPI) and NK(3) (PG-KII), on trinitrobenzene sulphonic acid (TNBS)- and dextran sodium sulphate (DSS)-induced experimental colitis in rats. Colitis was induced by instilling a single intracolonic dose of TNBS 50 mgkg(-1) (0.5 ml in 50% ethanol) or by oral administration of 5% DSS for 7 days. Each group of rats was intracerebroventricularly injected daily with PG-SPI and PG-KII (0.5, 5, and 50 microgkg(-1)). On day 3, TNBS-treated animals were killed and the severity of gut inflammation was evaluated by measuring myeloperoxidase (MPO) activity, interleukin-1beta (IL-1beta) production and by scoring macroscopic and histologic colonic damage. DSS-treated animals were checked daily for the length of survival and for stool consistency and faecal blood. In the TNBS group, PG-SPI and PG-KII increased scores for the severity of colonic damage, stimulated the production of IL-1beta and increased granulocyte infiltration into the colon (MPO activity). In the DSS group, PG-SPI and PG-KII decreased the percentage of surviving animals, and increased the number of rats that developed loose stools and blood in the faeces and the MPO activity. These results indicate that centrally injected NK(1) and NK(3) tachykinin receptor agonists play a proinflammatory role in experimentally-induced colitis in rats. Topics: Animals; Colitis; Dextran Sulfate; Disease Models, Animal; Interleukin-1; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Tachykinin; Survival Rate; Time Factors; Trinitrobenzenesulfonic Acid | 2003 |
Dietary glycine prevents chemical-induced experimental colitis in the rat.
In this study, the effect of dietary glycine on experimental colitis induced by 2,4,6-trinitrobenzene sulphonic acid (TNBS) and dextran sulfate sodium (DSS) in the rat was evaluated.. Male Wistar rats were fed a diet containing 5% glycine or casein as controls starting 3 days before experiments, and were given a single intracolonic injection of TNBS (50 mg/rat, dissolved in 50% ethanol). Similarly, some rats were given 3% DSS orally in drinking water for 5 days to induce colitis as a second model. The severity of colitis was evaluated pathologically, and tissue myeloperoxidase (MPO) activity was measured. Further, mRNA and protein levels for interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, cytokine-induced neutrophil chemoattractant (CINC), and macrophage inflammatory protein (MIP)-2 were detected by reverse-transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively.. A diet containing glycine ameliorated diarrhea and body weight loss caused by TNBS, and improved both macroscopic and histologic scores of colitis significantly. TNBS-induced increases in MPO activities in the colonic tissue were blunted significantly in glycine-fed animals. Further, dietary glycine largely prevented increases in IL-1beta and TNF-alpha in the colon 2 days after TNBS, and TNBS induction of CINC and MIP-2 in the colonic tissue also was abrogated by glycine. Importantly, the protective effect of glycine was significant even when TNBS colitis was once established. Moreover, dietary glycine also was preventive in a second, DSS-induced colitis model.. Dietary glycine prevents chemical-induced colitis by inhibiting induction of inflammatory cytokines and chemokines. It is postulated that glycine may be useful for the treatment of inflammatory bowel diseases as an immunomodulating nutrient. Topics: Animals; Cells, Cultured; Chemokine CXCL2; Chemokines; Chemokines, CXC; Colitis; Colon; Cytokines; Glycine; Intercellular Signaling Peptides and Proteins; Interleukin-1; Male; Monokines; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2003 |
Evaluating the prophylactic potential of zafirlukast against the toxic effects of acetic acid on the rat colon.
The present work was conducted to assess the possible protective effects of zafirlukast against the toxic damage induced by acetic acid in rat colon. Zafirlukast is a potent and selective cysteinyl leukotriene receptor antagonist which is used mainly in the prophylaxis of bronchial asthma. Two doses of zafirlukast were used (40 and 80 mg/kg) dissolved in gum acacia and given either orally or rectally (0.5 ml/kg). Several parameters including, macroscopic score, histopathological and biochemical such as malondialdehyde (MDA), myeloperoxidase (MPO), catalase and reduced glutathione (GSH) levels were measured using standard assay procedures. The study showed that pretreatment with zafirlukast in a dose of 80 mg/kg orally produced a significant decrease in tissue malondialdehyde, myeloperoxidase, and an increase in both reduced glutathione and catalase levels, while there was no significant changes with the rectal route. The 40 mg/kg dose had no significant protective effects when given either orally or rectally. The available data indicate that the inhibition of leukotriene synthesis or action may have a role in inflammatory bowel disease (IBD) as they are considered as important mediators in this condition. Topics: Acetic Acid; Animals; Catalase; Colitis; Colon; Coloring Agents; Glutathione; Indoles; Leukotriene Antagonists; Male; Malondialdehyde; Peroxidase; Phenylcarbamates; Rats; Rats, Wistar; Sulfonamides; Tosyl Compounds | 2003 |
Effects of Rheum tanguticum polysaccharide on TNBS -induced colitis and CD4+T cells in rats.
To study the effects of Rheum tanguticum polysaccharide(-1) (RTP(-1)) on ulcerative colitis in rats induced by 2, 4, 6-trinitrophene sulphonic acid (TNBS) and their possible mechanism.. RTP1 (200 mg.kg(-1), i.g.) extracted from Rheum tanguticum Maxim. ex Regel was administrated to rats with colitis induced by TNBS for 5 d, 7 d, 10 d and 14 d, respectively. The effects of RTP1 and dexamethasone (DX, 0.2 mg.kg(-1), i.g.) were contrastively investigated. The MPO level and SOD activity were determined by chromatometry. The expansion and protein expression of CD4+T lymphocytes isolated from colon mucosae and mesenteric lymph nodes of colitis rats were performed by immunohistochemical analysis and Western-blot methods.. Treatments of RTP1 (200 mg.kg(-1), i.g.) significantly reduced diarrhea, mortality, colon mass, ulcer areas and MPO level in colon mucosae on days 5, 7, 10 and 14 (5.2+/-1.4, 5.4+/-0.7, 5.2+/-1.8, P<0.05. 3.4+/-0.8, P<0.01. 16.1+/-12.1, P<0.01. 31.8+/-8.6, 17.7+/-5.3, 12.7+/-4.1, P<0.05). The effects of RTP1 were similar to those noted above in DX group, but there were no immunosuppressive effects of DX in RTP(-1) group, such as body mass loss, thymus and spleen atrophy. The decreased number and down-regulated protein levels of CD4+T cells isolated from the colon of colitis rats treated with RTP1 were found.. RTP1 shows significantly protective effects but lower side effects on rats with colitis induced by TNBS. The mechanism may be due to the resistance to over expansion of CD4. Topics: Animals; Body Weight; CD4-Positive T-Lymphocytes; Colitis; Drugs, Chinese Herbal; Intestinal Mucosa; Male; Organ Size; Peroxidase; Phytotherapy; Polysaccharides; Rats; Rats, Sprague-Dawley; Rheum; Spleen; Superoxide Dismutase; Thymus Gland; Trinitrobenzenesulfonic Acid | 2003 |
Acute myeloid leukemia presenting as non-neutropenic colitis in an infant.
Topics: Antineoplastic Combined Chemotherapy Protocols; Colitis; Colon; Cytarabine; Daunorubicin; Dexamethasone; Etoposide; Female; Gastrointestinal Hemorrhage; Humans; Immunohistochemistry; Infant; Leukemia, Myeloid, Acute; Leukemic Infiltration; Leukocyte Common Antigens; Peroxidase; Sigmoidoscopy; Thioguanine | 2003 |
Anti-inflammatory effects of leptin and cholecystokinin on acetic acid-induced colitis in rats: role of capsaicin-sensitive vagal afferent fibers.
Leptin and cholecystokinin (CCK) have a synergistic interaction in the suppression of food intake, and afford similar gastroprotective activity. The present study was designed to investigate the putative protective effects of CCK and leptin on acute colonic inflammation. Leptin or CCK-8s was injected to rats intraperitoneally immediately before and 6 h after the induction of colitis with acetic acid. CCK-A receptor antagonist (L-364,718) or CCK-B receptor antagonist (L-365,260) was injected intraperitoneally 15 min before leptin or CCK treatments. In a group of rats, vagal afferent fibers were denervated by topical application of capsaicin on the cervical vagi. Rats were decapitated at 24 h, and the distal 8 cm of the colon were removed for macroscopic scoring, determination of tissue wet weight index (WWI), histologic assessment and tissue myeloperoxidase (MPO) activity. All inflammation parameters were increased by acetic acid-induced colitis compared to control group. Leptin or CCK-8s treatment reduced these parameters in a similar manner, while co-administration of leptin and CCK was found to be more effective in reducing the macroscopic score and WWI. CCK-8s-induced reduction in the score and WWI was prevented by CCK-A, but not by CCK-B receptor antagonist, whereas neither antagonist altered the inhibitory effect of leptin on colitis-induced injury. On the other hand, perivagal capsaicin prevented the protective effects of both CCK-8s and leptin on colitis. Our results indicate that leptin and CCK have anti-inflammatory effects on acetic acid-induced colitis in rats, which appear to be mediated by capsaicin-sensitive vagal afferent fibers involving the reduction in colonic neutrophil infiltration. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Capsaicin; Cholecystokinin; Colitis; Colon; Female; Leptin; Male; Organ Size; Peroxidase; Rats; Rats, Wistar; Vagus Nerve | 2003 |
Visceral hypersensitivity and altered colonic motility after subsidence of inflammation in a rat model of colitis.
Irritable bowel syndrome (IBS) is a functional bowel disorder characterized by visceral hypersensitivity and altered bowel motility. There is increasing evidence suggesting the role of inflammation in the pathogenesis of IBS, which addresses the possibility that formerly established rat model of colitis could be used as an IBS model after the inflammation subsided.. Colitis was induced by intracolonic instillation of 4% acetic acid in male Sprague-Dawley rats. The extent of inflammation was assessed by histological examination and myeloperoxidase (MPO) activity assay. After subsidence of colitis, the rats were subjected to rectal distension and restraint stress, then the abdominal withdrawal reflex and the number of stress-induced fecal output were measured, respectively.. At 2 days post-induction of colitis, the colon showed characteristic inflammatory changes in histology and 8-fold increase in MPO activity. At 7 days post-induction of colitis, the histological features and MPO activity returned to normal. The rats at 7 days post-induction of colitis showed hypersensitive response to rectal distension without an accompanying change in rectal compliance, and defecated more stools than control animals when under stress.. These results concur largely with the characteristic features of IBS, visceral hypersensitivity and altered defecation pattern in the absence of detectable disease, suggesting that this animal model is a methodologically convenient and useful model for studying a subset of IBS. Topics: Acetic Acid; Animals; Biomarkers; Colitis; Disease Models, Animal; Inflammation; Irritable Bowel Syndrome; Male; Pain; Peroxidase; Rats; Rats, Sprague-Dawley | 2003 |
Protective effect of angelica sinensis polysaccharide on experimental immunological colon injury in rats.
To study the effect of angelica sinensis polysaccharide (ASP) on immunological colon injury and its mechanisms in rats.. Immunological colitis model of rats was induced by intracolon enema with 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) and ethanol. The experimental animals were randomly divided into normal control, model control, 5-aminosalicylic acid therapy groups and three doses of ASP therapy groups. The 6 groups were treated intracolonically with normal saline, normal saline, 5-aminosalicylic acid (100 mg.kg(-1)), and ASP daily (8:00 am) at the doses of 200, 400 and 800 mg.kg(-1) respectively for 21 days 7 d following induction of colitis. The rat colon mucosa damage index (CMDI), the histopathological score (HS), the score of occult blood test (OBT), and the colonic MPO activity were evaluated. The levels of SOD, MDA, NO, TNF-alpha, IL-2 and IL-10 in colonic tissues were detected biochemically and immunoradiometrically. The expressions of TGF-beta and EGF in colonic tissues were also determined immunochemically.. Enhanced colonic mucosal injury, inflammatory response and oxidative stress were observed in colitis rats, which manifested as significant increases of CMDI, HS, OBT, MPO activity, MDA and NO contents, as well as the levels of TNF-alpha and IL-2 in colonic tissues, although colonic TGF-beta protein expression, SOD activity and IL-10 content were significantly decreased compared with the normal control (P<0.01). However, these parameters were found to be significantly ameliorated in colitis rats treated intracolonically with ASP at the doses of 400 and 800 mg.kg(-1) (P<0.05-0.01). Meantime, colonic EGF protein expression in colitis rats was remarkably up-regulated.. ASP has a protective effect on immunological colon injury induced by TNBS and ethanol enema in rats, which was probably due to the mechanism of antioxidation, immunomodulation and promotion of wound repair. Topics: Angelica sinensis; Animals; Colitis; Colonic Diseases; Disease Models, Animal; Drugs, Chinese Herbal; Female; Interleukin-10; Interleukin-2; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Phytotherapy; Polysaccharides; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Wounds and Injuries | 2003 |
The intestinal anti-inflammatory activity of UR-12746S on reactivated experimental colitis is mediated through downregulation of cytokine production.
UR-12746S (dersalazine sodium) is cleaved by colonic bacteria delivering the PAF antagonist UR-12715 and 5-ASA. This study describes the anti-inflammatory activity of UR-12746S in an experimental model of reactivated colitis and its effects on cytokine production.. Rats were initially rendered colitic by a colonic instillation of 10 mg of trinitrobenzenesulphonic acid (TNBS) dissolved in 0.25 ml of 50 % ethanol, and colitis was reactivated two weeks after by a second administration of the same dose of TNBS. Two groups of colitic rats received UR-12746S (25 and 50 mg/kg daily, p.o.) and colonic damage was evaluated every week for 4 weeks. Different biochemical markers of colonic inflammation were assayed: MPO activity and cytokine (IL-1beta and TNFalpha) levels. Also, the in vitro effects of UR-12715 and 5-ASA on cytokine production were assayed.. UR-12746S showed anti-inflammatory effect in reactivated colitis in rats, as evidenced by a significant reduction in MPO activity. Both doses of UR-12746S decreased IL-1beta production, while only the highest dose assayed inhibited TNFalpha production. In vitro studies revealed that UR-12715 or 5-ASA (from 10(-6) to 10(-4) M) inhibited IL-8 production (30-40%) in HT-29 cells when incubated with LPS. This inhibitory effect was enhanced when both compounds were administered simultaneously at 10(-4) M. In addition, UR-12715 inhibited IL-1beta or TNFalpha production in THP-1 or U937 cells, respectively, when these cells were stimulated by PMA and LPS; whereas 5-ASA only showed a weak effect in inhibiting IL-1beta production.. UR-12746S was able to prevent relapse in experimental colitis and inhibition of proinflammatory cytokine production participates in the intestinal anti-inflammatory activity exerted by this compound. Topics: Aminosalicylic Acids; Animals; Anti-Inflammatory Agents, Non-Steroidal; Aza Compounds; Azo Compounds; Cell Line; Colitis; Colon; Cytokines; Down-Regulation; Female; Inflammation Mediators; Interleukin-1; Interleukin-8; Mesalamine; Neutrophil Infiltration; Peroxidase; Platelet Activating Factor; Rats; Rats, Wistar; Secondary Prevention; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2003 |
Effects of intrarectal and intraperitoneal N(G)-nitro-L-arginine methyl ester treatment in 2,4,6-trinitrobenzenesulfonic acid induced colitis in rats.
Inflammatory bowel disease (IBD) has been associated with an increased generation of nitric oxide (NO). Different authors have shown that NO in IBD can be either harmful or protective. The aim of this study was to investigate the efficiency of intrarectal (i.r.) and intraperitoneal (i.p.) application of N(G)-nitro-L-arginine methyl ester (L-NAME), a non-specific nitric oxide synthase inhibitor, in experimental acute colitis in the rats. Acute colitis was induced in rats by 2,4,6-trinitrobenzenesulfonic acid (TNBS) and ethanol. Twenty-eight rats were divided into four groups. L-NAME (50 mg/kg/day) was administered i.p. (Group 1) and i.r. (Group 2) for 7 days following the day when colitis was induced. Group 3 rats were not given any treatment after induction of colitis. Control group rats were given saline solution i.r. instead of TNBS. The presence of hyperemia, inflammation and ulcer was evaluated to score of macroscopic morphologic damage. The severity of colitis was assessed by microscopic criteria including ulceration, mucus cell depletion, crypt abscesses, inflammatory cysts, mucosal atrophy, edema, inflammatory cell infiltration, and vascular dilatation. Rectal tissue myeloperoxidase (MPO) activity and serum-rectal tissue nitrite levels were measured. Serum and rectal tissue nitrite levels increased in Group 3 rats. Both i.p. and i.r. L-NAME treatment significantly reduced serum and rectal tissue nitrite levels, but no effect on MPO activity and histologic damage score was observed. Under the present conditions we concluded i.r. and i.p. L-NAME treatment, applied at the dosage of 50 mg/kg/day, does not have any protective effect on the colonic injury. Topics: Acute Disease; Administration, Rectal; Animals; Colitis; Disease Models, Animal; Drug Therapy, Combination; Enzyme Inhibitors; Ethanol; Injections, Intraperitoneal; Male; NG-Nitroarginine Methyl Ester; Nitrites; Peroxidase; Rats; Rats, Sprague-Dawley; Rectum; Treatment Outcome; Trinitrobenzenesulfonic Acid | 2003 |
GPI 6150, a PARP inhibitor, reduces the colon injury caused by dinitrobenzene sulfonic acid in the rat.
Poly (ADP-ribose) polymerase, a nuclear enzyme activated by DNA strand breaks, has been shown to play an important role in the pathogenesis of inflammatory bowel disease. Here we investigate the effects of 1,11b-dihydro-[2H]benzopyrano [4,3,2-de]isoquinolin-3-one (GPI 6150), a new poly (ADP-ribose) polymerase inhibitor, in animal models of experimental colitis. Colitis was induced in rats by intra-colonic instillation of dinitrobenzene sulfonic acid. Rats experienced hemorrhagic diarrhea and weight loss. At 4 days after administration of dinitrobenzensulfonic acid, the mucosa of the colon exhibited large areas of necrosis. Neutrophil infiltration (determined by histology and an increase in myeloperoxidase activity in the mucosa) was associated with up-regulation of ICAM-1. Immunohistochemistry for poly (ADP-ribose) showed an intense staining in the inflamed colon. GPI 6150 (20 or 40 mg/kg daily, i.p.) significantly reduced the degree of hemorrhagic diarrhea and weight loss caused by administration of dinitrobenzensulfonic acid. GPI 6150 also caused a substantial reduction of (i) the degree of colon injury, (ii) the rise in myeloperoxidase activity (mucosa), (iii) the increase in the tissue levels of malondialdehyde, (iv) the increase in staining (immunohistochemistry) for poly (ADP-ribose), as well as (v) the upregulation of ICAM-1 and P-selectin caused by dinitrobenzensulfonic acid in the colon. Thus, GPI 6150 reduces the degree of colitis caused by dinitrobenzensulfonic acid. We propose that GPI 6150 may be useful in the treatment of inflammatory bowel disease. Topics: Animals; Benzenesulfonates; Benzopyrans; Body Weight; Colitis; Colon; Cytokines; Drug Interactions; Isoquinolines; Male; Neutrophil Infiltration; Peroxidase; Poly Adenosine Diphosphate Ribose; Poly(ADP-ribose) Polymerase Inhibitors; Rats; Rats, Sprague-Dawley | 2002 |
Overexpression of alpha(1)-acid glycoprotein in transgenic mice leads to sensitisation to acute colitis.
alpha(1)-Acid glycoprotein (alpha(1)-AGP) is an acute phase protein in most mammalian species whose concentration rises 2-5-fold during an acute phase reaction. Its serum concentration has often been used as a marker of disease, including inflammatory bowel disease (IBD). High alpha(1)-AGP levels were found to have a prognostic value for an increased risk of relapse in IBD.. To investigate a possible role for increased serum levels of alpha(1)-AGP in the development of IBD.. Dextran sodium sulphate (DSS) 2% was added to the drinking water of transgenic mice, overexpressing the rat alpha(1)-AGP gene, to induce acute colitis, thus mimicking the conditions of relapse. Clinical parameters, inflammatory parameters, and histological analyses on colon sections were performed.. Homozygous alpha(1)-AGP-transgenic mice started losing weight and showed rectal bleeding significantly earlier than heterozygous transgenic or wild-type mice. Survival time of homozygous transgenic mice was significantly shorter compared with heterozygous and wild-type mice. The higher susceptibility of homozygous alpha(1)-AGP-transgenic mice to DSS induced acute colitis was also reflected in higher local myeloperoxidase levels, higher inflammation scores of the colon, and higher systemic levels of interleukin 6 and serum amyloid P component. Local inflammatory parameters were also significantly different in heterozygous transgenic mice compared with wild-type mice, indicating a local dosage effect. In homozygous transgenic mice, significantly higher amounts of bacteria were found in organs but IgA levels were only slightly lower than those of control mice.. Sufficiently high serum levels of alpha(1)-AGP result in a more aggressive development of acute colitis. Topics: Acute Disease; Animals; Colitis; Colony Count, Microbial; Dextran Sulfate; Disease Models, Animal; Female; Gastrointestinal Hemorrhage; Immunoglobulin A; Interleukin-6; Mice; Mice, Inbred C57BL; Mice, Transgenic; Orosomucoid; Peroxidase; Serum Amyloid P-Component; Weight Loss | 2002 |
Endothelin in human inflammatory bowel disease: comparison to rat trinitrobenzenesulphonic acid-induced colitis.
There have been suggestions that endothelins (ET-1, ET-2, ET-3) are involved in the pathogenesis of human inflammatory bowel disease (IBD). Furthermore, the non-selective endothelin receptor antagonist, bosentan, ameliorates colonic inflammation in TNBS colitis in rats. However, no studies have measured the tissue expression and release of endothelins in human IBD in direct comparison to experimental TNBS colitis. Mucosal biopsies were obtained from 114 patients (42 Crohn's colitis, 35 ulcerative colitis and 37 normal) and compared to whole colonic segments from rats with TNBS colitis. ET-1/2 levels were reduced in human IBD but greatly increased in experimental TNBS colitis. RT-PCR indicated ET-2 was the predominant endothelin isoform in human IBD whereas ET-1 prevailed in the TNBS model. No associations were found between human IBD and tissue expression, content or release of ET-1/2. Our study shows, therefore, that unlike TNBS colitis in rats, in which ET-1/2 levels are greatly elevated and ET receptor antagonists are efficacious, there is no significant link between endothelins and human IBD. Topics: Animals; Colitis; Dinoprostone; Endothelin-1; Endothelin-2; Endothelins; Humans; Inflammatory Bowel Diseases; Intestinal Mucosa; L-Lactate Dehydrogenase; Male; Peroxidase; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2002 |
Could honey have a place in colitis therapy? Effects of honey, prednisolone, and disulfiram on inflammation, nitric oxide, and free radical formation.
The purpose of this study was to investigate the potential therapeutic roles of honey, prednisolone and disulfiram in an experimental model of inflammatory bowel disease. Another aspect of the study was to find out whether these substances have any effect on nitric oxide (NO) and free radical production.. After the induction of colitis with trinitrobenzene sulfonic acid in 64 male rats, physiological saline, honey, prednisolone and disulfiram enemas were applied to the rats once daily for 3 days (acute treatment groups) or 7 days (chronic treatment groups). Control groups received only saline enemas. Rats were killed on the 4th or 8th days and their colonic mucosal damage was quantitated using a scoring system. Acute and chronic inflammatory responses were determined by a mucosal injury score, histological examination and measurement of the myeloperoxidase (MPO) activity of tissues. The content of malonylaldehyde (MDA) and NO metabolites in colon homogenates was also measured to assess the effects of these substances on NO and free oxygen radical production.. Estimation of colonic damage by mucosal injury scoring was found to be strongly correlated with the histologic evaluation of colon specimens. On the other hand, mucosal injury scores were not correlated with MPO, MDA or NO values. There were significant differences between the MPO results of chronic-control and chronic-honey groups, as well as chronic-control and chronic-prednisolone groups (p = 0.03 and p = 0.0007). The acute honey, prednisolone, and disulfiram groups had significantly lower MDA results compared to the acute control group (p = 0.04, p = 0.02, and p = 0.04). In terms of NO, there was no significant difference between the treatment and control groups. NO was found to have a strong relationship with MDA (p = 0.03) and MPO values (p = 0.001). On the other hand, MPO results were not found to be correlated with MDA values (p > 0.05).. MPO activity is not directly proportional to the severity of the inflammation, but it may only determine the amount of neutrophil in the tissues. Inflammatory cells are not the sole intensifying factor in colitis. Therefore, mucosal injury scores may not correlate well with MPO activities. In an inflammatory state NO and MPO levels have a strong relationship, since NO is released from the neutrophils. In an inflammatory model of colitis, intrarectal honey administration is as effective as prednisolone treatment. Honey may have some features in the treatment of colitis, but this issue requires further investigation. Honey, prednisolone and even disulfiram also have some value in preventing the formation of free radicals released from the inflamed tissues. Prednisolone may also have some possible benefits in the inhibition of NO production in colitis therapy. Topics: Animals; Anti-Inflammatory Agents; Colitis; Disease Models, Animal; Disulfiram; Enzyme Inhibitors; Honey; Male; Nitric Oxide; Peroxidase; Prednisolone; Rats; Rats, Wistar; Reactive Oxygen Species; Trinitrobenzenesulfonic Acid | 2002 |
Intestinal nematode infection ameliorates experimental colitis in mice.
Epidemiological studies suggest that inflammatory bowel disease (IBD) is common in developed countries and rare in countries where intestinal nematode infections are common. T cells are critical in many immune responses, including those associated with IBD and nematode infection. Among the distinct T helper (Th) cell subsets, Th1-type immune response is predominantly associated with Crohn's disease, while many nematode infections generate a strong Th2 response. The reciprocal cross regulation between Th1 and Th2 cells suggests that generation of a Th2 response by nematodes could prevent or reduce the effects of Th1-mediated diseases. In the present study, we investigated the effect of polarizing the immune response toward the Th2 type, using intestinal nematode infection, on subsequent experimental colitis. Mice were infected with the intestinal nematode Trichinella spiralis and allowed to recover before colitis was induced with dinitrobenzene sulfonic acid. The mice were sacrificed postcolitis to assess colonic damage macroscopically, histologically, and by myeloperoxidase (MPO) activity and Th cytokines. Prior nematode infection reduced the severity of colitis both macroscopically and histologically together with a decreased mortality and was correlated with a down-regulation of MPO activity, Th1-type cytokine expression in colonic tissue, and emergence of a Th2-type immune response. These results indicate a protective role of nematode infection in Th1 cell-driven inflammation and prompt consideration of a novel therapeutic strategy in IBD based on immunological distraction. Topics: Animals; Benzenesulfonates; Colitis; Colon; Inflammatory Bowel Diseases; Interferon-gamma; Interleukin-12; Intestinal Diseases, Parasitic; Mice; Mice, Inbred C57BL; Peroxidase; Th2 Cells; Trichinella spiralis; Trichinellosis | 2002 |
Inflammation inhibits muscarinic signaling in in vivo canine colonic circular smooth muscle cells.
We investigated the effects of experimental colitis on the muscarinic signaling properties and contractile behavior of canine colonic circular smooth muscle. The hypotheses that inflammation 1) inhibits in vivo muscarinic receptor mediated contractions, and 2) alters receptor density or receptor-binding affinities were tested. Muscarine was infused close-intra-arterially in seven conscious dogs during normal and experimental colitis states. Colonic circular muscle contractions were recorded via surgically attached strain gauge transducers. Muscarine stimulated phasic contractions in a dose-dependent manner, whereas colitis was inhibited. The inhibitory concentration 50% dose of M(3) receptor inhibitor was several times lower than that of M(1), M(2), and M(4) inhibitors during normal and colitis. However, inflammation induced a significant leftward shift in the circular muscle inhibitory dose-response curve of M(2) inhibitor. Muscarinic receptor density and binding analyses in isolated circular muscle cells was done in normal and colitis states. Inflammation significantly decreased maximum binding from 4082 fmol/mg to 2708 fmol/mg, whereas affinity constant remained unaffected. The conclusions were that 1) spontaneous and muscarine-activated in vivo phasic contractile activity of colonic circular muscle cells is primarily mediated by M(3) receptors; 2) inflammation was associated with a shift in M(2) receptor potency, due chiefly to a decrease in receptor density; and 3) this inhibitory effect was seen in normal and inflamed states, suggesting the importance of M(2) receptor. These findings suggest that changes in muscarinic response during colitis may contribute to the abnormal motility seen with inflammatory bowel disease. Topics: Animals; Cholinergic Agents; Colitis; Dogs; Female; Ganglionic Blockers; Hexamethonium; Infusions, Intra-Arterial; Male; Muscarine; Muscarinic Antagonists; Muscle Contraction; Muscle, Smooth; Peroxidase; Receptors, Muscarinic; Tetrodotoxin | 2002 |
Dietary fiber down-regulates colonic tumor necrosis factor alpha and nitric oxide production in trinitrobenzenesulfonic acid-induced colitic rats.
Previous studies have revealed the beneficial effects exerted by dietary fiber in human inflammatory bowel disease, which were associated with an increased production of SCFA in distal colon. The aim of the present study was to elucidate the probable mechanisms involved in the beneficial effects of a fiber-supplemented diet (5% Plantago ovata seeds) in the trinitrobenzenesulfonic acid (TNBS) model of rat colitis, with special attention to its effects on the production of some of the mediators involved in the inflammatory response, such as tumor necrosis factor alpha (TNFalpha) and nitric oxide (NO). Rats were fed the fiber-supplemented diet for 2 wk before TNBS colitis induction and thereafter until colonic evaluation 1 wk later. The results obtained showed that dietary fiber supplementation facilitated recovery from intestinal insult as evidenced both histologically, by a preservation of intestinal cytoarchitecture, and biochemically, by a significant reduction in colonic myeloperoxidase activity and by restoration of colonic glutathione levels. This intestinal anti-inflammatory effect was associated with lower TNFalpha levels and lower NO synthase activity in the inflamed colon, showing significant differences when compared with nontreated colitic rats. Moreover, the intestinal contents from fiber-treated colitic rats showed a significantly higher production of SCFA, mainly butyrate and propionate. We conclude that the increased production of these SCFA may contribute to recovery of damaged colonic mucosa because they constitute substrates for the colonocyte and, additionally, that they can inhibit the production of proinflammatory mediators, such as TNFalpha and NO. Topics: Adenocarcinoma; Animals; Butyric Acid; Colitis; Colon; Colonic Neoplasms; Dietary Fiber; Female; Glutathione; Humans; Interleukin-8; Intestinal Mucosa; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Propionates; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha | 2002 |
Oral administration of lactoferrin reduces colitis in rats via modulation of the immune system and correction of cytokine imbalance.
The natural immunomodulator, lactoferrin, is widespread among various biological fluids and is known to exert an anti-inflammatory effect. However, there has been only one study that examined the mode of action of lactoferrin in reducing intestinal damage. We investigated the therapeutic role of lactoferrin and its effect on the levels of pro-inflammatory and anti-inflammatory cytokines, by using a rat model of dextran sulfate sodium (DSS) induced-colitis.. Male Sprague-Dawley rats were given distilled drinking water containing 2.5% (wt/vol) synthetic DSS ad libitum. Bovine lactoferrin was given once daily through gavage, starting 3 days before beginning the DSS administration, until death. The whole colon was removed to be examined macroscopically and histologically. Myeloperoxidase activity, and pro-inflammatory and anti-inflammatory cytokines in the colonic tissue were also measured.. Dextran sulfate sodium-induced colitis was attenuated by oral administration of lactoferrin in a dose-dependent manner, as reflected by improvement in clinical disease activity index, white blood cell count and hemoglobin concentration, macroscopic and histological scores, and myeloperoxidase activity. Reduced inflammation in response to lactoferrin was correlated with the significant induction of the anti-inflammatory cytokines, interleukin-4 and interleukin-10, and with significant reductions in the pro-inflammatory cytokines, tumor necrosis factor alpha, interleukin-1beta, and interleukin-6.. We concluded that oral administration of lactoferrin exerts a protective effect against the development of colitis in rats via modulation of the immune system and correction of cytokine imbalance. Lactoferrin has potential as a new therapeutic agent for inflammatory bowel disease. Topics: Administration, Oral; Animals; Cattle; Colitis; Colon; Cytokines; Dextran Sulfate; Dose-Response Relationship, Drug; Lactoferrin; Male; Peroxidase; Rats; Rats, Sprague-Dawley | 2002 |
NCX-1015, a nitric-oxide derivative of prednisolone, enhances regulatory T cells in the lamina propria and protects against 2,4,6-trinitrobenzene sulfonic acid-induced colitis in mice.
NCX-1015 is a nitric oxide (NO)-releasing derivative of prednisolone. In this study we show NCX-1015 protects mice against the S. A. development and induces healing of T helper cell type 1-mediated experimental colitis induced by intrarectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS). The beneficial effect of NCX-1015 was reflected in increased survival rates, improvement of macroscopic and histologic scores, a decrease in the mucosal content of T helper cell type 1 cytokines (protein and mRNA), and diminished myeloperoxidase activity in the colon. In contrast to its NO derivative, only very high doses of prednisolone were effective in reproducing these beneficial effects. NCX-1015 was 10- to 20-fold more potent than the parent compound in inhibiting IFN-gamma secretion by lamina propria mononuclear cells. Protection against developing colitis correlated with inhibition of nuclear translocation of p65Rel A in these cells. In vivo treatment with NCX-1015 potently stimulated IL-10 production, suggesting that the NO steroid induces a regulatory subset of T cells that negatively modulates intestinal inflammation. Topics: Active Transport, Cell Nucleus; Animals; Anti-Inflammatory Agents; Colitis; Drug Evaluation, Preclinical; Endothelium, Vascular; Interferon-gamma; Interleukin-10; Intestinal Mucosa; Lymphokines; Male; Mesentery; Mice; Mice, Inbred BALB C; Models, Animal; Neutrophils; NF-kappa B; Peroxidase; Prednisolone; T-Lymphocyte Subsets; Transcription Factor RelA; Trinitrobenzenesulfonic Acid | 2002 |
Collagen-binding integrin alpha1beta1 regulates intestinal inflammation in experimental colitis.
Central to inflammatory responses are the integrin-mediated adhesive interactions of cells with their ECM-rich environment. We investigated the role of the collagen-binding integrin alpha(1)beta(1) in intestinal inflammation using the mouse model of colitis induced by dextran sodium sulfate (DSS). mAb's directed against murine alpha(1) were found to significantly attenuate inflammation and injury in DSS-treated wild-type mice; similar protection was seen in mice deficient for alpha(1)beta(1) integrin. Blockade or loss of alpha(1)beta(1) was also associated with decreased mucosal inflammatory cell infiltrate and cytokine production. Importantly, we demonstrated that development and alpha(1)-mediated inhibition of DSS-induced colitis occurred independently of lymphocytes (Rag-2(-/-) mice), and identified the monocyte as a key alpha(1)beta(1)-expressing cell type involved in the development of colitis in this model. In response to DSS, both alpha(1) deficiency and anti-alpha(1) mAb treatment significantly reduced monocyte accumulation and activation within the lamina propria. In summary, the data demonstrate that engagement of leukocyte-associated alpha(1)beta(1) receptors with ECM plays a pivotal role in mediating intestinal inflammation via promotion of monocyte movement and/or activation within the inflamed interstitium. Therapeutic strategies designed to disrupt such interactions may prove beneficial in treating intestinal inflammation. Topics: Animals; Antibodies, Monoclonal; CD11b Antigen; Colitis; Collagen; Cytokines; Dextran Sulfate; Disease Models, Animal; DNA-Binding Proteins; Humans; Immunohistochemistry; Indicators and Reagents; Integrin alpha1beta1; Intestinal Mucosa; Intestines; Lymphocytes; Male; Mice; Mice, Inbred BALB C; Mice, Knockout; Monocytes; Nuclear Proteins; Peroxidase; Protein Binding | 2002 |
Cyclooxygenase-2 inhibition and experimental colitis: beneficial effects of phosphorothioated antisense oligonucleotide and meloxicam.
The effects of cyclooxygenase-2 (cox-2) inhibition by a cox-2 selective antisense phosphorothioated oligonucleotide (AS) and meloxicam were examined in experimental colitis.. Colitis was induced by trinitrobenzenesulphonic acid (TNBS) and acetic acid (Hac) separately in male Sprague-Dawley rats. Both groups of animals were treated daily intraperitoneally with AS and a mismatched control oligo (CO) (3 mg/kg), and orally with meloxicam (7.5 mg/kg) 1 h before induction of colitis. The animals were killed on day 4 (Hac) and on day 5 (TNBS). Tissue samples from colon, ileum, liver, kidney and spleen were collected for mRNA, myeloperoxidase activity (MPO), prostaglandin E2 (PGE2) estimation and for histology, and blood samples for PGE2, thromboxane B2 (TxB2) and TNF-alpha.. Both TNBS and Hac increased colonic MPO activity, PGE2 concentrations and infiltration of colonic wall by inflammatory cells. Serum levels of TNF-alpha were increased in both models, whereas PGE2 was increased only in TNBS colitis. Only meloxicam suppressed the level of PGE2 significantly below the basal level. The animals in both models also showed splenomegaly. The colitis-induced changes were significantly suppressed by the treatment of the test compounds but not by the CO. Cox-2 mRNA but not cox-1 was decreased by the AS, but not by meloxicam or in CO-treated colitic animals.. The findings demonstrate comparable beneficial effects of the cox-2 selective antisense oligonucleotide and meloxicam, which seem to be mediated by a combined inhibition of both PGE2 and TNF-alpha in the present models of colitis. Topics: Animals; Colitis; Colon; Cyclooxygenase Inhibitors; Dinoprostone; Male; Meloxicam; Oligonucleotides, Antisense; Peroxidase; Polymerase Chain Reaction; Rats; Rats, Sprague-Dawley; RNA, Messenger; Thiazines; Thiazoles; Thromboxane B2; Tumor Necrosis Factor-alpha | 2002 |
Inhibition of intestinal bacterial translocation with rifaximin modulates lamina propria monocytic cells reactivity and protects against inflammation in a rodent model of colitis.
A modification of the intestinal flora and an increased bacterial translocation is a common finding in patients with inflammatory bowel disease as well as in animal model of colitis. Rifaximin, a non-absorbable derivative of rifamycin, is an effective antibiotic that acts by inhibiting bacterial ribonucleic acid synthesis.. In the present study, we investigated the effect of the administration of rifaximin (10, 30 and 50 mg/kg/day) or prednisolone (10 mg/kg/day) in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice.. Colitis was induced in mice by intrarectal administration of TNBS (1.5 mg/mouse in 50% ethanol) and disease severity assessed clinically and by histologic scoring of colon damage, determination of interleukin (IL)-2, IL-12, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha (protein and mRNA and myeloperoxidase (MPO) activity in the colon. Cytokines production by the lamina propria mononuclear cells (LPMC) and luminal bacteria were also measured.. Rifaximin administration (30 or 50 mg/kg/day) increased survival rates of colitic mice and reduced colitis severity as demonstrated by improvement of wasting syndrome, histologic scores, decrease in colon IL-2, IL-12, IFN-gamma and TNF-alpha (protein and mRNA) levels, and diminished colon MPO activity. Rifaximin administration caused a significant reduction of colon bacterial translocation towards mesenteric lymph nodes. LPMC obtained from rifaximin-treated mice released significantly lower amount of IFN-gamma in response to ex vivo stimulation with agonistic anti-CD3 and anti-CD28 antibodies. Rifaximin (50 mg/kg/day) significantly accelerates recovery in mice with established colitis.. Luminal bacterial microflora plays a role in the pathogenesis of TNBS-induced colitis in mice. Rifaximin administration reduces the development of colitis and accelerates healing of established disease by preventing bacterial translocation. Topics: Acute Disease; Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents; Bacterial Translocation; Colitis; Colon; Cytokines; Dose-Response Relationship, Drug; Interferon-gamma; Intestinal Mucosa; Leukocytes, Mononuclear; Lymph Nodes; Mesentery; Mice; Mice, Inbred BALB C; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Prednisolone; Rifamycins; Rifaximin; Trinitrobenzenesulfonic Acid | 2002 |
Hyperbaric oxygen improves healing in experimental rat colitis.
This study was designed to investigate therapeutic effects of hyperbaric oxygen on experimentally induced colitis in rats by assessing oxidative tissue damage, neutrophil accumulation and histological changes. Six groups of animals were used. No procedures were done in the sham group. In the vehicle group, 50% ethanol-induced colitis, and in four other groups, 2,4,6-trinitrobenzene sulphonic acid-induced colonic inflammation was achieved. In acute and chronic colitis non-treatment groups, no other procedure was done. In acute and chronic colitis hyperbaric oxygen treatment groups, rats underwent hyperbaric oxygen treatment for two or fourteen days. On the third and fifteenth days respectively tissue and blood samples were taken for microscopic and macroscopic damage assessment, myeloperoxidase activity and serum carbonyl content measurements. There was significant colonic tissue damage in non-treatment groups at 48 hours and 14 days. Hyperbaric oxygen treatment ameliorated the macroscopic damage significantly in chronic colitis. Amelioration of microscopic changes was not significant in each hyperbaric oxygen-treated group. Hyperbaric oxygen treatment significantly reduced tissue myeloperoxidase activity in acute colitis and decreased plasma carbonyl content in chronic colitis. In the present study, hyperbaric oxygen treatment significantly ameliorated trinitrobenzene sulphonic acid-induced chronic colitis in rats. Topics: Analysis of Variance; Animals; Colitis; Colon; Hyperbaric Oxygenation; Male; Oxidation-Reduction; Peroxidase; Proteins; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2002 |
Anti-inflammatory effect of kaurenoic acid, a diterpene from Copaifera langsdorffi on acetic acid-induced colitis in rats.
Kaurenoic acid, a diterpene from Copaifera langsdorffii (Leguminaceae), was evaluated on rat colitis induced by acetic acid. Rats were pretreated orally (15 and 2 h before) or rectally 2 h before induction of colitis with kaurenoic acid (50 and 100 mg/kg) or vehicle (1 ml, 3% DMSO). Colitis was induced by intracolonic instillation of a 2 ml of 4% (v/v) acetic acid solution and, 24 h later, the colonic mucosal damage was analysed macroscopically for the severity of mucosal damage, the myeloperoxidase (MPO) activity and the malondialdehyde (MDA) levels in the colon segments. A marked reduction in gross damage score (52% and 42%) and wet weight of damaged colon tissue (39% and 32%) were observed in rats that received 100 mg/kg kaurenoic acid, respectively, by rectal and oral routes. This effect was confirmed biochemically by a two- to three-fold reduction of colitis associated increase in MPO activity, the marker of neutrophilic infiltration and by a marked decrease in MDA level, an indicator of lipoperoxidation in colon tissue. Furthermore, light microscopy revealed the marked diminution of inflammatory cell infiltration and submucosal edema formation in the colon segments of rats treated with the test compound. These findings indicate the anti-inflammatory potential of kaurenoic acid in acetic acid-induced colitis. Topics: Acetic Acid; Administration, Oral; Administration, Rectal; Animals; Anti-Inflammatory Agents, Non-Steroidal; Brazil; Colitis; Diterpenes; Fabaceae; Intestinal Mucosa; Male; Malondialdehyde; NF-kappa B; Peroxidase; Rats; Rats, Wistar | 2002 |
Prostaglandin E2 and reactive oxygen metabolite damage in the cecum in a pony model of acute colitis.
The objective of this project was to determine early tissue biochemical events associated with increased colonic secretion during the acute stage of castor-oil-induced colitis by measuring cecal mucosal and submucosal malondialdehyde (MDA) and prostaglandin E2 (PGE2), levels in ponies. Intestinal tissue (inflamed or healthy) samples were obtained from 4 age- and sex-matched Shetland ponies. Biochemical methods were used to determine MDA and PGE2 levels in intestinal tissue samples from inflamed and healthy equine intestine. Inflamed tissue MDA and PGE2 levels increased with time after castor oil challenge and correlated with granulocyte infiltration, as determined by myeloperoxidase levels in a companion study. Elevated intestinal tissue MDA levels suggest that lipid peroxidation could be attributed to reactive oxygen metabolites (ROM) released from stimulated, recruited, and resident granulocytes. Tissue levels of MDA and PGE2 suggest a role for granulocyte-derived mediators of intestinal inflammation in the massive secretory response in cases of acute equine colitis. Tissue MDA and PGE2 levels may be useful laboratory tools to quantify and characterize intestinal secretory inflammatory responses in acute inflammatory conditions in the equine colon. Topics: Acute Disease; Animals; Castor Oil; Cecum; Colitis; Dinoprostone; Disease Models, Animal; Female; Granulocytes; Horse Diseases; Horses; Inflammation; Intestinal Mucosa; Lipid Peroxidation; Male; Malondialdehyde; Peroxidase; Reactive Oxygen Species | 2002 |
Effect of heparin on tissue binding activity of fibroblast growth factor and heparin-binding epidermal growth factor in experimental colitis in rats.
There have been several reports implying a benefit for heparin therapy in patients with refractory ulcerative colitis. Although this effect has been attributed to the anti-inflammatory properties of heparin, other mechanisms have not been excluded. Heparin is a potent modulator of receptor binding of growth factors such as fibroblast growth factor (FGF), vascular endothelial growth factor, and heparin-binding epidermal growth factor (HB-EGF), that play a role in wound repair. We examined the effect of heparin on the functional levels of FGF and HB-EGF in a model of experimental colitis. Fifty-six Wistar rats were divided into four groups: group 1 was the control group, group 2 received s.c. heparin 50 units/kg/d, group 3 underwent induction of 3% iodoacetamide colitis, and group 4 underwent induction of colitis and heparin treatment. Rats were killed and evaluated for severity of colitis by macroscopic and microscopic colitis scores, area of inflammation, and myeloperoxidase levels. FGF and HB-EGF levels were functionally assessed in colonic tissue in each group. Heparin therapy resulted in significant improvement in macroscopic and microscopic features of colitis (p < 0.05), accompanied by a partial reduction in myeloperoxidase levels. FGF receptor binding activity was identical in groups 1 and 2 but increased more than 3-fold after colitis induction in group 3 (p < 0.05). Treatment with heparin caused a significant decrease in FGF concentration. Levels of HB-EGF binding activity were similar in groups 1 and 2 and decreased in group 3 (p < 0.01). Heparin caused a significant increase in HB-EGF content in group 4 (p < 0.05). Levels of growth factors are altered differently in experimental colitis. Colonic FGF binding activity increases with colitis, whereas HB-EGF binding decreases with colitis. These trends were reversed by heparin, concomitant with a clinical and pathologic improvement in colitis. We suggest that one mechanism of heparin-mediated improvement in colitis may involve tissue healing associated with changes in functional levels of colonic growth factors. Topics: Animals; Colitis; Drug Evaluation, Preclinical; Epidermal Growth Factor; Fibroblast Growth Factors; Heparin; Heparin-binding EGF-like Growth Factor; Intercellular Signaling Peptides and Proteins; Intestinal Mucosa; Iodoacetamide; Male; Peroxidase; Protein Binding; Rats; Rats, Wistar | 2002 |
Nitric oxide supplementation ameliorates dextran sulfate sodium-induced colitis in mice.
Nitric oxide (NO) synthesis is up-regulated in inflammatory bowel disease. However, its role in the pathophysiology of this condition is controversial. The aims of this study were to assess whether nitric oxide administration ameliorates experimental colitis and to determine the possible mechanisms underlying its effects on intestinal inflammation. For this purpose, the NO donor diethylamine NONOate (DETA/NO; 0.01, 0.1, 1, 5, or 10 mg/kg/day), or the DETA moiety, was administered daily to mice with dextran sulfate sodium-induced colitis. Daily body weight and colonic pathologic alterations at Day 10 were determined. Leukocyte endothelial cell interactions in colonic venules were assessed with intravital microscopy, and expression of endothelial cell adhesion molecules was determined using radiolabeled antibodies. IL-12 and IFN-gamma production were measured in intestinal tissue. Colitis induced a significant loss of body weight, reduction of colon length, and increase in colon weight and myeloperoxidase activity. Administration of 1 mg/kg/day DETA/NO significantly attenuated these pathologic changes. The marked increase in leukocyte rolling and adhesion in colonic venules of colitic mice were significantly reduced by administration of 1 mg/kg/day DETA/NO. Development of colitis was associated with a marked increase in endothelial expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and P-selectin. Supplementation with NO significantly attenuated the up-regulation of endothelial intercellular adhesion molecule-1 and P-selectin, but not vascular cell adhesion molecule-1, in colonic tissue. NO abrogated the increase in IL-12 and IFN-gamma mRNA expression in the colon of colitic mice. The DETA moiety alone did not have any effect on any of the parameters studied. In conclusion, exogenous NO supplementation significantly ameliorates dextran sulfate sodium-induced colitis. This effect is related to a reduction in leukocyte recruitment and proinflammatory cytokine production. Topics: Animals; Body Weight; Cell Adhesion; Cell Adhesion Molecules; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Epithelium; Hydrazines; Interferon-gamma; Interleukin-12; Leukocytes; Male; Mice; Mice, Inbred Strains; Nitric Oxide Donors; Nitrogen Oxides; Peroxidase; RNA, Messenger; Venules | 2002 |
Antisense inhibition of cyclooxygenase-2 causes a selective suppression of the Na+-H+ exchanger isoform 3 in rat kidney in experimental colitis.
Experimental colitis induces the expression of Na+-H+ exchanger (NHE) isoforms 1 and 3 in the rat colon, however, their status in rat kidney is not established.. The renal cortical NHE-1 and -3 expression was examined in the colitic rats. Since cyclooxygenase-2 (cox-2) plays an important role in inflammation, its regulatory role on these isoforms was also investigated by using a cox-2-selective phosphorothioated antisense oligonucleotide (S-oligo).. Male Sprague-Dawley rats having colitis induced by acetic acid or trinitrobenzenesulfonic acid (TNBS) were given injection of S-oligo (3 mg/kg, i.p.) and a mismatched control oligonucleotide (C-oligo) daily 2 h before inducing colitis. Colonic myeloperoxidase activity (MPO) was used to indicate colitis. The renal cortical levels of NHE-1, NHE-3 and alpha-actin, an internal control, were estimated by the Western blot analysis.. Colonic MPO activity was increased and urine output was decreased in both models of colitis. Serum, but not the renal cortical level of TNF-alpha, was increased in both cases. Only TNBS condition showed an increased PGE2 level and a decreased body weight. Water intake and renal histology remained unchanged in either case. The NHE-3 protein, localized on the proximal tubules, was increased significantly without any change in NHE-1 and alpha-actin in both cases. These changes, except the body weight, were significantly reversed by the S-oligo.. Selective induction of NHE-3 and TNF-alpha, and their reversal by cox-2 inhibition, suggest a cox-2-dependent regulation of NHE-3, which possibly involves TNF-alpha released from the site of inflammation and not from the kidney in colitis. The induction of NHE-3 is independent of the nature of colitides, and might be important to compensate for the loss of electrolyte and water in experimental colitis. Topics: Acetic Acid; Animals; Antibody Specificity; Blotting, Western; Body Weight; Colitis; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Dinoprostone; Isoenzymes; Male; Microsomes; Oligonucleotides, Antisense; Peroxidase; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Sprague-Dawley; Sodium-Hydrogen Exchangers; Tumor Necrosis Factor-alpha; Urodynamics | 2002 |
Effect of zinc supplementation on intestinal permeability in experimental colitis.
Increased small-intestine permeability has been documented in experimental colitis in the rat. Zinc supplementation improves mucosal repair in patients with diarrhea, as well as paracellular permeability in malnourished guinea pigs. In this study, we sought to evaluate the effect of zinc supplementation on small-and large-intestine tight junctions in rats with acute colitis. Rats were given zinc at a dosage of 2 or 30 mg/kg body wt or glucose by gavage starting 3 days before colitis was induced through the intrarectal administration of dinitro-benzene-sulfonic acid and for 7 days thereafter. We evaluated small-intestine permeability by the number of tight junctions showing extravasation of lanthanum under electron microscopy. Low-dose zinc affected none of the examined parameters of colitis severity. Rats given high-dose zinc showed colitis of similar macroscopic and biochemical severity. However, zinc-treated rats weighed more than unsupplemented ones. The number of perfused tight-junction complexes was significantly higher in animals with colitis than in controls and in the rats with colitis given high-dose zinc. Zinc may regulate tight-junction permeability, with possible implications for healing processes in inflammatory bowel diseases. Topics: Animals; Colitis; Dietary Supplements; Dinitrofluorobenzene; Intestinal Absorption; Intestinal Mucosa; Intestine, Large; Intestine, Small; Lanthanum; Male; Microscopy, Electron; Peroxidase; Rats; Rats, Sprague-Dawley; Tight Junctions; Zinc | 2002 |
Protective effect of low molecular weight heparin on experimental colitis: role of neutrophil recruitment and TNF-alpha production.
The purpose of this study was to examine the impact and mechanism of action of low molecular weight heparin (LMWH) in a model of murine colitis.. Balb/c mice were exposed to 5% dextran sodium sulfate (DSS) in the drinking water for five days. LMWH (500 units/kg/day) was administered by subcutaneous injection prior to and throughout the treatment period with DSS. Clinical disease activity index (DAI), including body weight loss, stool consistency and blood in feces were examined daily. Moreover, crypt height (CH), mucosal damage score (MDS), myeloperoxidase (MPO) activity and tumor necrosis factor-alpha (TNF-alpha) content in the colon were determined.. DSS increased DAI, MDS, MPO activity and TNF-alpha production and decreased CH. Administration of LMWH markedly reduced DAI, MDS and reversed the CH-reduction. Moreover, in LMWH-treated animals, the MPO activity was reduced by more than 67% whereas mucosal levels of TNF-alpha was similar compared to DSS control mice.. These findings suggest that LMWH inhibits murine colitis by interference with neutrophil recruitment and that LMWH may provide a novel pharmacological approach to treatment of inflammatory bowel disease. Topics: Animals; Anticoagulants; Colitis; Dextran Sulfate; Enzyme-Linked Immunosorbent Assay; Heparin, Low-Molecular-Weight; Intestinal Mucosa; Male; Mice; Mice, Inbred BALB C; Neutrophils; Peroxidase; Tumor Necrosis Factor-alpha | 2002 |
Modulatory effects of estrogen in two murine models of experimental colitis.
The association between oral contraceptives or pregnancy and inflammatory bowel disease is unclear. We investigated whether 17beta-estradiol modulates intestinal inflammation in two models of colitis. Female mice were treated with 17beta-estradiol alone or with tamoxifen, tamoxifen alone, 17 alpha-estradiol, or placebo. Dinitrobenzene sulfonic acid (DNB)- or dextran sodium sulfate (DSS)-induced colitis were assessed macroscopically, histologically, and by myeloperoxidase (MPO) activity. Malondialdehyde and mRNA levels of intercellular adhesion molecule-1 (ICAM-1), interferon-gamma (IFN-gamma), and interleukin-13 (IL-13) were determined. In DNB colitis, 17beta-estradiol alone, but not 17beta-estradiol plus tamoxifen, or 17 alpha-estradiol reduced macroscopic and histological scores, MPO activity and malondialdehyde levels. 17beta-Estradiol also decreased the expression of ICAM-1, IFN-gamma, and IL-13 mRNA levels compared with placebo. In contrast, 17beta-Estradiol increased the macroscopic and histological scores compared with placebo in mice with DSS colitis. These results demonstrate anti-inflammatory and proinflammatory effects of 17beta-estradiol in two different models of experimental colitis. The net modulatory effect most likely reflects a combination of estrogen receptor-mediated effects and antioxidant activity and may explain, in part, conflicting results from clinical trials. Topics: Animals; Benzenesulfonates; Body Weight; Colitis; Dextran Sulfate; Drug Administration Schedule; Estradiol; Female; Intercellular Adhesion Molecule-1; Interferon-gamma; Interleukin-13; Macrophage Colony-Stimulating Factor; Mice; Mice, Inbred C57BL; Peroxidase; RNA, Messenger; Tamoxifen; Tumor Necrosis Factor-alpha | 2002 |
Expression of the EP4 prostaglandin E2 receptor subtype with rat dextran sodium sulphate colitis: colitis suppression by a selective agonist, ONO-AE1-329.
Expression of the EP4 receptor, a prostaglandin (PG)E2 receptor subtype, as well as disease suppression by the administration of a selective EP4 agonist (ONO-AE1-329) was investigated in the colorectal mucosa of rats with dextran sodium sulphate (DSS)-induced colitis. Rats were given drinking water containing 3% DSS for 2 weeks. Expression of EP4 receptor mRNA was barely detectable under normal conditions according to reverse transcription-polymerase chain reaction (RT-PCR). By 1 week after the initial administration of DSS, the receptor mRNA was strongly expressed. After ONO-AE1-329 was administered intracolonically to rats with DSS colitis for 7 consecutive days, erosion and ulceration decreased. Peripheral white blood cell (WBC) counts became less elevated. Interleukin (IL)-1beta and growth-regulated gene product/cytokine-induced neutrophil chemoattractant (GRO/CINC-1) concentrations in colorectal mucosa were lower than in colitis control group (IL-1beta: 12.8 +/- 4.6 and 30.8 +/- 6.2 microg/mg protein, P < 0.05; GRO/CINC-1: 15.5 +/- 3.0 and 39.2 +/- 5.4 microg/mg protein, P < 0.05), and the expression of the corresponding cytokine mRNA was strongly suppressed. IL-10 concentration was higher than in control group (14.5 +/- 1.7 and 7.9 +/- 1.2 microg/mg, P < 0.05), and the mRNA was more strongly expressed. These results suggest that the EP4 receptor is important in colonic inflammation, and that PGE2 suppresses DSS colitis at least partly via the EP4 receptor and the above cytokine changes. Intracolonic administration of selective EP4 agonist might have therapeutic applicability in inflammatory bowel disease such as ulcerative colitis. Topics: Acute Disease; Animals; Anti-Ulcer Agents; Chemokine CXCL1; Chemokines, CXC; Chemotactic Factors; CHO Cells; Colitis; Colon; Cricetinae; Dextran Sulfate; Dinoprostone; Dose-Response Relationship, Drug; Gene Expression; Growth Substances; Intercellular Signaling Peptides and Proteins; Interleukin-1; Interleukin-10; Leukocyte Count; Male; Methyl Ethers; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Prostaglandin E; Receptors, Prostaglandin E, EP2 Subtype; Receptors, Prostaglandin E, EP4 Subtype; RNA, Messenger; Time Factors | 2002 |
Protective role of cyclooxygenase inhibitors in the adverse action of passive cigarette smoking on the initiation of experimental colitis in rats.
Clinical and experimental findings had indicated that cigarette smoke exposure, and cyclooxygenase-2, are strongly associated with inflammatory bowel disease. The present study aimed to evaluate the role of cyclooxygenase-2 in the pathogenesis of experimental inflammatory bowel disease as well as in the adverse action of cigarette-smoke exposure. Rats were pretreated with different cyclooxygenase-2 inhibitors (indomethacin, nimesulide, or SC-236 (4-[5-(4-chlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide)) along with cigarette-smoke exposure before 2,4,6-trinitrobenzenesulfonic acid-enema. Results indicated that pretreatment with cyclooxygenase-2 inhibitors not only protected against 2,4,6-trinitrobenzenesulfonic acid-induced inflammatory bowel disease, but also attenuated the potentiating effect of cigarette-smoke exposure on colonic damage. Furthermore, the colonic cyclooxygenase-2 protein and mRNA expression was markedly induced by 2,4,6-trinitrobenzenesulfonic acid-enema, and it was potentiated further by cigarette-smoke exposure, while the cyclooxygenase-1 expression was not changed. The present study suggests that the highly induced cyclooxygenase-2 expression not only plays a pathogenic role in 2,4,6-trinitrobenzenesulfonic acid-induced inflammatory bowel disease, but also contributes to the adverse action of cigarette-smoke exposure on this disorder. Topics: Animals; Blotting, Western; Colitis; Colon; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Gene Expression Regulation, Enzymologic; Indomethacin; Inflammation; Inflammatory Bowel Diseases; Isoenzymes; Leukotriene B4; Male; Membrane Proteins; Peroxidase; Prostaglandin-Endoperoxide Synthases; Prostaglandins; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sulfonamides; Tobacco Smoke Pollution; Trinitrobenzenesulfonic Acid | 2001 |
Endogenous PPAR gamma mediates anti-inflammatory activity in murine ischemia-reperfusion injury.
Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a nuclear receptor whose activation has been linked to several physiologic pathways including those related to the regulation of intestinal inflammation. We sought to determine whether PPAR gamma could function as an endogenous anti-inflammatory pathway in a murine model of intestinal ischemia-reperfusion (I/R) injury.. PPAR gamma-deficient and wild-type mice were examined for their response to I/R procedure. Treatment with a PPAR gamma-specific ligand was also performed.. In a murine model of intestinal I/R injury, we observed more severe injury in PPAR gamma-deficient mice and protection against local and remote tissue injury in mice treated with a PPAR gamma-activating ligand, BRL-49653. Activation of PPAR gamma resulted in down-regulation of intercellular adhesion molecule 1 expression by intestinal endothelium and tissue tumor necrosis factor alpha messenger RNA levels most likely by inhibition of the NF-kappa B pathway.. These data strongly suggest that an endogenous PPAR gamma pathway exists in tissues that may be amenable to therapeutic manipulation in I/R-related injuries. Topics: Animals; Cells, Cultured; Colitis; Epithelial Cells; Gastric Mucosa; Gene Expression; Hypoglycemic Agents; In Vitro Techniques; Intercellular Adhesion Molecule-1; Interleukin-8; Intestinal Mucosa; L-Lactate Dehydrogenase; Liver; Mice; Mice, Inbred BALB C; Mice, Knockout; NF-kappa B; Peroxidase; Pneumonia; Receptors, Cytoplasmic and Nuclear; Reperfusion Injury; RNA, Messenger; Rosiglitazone; Stomach; Thiazoles; Thiazolidinediones; Transcription Factors; Tumor Necrosis Factor-alpha | 2001 |
Melatonin reduces dinitrobenzene sulfonic acid-induced colitis.
Inflammatory bowel disease (IBD) is characterized by oxidative and nitrosative stress, leukocyte infiltration, and up-regulation of intercellular adhesion molecule 1 (ICAM-1) expression in the colon. The aim of this study was to examine the effects of the pineal secretory product melatonin in rats subjected to experimental colitis. Colitis was induced in rats by intracolonic instillation of dinitrobenzene sulfonic acid (DNBS). Rats experienced bloody diarrhea and a significant loss of body weight. Four days after DNBS administration, the colon damage was characterized by areas of mucosal necrosis. Neutrophil infiltration (indicated by myeloperoxidase [MPO] activity in the mucosa) was associated with up-regulation of ICAM-1, expression of P-selectin, and high levels of malondialdehyde (MDA). Immunohistochemistry for nitrotyrosine and poly (ADP-ribose) synthetase (PARS) showed an intense staining in the inflamed colon. Staining of colon tissue sections obtained from DNBS-treated rats with an anti-cycloxygenase-2 (COX-2) antibody showed a diffuse staining of the inflamed tissue. Furthermore, expression of inducible nitric oxide synthase (iNOS) was found mainly in the macrophages of the inflamed colons from DNBS-treated rats. Treatment with melatonin (15 mg/kg daily, intraperitoneally) significantly reduced the appearance of diarrhea and the loss of body weight. This was associated with a remarkable amelioration of the disruption of the colonic architecture, as well as a significant reduction of colonic MPO activity and MDA levels. Melatonin also reduced the appearance of nitrotyrosine and PARS immunoreactivity in the colon, as well as reducing the up-regulation of ICAM-1 and the expression of P-selectin. The intensity and degree of the stainings for COX-2 and iNOS were markedly reduced in tissue sections obtained from melatonin-treated rats. The results of the this study suggest that the administration of melatonin might be beneficial for the treatment of IBD. Topics: Animals; Colitis; Colon; Dinitrofluorobenzene; Fluorescent Antibody Technique, Indirect; Free Radical Scavengers; Immunohistochemistry; Intercellular Adhesion Molecule-1; Male; Malondialdehyde; Melatonin; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; P-Selectin; Peroxidase; Poly Adenosine Diphosphate Ribose; Rats; Rats, Sprague-Dawley; Tyrosine | 2001 |
Motilin receptor density in inflamed and noninflamed tissue in rabbit TNBS-induced colitis.
Trinitrobenzenesulphonic acid (TNBS)-induced colitis decreases the contractile response of the rabbit colon to motilin, and inflammation may increase plasma motilin levels. We studied whether the decreased contractility could be due to a down-regulation of motilin receptors, caused by increased plasma motilin levels. As this would affect all tissues, uninflamed sites were studied as well. Colitis was induced by different doses (100-150 mg kg-1) of TNBS. In the colon, the TNBS dose-dependent decrease of the contractile response towards motilin was reflected in a decrease in motilin receptor density. In contrast, in the antrum, receptors were upregulated by 150 mg kg-1 TNBS, while central motilin receptors in the cerebellum were not affected. Plasma motilin levels were not influenced by inflammation, although the motilin content and mRNA expression in the duodenal and jejunal mucosa, but not in the colon, was significantly increased. The opposite was true for interleukin-1beta and interleukin receptor antagonist mRNA expression. We conclude that the decreased motilin contractility in rabbit colitis is due to a downregulation of motilin receptors in the colon, but this is not caused by chronic hormonal stimulation. Topics: Animals; Autoradiography; Colitis; Female; Interleukin-1; Intestinal Mucosa; Male; Muscle Contraction; Peroxidase; Rabbits; Receptors, Gastrointestinal Hormone; Receptors, Interleukin-1; Receptors, Neuropeptide; Trinitrobenzenesulfonic Acid | 2001 |
Estimation of mucosal inflammatory mediators in rat DSS-induced colitis. Possible role of PGE(2) in protection against mucosal damage.
In order to investigate the mucosal injury mechanism in UC, we made dextran sulfate sodium (DSS)-induced colitis in rat and examined pathological findings, MPO activity, PGE(2) level, and local mRNA expression and secretion of IL-1 beta, TNF-alpha, GRO/CINC-1 and IL-10 in DSS colitis mucosa. Moreover, we estimated the correlation between the severity of mucosal damage and changes of these local inflammatory mediators' values. Neutrophil infiltration was marked and MPO activity was locally increased in proportion to the severity of mucosal damage. The mRNA expression and secretion of IL-1 beta, GRO/CINC-1 and IL-10 were increased. Especially, the secretions of IL-1 beta and GRO/CINC-1 were increased in proportion to the severity of mucosal damage. However, those of TNF-alpha were not increased in the colitis mucosa. An abnormal macrophage function and the presence of macrophage subtypes producing different cytokines would be predicted from our TNF-alpha data. The lesion was less severe in the colonic mucosa with higher levels of endogenous PGE(2), while it was more severe in the colonic mucosa with lower levels of endogenous PGE(2), implicating this compound as an inhibitory factor against the development of inflammation in the affected mucosa. Our results suggest that PGE(2) might have therapeutic applicability to UC. Topics: Animals; Anticoagulants; Colitis; Cytokines; Dextran Sulfate; Dinoprostone; Disease Models, Animal; Intestinal Mucosa; Macrophages; Male; Neutrophil Infiltration; Peroxidase; Rats; Rats, Sprague-Dawley; RNA, Messenger; Severity of Illness Index | 2001 |
Role of P-selectin and intercellular adhesion molecule-1 in TNB-induced colitis in rats.
It has been proposed that neutrophil-endothelial cell interactions mediated by adhesion molecules are involved in the pathogenesis of inflammatory bowel disease. The objective of the present study was to determine the effects of monoclonal antibodies (MAbs) directed against endothelial adhesion molecules, P-selectin and intercellular adhesion molecule-1 (ICAM-1), in rats with colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNB). Colonic inflammation was induced by administering an enema of TNB dissolved in 50% ethanol (120 mg/ml) to male Wistar rats (at a total volume of 0.25 ml per rat) after a 48-hour fast. Anti-P-selectin MAb or anti-ICAM-1 MAb was injected via the tail vein at a dose of 1 mg/kg after the induction of colitis. Rats in the control group received nonbinding mouse immunoglobulin G1. The plasma level of soluble P-selectin showed an increase within 48 h after the TNB enema. Colonic inflammation was assessed at 1 week after TNB administration. The colonic damage score and the wet weight of the colon were significantly decreased by treatment with either MAb. The increase of myeloperoxidase (MPO) activity, an index of neutrophil accumulation, and the increase of thiobarbituric acid-reactive substances (TBA-RS), an index of lipid peroxidation, in the colonic mucosa were inhibited by both MAbs. These results suggest that neutrophil-endothelial cell interactions via P-selectin and ICAM-1 play an important role in the development of TNB-induced colitis in rats. Topics: Animals; Antibodies, Monoclonal; Colitis; Endothelium; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Male; Neutrophils; P-Selectin; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2001 |
Different types of contractions in rat colon and their modulation by oxidative stress.
The aim of this study was to investigate the modulation of in vitro rat colonic circular muscle contractions by dextran sodium sulfate (DSS)-induced inflammation and in spontaneous inflammation in HLA-B27 rats. We also examined the potential role of hydrogen peroxide (H(2)O(2)) in modulating excitation-contraction coupling. The muscle strips from the middle colon generated spontaneous phasic contractions and giant contractions (GCs), the proximal colon strips generated primarily phasic contractions, and the distal colon strips were mostly quiescent. The spontaneous phasic contractions and GCs were not affected by inflammation, but the response to ACh was suppressed in DSS-treated rats and in HLA-B27 rats. H(2)O(2) production was increased in the muscularis of the inflamed colon. Incubation of colonic muscle strips with H(2)O(2) suppressed the spontaneous phasic contractions and concentration and time dependently reduced the response to ACh; in the middle colon, it also increased the frequency of GCs. We conclude that H(2)O(2) mimics the suppression of the contractile response to ACh in inflammation. H(2)O(2) also selectively suppresses phasic contractions and increases the frequency of GCs, as found previously in inflamed dog and human colons. Topics: Animals; Animals, Genetically Modified; Colitis; Colon; Dextran Sulfate; Hydrogen Peroxide; In Vitro Techniques; Male; Muscle Contraction; Muscle, Smooth, Vascular; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley | 2001 |
Blood purine and energy status in rats with colitis.
Colitis reduces the blood and tissue levels of adenosine deaminase and adenylate deaminase. Whether this has any effect on blood purines remains to be determined. The aim of this study was to measure the adenylate pool, substrates of the above enzymes, and energy status in blood from rats with colitis. Colitis was induced by intrarectal administration of acetic acid and followed over a period of seven days. The levels of ATP, ADP, AMP, adenosine, inosine, and uric acid were analyzed by HPLC, and energy status was estimated. Myeloperoxidase was used as a marker of colitis. Concentrations of ATP, ADP, AMP and adenosine decreased during days 1-5, whereas energy status decreased on day 2. The concentrations of inosine, uric acid, and hemoglobin remained unaltered, whereas colonic myeloperoxidase activity increased. These, findings demonstrate colitis-induced reduction of the circulating purines, which may be due to their enhanced usage for the repair of the inflamed colon. Topics: Acetic Acid; Adenosine; Adenosine Diphosphate; Adenosine Monophosphate; Adenosine Triphosphate; Animals; Biomarkers; Chromatography, High Pressure Liquid; Colitis; Disease Models, Animal; Energy Metabolism; Hemoglobins; Inosine; Male; Peroxidase; Purines; Rats; Rats, Wistar; Time Factors; Uric Acid | 2001 |
Inhibition of selectin function and leukocyte rolling protects against dextran sodium sulfate-induced murine colitis.
The selectin family of adhesion molecules (P-, E- and L-selectin) plays an important role in inflammatory reactions by mediating interactions between leukocytes and activated endothelial cells. However, a recent study using gene-targeted mice has suggested that adhesion molecules (P- and E-selectin and ICAM-1) may not be relevant targets in intestinal inflammation. The objective of the present study was to re-evaluate the potential role of selectins in experimental colitis in wild-type mice using the polysaccharide fucoidan, which inhibits the function of P- and L-selectin.. For this purpose, Balb/c mice were exposed to 5% dextran sodium sulfate (DSS) in the drinking water for 5 days with and without daily administration of fucoidan (25 mg/kg, i.v.). In separate experiments, the effect of fucoidan on leukocyte-endothelium interactions was examined by use of intravital microscopy.. It was found that pretreatment with fucoidan (25 mg/kg/day) reduced mucosal damage and crypt destruction in the colon of DSS-treated mice. Moreover, this fucoidan treatment markedly reduced the colonic MPO activity in mice exposed to DSS. In vivo microscopy revealed that the dose of fucoidan used in the present study abolished TNF-alpha-induced venular leukocyte rolling and extravascular recruitment.. These results suggest that selectins mediate leukocyte infiltration and tissue damage in experimental colitis. Moreover, our data support the concept that functional interference with adhesion molecules of the selectin family may have a beneficial effect in the treatment of inflammatory bowel disease. Topics: Animals; Colitis; Dextran Sulfate; Disease Models, Animal; Immunohistochemistry; Inflammation Mediators; Intestinal Mucosa; Leukocytes; Male; Mice; Mice, Inbred BALB C; Peroxidase; Polysaccharides; Reference Values; Selectins; Sensitivity and Specificity; Severity of Illness Index; Statistics, Nonparametric | 2001 |
Dual effect of chronic nicotine administration: augmentation of jejunitis and amelioration of colitis induced by iodoacetamide in rats.
Smoking has a dichotomous effect on inflammatory bowel disease, ameliorating disease activity in ulcerative colitis but having a deleterious effect on Crohn's disease. This effect is thought to be due to nicotine. We investigated the effect of chronic nicotine administration on the small and large bowel in iodoacetamide-induced jejunitis and colitis. Jejunitis was induced in Sprague-Dawley rats by intrajejunal administration of 0.1 ml 2% iodoacetamide and colitis by intrarectal administration of 0.1 ml 3% iodoacetamide. Nicotine was dissolved in drinking water (12.5 or 250 micrograms/ml), rats drinking ad libitum. Nicotine administration started 10 days prior to damage induction and throughout the experiment and had no effect on weight gain or daily food intake of rats. Rats were killed 5 days after iodoacetamide-induced colitis and 7 days after induction of jejunitis. The jejunum and colon were resected, rinsed, weighed, damage assessed macroscopically and microscopically and tissue processed for myeloperoxidase and nitric oxide synthase (NOS) activities and prostaglandin E2 (PGE2) generation. Effects of nicotine on gut microcirculation were also assessed. Nicotine by itself caused no damage to the colon. Nicotine had a dichotomous effect on jejunitis and colitis. At a dose of 12.5 micrograms/ml nicotine improved the macroscopic damage of colitis from 252 +/- 66 to 70 +/- 31 mm2, and segmental weight also declined significantly in the colon (from 1.7 +/- 0.2 to 1.2 +/- 0.1 g/10 cm). In contrast, the same dose of nicotine had a deleterious effect on iodoacetamide-induced jejunitis, increasing the macroscopic damage from 368 +/- 38 to 460 +/- 97 mm2 in rats treated with injury escalating to 970 +/- 147 in rats treated with 250 micrograms/ml nicotine. Nicotine treatment also significantly increased jejunal segmental weight. By itself nicotine did not change NOS activity or PGE2 generation compared to control rats, but it enhanced microcirculation in the colon, whereas in the jejunum nicotine decreased PGE2 generation and increased NOS activity but not jejunal microcirculation. Nicotine has opposite effects on iodoacetamide-induced colitis and jejunitis, which may be partly explained by decreased PGE2 generation and increased NOS activity in the jejunum and an increase in the colonic microcirculation. Topics: Animals; Colitis; Dinoprostone; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Enteritis; Intestinal Mucosa; Iodoacetamide; Jejunal Diseases; Male; Nicotine; Nitric Oxide Synthase; Peroxidase; Probability; Rats; Rats, Sprague-Dawley; Reference Values; Sensitivity and Specificity; Statistics, Nonparametric | 2001 |
Evidence of local eosinophil activation and altered mucosal permeability in collagenous colitis.
The local release of the inflammatory mediators eosinophil cationic protein and myeloperoxidase and the permeability marker albumin was studied in collagenous colitis using a new technique for segmental perfusion of the rectum and descending colon. Perfusion of both segments was successful in 19/25 (76%) of patients with collagenous colitis and controls with noninflammatory conditions. The concentration of myeloperoxidase was increased in the perfusion fluids from both segments in only one patient with collagenous colitis and in none of the controls. On the other hand, concentrations of eosinophil cationic protein and albumin in the perfusate from the rectum were significantly increased in collagenous colitis compared with controls, and similar trends were seen in the perfusates from the descending colon. Furthermore, there was a significant correlation between the increased concentrations of eosinophil cationic protein and albumin, indicating a possible relation between eosinophil activation and disturbed mucosal permeability in collagenous colitis. Topics: Adult; Aged; Aged, 80 and over; Albumins; Blood Proteins; Colitis; Collagen; Colonoscopy; Eosinophil Granule Proteins; Eosinophils; Female; Humans; Intestinal Mucosa; Male; Middle Aged; Perfusion; Permeability; Peroxidase; Ribonucleases | 2001 |
Effect of zinc supplementation on trace elements and intestinal metallothionein concentrations in experimental colitis in the rat.
Zinc enhances cell protection against infection and injury and the healing processes themselves. We evaluated the effect of zinc supplementation at different doses on a model of experimental colitis in the rat.. Colitis, induced by intra-rectal instillation of dinitrobenzen-sulphonic acid, was assessed at 1 week by examining: general outcome and macroscopic damage, myeloperoxidase activity, mucosal zinc, iron and metallothionein concentrations. Rats received zinc sulphate, 2 mg/kg or 30 mg/kg, twice a day by gavage for 9 days, starting 3 days before the induction of colitis, or intrarectal instillation of zinc (20 mg/kg) once daily starting 8 hours after the induction of colitis and for 6 days thereafter. Zinc-treated rats had less diarrhoea, higher body weight and lower colonic weight than untreated rats but no effect was observed on macroscopic inflammation, adhesions, colonic distension and neutrophil infiltration of the colonic mucosa. Zinc supplementation did not affect mucosal iron and zinc concentrations or plasma zinc levels in colitic rats. Metallothionein synthesis was induced in control rats and to a lesser extent in colitic rats.. Zinc administration induces metallothionein synthesis but has little effect on the short-term course of experimental colitis. Topics: Administration, Oral; Administration, Rectal; Analysis of Variance; Animals; Colitis; Dietary Supplements; Disease Models, Animal; Dose-Response Relationship, Drug; Intestinal Mucosa; Male; Metallothionein; Peroxidase; Probability; Random Allocation; Rats; Rats, Sprague-Dawley; Trace Elements; Zinc | 2001 |
Colon epithelial cell death in 2,4,6-trinitrobenzenesulfonic acid-induced colitis is associated with increased inducible nitric-oxide synthase expression and peroxynitrite production.
Peroxynitrite, derived from the reaction of nitric oxide (NO(.)) with superoxide (O(2)), is a potent nitrating and oxidizing agent that can induce apoptosis in a variety of different cell types. In the present study, we investigated the possible role of peroxynitrite as a mediator of colon epithelial cell death in rat colitis. Rat colon inflammation was induced by intracolonic administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) and rats were sacrificed 24 h after TNBS administration. Expression of inducible nitric-oxide synthase (iNOS) was detected by reverse transcription-polymerase chain reaction and immunohistochemistry. The enzymatic activities of Ca(2+)-independent iNOS and Ca(2+)-dependent constitutive nitric-oxide synthase were determined biochemically. Evidence of peroxynitrite-mediated cell injury was detected by immunostaining of nitrotyrosine. Apoptosis was examined by in situ terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay and DNA gel electrophoresis. To evaluate the specific contribution of peroxynitrite to the observed cell injury, a selective iNOS inhibitor, L-N(G)-[1-iminoethyl]lysine (L-NIL), was administered after TNBS induction. Morphological examination and analysis of TUNEL/cytokeratin double immunofluorescence revealed significant apoptosis in mucosal epithelial cells. Nitrotyrosine was colocalized with TUNEL, strongly demonstrating the association of peroxynitrite with the apoptotic death of colon epithelial cells. The administration of L-NIL reduced iNOS activity in 24-h lesions by 92% and also significantly attenuated both nitrotyrosine staining and apoptotic cell counts in the colon epithelium. These results strongly suggest that local elevated level of peroxynitrite produced from increased iNOS expression and activity is a major contributor to colon epithelial apoptosis during colon inflammation. Topics: Animals; Apoptosis; bcl-2-Associated X Protein; Cell Death; Colitis; Colon; Disease Models, Animal; Epithelial Cells; Immunohistochemistry; In Situ Nick-End Labeling; Isoenzymes; Lysine; Nitrates; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Superoxides; Trinitrobenzenesulfonic Acid; Tyrosine | 2001 |
An oral drug delivery system targeting immune-regulating cells ameliorates mucosal injury in trinitrobenzene sulfonic acid-induced colitis.
Control of immune-regulating cells in the colonic mucosa is important in the treatment of patients with inflammatory bowel disease (IBD). The aim of study was to examine the therapeutic effect of dexamethasone (DX) microspheres on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats, a model for human Crohn's disease. DX microspheres and DX alone were administered orally to rats with TNBS-induced colitis. The macroscopic score, histological score, myeloperoxidase (MPO) activity, nitric oxide (NO) production, and gene expressions of proinflammatory cytokines, cyclooxygenase (COX)-1, and COX-2 in the colonic tissue were determined. Proliferating cell nuclear antigen (PCNA) staining and expression of nuclear transcription factor (NF)-kappaB in colonic tissues were also investigated. Macroscopic score, histological score, MPO activity, and NO production in rats treated with DX microspheres were significantly lower than in those treated with DX alone. The gene expression of proinflammatory cytokines and COX-2 in rats treated with DX microspheres was down-regulated, compared with that in rats treated with DX alone. The number of PCNA-positive cells in the DX microsphere group was larger than in the group treated with DX alone. DX microspheres suppressed NF-kappaB activation in TNBS-induced colitis more strongly than DX alone. Oral administration of DX microspheres appears to ameliorate mucosal injury in TNBS-induced colitis. This drug delivery system could be an ideal therapy for human IBD. Topics: Administration, Oral; Animals; Cell Division; Colitis; Cyclooxygenase 1; Cytokines; Dexamethasone; Disease Models, Animal; Drug Delivery Systems; Immunohistochemistry; Intestinal Mucosa; Isoenzymes; Male; Membrane Proteins; Microspheres; NF-kappa B; Nitric Oxide; Peroxidase; Proliferating Cell Nuclear Antigen; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Wistar; RNA, Messenger; Signal Transduction; Treatment Outcome; Trinitrobenzenesulfonic Acid | 2001 |
Antiinflammatory effects of Cordia myxa fruit on experimentally induced colitis in rats.
Products of certain species of Cordia are reported to have antiinflammatory properties. In the present study we examined the effects of Cordia myxa fruit on experimentally induced colitis in rats. Colitis was induced by intrarectal administration of 4% acetic acid. Colitic, normal, and corresponding control animals were included. Body weight was recorded daily. All the animals were sacrificed 4 days after the fruit treatment. Colitis was monitored histologically and by activity of myeloperoxidase. Glutathione peroxidase, superoxide dismutase, as well as total antioxidant status and concentrations of zinc, copper, manganese, selenium, and iron were assayed in plasma, liver, and colon using standard methods. Histology of the colon of colitic rats showed acute colitis that was confirmed by a significant increase in the myeloperoxidase activity. Colitis was associated with significant decreases in the tissue activities of glutathione peroxidase and superoxide dismutase and lower concentrations of trace elements. Histologic examination and myeloperoxidase activity showed that the fruit treatment reversed the above findings in the inflamed colon, and in liver and plasma of colitic rats. The present results suggest that the observed antiinflammatory effect of the Cordia myxa may be attributed partly to its antioxidant property and to restoration of the levels of trace elements in the inflamed colon, liver, and plasma. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Antioxidants; Boraginaceae; Colitis; Colon; Fruit; Glutathione Peroxidase; Liver; Male; Peroxidase; Phytotherapy; Plant Extracts; Rats; Rats, Wistar; Superoxide Dismutase; Trace Elements | 2001 |
Tapeworm infection reduces epithelial ion transport abnormalities in murine dextran sulfate sodium-induced colitis.
The rat tapeworm Hymenolepis diminuta was used to test the hypothesis that helminth infection could modulate murine colitis. Mice were infected with five H. diminuta cysticercoids, and colitis was evoked via free access to 4% (wt/vol) dextran sulfate sodium (DSS)-containing drinking water for 5 days. BALB/c mice were either infected with H. diminuta and 7 days later exposed to DSS (prophylactic strategy) or started on DSS and infected with H. diminuta 48 h later (treatment strategy). Naive and H. diminuta-only-infected mice served as controls. On autopsy, colonic segments were processed for histological examination and myeloperoxidase (MPO) measurement or mounted in Ussing chambers for assessment of epithelial ion transport. Cytokines (gamma interferon [IFN-gamma], interleukin 12 [IL-12], and IL-10) were measured in serum and colonic tissue homogenates. DSS treatment resulted in reduced ion responses (indicated by short-circuit current [Isc]) to electrical nerve stimulation, the cholinergic agonist carbachol, and the adenylate cyclase activator forskolin compared to controls. H. diminuta infection, either prophylactic or therapeutic, caused a significant (P < 0.05) amelioration of these DSS-induced irregularities in stimulated ion transport. In contrast, the histopathology (i.e., mixed immune cell infiltrate, edema, and ulcerative damage) and elevated MPO levels that accompany DSS colitis were unaffected by concomitant H. diminuta infection. Similarly, there were no significant differences in levels of IFN-gamma, IL-12, or IL-10 in serum or tissue from any of the treatment groups at the time of autopsy. We suggest that abolishment of colitis-induced epithelial ion transport abnormalities by H. diminuta infection provides proof-of-principle data and speculate that helminth therapy may provide relief of disease symptoms in colitis. Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Hymenolepiasis; Hymenolepis; Interferon-gamma; Interleukin-10; Interleukin-12; Intestinal Mucosa; Ion Transport; Male; Mice; Mice, Inbred BALB C; Peroxidase; Rats | 2001 |
N-(3-(aminomethyl)benzyl)acetamidine, an inducible nitric oxide synthase inhibitor, decreases colonic inflammation induced by trinitrobenzene sulphonic acid in rats.
Gastrointestinal inflammation has been associated with an increased generation of nitric oxide (NO) and the expression of the inducible NO synthase (iNOS). Using an experimental model of colitis induced by trinitrobenzene sulphonic acid (TNBS), we sought to determine whether the administration of N-(3-(Aminomethyl)benzyl)acetamidine (1400W), a specific inhibitor of iNOS, has a beneficial action on the colonic injury. 1400W (0.4 and 2 mg/kg/day) was administered intraperitoneally from day 5 to 10 after intrarectal instillation of TNBS. TNBS led to colonic ulceration and inflammation, an increase of colonic myeloperoxidase activity and the expression of the calcium-independent NOS from days 1 to 15. 1400W reduced the macroscopic damage and the histological changes induced by TNBS as well as the calcium-independent NOS activity and myeloperoxidase activity determined over 30 min after sacrifice. These findings indicate that the expression of iNOS accounts for most of the damage caused by TNBS and that the administration of 1400W after the onset of colitis has a beneficial action on the colonic injury. Topics: Amidines; Animals; Benzylamines; Blotting, Western; Colitis; Colon; Disease Models, Animal; Drug Administration Schedule; Enzyme Activation; Enzyme Inhibitors; Female; Injections, Intraperitoneal; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2001 |
Suppression of acute experimental colitis by a highly selective inducible nitric-oxide synthase inhibitor, N-[3-(aminomethyl)benzyl]acetamidine.
High concentrations of nitric oxide (NO) produced by the inducible nitric-oxide synthase (iNOS) are associated with ulcerative inflammation and disease activity in colitis. Therefore, inhibition of iNOS serves as a novel experimental approach to treat gut inflammation. The aim of the present study was to investigate the effects of a novel highly selective iNOS inhibitor, N-[3-(aminomethyl)benzyl]acetamidine (1400W), as compared with a nonselective NOS inhibitor, N(G)-nitro-L-arginine-methyl-ester (L-NAME), in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced acute colitis in the rat. Increased expression of iNOS protein and mRNA was found in acute TNBS-induced colitis along with neutrophil infiltration, inflammatory edema, and tissue damage. In a 24-h model of acute colitis, subcutaneous injections of 1400W (5 or 10 mg/kg t.i.d.) produced a 56 and 95% reduction in inflammatory edema formation, a 68 and 63% reduction in neutrophil infiltration (measured as myeloperoxidase activity), and a 19 and 26% decrease in the size of mucosal lesions as compared with vehicle treatment. Administration of L-NAME (35 mg/kg) failed to produce any significant beneficial effects as compared with vehicle treatment in this experimental model of acute colitis. Treatment with 1400W, a highly selective inhibitor of iNOS, reduced formation of edema, neutrophil infiltration, and macroscopic inflammatory damage in experimentally induced acute colitis in the rat. In contrast, nonselective nitric-oxide synthase inhibition with L-NAME provided no benefit. These results support the idea that selective iNOS inhibitors have a promise in the treatment of colitis. Topics: Amidines; Animals; Anti-Inflammatory Agents; Benzylamines; Blotting, Western; Colitis; Colon; Enzyme Inhibitors; Male; Neutrophil Infiltration; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Organ Size; Peroxidase; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Trinitrobenzenesulfonic Acid | 2001 |
Mice with combined disruption of Gpx1 and Gpx2 genes have colitis.
Glutathione peroxidase (GPX)-1 and gastrointestinal (GI) epithelium-specific GPX (GPX-GI), encoded by Gpx1 and Gpx2, provide most GPX activity in GI epithelium. Although homozygous mice deficient in either the Gpx1 or Gpx2 gene appeared to be normal under standard housing conditions, homozygous mice deficient in both genes, double-knockout (KO) mice, had symptoms and pathology consistent with inflammatory bowel disease. These symptoms included a high incidence of perianal ulceration, growth retardation that started around weaning, and hypothermia that resembled that observed in calorie-restricted mice, even though the double-KO mice in our study were allowed to eat ad libitum. The growth retardation and hypothermia were components of cachexia, which is fatal in a high percentage of mice. Histological examination revealed that the double-KO mice had a high incidence of mucosal inflammation in the ileum and colon but not in the jejunum. Elevated levels of myeloperoxidase activity and lipid hydroperoxides were also detected in colon mucosa of these homozygous double-KO mice. These results suggest that GPX is essential for the prevention of the inflammatory response in intestinal mucosa. Topics: Animals; Colitis; Colon; Disease Models, Animal; Disease Progression; Glutathione Peroxidase; Glutathione Peroxidase GPX1; Growth Disorders; Homozygote; Hypothermia; Ileum; Lipid Peroxides; Mice; Mice, Knockout; Peroxidase; Phenotype; Rectum | 2001 |
Combinations of neurokinin receptor antagonists reduce visceral hyperalgesia.
The effect of selective neurokinin receptor (NKR) antagonists for the NK1R (SR140,333), NK2R (SR48,968), and NK3R (SR142,801) on the visceromotor response to noxious colorectal distension (CRD) was examined. NKR antagonists or vehicle were given intrathecally (i.th.) to rats made hyperalgesic by intracolonic instillation of zymosan or after intracolonic instillation of saline (control). Given alone, the NK1R (up to 3 microg of SR140,333) and NK2R (up to 60 microg of SR48,968) antagonists tested failed to significantly affect responses to the noxious visceral stimulus. However, coadministration of 3 microg of SR140,333 and 60 microg of SR48,968 (both i.th.) significantly reduced responses to noxious CRD (p < 0.05 versus vehicle). The NK3R antagonist (60 microg of SR142,801) significantly reduced responses to noxious CRD when given alone to either hyperalgesic (zymosan-treated) or normal (saline-treated) rats (p < 0.05 versus vehicle for both groups). Responses of rats receiving the NK3R antagonist in combination with either the NK1R or the NK2R antagonist were not different from rats receiving the NK3R antagonist alone. These results suggest that activation of spinal NK1R and NK2R, presumably by their endogenous ligands (substance P and neurokinin A), maintain visceral hyperalgesia and support the notion that activation of NK3R (presumably by neurokinin B) is pronociceptive. Topics: Animals; Benzamides; Biomarkers; Colitis; Drug Interactions; Hyperalgesia; Injections, Spinal; Male; Motor Activity; Neurokinin-1 Receptor Antagonists; Pain Measurement; Peroxidase; Piperidines; Quinuclidines; Rats; Rats, Sprague-Dawley; Receptors, Neurokinin-2; Receptors, Neurokinin-3; Zymosan | 2001 |
Heparin and low-molecular-weight heparin (enoxaparin) significantly ameliorate experimental colitis in rats.
The anticoagulants, unfractionated heparin and low-molecular-weight heparin, demonstrated anti-inflammatory effects in animal models and in humans. Because of its dual effects, high-dose heparin was proposed as a therapeutic modality for ulcerative colitis. We investigated whether a low dose of low-molecular-weight heparin-enoxaparin (Clexane, Rhône-Poulenc Rorer, France)-ameliorates the inflammatory response in two models of experimental colitis.. Colitis was induced in rats by intrarectal administration of dinitrobenzene sulphonic acid. Enoxaparin (40, 80 and 200 microg/kg) or unfractionated heparin (100, 200 and 400 U/kg) were administered subcutaneously immediately after the induction of damage. Enoxaparin, 80 microg/kg, was also administered after induction of colitis by intrarectal administration of iodoacetamide. Rats were sacrificed 1, 3 or 7 days after induction of injury. Colonic damage was assessed macroscopically and histologically. Mucosal prostaglandin E2 generation, myeloperoxidase and nitric oxide synthase activities and tumour necrosis factor-alpha levels in blood were determined.. Enoxaparin and heparin significantly ameliorated the severity of dinitrobenzene sulphonic acid- and iodoacetamide-induced colitis as demonstrated by a decrease in mucosal lesion area, colonic weight and mucosal myeloperoxidase and nitric oxide synthase activities. The dose-response curve had a bell-shaped configuration: enoxaparin, 80 microg/kg, and unfractionated heparin, 200 U/kg, were the optimal doses.. Low-dose enoxaparin and unfractionated heparin ameliorate the severity of experimental colitis. This effect is related to their anti-inflammatory rather than anticoagulant properties. Topics: Animals; Anti-Inflammatory Agents; Anticoagulants; Benzenesulfonates; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Enoxaparin; Heparin; Iodoacetamide; Male; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha | 2001 |
In vivo inhibition of cyclooxygenase-2 by a selective phosphorothioated oligonucleotide.
Inhibition of cyclooxygenase-2 (cox-2) is considered to be anti-inflammatory, whereas inhibition of the constitutive isozyme cox-1 causes renal and gastrointestinal toxicity. Therefore, to achieve an optimal anti-inflammatory effect, an inhibitor should be cox-2 selective without inhibiting cox-1. For this purpose, 10 different cox-2-selective phosphorothioated oligonucleotides (S-oligos) were tested to inhibit the cox-2 enzyme selectively in vivo. An aqueous solution of these S-oligos (3 mg/kg body weight) was injected intraperitoneally (i.p.) into male Sprague-Dawley rats with colitis induced by trinitrobenzene sulfonic acid (TNBS). The colonic levels of cox-2 protein, mRNA, myeloperoxidase (MPO), and prostaglandin E2 (PGE2) were increased significantly on day 1 and remained significantly elevated until day 7 post-TNBS administration, whereas cox-1 remained unaltered. Two S-oligos were found to be effective in reducing the level of cox-2 protein selectively without any effect on the cox-1. The effective S-oligo, but not the mismatched control oligo, reduced the tissue levels of PGE2 and MPO activity significantly. The effective S-oligo reduced the level of cox-2 but not the cox-1 mRNA significantly, whereas a mismatched or a sense control oligo did not affect the levels of these isoforms. M-fold analysis demonstrated extensive secondary structure formation in the cox-2 mRNA. These findings demonstrate that only a few selected sites in the cox-2 target mRNA are accessible in vivo, probably because of the presence of secondary structures. Suppression of cox-2 protein, PGE2, and MPO activity by the S-oligo might prove to be an anti-inflammatory property. Topics: Animals; Biomarkers; Colitis; Colon; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Dinoprostone; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Enzyme Induction; Isoenzymes; Male; Membrane Proteins; Nucleic Acid Conformation; Oligodeoxyribonucleotides, Antisense; Peroxidase; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Sprague-Dawley; RNA, Messenger; Substrate Specificity; Thionucleotides | 2001 |
Colon epithelial cellular protein induces oral tolerance in the experimental model of colitis by trinitrobenzene sulfonic acid.
Rectal administration of trinitrobenzene sulfonic acid (TNBS) produces chronic colitis in experimental animals. However, the role of epithelial cellular protein(s) in this model is unknown. We examined whether oral tolerance can be induced in this model with colon epithelial cell proteins and whether it is organ specific. Rats were fed five times with extracts of LS-180 human colon cancer cells or HT 1080 human fibroblast cells. Syngeneic normal rat colon or small intestinal extracts were fed to separate groups of rats. After oral feedings, each rat received TNBS by enema. Rats were killed 15 days later, and the following were measured: gross and histologic disease score, weight, thickness, and myeloperoxidase values of colon and serum interferon-gamma (IFN-gamma) and transforming growth factor-beta (TGF-beta) levels. Rectal TNBS alone produced severe colitis with a 26% mortality rate. Rats fed LS-180 or rat colon extract before TNBS enema were protected, as evidenced by reductions in mortality rate, disease scores, and myeloperoxidase values. However, rats fed HT 1080 or small intestine extract lacked such protection. To examine the possible mechanism of the oral tolerance, T lymphocytes from mesenteric lymph nodes and spleen of LS-180 extract-fed rats were passively transferred to naive rats, and this was followed by TNBS enema. These rats showed clear protection. Protected animals had low IFN-gamma and high TGF-beta levels. This study demonstrates that cellular protein(s) from human colon epithelial cells, but not from human fibroblasts, can induce oral tolerance in experimental colitis. This oral tolerance is mediated by primed mesenteric and splenic T lymphocytes. Topics: Administration, Oral; Animals; Cell Extracts; Colitis; Colon; Colonic Neoplasms; Epithelium; Female; Fibroblasts; Humans; Immune Tolerance; Immunization, Passive; Interferon-gamma; Intestine, Small; Lymph Nodes; Peroxidase; Proteins; Rats; Rats, Sprague-Dawley; Rectum; Spleen; Tissue Extracts; Transforming Growth Factor beta; Trinitrobenzenesulfonic Acid; Tumor Cells, Cultured | 2001 |
Dietary vitamin E supplementation protects the rat large intestine from experimental inflammation.
Vitamin E, the most potent antioxidant in the lipid phase, was tested for antiinflammatory activity in trinitrobenzenesulfonic acid-induced rat colitis. Rats were fed a nonpurified diet (saline and control groups) or a vitamin E supplemented diet (treated group, 300 mg/kg nonpurified diet). Vitamin E supplementation, which resulted in increased colonic vitamin E levels, reduced colonic weight and damage score, prevented lipid peroxidation and diarrhea, reduced interleukin-1 beta levels and preserved glutathione reductase activity and total glutathione levels. However, it did not modify myeloperoxidase levels, which are indicative of neutrophil infiltration in the inflamed colon. Vitamin E protects the rat colon from oxidative stress associated with inflammation. Topics: Animals; Colitis; Dietary Supplements; Female; Glutathione; Glutathione Reductase; Interleukin-1; Intestine, Large; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Wistar; Vitamin E | 2001 |
Quantification of mucosal leucocyte endothelial cell interaction by in vivo fluorescence microscopy in experimental colitis in mice.
Leucocyte recruitment to sites of intestinal inflammation is a crucial, multi-step process that leads ultimately to the accumulation of cells in the inflamed tissue. We established a new in vivo model system of experimental colitis to quantify leucocyte-endothelial cell interaction and leucocyte extravasation in the inflamed mucosa of the colon. Furthermore, we investigated the pathophysiological role of ICAM-1 in the intestinal microcirculation in vivo. Using the model of dextran sodium sulphate (DSS)-induced acute and chronic colitis in mice, in vivo microscopy was performed in the colonic submucosal postcapillary venules and the submucosal collecting venules in normal or inflamed murine colonic segments. ICAM-1 expression was blocked by an anti-ICAM-1 monoclonal antibody or by suppressing NF-kappaB activation by gliotoxin. Significant increases in leucocyte adhesiveness (51-fold in postcapillary venules, 30-fold in collecting venules, P < 0.01) and extravasation (6.5-fold) could be demonstrated as early as day 2 of DSS-application in acute colitis (P < 0.01). This was paralleled by increases in both the histological damage scores and myeloperoxidase activities. In chronic dextran sodium sulphate-induced colitis significant increases in leucocyte-endothelium interactions and leucocyte extravasation were observed. Blocking ICAM-1 expression with a monoclonal antibody or gliotoxin, leucocyte sticking and extravasation were significantly down-regulated in vivo compared to controls (> 70%; P < 0.01). This new model system offers the possibility to specifically assess the role of adhesion molecules in the colonic mucosa in vivo as well as to investigate and quantify the effectiveness of experimental therapeutic approaches in acute or chronic intestinal inflammation. Topics: Acute Disease; Animals; Cell Adhesion; Cell Communication; Cell Movement; Chronic Disease; Colitis; Dextran Sulfate; Endothelium, Vascular; Female; Immunohistochemistry; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Leukocytes; Mice; Mice, Inbred BALB C; Microscopy, Electron; Microscopy, Fluorescence; Peroxidase | 2001 |
Ozone enema: a model of microscopic colitis in rats.
Ozone is one of the most powerful oxidants available, with many applications in industry and medicine. Medically relevant features of ozone include bacterial and virucidal properties, disinfection, sterilization, circulatory stimulation, and disruption of malignant cells. Ozone therapy is administered in various ways, including intravenously, intramuscularly, and intrarectally. The latter modality is used for the treatment of colitis and hepatitis. Our aim was to examine the effect of ozone water enema on normal and inflamed rat colonic mucosa. Ozone water (20 microg/ml) was prepared via ozone generator and administered intrarectally (0.5 ml) daily. Rats were killed one, three, and seven days after rectal ozone water administration, and their colons resected, rinsed, and weighed (grams per 10 cm). Damage was assessed macro- and microscopically and tissue processed for myeloperoxidase and nitric oxide synthase activity. Rats receiving saline served as controls. In an additional experiment colitis was induced by intrarectal iodoacetamide. Ozone therapy caused no macroscopic damage. Ozone therapy induced microscopic colitis, which lasted for at least a week and was accompanied by increase in segmental weight, myeloperoxidase and nitric oxide activity, and prostaglandin E2 generation. Ozone therapy had no protective effect on inflamed mucosa. In conclusion, ozone water therapy had a deleterious effect on normal colonic mucosa, suggesting intrarectal administration be reevaluated. Ozone water enema may serve as a model of microscopic colitis. Topics: Administration, Rectal; Animals; Colitis; Colon; Dinoprostone; Enema; Iodoacetamide; Male; Nitric Oxide Synthase; Ozone; Peroxidase; Rats; Rats, Sprague-Dawley | 2001 |
Celecoxib, a selective cyclo-oxygenase-2 inhibitor reduces the severity of experimental colitis induced by dinitrobenzene sulfonic acid in rats.
Inflammatory bowel disease is characterised by oxidative and nitrosative stress, leukocyte infiltration, upregulation of the expression of intercellular adhesion molecule 1 (ICAM-1) and upregulation of P-selectin in the colon. Here, we investigate the effects of the selective cyclo-oxygenase-2 inhibitor, celecoxib, in rats subjected to experimental colitis. Colitis was induced in rats by intracolonic instillation of dinitrobenzene sulfonic acid (DNBS). Rats experienced hemorrhagic diarrhoea and weight loss. At 4 days after administration of DNBS, the mucosa of the colon exhibited large areas of necrosis. Neutrophil infiltration (determined by histology, as well as an increase in myeloperoxidase activity in the mucosa) was associated with upregulation of ICAM-1 and P-selectin, as well as high tissue levels of malondialdehyde. Immunohistochemistry for nitrotyrosine and poly(ADP-ribose) polymerase showed intense staining in the inflamed colon. Celecoxib (5 mg/kg twice a day orally) significantly reduced the degree of hemorrhagic diarrhoea and the weight loss caused by administration of DNBS. Celecoxib also caused a substantial reduction of (i) the degree of colonic injury, (ii) the rise in myeloperoxidase activity (mucosa), (iii) the increase in the tissue levels of malondialdehyde, (iv) the increase in staining (immunohistochemistry) for nitrotyrosine, as well as (v) the upregulation of ICAM-1 and P-selectin caused by DNBS in the colon. Thus, we provide the first evidence that a selective cyclo-oxygenase-2 inhibitor celecoxib reduces the degree of colitis caused by DNBS. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzenesulfonates; Body Weight; Celecoxib; Colitis; Colon; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Cytokines; Immunohistochemistry; Intercellular Adhesion Molecule-1; Isoenzymes; Lipid Peroxidation; Male; Neutrophils; P-Selectin; Peroxidase; Peroxynitrous Acid; Poly(ADP-ribose) Polymerases; Prostaglandin-Endoperoxide Synthases; Pyrazoles; Rats; Rats, Sprague-Dawley; Sulfonamides | 2001 |
Effects of tumour necrosis factor-alpha synthesis inhibitors on rat trinitrobenzene sulphonic acid-induced chronic colitis.
The fact that tumour necrosis factor-alpha (TNF-alpha) is clearly involved in the pathogenesis of intestinal bowel disease, especially Crohn's disease, suggests that TNF-alpha synthesis inhibitors could be beneficial for treatment. The present study assessed the effect of chronic oral gavage of two in vitro TNF-alpha synthesis inhibitors, JM 34 maleate or [N-(4,6-dimethylpyridin-2-yl)-furane-2-carboxamide)] maleate and XC 21 or (N-betapicolyl-tetrafluorophtalimide), on colonic inflammation in trinitrobenzene sulphonic acid-induced colitis in rats. Rats received JM 34 maleate (100 mg/kg) and XC 21 (50 mg/kg) 1 h before colitis induction and then daily for 8 days by oral gavage. The colon was removed on day 8 and processed for clinical score, myeloperoxidase activity, and soluble TNF-alpha release. Treatment with XC 21, as well as dexamethasone and sulphasalazine, reduced colonic damage and decreased (except with dexamethasone) the incidence of diarrhoea. JM 34 maleate failed to improve the clinical signs of chronic colitis. After trinitrobenzene sulphonic acid-induced colitis, myeloperoxidase activity and TNF-alpha colonic mucosal production were substantially increased compared to the control (saline instillation). Both of these inflammatory indicators were then significantly decreased (P< or =0.05) after the four chronic treatments (JM 34 maleate, XC 21, sulphasalazine, and dexamethasone). XC 21 appeared to be as efficient as sulphasalazine in improving colonic inflammation. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzamides; Chronic Disease; Colitis; Colon; Disease Models, Animal; Enzyme Inhibitors; Peroxidase; Rats; Rats, Wistar; Sulfasalazine; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 2001 |
Protective effects of M40403, a superoxide dismutase mimetic, in a rodent model of colitis.
Inflammatory bowel disease is characterised by oxidative and nitrosative stress, leukocyte infiltration, and up-regulation of intercellular adhesion molecule 1 (ICAM-1) expression in the colon. The aim of the present study was to examine the effects of M40403, a superoxide dismutase mimetic, in rats subjected to experimental colitis. Colitis was induced in rats by intracolonic instillation of trinitrobenzene sulfonic acid (TNBS). Rats experienced bloody diarrhoea and significant loss of body weight. At 4 days after TNBS administration, the colon damage was characterised by areas of mucosal necrosis. Neutrophil infiltration (indicated by myeloperoxidase activity in the mucosa) was associated with up-regulation of ICAM-1 and expression of P-selectin and high levels of malondialdehyde. Immunohistochemistry for nitrotyrosine and poly (ADP-ribose) synthetase showed an intense staining in the inflamed colon. Treatment with M40403 (5 mg/kg daily i.p.) significantly reduced the appearance of diarrhoea and the loss of body weight. This was associated with a remarkable amelioration of the disruption of the colonic architecture as well as a significant reduction of colonic myeloperoxidase activity and malondialdehyde levels. M40403 also reduced the appearance of nitrotyrosine and poly (ADP-ribose) synthetase immunoreactivity in the colon as well as reduced the up-regulation of ICAM-1 and the expression of P-selectin. The results of this study suggested that administration of a superoxide dismutase mimetic may be beneficial for treatment of inflammatory bowel disease. Topics: Animals; Body Weight; Colitis; Colon; Cytokines; Enzyme Activation; Free Radical Scavengers; Immunohistochemistry; Intercellular Adhesion Molecule-1; Lipid Peroxidation; Male; Manganese; Organometallic Compounds; P-Selectin; Peroxidase; Poly(ADP-ribose) Polymerases; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; Survival Analysis; Time Factors; Tyrosine | 2001 |
Role of appendix and spleen in experimental colitis.
There is growing clinical evidence suggesting that certain secondary lymphoid tissues (e.g., appendix and spleen) contribute to the initiation and/or perpetuation of ulcerative colitis. In this study, the importance of secondary lymphoid tissues in inducing colitis was assessed experimentally by removing the spleen and/or appendix (or sham operation) prior to inducing colitis in mice. Feeding 2.5% dextran sulphate sodium (DSS) in drinking water over 7 days induced colitis. Clinical disease activity was assessed based on weight loss, stool consistency, and presence of blood in stools. Additional measurements included white blood cell count and hematocrit, and myeloperoxidase activity (MPO) in colon samples. Colonic injury was assessed by histology and computerized image analysis. DSS treatment in sham-operated mice produced colitis associated with weight loss, bloody diarrhea, and mucosal ulceration. Clinical assessment of DSS-treated mice subjected to appendectomy or combined appendectomy/splenectomy exhibited a delayed onset and course of disease activity. Histomorphologic examination revealed significantly lower damage scores and a reduction in ulcerated mucosal surface area. Colonic MPO activity, which correlated with tissue injury and disease activity, was lowest in appendectomized mice. No beneficial effects of splenectomy were observed after 7 days of colitis. These findings support the hypothesis that appendicular lymphoid tissue, but not the spleen, contributes to the development of colitis. Topics: Animals; Appendectomy; Appendix; Colitis; Colon; Dextran Sulfate; Inflammatory Bowel Diseases; Male; Mice; Mice, Inbred C57BL; Peroxidase; Spleen; Splenectomy | 2001 |
Intestinal anti-inflammatory activity of morin on chronic experimental colitis in the rat.
Morin, a bioflavonoid with antioxidant properties, shows intestinal anti-inflammatory activity in the acute phase of the trinitrobenzenesulphonic acid model of rat colitis.. To assess the anti-inflammatory activity of morin in the chronic stages of trinitrobenzenesulphonic acid-induced rat colitis.. Rats were rendered colitic by a single colonic instillation of 30 mg of the hapten trinitrobenzenesulphonic acid dissolved in 0.25 mL of 50% ethanol. A group of colitic animals was given morin orally at doses of 25 mg/kg daily. Animals were sacrificed every week for 4 weeks. Colonic damage was evaluated macroscopically and microscopically. Different biochemical markers of colonic inflammation were also assayed, including myeloperoxidase activity, leukotriene B4 and interleukin-1beta synthesis, glutathione and malonyldialdehyde levels and nitric oxide synthase activity.. The administration of morin facilitated tissue recovery during the 4 weeks following colonic insult with trinitrobenzenesulphonic acid, as demonstrated macroscopically and microscopically, as well as biochemically by a reduction in myeloperoxidase activity. The intestinal anti-inflammatory effect of morin was accompanied by a significant reduction in colonic leukotriene B4 and interleukin-1beta levels, improvement in colonic oxidative stress and inhibition of colonic nitric oxide synthase activity.. Morin exerts a beneficial anti-inflammatory effect in the chronic phase of trinitrobenzenesulphonic acid-induced rat colitis through the down-regulation of some of the mediators involved in the intestinal inflammatory response, including free radicals, cytokines, leukotriene B4 and nitric oxide. Topics: Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Chronic Disease; Colitis; Disease Models, Animal; Female; Flavonoids; Interleukin-1; Intestinal Mucosa; Leukotriene B4; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2001 |
Beneficial effects of glycocholic acid (GCA) on gut mucosal damage in bile duct ligated rats.
In order to investigate the effect of bile acids on gastrointestinal inflammations, bile duct ligated rats (BDL) were treated with GCA (25 mM/ml, oral or colonic) or saline I h before ethanol challenge and twice daily for 3 days in the ileitis group, while GCA was given twice daily for 3 days in the colitis group. BDL reduced the macroscopic and microscopic damage scores in the ileitis group compared to sham operated group, while it had no significant effect on ulcer or colitis groups. However, GCA given in BDL group reduced the ulcer index and microscopic damage in colitis group compared to saline-treated groups, but had no effect in ileitis group. Both BDL and GCA administration in BDL group reduced ileitis- or colitis-induced elevations in MPO levels. GCA administration in BDL group inhibited gastric acid output and volume. Our results suggest that oral or colonic administration of primary bile acids may be useful for the treatment of gastrointestinal inflammations. Topics: Animals; Bile Acids and Salts; Bile Ducts; Colitis; Disease Models, Animal; Ethanol; Gastric Acid; Glycocholic Acid; Ileitis; Inflammatory Bowel Diseases; Intestinal Mucosa; Ligation; Peptic Ulcer; Peroxidase; Rats | 2001 |
Lycopene supplementation attenuates the inflammatory status of colitis in a rat model.
The aim of this study was to examine the influence of lycopene and beta-carotene on the inflammatory status in a rat model of induced-colitis. Using the 2,4,6-trinitrobenzenesulfonic acid (TNBS) model, colitis was induced in thirty-two male Wistar rats divided into four groups. Each group received a different diet regime in parallel with the induction of colitis and was sacrificed after seven days. The groups were divided as follows: Group A: without colitis and fed a normal chow diet; Group B: induced with colitis and fed a diet supplemented with lycopene (300 micrograms/rat/day); Group C: induced with colitis and fed a diet supplemented with beta-carotene (300 micrograms/rat/day); Group D: induced with colitis and fed a normal chow diet. Colonic inflammation following TNBS induction was characterized by hemorrhagic necrosis and fibrosis of the mucosa, increased colonic wall thickness, infiltration of inflammatory cells, and increased myeloperoxidase (MPO) activity. Supplementation of lycopene in the diet had a beneficial effect on the various macroscopic parameters examined including: colonic thickness, colon weight, and total area of inflammation. Furthermore, the level of myeloperoxidase (MPO) was significantly lower in the lycopene-treated group compared to the control group. In terms of microscopic changes, a more attenuated inflammatory reaction was observed in the group fed a diet supplemented with lycopene. No significant effect was noted in the beta-carotene-supplemented group. Therefore, we propose that the dietary supplementation of lycopene may be an effective approach for reducing the level of oxidative stress and improving the inflammatory status of colitis. Topics: Analysis of Variance; Animals; Antioxidants; beta Carotene; Carotenoids; Colitis; Colon; Inflammation; Lycopene; Male; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 2001 |
Implication of TNF-alpha convertase (TACE/ADAM17) in inducible nitric oxide synthase expression and inflammation in an experimental model of colitis.
Tumour necrosis factor-alpha (TNF-alpha) is a pro-inflammatory cytokine which is shed in its soluble form by a disintegrin and metalloproteinase (ADAM) called TNF-alpha convertase (TACE; ADAM17). TNF-alpha plays a role in inflammatory bowel disease (IBD) and is involved in the expression of inducible nitric oxide synthase (iNOS) which has also been implicated in IBD. The study was designed to investigate whether colitis induced by trinitrobenzene sulphonic acid (TNBS) in rats produces an increase in TACE activity and/or expression and whether its pharmacological inhibition reduces TNF-alpha levels, iNOS expression and colonic damage in this model. TNBS (30 mg in 0.4 ml of 50% ethanol) was instilled into the colon of female Wistar rats. Saline or TACE inhibitor BB1101 (10 mg/kg/day) was administered intraperitoneally 5 days after TNBS instillation. On day 10, colons were removed and assessed for pathological score, myeloperoxidase (MPO), NO synthase (NOS), TACE enzymatic activity and protein levels, colonic TNF-alpha and NOx- levels. Instillation of TNBS caused an increase in TACE activity and expression and the release of TNF-alpha. TNBS also resulted in iNOS expression and colonic damage. BB1101 blocked TNBS-induced increase in TACE activity, TNF-alpha release and iNOS expression. Concomitantly, BB1101 ameliorated TNBS-induced colonic damage and inflammation. TNBS causes TNF-alpha release by an increase in TACE activity and expression and this results in the expression of iNOS and subsequent inflammation, suggesting that TACE inhibition may prove useful as a therapeutic means in IBD. Topics: ADAM Proteins; ADAM17 Protein; Animals; Blotting, Western; Body Weight; Colitis; Enzyme-Linked Immunosorbent Assay; Female; Inflammation; Metalloendopeptidases; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar | 2001 |
Development of an oral drug delivery system targeting immune-regulating cells in experimental inflammatory bowel disease: a new therapeutic strategy.
Several studies have indicated the involvement of macrophages and dendritic cells in active inflammatory bowel disease (IBD). Manipulation of these cells is considered a very important therapeutic strategy for patients with IBD. We evaluated the effect of a new drug delivery system targeting microfold cells and macrophages with poly(DL-lactic acid) microspheres containing dexamethasone (Dx). Colitis was induced in BALB/c mice by 5% dextran sodium sulfate. Dx microspheres (n = 10) and only Dx (n = 10) were orally administered to dextran sodium sulfate-treated mice. Thereafter, serum levels and tissue distributions of Dx were investigated. To estimate the efficacy of this drug delivery system, we measured the histological score, myeloperoxidase activity and nitric oxide production, and gene expressions of tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma in the colonic tissue. Serum Dx levels were not increased after oral administration of Dx microspheres. The tissue distribution of microspheres containing (125)I-labeled Dx in inflamed colon was significantly higher than in other organs. The histological score, myeloperoxidase activity, and nitric oxide production of the group treated with Dx microspheres were significantly lower than of those treated with Dx alone. Gene expressions of tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma were down-regulated in mice treated with Dx microspheres. Microspheres containing glucocorticoids such as Dx, which target microfold cells and macrophages, can facilitate mucosal repair in experimental colitis and could be an ideal agent for treatment of human IBD. Topics: Administration, Oral; Animals; Body Weight; Colitis; Colon; Dexamethasone; Dextrans; Drug Delivery Systems; Female; Gene Expression; Interferon-gamma; Interleukin-1; Lactic Acid; Macrophages; Mice; Mice, Inbred BALB C; Microspheres; Nitric Oxide; Peroxidase; Polyesters; Polymers; RNA, Messenger; Time Factors; Tumor Necrosis Factor-alpha | 2000 |
Site-specific lesion formation, inflammation and inducible nitric oxide synthase expression by indomethacin in the rat intestine.
The involvement of nitric oxide (NO) formed by the inducible isoform of NO synthase (iNOS) has been investigated in the development of rat intestinal lesions following indomethacin administration. Over a 72-h period, indomethacin (10 mg kg(-1), s.c.) provoked a time-dependent increase in expression of iNOS (assessed by the conversion of radiolabelled L-arginine to citrulline) and enhancement of vascular leakage of radiolabelled human serum albumin in the jejunum which commenced 18 h after indomethacin. Similar effects were not observed in the ileum, colon or caecum. In addition, macroscopic lesions were detectable and myeloperoxidase activity (an index of neutrophil recruitment) were increased in the rat jejunum 18-24 h after indomethacin, but remained at basal levels in the ileum and colon. These findings suggest that indomethacin provokes a site-selective expression of iNOS in the rat jejunum which correlates with lesion formation and vascular leakage, whereas both the ileum and colon are spared. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Capillary Permeability; Colitis; Enteritis; Enzyme Induction; Indomethacin; Intestinal Mucosa; Intestine, Large; Intestine, Small; Male; Neutrophils; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Organ Specificity; Peroxidase; Rats; Rats, Wistar | 2000 |
Interleukin-12 induced interferon-gamma increases inflammation in acute dextran sulfate sodium induced colitis in mice.
There is increasing evidence that IL-12 and Th1-cytokines play an important role in intestinal inflammation. We therefore examined the role of IL-12 and interferon-gamma (IFN-gamma) in our model of dextran sulfate-induced acute colitis in mice. Treatment of mice with rmIL-12 during colitis induction resulted in severe aggravation as demonstrated by a greater loss of body weight, an increase of the histological parameters, and reduction of myeloperoxidase activity in colonic biopsies. Depletion of neutrophils in mice also led to aggravation of colitis. Neutralization of IFN-gamma in IL-12-treated mice with colitis inhibited these effects of IL-12. Neutralization of endogenous IFN-gamma or IL-12 with specific antibodies in DSS-treated mice, however, had only weak ameliorating effects. Since IL-12 and IFN-gamma have been shown to mediate experimental chronic colitis we conclude that the transition from a macrophage/neutrophil determined response to a Th-cell response promotes chronic intestinal inflammation. Topics: Animals; Antibodies, Monoclonal; Colitis; Dextran Sulfate; Female; Gene Expression Regulation; Inflammation; Interferon-gamma; Interleukin-12; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Peroxidase; Recombinant Proteins; RNA, Messenger; Transcription, Genetic; Weight Loss | 2000 |
Iron supplementation may aggravate inflammatory status of colitis in a rat model.
Iron supplementation is one of the principal therapies in inflammatory bowel disease. Iron is a major prooxidative agent; therefore therapeutic iron as well as heme iron from chronic mucosal bleeding can increase the iron-mediated oxidative stress in colitis by facilitating the Fenton reaction, namely production of hydroxyl radicals. In the present study colitis was induced in the iodoacetamide rat model. Forty male Whistar rats were divided into four groups, each group receiving a different diet regimen in parallel with colitis induction: Malondialdehyde was measured to assess the degree of tissue oxidative stress. There were microscopic changes, and significantly more severe colitis was seen in colonic biopsies when iron was supplemented. It was concluded that iron supplementation can amplify the inflammatory response and enhance the subsequent mucosal damage in a rat model of colitis. We suggest that the resultant oxidative stress generated by iron supplementation leads to the extension and propagation of crypt abscesses. Topics: Animals; Colitis; Dietary Supplements; Intestinal Mucosa; Iron, Dietary; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Wistar | 2000 |
Impaired nitrergic innervation in rat colitis induced by dextran sulfate sodium.
The pathophysiological role of neuronal nitric oxide synthase (nNOS) in colitis remains unknown.. We investigated colonic transit, nonadrenergic, noncholinergic (NANC) relaxation, nNOS activity, and nNOS synthesis in the myenteric plexus in dextran sulfate sodium (DSS)-induced colitis in rats.. Oral administration of 5% DSS for 7 days induced predominant distal colitis and delayed colonic transit. In the proximal colon, carbachol-, sodium nitroprusside-, and electrical field stimulation (EFS)-induced responses were not different between control and DSS-treated rats. In the distal colon, EFS-evoked cholinergic contraction, NANC relaxation, and orphanin FQ-induced contraction were significantly impaired in DSS-treated rats compared with those in control rats, but carbachol- and sodium nitroprusside-induced responses remained intact in DSS-treated rats. The number of nNOS-immunopositive cells, catalytic activity of NOS, and nNOS synthesis in the colonic wall were significantly reduced in the distal colon of DSS-treated rats. In contrast, the number of PGP 9.5-immunopositive cells and PGP 9.5 synthesis in the colonic wall remained intact in the distal colon of DSS-treated rats.. These results suggest that impaired NANC relaxation in the distal colon is associated with reduced activity and synthesis of nNOS in the myenteric plexus in DSS-induced colitis. Topics: Animals; Blotting, Western; Catalysis; Colitis; Colon; Dextran Sulfate; Gastrointestinal Motility; Gastrointestinal Transit; Immunohistochemistry; Male; Nitric Oxide Synthase; Nitric Oxide Synthase Type I; Peroxidase; Rats; Rats, Sprague-Dawley; Thiolester Hydrolases; Ubiquitin Thiolesterase | 2000 |
Neuromuscular dysfunction in the jejunum and colon of human leukocyte antigen B27 transgenic rats.
HLA-B27 transgenic rats are a model of spontaneous gastrointestinal inflammation associated with expression of human leukocyte antigen (HLA) B27 and beta(2)-microglobulin. Our goal was to investigate in vitro enteric nerve regulation and contractile activity in isolated longitudinal muscles from the jejunum and colon of HLA-B27 rats. Nontransgenic age-matched Fisher 344 rats were used as controls. Intestinal inflammation and tissue injury, quantified histologically and through tissue myeloperoxidase activity, were evident in both the jejunum and colon of HLA-B27 rats. Although resting tension and spontaneous activity of the jejunal and colonic muscles from HLA-B27 rats did not differ significantly from controls, responses to both enteric nerve stimulation or direct muscle activation were significantly inhibited. In muscles from HLA-B27 rats, electrical field stimulation (0.5 ms, 0.5-20 Hz) induced low-amplitude contractions (maximal reduction 60-65%) compared with respective controls. In the presence of atropine and guanethidine, nonadrenergic and noncholinergic contractile responses to higher frequencies of stimulation (8-20 Hz) were also of lower amplitude. These changes were accompanied by a shift in neurally mediated contractions from predominantly cholinergic in the jejunum and colon of Fisher 344 rats to predominantly nonadrenergic and noncholinergic in HLA-B27 rats. Furthermore, maximal contractions to carbachol or KCl depolarization were reduced (up to 2.7-fold) compared with respective controls. In the jejunum of HLA-B27 rats the EC(50) level for carbachol was decreased. The data indicate that gastrointestinal inflammation induced by expression of HLA-B27 is associated with hypocontractility and inhibition of enteric cholinergic control of the longitudinal muscle in both the small and large intestine. Topics: Adrenergic Agents; Animals; Animals, Genetically Modified; Atropine; Carbachol; Colitis; Electric Stimulation; Enteritis; Guanethidine; HLA-B27 Antigen; In Vitro Techniques; Jejunal Diseases; Male; Muscarinic Agonists; Muscarinic Antagonists; Muscle, Smooth; Neuromuscular Diseases; Parasympathetic Nervous System; Peroxidase; Potassium Chloride; Rats; Rats, Inbred F344 | 2000 |
Cyclo-oxygenase-2 inhibitors ameliorate the severity of experimental colitis in rats.
Both in experimental colitis and in inflammatory bowel disease, colonic eicosanoid generation is enhanced and may contribute to the pathogenesis of the inflammatory response.. To evaluate the effect of selective cyclo-oxygenase-2 (COX-2) inhibitors on the extent and severity of two models of experimental colitis.. Colitis was induced by intra-caecal administration of 2 ml 5% acetic acid or intra-colonic administration of 0.1 ml 3% iodoacetamide. Rats were treated intra-gastrically with nimesulide 2 x 10 mg/kg/day, or once with SC-236 6 mg/kg, and killed 1 or 3 days after damage induction. The colon was isolated, weighed, macroscopic damage was measured, and mucosal samples were obtained for histology and for determination of myeloperoxidase (MPO) and nitric oxide synthase (NOS) activities and eicosanoid generation. The serum levels of thromboxane B2 (TXB2), tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) were determined.. Nimesulide significantly decreased the extent of colitis induced by acetic acid. Both nimesulide and SC-236 significantly decreased the extent of iodoacetamide-induced colonic damage. The decrease in the extent of colitis induced by nimesulide was accompanied by a significant decrease in mucosal MPO and NOS activities. Nimesulide and SC-236 decreased the enhanced colonic eicosanoid generation in acetic acid and iodoacetamide-induced colitis, and, in iodoacetamide-treated rats, nimesulide also decreased the elevated serum TNF-alpha and IL-1beta levels.. The effective nimesulide and SC-236-induced amelioration of the severity of the colitis in acetic acid and iodoacetamide-treated rats confirms the role of eicosanoids in their pathogenesis and suggests that COX-2 inhibitors may be of value in the treatment of inflammatory bowel disease. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Cyclooxygenase Inhibitors; Disease Models, Animal; Eicosanoids; Indomethacin; Inflammation; Interleukin-1; Male; Nitric Oxide Synthase; Peroxidase; Pyrazoles; Rats; Rats, Sprague-Dawley; Severity of Illness Index; Sulfonamides; Tumor Necrosis Factor-alpha | 2000 |
The COX-2 inhibitor nimesulide suppresses superoxide and 8-hydroxy-deoxyguanosine formation, and stimulates apoptosis in mucosa during early colonic inflammation in rats.
As we have shown previously [Tardieu,D., Jaeg,J.P., Cadet,J., Embvani,E., Corpet,D.E. and Petit,C. (1998) Cancer Lett, 134, 1-5], a 48-h treatment of 6% dextran sodium sulphate (DSS) in drinking water led to a reproducible 2-fold increase of the mutagenic oxidative lesion 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) in colonic mucosa DNA of rats in vivo. The aim of this study was to test the effect of nimesulide, a preferential COX-2 inhibitor, on the DSS-induced 8-oxodGuo increase. We show that nimesulide when administered orally, simultaneously with DSS at 5 mg/kg/day, not only totally prevents 8-oxodGuo formation but also suppresses the 5-fold increase of superoxide induced by DSS in the colonic mucosa. This was measured by in vivo formazan blue precipitation (P < 0.01 in the Wilcoxon test). Moreover, nimesulide enhances apoptosis by approximately 30% as compared with the already high level induced by DSS treatment (P < 0.01). It is suggested that the significant increase in mutagenic oxidative DNA damage, produced by mild acute colonic inflammation, could be important in the initiation of colon cancer in both animals and man. These effects may explain at least partly the well-documented protective action towards colon cancer by preferential COX-2 inhibitors, either xenobiotics such as nimesulide or natural nutrients. Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Colitis; Cyclooxygenase Inhibitors; Deoxyguanosine; Female; Intestinal Mucosa; Oxidative Stress; Peroxidase; Rats; Rats, Inbred F344; Sulfonamides; Superoxides | 2000 |
Innate immune responses in children and adults with Shigellosis.
An array of pro- and anti-inflammatory mediators of the innate immune system was analyzed in stool, urine, and rectal mucosa samples from adults and children with shigellosis to better understand their role in recovery from and in the immunopathogenesis of the disease. Increased concentrations of lactoferrin (Lf), myeloperoxidase (MPO), prostaglandin E(2), and leukotriene B(4) (LTB(4)) in stool during acute shigellosis in both children and adults indicated that activated cells of the innate defense system at the mucosal site were secreting the mediators. Increased concentration of MPO and 8-iso-prostaglandin F(2alpha) and lower levels of superoxide dismutase (SOD) activity in stool during acute Shigella infection suggested increased formation of reactive oxygen species, free radical-catalyzed peroxidation of membrane lipids, and decreased scavenging of the reactive oxygen radicals. In children, lower expression of SOD in tissue with severe inflammation and lower levels of SOD activity in stool for longer periods compared to adults may further worsen the tissue damage and predispose the children to a lowered defense. Both adult and pediatric patients had significantly higher expression of inducible nitric oxide synthase (iNOS) in the rectum with severe inflammation, compared to that seen with mild inflammation, accompanied by persistently up-regulated iNOS mRNA, reflecting increased production of nitric oxide at the local site. However, in contrast to adults, reduced urinary nitrate levels in pediatric patients during acute shigellosis suggested lower production of nitric oxide in the renal compartment. Persistent production of Lf in pediatric patients may contribute to chronic inflammation in the rectum. In addition, increased production of proinflammatory mediators in the rectum of patients with severe histology suggested contribution of these molecules to the immunopathogenesis of severe colitis caused by shigellae. Topics: Acute Disease; Adolescent; Adult; Age Factors; Anti-Inflammatory Agents; Child; Child, Preschool; Colitis; Convalescence; Cyclooxygenase 2; Dysentery, Bacillary; Feces; Humans; Immunity, Innate; Inflammation Mediators; Isoenzymes; Leukotrienes; Membrane Proteins; Middle Aged; Nitrates; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Nitrites; Peroxidase; Prostaglandin-Endoperoxide Synthases; Prostaglandins; RNA, Messenger; Superoxide Dismutase | 2000 |
Effects of trimetazidine on oxidant/antioxidant status in trinitrobenzenesulfonic acid-induced chronic colitis.
Trimetazidine (TMZ), an anti-ischemic agent with proposed antioxidant properties, was used in a chronic colitis model in order to evaluate its effectiveness as a therapeutic agent in chronic colitis. Treatment of male Swiss Albino rats with ethanol (50%) and trinitrobenzenesulfonic acid (TNBS) (30 mg/kg) produced colitis as evidenced by histopathologic damage and inflammatory alterations, lipid peroxidation [increased malondialdehyde (MDA) levels], and enhanced neutrophil infiltration [increased myeloperoxidase (MPO) activity] without marked change in glutathione status. Administration of TMZ (5 mg/kg) to TNBS-treated rats failed to affect the TNBS-induced changes in histopathology and MPO activities. Unexpectedly, intrarectal (i.r.) administration of TMZ significantly elevated colonic MDA levels to a greater extent than TNBS alone. Intraperitoneal (i.p.) TMZ treatment seemed to increase total glutathione (tGSH), GSH, and GSH/GSSG values. In conclusion, our results demonstrated that (a) i.r. administration of ethanol and TNBS is an effective way of inducing a chronic colitis model, (b) inflammation and lipid peroxidation augment tissue damage in the chronic colitis model, (c) i.p. TMZ treatment significantly inhibits MDA production in the chronic colitis model, (d) TMZ treatment is more effective via the i.p. compared to i.r. route, and (e) TMZ seems to show its antioxidant effect via preserving the tissue's GSH/GSSG ratios. Topics: Administration, Rectal; Animals; Chronic Disease; Colitis; Ethanol; Glutathione; Injections, Intraperitoneal; Lipid Peroxidation; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Solvents; Trimetazidine; Trinitrobenzenesulfonic Acid; Vasodilator Agents | 2000 |
Dextran sulfate sodium-induced colonic histopathology, but not altered epithelial ion transport, is reduced by inhibition of phosphodiesterase activity.
Inhibition of phosphodiesterase (PDE) activity is beneficial in models of arthritis and airway inflammation. Here we assessed the ability of PDE inhibitors to modulate colitis by exposing mice to 4% (w/v) dextran sulfate sodium (DSS) drinking water for 5 days with or without rolipram, an inhibitor of PDE type 4, or the nonselective PDE inhibitor, pentoxifylline (both at 5 mg/kg, i.p., twice daily). Controls received saline, vehicle, or drug only. Colonic histology, myeloperoxidase (MPO) and tumor necrosis factor-alpha (TNF-alpha) levels, and epithelial ion transport (baseline and stimulated by electrical nerve stimulation, carbachol, and forskolin) were examined. DSS-treated mice displayed a variable diarrhea, significant histopathology in the mid-distal colon, elevated MPO activity, and reduced (>50%) responses to all three pro-secretory stimuli. Treatment with rolipram, and to a lesser extent pentoxifylline, significantly reduced the severity of the colonic histopathology and MPO levels. Neither PDE inhibitor had any affect on the diminished ion transport events caused by DSS-induced colitis. However, although stimulated ion transport events were still reduced 3 days after DSS treatment, colonic segments from DSS + rolipram-treated mice displayed enhanced recovery in their secretory responsiveness, particularly to carbachol. These findings indicate that specific PDE4 inhibition can significantly reduce the tissue damage that accompanies colitis and enhance recovery of normal colonic function. Topics: Animals; Biological Transport; Colitis; Colon; Cytokines; Dextran Sulfate; Epithelium; Intestinal Mucosa; Ions; Male; Mice; Mice, Inbred BALB C; Pentoxifylline; Peroxidase; Phosphodiesterase Inhibitors; Recovery of Function; Rolipram | 2000 |
Relation between colonic inflammation severity and total low-molecular-weight antioxidant profiles in experimental colitis.
Tissue antioxidant status is altered as a response to oxidative stress. This oxidative stress, caused by reactive oxygen species, is associated with inflammatory bowel disease (IBD). Our aim was to examine the relationship between total tissue low-molecular-weight antioxidant (LMWA) profile and inflammation severity in dinitrobenzene sulfonic acid (DNBS) experimental colitis in the rat. Rats were treated with three doses of DNBS: 1, 10, and 20 mg. Inflammation severity was assessed by tissue colonic wet weight, macroscopic evaluation, and tissue myeloperoxidase (MPO) activity. The capacity of water-soluble LMWA was assessed by measuring the reducing power of the tissues with cyclic voltammetry (CV) and by measuring tissue levels of reduced glutathione. While typical markers of inflammation (MPO, macroscopic examination, and colonic wet weight) indicated DNBS dose dependency, such dependency could not be demonstrated for the tissue LMWA as measured by reduced glutathione levels and by the tissues' reducing power. Mild colonic inflammation (induced by ethanol or by 1 mg of DNBS) caused an increase in the overall capacity of water-soluble LMWA. However, severe inflammation (induced by 20 mg of DNBS) caused a reduction in the tissue LMWA capacity. An intermediate dose of DNBS (10 mg) caused moderate inflammation, but did not cause a significant change in the tissue LMWA compared with a saline control treatment. In conclusion, LMWA changed in a biphasic pattern reflective of the severity of mucosal colonic inflammation. It is suggested that: low dose of DNBS (1 mg) and topical alcohol (25% v/v) caused an adaptation effect to the mild oxidative stress associated with mild inflammation. This resulted in an increase in the LMWA. A higher dose of DNBS (20 mg) caused more severe inflammation with an overall reduction in LMWA. The increased efflux of reactive oxygen species, associated with severe inflammation, led to an overall consumption of the tissue LMWA, which masked the increase in LMWA caused by the mild oxidative stress. Topics: Animals; Antioxidants; Colitis; Colon; Dinitrofluorobenzene; Dose-Response Relationship, Drug; Electrophysiology; Glutathione; Intestinal Mucosa; Male; Molecular Weight; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species | 2000 |
Spontaneously developing chronic colitis in IL-10/iNOS double-deficient mice.
Mice deficient in both inducible nitric oxide synthase (iNOS) and interleukin (IL)-10 (iNOS(-/-)/IL-10(-/-)) were created to examine the role of iNOS in spontaneously developing intestinal inflammation. IL-10(-/-)/iNOS(-/-) mice were compared with IL-10(-/-) (iNOS(+/+)) littermates over 6 mo. RT-PCR, Western blot analysis, and immunohistochemistry were performed to measure iNOS message and protein levels. Plasma nitrate/nitrite (NO(x)) levels were assessed by HPLC. Damage scores (macroscopic and microscopic) and granulocyte infiltration were assessed. At 3-4 wk, IL-10(-/-) and IL-10(-/-)/iNOS(-/-) mice had no signs of colonic inflammation or granulocyte infiltration. Plasma NO(x) levels were not different from controls. By 3-4 mo, IL-10(-/-) mice had increased damage scores and granulocyte infiltration concurrent with increased mRNA and protein synthesis (restricted to the epithelium) for iNOS in intestinal tissues but not other tissues. Plasma NO(x) levels increased fivefold. Interestingly, in the absence of iNOS induction or increased plasma NO(x), iNOS(-/-)/IL-10(-/-) mice had damage and granulocyte infiltration equivalent to those observed in IL-10(-/-) littermates. These data suggest that iNOS does not impact on the development or severity of spontaneous chronic inflammation in IL-10-deficient mice. Topics: Age Factors; Animals; Blotting, Western; Chronic Disease; Colitis; Colon; Female; Fluorescent Antibody Technique; Gene Expression Regulation, Enzymologic; Interleukin-10; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Nitrites; Peroxidase; RNA, Messenger | 2000 |
Cyclooxygenase-2-derived prostaglandin D(2) is an early anti-inflammatory signal in experimental colitis.
The ability of nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors to exacerbate inflammatory bowel disease suggests that prostaglandins are important anti-inflammatory mediators in this context. Prostaglandin D(2) has been suggested to exert anti-inflammatory effects. We investigated the possibility that prostaglandin D(2) derived from cyclooxygenase-2 plays an important role in downregulating colonic inflammation in rats. Colitis was induced by intracolonic administration of trinitrobenzene sulfonic acid. At various times thereafter (from 1 h to 7 days), colonic prostaglandin synthesis and myeloperoxidase activity (index of granulocyte infiltration) were measured. Prostaglandin D(2) synthesis was elevated >4-fold above controls within 1-3 h of induction of colitis, preceding significant granulocyte infiltration. Treatment with a selective cyclooxygenase-2 inhibitor abolished the increase in prostaglandin D(2) synthesis and caused a doubling of granulocyte infiltration. Colonic granulocyte infiltration was significantly reduced by administration of prostaglandin D(2) or a DP receptor agonist (BW-245C). These results demonstrate that induction of colitis results in a rapid increase in prostaglandin D(2) synthesis via cyclooxygenase-2. Prostaglandin D(2) downregulates granulocyte infiltration into the colonic mucosa, probably through the DP receptor. Topics: Animals; Blotting, Western; Celecoxib; Colitis; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Disease Models, Animal; Gene Expression Regulation, Enzymologic; Hydantoins; Indomethacin; Intramolecular Oxidoreductases; Isoenzymes; Lipocalins; Male; Necrosis; Neutrophils; Peroxidase; Peroxisomes; Prostaglandin D2; Prostaglandin-Endoperoxide Synthases; Pyrazoles; Rats; Rats, Wistar; Receptors, Cytoplasmic and Nuclear; Receptors, Immunologic; Receptors, Prostaglandin; RNA, Messenger; Sulfonamides; Transcription Factors | 2000 |
The effect of berberine chloride on experimental colitis in rats in vivo and in vitro.
Berberine is an isoquinoline alkaloid with multiple pharmacological actions, including anti-inflammatory activity. The aims of this study were to examine the effect of berberine on the mucosal healing process and to investigate whether berberine can inhibit the increased production of interleukin-8 in trinitrobenzene sulfonic acid-induced colitis in rats. Berberine was administered orally for 3 days or 1 week at a dosage of 7.5 or 15 mg/kg/day. Tissue damage scores, body weight, colon wet weight, and colon wall thickness were measured, and myeloperoxidase activity in colon tissue was also examined. Histological lesions, morphological damage, and myeloperoxidase activity were reduced after 1 week of treatment with berberine at a dosage of 15 mg/kg/day. Furthermore, 1 week after trinitrobenzene sulfonic acid treatment, the production of interleukin-8 by cultured rectal mucosa or cardiac blood mononuclear cells with or without stimulation of lipopolysaccharide for 24 h was also analyzed by enzyme-linked immunosorbent assay. Cardiac blood mononuclear cells and rectal mucosa of normal rats produced substantial amounts of interleukin-8, which increased strikingly with the stimulation of lipopolysaccharide. Cardiac blood mononuclear cells and rectal mucosa of trinitrobenzene sulfonic acid-treated rats secreted more interleukin-8 than those of normal rats. The addition of berberine with a concentration of 10(-5) M to the culture media resulted in an inhibition of interleukin-8 production of rectal mucosa. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Berberine; Cells, Cultured; Colitis; Colon; Interleukin-8; Intestinal Mucosa; Leukocytes, Mononuclear; Male; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Rectum; Trinitrobenzenesulfonic Acid | 2000 |
The tyrosine kinase inhibitor tyrphostin AG 126 reduced the development of colitis in the rat.
Inflammatory bowel disease is characterized by oxidative and nitrosative stress, leukocyte infiltration, up-regulation of the expression of intercellular adhesion molecule-1 (ICAM-1), and up-regulation of P-selectin in the colon. Here we investigate the effects of the tyrosine kinase inhibitor, Tyrphostin AG 126, in rats subjected to experimental colitis. Colitis was induced in rats by intracolonic instillation of dinitrobenzene sulfonic acid (DNBS). Rats experienced hemorrhagic diarrhea and weight loss. Four days after administration of DNBS, the mucosa of the colon exhibited large areas of necrosis. Neutrophil infiltration (determined by histology as well as an increase in myeloperoxidase activity in the mucosa) was associated with up-regulation of ICAM-1 and P-selectin, as well as high tissue levels of malondialdehyde. Immunohistochemistry for nitrotyrosine and poly(ADP-ribose) polymerase showed an intense staining in the inflamed colon. Staining with an anti-COX-2 antibody of sections of colon obtained from DNBS-treated rats showed a diffuse staining of the inflamed tissue. Furthermore, expression of inducible nitric oxide synthase was found mainly in macrophages located within the inflamed colon of DNBS-treated rats. Tyrphostin AG 126 (5 mg/kg daily ip) significantly reduced the degree of hemorrhagic diarrhea and weight loss caused by administration of DNBS. Tyrphostin AG 126 also caused a substantial reduction of (1) the phosphorylation of tyrosine residues of proteins (immunoblots of inflamed colon), (2) the degree of colonic injury, (3) the rise in myeloperoxidase activity (mucosa), (4) the increase in the tissue levels of malondialdehyde, (5) the increase in staining (immunohistochemistry) for nitrotyrosine and poly(ADP-ribose) polymerase, as well as (6) the up-regulation of ICAM-1 and P-selectin caused by DNBS in the colon. Thus, we provide the first evidence that the tyrosine kinase inhibitor Tyrphostin AG126 reduces the degree of colitis caused by DNBS. Topics: Animals; Body Weight; Colitis; Cyclooxygenase 2; Cytokines; Enzyme Inhibitors; Isoenzymes; Lipid Peroxidation; Male; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Prostaglandin-Endoperoxide Synthases; Protein-Tyrosine Kinases; Rats; Rats, Sprague-Dawley; Tyrosine; Tyrphostins | 2000 |
Rebamipide, an antiulcer drug, prevents DSS-induced colitis formation in rats.
This study was conducted to investigate the efficacy of rebamipide against experimental colitis induced by dextran sulfate sodium (DSS) in a rat model of inflammatory bowel disease. Experimental colitis was induced in male Wistar rats by oral administration of 3% DSS solution for one week. The rats were provided with standard diet containing 0.105% rebamipide (160 mg/kg/day) for 1 week. In rats treated with rebamipide, clinical (body weight loss, bloody diarrhea, reduced physical activity, severe anemia, shortened colonic length, and perianal injury) and histopathological (pathological lesion score) findings of DSS colitis were significantly less than in rats with DSS colitis not treated with rebamipide. Rebamipide thus inhibited the induction of colitis. Rebamipide significantly reduced concentrations of both interleukin-1alpha and GRO/CINC-1 (IL-8-like substance) and cell infiltrates in colonic wall, in parallel with decreased activity of myeloperoxidase. It also reduced expression of IL-1 mRNA but did not influence expression of GRO/CINC-1 mRNA. The attenuation of colonic indices of colitis by rebamipide in this rat model suggests that this drug might have beneficial effects in the treatment of human ulcerative colitis. These effects of rebamipide are attributable to its inhibition of inflammatory cytokine-mediated granulocyte (neutrophil) infiltration into the colon. Topics: Alanine; Animals; Anti-Ulcer Agents; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Interleukin-1; Interleukin-8; Male; Peroxidase; Quinolones; Rats; Rats, Wistar | 2000 |
Tempol, a membrane-permeable radical scavenger, reduces dinitrobenzene sulfonic acid-induced colitis.
Inflammatory bowel disease is characterized by oxidative and nitrosative stress, leukocyte infiltration, and up-regulation of intercellular adhesion molecule 1 (ICAM-1) expression in the colon. The aim of the present study was to examine the effects of tempol, a membrane-permeable radical scavenger, in rats subjected to experimental colitis. Colitis was induced in rats by intracolonic instillation of dinitrobenzene sulfonic acid. Rats experienced bloody diarrhea and significant loss of body weight. At 4 days after the administration of dinitrobenzene sulfonic acid, the colon injury comprised of large areas of mucosal necrosis. Neutrophil infiltration (measured as increase in myeloperoxidase activity in the mucosa) was associated with up-regulation of ICAM-1 and expression of P-selectin and high levels of malondialdehyde (an indicator of lipid peroxidation). Immunohistochemistry for nitrotyrosine and poly (ADP-ribose) synthetase showed an intense staining in the inflamed colon. Treatment of rats with tempol (15 mg/kg daily i.p.) significantly reduced the appearance of diarrhea and the loss in body weight. This was associated with a remarkable amelioration of the disruption of the colonic architecture as well as a significant reduction in the degree of both neutrophil infiltration and lipid peroxidation in the inflamed colon. Tempol also reduced the appearance of nitrotyrosine and poly (ADP-ribose) synthetase immunoreactivity in the colon as well as the up-regulation of ICAM-1 and P-selectin. The results of this study suggest that membrane-permeable radical scavengers, such as tempol, exert beneficial effects in experimental colitis and may, hence, be useful in the treatment of inflammatory bowel disease. Topics: Animals; Benzenesulfonates; Body Weight; Cell Membrane Permeability; Colitis; Colon; Cyclic N-Oxides; Free Radical Scavengers; Immunohistochemistry; Intestinal Mucosa; Lipid Peroxidation; Male; Neutrophil Infiltration; Organ Size; Peroxidase; Poly(ADP-ribose) Polymerases; Rats; Rats, Sprague-Dawley; Spin Labels; Spleen; Survival Rate; Tyrosine | 2000 |
The effect of local attachment of cationized antioxidant enzymes on experimental colitis in the rat.
To investigate the possibility of local treatment of colitis with the adhesive antioxidant enzymes catalase and superoxide dismutase (SOD).. The net electric charge of the enzymes' surfaces was modified from negative to positive, to cause their adherence to the colon epithelium. The effects of this local administration were assessed in inflamed rat colon. Inflammation severity (colitis) was assessed by measuring colonic tissue myeloperoxidase (MPO) activity, amounts of tumour necrosis factor alpha (TNFalpha) and concentrations of reduced glutathione (GSH). The measurements were carried out in two types of protocols: preventive (pre-colitis induction) and treatment (post-colitis induction). In addition, the efficacy of treatment with the cationized enzymes was compared to 5-aminosalicylic acid (5-ASA) and betamethasone with similar administration routes.. The two cationized antioxidant enzymes were found to be efficient in both prevention and treatment of experimental colitis. The two cationized enzymes caused a significant reduction in MPO activity. A reduction in TNFalpha concentration was noted only after the treatment protocol. No correlation was found between inflammation severity and tissue levels of GSH. In most cases the cationized enzymes were more effective than 5-ASA and betamethasone.. Cationized catalase and cationized SOD have the potential to be efficient therapeutic tools in the local treatment of colitis. Topics: Animals; Anti-Inflammatory Agents; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Betamethasone; Catalase; Cations; Colitis; Free Radical Scavengers; Glutathione; Intestinal Mucosa; Male; Mesalamine; Peroxidase; Rats; Rats, Sprague-Dawley; Serum Albumin, Bovine; Superoxide Dismutase; Tumor Necrosis Factor-alpha | 2000 |
Activation of mucosal phospholipase D in a rat model of colitis.
Phospholipase D (PLD) hydrolyzes phosphatidylcholine and produces lipid second messengers. Although cellular PLD has recently been recognized as an important signal-transmitting enzyme, the role of PLD in pathophysiologic conditions is largely unknown. In particular, the regulation of PLD in intestinal inflammation has not been previously investigated. The aim of the present study was to elucidate the role of PLD in experimental colitis.. Rats were intracolonically administered acetic acid and assessed for mucosal damage, mucosal PLD activity, mucosal myeloperoxidase activity, mucosal chemiluminescence and luminal concentration of leukotriene B4. Acetic acid treatment induced acute mucosal injury that was maximal at 24 h after treatment.. Mucosal PLD activity was significantly elevated and correlated with mucosal damage. Chemiluminescence in colitic mucosa was inhibited by the addition of ethanol which suppresses the formation of phosphatidic acid catalyzed by PLD.. These results suggest that PLD is activated in experimental colitis in rats and that PLD may play a role in mucosal damage induced by reactive oxygen metabolites. Topics: Acetates; Acute Disease; Animals; Central Nervous System Depressants; Colitis; Colon; Data Interpretation, Statistical; Disease Models, Animal; Enzyme Activation; Ethanol; Female; Immunoenzyme Techniques; Intestinal Mucosa; Leukotriene B4; Luminescent Measurements; Peroxidase; Phospholipase D; Phospholipids; Rats; Rats, Wistar; Time Factors | 2000 |
Increased expression of epidermal growth factor-receptor in an experimental model of colitis in rats.
Epidermal growth factor and related proteins share some structural homology and bind to one common receptor. We have shown previously that exogenously applied EGF protects colonic mucosa against injury in an experimental model of colitis in rats and that the endogenously expressed ligands for the EGF-receptor are predominantly transforming growth factor alpha precursors. The aim of our present study was to evaluate the EGF-receptor expression in response to mucosal injury in the same model of colitis.. The trinitrobenzene sulphonic acid (TNBS)/ethanol-induced model of colitis in rats was used and EGF-receptor expression was evaluated using ribonuclease protection assay and Western blot analysis. The extent of mucosal injury and inflammation was characterized by using a microscopic and macroscopic damage score and by estimation of the myeloperoxidase activity in colonic specimens.. Irritation of the colonic mucosa leads to severe colonic inflammation with tissue oedema, erosions and mucosal ulcers and to a significant increase in myeloperoxidase activity expressed by neutrophil granulocytes and macrophages. A significant increase in EGF-receptor mRNA expression was obtained at 8-24 h followed by an increased expression of the EGF-receptor protein at 1-5 days after the induction of colitis. On Western blot analysis only one immunoreactive band with a molecular weight of approximately 170 kDa was detected.. Mucosal inflammation leads to a significant increase in the EGF-receptor expression in the early phases of colitis. These findings support our hypothesis that EGF and related proteins and their common receptor play a pivotal role in mucosal defence and repair. Topics: Actins; Animals; Blotting, Western; Colitis; Colon; ErbB Receptors; Male; Nuclease Protection Assays; Peroxidase; Rats; Rats, Sprague-Dawley; RNA, Messenger | 2000 |
Expression of ICAM-1 and acute inflammatory cell infiltration in the early phase of radiation colitis in rats.
Inflammatory cell infiltration of the colon is observed at an early stage of radiation-induced colitis. The emigration of inflammatory cells from the circulation requires interactions between cell adhesion molecules on the vascular endothelium and molecules on the surface of leukocytes. To elucidate this process, the present work analyzes the kinetics of the expression of intercellular adhesion molecule-1 (ICAM-1) and the accumulation of inflammatory myeloperoxidase (MPO)-positive cells in relation to the appearance of acute radiation colitis prior to an overt radiation-induced ulcer. Colon tissues were obtained from Wistar Kyoto rats at various times after 22.5 Gy irradiation to the rectum. Histologically, crypt depletion and numerous inflammatory cells were observed 4 days after irradiation, and mucosal ulcer 6 days after irradiation. ICAM-1 immunopositivity was present in the endothelial cells of small vessels in the mucosa of both control and irradiated rats. ICAM-1 mRNA expression was detected in normal colon and irradiated colon by reverse transcription-PCR. In Northern blotting, ICAM-1 mRNA levels were found to increase markedly in the irradiated colon compared to the normal colon. In Western blotting. ICAM-1 protein expression also increased with a peak one day after irradiation, and remained elevated up to 6 days thereafter. The number of MPO-positive cells in lamina propria mucosa increased in a time-dependent fashion from 6 h to 6 days after irradiation. These data suggest that up-regulation of ICAM-1 in endothelial cells and accumulation of MPO positive cells play important roles in the development of radiation-induced colonic ulcer. Topics: Animals; Cell Movement; Colitis; Inflammation; Intercellular Adhesion Molecule-1; Leukocytes; Male; Peroxidase; Radiation Injuries, Experimental; Rats; Rats, Inbred WKY | 2000 |
Oral administration of avian tumor necrosis factor antibodies effectively treats experimental colitis in rats.
Tumor necrosis factor (TNF) is implicated in the pathogenesis of inflammatory bowel disease. Clinical trials indicate that intravenous infusion of anti-TNF antibody is an effective therapy for Crohn's disease. An oral anti-TNF therapy may be a preferred approach, reducing systemic side effects and eliminating the inconvenience and expense of administering infusions. We tested oral avian anti-TNF antibodies in the acute and chronic phases of a rodent colitis model. Efficacy was compared to sulfasalazine and dexamethsone. Rats with chemically induced colitis were treated orally with anti-TNF antibody, placebo, or comparator. Efficacy was assessed by change in colonic weight, morphology, histology, and tissue myeloperoxidase activity. Oral anti-TNF antibody, in both the acute and chronic phases of the model, significantly decreased all inflammatory end points and proved to be more effective than sulfasalazine and dexamethasone. Oral delivery of avian anti-TNF antibodies is an effective treatment of experimental colitis and may provide advantages to current parenteral anti-TNF antibodies. Topics: Administration, Oral; Animals; Antibodies; Chickens; Colitis; Dexamethasone; Disease Models, Animal; Female; Immunoglobulins; Immunohistochemistry; Peroxidase; Rats; Rats, Sprague-Dawley; Sulfasalazine; Tumor Necrosis Factor-alpha | 2000 |
Effect of N-acetylcysteine on colitis induced by acetic acid in rats.
(1) To verify the proposed role of reactive oxygen species (ROS) in ulcerative colitis, the effect of an antioxidant N-acetylcysteine (NAC) was studied in acetic acid (AA)-induced colonic inflammation. (2) Depending on the dose used, NAC administered intracolonically was found to reduce the extent of colonic damage, along with a decrease in myeloperoxidase (MPO) activity, colonic wet weight and wet/dry weight ratio. (3) NAC attenuated the enhanced vascular permeability and prevented the depletion of colonic reduced glutathione (GSH) caused by AA administration. (4) The findings indicate that NAC may prove beneficial in the treatment of colitis. Topics: Acetic Acid; Acetylcysteine; Animals; Colitis; Dose-Response Relationship, Drug; Glutathione; Male; Peroxidase; Rats; Rats, Wistar; Reactive Oxygen Species | 2000 |
Blockade of Poly(ADP-ribose) synthetase inhibits neutrophil recruitment, oxidant generation, and mucosal injury in murine colitis.
Inflammatory bowel disease is characterized by oxidative and nitrosative stress, leukocyte infiltration, and up-regulation of intercellular adhesion molecule 1 (ICAM-1) expression in the colon. Recent data show that oxidative and nitrosative stress in isolated enterocytes produces DNA single-strand breaks that activate the nuclear enzyme poly(ADP-ribose) synthetase (PARS), resulting in depletion of intracellular energetics and increased paracellular permeability. The aim of the present study was to examine the in vivo relevance of this injury pathway.. Colitis was induced by rectal instillation of trinitrobenzenesulfonic acid (TNBS) in mice with a genetic deficiency of PARS (PARS-/-) and in wild-type littermates.. In wild-type mice, TNBS treatment resulted in colonic erosion and ulceration that was maintained up to 7 days. Neutrophil infiltration (indicated by myeloperoxidase activity in the mucosa) was associated with up-regulation of ICAM-1 and high levels of malondialdehyde and nitrotyrosine. TNBS-treated PARS-/- mice experienced a similar colonic injury that was, however, completely resolved by 6 days. Resolution of the damage was associated with absence of ICAM-1 up-regulation, reduction of neutrophil infiltration, lipid peroxidation, and nitrosative damage.. These data show that PARS plays a critical role in colonic inflammation possibly by regulating ICAM-1 expression, neutrophil recruitment, and the subsequent oxidant generation. Topics: Animals; Colitis; Disease Models, Animal; Immunohistochemistry; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Malondialdehyde; Mice; Neutrophils; Oxidative Stress; Permeability; Peroxidase; Poly(ADP-ribose) Polymerase Inhibitors; Severity of Illness Index; Time Factors; Trinitrobenzenesulfonic Acid; Tyrosine; Up-Regulation | 1999 |
Protein kinase C mediates experimental colitis in the rat.
Protein kinase C (PKC) plays an important role in the cell signal transduction of many physiological processes. In contrast to these physiological responses, increases in PKC activity have also been associated with inflammatory disease states, including ulcerative colitis. The objective of this study was to examine the role of PKC as a causative mediator in initiation of experimentally induced colitis in the rat. Colitis was induced in rats by intrarectal (0.6 ml) instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS; 75 mg/kg in 50% ethanol) or the PKC activator phorbol 12-myristate 13-acetate (PMA; 1.5-3.0 mg/kg in 20% ethanol). Gross and histological mucosal damage, mucosal neutrophil infiltration, mucosal PKC activity, and PKC protein content for PKC isoforms alpha, beta, delta, and epsilon were assessed 2 h to 14 days after an inflammatory challenge. Both PKC activity and mucosal injury increased significantly within 4 h of TNBS treatment. PKC activity was maximal at 7 days and declined at 14 days, whereas mucosal damage became maximal at 1 day and declined after 7 days. In contrast, neutrophil infiltration as assessed by myeloperoxidase activity only increased 12 h after TNBS treatment, became maximal 1 day after TNBS administration, and declined thereafter. PKCbeta, -delta, and -epsilon were increased in response to TNBS, whereas PKCalpha protein content was decreased. The PKC antagonists staurosporine and GF-109203X (25 ng/kg iv) reduced TNBS-induced changes in mucosal PKC activity and the degree of mucosal damage. In contrast, neutropenia induced by antineutrophil serum treatment did not significantly affect the degree of injury or mucosal PKC activity. Furthermore, activation of mucosal PKC activity with PMA also induced mucosal damage, which was also inhibited by pretreatment with a PKC antagonist. In conclusion, these results suggest that increases in PKC activity play a causative role in TNBS-induced colitis. The PKC-mediated response to TNBS does not appear to involve neutrophil infiltration. Topics: Animals; Colitis; Colon; Enzyme Inhibitors; Ethanol; Indoles; Intestinal Mucosa; Isoenzymes; Male; Maleimides; Neutropenia; Peroxidase; Protein Kinase C; Rats; Rats, Sprague-Dawley; Staurosporine; Tetradecanoylphorbol Acetate; Trinitrobenzenesulfonic Acid | 1999 |
Altered myoelectrical activity in noninflamed ileum of rats with colitis induced by trinitrobenzene sulphonic acid.
Changes in gastric emptying and orocaecal transit time in patients with ulcerative colitis suggest that disturbances in gut motility may not be restricted to inflamed sites. This study sought to characterize changes in the motility of noninflamed ileum in a rat colitis model and to explore the mechanism(s) potentially involved. The myoelectrical activity of the ileum was recorded in rats with trinitrobenzene sulphonic acid (TNBS)-induced colitis. The degree of ileal and colonic inflammation was assessed by quantification of macroscopic damage and myeloperoxidase activity (MPO). The effect on ileal motility of pretreatment with atropine, indomethacin and NG-nitro-L-arginine-methyl ester (L-NAME) was investigated. TNBS-induced inflammation was restricted to the distal colon, as evidenced by morphological scores and MPO. Colitis was associated with increased frequency of ileal migrating motor complexes, characterized mainly by a decrease in the duration of phases I and III. The occurrence of ileal giant migrating complexes remained unchanged. The myoelectrical changes observed in the ileum persisted after treatment with atropine, indomethacin and L-NAME. Distal colitis is associated with abnormal myoelectrical activity in the noninflamed ileum of rats. Neither acetylcholine nor prostaglandins and nitric oxide seem to be involved. Topics: Animals; Atropine; Colitis; Colon; Electromyography; Enzyme Inhibitors; Ileum; Indomethacin; Male; Myoelectric Complex, Migrating; NG-Nitroarginine Methyl Ester; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 1999 |
Inflammatory modulation of calcium-activated potassium channels in canine colonic circular smooth muscle cells.
The characteristics of colonic circular smooth muscle slow waves are altered during inflammation. The aim of this study was to examine whether inflammation modulates the open-state probability of Ca2+-activated K+ (KCa) channels in these cells to contribute to these alterations.. The experiments were performed on freshly dissociated single smooth muscle cells from the canine colon using standard patch clamp methods. Inflammation was induced by mucosal exposure to ethanol and acetic acid.. Inflammation decreased the open-state probability of large-conductance KCa (BK) channels in the cell-attached and excised inside-out configurations. The voltage sensitivity of the channels was also reduced during inflammation. Inflammation had no significant effect on the large, medium, and small conductances or the unitary current levels of channel openings. However, it decreased the maximum number of simultaneous channel openings. The channels were Ca2+-dependent and were blocked by tetraethylammonium and charybdotoxin in normal and inflamed cells.. Inflammation decreases the open-state probability of BK channels. This may partially reverse the decrease in duration and amplitude of slow waves and depolarization of membrane potential seen in inflammation. Topics: Animals; Calcium; Colitis; Colon; Dogs; Muscle, Smooth; Peroxidase; Potassium Channels; Probability | 1999 |
Susceptibility of Lewis and Fischer rats to stress-induced worsening of TNB-colitis: protective role of brain CRF.
We assessed the role of central corticotropin-releasing factor (CRF) in stress-induced worsening of colitis in inbred rat strains with hypo (Lewis/N) and hyper (Fischer344/N) CRF responses to stress. Intracolonic administration of 2,4,6-trinitrobenzenesulfonic acid (TNB) induced colitis of similar severity in both strains as assessed on day 7 by macroscopic scoring, histological evaluation, tissue myeloperoxidase (MPO) activity, and decrease in food intake and body weight. Colitis was inhibited by daily intracerebroventricular injections of CRF in both strains. Chronic stress (3 h/day, water avoidance or wrap restraint on alternate days for 6 days) aggravated colitis more in Lewis than Fischer rats (71 and 22% further increase in MPO activity, respectively). The CRF antagonist astressin injected intracerebroventricularly enhanced the colitis response to stress and caused mortality in both strains. Fischer rats had higher plasma corticosterone levels 20 min after stress alone on day 1 and after TNB plus stress on days 1 and 3 compared with Lewis. These data show that central CRF restrains the proinflammatory action of stress in experimental colitis. Topics: Animals; Cerebral Ventricles; Colitis; Colon; Corticosterone; Corticotropin-Releasing Hormone; Female; Genetic Predisposition to Disease; Injections, Intraventricular; Intestinal Mucosa; Neuroprotective Agents; Peptide Fragments; Peroxidase; Rats; Rats, Inbred F344; Rats, Inbred Lew; Species Specificity; Stress, Psychological; Trinitrobenzenesulfonic Acid | 1999 |
Trefoil peptide TFF2 (spasmolytic polypeptide) potently accelerates healing and reduces inflammation in a rat model of colitis.
The trefoil peptides are major secretory products of mucus cells of the gastrointestinal tract and show increased expression after inflammatory or ulcerative damage. Recombinant human TFF2 (spasmolytic polypeptide) has been shown to be cytoprotective, and enhances repair in models of gastric injury.. To test the healing effects of recombinant human (h)TFF2 in a rat model of chronic colitis.. Colitis was induced by intracolonic administration of dinitrobenzene sulphonic acid in ethanol. Mucosal repair was quantified macroscopically, microscopically by image analysis of tissue histology, and by measuring myeloperoxidase activity.. Initial validation studies showed that maximal injury and inflammation occurred at the end of the first week after colitis induction (active phase), and that spontaneous healing was complete by eight weeks. Once daily intrarectal application of hTFF2 (2.5 mg/kg; approximately 0.5 mg/rat) for five days after maximal damage had been sustained, reduced both microscopic and macroscopic injury by 80% and inflammatory index by 50% compared with vehicle controls. In addition, endogenous concentrations of rat TFF2 and TFF3 (intestinal trefoil factor) were increased in the active phase of colitis and were reduced to basal levels by hTFF2 treatment.. This study has shown that hTFF2 enhances the rate of colonic epithelial repair, and reduces local inflammation in a rat model of colitis, and suggests that luminal application of trefoil peptides may have therapeutic potential in the treatment of inflammatory bowel disease. Topics: Administration, Rectal; Animals; Benzenesulfonates; Chronic Disease; Colitis; Disease Models, Animal; Ethanol; Growth Substances; Humans; Male; Mucins; Muscle Proteins; Neuropeptides; Peptides; Peroxidase; Rats; Rats, Wistar; Recombinant Proteins; Trefoil Factor-2; Trefoil Factor-3 | 1999 |
Lack of beneficial effect of COX-2 inhibitors in an experimental model of colitis.
Expression of the COX-2 enzyme has been reported in animal models of inflammatory bowel disease (IBD) as well as in patients affected by ulcerative colitis and Crohn's disease. Recently, selective inhibitors of COX-2 have become available. In this study we have evaluated three highly selective COX-2 inhibitors, NS-398, SC-58125 and PD-138387, on the trinitro-benzene sulfonic acid (TNBS) model of colitis in rats. Daily oral administration of the three compounds evaluated up to a dose of 100 mg/kg failed to significantly modify any of the parameters evaluated. Our data show that despite their potent extraintestinal antiinflammatory activity, COX-2 inhibitors do not seem to have any beneficial effect in TNBS colitis and raise the question whether this therapeutic approach would be beneficial in patients with IBD. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Dinoprostone; Isoenzymes; Male; Nitrobenzenes; Peroxidase; Peroxidases; Phenols; Prostaglandin-Endoperoxide Synthases; Pyrazoles; Rats; Rats, Sprague-Dawley; Sulfonamides; Thiazoles; Trinitrobenzenesulfonic Acid | 1999 |
Anti-inflammatory activity of phycocyanin extract in acetic acid-induced colitis in rats.
The anti-inflammatory effect of c-phycocyanin extract was studied in acetic acid-induced colitis in rats. Phycocyanin (150, 200 and 300 mg kg(-1) p.o.) was administered 30 min gbefore induction of colitis with enema of 1 ml of 4% acetic acid per rat. Twenty-four hours later myeloperoxidase (MPO) activity was determined as well as histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increase din the control colitis group. Also, histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increased in the control colitis group. Also, histopathological and ultrastructural studies showed inhibition in inflammatory cell infiltration and reduction to some extent in colonic damage in rats treated with phycocyanin. The probable role of antioxidative and the scavenging properties of phycocyanin against reactive oxygen species in the anti-colitic effect is discussed in this paper. To our knowledge this is the first report on the anti-inflammatory effect of phycocyanin in an experimental model of colitis. Topics: Acetic Acid; Animals; Anti-Inflammatory Agents; Colitis; Eukaryota; Male; Mesalamine; Microscopy, Electron; Peroxidase; Phycocyanin; Rats; Rats, Sprague-Dawley | 1999 |
Efficacy of keratinocyte growth factor-2 in dextran sulfate sodium-induced murine colitis.
The purpose of this study was to determine the efficacy of a novel human protein, keratinocyte growth factor-2 (KGF-2), in a model of murine colitis induced by ad libitum exposure to a 4% solution of dextran sulfate sodium (DSS) in the drinking water. Initial evaluation of KGF-2 was based on its ability to reduce weight loss, stool score, and histological score in mice exposed to DSS for 7 days. When KGF-2 (0.1-10.0 mg/kg i.p. or s.c.) was injected daily into DSS-treated mice from day 0 to 7, it significantly reduced all three parameters in a dose-response fashion, with a minimum effective dose of between 1 and 3 mg/kg. When KGF-2 was given therapeutically, starting 4 days after initiation of the 7-day DSS treatment, the 3- but not the 0.5-mg/kg dose significantly enhanced weight recovery after discontinuation of DSS treatment. When DSS treatment was prolonged beyond the normal 7 days, therapeutic intervention on day 2 or 4 also significantly reduced mortality, weight loss, and stool score at the 1- and 3-mg/kg dose. Therapeutic treatment also resulted in reduction of colon myloperoxidase levels by more than 50%. These experiments suggest that KGF-2 may be clinically useful in the treatment of inflammatory bowel diseases such as ulcerative colitis and Crohn's disease. Topics: Animals; Body Weight; Colitis; Colon; Dextran Sulfate; Feces; Female; Fibroblast Growth Factor 10; Fibroblast Growth Factor 7; Fibroblast Growth Factors; Growth Substances; Humans; Keratinocytes; Mice; Organ Size; Peroxidase | 1999 |
Studies on purine enzymes in experimental colitis.
Although the role of adenosine deaminase (ADA), adenylate deaminase (AMP-DA), purine nucleoside phosphorylase (PNP) is well documented in gastric and intestinal carcinoma, their role in inflammatory bowel diseases remains unknown. In the present study, we investigated the profile of these enzymes in blood and intestinal tissues during colitis. Colitis induced in Wistar rats by acetic acid was monitored by a marker enzyme myeloperoxidase (MPO). The tissue levels of MPO increased on 1, 2, 5 and 6 days post-administration (PA) of acetic acid and declined to the control levels by day 7 PA. In parallel the blood levels of ADA and AMP-DA decreased on days 1, 2 and 5 without any significant change on days 6 and 7 PA. Similar observations were recorded for these enzymes in the cytosolic extracts of colonic tissue specimens. In contrast, PNP remained unaltered in both blood and tissue samples. These findings suggest an inverse-relationship between inflammation and purine deaminases in both blood and tissues. Topics: Adenosine Deaminase; AMP Deaminase; Animals; Colitis; Male; Peroxidase; Purine-Nucleoside Phosphorylase; Rats; Rats, Wistar | 1999 |
Dietary nucleotides augment dextran sulfate sodium-induced distal colitis in rats.
We have previously shown that enteral and parenteral supplementation of nucleotides (NT) accelerates healing of small-bowel ulcers in rats with indomethacin-induced ileitis. The purpose of this study was to evaluate whether dietary NT supplementation would similarly affect ulcer healing in dextran sulfate sodium (DSS)-induced colitis in rats. Male Sprague-Dawley rats were randomly assigned to receive either nucleotide-free (NF) or NT-supplemented diets. After 2 d of prefeeding, colitis was induced by including 40 g/L of DSS in drinking water for 3 d, followed thereafter by tap water. Rats from each group were killed at 7 and 12 d after induction of colitis. Additional rats were also used for both the groups as controls (untreated groups). The length of colon was measured and evaluated by histological score. Colonic myeloperoxidase (MPO) activity was assessed. In a separate series of experiments, rats were studied at 0, 4, 7, and 12 d for interleukin-1beta (IL-1beta) in rectal dialysate and plasma. Ulceration predominated in the distal colon in DSS-treated rats. There was no significant difference between the histological scores of the NF and NT-supplemented groups either at 7 or 12 d. MPO activity at 7 and 12 d was significantly higher in the NT-supplemented compared to NF group (7 d: 1013 +/- 172 vs. 409.9 +/- 103.2; 12 d: 471.9 +/- 112.4 vs. 223.6 +/- 21.6 units. min-1. g colon-1). IL-1beta concentration in rectal dialysate was significantly higher at 7 d in both groups compared to 0 and 4 d. At 12 d it continued to be significantly elevated in the NT-supplemented group and was greater than in the NT-free group. Our data on the proinflammatory cytokine, in conjunction with MPO activity, strongly suggest that NT supplementation aggravates the severity of DSS-induced colitis in rats. Topics: Animals; Colitis; Dextran Sulfate; Diet; Interleukin-1; Male; Nucleotides; Peroxidase; Rats; Rats, Sprague-Dawley; Weight Gain | 1999 |
Effects of histamine H1 antagonist dithiaden on acetic acid-induced colitis in rats.
To assess the possible involvement of mast cells and/or their mediators in inflammatory bowel diseases, the effect of the histamine H1 antagonist Dithiaden was studied on a model of acetic acid-induced colitis in rats. Dithiaden pretreatment by intracolonic administration was found to reduce the extent of acute inflammatory colonic injury. This was manifested by a decrease in the score of gross mucosal injury, by lowered colonic wet weight and by diminished myeloperoxidase activity reflecting reduced leukocyte infiltration. Vascular permeability and gamma-glutamyl transpeptidase activity, elevated by acetic acid exposure, were decreased after Dithiaden pretreatment. The results indicate that locally administered Dithiaden may protect the colonic mucosa against an acute inflammatory attack by interfering with the action of the major mast cell mediator histamine. Topics: Acetic Acid; Animals; Benzothiepins; Colitis; Colon; gamma-Glutamyltransferase; Histamine; Histamine H1 Antagonists; Intestinal Mucosa; Male; Mast Cells; Organ Size; Peroxidase; Rats; Rats, Wistar | 1999 |
Molecular basis of altered contractility in experimental colitis: expression of L-type calcium channel.
Colitis in experimental animals or idiopathic inflammatory bowel disease, such as ulcerative colitis or Crohn's disease in humans, is associated with reduced muscle contraction. This is predicted to be due to disturbance of Ca2+ homeostasis in the inflamed muscle cell. However, the underlying molecular mechanism remains to be elucidated. Since the catalytic alpha-1 subunit of the L-type Ca2+ channel regulates Ca2+ influx, levels of the alpha-1 mRNA and protein were examined. Colitis induced by intrarectal administration of trinitrobenzenesulfonic acid was monitored by measuring the myeloperoxidase activity and histology. The levels of mRNA and protein were estimated using RT-PCR and immunoblotting. Myeloperoxidase activity increased in the inflamed colon, and the lamina propria and muscle layers showed infiltration of inflammatory cells and loss of crypts. Two alternatively spliced alpha-1 mRNA isoforms were detected in the colonic muscle. The ratio of unspliced to spliced mRNA isoforms remained unaltered in inflamed muscle. In contrast, the level of corresponding protein isozymes decreased in the colitic animals. Thus colitis-induced reduction in the alpha-1 protein may account for the reduced colonic contractility seen in colitis. Topics: Animals; Calcium Channels; Calcium Channels, L-Type; Colitis; Colon; Gastrointestinal Motility; Male; Muscle, Smooth; Peroxidase; Protein Isoforms; Rats; Rats, Sprague-Dawley; RNA, Messenger | 1999 |
Cigarette smoke aggravates experimental colitis in rats.
Tobacco smoking has a complex effect on intestinal inflammation, being protective in ulcerative colitis, whereas it aggravates Crohn's disease. The beneficial effect of smoking has been attributed to nicotine, but the mechanisms underlying the adverse effect are still under investigation. The aim of this study was to examine the effect of cigarette smoking on experimental colitis in rats and to investigate the underlying mechanism.. Rats were exposed daily to cigarette smoke by means of a specialized smoking chamber. Control rats were placed in the same chamber without introducing smoke. In parallel experiments, rats received the ganglionic blocker hexamethonium before smoke exposure. After 2 weeks, colitis was induced by dinitrobenzenesulfonic acid (DNBS), and inflammation was assessed 3 days later.. Exposure to cigarette smoke significantly increased macroscopic and histological damages as well as myeloperoxidase activity compared with sham-treated controls. Treatment with hexamethonium before smoking reversed the effect of the smoke on the colitis, improving all parameters.. Exposure to cigarette smoke aggravates DNBS-induced colitis in the rat. This effect is reversed by hexamethonium, suggesting that a neural pathway is involved. Topics: Animals; Colitis; Colon; Dinitrofluorobenzene; Ganglionic Blockers; Hexamethonium; Male; Nicotine; Peroxidase; Rats; Rats, Sprague-Dawley; Smoking | 1999 |
Neutral endopeptidase (EC 3.4.24.11) terminates colitis by degrading substance P.
Neurogenic inflammation is regulated by sensory nerves and characterized by extravasation of plasma proteins and infiltration of neutrophils from post-capillary venules and arteriolar vasodilatation. Although it is well established that substance P (SP) interacts with the neurokinin 1 receptor (NK1R) to initiate neurogenic inflammation, the mechanisms that terminate inflammation are unknown. We examined whether neutral endopeptidase (NEP), a cell-surface enzyme that degrades SP in the extracellular fluid, terminates neurogenic inflammation in the colon. In NEP knockout mice, the SP concentration in the colon was approximately 2.5-fold higher than in wild-type mice, suggesting increased bioavailability of SP. The extravasation of Evans blue-labeled plasma proteins in the colon of knockout mice under basal conditions was approximately 4-fold higher than in wild-type mice. This elevated plasma leak was attenuated by recombinant NEP or the NK1R antagonist SR140333, and is thus caused by diminished degradation of SP. To determine whether deletion of NEP predisposes mice to uncontrolled inflammation, we compared dinitrobenzene sulfonic acid-induced colitis in wild-type and knockout mice. The severity of colitis, determined by macroscopic and histologic scoring and by myeloperoxidase activity, was markedly worse in knockout than wild-type mice after 3 and 7 days. The exacerbated inflammation in knockout mice was prevented by recombinant NEP and SR140333. Thus, NEP maintains low levels of SP in the extracellular fluid under basal conditions and terminates its proinflammatory effects. Because we have previously shown that intestinal inflammation results in down-regulation of NEP and diminished degradation of SP, our present results suggest that defects in NEP expression contribute to uncontrolled inflammation. Topics: Animals; Blood Proteins; Colitis; Dinitrofluorobenzene; Humans; Mice; Mice, Inbred C57BL; Mice, Knockout; Neprilysin; Neurokinin-1 Receptor Antagonists; Peroxidase; Piperidines; Quinuclidines; Recombinant Proteins; Substance P | 1999 |
Damage to the enteric nervous system in experimental colitis.
Inflammation of the intestine causes pain and altered motility, at least in part through effects on the enteric nervous system. While these changes may be reversed with healing, permanent damage may contribute to inflammatory bowel disease (IBD) and post-enteritis irritable bowel syndrome. Since little information exists, we induced colitis in male Sprague-Dawley rats with dinitrobenzene sulfonic acid and used immunocytochemistry to examine the number and distribution of enteric neurons at times up to 35 days later. Inflammation caused significant neuronal loss in the inflamed region by 24 hours, with only 49% of neurons remaining by days 4 to 6 and thereafter, when inflammation had subsided. Eosinophils were found within the myenteric plexus at only at the earliest time points, despite a general infiltration of neutrophils into the muscle wall. While the number of myenteric ganglia remained constant, there was significant decrease in the number of ganglia in the submucosal plexus. Despite reduced neuronal number and hyperplasia of smooth muscle, the density of axons among the smooth muscle cells remained unchanged during and after inflammation. Intracolonic application of the topical steroid budesonide caused a dose-dependent prevention of neuronal loss, suggesting that evaluation of anti-inflammatory therapy in inflammatory bowel disease should include quantitative assessment of neural components. Topics: Animals; Anti-Inflammatory Agents; Axons; Benzenesulfonates; Budesonide; Cell Count; Colitis; Colon; Dose-Response Relationship, Drug; Enteric Nervous System; Immunohistochemistry; Inflammation; Male; Myenteric Plexus; Neurons; Peroxidase; Rats; Rats, Sprague-Dawley; Submucous Plexus; Thiolester Hydrolases; Time Factors; Ubiquitin Thiolesterase | 1999 |
Beneficial effects of ropivacaine in rat experimental colitis.
Ropivacaine, a new, long-acting local anesthetic agent, has been shown to have beneficial effects in the treatment of ulcerative colitis. Treatment with this drug results in prompt symptomatic relief. The aim of this study was to examine the effects of ropivacaine on mucosal healing and to investigate whether ropivacaine can restore the decreased colonic contractility seen in the diseased state. Colitis was induced in rats by a single intrarectal administration of trinitrobenzene sulfonic acid. Mucosal healing was assessed after 1 week of therapy. The effects on colonic contractility were examined either after 1 week of treatment or by application of the drugs to untreated, inflamed rat colon segments placed in organ baths. After the induction of colitis, daily intracolonic treatment with ropivacaine for 1 week reduced morphological damage and myeloperoxidase activity. One week of treatment also restored the contractile response to acetylcholine. By adding ropivacaine directly to untreated inflamed colonic segments in organ baths, the contractile response to acetylcholine was increased compared with controls. For comparison, the effects of budesonide and 5-aminosalicylic acid were also examined. Ropivacaine improved mucosal healing and restored colonic motor activity in experimental colitis, similar to budesonide but superior to 5-aminosalicylic acid. Topics: Acetylcholine; Amides; Anesthetics, Local; Animals; Budesonide; Colitis; Ethanol; Gastrointestinal Motility; In Vitro Techniques; Male; Mesalamine; Mucous Membrane; Peroxidase; Rats; Rats, Sprague-Dawley; Ropivacaine; Time Factors; Trinitrobenzenesulfonic Acid; Wound Healing | 1999 |
The effect of Oren-gedoku-to on experimental colitis in rats.
In Japan and China, Oren-gedoku-to (a complex mixture of ingredients derived from plants) has been used as a herbal medicine in the treatment of inflammatory and ulcerative diseases. In other countries salicylazosulfapyridine has been used to treat inflammatory bowel disease. In this study, we have compared the effect of Oren-gedoku-to with salicylazosulfapyridine on trinitrobenzene-sulphonic acid-induced colonic damage in rats, a model representative of ulcerative colitis and Crohn's disease in man. Oren-gedoku-to was administered orally for one or two weeks over a range of doses. Tissue damage scores, body weight, spleen weight, colon wet weight and colon wall thickness were measured, and colonic tissue levels of interleukin-8 (IL-8), leukotriene B4 (LTB4), prostaglandin E2 (PGE2), and myeloperoxidase activity were examined. The results indicated that Oren-gedoku-to was effective in the treatment of inflammatory bowel disease in the rat model. Histological observation showed a quicker healing process of the lesions, and a reduction of inflammatory cell infiltration following administration of Oren-gedoku-to. The precise mechanism of action for Oren-gedoku-to is still unclear; however, the reduction of IL-8, LTB4, and PGE2 observed suggests that the mechanism may be different from salicylazosulfapyridine (which has no effect on IL-8). There may be a potential benefit in offering combination therapy for the treatment of inflammatory bowel disease. Topics: Animals; Anti-Ulcer Agents; Body Weight; Colitis; Drugs, Chinese Herbal; Gastrointestinal Agents; Male; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Sulfasalazine; Trinitrobenzenesulfonic Acid | 1999 |
Altered expression of the Na+/H+ exchanger isoform-3 in experimental colitis: effect of garlic.
The sodium-hydrogen exchanger isoform, NHE-3 is essential for the absorption of sodium and water from intestine. Whether this protein plays any role in inflammatory bowel disease is less understood. To address this issue, NHE-3 mRNA and protein levels were estimated in the terminal ileum and colon of the rats having colitis induced with trinitrobenzenesulphonic acid (TNBS). The effect of garlic (Allium sativum) was also evaluated on the expression of NHE-3. The animals were treated with garlic extract intraperitoneally starting 2 h before the TNBS administration until day 4 post-TNBS administration and were sacrificed on day 5. In control animals, the levels of NHE-3 in colon was higher than the ileum. As a result of colitis, the levels of NHE-3 protein and mRNA increased both in the colon and terminal ileum. Garlic treatment of the colitic animals resulted in a selective suppression of NHE-3 in the terminal ileum. Colitis caused an induction of the myeloperoxidase activity, the marker of inflammation in the colon but not in the ileum. These findings suggest that induction of NHE-3 is not primarily due to inflammation. Selective suppression of this protein in ileum by garlic may cause loss of sodium chloride and water during colitis. Topics: Animals; Base Sequence; Blotting, Western; Body Water; Colitis; Colon; DNA Primers; Enzyme Induction; Garlic; Gene Expression; Ileum; Male; Peroxidase; Plants, Medicinal; Rats; Rats, Sprague-Dawley; RNA, Messenger; Sodium; Sodium-Hydrogen Exchanger 3; Sodium-Hydrogen Exchangers; Trinitrobenzenesulfonic Acid | 1999 |
The effect of an inhibitor of matrix metalloproteinases on colonic inflammation in a trinitrobenzenesulphonic acid rat model of inflammatory bowel disease.
Recent publications have reported that matrix metalloproteinases (MMPs) are expressed in colonic tissue taken from ulcerative colitis and Crohn's disease patients.. To evaluate the effects of a matrix metalloproteinase inhibitor, marimastat, on colonic inflammation in experimental colitis induced by trinitrobenzenesulphonic acid (TNBS)-ethanol in the rat.. Rats were dosed (by mouth) for 7 days (b.d.) with either sulphasalazine (50 mg/kg), marimastat (40 mg/kg) or vehicle. TNBS-ethanol was administered rectally on the 4th day of dosing. On the last day of dosing, colons were removed and assessed for inflammation using myeloperoxidase activity, production of soluble TNFalpha (tumour necrosis factor alpha), clinical score and histological assessment. In addition, the bioavailability and effect of marimastat on a range of MMPs were assessed in-vitro.. In this study we have confirmed that marimastat is a broad spectrum MMPI with a bioavailability of 5%. TNBS rats dosed with sulphasalazine had a significantly lower (P < 0.05) myeloperoxidase activity, TNFalpha production and a markedly lower clinical score. Similarly, rats dosed with marimastat had a significantly lower (P < 0.05) myeloperoxidase activity and clinical score, but the TNFalpha production was not significantly reduced.. Dosing rats with TNBS-induced colitis using sulphasalazine or marimastat produced a significant reduction in tissue injury and inflammation. Topics: Animals; Biological Availability; Colitis; Hydroxamic Acids; Inflammatory Bowel Diseases; Male; Matrix Metalloproteinase Inhibitors; Matrix Metalloproteinases; Peroxidase; Protease Inhibitors; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha | 1999 |
Zinc sulphate solution enema decreases inflammation in experimental colitis in rats.
It has been reported that zinc sulphate contributes an anti-inflammatory action in many animal models; however, the impact of zinc in colitis remains unclear. The aim of the present study was to examine the role of zinc sulphate in experimental colitis.. Colitis was induced by 2,4,6-trinitrobenzenesulphonic acid (TNB) in rats. Beginning at the first day of TNB colitis, the rats were treated with a zinc sulphate enema once daily for 6 days. The rats were examined 8 days later.. The TNB induced severe colitis as evidenced by increased mucosal lesion area, mucosal myeloperoxidase (MPO) activity and prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) levels. Six days after the application of the zinc sulphate enema, the mucosal lesion area, MPO activity, PGE2 and LTB4 levels all decreased significantly. Mucosal superoxide dismutase activity remained unchanged after zinc treatments.. Our data suggest that zinc sulphate enemas have an anti-inflammatory action on experimental colitis. Topics: Animals; Colitis; Dinoprostone; Disease Models, Animal; Enema; Female; Intestinal Mucosa; Leukotriene B4; Peroxidase; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; Zinc Sulfate | 1999 |
Aminoguanidine has both an anti-inflammatory effect on experimental colitis and a proliferative effect on colonic mucosal cells.
The aim of this study was to assess the effect of aminoguanidine (AG) on developed colitis and cell proliferation.. Colitis was induced by means of trinitrobenzene sulphonic acid (TNB) in male Wistar rats weighing about 250 g. Seven days after induction of TNB colitis the rats were divided into two groups at random, and one group was orally treated with 1.5 micromol/kg AG each day. We assessed the effect of AG by measuring the mucosal damage, the ulcer area, myeloperoxidase (MPO) activity, inducible nitric oxide synthase (iNOs) activity, and nitrogen oxide in serum 7 days after the beginning of treatment.. AG significantly ameliorated the macroscopic damage score (AG versus control, 5.25 +/- 0.80 versus 7.50 +/- 0.50), the microscopic damage score (5.88 +/- 1.13 versus 9.25 +/- 0.31), ulcer area (0.57 +/- 0.14 versus 1.24 +/- 0.17 cm2), decreased MPO activity (51.5 +/- 9.4 versus 192.2 +/- 60 units/g tissue), and nitrogen oxide in serum (27.2 +/- 1.4 versus 32.3 +/- 1.8 microM) but did not decrease iNOs activity (8732 +/- 435 versus 8672 +/- 357 cpm/g tissue). Moreover, AG accelerated T84 cell proliferation in a dose-dependent manner.. These results suggest that AG ameliorates TNB colitis not only by its anti-inflammatory effect but also by accelerating the proliferation of colonic mucosal cells. AG, accordingly, might well be a useful new medicine to ameliorate inflammatory bowel disease. Topics: Analysis of Variance; Animals; Colitis; Enzyme Inhibitors; Epithelial Cells; Guanidines; Intestinal Mucosa; Male; Nitric Oxide Synthase; Nitrogen Oxides; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 1999 |
Is administration of n-3 fatty acids by mucosal enema protective against trinitrobenzene-induced colitis in rats?
We investigated the protective role of fish oil (FO-source of n-3 FA) enriched diet (in the first protocol) in 20 rats and FO administration intrarectally (in the second protocol) in 40 rats with trinitrobenzene (TNB) colitis. All colonic specimens were pathologically evaluated, myeloperoxidase enzyme activities were measured, leukotriene B4 (LTB4) and LTC4 levels were determined by radioimmunoassay. In the first protocol 10 rats (group A1) were fed with 8% sunflower and cotton oil enriched diet and (group A2) with 8% FO enriched diet for 6 weeks. At the end of this period, TNB (30 mg in 0.25 ml of 30% ethanol) were intrarectally administered. After 2 weeks, rats were sacrificed. MPO activities (2.47 versus 30.17), LTB4 (34.5 versus 903.3) and LTC4 (77.7 versus 456.0) levels were significantly reduced in group A2 compared with group A1 (P<0.005). There was also a significant difference in pathologic scores (1.55 versus 2.12, P<0.002) between two groups. In the first part of the second protocol, 20 male rats were randomized into two equal groups (B1 and B2) and TNB colitis was induced. After 1 day, 1 ml of saline (group B1) or n-3 FA enemas (group B2) were administered every day for 2 weeks. At the end of this period, rats were sacrificed and evaluated as done for previous groups. Although there was no significant difference between the two groups in comparison with MPO enzyme activities and pathologic scores, the LTB4 (130.1 versus 971.0) and LTC4 (126.0 versus 532.0) levels of FO group were significantly reduced (P<0.005). In the second part of the second protocol, 20 male rats were randomized into two groups. One millilitre of saline (group B3) or FO enemas (group B4) were administered to rats every day for 3 days. At the fourth day, TNB-colitis was induced and after 24 h rats were sacrificed. We could not find any significant difference in MPO activities, pathologic scores, LTB4 and LTC4 levels between groups B3 and B4. In conclusion, FO enriched diet decreased both pathologic damage and tissue LT levels. The second protocol of our study revealed that the long-term FO enemas decreased the LTB4 and LTC4 levels; however, did not have any beneficial effect on the tissue lesions. Short periods of FO enemas did not have a protective role in the occurrence of experimental colitis. The present study showed that FO enemas significantly decreased LT levels. The protective effect of FO (oral and enema) in TNB colitis may open a new insight into the treatment of Topics: Animals; Colitis; Colon; Drug Administration Routes; Enema; Fatty Acids, Omega-3; Inflammatory Bowel Diseases; Intestinal Mucosa; Leukotrienes; Male; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenes | 1999 |
Effects of nitric oxide synthase inhibition or sulfasalazine on the spontaneous colitis observed in HLA-B27 transgenic rats.
The objective of this study was to determine the effects that certain nitric oxide synthase inhibitors have on the spontaneous intestinal and colonic inflammation that develops in HLA-B27 transgenic rats and compare these data to those obtained using sulfasalazine (SZ). In an attempt to more closely mimic the clinical situation, drug treatment was begun after the onset of colitis. HLA-B27 male rats that developed clinical signs of colitis (diarrhea/loose stools) at 17 wk of age were randomized into fours groups consisting of one untreated colitic group and three treatment groups that received either aminoguanidine (AG; 52 micromol/kg/day), NG-nitro-L-arginine methyl ester (L-NAME; 45 micromol/kg/day) or SZ (130 mg/kg/day) in their drinking water for 14 days. Aged-matched Fisher 344 male rats were used as healthy controls. After 3 wk of treatment, ileal and colonic mucosal permeabilities, granulocyte infiltration and nitric oxide were quantified using blood-to-lumen clearance of 51Cr-EDTA, tissue myeloperoxidase activity, and plasma levels of nitrate and nitrite, respectively. We found that both AG and L-NAME but not SZ significantly attenuated the increases in plasma nitrate and nitrite levels. Interestingly, all three drugs were effective at significantly attenuating the increases in myeloperoxidase activity in the distal colon. Treatment with AG and SZ but not L-NAME were effective at significantly attenuating the increase in ileal and colonic permeabilities. Quantitative histological analysis revealed that AG and L-NAME but not SZ significantly attenuated the increase in the mucosal thickness and crypt depth in the distal colon compared to untreated colitis. Taken together, these data demonstrate that oral administration of certain nitric oxide synthase inhibitors or SZ to animals with active colitis attenuates the colonic inflammation by at least two different mechanisms. One mechanism appears to be dependent on inhibition of NO production whereas the other mechanism does not. Topics: Animals; Animals, Genetically Modified; Body Weight; Colitis; Colon; Enzyme Inhibitors; HLA-B27 Antigen; Ileum; Male; NG-Nitroarginine Methyl Ester; Nitrates; Nitric Oxide Synthase; Nitrites; Permeability; Peroxidase; Rats; Rats, Inbred F344; Sulfasalazine | 1998 |
Disruption of intestinal barrier function associated with experimental colitis: possible role of mast cells.
The objective was to characterize changes in barrier and transport function in an experimental model of colitis, and to determine whether mast cells contribute to these changes. Colitis was induced in rats with intracolonic 2,4,6-trinitrobenzenesulfonic acid (TNBS, 30 mg) in 50% ethanol. Controls received 0.9% saline or the ethanol vehicle alone. In vivo loop perfusion was used to assess colonic water flux (in microliter.cm-1.h-1) and lumen-to-blood 51Cr-labeled EDTA clearance (% administered dose) after TNBS. Myeloperoxidase (MPO) was used as an index of granulocyte influx. TNBS or its vehicle caused a marked decrease in water absorption and an increase in permeability at 4 h after administration compared with saline. Neither dexamethasone (anti-inflammatory control) nor doxantrazole (mast cell stabilizer) was able to attenuate these early changes likely caused by the vehicle. In contrast, at later times, TNBS (but not its vehicle) also increased 51Cr-EDTA permeability and decreased water absorption; both effects were significantly attenuated by dexamethasone or doxantrazole. These drugs also significantly reduced TNBS-induced MPO accumulation and release of rat mast cell protease II. We conclude that experimental colitis is associated with severe defects in intestinal transport and barrier functions and that mast cells may contribute to the pathogenesis of these changes. Topics: Animals; Biomarkers; Body Water; Chromium Radioisotopes; Chymases; Colitis; Colon; Dexamethasone; Disease Models, Animal; Edetic Acid; Granulocytes; Intestinal Absorption; Male; Mast Cells; Peroxidase; Rats; Rats, Sprague-Dawley; Serine Endopeptidases; Thioxanthenes; Trinitrobenzenesulfonic Acid; Xanthones | 1998 |
Oxazolone-induced colitis in rats: effects of budesonide, cyclosporin A, and 5-aminosalicylic acid.
The intention of the present study was to develop a new hapten-based inflammatory bowel disease model in the rat, useful for pharmacologic screening of new substances with anti-inflammatory properties and immunomodulating capacities. It was considered important to avoid the use of an irritating barrier breaker, such as ethanol.. Dark Agouti rats were skin-sensitized with oxazolone and further challenged intra-rectally with oxazolone dissolved in carmellose sodium (Orabase)/peanut oil. The effects of treatment with budesonide, prednisolone, cyclosporin A, and 5-aminosalicylic acid (5-ASA) were studied.. The intra-rectal challenge with oxazolone in sensitized rats induced an inflammation with an increased colon wet weight, pronounced myeloperoxidase (MPO) activity, and hyperemia/ulcerations in the epithelial lining. Improvement was achieved by treatment with budesonide, prednisolone, and cyclosporin A but not with 5-ASA.. The model fulfills the criteria for a fast, reproducible animal model for human colon inflammation, suitable for pharmacologic screening and studies of an immune-driven colon inflammation. Topics: Animals; Budesonide; Colitis; Colon; Cyclosporine; Disease Models, Animal; Female; Intestinal Mucosa; Mesalamine; Organ Size; Oxazolone; Peroxidase; Rats; Time Factors | 1998 |
Effect of mizolastine on visceral sensory afferent sensitivity and inflammation during experimental colitis.
In the present study the effect of mizolastine (CAS 108612-45-9, SL85.0324-00) a novel potent histamine H1-receptor antagonist, on 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced colitis, a rat model of inflammatory bowel disease, was investigated to determine whether mizolastine has anti-inflammatory properties. Treatment with TNBS resulted in increased nociception in response to rectal balloon distension and caused intestinal damage, tissue oedema and inflammation. Oral mizolastine (0.03-3.00 mg/kg given 1 h before and once daily for 3 days after TNBS treatment) significantly (p < 0.05) reduced nociception (49% at 0.3 mg/kg), gross intestinal damage (78% at 3.0 mg/kg), histological damage (54% at 3.0 mg/kg), intestinal tissue weight (69% at 3.0 mg/kg) and myeloperoxidase activity (66% at 3.0 mg/kg). In contrast, the H1-receptor antagonist terfenadine tested under the same experimental conditions at 3-30 mg/kg was without significant effect. It is concluded that, in addition to its antiallergic properties, mizolastine possesses anti-inflammatory actions that may not be related to its H1-receptor blocking properties, reducing sensory afferent hypersensitivity, damage and neutrophil infiltration observed during colitis. Topics: Animals; Benzimidazoles; Colitis; Colon; Histamine H1 Antagonists; Hypersensitivity; In Vitro Techniques; Male; Neurons, Afferent; Organ Size; Peroxidase; Rats; Rats, Wistar; Terfenadine; Trinitrobenzenesulfonic Acid | 1998 |
Effect of intracolonic benzalkonium chloride on trinitrobenzene sulphonic acid-induced colitis in the rat.
We investigated the effects of benzalkonium chloride (BAC) on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats.. TNBS was administered intrarectally before and/or after BAC treatment. In the first study, the effects of treatment with BAC 6, 12 or 24 h after TNBS were examined. In the second study, animals were treated with BAC before, after or before and after TNBS, and were examined 7 days later. The severity of colitis was assessed by macroscopic and histological scoring of the colonic damage and by determination of colonic myeloperoxidase (MPO) activity. Macrophages and CD4+ and CD8+ T cells were examined by immunohistochemistry.. When BAC was instilled into the colon 6, 12 or 24 h after TNBS, weight loss and macroscopic and histological features of the colon were similar to that of controls (TNBS alone). In contrast, MPO activity was significantly reduced in all three groups post-treated with BAC. In the groups examined 7 days after TNBS treatment, rats post-treated with BAC exhibited increased weight gain and significantly reduced macroscopic damage and MPO activity compared to the TNBS control group. Rats pre-treated with BAC exhibited less macroscopic damage of the colon than rats receiving only TNBS, but histological damage, MPO and weight gain were unchanged from TNBS controls. Immunohistochemistry revealed that BAC pre-treatment increased the numbers of macrophages and T cells in the colon. After TNBS treatment, macrophage accumulation was evident in the colon, but T cells were scarce. However, these cells were preserved or enhanced in the colonic mucosa in TNBS-treated rats that had been pre-treated with BAC.. Treatment with BAC, particularly after induction of colitis, produces a significant reduction in the severity of tissue injury and inflammation through mechanisms that are not fully understood. Topics: Animals; Anti-Infective Agents, Local; Benzalkonium Compounds; CD4 Antigens; CD4-Positive T-Lymphocytes; CD8 Antigens; CD8-Positive T-Lymphocytes; Colitis; Colon; Immunohistochemistry; Intestinal Mucosa; Macrophages; Male; Peroxidase; Rats; Rats, Wistar; Time Factors; Trinitrobenzenesulfonic Acid; Weight Gain; Weight Loss | 1998 |
The effect of heparin on trinitrobenzene sulphonic acid-induced colitis in the rat.
Reduced blood coagulability seems to protect against inflammatory bowel disease; pilot studies using heparin in patients with inflammatory bowel disease have reported positive results.. To evaluate the effects of heparin treatment on microangiographic and on inflammatory parameters in experimental colitis, induced by trinitrobenzene sulphonic acid (TNBS)-ethanol.. Four groups of rats: (i) controls (saline enema), TNBS-induced colitis with (ii) sham treatment (saline, s.c.), (iii) dexamethasone (0.25 mg/kg/day s.c.) and (iv) heparin (500 U/kg t.d.s., s.c.). Microangiography was performed 2 and 4 days after colitis induction. Partial thromboplastin time, colonic wet weight, macroscopic damage score and mucosal myeloperoxidase (MPO) activity were determined at day 4.. TNBS-induced colitis caused a reduction in visible bowel wall vessels, which was prevented by heparin (P < 0.05) but not by steroids. The macroscopic damage scores and colon wet weights were similar in all colitis groups. Compared to untreated colitis the MPO activity in heparin-treated animals was of borderline significance.. Heparin treatment improved microangiographic features and reduced inflammation to a certain degree. Steroids delayed development of colon hypoperfusion, but were ineffective on MPO activity. It remains to be determined if the observed effects are due to the antithrombotic activity of heparin or to an anti-inflammatory action. Topics: Animals; Anti-Inflammatory Agents; Anticoagulants; Blood Platelets; Colitis; Colon; Dexamethasone; Erythrocyte Count; Heparin; Male; Microradiography; Partial Thromboplastin Time; Peroxidase; Rats; Rats, Sprague-Dawley; Treatment Outcome; Trinitrobenzenesulfonic Acid | 1998 |
Colitis-induced changes in the expression of the Na+/H+ exchanger isoform NHE-1.
The sodium hydrogen exchanger (NHE) plays an important role in the absorption of NaCl, the regulation of intracellular pH and cell growth. These functions are compromised in the inflammatory bowel diseases. The objective of this study was to examine the expression of the NHE-1 isoform during colitis induced by acetic acid or trinitrobenzenesulfonic acid in Sprague-Dawley male rats. We also examined the effect of dexamethasone on the expression of NHE-1. Levels of mRNA were estimated using the reverse transcription-polymerase chain reaction and slot blot analysis, and levels of protein were estimated by enhanced chemiluminescence light Western blot analysis. The levels of the NHE-1 mRNA and protein in colonic mucosa increased as assessed at 1, 2, 5 and 7 days post-acetic acid administration and 7 days post-trinitrobenzenesulphonic acid administration in the rats. The levels of mRNA were not suppressed by dexamethasone treatment in either case. These findings demonstrate that colitis-induced expression of the NHE-1 mRNA and protein is independent of the way colitis is induced. Although factor(s) responsible for the induction remain to be identified, our findings showing similar changes in the NHE-2 and NHE-3 mRNA isoforms, together with the lack of their suppression by dexamethasone, suggest that cytokines and intracellular pH are secondary factors. Topics: Animals; Blotting, Western; Colitis; Isoenzymes; Male; Peroxidase; Polymerase Chain Reaction; Rats; Rats, Sprague-Dawley; RNA, Messenger; Sodium-Hydrogen Exchangers | 1998 |
Salicylate hydroxylation as an indicator of hydroxyl radical generation in dextran sulfate-induced colitis.
Reactive oxygen and nitrogen species have been implicated as mediators of mucosal injury in inflammatory bowel disease. This study investigated hydroxyl radical (.OH) generation in the inflamed colon of dextran sulfate sodium (DSS)-induced colitis by measuring the .OH-specific product of salicylate hydroxylation, 2,3-dihydroxybenzoic acid (DHB). Colitis was induced in 6-7 week old CBA/H male mice by supplementing the drinking water with 5% DSS for 7 days. On the last day of dextran exposure, mice were injected with salicylate (SAL) (100 mg/kg i.p.) 60 min before sacrifice, and mucosal homogenates were assayed for SAL and 2,3-DHB by HPLC with fluorescence and electrochemical detection. Mucosal 2,3-DHB levels in mice exposed to 5% DSS were increased by 83% (p < .005); however, SAL levels were also elevated by 182% (p < .001). This translated to a 34% decrease in the ratio 2,3-DHB:SAL in inflamed mucosa, possibly indicating greater catabolism or decreased production of 2,3-DHB. In vitro investigation of the stability of DHBs and SAL in the presence of oxidants of inflammatory lesions revealed that 2,3-DHB and 2,5-DHB were rapidly degraded by hypochlorous acid (HOCl), with initial decomposition rates of 190 and 281 nmol/min, respectively (100microM DHB with 200microM HOCl). Methionine prevented decomposition of DHBs in vitro; however, in mice with 5% DSS-induced colitis, where mucosal myeloperoxidase activity was ten-fold control levels (p < .001), administration of methionine (up to 200 mg/kg i.p.) with SAL was ineffective at increasing the ratio 2,3-DHB:SAL. SAL was also degraded in vitro by HOCl (4.7 nmol/min) resulting in the formation of new fluorescent species which may be useful as indicators of HOCl-mediated injury. Salicylate hydroxylation was unable to provide conclusive evidence supporting a role for .OH in the tissue injury of DSS-induced colitis, as metabolic disturbances in the diseased animals other than changes in .OH generation may have altered 2,3-DHB levels. This problem is relevant to any study involving the in vivo use of trapping molecules. In particular, the susceptibility of 2,3-DHB to degradation by HOCl brings into question the usefulness of salicylate hydroxylation for measurement of .OH-generation in any neutrophilic inflammatory lesion. Topics: Animals; Chromatography, High Pressure Liquid; Colitis; Dextran Sulfate; Hydrogen Peroxide; Hydroxybenzoates; Hydroxyl Radical; Hydroxylation; Hypochlorous Acid; Intestinal Mucosa; Kinetics; Male; Methionine; Mice; Mice, Inbred CBA; Peroxidase; Salicylates; Salicylic Acid | 1998 |
Effects of murine recombinant interleukin-10 on the inflammatory disease of rats transgenic for HLA-B27 and human beta 2-microglobulin.
Rats transgenic for HLA-B27 and human beta 2-microglobulin develop a spontaneous, multisystem, inflammatory disease that resembles human B27-associated disease and that involves the gut mucosa. This model predominantly affects the colon and is characterized by an extensive infiltration of the mucosa by inflammatory cells, largely composed of mononuclear cells. In addition, an increased plasma level of nitric oxide (NO)-derived metabolites was described in this model. Deficiency in the anti-inflammatory cytokine, interleukin-10 (IL-10), leads to the development of colitis in IL-10 knockout mice, suggesting that IL-10 plays a major role in the control of gut inflammation. The objectives of this work were to study the mechanisms of the inflammatory bowel disease (IBD) in HLA-B27 rats and to determine the effects of treatment with IL-10. The 33-3 line of HLA-B27 recombinant rats with established disease was treated in two consecutive experiments with murine recombinant IL-10 for five weeks. Assessment of the effect of this treatment was performed, based on clinical, histological and biological (myeloperoxidase and inducible NO synthase activities; tumor necrosis factor-alpha, interferon-delta, CD3, iNOS and beta-actin mRNA expression. In 33-3 rats with established disease, mesenteric lymph nodes were hyperplastic, and colonic cellularity and MPO and iNOS activities in the colonic mucosa were increased without any detectable effects of IL-10 administration. IFN-gamma and iNOS mRNA were only detected in the colon of transgenic rats. Despite a lack of effect on disease expression, IL-10 strikingly reduced the level of IFN-gamma mRNA in gut mucosa. Up-regulation of IFN-gamma mRNA suggests that the IBD of HLA-B27 rats is mediated by T-helper 1 lymphocytes. Sustained administration of IL-10, in HLA-B27 rats with established disease, efficiently inhibited IFN-gamma mRNA expression but did not influence disease expression: these results indicate that IFN-gamma may exert a critical role at an earlier stage of the disease rather in the maintenance of the lesions. Topics: Animals; Animals, Genetically Modified; beta 2-Microglobulin; Colitis; Female; HLA-B27 Antigen; Humans; Inflammatory Bowel Diseases; Interleukin-10; Lymph Nodes; Mice; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Organ Size; Peroxidase; Phenotype; Rats; Rats, Inbred F344; Recombinant Proteins; RNA, Messenger | 1998 |
Changes in colonic inflammation induced by dextran sulfate sodium (DSS) during short- and long-term administration of rebamipide.
Earlier studies have shown the antiinflammatory effects of histamine and nitric oxide (NO) in a model of colitis induced by DSS. However, the defense system against free radicals in this model remained unclear. The aim of this study was to evaluate the effects of rebamipide, which inhibits the production of free radicals, in this model using male Sprague-Dawley rats. Colitis induced by 1% DSS is characterized by slow, weak inflammation and is regarded as a chronic inflammation model. In contrast, colitis induced by 4% DSS is characterized by fast, strong inflammation and is regarded as the acute inflammation model. Endoscopic examinations, peripheral white blood cell (WBC) counts, and assays of myeloperoxidase activity (MPO) in homogenates of colon mucosa were performed after one week (4% DSS model) and eight weeks (1% DSS model). Inflammation of colon mucosa was milder in the rats given rebamipide compared with controls in both the 4% and 1% DSS model. Furthermore, peripheral WBC counts correlated with colonic MPO activity. These findings indicate that rebamipide works as an antiinflammatory agent in both acute and chronic inflammation. Topics: Acute Disease; Alanine; Animals; Anti-Inflammatory Agents; Anti-Ulcer Agents; Anticoagulants; Chronic Disease; Colitis; Colonoscopy; Dextran Sulfate; Drug Administration Schedule; Leukocyte Count; Male; Peroxidase; Quinolones; Rats; Rats, Sprague-Dawley | 1998 |
Protective role of vagal afferents in experimentally-induced colitis in rats.
The aim of this study was to evaluate the regulatory role of vagal afferents in the development of colonic inflammation induced by trinitrobenzenesulfonic acid (TNBS) in rats. Groups of Wistar rats were treated with capsaicin or its vehicle applied perivagally (sham treatment). Colonic transit time was evaluated, and, two days later, one half of the animals received an intracolonic instillation of TNBS/ethanol (40 mg/kg), and the other received saline. Inflammation was evaluated functionally (gut permeability), biochemically (myeloperoxydase activity) and histologically. Vagal capsaicin deafferentation did not modify colonic transit time. In TNBS treated groups, inflammation was enhanced by capsaicin pretreatment, as determined by an increased gut permeability, MPO activity, and histological damage score. These results suggest that vagal afferents have a protective role in TNBS-induced colitis in rats, unrelated to changes in colonic transit time. Topics: Animals; Autonomic Nervous System; Capsaicin; Colitis; Colon; Denervation; Intestinal Absorption; Intestinal Mucosa; Male; Neurons, Afferent; Neutrophils; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Vagus Nerve | 1998 |
Colitis-induced changes in the level of trace elements in rat colon and other tissues.
Trace elements constitute important prosthetic groups in a number of antioxidant enzymes which neutralize free radicals generated during inflammatory conditions such as colitis. However, the status of trace elements in colitis remains to be found. In the present study the concentrations of zinc, copper, manganese and selenium in the colon, liver and serum of rats with acetic acid (HAc)- or trinitrobenzenesulfonic acid (TNBS)-induced colitis were measured using atomic absorption spectrophotometer. Myeloperoxidase and glutathione peroxidase activities were measured spectrophotometrically. Our results show that the selenium concentration was significantly decreased by 33 and 37.5% in the colon and 69 and 78% in liver by HAc and TNBS treatment, respectively. Similarly the zinc concentration in the colon was decreased by 21 and 28% by HAc- and TNBS-induced colitis as compared to the controls, but manganese and copper, remained unaltered. The serum concentrations of copper, zinc and selenium also remained unaltered during colitis. The weight of HAc-treated rats did not decrease while there was a significant weight loss in the TNBS-treated rats. Myeloperoxidase activity was increased, whereas glutathione peroxidase activity was significantly decreased in the colon inflamed by HAc or TNBS as compared to the controls. These findings suggest that colitis induces a reduction in the tissue levels of trace elements which is independent of the way colitis is induced. Our findings of a reduction in Se and glutathione peroxidase activity together suggest that the reduction in the trace element concentrations is not due to dietary factors or malabsorption. The decrease may severely affect the antioxidant potential of the colon and therefore is a putative factor for the progression of disease. Topics: Acetic Acid; Animals; Colitis; Colon; Copper; Glutathione Peroxidase; Liver; Male; Manganese; Peroxidase; Rats; Rats, Sprague-Dawley; Selenium; Trace Elements; Trinitrobenzenesulfonic Acid; Zinc | 1998 |
Hyperbaric oxygen: a novel modality to ameliorate experimental colitis.
Hyperbaric oxygen (HBO) has been suggested to be beneficial in inflammatory bowel disease but the mechanisms responsible for its therapeutic effects have not been elucidated.. To assess the effect of HBO treatment on colonic damage in two models of experimental colitis, and to examine whether this effect is mediated by modulation of NO synthesis.. Colitis was induced by either flushing the colon with 2 ml 5% acetic acid or intracolonic administration of 30 mg trinitrobenzenesulphonic acid (TNB) dissolved in 0.25 ml 50% ethanol. Rats were exposed to HBO (100% oxygen at 2.4 atmosphere absolute) for one hour twice on the day of colitis induction and once daily thereafter. Control rats were treated only with acetic acid or TNB. Rats were killed 24 hours after acetic acid administration or one and seven days after TNB treatment. The colon was isolated, washed, and weighed, the lesion area was measured, and mucosal scrapings were processed for determination of myeloperoxidase (MPO) and NO synthase (NOS) activities, prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) generation.. In control rats exposed for seven days to HBO, colonic NOS activity was significantly decreased by 61%, compared with its activity in untreated rats (2.93 (0.17) nmol/g/min). HBO significantly reduced by 51 and 62% the extent of injury induced by acetic acid and TNB respectively. The protection provided by HBO was accompanied by a significant decrease in colonic weight, PGE2 generation, MPO, and NOS activities. In acetic acid colitis, LTB4 generation was also significantly decreased.. (1) HBO effectively decreases colitis induced by acetic acid and TNB. (2) The decreased NOS activity induced by HBO suggests that reduction in NO generation may be among the mechanisms responsible for the anti-inflammatory effect of HBO. (3) HBO may be considered in the treatment of patients with refractory inflammatory bowel disease. Topics: Acetic Acid; Animals; Colitis; Hyperbaric Oxygenation; Intestinal Mucosa; Male; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Sprague-Dawley | 1998 |
Protective effect of taurine on TNBS-induced inflammatory bowel disease in rats.
We had previously reported that the protective effect of taurine against indomethacin-induced gastric mucosal injury was due to its antioxidant effects, which inhibited lipid peroxidation and neutrophil activation. In this study, we examined the effect of taurine on reducing the inflammatory parameters of trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease (IBD) in rats. In order to induce IBD, ethanolic TNBS was given to rats intracolonically. Then they received 500 mg/kg/day of taurine orally and were sacrificed one week after IBD induction. While ulceration and inflammation of distal colon with formation of granuloma in the vehicle-treated IBD rats two days after administration of TNBS were observed, treatment with taurine ameliorated colonic damage and decreased the incidence of diarrhea and adhesion. Also, colon weight as an index of tissue edema, which was markedly increased in the IBD rats, became significantly lower after taurine treatment. Myeloperoxidase (MPO) activity in the vehicle-treated IBD rats was substantially increased, compared with that of normal control. The taurine-treated animals significantly reduced MPO activity (35% lower) when compared with that of the vehicle-treated animals. Taurine treatment decreased both basal and formyl-methionyl leucyl phenylalanine-stimulated reactive oxygen generation from colonic tissue in the IBD rats. These results suggest that the administration of taurine reduce the inflammatory parameters in this IBD rat model by increasing defending capacity against oxidative damage. Topics: Animals; Colitis; Colon; Dinoprostone; Eicosanoids; Inflammatory Bowel Diseases; Luminescent Measurements; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Taurine; Trinitrobenzenesulfonic Acid | 1998 |
Effect of chronic nicotine administration on trinitrobenzene sulphonic acid-induced colitis.
Smoking, probably due to nicotine, has a bivalent effect on inflammatory bowel disease, ameliorating disease activity in ulcerative colitis and with a deleterious effect on Crohn's disease. The effect of nicotine patches in ulcerative colitis is controversial.. To investigate the effect of chronic nicotine use in a rat model of colitis.. Colitis was induced in Sprague-Dawley rats by rectal administration of 30 mg trinitrobenzene sulphonic acid (TNBS) in 50% ethanol. Nicotine was dissolved in drinking water (2.5, 12.5, 25 and 250 microg/ml), with rats drinking ad libitum. Nicotine administration started 10 days prior to damage induction and had no effect on weight gain or daily food intake of rats. Rats were sacrificed 1 and 5 days after TNBS administration, their colons resected, rinsed, weighed, damage assessed macroscopically (mm2) and microscopically and tissue processed for myeloperoxidase (MPO) and nitric oxide synthase (NOS) activities, leukotriene B4 (LTB4), prostaglandin E2 (PGE2) generation and interleukin-1 (IL-1) serum levels.. Nicotine, by itself, caused no damage to the colon. Nicotine had a dose-dependent bivalent effect on colitis, significantly reducing macroscopic damage from 983 +/- 10 mm2 on TNBS alone to 429 +/- 118 mm2 on TNBS plus 12.5 microg/ml of nicotine, and escalating to 1086 +/- 262 mm2 on 250 microg/ml of nicotine. Segmental weight declined significantly (from 2.4 +/- 0.2 to 1.65 +/- 0.20 g/10 cm), on 12.5 microg/ml nicotine, as did MPO activity (from 3.2 +/- 0.4 to 0.7 +/- 0.1 units/g). All these parameters returned to the levels of TNBS alone when the dose of nicotine was increased to 250 microg/ml. Nicotine had no effect on NOS activity, PGE2 generation and serum IL-1 levels, but increased LTB4 generation.. Nicotine has a dose-dependent bivalent effect on TNBS-induced colitis which is not due to reduction in IL-1 serum levels or PGE2 generation, and is not NOS-mediated. Topics: Animals; Colitis; Colon; Dinoprostone; Dose-Response Relationship, Drug; Interleukin-1; Intestinal Mucosa; Leukotriene B4; Male; Nicotine; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1998 |
Incrimination of anaerobic bacteria in the induction of experimental colitis.
Commensal bacteria may participate in the pathogenesis of bowel inflammation. We studied the role of bacteria from the rat colonic flora on transmural inflammation induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS). First, bacterial translocation to the colonic wall after induction of colitis was assessed by microbiological and histological methods. Second, rats with a colonic segment excluded from fecal transit were prepared for recolonization with preselected bacteria and used to test the effects of different species on inflammation (eicosanoid release, tissue myeloperoxidase) and damage (histology). Six strains (three aerobes and three anaerobes) were identified in colonic tissue 24 h after induction of colitis. Acridine staining showed bacteria in necrotic areas of the mucosa and invading the submucosa. Rats with excluded colon and sterile culture of luminal washings showed mild inflammation and low mucosal damage in response to TNBS. Rats colonized with anaerobes showed significantly higher eicosanoid release than rats colonized with aerobes only. Moreover, submucosal-lesions were mostly observed in rats with anaerobes. Our findings suggest that colonic anaerobes play a key role in transmural inflammation. Topics: Animals; Bacteria, Anaerobic; Bacterial Infections; Colitis; Colon; Dinoprostone; Ethanol; Male; Necrosis; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1997 |
Stress-induced enhancement of colitis in rats: CRF and arginine vasopressin are not involved.
Because exacerbation of colitis seems to be associated with stress, we proposed evaluating the influence of stress and the involvement of corticotropin-releasing factor (CRF) and arginine vasopressin (AVP) on experimental colitis in rats. Partial restraint stress was applied during 4 consecutive days, before or after intracolonic 2,4,6-trinitrobenzenesulfonic acid (TNB) instillation (15 mg) in rats. Finally, two groups of rats were centrally injected with alpha-helical CRF-(9-41) (5 micrograms) or AVP antagonist (5 micrograms) before each session of stress. Stress was applied before or right after TNB enhanced colitis, with an increase in macroscopic and histological scores and myeloperoxidase activity, alpha-Helical CRF-(9-41) or AVP antagonist had no effect on TNB-induced colitis but enhanced the effects of stress on colitis. These results show that stress may exacerbate experimental colitis in rats and that CRF and AVP are not responsible for this effect. Topics: Animals; Arginine Vasopressin; Colitis; Colon; Corticotropin-Releasing Hormone; Hormone Antagonists; Injections, Intraventricular; Intestinal Mucosa; Male; Peptide Fragments; Peroxidase; Rats; Rats, Wistar; Restraint, Physical; Stress, Physiological; Trinitrobenzenesulfonic Acid | 1997 |
Inducible nitric oxide synthase plays a critical role in resolving intestinal inflammation.
Overproduction of nitric oxide by inducible nitric oxide synthase (iNOS) has been proposed as a pathogenic factor in colitis. The objective of this study was to examine the role of iNOS using iNOS-deficient mice in experimental colitis.. Colitis was induced by intrarectal instillation of 3% acetic acid and assessed for neutrophilic infiltration and intestinal injury over 7 days. iNOS messenger RNA expression was also measured.. At 24 hours, acetic acid induced a mild colitis in wild-type mice. An increase in neutrophil infiltration and tissue edema was also observed. In the iNOS-deficient mice, a twofold increase in macroscopic damage was observed. Neutrophil infiltration and tissue edema were similar to those in wild-type animals at this time point. Although inflammation in wild-type mice had resolved by 7 days, a sevenfold increase in damage score and elevated myeloperoxidase level were still evident in iNOS-deficient mice. A striking increase in the message for iNOS was observed in inflamed wild-type mice at 24 hours and was still present at 72 hours. No message was found in iNOS-deficient mice.. Induction of iNOS seems to be a critical protective response to injury in intestinal inflammation possibly by reducing leukocytic infiltration. Topics: Animals; Colitis; Enzyme Induction; Female; Male; Mice; Mice, Inbred C57BL; Nitric Oxide Synthase; Peroxidase; RNA, Messenger | 1997 |
Anti-inflammatory properties of interleukin-10 administration in hapten-induced colitis.
Therapeutic efficacy of interleukin-10 administration in colonic inflammation was assessed in rats. Following intracolonic instillation of 2,4,6-trinitrobenzene sulfonic acid (TNBS), subcutaneous administration of 1-1000 micrograms/kg per day interleukin-10, or a placebo (0.9% NaCl) was commenced and continued for 5 days. Interleukin-10 administered at 1, 10 and 100 micrograms/kg per day significantly reduced myeloperoxidase activity by 34, 57, and 28%, respectively, compared to the placebo-treated group, which was paralleled by an attenuation of colonic tumor necrosis factor alpha (TNF-alpha) content. In contrast, the severity of mucosal necrosis was not affected by interleukin-10 administration at the dose range used. In addition, the 10-fold elevation in nitric oxide release, 5-fold rise in colonic nitrite production and enhanced expression of inducible nitric oxide synthase, associated with TNBS colitis, was not suppressed by interleukin-10. Interleukin-10 gene expression was elevated during the first 14 days of TNBS colitis. We conclude that 5 days administration of interleukin-10 in TNBS colitis displays mild anti-inflammatory properties which were not mediated via a nitric oxide-dependent pathway, but may involve TNF-alpha. Topics: Animals; Anti-Inflammatory Agents; Colitis; Female; Gene Expression; Interleukin-10; Leukocyte Count; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha; Up-Regulation | 1997 |
Evaluation of the role of neutrophils in the pathogenesis of acetic acid-induced colitis in mice.
Neutrophils are thought to play a role in the pathogenesis of inflammatory bowel diseases (IBD) such as ulcerative colitis and Crohn's disease, since prominent neutrophil infiltration has been observed in the inflamed colonic mucosa of patients with IBD. However, the role of neutrophils in the pathogenesis of IBD and experimental colitis remains equivocal. The aim of the present study is to clarify the possible role of neutrophils in the progression of acetic acid-induced colitis in mice.. Using neutropenic mice treated with cyclophosphamide or with an LTB4 receptor antagonist, ONO-4057, the relationship between the severity of macroscopic colonic damage, the extent of myeloperoxidase (MPO) activities in the colonic tissues, and the number of neutrophils in the blood were examined after induction of colitis in mice.. Changes of MPO activity in the colonic tissues paralleled well with the severity of the mucosal damage. In spite of a significant reduction in the number of neutrophils in the blood in cyclophosphamide-treated mice, neither the severity of mucosal damage in the colon nor the increase in MPO activities in the colonic tissues was affected 24 h after induction of colitis. Treatment with ONO-4057 significantly suppressed both the severity of mucosal damage in the colon and MPO activities in the colonic tissues in acetic acid-induced colitis in mice.. The present results, obtained using treatment with cyclophosphamide and ONO-4057, show that the severity or the progression of acetic acid-induced colitis in mice was not influenced by a reduction of circulating neutrophils to about 25% of base line. Topics: Acetic Acid; Animals; Colitis; Colon; Cyclophosphamide; Immunosuppressive Agents; Intestinal Mucosa; Male; Mice; Mice, Inbred C57BL; Neutropenia; Neutrophils; Peroxidase; Phenylpropionates | 1997 |
The efficacy of BAY y 1015 in dextran sulfate model of mouse colitis.
There is crucial evidence that leukotrienes are significant mediators of inflammation in inflammatory bowel diseases (IBD). Thus, selective inhibition of leukotriene synthesis is believed to provide a novel approach to therapy of IBD. The aim of the study is to study the efficacy of a potent 5-lipoxygenase activating protein inhibitor (FLAP), BAY y 1015 in a dextran sulfate model of mouse colitis.. Outbred female mice weighing approximately 25 grams were used to produce acute or chronic colitis by feeding 5% dextran sulfate in drinking water.. Colitic mice were treated with placebo (3% starch suspension, 0.1 ml. p.o., bid) or BAY y 1015 at 8 or 24 mg/kg, p.o., bid or olsalazine, 150 mg/kg/day, p.o.. Efficacy was determined by measuring daily disease activity index (DAI), quantitative histological scores, qualitative histology and measurement of tissue myeloperoxidase (MPO) and leukotriene B4 (LTB4) levels.. BAY y 1015 was significantly more effective in improving the qualitative histology, inhibiting the DAI, inflammation scores (37-79%), crypt scores (28-71%), MPO (49-57%) and LTB4 levels (56-63%) compared to placebo treatment at all levels of colitis. The two doses of BAY y 1015 were equipotent in decreasing TLB4 levels. BAY y 1015 was significantly better than olsalazine in two of the three protocols used in this study. In the advanced disease level both doses of BAY y 1015 were equipotent in inhibiting crypt and (28-32%) inflammation scores (34-36%), LTB4 (34-56%) and MPO 41-49%) compared to olsalazine.. This study suggests the possibility of investigating the use of this compound for the treatment of human inflammatory bowel diseases. Topics: Animals; Colitis; Dextran Sulfate; Disease Models, Animal; Female; Leukotriene B4; Lipoxygenase Inhibitors; Mice; Peroxidase; Quinolines | 1997 |
Intestinal inflammation and barrier function in HLA-B27/beta 2-microglobulin transgenic rats.
Since intestinal inflammation is correlated with impaired barrier functions, transgenic HLA-B27/human beta 2-microglobulin rats that spontaneously develop intestinal inflammation were used to investigate whether onset of inflammation or impaired barrier function was the initial event.. During the age period of 9-14 weeks, transgenic and non-transgenic (control) rats were gavaged weekly with the marker molecules, 51Cr-ethylenediaminetetraacetic acid, 1-deamino-8-D-arginine vasopressin, and albumin, which were quantified in blood or urine.. At 12 weeks of age the first signs of inflammation appeared with decreased body weight gain, decreased urine production, and onset of diarrhea. By 14-15 weeks of age all transgenic rats had developed intestinal inflammation, as confirmed by histology and increased myeloperoxidase content, whereas no inflammation was observed in controls. Intestinal passage of the markers did, however, not differ between transgenic and control rats over the studied period.. The results suggest that intestinal inflammation precedes altered intestinal barrier function in this inflammation model. Topics: Animals; Animals, Genetically Modified; beta 2-Microglobulin; Colitis; HLA-B27 Antigen; Humans; Inflammatory Bowel Diseases; Intestinal Absorption; Intestinal Mucosa; Male; Peroxidase; Rats; Rats, Inbred F344; Tumor Necrosis Factor-alpha | 1997 |
Expression and secretion of lipocortin 1 in gut inflammation are not regulated by pituitary-adrenal axis.
Lipocortin 1 is considered a mediator of the anti-inflammatory actions of glucocorticoids. We have shown that this protein is overexpressed and secreted during an experimental colitis induced by intraluminal injection of trinitrobenzenesulfonic acid (TNBS) in rats. We studied here the in vivo regulation of lipocortin 1 expression and secretion in this model, either by glucocorticoids using adrenalectomized or dexamethasone-treated (3 mg/24 h) animals or by pituitary factors using hypophysectomized animals. Inflammation was evaluated by measuring myeloperoxidase activity and by histological scoring of the damage. Lipocortin 1 was detected by immunoblotting, and its secretion was studied by incubating colonic specimens in-culture medium. In the colon of TNBS-injected animals, cumulative histological damage scores were increased in adrenalectomized and decreased in dexamethasone-treated animals compared with control and hypophysectomized animals. The colons of all TNBS-injected animals (controls, adrenalectomized, dexamethasone treated, hypophysectomized) overexpressed and secreted lipocortin 1. In conclusion, the induction of lipocortin 1 overexpression and secretion during this colitis occurs independently of glucocorticoids or pituitary factors. Topics: Animals; Annexin A1; Anti-Inflammatory Agents; Colitis; Colon; Corticosterone; Male; Osmolar Concentration; Peroxidase; Pituitary-Adrenal System; Rats; Rats, Wistar; Reference Values | 1997 |
Rutoside as mucosal protective in acetic acid-induced rat colitis.
The effect of the flavonoid rutoside on acetic acid-induced rat colitis was studied. Rats were pretreated orally with different doses of the flavonoid (10, 25, and 100 mg/kg) 48, 24, and 1 hour prior to colitis induction and examined for colonic damage 24 hours later. Colonic inflammation was characterized by gross and microscopical injury, bowel wall thickening, abolition of fluid absorption, glutathione depletion, enhanced leukotriene B4 synthesis, and increased levels of myeloperoxidase and alkaline phosphatase activities. Rutoside treatment (25 and 100 mg/kg) reduced histologic injury and prevented the increase in alkaline phosphatase activity, but it had no effect on myeloperoxidase levels or leukotriene B4 synthesis. In addition, glutathione depletion was effectively counteracted at the dose of 25 mg/kg, whereas fluid absorption was achieved at the highest dose assayed. It is concluded that rutoside has an acute anti-inflammatory activity in this model which may be related to a putative direct protective effect on intestinal cells, mainly enterocytes, in which the antioxidative properties of the flavonoid may play a role. Topics: Acetic Acid; Administration, Oral; Animals; Colitis; Colon; Intestinal Absorption; Intestinal Mucosa; Peroxidase; Rats; Rats, Wistar; Rutin | 1997 |
Antiinflammatory effects of human milk on chemically induced colitis in rats.
We examined the effects of a human milk diet on rats with chemical colitis induced with a 4% acetic acid enema. Colonic myeloperoxidase activity was used as a surrogate marker for neutrophil infiltration. Control rats fed rat chow had little colonic myeloperoxidase activity; geometric mean, 0.27 U/g of tissue. Rats with colitis fed rat chow had significantly increased colonic myeloperoxidase activity (geometric mean, 6.76 U/g, p < 0.01 versus no colitis), as did rats with colitis fed infant formula or Pedialyte (geometric mean, 6.92 and 8.13 U/g, respectively, both p < 0.01 versus no colitis). Animals with colitis fed human milk had significantly lower colonic myeloperoxidase activity (geometric mean, 2.34 U/g) than did animals with colitis fed either chow or infant formula (p < 0.001). Similar effects were seen in rats with colitis fed infant formula supplemented with recombinant human IL-1 receptor antagonist (geometric mean, 1.95 U/g). These data show that orally administered human milk has an antiinflammatory effect on chemically induced colitis in rats, which may be mediated in part by IL-1 receptor antagonist contained in human milk. Topics: Acetic Acid; Acute Disease; Animals; Anti-Inflammatory Agents; Colitis; Enteral Nutrition; Female; Humans; Leukocytes; Male; Milk, Human; Peroxidase; Pilot Projects; Rats; Rats, Sprague-Dawley | 1997 |
Time-dependent actions of nitric oxide synthase inhibition on colonic inflammation induced by trinitrobenzene sulphonic acid in rats.
The time-dependent actions following pretreatment or delayed administration of the nitric oxide (NO) synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME) on colonic inflammation and inducible NO synthase activity following the intrarectal administration of trinitrobenzene sulphonic acid (TNBS) were evaluated in the rat. Intracolonic instillation of TNBS (30 mg in 0.25 ml of 50% ethanol) led to macroscopic injury, an increase of mucosal myeloperoxidase activity and the expression of the Ca2+-independent inducible NO synthase over 8 days. The inflammatory response following TNBS reached maximum levels between 12 and 72 h and then it declined until 14 days. Oral administration of L-NAME (25 mg/kg per 24 h in the drinking water) 2 days before TNBS augmented macroscopic damage and increased colonic inducible NO synthase activity 6, 12, 24 and 72 h after TNBS administration. In contrast, when L-NAME was administered 6 h after TNBS instillation, at time of expression of inducible NO synthase, the macroscopic lesions were reduced, as well as the enhanced inducible NO synthase activity, determined, over 72 h. Delayed (6 h after TNBS) administration of L-NAME also attenuated the colonic myeloperoxidase activity provoked by TNBS, after 24 h. This activity was not affected by pretreatment (2 days before TNBS) with L-NAME. These findings indicate that the timing of administration of non-selective NO synthase inhibitors such as L-NAME, in models of colitis is critical to the eventual outcome. Thus, pretreatment with L-NAME, which will inhibit constitutive NO synthase, exacerbates the subsequent damage following challenge. In contrast, delayed administration of L-NAME at the time of inducible NO synthase expression, has a beneficial action on the colonic injury and inflammation. Topics: Animals; Colitis; Enzyme Inhibitors; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Wistar; Time Factors; Trinitrobenzenesulfonic Acid | 1997 |
Intracolonic release of nitric oxide during trinitrobenzene sulfonic acid rat colitis.
Nitric oxide is thought to play an important role in modulating the inflammatory process. Recently an increase in the inducible form of nitric oxide synthase (iNOS) has been found in the rat trinitrobenzene sulfonic acid model of experimental colitis, and inhibition of nitric oxide synthase activity resulted in an amelioration of tissue injury. The aim of our study was to evaluate in vivo intracolonic release of nitric oxide in this model of colitis. Experimental colitis was induced in male Sprague-Dawley rats by a single intracolonic administration of trinitrobenzene sulfonic acid. Nitrite levels were determined in rectal dialysates by HPLC. The tissue myeloperoxidase and iNOS and the luminal leukotriene B4 were also measured. Nitrite levels were significantly increased in rectal dialysates during colitis and correlated significantly with tissue myeloperoxidase and iNOS activity. The correlation between nitrite dialysate levels and wall iNOS activity confirms that nitrite in dialysates is produced by inflammatory cells and not by colonic bacterial flora. Determination of nitrite levels in rectal dialysates seems a valuable method to monitor colonic inflammation in rat trinitrobenzene sulfonic acid colitis. Topics: Animals; Colitis; Colon; Disease Models, Animal; Leukotriene B4; Male; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Nitrites; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1997 |
Beneficial effect of ursodeoxycholic acid on mucosal damage in trinitrobenzene sulphonic acid-induced colitis.
Recently we observed that ursodeoxycholic acid (UDCA) ameliorates an experimental small intestinal inflammation induced by indomethacin in the rat. In this study, we have tested whether ursodeoxycholic acid also reduces mucosal damage in the bile-independent trinitrobenzene sulphonic acid (TNB) model of experimental colitis.. Intestinal inflammation (colitis) was induced in male Sprague-Dawley rats (250-300 g) by intracolonic administration of TNB (30 mg in 50% ethanol). Rats were treated with UDCA (10 mg/kg) either for 3 days starting with the administration of TNB for an acute inflammation (n = 11) or for 8 days starting one day after induction of colitis related to a more acute/chronic inflammation (n = 11). Rats were sacrificed at day 3 or day 9, respectively. Healing of induced colitis was assessed by macroscopic and blinded microscopic analysis as well as by measurement of bowel wet weight, daily body weight, and myeloperoxidase activity. All examinations were separately performed in three colon segments (S1 3-5 cm, S2 5.5-8 cm and S3 8.5-11 cm from anus).. UDCA treatment significantly reduced macroscopically and microscopically detectable injury in acute inflammation in segments 1 and 2. The colitis-rats with acute/chronic inflammation had less marked mucosal damage. Nevertheless, UDCA treatment led to a significant decrease of visible injury parameters which was seen exclusively at the area of maximal ulceration (S2). Furthermore, a significant increase in body weight of UDCA-treated TNB rats compared to controls from day 5 on was found.. Ursodeoxycholic acid attenuates the severity of acute inflammation and inhibits the development of acute/chronic inflammation predominantly around the area of maximal ulceration in TNB-induced colitis. In addition to our previous studies and results in indomethacin induced enteritis, these data may provide a rationale for studying how UDCA modulates functions of immune cells in the colonic mucosa. Topics: Animals; Body Weight; Colitis; Intestinal Mucosa; Male; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Time Factors; Trinitrobenzenesulfonic Acid; Ursodeoxycholic Acid | 1997 |
Selective depletion of neutrophils by a monoclonal antibody, RP-3, suppresses dextran sulphate sodium-induced colitis in rats.
Administration of dextran sulphate sodium to animals induces acute colitis characterized by infiltration of large numbers of neutrophils into the colonic mucosa, which histologically resembles human active ulcerative colitis. It has been reported that neutrophils and the reactive oxygen metabolites produced by them are involved in the progress of ulcerative colitis. This study was intended to clarify their roles by using this animal model. First, possible sources and species of reactive oxygen metabolites were determined using luminol-dependent chemiluminescence with addition of enzyme inhibitors and reactive oxygen metabolite scavengers. Next, to examine whether neutrophils and hypochlorous acid derived from them contribute to tissue injury, we administered RP-3, a monoclonal antibody capable of selectively depleting neutrophils, and taurine, a hypochlorous acid scavenger, to rats treated with dextran sulphate sodium. Addition of azide, taurine, catalase, superoxide dismutase and dimethyl sulphoxide into colonic mucosal scrapings significantly inhibited chemiluminescence production, but allopurinol and indomethacin had no effects. These results suggest that excessive hypochlorous acid, hydrogen peroxide, superoxide anion and hydroxyl radical are generated by the inflamed colonic mucosa. Intraperitoneal injections of RP-3 significantly suppressed bleeding, tissue myeloperoxidase activity, chemiluminescence production and erosion formation. On the other hand, administration of taurine tended to inhibit bleeding and erosion formation to some extent, although it could not significantly suppress them. These data suggest that neutrophils play an important role in the development of this colitis and that hypochlorous acid might be one of the causes of tissue injury induced by neutrophils. Topics: Animals; Antibodies, Monoclonal; Blood Cell Count; Colitis; Dextran Sulfate; Eosinophils; Indicators and Reagents; Leukocyte Count; Luminescent Measurements; Luminol; Male; Neutrophils; Peroxidase; Rats; Rats, Wistar; Taurine | 1997 |
Anti-P-selectin antibody exacerbated inflammatory responses in acetic acid-induced colitis.
Topics: Acetic Acid; Animals; Antibodies; Colitis; Colon; Immunoglobulin G; Inflammation; Male; Nitric Oxide Synthase; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Superoxides | 1997 |
The 21-aminosteroid tirilazad mesylate can ameliorate inflammatory bowel disease in rats.
The 21-aminosteroid tirilazad mesylate (U74006F) is a lipophilic antioxidant and free radical scavenger that has been reported to attenuate brain or spinal cord injury caused by trauma, stroke, ischemia and reperfusion injury. In this study, we have examined the effect of U74006F in reducing the inflammatory parameters of trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease (IBD) in rats. To induce IBD, rats were given ethanolic TNBS intracolonically. Rats received either 1) TNBS and U74006F 2) TNBS and vehicle or 3) saline and vehicle. Rats were sacrificed 1, 2 and 3 weeks after IBD induction. Colon to body weight ratio (an index of tissue edema) was markedly increased in the vehicle-treated IBD rats after 1 week of administration of TNBS. The ratio was significantly lower after U74006F treatment and the trend remained even after 3 weeks of chronic inflammation. Myeloperoxidase (MPO) activity in vehicle-treated IBD rats was substantially increased compared with controls during the entire 3 weeks of the experiment. U74006F-treated animals had significantly reduced MPO activity (60% lower) when compared with vehicle-treated animals at the end of the second and third weeks. These observations were confirmed by histopathology studies showing reduced granulocyte infiltration after drug treatment. U74006F treatment decreased basal (by 70%) and fMLP stimulated (by 75%) superoxide generation from colonic tissue from IBD rats compared with vehicle treatment after 2 weeks, but there was no apparent difference in superoxide generation among all three groups after 3 weeks. The results of this study suggested that administration of U74006F effectively reduces the inflammatory parameters in this chronic rat model of IBD. As such, U74006F may be therapeutically beneficial for the treatment of IBD in humans. Topics: Animals; Antioxidants; Body Weight; Colitis; Colon; Free Radical Scavengers; Inflammatory Bowel Diseases; Lipid Peroxides; Luminescent Measurements; Male; Organ Size; Peroxidase; Pregnatrienes; Rats; Rats, Sprague-Dawley; Superoxides; Trinitrobenzenesulfonic Acid | 1996 |
Increased permeability occurs in rat ileum following induction of pan-colitis.
Acetic acid-induced pan colitis in rats leads not only to colonic injury but also to a bystander ileal injury, characterized by decreased fluid and electrolyte absorption without associated histological injury or infiltration of inflammatory cells. To examine the nature of this decreased ileal fluid and electrolyte absorption, we measured effect of acetic acid-induced pancolitis on ileal transmural sodium and chloride transport, as well as on ileal permeability to mannitol and inulin on mucosal sheets mounted in Ussing chambers. In addition, ileal tight junctional morphology was assessed by electron microscopy. In colitic animals, ileal serosal-to-mucosal sodium and chloride transmural fluxes were increased (P<0.05); compatible with the observed decrease in net fluid absorption. Mannitol and inulin ileal serosal-to-mucosal and mucosal-to-serosal ileal fluxes were similarly increased (P<0.05), suggesting that an increase in ileal permeability occurred during acetic acid-induced pancolitis. This increase in ileal permeability was not accompanied by changes in tight junctional ultrastructure. These results suggest that: (1) the decrease in ileal fluid and electrolyte absorption seen during acetic acid-induced rat pancolitis occurred in parallel with a rise in both transcellular and paracellular permeability, and (2) the ileal permeability changes were not accompanied by structural changes. Topics: Animals; Cell Membrane Permeability; Colitis; Disease Models, Animal; Electrophysiology; Ileum; Intestinal Absorption; Male; Microscopy, Electron; Peroxidase; Rats; Rats, Sprague-Dawley | 1996 |
Keratinocyte growth factor ameliorates mucosal injury in an experimental model of colitis in rats.
Keratinocyte growth factor (KGF) is known to enhance tissue repair in the skin; however, its role in the gastrointestinal tract is largely unknown. The aim of this study was to evaluate the effects of exogenous KGF in an experimental model of colitis in rats.. KGF was administered before or after induction of colitis with 2,4,6-trinitrobenzenesulfonic acid/ethanol. In the first two study groups, KGF (5 mg/kg) was administered intraperitoneally 24 hours and 1 hour before induction of colitis; animals were killed 8 hours (n=10) and 1 week (n=10) after injury. In subsequent study groups, KGF or vehicle treatment was begun 24 hours after the induction of colitis at doses of 5 (n=20), 1 (n=10), and 0.1 (n=10) mg/kg intraperitoneally and continued once daily for 1 week. Colonic tissue samples were evaluated macroscopically and microscopically for mucosal injury and assayed for myeloperoxidase activity.. Administration of KGF after but not before induction of colitis significantly ameliorated tissue damage. Macroscopic necrosis and microscopic ulcerations were reduced by 40%-50% at KGF doses of 1 and 5 mg/kg.. Exogenous KGF has a key role in mucosal healing in an experimental model of colitis in rats. Topics: Animals; Cell Division; Colitis; Disease Models, Animal; Fibroblast Growth Factor 10; Fibroblast Growth Factor 7; Fibroblast Growth Factors; Growth Substances; Intestinal Mucosa; Male; Mucins; Mucus; Necrosis; Peroxidase; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Ulcer | 1996 |
Toxic dilatation of colon in a rat model of colitis is linked to an inducible form of nitric oxide synthase.
The contribution of nitric oxide (NO) to the altered colonic contractility of acute colitis was investigated in the 2,4,6-trinitroben-zenesulfonic acid model. NO synthase was measured in colonic tissue; the effects of NO synthase inhibition on colonic contractility were studied in vitro and in vivo. Inducible NO synthase was not detected in normal colons, whereas inflamed colons showed high activity. Acute inflammation was associated with enlarged colonic perimeter. NO synthase inhibitors or selective inhibitors of the inducible enzyme prevented colonic dilatation. In vitro, contractile responses to KCl were lower in muscle from colitic than control rats. After NO synthase inhibition, however, no difference was observed between colitic and control muscle contractility. In vivo, intracolonic pressure was lower in colitic than in control rats. Selective inhibition of inducible NO synthase increased intracolonic pressure in colitic but not in control rats. In conclusion, NO generation by inducible enzymes impairs smooth muscle contractility in colitis and may be involved in the pathogenesis of toxic dilatation of the colon. Topics: Animals; Arginine; Colitis; Colon; Dexamethasone; Dilatation; Disease Models, Animal; Enzyme Induction; Enzyme Inhibitors; Guanidines; Hypoxanthines; Inflammation; Male; Muscle Contraction; Muscle, Smooth; NG-Nitroarginine Methyl Ester; Nifedipine; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1996 |
Action of sensory neurons in an experimental at colitis model of injury and repair.
The influence of sensory nerves on inflammation and healing was studied in a rat colitis model at different stages of inflammation. Studies were performed in animals with and without ablation of sensory nerves, which was achieved by pretreatment with the neurotoxin capsaicin. Colitis was induced by a rectal enema containing trinitrobenzenesulfonic acid (50 mg/kg) in 50% ethanol. Severity of inflammation was markedly increased 3 and 7 days after induction of colitis in the capsaicin-pretreated group compared with the vehicle group as determined by a macroscopic damage score (at 3 days, 12.0 +/- 0.7 vs. 7.5 +/- 1.5; at 7 days, 12.2 +/- 0.8 vs. 6.5 +/- 0.8; P < 0.05), by histology (ulceration score at 3 days, 82 +/- 12 vs. 40 +/- 11%; at 7 days, 92 +/- 5 vs. 46 +/- 13%; P < 0.05), and by myeloperoxidase activity (at 3 days, 133 +/- 30 vs. 42 +/- 14 U/mg protein; at 7 days, 76 +/- 11 vs. 39 +/- 11 U/mg protein; P < 0.05). There was no significant difference in the severity of colitis 14 and 21 days after induction of colitis between the capsaicin-pretreated group and the vehicle group. These data suggest that, in this model, sensory nerves have an important protective function in the acute and subacute phases of inflammation but do not seem to play a significant role in the later stages of chronic inflammation. Topics: Animals; Calcitonin Gene-Related Peptide; Capsaicin; Colitis; Colon; Intestinal Diseases; Intestinal Mucosa; Male; Neurons, Afferent; Peroxidase; Rats; Rats, Sprague-Dawley; Substance P; Ulcer; Wound Healing | 1996 |
Evaluation of the role of mast cells in the progression of acetic acid-induced colitis in mice.
Mast cells are widely distributed in the gastrointestinal mucosa. However, their role in the pathogenesis of inflammatory bowel disease remains unsettled. The aim of the present study is to clarify the relative importance of mast cells in the progression of acetic acid-induced colitis in mice.. Mast cell-deficient W/Wv and their normal littermate +/+ mice were given intrarectal administration of 5% acetic acid. The severity of colonic damage, the number of mast cells, and myeloperoxidase (MPO) activities in the colonic tissues were examined.. The severity of colonic damage was comparable between W/Wv and +/+ mice. In both groups of animals kinetic changes of the severity of the mucosal damage agreed well with that of MPO activities in the colonic mucosa. Pretreatment with a mast cell stabilizer, ketotifen, did not affect the severity of colitis in +/+ mice.. These results discount, but do not disprove, the role of mast cells in the progression of acetic acid-induced colitis in mice. Topics: Acetic Acid; Animals; Colitis; Intestinal Mucosa; Ketotifen; Male; Mast Cells; Mice; Mice, Inbred Strains; Neutrophils; Peroxidase | 1996 |
Attenuation of the inflammatory response in an animal colitis model by neutrophil inhibitory factor, a novel beta 2-integrin antagonist.
Neutrophils are significant effector cells in acute inflammatory bowel disease. Recruitment of these cells is dependent on beta 2-integrin-mediated adhesion and transmigration. The efficacy of neutrophil inhibitory factor (NIF), an antagonist of the beta 2-integrin CD11b/CD18, in ameliorating inflammation was tested in an animal model of acute colitis.. Immune-complex colitis was induced in groups of rabbits by using various formalin concentrations (2%, 0.75%, and 0.5%). Animals were treated with rNIF, 10 mg/kg. After they had been killed the mucosal appearance was scored, and tissue saved for histology and quantitation of myeloperoxidase (MPO), leukotriene B4 (LTB4), prostaglandin E2 (PGE2), and thromboxane B2 (TXB2).. In the 2% formalin group therapy with rNIF resulted in lower LTB4 (p < 0.05) levels. For the 0.75% and 0.5% groups, MPO was lower with rNIF treatment (p < 0.03 and p < 0.05, respectively), as were LTB4 concentrations (both, p < 0.04). PGE2 and TXB2 levels remained unchanged. Histology showed polymorphonuclear cell infiltration to be reduced by rNIF in the 2% and 0.75% formalin-treatment groups (p < 0.05).. These results suggest that blockade of CD11b/CD18-mediated mucosal neutrophil recruitment may form part of a strategy for targeted therapeutic intervention in inflammatory bowel disease. Topics: Acute Disease; Animals; CD18 Antigens; Colitis; Disease Models, Animal; Eicosanoids; Formaldehyde; Glycoproteins; Helminth Proteins; Integrins; Male; Membrane Proteins; Peroxidase; Rabbits; Recombinant Proteins | 1996 |
Presence of immunocytes and sulfidopeptide leukotrienes in the inflamed guinea pig distal colon.
This study examined whether the immunocyte recruitment associated with a mild inflammatory state induced by acetic acid would produce detectable sulfidopeptide leukotriene (LT) levels from colonic tissues or in dialysates. Histological examination and measurements of peroxidase activities of inflamed tissues indicated edema, hyperplasia and neutrophil infiltration. Significant elevated LTB4 and prostaglandin E2(PGE2) levels were found but only slight elevations in sulfidopeptide LTs occurred. A slight elevation in eosinophil peroxidase indicated that eosinophil infiltration also occurred. The increase in sulfidopeptide LT levels appeared insufficient by itself to alter secretory responses in the distal colon. However, combined with other immunocyte products such as PGs, the sulfidopeptide LTs may influence the symptomology of inflammatory bowel disease. Topics: Acetic Acid; Animals; Calcimycin; Calcium; Colitis; Eosinophil Peroxidase; Eosinophils; Guinea Pigs; Intestinal Mucosa; Ionophores; Leukotrienes; Male; Neutrophils; Ovalbumin; Peroxidase; Peroxidases | 1996 |
Bacterial peptides enhance inflammatory activity in a rat model of colitis.
Bacterial products released within the gut lumen may alter the course of inflammatory bowel lesions. The effect of intraluminal N-formyl methionyl-leucyl-phenylalanine on mucosal release of inflammatory mediators was investigated in normal and colitis rats (at 1 and 7 days after induction of colitis by trinitrobenzenesulfonic acid). Under anesthesia, the distal colon was perfused using an isosmotic solution with or without synthetic N-formyl methionyl-leucyl-phenylalanine (100 nmol/ml). Effluents were assayed for eicosanoid (PGE2, TXB2 and LTB4) concentration. Myeloperoxidase activity was measured in colonic wall homogenates. In normal rats, peptide perfusion did not change mucosal release of PGE2, TXB2 and LTB4. Colitic rats showed high baseline release of eicosanoids. The peptide did not further increase PGE2 and TXB2 release, but significantly stimulated LTB4 both on days 1 and 7 after induction of colitis. Rats with high myeloperoxidase activity in the colonic wall showed a marked LTB4 response to the peptide. Finally, peptide perfusion increased tissue myeloperoxidase activity in colitis at day 7 but not in colitis at day 1 or in normal rats. In conclusion, bacterial products may activate inflammation. This mechanism of lumen-wall interaction might be involved in the perpetuation of inflammatory lesions of the colonic mucosa. Topics: Animals; Colitis; Dinoprostone; Disease Models, Animal; Eicosanoids; Intestinal Mucosa; Leukotriene B4; Male; N-Formylmethionine Leucyl-Phenylalanine; Peroxidase; Rats; Rats, Sprague-Dawley; Thromboxane B2; Trinitrobenzenesulfonic Acid | 1996 |
Exudative and absorptive permeability in different phases of an experimental colitis condition.
Increased intestinal 'permeability' in inflammatory bowel disease and in animal models of this disease has been reported. This study asks if permeability changes are bidirectional and parallel cellular inflammation.. In rats acute inflammatory cell infiltration (ICI) was induced in an excluded bowel loop by instillation of 4% acetic acid. Plasma exudation was investigated by intravenous infusion of 125I-albumin and determination of radioactivity in loop perfusates. Absorption was measured by placing 51Cr-ethylenediaminetetraacetic acid in the loop and counting total radioactivity appearing in urine over 24 h.. Acute ICI was induced with acetic acid on day 4 but, as judged by ICI and histology, recovered by day 14. Acetic acid treatment resulted in increased absorption on day 4, which return to control levels by day 14. Acetic acid treatment resulted in increased plasma exudation on day 4, which remained increased on day 14.. Absorption and exudation changes are not necessarily bidirectional, and ICI may not be required for significant and sustained plasma exudation to take place. We suggest that the exudative response reflects a 'functional inflammation' that may occur and be important also in the absence of the traditional indices of bowel inflammation. Topics: Acetic Acid; Animals; Cell Membrane Permeability; Chromium Radioisotopes; Colitis; Disease Models, Animal; Edetic Acid; Exudates and Transudates; Inflammatory Bowel Diseases; Intestinal Absorption; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Serum Albumin, Radio-Iodinated | 1996 |
Dissociation of temperature changes and anorexia after experimental colitis and LPS administration in rats.
The acute phase of inflammation induces both anorexia and fever. Because several analyses suggest a linkage between the meal size and body temperature, we assessed whether temperature changes were causal to anorexia in situations involving acute inflammation. Specifically, we evaluated whether elevations of body temperature could account for the reduced food intake after induction of experimental colitis [via intrarectal infusions of trinitrobenzene sulfonic acid (TNB)] or injection of 100 micrograms/kg lipopolysaccharide (LPS). Temperature was monitored telemetrically in rats via implanted temperature transmitters. TNB-treated rats demonstrated a 5-day anorexia that resulted specifically from a decrease in meal size. Although TNB-treated rats were hypothermic on the day of treatment, no other body temperature changes were noted. LPS reduced food intake and elevated temperature, but these two effects were uncorrelated temporally. Although these results do not identify the mechanisms of anorexia, the findings indicate clearly that the anorexia associated with the acute inflammatory response is not secondary to fever. Topics: Animals; Anorexia; Body Temperature; Body Weight; Colitis; Eating; Feeding Behavior; Lipopolysaccharides; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1996 |
Application of natural products in experimental models of intestinal inflammation in rats.
Topics: Acetic Acid; Alkaline Phosphatase; Animals; Biomarkers; Colitis; Disease Models, Animal; Humans; Inflammatory Bowel Diseases; Leukotriene B4; Peroxidase; Quercetin; Rats; Rutin; Trinitrobenzenesulfonic Acid | 1996 |
Previous inflammation alters the response of the rat colon to stress.
Patients with inflammatory bowel disease have symptoms of irritable bowel syndrome (IBS) with a higher than expected prevalence. Stress is an important factor in the pathogenesis of IBS. Thus, previous inflammation may predispose to IBS by rendering the bowel more susceptible to the impact of stress. The aim of this study was to examine the effect of previous colitis on stress-induced responses in rats.. Acute colitis was induced in rats by intrarectal administration of trinitrobenzene sulfonic acid (TNBS), and the rats were allowed to recover for 6 weeks before application of mild restraint stress for 3 consecutive days. In vitro measurements included myeloperoxidase activity, plasma corticosterone levels, interleukin 1 beta messenger RNA expression, and [3H]noradrenaline release from the myenteric plexus.. Six weeks after administration of TNBS, stress caused a significant increase in myeloperoxidase activity in TNBS-treated rats but not in stressed controls; plasma corticosterone responses were similar. Stress also caused an exaggerated and significant suppression of [3H]noradrenaline release in TNBS-treated stressed rats compared with stressed controls. This was accompanied by a significant decrease in interleukin 1 beta messenger RNA expression in the colon.. Previous colitis rendered the colon more susceptible to effects of stress on enteric nerve function and also increased some parameters of inflammation in response to stress. Topics: Animals; Colitis; Colon; Corticosterone; Interleukin-1; Male; Norepinephrine; Peroxidase; Rats; Rats, Inbred WKY; Rats, Sprague-Dawley; Stress, Physiological; Trinitrobenzenesulfonic Acid | 1996 |
Efficacy of recombinant granulocyte colony-stimulating factor (rhG-CSF) in experimental colitis.
Inflammatory bowel disease is associated with mucosal neutrophil recruitment and activatation, mediated in part by arachidonic acid metabolites. G-CSF attenuates the immune response to sepsis and ameliorates glycogen storage disease Ib-related colitis. These actions may be effected through the shedding of neutrophil adhesion molecules, or inhibition of proinflammatory mediator synthesis. Immune complex colitis was used to evaluate the effect of rhG-CSF on colonic mucosal inflammation, neutrophil recruitment and the generation of eicosanoids. Immune complex colitis was induced in White New Zealand rabbits. Animals were pretreated with rhG-CSF either 24 h before induction, or at induction, with dosages of 50 and 200 micrograms/kg. rhG-CSF caused a time- and dose-dependent neutrophilia in all animals. Pretreatment with rhG-CSF resulted in increased tissue myeloperoxidase levels, despite a histologically similar mucosal polymorphonuclear cell infiltrate between treated and control colitis groups. Leukotriene B4 (LTB4) and thromboxane B2 (TXB2) dialysis fluid levels were lower in treated animals, in particular in the groups receiving two doses (LTB4: both P < 0.01; TXB2: both P < 0.01. Prostaglandin E2 (PGE2) levels in dialysis fluid of the rhG-CSF-treated animals showed no difference from controls. In this model of experimental colitis, high-dose therapy with G-CSF resulted in a marked decrease of proinflammatory mediators, but mucosal generation of the protective PGE2 was preserved. These results suggest that prolonged high-dose therapy with G-CSF may have anti-inflammatory effects in colitis. Topics: Animals; Antigen-Antibody Complex; Colitis; Dialysis Solutions; Eicosanoids; Granulocyte Colony-Stimulating Factor; Intestinal Mucosa; Leukocyte Count; Male; Organ Specificity; Peroxidase; Rabbits; Recombinant Proteins | 1996 |
Induction of nitric oxide synthase and concomitant suppression of superoxide dismutases in experimental colitis in rats.
Reactive oxygen species are thought to play an important role in some bowel diseases. In order to evaluate the participation of nitric oxide and superoxide in such diseases, we examined the expression of nitric oxide synthase (NOS) and superoxide dismutase (SOD) as well as their activities in whole excised colons of rats with colitis induced by intralumenal administration of 2,4,6-trinitrobenzenesulfonic acid. A marked increase in the inducible form of NOS mRNA was detected and NOS activity was coincidentally augmented in the group administered unbuffered TNBS (pH 1.0), in which severe inflammation was revealed by microscopic examination and myeloperoxidase activity of invading neutrophils in the tissues. The levels of the Mn- and Cu,Zn-SOD proteins as well as SOD activity were suppressed, although expression of the Mn-SOD mRNA was enhanced in colitis tissues. The elevation of NOS activity and the suppression of SOD activity occurred concomitantly at the stage of severe inflammation. This would increase peroxynitrite formation from superoxide and nitric oxide and enhance the tissue damage in experimental colitis. Topics: Animals; Blotting, Northern; Colitis; Colon; Disease Models, Animal; Enzyme Induction; Female; Gene Expression Regulation, Enzymologic; Neutrophils; Nitrates; Nitric Oxide Synthase; Nitrites; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; RNA, Messenger; Superoxide Dismutase; Trinitrobenzenesulfonic Acid | 1995 |
The selective beneficial effects of nitric oxide inhibition in experimental colitis.
We investigated the involvement of nitric oxide in trinitrobenzene-sulfonic acid (TNB) colitis. Every 24 h after TNB, rats were orally dosed with NG-nitro-L-arginine methyl ester (L-NAME; 30 mg/kg), NG-nitro-D-arginine methyl ester (D-NAME), or water, and food intake, body weight, and plasma nitrite levels were measured. On day 6, colonic nitric oxide synthase and myeloperoxidase (MPO) activity, histology, intestinal muscle growth, NADPH-diaphorase, and myenteric nerve function were assessed. Food intake and body weight were reduced during the first 72 h of colitis. On day 6 post-TNB, a fourfold increase in mucosal nitric oxide synthase, a 30-fold increase in MPO, and a fivefold elevation in plasma nitrite were measured. Smooth muscle hyperplasia and hypertrophy in both colonic muscle layers, numerous diaphorase-positive macrophages in the myenteric plexus, and a suppression of myenteric nerve function were also observed. Unlike D-NAME, oral L-NAME reduced MPO and intestinal muscle hyperplasia by > 90%. Likewise, plasma nitrite and colonic nitric oxide synthase were reduced by > 70%. L-NAME completely prevented macrophage infiltration into the muscle. Conversely, it had no effect on anorexia or intestinal smooth muscle hypertrophy, nor did it affect suppressed myenteric nerve neurotransmitter release. These results demonstrate the selective transmural protective effects of L-NAME in the inflamed colon, implicating nitric oxide as a mediator. Topics: Amino Acid Oxidoreductases; Animals; Arginine; Body Weight; Colitis; Colon; Eating; Hyperplasia; Hypertrophy; Intestines; Male; Muscle, Smooth; Myenteric Plexus; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Norepinephrine; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1995 |
Sulfhydryl blocker-induced rat colonic inflammation is ameliorated by inhibition of nitric oxide synthase.
Sulfhydryl compounds are essential in maintaining mucosal integrity, and nitric oxide may contribute to tissue injury. The aim of this study was to characterize experimental colitis induced by a sulfhydryl blocker.. Colitis was induced in rats by intracolonic administration of 0.1 mL 3% iodoacetamide with and without addition of 0.1 mg/mL NG-nitro-L-arginine methyl ester (L-NAME) to the drinking water. After death, the distal colonic segment was resected and weighed, and mucosal inflammatory mediator, myeloperoxidase, and NO synthase activities were determined.. Iodoacetamide induced multifocal mucosal erosions and ulceration that were present for up to 1 week. At 3 weeks, the mucosa was almost intact. Colonic wet weight was maximal at 7 days. Myeloperoxidase activity and NO generation were increased in the first 72 hours, and NO synthase activity and prostaglandin E2 generation were increased up to 21 days. Leukotriene B4 and leukotriene C4 generation were increased up to 14 days. One week after iodoacetamide plus L-NAME treatment, lesion area was reduced by 85% and NO synthase activity by 52%.. Inflammatory mediators have an important contribution to the pathogenesis of colonic injury induced by a sulfhydryl alkylator. The protective effect of L-NAME indicates that NO contributes to tissue injury and that its modulation may be a novel approach to treat inflammatory bowel disease. Topics: Amino Acid Oxidoreductases; Animals; Arginine; Colitis; Colon; Dinoprostone; Intestinal Mucosa; Iodoacetamide; Leukotriene B4; Leukotriene C4; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Sprague-Dawley | 1995 |
Colitis reduces short-circuit current response to inflammatory mediators in rat colonic mucosa.
Inflammatory mediators may contribute to the diarrhea associated with colitis. Although the secretory action of such mediators is reported in normal tissue, there is little information regarding their effects on inflamed tissue. We examined the short-circuit current response (Isc) to these mediators, in mitomycin-C (MC)-induced colitis, a model with histological similarities to colitis in man. Rats were injected once with MC (3.25 mg/kg, intraperitoneally) or vehicle. The colons were removed three and seven days later and mounted, devoid of muscularis, in Ussing chambers for measurement of Isc, potential difference (PD), and resistance (Rt). MC-treated rats had diarrhea after three days, and microscopic studies revealed colonic inflammation. There were no significant differences in Rt, PD, and Isc between control and MC-treated tissues at three and seven days. Maximal increases in Isc to bradykinin, prostaglandin E1, carbachol, substance P, and serotonin were depressed at three and/or seven days after MC. The Isc response to theophylline was not affected. Theophylline activates secretion through an intracellular mechanism; the other agonists act by interaction with epithelial cell membranes. Therefore, the mechanism for the decreased Isc may result from uncoupling of receptors to second-messenger systems or desensitization of receptor-linked secretory mechanisms. Topics: Alprostadil; Animals; Anions; Bradykinin; Carbachol; Colitis; Intestinal Mucosa; Male; Mitomycin; Neutrophils; Patch-Clamp Techniques; Peroxidase; Rats; Rats, Sprague-Dawley; Second Messenger Systems; Secretory Rate; Serotonin; Substance P; Theophylline; Time Factors | 1995 |
Effects of FK506 on an experimental model of colitis in rats.
To assess the effects of FK506, a newly developed immunosuppressant, on experimental colitis in rats.. Experimental colitis was induced by a single colonic instillation of hapten 2,4,6-trinitrobenzene sulphonic acid (TNB) in anaesthetized rats. Rats received 30 mg TNB dissolved in 0.25 mL of 50% ethanol, and were sacrificed on day 5 following 4 days dosing with FK506 (0.25, 0.5, 1.0, 2.0 mg/kg, s.c.) or vehicle. Mucosal prostanoid concentrations were determined using high performance liquid chromotography. Tissue myeloperoxidase activities were measured. The effects of FK506 on superoxide radical formation by neutrophils in both rats and humans were also estimated in vitro.. Administration of FK506 significantly reduced the colonic damage in a dose-dependent manner. Activities of myeloperoxidase and concentrations of 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), PGF2 alpha and PGE2 in colonic tissue increased significantly following induction of experimental colitis, however, FK506 did not affect these changes. FK506 reduced stimulant-induced superoxide radical formation by neutrophils in rats and humans.. FK506 decreased superoxide radical generation by neutrophils, which might contribute to the lessening of colonic damage in this model. Topics: Animals; Colitis; Colon; Male; NADH, NADPH Oxidoreductases; NADPH Oxidases; Peroxidase; Rats; Rats, Wistar; Superoxides; Tacrolimus | 1995 |
Activated immunocompetent cells in rat colitis mucosa induced by dextran sulfate sodium and not complete but partial suppression of colitis by FK506.
Administration of dextran sulfate sodium (DSS) solutions to rats induced colitis which resembled mucosal lesions of human ulcerative colitis. Recent reports have shown that some cytokines are related to the pathogenesis of ulcerative colitis. In the present report, we describe the production of two cytokines in colitis mucosa in this DSS model. Using a cytotoxicity assay and a radioimmunoassay, we observed significant increases in levels of tumor necrosis factor-alpha (TNF-alpha) in the colitis mucosa and detected interleukin-1 alpha in the mucosa of 3 of 5 DSS rats and an increase in TNF-alpha had a tendency to be inhibited by treatment with FK506. Immunohistochemical investigation of DSS mucosa showed that the number of activated T cells increased at the earlier phase of inflammation. Luminol-dependent chemiluminescence values and myeloperoxidase activities were increased in the late phase of colitis and were suppressed by the FK506 treatment. These findings may support the role of TNF-alpha and T-cell activation in the pathogenesis of DSS colitis. Topics: Animals; Colitis; Dextran Sulfate; Interleukin-1; Intestinal Mucosa; Luminescent Measurements; Lymphocyte Activation; Male; Peroxidase; Rats; Rats, Wistar; T-Lymphocytes; Tacrolimus; Tumor Necrosis Factor-alpha | 1995 |
Annexin 1 is overexpressed and specifically secreted during experimentally induced colitis in rats.
Annexin 1 is a protein induced by glucocorticoids endowed with extracellular anti-inflammatory properties. In this study, the local expression and secretion of annexins 1-6, in rat proximal colon, were studied at different times after intracolonic administration of 30 mg trinitrobenzenesulfonic acid in 50% ethanol. Secretion was identified by incubating colonic tissues in a culture medium. The expression of annexins was detected by immunoblotting in tissue homogenates and incubation media. Inflammatory stages were evaluated by measuring myeloperoxidase activity. Annexin 1 expression in colons increased after trinitrobenzenesulfonic acid treatment and was maximal between days 1 to 9, during the cellular stage of the inflammation that corresponded to maximal myeloperoxidase activity. From 12 h to 9 days after trinitrobenzenesulfonic acid/ethanol treatment, annexin 1 was specifically secreted. Annexin 3 was also overexpressed during the cellular stage, but the expression of annexins 2, 4, 5, and 6 was unchanged; none of these annexins were secreted. Annexin 1 was shown to be physiologically secreted because its release was specific, abundant, and not correlated with cellular lysis. Annexin 1 may be considered as a putative candidate in the control of the gut inflammatory processes. Topics: Animals; Annexin A1; Annexins; Colitis; Extracellular Space; Kinetics; Male; Molecular Weight; Peroxidase; Rats; Rats, Wistar; Time Factors; Trinitrobenzenesulfonic Acid | 1995 |
Transmucosal potential difference in experimental colitis in rats.
Colon transmucosal potential difference (TPD), macro- and microscopic lesions, myeloperoxidase activity, and leukotriene levels were studied after the induction of experimental colitis in the rat. Forty-three male Wistar rats were subjected to the instillation of 200 mg/ml 2,4,6-trinitrobenzenesulfonic acid (TNB) solution through a rectal cannula. TPD measurements were made at different distances from the anus before and 24 h and one, two, three, and four weeks after lesion induction. Leukotriene B4 levels were assayed by intracolonic dialysis 24 h and one, two, three and four weeks after lesion induction. Macro- and microscopic evaluations were made of the bowel lesions, and myeloperoxidase activity was assayed. The mean basal TPD was -46.06 mV at 1 cm from the anus, and +10.86 mV in the proximal colon. Twenty-four hours after lesion induction the values proved markedly positive. This was correlated with an abrupt increase in LTB4 levels and myeloperoxidase activity. After one week the TPD values exhibited a greater electronegativity, returning to basal values by the fourth week after lesion induction. This coincided with an improved macroscopic lesion index, LTB4 levels, and myeloperoxidase activity. In conclusion, TPD is a useful indicator of acute colonic lesions and correlates well with LTB4 and myeloperoxidase assays. Moreover, the parameter is able to delimit lesion evolution, reflecting possible ad integrum restoration of the bowel mucosa. Topics: Animals; Colitis; Colitis, Ulcerative; Fibrosis; Intestinal Mucosa; Leukotriene B4; Leukotrienes; Male; Membrane Potentials; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 1995 |
A stable nitroxide radical effectively decreases mucosal damage in experimental colitis.
TEMPOL, a cyclic nitroxide stable radical blocks biological damage by breaking chain reactions through termination reaction with free radicals, and by inhibiting the catalytic effect of transition metals. This study tested its protective effect on two models of experimental colitis as free radicals play an important part in their pathogenesis. TEMPOL was given intragastrically immediately after induction of colitis with acetic acid or trinitrobenzene sulphonic acid (TNB) and mucosal damage was assessed one, three, or seven days later. Cellular partition of TEMPOL was determined by electron paramagnetic resonance spectroscopy. In vitro experiments showed that TEMPOL immediately penetrates colonic mucosa and, following its intragastric administration, it persists in both gastric and colonic mucosa for several hours. Intragastric administration of TEMPOL, 0.5 g/kg/bw, immediately after intracaecal administration of 5% acetic acid significantly decreased mucosal lesion area, myeloperoxidase activity, and leukotriene B4 and C4 generation when assessed 24 hours after damage induction. Intragastric administration of TEMPOL, 0.5 g/kg/bw, immediately after intracolonic administration of 30 mg TNB in 0.25 ml 50% ethanol, and once daily thereafter, significantly decreased mucosal lesion area assessed after one, three, and seven days, having no effect on LTC4 generation and affecting colonic weight, myeloperoxidase activity, and LTB4 generation only sporadically. In conclusion, TNB and acetic acid induced colitis can be pharmacologically manipulated by TEMPOL. TEMPOL may be beneficial in the treatment or prevention of inflammatory bowel disease. Topics: Acetates; Animals; Antioxidants; Colitis; Cyclic N-Oxides; Disease Models, Animal; Electron Spin Resonance Spectroscopy; Intestinal Mucosa; Leukotriene B4; Leukotriene C4; Lipoxygenase; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Spin Labels; Time Factors; Trinitrobenzenesulfonic Acid | 1995 |
Reactivation of hapten-induced colitis and its prevention by anti-inflammatory drugs.
Administration of a hapten together with a barrier breaker, such as ethanol, into the colon of a rat results in extensive mucosal injury and inflammation that bears some similarity to the colonic inflammation characterizing inflammatory bowel disease in humans. This inflammation and injury gradually subsides over the weeks after its induction. We have attempted to determine whether this colitis can be "reactivated" by administration of the hapten systemically weeks after its initial intracolonic administration. Six weeks after intracolonic administration of trinitrobenzene sulfonic acid (the hapten) in a vehicle of 50% ethanol, most of the colonic injury and inflammation had subsided. Intravenous administration of the hapten at 24-h intervals over 3 days resulted in reactivation of the colitis, with significant increases in macroscopic and histological damage scores (mucosal injury and inflammation) and a significant increase in granulocyte infiltration, as measured by tissue myeloperoxidase (MPO) infiltration, as measured by tissue myeloperoxidase (MPO) activity. The increase in MPO activity occurred only in the region previously exposed to the hapten. Intravenous administration of saline did not reactivate the colitis, nor did intravenous administration of the hapten to rats previously treated intracolonically with saline or the ethanol vehicle. Reactivation of colitis by hapten administration was not accompanied by activation of mucosal mast cells. Treatment with dexamethasone prevented the increase in colonic damage score and MPO activity elicited by intravenous hapten administration. Cyclosporin A reduced MPO activity, and 5-aminosalicylic acid reduced the colonic damage score, whereas lidocaine and two inhibitors of leukotriene synthesis did not significantly affect either of these parameters.(ABSTRACT TRUNCATED AT 250 WORDS) Topics: Animals; Anti-Inflammatory Agents; Chymases; Colitis; Colon; Haptens; Male; Peroxidase; Rats; Rats, Wistar; Recurrence; Serine Endopeptidases; Trinitrobenzenesulfonic Acid | 1995 |
Anti-CD11b/CD18 antibodies reduce inflammation in acute colitis in rats.
The influx of monocytes and neutrophils into the inflamed tissue could be an important aspect in the pathogenesis of inflammatory bowel disease (IBD). A membrane protein involved in the monocyte/neutrophil adherence to endothelium is CD11b/CD18 or alpha M beta 2 (complement receptor type 3 = CR3). In the present study the role of CD11b/CD18 in experimental IBD was studied by treatment with ED7 and OX42, two MoAbs against CD11b/CD18. Colitis was induced in rats by a single, rectal administration of 30 mg 2,4,6-trinitrobenzene sulfonic acid (TNBS) dissolved in ethanol 30%. Two hours before and 3 days after induction of colitis, the animals were given an i.v. dose of 0.5 mg of either ED7 or OX42 in 1 ml PBS. Controls received PBS or an irrelevant MoAb. Four days after the last treatment with the antibodies, the rats were killed, and macroscopic damage scores of the colon were determined. Macrophages and granulocytes were studied by immunohistochemistry and quantified by Interaktives Bild Analysen System (IBAS), and myeloperoxidase (MPO) activity in colonic tissue was measured. After treatment with ED7 and OX42 the mean damage score of the colon was reduced from 4.2 in IBD animals to 1.0 and 1.3, respectively. Smaller areas of ulcerations and a decrease in the number of ulcerations were observed compared with PBS-treated rats. Furthermore, the amount of infiltrating monocytes and leucocytes in the submucosa was enormously reduced, as well as MPO activity in the colonic tissue. These results show that treatment with MoAbs against CD11b/CD18 reduces clinical signs of experimental IBD in rats by a partial blockade of infiltrating macrophages and granulocytes. Topics: Acute Disease; Animals; Antibodies; Antibodies, Monoclonal; CD18 Antigens; Colitis; Granulocytes; Immunotherapy; Macrophage-1 Antigen; Macrophages; Male; Peroxidase; Rats; Rats, Wistar | 1995 |
Experimental colitis alters myenteric nerve function at inflamed and noninflamed sites in the rat.
Studies in inflammatory bowel disease have shown extensive structural abnormalities in the enteric nervous system of inflamed and noninflamed gut; however, functional correlates are lacking. The aim of this study was to determine the effect of colitis on myenteric nerve function at inflamed and noninflamed sites in rat intestine.. Tritiated noradrenaline release was measured from longitudinal muscle myenteric plexus preparations from the distal and transverse colon and terminal ileum of rats with colitis induced by trinitrobenzene sulfonic acid or Trichinella spiralis larvae.. As characterized by myeloperoxidase activity and histology, both models induced inflammation restricted to the distal colon. In distal colon in trinitrobenzene sulfonic acid colitis, KCl- or electrical field stimulation-evoked 3H release was suppressed by 56% and 60%, respectively; in T. spiralis-infected rats, the KCl-evoked release was suppressed by 58%. 3H release was also suppressed by similar magnitudes in noninflamed transverse colon and terminal ileum of each model.. Experimental distal colitis alters myenteric nerve function in inflamed distal colon and noninflamed gut regions. These changes are independent of the manner in which colitis is induced and provide a basis for the extensive disruption of physiological function observed in inflammatory bowel disease. Topics: Adrenergic Fibers; Animals; Colitis; Colon; Ileum; Intestinal Diseases, Parasitic; Male; Myenteric Plexus; Norepinephrine; Peroxidase; Rats; Rats, Sprague-Dawley; Trichinella spiralis; Trichinellosis; Trinitrobenzenesulfonic Acid | 1995 |
Anti-inflammatory effects of CGP 47969A, a novel inhibitor of proinflammatory cytokine synthesis, in rabbit immune colitis.
Proinflammatory cytokines such as interleukin (IL) 1, IL-8, and tumor necrosis factor (TNF) have been implicated as primary mediators of intestinal inflammation. The aim of the present study was to determine the effects of a novel cytokine antagonist (CGP 47969A) in a rabbit model of acute colitis.. Colitis was induced using the formalin-immune complex technique. Animals were pretreated intrarectally with CGP 47969A (30, 10, or 3 mg/kg), hydrocortisone (0.8 mg/kg), or vehicle (4 mL saline) 2 hours before the induction of colitis and twice daily thereafter until death 48 hours after the induction of colitis. The severity of inflammation of colonic tissue was assessed using histological analysis and myeloperoxidase activity assay, and IL-1 alpha, IL-8, TNF-alpha, and IL-1 receptor antagonist levels were determined.. Compared with vehicle, CGP 47969A (10 mg/kg) significantly reduced the acute inflammatory index by 58%, edema by 67%, necrosis by 99%, and myeloperoxidase activity by 49% (all P < 0.02) with efficacy similar to that of steroids. These effects were associated with a significant inhibition of colonic IL-1 alpha and IL-8 by 56% and 90%, respectively (p < 0.01).. Administration of CGP 47969A reduces inflammation and tissue damage in rabbit immune complex colitis through mechanisms involving the inhibition of mucosal proinflammatory cytokines. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Cytokines; Hydrocortisone; Immune Complex Diseases; Interleukin-1; Interleukin-8; Male; Peroxidase; Piperazines; Rabbits | 1995 |
Disruption of colonic electrolyte transport in experimental colitis.
The time course of disturbances of distal colonic electrolyte transport during experimental colitis in rats was compared with changes in the severity of inflammation and epithelial disruption. Colitis was induced by intracolonic administration of trinitrobenzenesulfonic acid (TNBS). At time points from 1 day to 8 wk thereafter, Na+ and Cl- transport was studied under short-circuited conditions in Ussing chambers, three indexes of tissue inflammation were measured, and histology was performed. Net absorption of Na+ and Cl- was abolished at 1 and 4 days after induction of colitis, but recovered to control levels by 1 wk. All unidirectional electrolyte fluxes were elevated at 1 day and fell significantly, generally to control levels, by 4 days. The indexes of inflammation, tissue myeloperoxidase, and synthetic capacities for prostaglandin E2 and leukotriene B4 were all significantly elevated from 1 day to 2 wk post-TNBS. At 1 and 4 days, there was widespread epithelial necrosis, and reepithelialization was consistently seen by 2 wk. In additional studies, 2 wk post-TNBS, the short-circuit current response to 3-isobutyl-1-methylxanthine was reduced compared with controls. These data suggest that abolition of electrolyte absorption early in this experimental colitis was largely attributable to epithelial damage. Despite demonstrable tissue inflammation 2 wk post-TNBS, basal electrolyte transport was not impaired, while the colitic epithelium was hyporesponsive to a Cl- secretagogue. The data also suggest that gross barrier function was restored prior to reepithelialization. Topics: Animals; Biological Transport; Colitis; Colon; Dinoprostone; Electrolytes; Leukotriene B4; Male; Peroxidase; Rats; Rats, Wistar; Time Factors; Trinitrobenzenesulfonic Acid | 1995 |
Colonic delivery of dexamethasone from a prodrug accelerates healing of colitis in rats without adrenal suppression.
Dexamethasone-beta-D-glucuronide, a colon-specific prodrug of dexamethasone, may be useful in the treatment of ulcerative colitis and Crohn's colitis. The aim of this study was to evaluate colonic delivery and efficacy of this prodrug in the rat.. Distribution of dexamethasone in luminal contents and tissues of the gastrointestinal tract and in plasma was measured after oral administration of dexamethasone-beta-D-glucuronide or free dexamethasone. Efficacy of the prodrug and free drug was tested in an acetic acid-induced rat colitis model. Healing of induced colitis was assessed by measuring net intestinal fluid absorption, colonic surface area of ulceration, histology, and myeloperoxidase activity. Glucocorticosteroid toxicity was evaluated with serum corticosterone and plasma adrenocorticotropic hormone levels.. The drug delivery index (a measure of relative targeting efficiency) was 6.7 and 8.6 in the cecal and colonic mucosa, respectively. The prodrug was significantly more potent than free drug in improving net colonic fluid absorption while significantly reducing surface area of ulceration and histological grade in colitic rats. Treatment with free dexamethasone significantly reduced serum corticosterone levels to subnormal levels, and treatment with the prodrug maintained serum corticosterone and plasma adrenocorticotropic hormone levels near control levels.. The prodrug dexamethasone-beta-D-glucuronide delivers efficacious amounts of dexamethasone to the large intestine from lower doses than free dexamethasone. Topics: Adrenal Cortex; Adrenocorticotropic Hormone; Animals; Colitis; Colon; Corticosterone; Dexamethasone; Glucuronates; Intestinal Absorption; Male; Peroxidase; Prodrugs; Rats; Rats, Sprague-Dawley; Tissue Distribution | 1995 |
Spontaneous intestinal inflammation and nitric oxide metabolism in HLA-B27 transgenic rats.
It has been reported that transgenic rats expressing the HLA-B27 and the beta 2- microglobulin genes develop spontaneous gastrointestinal (GI) inflammation; however, no systematic or quantitative evaluation of this GI inflammation has been reported. Therefore, the objective of this study was to characterize quantitatively the GI injury and inflammation observed in commercially available HLA-B27 transgenic rats.. HLA-B27 rats and Fisher 344 male controls were used for these studies. Gastric, ileal, and colonic blood-to-lumen clearances of 51Cr-ethylenediaminetetraacetic acid, tissue myeloperoxidase activities, and wet/dry ratios of the various tissues as well as plasma nitrate and nitrite levels were quantified for each control and transgenic animal.. Spontaneous ileitis and colitis developed in 5 of 10 HLA-B27 transgenic rats beginning at approximately 17 weeks of age and persisting for an additional 13 weeks. Increases in mucosal permeability and myeloperoxidase activities as well as histological analysis showed intestinal injury and chronic inflammation. Plasma levels of nitrate and nitrite, the stable decomposition products of nitric oxide, were found to be significantly enhanced (fourfold) only in those rats that developed the intestinal inflammation.. The chronic ileitis and colitis observed in HLA-B27 transgenic rats seems to be associated with enhanced NO metabolism. Topics: Animals; Animals, Genetically Modified; Colitis; Colon; Disease Models, Animal; Edetic Acid; Gastric Mucosa; HLA-B27 Antigen; Ileitis; Ileum; Inflammatory Bowel Diseases; Intestinal Mucosa; Male; Nitrates; Nitric Oxide; Nitrites; Permeability; Peroxidase; Rats; Rats, Inbred F344; Stomach | 1995 |
BPC-15 reduces trinitrobenzene sulfonic acid-induced colonic damage in rats.
The effect of BPC-15 (Booly Protection Compound-15) was evaluated in a rat model of colonic injury. A single intracolonic administration of trinitrobenzene sulfonic acid (TNBS) dissolved in ethanol induces severe colonic damage, which is characterized by areas of necrosis surrounded by areas of acute inflammation. The damage is associated with high myeloperoxidase (MPO) activity, mainly as a reflection of neutrophilic infiltration into the damaged tissue. In this study, 1 hr before a single intracolonic administration of 50 mg/kg of TNBS in 50% ethanol, the animals were treated with one of the following doses of BPC-15: 0.0001, 0.001, 0.01, 0.1, 1 or 10 nmol/kg administered i.p. or with a dose of 10 nmol/kg administered intracolonically. The animals were sacrificed 3 days later and the extent of colonic necrosis and hyperemia was measured with an image analyzer. The i.p. administration of BPC-15 significantly reduced the extent of TNBS-induced colonic damage in a dose-dependent manner. This was associated with a statistically significant and dose-dependent reduction in colonic tissue MPO activity. At the dose tested (10 nmol/kg), intracolonic administration of BPC-15 did not significantly reduce either the extent of the colonic damage or the increase in MPO activity induced by TNBS. In conclusion, this study showed that i.p. administration of BPC-15 reduced TNBS-induced colonic damage in rats. Topics: Amino Acid Sequence; Animals; Colitis; Male; Molecular Sequence Data; Peptide Fragments; Peroxidase; Proteins; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1995 |
Pharmacological activity of the second generation leukotriene B4 receptor antagonist, SC-53228: effects on acute colonic inflammation and hepatic function in rodents.
Inflammatory bowel disease is a chronic inflammatory disorder of the gastrointestinal tract that includes ulcerative colitis and Crohn's disease. Leukotriene B4 is thought to be a prominent proinflammatory mediator in these diseases, in that leukotriene B4 levels are increased in the colonic mucosa of inflammatory bowel disease patients and there is increased polymorphonuclear leukocyte infiltration of these tissues. SC-53228 [(+)-(S)-7-[3-[2(-cyclopropylmethyl)-3-methoxy-4- [(methylamino)carbonyl]phenoxy]propoxy]-3,4-dihydro-8-propyl-2H-1- benzopyran-2-propanoic acid], a second generation LTB4 receptor antagonist, was evaluated for therapeutic efficacy in a rodent model of acute colonic inflammation induced by short chain organic acids, as well as for effects on rodent liver. When given intracolonically to mice, SC-53228 inhibited neutrophil infiltration, assessed by myeloperoxidase (MPO) levels, with an ED50 value of 9 +/- 1.2 mg/kg. When given by gavage, SC-53228 inhibited neutrophil influx in colitic mice with an ED50 value of 30 mg/kg. These results were also confirmed histologically. Furthermore, high dose oral SC-53228 treatment had no effect on liver cytochrome P-450 content, fatty acyl CoA oxidase or liver weight in rats and mice. Together, these data suggest that SC-53228 may be efficacious orally and locally, as well as safe for use in trials for the medical management of IBD. Topics: Acyl-CoA Oxidase; Animals; Benzamides; Benzopyrans; Colitis; Colon; Cytochrome P-450 Enzyme System; Gemfibrozil; Liver; Male; Mice; Mice, Inbred ICR; Organ Size; Oxidoreductases; Peroxidase; Phenobarbital; Rats; Rats, Sprague-Dawley; Receptors, Leukotriene B4 | 1995 |
Effects of chronic nitric oxide synthase inhibition on TNB-induced colitis in rats.
Nitric oxide (NO) synthesis is increased in ulcerative colitis, but the role of NO in colitis is poorly understood. The present study employed Nw-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, in rats to evaluate the effect of NO on 2,4,6-trinitrobenzenesulphonic acid (TNB)-induced colitis. L-NAME solutions were placed in subcutaneous, osmotic mini-pumps which continuously released L-NAME at 0.042, 0.208, 0.417, or 1.667 mg kg-1 h-1. L-NAME dose-dependently enhanced lesions in TNB-induced colitis. The two higher doses of L-NAME significantly increased colonic mucosal damage, although there was slight, nonsignificant reduced lesion formation with the lowest dose of L-NAME. 0.042 mg kg-1 h-1. A single dose of L-NAME at 100 mg kg-1 subcutaneously injected daily in TNB-treated rats also increased lesions, and these ulcerogenic actions of L-NAME were reversed by L-arginine but not by D-arginine (both at 500 mg kg-1, s.c.). Only the highest dose of L-NAME (mini-pump) significantly depressed myeloperoxidase (MPO) activity. Faecal occult bleeding showed a close relationship with severity of colitis. These findings suggest that there may exist a balance between NO protective and aggressive effects. In TNB-induced colitis, antagonism of endogenous NO generation was intensified, whereas slight inhibition of NO synthesis reduced lesions. Variations in responses, related to timing or dose changes in L-NAME, may reflect the differences in inducible vs constitutive NO synthase isoforms. Topics: Animals; Arginine; Body Weight; Colitis; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Infusion Pumps, Implantable; Injections, Subcutaneous; Intestinal Mucosa; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1995 |
A glucocorticoid prodrug facilitates normal mucosal function in rat colitis without adrenal suppression.
Glucocorticoids remain the foundation of therapy for acute ulcerative colitis despite systemic side effects that limit their use. Prodrugs that selectively deliver glucocorticoids to the colon may lower the required dose and side effects. The aim of this study was to assess the efficacy of a newly synthesized glucocorticoid-dextran prodrug.. Novel glucocorticoid-dextran prodrug conjugates in which dexamethasone and methylprednisolone were attached to dextran were synthesized using the dicarboxylic acid linkers, succinate and glutarate. The efficacy of the dextran prodrug conjugates and their free glucocorticoids was tested in an acetic acid-induced model of colitis. Repair of the colitis and mucosal function was assessed by measuring net intestinal fluid absorption, macroscopic ulceration, and myeloperoxidase activity. Glucocorticoid toxicity was evaluated by measuring plasma adrenocorticotropic hormone and serum corticosterone levels.. The prodrug dexamethasone-succinate-dextran was nine times more potent and dexamethasone-glutarate-dextran three times more potent than free dexamethasone in accelerating mucosal repair. Similarly, methylprednisolone-succinate-dextran was four times more potent than free methylprednisolone. The dextran prodrug conjugates affected adrenocorticotropic hormone and corticosterone levels only at the highest doses in contrast to free dexamethasone and methylprednisolone, which caused marked adrenal suppression at all doses.. The results show that recently synthesized glucocorticoid-dextran prodrug conjugates can be administered orally to facilitate mucosal repair in rat colitis without adrenosuppression. Topics: Adrenal Glands; Adrenocorticotropic Hormone; Animals; Colitis; Colon; Corticosterone; Dextrans; Glucocorticoids; Intestinal Absorption; Intestinal Mucosa; Male; Peroxidase; Prodrugs; Rats; Rats, Sprague-Dawley | 1994 |
A budesonide prodrug accelerates treatment of colitis in rats.
Although oral glucocorticoids are the treatment of choice for moderate to severe ulcerative pancolitis, their systemic side effects and adrenal suppression account for considerable morbidity. An oral glucocorticoid-conjugate (prodrug), budesonide-beta-D-glucuronide, which is not absorbed in the small intestine but is hydrolysed by colonic bacterial and mucosal beta-glucuronidase to release free budesonide into the colon was synthesised. The objective of this study was to compare treatment with budesonide-beta-D-glucuronide with treatment with free budesonide by examining: (1) the healing of experimental colitis and (2) the extent of adrenal suppression. Pancolitis was induced with 4% acetic acid. Animals were then randomised to receive oral therapy for 72 hours with (1) budesonide-beta-D-glucuronide, (2) free budesonide, or (3) vehicle. Drug efficacy and colitic healing was determined by measuring gross colonic ulceration, myeloperoxidase activity, and in vivo colonic fluid absorption. Adrenal suppression was determined by measuring plasma adrenocorticotrophic hormone and serum corticosterone. Vehicle-treated colitis animals had gross ulceration, increased myeloperoxidase activity, and net colonic fluid secretion. Treatment with oral budesonide-beta-D-glucuronide accelerated all measures of colitis healing at a fourfold lower dose than did free budesonide. Furthermore, treatment with budesonide-beta-D-glucuronide did not result in adrenal suppression whereas free budesonide treatment did. A newly synthesised orally administered glucocorticoid-conjugate accelerates colitis healing with limited adrenal suppression. Development of an orally administered colon-specific steroid delivery system represents a novel approach to inflammatory bowel disease treatment. Topics: Acetates; Administration, Topical; Adrenal Glands; Animals; Anti-Inflammatory Agents; Budesonide; Colitis; Colon; Depression, Chemical; Glucocorticoids; Intestinal Absorption; Male; Peroxidase; Pregnenediones; Prodrugs; Random Allocation; Rats; Rats, Sprague-Dawley | 1994 |
Topical anticolitic efficacy and selectivity of the glucocorticoid budesonide in a new model of acetic acid-induced acute colitis in the rat.
To study the effect of local or parenteral administration of the glucocorticoid budesonide in the acetic acid-induced colitis model in the rat.. Colitis was induced in an exteriorized colonic segment by administration of 4% acetic acid for 15 s. Four days later, this colonic segment with colitis was examined using a morphological scoring system, and measurements of myeloperoxidase activity and of plasma exudation into the colonic segment. The experimental colitis showed morphological similarities to human ulcerative colitis, with 3-fold increase in myeloperoxidase activity and 6-fold increase in the plasma exudation. Budesonide in different doses administered for 3 days, starting one day after acetic acid instillation, prevented the development of colitis in a dose-dependent manner. The best effect of budesonide on the morphological score was achieved after local treatment at a dose of 10(-5) M twice daily (76% reduction compared with a control colitis group) and parenteral treatment with 0.75 mg/kg (80% reduction). These doses also normalized myeloperoxidase activity and significantly reduced the plasma exudation. The systemic effects of the drug were most pronounced in the group treated with parenteral budesonide. This group showed the greatest reduction in body weight and a significant reduction of the weight of adrenal glands and spleen (as compared to controls). Thymus weight in animals treated systemically was significantly lower than in locally treated animals. In the group treated with local budesonide the weight of adrenals was reduced. However, the weights of spleen and thymus were not reduced and the reduction of the body weight was even less than in the control group.. Local treatment with budesonide at a dose of 10(-5) M (0.17 mg/kg if completely absorbed, but only 0.03 mg/kg with 15% bioavailability on colonic application) was as effective as parenteral treatment at a dose of 0.75 mg/kg in the attenuation of acetic acid-induced colitis in the rat, but resulted in minor systemic side-effects. Topics: Acetates; Acetic Acid; Administration, Topical; Animals; Anti-Inflammatory Agents; Body Weight; Budesonide; Colitis; Dose-Response Relationship, Drug; Female; Glucocorticoids; Injections, Subcutaneous; Organ Size; Peroxidase; Pregnenediones; Rats; Rats, Sprague-Dawley | 1994 |
Neutrophil-independence of the initiation of colonic injury. Comparison of results from three models of experimental colitis in the rat.
Although the role of neutrophils in the pathogenesis of several forms of gastrointestinal injury has been well demonstrated, their role in the development of experimental colonic injury is less clear. To examine whether neutrophils play a role in the development of experimental colitides, the effects of a sustained neutropenia on multiple indices of colonic injury in rats was examined 24 hr following the initiation of colitis with the intrarectal application of acetic acid, trinitrobenzene sulfonic acid (TNBS)-ethanol, or the potent proinflammatory agent, phorbol-12-myristate-13-acetate (PMA). In comparison to animals with normal neutrophil counts and colitis induced by any of the three agents, no attenuation in macroscopic damage or histopathologic injury was observed in neutropenic animals exhibiting a greater than 95% reduction in circulating neutrophils and 85% reduction in tissue-associated myeloperoxidase activity. Although the tissue edema associated with acetic acid or PMA-induced colitis was not reduced by neutropenia, the colonic edema associated with TNBS colitis was attenuated by prior neutrophil depletion with anti-neutrophil antiserum. Despite our initial hypothesis that neutrophils played a key role in the genesis of experimental colitis (especially that induced by PMA), the results demonstrated that these cells are not essential for the development of the major pathological features of colitis induced by this agent, acetic acid, or TNBS. Although these results support the proposal that in these models of colitis, inflammation develops secondary to injury (rather than the converse), further studies will be necessary to elucidate the role of inflammatory cells other than neutrophils in the genesis of experimental colitides. Topics: Acetates; Acetic Acid; Animals; Colitis; Colon; Ethanol; Leukocyte Count; Male; Neutropenia; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Tetradecanoylphorbol Acetate; Time Factors; Trinitrobenzenesulfonic Acid | 1994 |
Protective effect of epidermal growth factor in an experimental model of colitis in rats.
The role of epidermal growth factor (EGF) in the maintenance of mucosal integrity in the lower gastrointestinal tract is unknown. The aim of this study was to determine the effect of EGF in experimental colitis.. Colitis was induced with 2,4,6-trinitrobenzenesulfonic acid/ethanol enemas. Rats were pretreated with intraperitoneal administration of recombinant human EGF (600 micrograms/kg) or vehicle 1 hour before induction of colitis and daily thereafter until killed at 8 hours, 48 hours, and 1 week. A separate group received an identical dosage and administration of EGF or vehicle for 1 week with treatment initiated 24 hours after the induction of colitis. Colonic tissue was evaluated macroscopically, histologically, and for myeloperoxidase activity.. Pretreatment with EGF reduced microscopic erosions at 8 and 48 hours by 74% and 54%, respectively (P < 0.05). At 1 week, microscopic ulcerations and myeloperoxidase activity were reduced by 65% in the EGF-pretreated group (P < 0.05). No significant difference in macroscopic injury, histological damage, or myeloperoxidase activity was noted when EGF treatment was initiated after the induction of colitis.. Systemic EGF administration reduces mucosal damage and inflammation in a trinitrobenzenesulfonic acid/ethanol model of colitis in rats through a mechanism involving mucosal protection. Topics: Animals; Colitis; Disease Models, Animal; Epidermal Growth Factor; Ethanol; Gastric Mucosa; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1994 |
Role of cytokine-induced neutrophil chemoattractant, a member of the interleukin-8 family, in rat experimental colitis.
A study was made of the role of cytokine-induced neutrophil chemoattractant (CINC), regarded as a member of the interleukin-8 family, in rat experimental colitis induced by trinitrobenzene sulfonic acid and ethanol. Colonic myeloperoxidase (MPO) activity, a marker of tissue neutrophil infiltration, was observed to reach a plateau from 24 h to 1 week following the induction of colitis; tissue CINC levels, as measured by enzyme-linked immunosorbent assay, rose rapidly, peaking at 12 h before the rise in myeloperoxidase activity. The time-course of tissue leukotriene B4, another chemoattractant, was followed by that of MPO activity. Neutrophil accumulation into tissue in this model would thus appear to be under the control of CINC. Anti-CINC was also noted to inhibit 32.9 to 58.1% of chemotactic activity determined by bioassay during the same period, this being further evidence that CINC is a major chemotactic agent in this model. The present results indicate that CINC may have a crucial role in initiating neutrophil infiltration in experimental colitis. Topics: Animals; Chemokines, CXC; Chemotactic Factors; Colitis; Colon; Enzyme-Linked Immunosorbent Assay; Ethanol; Growth Substances; Intercellular Signaling Peptides and Proteins; Interleukin-8; Leukotriene B4; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1994 |
Beneficial effects of local or systemic lidocaine in experimental colitis.
Neuropeptides liberated from enteric neurons have been suggested to contribute to the inflammatory process in colitis. Based in part on this evidence, lidocaine enemas have recently been suggested as a treatment for ulcerative colitis, but their effects have yet to be fully characterized. We have assessed the effects of lidocaine on the development and maintenance of colitis induced by trinitrobenzenesulfonic acid (TNBS) in rats. In the initial experiments, rats were given lidocaine [5-100 mg/kg intrarectally] 30 min before TNBS administration, and the severity of colitis was assessed 6-24 h later. In subsequent experiments, rats received lidocaine intrarectally or subcutaneously 30 min before TNBS administration and once daily for 7 days. The severity of colitis was assessed by blind macroscopic scoring, measurement of myeloperoxidase activity, and histological evaluation. Lidocaine dose dependently reduced the severity of colitis and the infiltration of granulocytes at 24 h and 7 days post-TNBS. At the latter time point, lidocaine was also found to improve the histological appearance of the tissue and significantly reduce mucosal mast cell hyperplasia. Beneficial effects were also evident when intrarectal lidocaine treatment was initiated after induction of colitis or when lidocaine was given subcutaneously. Granulocyte infiltration into the colon could also be attenuated by a substance P receptor antagonist. These results suggest that lidocaine can exert anti-inflammatory effects in colitis, perhaps by virtue of its effects on intrinsic and/or extrinsic nerves. Topics: Administration, Rectal; Animals; Cell Count; Chemotaxis; Colitis; Colon; Dose-Response Relationship, Drug; Granulocytes; Injections, Subcutaneous; Lidocaine; Male; Mast Cells; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid; Weight Gain | 1994 |
Central interleukin-1 receptors contribute to suppression of feeding after acute colitis in the rat.
Experimental colitis, induced in rats by intrarectal administration of trinitrobenzenesulfonic acid (TNB), results in a suppression of eating for 3 days. Because interleukin-1 (IL-1) is elevated within 24 h after TNB treatment, and because chronic administration of IL-1 leads to a pattern of anorexia similar to that seen after TNB, we evaluated the role of endogenous IL-1 in the anorexia observed in the TNB model. Human recombinant IL-1 receptor antagonist (rhIL-1ra) was administered chronically via osmotic minipump either peripherally or centrally after TNB treatment. Peripheral delivery of 40 micrograms/h rhIL-1ra significantly attenuated TNB-induced anorexia. However, 24 micrograms/h rhIL-1ra attenuated TNB-induced anorexia only when delivered centrally, not peripherally. These findings implicate central IL-1 receptors in the suppression of eating during acute experimental colitis but leave open a possible involvement of peripheral IL-1 receptors. Topics: Animals; Body Weight; Colitis; Ethanol; Feeding Behavior; Humans; Inflammation; Interleukin-1; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Interleukin-1; Recombinant Proteins; Time Factors; Trinitrobenzenesulfonic Acid | 1994 |
Mucosal injury and inflammation in a model of chronic granulomatous colitis in rats.
The objective of this study was to characterize the acute and chronic inflammation induced by the intramural injection of peptidoglycan-polysaccharide (PG-PS) into the distal colon of genetically susceptible rats.. Blood-to-lumen clearance of 51Cr-ethylenediaminetetraacetic acid, colonic myeloperoxidase activity, colon weight, and plasma nitrite and nitrate levels were determined to quantitate colonic mucosal injury, inflammation, and nitric oxide (NO) production, respectively.. Intramural injection of PG-PS into the distal colon produced a local biphasic inflammatory response composed of an acute episode 3 days after injection; this was followed by a spontaneous reactivation of chronic granulomatous colitis manifested by colonic thickening, adhesions, and infiltration of the submucosa and muscularis propria with macrophages, neutrophils, and lymphocytes at 3-4 weeks. Mucosal ulcers were evident only at 3 weeks, but hepatic nodules, splenic necrosis, and arthritis were evident at both 3 and 4 weeks after PG-PS injection. PG-PS produced significant increases in colonic mucosal permeability, myeloperoxidase activity, and plasma nitrite and nitrate levels at 3 weeks postinjection compared with controls. PG-PS stimulated the production of nitrite by elicited peritoneal macrophages and neutrophils in vitro.. PG-PS produces a chronic granulomatous colitis in rats; this colitis is characterized by enhanced NO production. Topics: Amino Acid Oxidoreductases; Animals; Chronic Disease; Colitis; Crohn Disease; Disease Models, Animal; Enzyme Induction; Female; Granuloma; Intestinal Mucosa; Nitric Oxide Synthase; Peptidoglycan; Peroxidase; Rats; Rats, Inbred Lew; Streptococcus pyogenes | 1993 |
Attenuation of epithelial injury in acute experimental colitis by immunomodulators.
Intestinal epithelial permeability can be modulated by the immune system and can be greatly increased by transepithelial migration of neutrophils. Since immunosuppressants have been reported to inhibit the ability of neutrophils to migrate, we assessed the effects of two immunosuppressants on epithelial permeability and granulocyte infiltration in a model of acute colitis. Epithelial permeability was measured at 3 and 6 h after induction of colitis in the rabbit by intracolonic administration of trinitrobenzene sulfonic acid. At these times, blood-to-lumen leakage of 51Cr-EDTA was elevated by approximately 8- and 18-fold, respectively, above levels observed in healthy controls. Pretreatment with either of the immunosuppressants (cyclosporin A and L-683,590) significantly reduced the changes in 51Cr-EDTA leakage observed at the latter time point. These drugs also significantly attenuated granulocyte infiltration of the colon after induction of colitis, as measured by tissue myeloperoxidase activity. Unlike the immunosuppressants, misoprostol, a prostaglandin analogue, attenuated the increases in colonic permeability but had no effect on granulocyte infiltration in this model. These results demonstrate that two structurally unrelated immunosuppressants are capable of markedly reducing neutrophil infiltration and the colonic permeability changes observed in an experimental model of acute colitis, although the mechanisms through which these effects are produced remain unclear. Topics: Animals; Colitis; Colon; Cyclosporine; Disease Models, Animal; Epithelium; Immunosuppressive Agents; Male; Misoprostol; Neutrophils; Permeability; Peroxidase; Rabbits; Tacrolimus; Trinitrobenzenesulfonic Acid | 1993 |
Effects of zileuton, a new 5-lipoxygenase inhibitor, in experimentally induced colitis in rats.
The efficacy of zileuton, a new 5-lipoxygenase inhibitor, was investigated in comparison with sulphasalazine in an experimental model of rat colitis. Under light anaesthesia with ether, male rats were subjected to intracolonic administration of trinitrobenzene sulfonic acid (TNB) in 50% ethanol and were then sacrificed 2, 4 and 7 days after colitis induction. Untreated rats exhibited elevated colonic levels of leukotriene B4 (LTB4) and 6-keto-PGF1 alpha, and an increase in colonic myeloperoxidase (MPO) activity (investigated as an index of leukocyte adhesion and accumulation). Moreover, ulceration and inflammation of the distal colon with formation of granuloma and pathologic connections were observed. Treated rats received zileuton or sulphasalazine (50 mg/kg per os twice a day) 24 h before the induction of colitis until they were sacrificed. Treatment with the specific 5-lipoxygenase inhibitor, zileuton, resulted in significant reductions of colonic leukotriene B4 and 6-keto-PGF1 alpha synthesis, macroscopic and histological colonic damage and colonic inflammation as assessed by the measurement of MPO activity. In contrast, sulphasalazine had a lower effect than zileuton on LTB4 and MPO levels (p < 0.05), while it was able to reduce colonic damage and 6-keto-PGF1 alpha levels as well as zileuton. This study shows, therefore, that zileuton is effective in attenuating the lesions in an experimental model of colitis. Furthermore, the results are consistent with the hypothesis that leukotrienes play an important role in the pathogenesis of intestinal bowel diseases (IBD). Topics: Animals; Colitis; Colon; Eicosanoids; Hydroxyurea; Inflammatory Bowel Diseases; Leukocytes; Lipoxygenase Inhibitors; Male; Peroxidase; Rats; Rats, Wistar; Sulfasalazine; Trinitrobenzenesulfonic Acid | 1993 |
Effect of a new de-N-acetyl-lysoglycosphingolipid on chemically-induced inflammatory bowel disease: possible mechanism of action.
A new, orally active de-N-acetylated lysoglycosphingolipid (WILD20) was evaluated as antiinflammatory agent using a model of chemically-induced inflammatory bowel disease (IBD) in the rat to mimic human ulcerative colitis and Chron's disease. IBD was induced by hapten trinitrobenzenesulphonic acid (TNB). WILD20, orally administered as preventive or curative, was demonstrated to be efficacious at daily dosages of 0.1-1 mg/kg for 4-5 days. Damage scores, body weight, spleen weight, colonic tissular levels of LTB4, myeloperoxidase (MPO) and malondialdehyde (MDA) are influenced and brought into parameters of normality. Histological observation demonstrated quicker healing, better repair, reduced inflammation, and poor eosinophil degranulation. The mechanisms underlying WILD20 antiinflammatory effects were investigated: whereas WILD20 fails to show a direct effect on PKC, it reduces PKC translocation to the membrane; cellular PLA2 was consequently greatly reduced through this mechanism and thought to be responsible for WILD20 efficacy towards chemically-induced IBD. Topics: Animals; Arachidonic Acid; Carbohydrate Sequence; Colitis; Colon; Gangliosides; Humans; Inflammatory Bowel Diseases; Leukotriene B4; Male; Malondialdehyde; Molecular Sequence Data; Organ Size; Pancreas; Peroxidase; Phospholipases A; Phospholipases A2; Platelet Activating Factor; Platelet Aggregation Inhibitors; Rats; Rats, Wistar; Spleen; Synovial Fluid; Trinitrobenzenesulfonic Acid | 1993 |
Characterization of suppression of food intake following acute colon inflammation in the rat.
Experimental colitis was induced in rats by intrarectal infusion of trinitrobenzenesulfonic acid and ethanol. Colitis was accompanied by a large suppression of food intake of 3 days duration. The reduction of food intake was effected through a reduction of meal size, with no change in meal frequency. Those same rats demonstrating approximately 70%-80% suppression of daily food intake showed no reduction of sham feeding. These data indicate that malaise alone is inadequate to explain the suppression of food intake associated with acute colitis. Rather, the data suggest that the suppression of eating results from an exaggerated postprandial satiety signal elaborated during the period of acute inflammation, an interpretation consistent with the demonstration of a slowed rate of gastric emptying in association with the colitis. Topics: Analysis of Variance; Animals; Appetite; Biomarkers; Colitis; Colon; Ethanol; Feeding Behavior; Gastric Emptying; Inflammation; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Time Factors; Trinitrobenzenesulfonic Acid | 1993 |
Impairment of bacterial flora in human ulcerative colitis and experimental colitis in the rat.
Changes in the colonic mucosa-associated microflora were determined both in patients with active and inactive ulcerative colitis and in rats with acetic acid-induced colitis. In patients with active ulcerative colitis, significant decreases in the number of anaerobic bacteria (Brain Heart Infusion medium), anaerobic gram-negatives and Lactobacillus were found, whereas no changes were seen in the number of aerobic bacteria and Enterobacteriaceae. In patients with inactive ulcerative colitis, no significant differences in colonic mucosa-associated microflora could be demonstrated. Similar changes were seen in rats with acetic acid-induced colitis. Thus, 4 days after acetic acid administration, at which time the colitis was well developed as evaluated by morphological appearance and myeloperoxidase activity, reduction in the number of anaerobic bacteria and Lactobacillus was seen. The first day after acetic acid administration, when the colitis had not developed, or after 14 days, when the colitis had been overcome, no alterations were seen in the mucosa-associated microflora as compared with control rats. We conclude that a reduction in the number of anaerobic bacteria and Lactobacillus is a common feature in active colitis regardless of the origin of colitis. Topics: Acetates; Acetic Acid; Animals; Bacteria, Anaerobic; Colitis; Colitis, Ulcerative; Colon; Enterobacteriaceae; Female; Humans; Intestinal Mucosa; Lactobacillus; Male; Middle Aged; Peroxidase; Rats; Rats, Sprague-Dawley; Time Factors | 1993 |
The leukocyte recruitment inhibitor, NPC 15669 accelerates healing in acetic acid-induced colitis.
The therapeutic efficacy of the leukocyte recruitment inhibitor, NPC 15669 (N-[9H-(2,7-dimethylfluoren-9-yl-methoxy)carbonyl]-L-leucine), was evaluated through the time course of acetic acid colitis in rats. Intrarectal (i.r.) administration of dilute acetic acid produced intense inflammation of the colon, neutrophil infiltration, hemorrhage, necrosis and denuding of epithelium. Myeloperoxidase (MPO) accumulation increased approximately 40-fold (by day 1) and significant resolution of the disease occurred by day 9. When NPC 15669 (10 mg/kg, i.r.) was administered 24 h after acid, MPO accumulation and colonic lesion scores were significantly inhibited (days 3-9) and histological examination revealed the absence of hemorrhage, epithelial cell regeneration and complete restoration of the mucosal architecture. Thus, NPC 15669 prevents colonic damage and promotes healing of ulcers, even when administered at the peak of the inflammatory response. Topics: Acetates; Acetic Acid; Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Disease Models, Animal; Intestinal Mucosa; Leucine; Male; Peroxidase; Rats; Rats, Sprague-Dawley | 1993 |
Effect of epidermal growth factor on experimental colitis in the rat.
The effect of epidermal growth factor on the rate of healing was examined in a rat model of colitis. Ulceration and inflammation of the distal colon were induced by a single intracolonic administration of 0.25 ml of 30% ethanol containing 30 mg of trinitrobenzenesulfonic acid. Epidermal growth factor was delivered intracolonically via the rectum or s.c. for 7 days after induction of colitis. Repeated s.c. injections of epidermal growth factor (25 and 100 micrograms/kg/12 hr) or continuous s.c. delivery with Alzet osmotic pumps (50 and 200 micrograms/kg/24 hr) significantly reduced colonic ulceration and inflammation. Epidermal growth factor significantly reduced myeloperoxidase activity in colonic tissue and there was restitution of the glandular mucosa after epidermal growth factor treatment. In contrast, daily intracolonic treatment with epidermal growth factor (25, 100 and 200 micrograms/kg/24 hr) did not significantly reduce the colonic damage. However, intracolonic delivery of 5-aminosalicylic acid (100 and 200 mg/kg/24 hr) dose-dependently reduced the colonic damage as assessed macroscopically and histologically. We conclude that systemic and not intracolonic administration of epidermal growth factor can accelerate healing of colonic ulceration and is effective in reducing inflammation in this model of colitis. Topics: Aminosalicylic Acids; Animals; Colitis; Colon; Disease Models, Animal; Eicosanoids; Epidermal Growth Factor; Ethanol; Intestinal Mucosa; Male; Mesalamine; Peroxidase; Prednisolone; Rats; Rats, Sprague-Dawley; Trinitrobenzenesulfonic Acid | 1993 |
The effect of exogenous administration of Lactobacillus reuteri R2LC and oat fiber on acetic acid-induced colitis in the rat.
The potential beneficial effect of exogenous administration of Lactobacillus on acetic acid-induced colitis was evaluated in the rat. Colitis was induced by instillation of 4% acetic acid for 15 sec in an exteriorized colonic segment. This produced uniform colitis with a threefold increase in myeloperoxidase (MPO) activity of the colonic tissue (an index of neutrophil infiltration) and a sixfold increase in plasma exudation into the lumen of the colon (mucosal permeability) as evaluated 4 days after acetic acid administration. Intracolonic administration of L. reuteri R2LC immediately after acetic acid administration, at a dose of 5 ml of 7 x 10(7) colony-forming units (CFU)/ml in two forms: either as pure bacterial suspension or as fermented oatmeal soup, prevented the development of colitis. Thus, the morphologic score, MPO activity, and mucosal permeability were almost normalized by Lactobacillus treatment. Initiating the treatment 24 h after acetic acid administration or using lower doses of 1 ml for 3 consecutive days resulted in a smaller protective effect. We conclude that exogenous administration of L. reuteri R2LC prevents the development of acetic acid-induced colitis in the rat. Topics: Acetates; Animals; Colitis; Dietary Fiber; Disease Models, Animal; Edible Grain; Female; Intestinal Mucosa; Lactobacillus; Permeability; Peroxidase; Rats; Rats, Sprague-Dawley; Species Specificity | 1993 |
NPC 15669, an inhibitor of neutrophil recruitment, is efficacious in acetic acid-induced colitis in rats.
The efficacy of the leukocyte recruitment inhibitor, N-[9H-2,7-dimethylfluoren-9-ylmethoxy)carbonyl]-L-leucine (NPC 15669) was compared with drugs used to treat inflammatory bowel diseases in a rat model, acetic acid-induced colitis.. Colonic damage assessed by visual inspection, histological quantitation of tissue injury, vascular permeability, myeloperoxidase (MPO) accumulation, and synthesis of inflammatory mediators were measured.. Intrarectal pretreatment with NPC 15669 results in a significant reduction of all measured indices of inflammation. The median effective dose (ED50) of NPC 15669 for inhibition of MPO accumulation and vascular permeability is 13.2 mg/kg and 31 mg/kg, respectively. The active moiety of sulfasalazine, 5-aminosalicylic acid (5-ASA), the antioxidant/5-lipoxygenase inhibitor, nordihydroguaiaretic acid (NDGA) and the corticosteroids dexamethasone and hydrocortisone, yielded ED50 values (MPO accumulation) of 68 mg/kg, 95 mg/kg, 0.7 mg/kg, and 13 mg/kg, respectively. When formulated suspensions of NPC 15669, 5-ASA, or dexamethasone were used, potency was increased 10-40-fold. Furthermore, NPC 15669 (10 mg/kg) administered 7 hours after acetic acid and evaluated 24 hours after acetic acid administration significantly attenuated neutrophil influx (70% inhibition of MPO accumulation), whereas 5-ASA (100 mg/kg) displayed no therapeutic effects.. NPC 15669 may be useful in the treatment of inflammatory disorders. Topics: Acetates; Acetic Acid; Aminosalicylic Acids; Animals; Anti-Inflammatory Agents, Non-Steroidal; Capillary Permeability; Colitis; Colon; Dexamethasone; Fluorenes; Glycine; Hydrocortisone; Leucine; Leukotriene B4; Male; Masoprocol; Mesalamine; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Thromboxane B2 | 1993 |
Acetic acid-induced colitis results in bystander ileal injury.
The extent of the small intestinal injury following experimental acetic acid induction of colitis in rats was examined. Following intraluminal colonic administration of radiolabelled acetic acid, high levels of radioactivity were identified in the colon and in the liver, while low background levels were found in jejunum, ileum, caecum, and heart. The increased level of radioactivity in the liver relative to that of the heart suggests that a significant portion of the colonic intraluminal acetic acid was absorbed directly into the portal circulation. The colon, which was the only segment of intestine in direct contact with the acetic acid, had the highest levels of radiolabelled acetic acid, demonstrated a marked macroscopic mucosal ulceration, an enhanced myeloperoxidase activity, and a fall in in vivo fluid absorption. The jejunum, which demonstrated low levels of radiolabelled acetic acid was normal without evidence of injury. In contrast, the ileum, which displayed the same levels of radiolabelled acetic acid as did the jejunum, also demonstrated a significant fall in in vivo fluid absorption but showed no mucosal ulceration or increased myeloperoxidase activity. These studies have shown that acetic acid induction of colitis produces evidence of ileal injury but that this injury is not the result of inadvertent delivery of acetic acid or recruitment of neutrophils to the ileal mucosa. Topics: Acetates; Acetic Acid; Animals; Body Fluids; Cecum; Colitis; Colon; Disease Models, Animal; Ileum; Injections, Intraperitoneal; Intestinal Mucosa; Intestine, Small; Jejunum; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Tissue Distribution | 1993 |
Effect of growth hormone on the inflammatory activity of experimental colitis in rats.
The effect of daily treatment with 2.0 mg biosynthetic human growth hormone per kilogram body weight or isotonic NaCl (controls) on experimental colitis was investigated in rats. Colonic inflammation was induced by instillation of trinitrobenzene sulfonic acid (TNB) intraluminally into the left colon. Untreated NaCl-instilled rats were used for comparison with intact colon. Four days after TNB instillation the growth hormone-treated rats had lower macroscopic and microscopic damage scores and less infiltration of neutrophils, measured as myeloperoxidase activity (MPO), than controls. The biomechanical properties of the colon showed that the breaking strength and energy absorption were reduced in the control rats with colitis compared with intact colon, whereas the rats treated with growth hormone had unchanged strength and energy absorption. The differences in MPO activity, damage scores, and biomechanical properties were associated with a higher concentration of insulin-like growth factor I in serum from growth hormone-treated rats after 4 days than controls. Finally, the growth hormone-treated rats regained their initial body weight after 7 days, in contrast to the body weight of control rats, which remained 11% lower than their initial body weight. Topics: Animals; Biomechanical Phenomena; Colitis; Colon; Growth Hormone; Humans; Insulin-Like Growth Factor I; Male; Peroxidase; Rats; Rats, Wistar; Recombinant Proteins; Trinitrobenzenesulfonic Acid | 1993 |
Effect of putative phospholipase A2 inhibitors on acetic acid-induced acute colitis in the rat.
Phospholipase activation may play an important role in ulcerative colitis. This hypothesis was tested by evaluating the effect of two non-selective phospholipase (PL) A2 inhibitors, quinacrine and p-bromophenacyl-bromide (pBPB), on acetic acid-induced colitis in the rat. The calcium antagonist verapamil, which may also act as a PLA2 inhibitor, was also tested. Acute colitis was induced in an isolated colonic segment by instillation of 4 per cent acetic acid for 15 s; this induces a uniform colitis after 4 days. The severity of colitis was evaluated histologically, by measuring myeloperoxidase (MPO) activity and by determining plasma exudation into the lumen of the colon (permeability) with 125I-labelled albumin given intravenously. All three putative PLA2 inhibitors tested were found to prevent the development of colitis. Intravenous administration of quinacrine 10 mg kg-1 at 30 min before instillation of acetic acid resulted in a normal mucosal appearance, normal MPO activity and a significantly reduced increase in plasma exudation into the colon. A similar effect was achieved using verapamil. Intracolonic administration of either quinacrine or pBPB also prevented acetic acid-induced colitis. However, three doses, starting immediately after acetic acid administration and repeated on the first and second days, were needed to achieve this, whereas one dose produced only a partial effect. PLA2 may play an important role in acetic acid-induced colitis and inhibition of its activity may offer an alternative mode of treatment in ulcerative colitis. Topics: Acetates; Acetic Acid; Acetophenones; Animals; Colitis; Colon; Enzyme Activation; Female; Intestinal Mucosa; Peroxidase; Phospholipases A; Phospholipases A2; Quinacrine; Rats; Rats, Sprague-Dawley; Verapamil | 1993 |
Exacerbation of experimental colitis by nonsteroidal anti-inflammatory drugs is not related to elevated leukotriene B4 synthesis.
The ability of nonsteroidal anti-inflammatory drugs to exacerbate experimental colitis, and the possible contributions of the "shunting" of arachidonate via the 5-lipoxygenase pathway, were investigated using a rat model in which colitis was induced by intracolonic administration of trinitrobenzene sulfonic acid in a vehicle of 50% ethanol. Twice daily treatment with indomethacin (0.1-1 mg/kg SC) during the first week after trinitrobenzene sulfonic acid/ethanol administration resulted in dose-dependent increases in the severity of colitis and in the incidence of mortality. Mortality was not observed in vehicle-treated colitic rats or in normal rats treated with indomethacin. Similar exacerbation of colitis was observed in rats treated with naproxen (5 mg/kg). Whereas treatment with a 5-lipoxygenase inhibitor, PF-5901 (100 mg/kg PO), resulted in a significant reduction of the severity of colitis, concomitant administration of PF-5901 and indomethacin (0.5 mg/kg SC) did not inhibit the exacerbative effects of the indomethacin in this model. In separate studies, administration of indomethacin was found to significantly increase colonic myeloperoxidase activity (a measure of tissue granulocyte numbers) and suppress colonic prostaglandin E2 synthesis, while not significantly affecting colonic leukotriene B4 synthesis. The effect on myeloperoxidase activity was seen during the period 21-24 hours after trinitrobenzene sulfonic acid ethanol administration, but not during the period 45-48 hours after induction of colitis. In in vitro studies using samples of inflamed colon and in vivo studies in which colonic eicosanoid production was measured by colonic dialysis, inhibition of prostaglandin E2 synthesis was not accompanied by significant changes in leukotriene B4 synthesis. These results suggest that inhibitors of colonic prostaglandin synthesis can markedly exacerbate colitis, and that this effect is unrelated to alterations in colonic leukotriene B4 synthesis. Endogenous prostaglandins may exert anti-inflammatory effects during the acute stages of colitis. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Colitis; Colon; Dinoprostone; Drug Combinations; Indomethacin; Leukotriene B4; Male; Misoprostol; Naproxen; Peroxidase; Quinolines; Rats; Rats, Inbred Strains | 1992 |
Verapamil alters eicosanoid synthesis and accelerates healing during experimental colitis in rats.
In inflammatory bowel disease, prostaglandins are mucosal protective whereas leukotrienes are proinflammatory. Recent evidence suggests that the formation and action of leukotrienes are calcium-dependent, whereas the formation and action of prostaglandins are not. To examine the possibility that, because of differential regulation of arachidonic acid metabolism, calcium channel blockade might alter mucosal eicosanoid synthesis and accelerate healing during inflammatory bowel disease, we treated a 4% acetic acid-induced colitis model with verapamil and/or misoprostol and determined the effects on colonic macroscopic injury, mucosal inflammation as measured by myeloperoxidase activity, in vivo intestinal fluid absorption, and mucosal prostaglandin E2 and leukotriene B4 (LTB4) levels as measured by in vivo rectal dialysis. In colitic animals, verapamil treatment significantly improved colonic fluid absorption and macroscopic ulceration. This mucosal-protective effect of verapamil occurred in the presence of a twofold reduction in mucosal LTB4 synthesis. In noncolitic animals, verapamil alone had no effect on in vivo fluid absorption, macroscopic ulceration, or myeloperoxidase activity but did induce a threefold reduction in LTB4 synthesis in addition to shifting arachidonic acid metabolism towards a sixfold stimulation of prostaglandin E2 synthesis. Our results show that, when administered before the experimental induction of colitis, the calcium channel blocker, verapamil, has a mucosal-protective effect that occurs as a consequence of reduced mucosal leukotriene synthesis and increased prostaglandin synthesis. This differential regulation of arachidonic acid metabolism may play an important role in the development of novel therapeutic agents for inflammatory bowel disease. Topics: Animals; Colitis; Colon; Dinoprostone; Intestinal Absorption; Leukotriene B4; Male; Peroxidase; Rats; Rats, Inbred Strains; Verapamil | 1992 |
A comparative analysis of two models of colitis in rats.
Two models of colitis produced in rats that have received significant attention over the past few years are the acetic acid and trinitrobenzene sulfonic acid (TNBS) models. The objective of this study was to quantify and compare the temporal relationship among mucosal permeability, epithelial injury, and inflammation induced by acetic acid, ethanol (vehicle), ethanol plus TNBS (unbuffered, pH 1.0), and ethanol plus TNBS (pH 7.4). Data obtained show that the inflammation induced by these four irritants results from caustic injury to the colonic epithelium and interstitium as measured by the rapid and dramatic increases in mucosal permeability and tissue water content as well as by histological analysis. The injurious nature of TNBS was confirmed in a separate series of studies showing that buffered TNBS (pH 7.4), in the absence of ethanol, is toxic to cultured rat intestinal epithelial cell monolayers. Only after 1-2 days of the initial insult, were signs of classical inflammation observed, including increases in colonic myeloperoxidase activity (neutrophil infiltration) and colon weight as well as hyperemia and mucosal ulcerations. Although ethanol plus TNBS (pH 1.0 or 7.4) tended to produce higher mucosal permeabilities (epithelial cell injury) at 1-2 weeks after the enemas than acetic acid or ethanol groups, only the ethanol plus TNBS (pH 7.4) permeabilities were found to be significantly enhanced. In addition, all four groups showed significant elevations in colonic myeloperoxidase activity and colon weight at 1-2 weeks after enema. It is suggested that these models of colitis are useful to study events that occur at the time of inflammation and repair. However, these models may have significant limitations in understanding events that initiate inflammation of the intestine in human inflammatory bowel disease. Topics: Acetates; Acetic Acid; Animals; Colitis; Colon; Disease Models, Animal; Ethanol; Intestinal Mucosa; Male; Peroxidase; Rats; Rats, Inbred Strains; Trinitrobenzenesulfonic Acid | 1992 |
Prevention and reversal of experimental colitis by a monoclonal antibody which inhibits leukocyte adherence.
The role of neutrophils in the pathogenesis of acute colitis was investigated using a rabbit model. Colitis was induced by intracolonic administration of trinitrobenzene sulfonic acid in 30% ethanol. Myeloperoxidase activity was measured at various times after induction of colitis as an index of neutrophil infiltration, and this was confirmed by histology. The permeability of the colonic epithelium to [51Cr]EDTA was also measured at various times after induction of colitis. The most marked increase in neutrophil infiltration of the colon occurred during the period 3-6 h after induction of colitis. This was also the period in which the greatest increase in colonic permeability was observed. Pretreatment with a monoclonal antibody (IB-4) directed against the leukocyte adhesion molecule, CD18, markedly suppressed neutrophil infiltration into the colonic tissue after induction of colitis. This pretreatment also significantly reduced the extent of epithelial injury. Administration of IB-4 to rabbits 12 h after induction of colitis resulted in a rapid decline in tissue myeloperoxidase activity. When measured 12 h after IB-4 administration (3 mg/kg), colonic myeloperoxidase activity was reduced by about 80% compared to the control group treated with the vehicle. These results are consistent with the hypothesis that neutrophils contribute significantly to the epithelial dysfunction that characterizes colitis and suggest that antibodies directed against adhesion molecules may represent a novel approach to the treatment of intestinal inflammatory disorders. Topics: Acute Disease; Animals; Antibodies, Monoclonal; Antigens, CD; Cell Adhesion; Colitis; Epithelium; Neutrophils; Permeability; Peroxidase; Rabbits; Trinitrobenzenesulfonic Acid | 1992 |
Indomethacin worsens and a leukotriene biosynthesis inhibitor accelerates mucosal healing in rat colitis.
The implication of leukotrienes as mediators of inflammation and recent evidence that prostaglandin analogues provide a beneficial effect during experimental colitis led to the speculation that (i) leukotrienes may be injurious and (ii) prostaglandins may be protective to colonic mucosa. Using a 2% acetic acid induced rat colitis model, we administered specific cyclooxygenase (indomethacin) and leukotriene biosynthesis inhibitors (MK-886) to examine the effect of endogenous prostaglandins and leukotrienes on colonic macroscopic injury, mucosal inflammation as measured by myeloperoxidase activity, net in vivo intestinal fluid absorption, and colonic PGE2 and LTB4 levels as measured by in vivo rectal dialysis. Indomethacin treatment prior to induction of colitis reduced endogenous mucosal PGE2 levels and exacerbated macroscopic ulceration and net fluid absorption. Addition of the exogenous PGE1 analogue misoprostol to the indomethacin-exacerbated colitis completely healed colonic macroscopic ulceration and inflammation but only partially improved fluid absorptive injury. The specific leukotriene biosynthesis inhibitor MK-886 administered prior to induction of colitis healed macroscopic ulceration and inflammation but not fluid absorptive injury. This mucosal reparative effect of MK-886 occurred at a dose that reduced colonic LTB4 synthesis while concomitantly enhancing PGE2 levels. Combining MK-886 with misoprostol treatment improved not only macroscopic ulceration and inflammation but also provided a synergistic effect that maintained net colonic fluid absorption at noncolitic control levels. These studies suggest that, during the induction of experimental colitis, endogenous prostaglandins play a pivotal role in providing a mucosal healing effect, and that leukotriene biosynthesis inhibitor may manifest part of its beneficial effect by shifting arachidonic acid metabolism towards production of prostaglandins. Topics: Acetates; Animals; Body Fluids; Colitis; Dialysis; Dinoprostone; Indoles; Indomethacin; Intestinal Mucosa; Leukotriene Antagonists; Leukotriene B4; Male; Misoprostol; Peroxidase; Rats; Rats, Sprague-Dawley | 1992 |
Inhibition of butyric acid-induced colitis in mice by 16,16-dimethyl prostaglandin E2.
A standard colitic lesion was induced in male BKA mice by intrarectal administration of butyric acid (7.5%, 0.1 ml, 10 sec contact). Animals were killed after 5 h and the 'colitic score', increase in colonic tissue water ('oedema') and colonic tissue content of myeloperoxidase (MPO, a marker for neutrophils) were determined. Drug was administered intrarectally in 0.2 ml saline 20 min before colitis induction. In colitic animals given vehicle alone, all these parameters increased (P less than 0.05) compared to the non-colitic controls. In colitic animals given 16,16-dimethyl PGE2 (0.2-20000 micrograms/kg), colitic score was reduced (P less than 0.05) at all dose levels when compared with vehicle-treated colitic animals. The oedema and MPO showed a dose-related reduction (r = -0.895 and -0.904 respectively). In mouse colon 16,16-dimethyl PGE2 showed a protective action against butyric acid-induced colitic damage. Topics: 16,16-Dimethylprostaglandin E2; Animals; Butyrates; Butyric Acid; Colitis; Colon; Dose-Response Relationship, Drug; Intestinal Mucosa; Male; Mice; Peroxidase | 1992 |
Mucosal protective activity of prostaglandin analogs in rodent colonic inflammation.
The mucosal protective prostaglandin analogs misoprostol, enisoprost, and SC-46275 (the 17E-18-cyclopentenyl analog of enisoprost) were tested in mouse and rat colitis induced by the intrarectal instillation of dilute acetic acid. Colitis was assessed by histology and colonic levels of myeloperoxidase (a neutrophil marker enzyme). When given as enemas 30 min ahead of colitis induction, 15(R)-15-methyl-PGE2 (arbaprostil) and 15(S)-15-methyl-PGE1 were inactive; however, misoprostol, enisoprost, and SC-46275 protected against colonic inflammation with ED50 values of 24, 12 and 1.3 micrograms/kg, respectively, in rats and 11, 5, and 1 micrograms/kg, respectively, in mice. These compounds may have utility in the medical management of human inflammatory bowel disease. Topics: Acetates; Acetic Acid; Animals; Anti-Ulcer Agents; Colitis; Disease Models, Animal; Intestinal Mucosa; Male; Molecular Structure; Peroxidase; Prostaglandins, Synthetic; Rats; Rats, Sprague-Dawley | 1992 |
Granulocyte infiltration in experimental colitis in the rat is interleukin-1 dependent and leukotriene independent.
Intracolonic administration of trinitrobenzene sulfonic acid in ethanol results in the development of colitis in the rat. Previous studies have demonstrated that the severity of this colitis can be markedly reduced by repeated treatment with inhibitors of leukotriene synthesis, although such treatment does not appear to affect the initial migration of granulocytes into the colon. The present study evaluated the contribution of leukotrienes and interleukin-1 to the recruitment of granulocytes into the colon during the first 12 h after induction of colitis. Rats were treated with a leukotriene synthesis inhibitor (PF-5901), a leukotriene B4 receptor antagonist (SC-41930), an IL-1 receptor antagonist or a corticosteroid (prednisolone) prior to induction of colitis. Granulocyte infiltration was assessed by measurement of colonic myeloperoxidase activity and severity of colonic damage was blindly scored. Despite significant inhibition of leukotriene synthesis, PF-5901 did not affect colonic myeloperoxidase activity or the severity of colonic injury at any time point. Similarly, SC-41930 was without significant effect. However, both the interleukin-1 receptor antagonist and prednisolone significantly reduced colonic myeloperoxidase activity (by approximately 50%) and severity of colonic damage at 6 h after induction of colitis, without significantly affecting colonic leukotriene synthesis. These beneficial effects were no longer apparent at 12 h after induction of colitis. This study demonstrates that the infiltration of granulocytes into the colon during the acute phase of colitis in the rat occurs independent of leukotriene synthesis and appears to be at least in part attributable to interleukin-1. Topics: Analysis of Variance; Animals; Benzopyrans; Chemotaxis, Leukocyte; Colitis; Interleukin-1; Kinetics; Leukotriene B4; Male; Neutrophils; Peroxidase; Quinolines; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid | 1992 |
Induction of colitis in rats by 2-2'-azobis(2-amidinopropane) dihydrochloride.
Reactive oxygen metabolites (ROM) may play a role in the pathophysiology of inflammatory bowel disease (IBD) and ischemia-reperfusion-induced intestinal injury. Although there are many reports of intestinal mucosal injury associated with neutrophil-derived ROM, free radicals themselves have not been reported to induce intestinal mucosal injury. We administered intrarectally 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) to rats, an azo compound that generates free radicals in vitro. Acute mucosal injury was assessed histologically by light microscopy and biochemically by myeloperoxidase (MPO) activity. Intrarectal administration of AAPH (60, 90, 150 mg/kg) caused erythema, edema, and histologically verifiable mucosal inflammation. MPO activity was increased 9- to 18-fold above the control level. The levels of thiobarbituric acid (TBA) reactants and sulfhydryls (SH) were significantly (P less than 0.01) increased and decreased, respectively, by 90 mg/kg AAPH. Sulfasalazine, 5-aminosalicylic acid, the LTB4 receptor antagonist SC-41930, and the antioxidant glutathione prevented the inflammation. This model of mucosal inflammation may be useful in evaluating new therapeutic agents for the treatment of IBD. Topics: Amidines; Aminosalicylic Acids; Animals; Benzopyrans; Colitis; Inflammation; Intestinal Mucosa; Lipid Peroxidation; Male; Mesalamine; Oxidation-Reduction; Peroxidase; Rats; Rats, Inbred Strains; Sulfasalazine; Sulfhydryl Compounds; Thiobarbiturates | 1992 |
Inflammatory mediators in cotton-top tamarins (CTT) with acute and chronic colitis.
Spontaneous colitis in CTT's presents cytological characteristics similar to chronic ulcerative colitis in humans, e.g. inflammatory cell infiltrate and crypt abscesses. To better characterize CTT colitis as a potential model for human inflammatory bowel disease (IBD), inflammatory mediators identified in colonic tissue of human IBD patients and/or experimental colitis models were assayed. Inflammatory mediator changes in plasma and colon from tamarins with acute (n = 10) and chronic (n = 10) colitis (by mucosal biopsy) were assayed by RIAs. Similar inflammatory mediators were found in the CTT's with acute colitis. In the plasma, PAF and PGE2 levels were lower in acute colitis CTT's, no LTB4 was detected, and histamine levels were not different from chronic colitic animals. In the colon, myeloperoxidase and interleukin-1 beta were significantly higher in acute colitis, PGE2 and LTB4 were higher but not significantly, and PAF was not different from chronic CTT's. These data suggest that a combination of events are occurring in the pathogenesis of tamarin colitis that involves some of the same mediators that are found in the human disease and in other experimental models. The importance of these findings to human IBD remains for further investigation; however, the spontaneous primate model offers an exciting approximation of the disease development and merits further investigation for understanding the pathogenesis of human IBD as well as to aid in development of targeted therapeutics. Topics: Acute Disease; Animals; Chronic Disease; Colitis; Dinoprostone; Disease Models, Animal; Histamine; Interleukin-1; Leukotriene B4; Peroxidase; Platelet Activating Factor; Saguinus | 1991 |
Azathioprine reduces extravasation and neutrophil trafficking in immune complex-mediated inflammation in the rat colon.
Azathioprine (AZ) has been used in the treatment of refractory inflammatory bowel disease. The mechanism by which AZ decrease colonic inflammation is not known. It is alluded that AZ may be effective in the maintenance of remission. We examined whether AZ in non-immunosuppressive doses reduces extravasation and neutrophil trafficking in a rat model of colonic inflammation. Rats were treated with I.P. injection of AZ (1 mg/kg) for 6 weeks. At the end of 2 and 6 weeks rats were injected I.V. immune complex and on the following day the proximal colon was perfused with 2.5% formaldehyde (local irritant 3 ml/hour for 5 mins). Extravasation was measured by Evans' blue technique and neutrophil concentration in the tissue was determined by measuring myeloperoxidase (MPO). AZ did not inhibit extravasation and MPO after 2 weeks of therapy. However, after 6 weeks, AZ reduced extravasation to 20 +/- 2 micrograms/gm compared to untreated animals (51 +/- 6 micrograms/gm tissue) and MPO levels to 0.3 +/- 13 compared to untreated rats (0.8 +/- 0.32 mU/gm). There was a good correlation between extravasation and MPO levels. These results suggest that long-term treatment with AZ may prevent extravasation and cause reduction in neutrophil trafficking. Such an effect may be beneficial for maintaining remission in IBD. Topics: Aminosalicylic Acids; Animals; Antigen-Antibody Complex; Azathioprine; Colitis; Evans Blue; Male; Mesalamine; Neutrophils; Peroxidase; Rats; Rats, Inbred Strains | 1991 |
Colonic inflammation in the rabbit induced by phorbol-12-myristate-13-acetate.
Neutrophil (PMNL) infiltration of inflamed colonic tissue is a prominent feature of human inflammatory bowel disease (IBD). Colitis was established in New Zealand white rabbits by the intrarectal instillation of 1.5 mg/kg (in 10 ml 20% ethanol) phorbol-12-myristate-13-acetate (PMA) and assessed by visual grading of colonic inflammation, levels of the neutrophil marker enzyme myeloperoxidase (MPO), and histological examination. After 24 h there was a significant (P less than 0.001) increase in MPO levels in the PMA-treated colons compared to ethanol control. There was also increased inflammation based on visual scoring. Histologically, PMA-treated colons were necrotic with focal ulceration, heavy PMNL infiltration and edema at 24 h; by 96 h colitis was sustained with mild edema, crypt abscesses, and a staining pattern suggesting altered mucus quality. These results suggest that PMA-induced colitis in rabbits may be a new model of IBD in which to evaluate drugs known to mitigate the inflammatory process. Topics: Animals; Clinical Enzyme Tests; Colitis; Colon; Disease Models, Animal; Male; Peroxidase; Rabbits; Tetradecanoylphorbol Acetate | 1990 |
Effect of the leukotriene B4 receptor antagonist SC-41930 on colonic inflammation in rat, guinea pig and rabbit.
Inflammatory bowel disease is a chronic inflammatory disorder of the gastrointestinal tract that includes ulcerative colitis and Crohn's disease. Leukotriene B4 is thought to be a prominent proinflammatory mediator in these diseases, in that leukotriene B4 levels are increased in the colonic mucosa of inflammatory bowel disease patients and there is increased polymorphonuclear leukocyte infiltration of these tissues. We evaluated the efficacy of 7-[3-(4-acetyl-3-methoxy-2-propylphenoxy)-3,4-dihydro-8-propyl -2H-1-benzopyran-2-carboxylic acid (SC-41930), a potent, orally active leukotriene B4 receptor antagonist, in a model of inflammatory bowel disease. Colonic mucosal inflammation was induced in rats, guinea pig and rabbits by rectal instillation of a dilute solution of acetic acid. Twenty-four hours later, mucosal levels of myeloperoxidase (a marker enzyme for neutrophil infiltration) and extravasation of i.v. administered Evans blue dye (a marker of vascular disruption and increased permeability) were measured. Tissues were also evaluated histologically. The animals received either SC-41930 or vehicle, intrarectally, 30 min after or 1 hr before and 1 hr after the acetic acid. When given 30 min after acetic acid instillation SC-41930 prevented the rise in myeloperoxidase and dye extravasation observed in the acetic acid inflammed tissue. The SC-41930-treated tissues were less edematous and had fewer neutrophils within the subepithelial space. Median effective dose (ED50) values for vascular protection were approximately 20 mg/kg for both rat and guinea pig. ED50 values for inhibition of granulocyte accumulation were 20 mg/kg for rat, 24 mg/kg for guinea pig and 30 mg/kg for rabbit. These data indicate that SC-41930 is effective locally to prevent acute colonic inflammation. Topics: Animals; Benzopyrans; Capillary Permeability; Colitis; Dose-Response Relationship, Drug; Guinea Pigs; Leukotriene B4; Male; Neutrophils; Peroxidase; Rabbits; Rats; Rats, Inbred Strains; Receptors, Immunologic; Receptors, Leukotriene B4 | 1990 |
Inhibition of leukotriene synthesis markedly accelerates healing in a rat model of inflammatory bowel disease.
The role of leukotrienes in the pathogenesis of chronic colitis was investigated using a rat model. Ulceration and inflammation of the distal colon was initiated by the intracolonic administration of the hapten trinitrobenzene sulfonic acid in 50% ethanol. Leukotriene B4 synthesis increased significantly within 4 h after induction of damage, with the greatest increase observed 24-72 h after administration of the hapten. The increase in leukotriene B4 synthesis correlated well (r = 0.88) with an increase in colonic myeloperoxidase activity, a biochemical marker of neutrophil infiltration. Daily intracolonic treatment with a specific 5-lipoxygenase inhibitor, L651,392, during the first 4 days after initiation of colitis, resulted in significant reductions of colonic leukotriene B4 synthesis, colonic damage score, and colon wet weight. When examined 2 wk after initiation of colitis, the group treated with L651,392 (for the first 4 days) showed significantly less colonic damage (assessed macroscopically and histologically) and colonic inflammation (assessed histologically and by measurement of myeloperoxidase activity). The healing produced by treatment with L651,392 was comparable to that observed after treatment with 5-aminosalicylic acid in a similar manner. Although a reduction of colonic damage could be produced in this model by intracolonic pretreatment with a prostaglandin E1 analogue (rioprostil), the mechanism of action of L651,392 did not appear to be through prevention of the initial injury induced by the hapten and ethanol solution. These results demonstrate that inhibition of leukotriene synthesis results in a marked acceleration of the healing of colonic ulcers and resolution of colonic inflammation in this animal model of chronic colitis. The results are therefore consistent with the hypothesis that leukotrienes play an important role in the pathogenesis of intestinal inflammation. Topics: 6-Ketoprostaglandin F1 alpha; Aminosalicylic Acids; Animals; Chronic Disease; Colitis; Colon; Leukotriene B4; Lipoxygenase Inhibitors; Male; Mesalamine; Peroxidase; Phenothiazines; Prostaglandins E; Rats; Rats, Inbred Strains; Rioprostil | 1989 |
Treatment with 16,16'-dimethyl prostaglandin E2 before and after induction of colitis with trinitrobenzenesulfonic acid in rats decreases inflammation.
Colitis was induced in rats by intrarectal administration of trinitrobenzene sulfonic acid (80 mg/kg, in 30% ethanol). An acute inflammation with ulcers and neutrophil infiltration developed that evolved into a chronic inflammation and luminal narrowing with attendant smooth muscle hypertrophy. We assessed the effects of 16,16-dimethyl prostaglandin E2, administered either before or after trinitrobenzene sulfonic acid, on the development of inflammation. Inflammation was assessed by gross appearance using a grading scale (0-4) and by histology. The number of neutrophils present in inflamed colonic tissue was quantitated by the myeloperoxidase assay. The production of lipoxygenase products was monitored by incubation of colonic specimens with [14C]arachidonic acid and separation of the products by thin-layer chromatography and high-pressure liquid chromatography. Levels of leukotriene B4 were measured in tissue extracts by high-pressure liquid chromatography and ultraviolet absorbance. Eicosanoid production was also assayed by incubating colonic specimens and assaying the media for prostaglandin E2, leukotriene B4, and leukotriene C4 by radioimmunoassay. Trinitrobenzene sulfonic acid treatment resulted in a greatly increased amount of leukotriene B4 in the media. Treatment with 16,16-dimethyl prostaglandin E2 before administration of trinitrobenzene sulfonic acid resulted in a lower inflammation index, lower myeloperoxidase activity, and decreased production of leukotriene B4. Administration of 16,16-dimethyl prostaglandin E2 24 h after administration of trinitrobenzene sulfonic acid was also effective in reducing the inflammatory response. Treatment with 16,16-dimethyl prostaglandin E2 also prevented the development of long-term architectural changes 3 wk after administration of trinitrobenzene sulfonic acid. Rectal administration of dimethyl prostaglandin E2 also diminished the colitis induced by direct injection of trinitrobenzene sulfonic acid into the colonic wall. Topics: 16,16-Dimethylprostaglandin E2; Acute Disease; Animals; Arachidonic Acid; Arachidonic Acids; Colitis; Colon; Dinoprostone; Leukotrienes; Male; Peroxidase; Prostaglandins E, Synthetic; Rats; Rats, Inbred Strains; Trinitrobenzenesulfonic Acid | 1989 |
7-[3-(4-acetyl-3-methoxy-2-propylphenoxy)propoxy]-3,4-dihydro-8- propyl-2H-1-benzopyran-2-carboxylic acid: an orally active selective leukotriene B4 receptor antagonist.
Topics: Animals; Benzopyrans; Chemical Phenomena; Chemistry; Chemotaxis, Leukocyte; Colitis; Cytoplasmic Granules; Guinea Pigs; Humans; Leukotriene B4; Molecular Structure; Neutrophils; Peroxidase; Receptors, Immunologic; Receptors, Leukotriene B4 | 1989 |
Inflammatory mediators of experimental colitis in rats.
Colonic inflammation was induced in rats by intracolonic administration of 0.25 ml of 50% ethanol containing 30 mg of trinitrobenzene sulfonic acid (TNB). Control rats were treated with 0.25 ml of 50% ethanol or with 30 mg of TNB in 0.25 ml of saline. After 24 h, mucosal ulceration and hemorrhage were observed in TNB/ethanol-, 50% ethanol-, and to a lesser extent, in TNB/saline-treated rats. After 1 wk, mucosal damage was completely resolved in the 50% ethanol and TNB/saline-treated rats but the lesions in the TNB/ethanol-treated rats persisted and progressed to a chronic active inflammatory process after 3 wk. Myeloperoxidase activity was significantly elevated in mucosal scrapings from all treatment groups at all time intervals when macroscopic and microscopic mucosal injury was evident. Interleukin-1 was found to be the most sensitive indicator of mucosal inflammation, and its mucosal values correlated with myeloperoxidase activity. Leukotriene B4 was increased in control rats at 1 wk and in TNB/ethanol-treated rats at all time intervals. The maximal increase in leukotriene B4 was observed at 1 wk. Thromboxane B2 generation was reduced while platelet activating factor generation was not increased in TNB/ethanol-treated rats. These results indicate that in this TNB/ethanol model of gut inflammation, myeloperoxidase activity and interleukin-1 are reliable and sensitive indicators of colonic inflammation, and that thromboxane B2 is not involved in the acute lesions, whereas leukotriene B4 appears in the chronic active inflammatory response. Topics: Animals; Colitis; Colon; Ethanol; Interleukin-1; Intestinal Mucosa; Leukotriene B4; Male; Peroxidase; Platelet Activating Factor; Rats; Rats, Inbred Strains; Thromboxane B2; Trinitrobenzenesulfonic Acid | 1989 |
The effect of leukotriene-B4 receptor antagonist, SC-41930, on acetic acid-induced colonic inflammation.
SC-41930, 7-[3-(4-acetyl-3-methoxy-2-propylphenoxy)-propoxy]-3,4-dihydro-8-p ropyl- 2H-1-benzopyran-2-carboxylic acid, is a potent in vitro leukotriene-B4 (LTB4) receptor antagonist. LTB4 levels are elevated in colonic tissue of inflammatory bowel disease (IBD) patients which may account for the high degree of neutrophil (PMN) infiltration. The guinea pig acetic acid-induced colonic inflammation model has characteristics of IBD including PMN infiltration, edema, ulceration and necrosis. The model was used to evaluate the effect of SC-41930. SC-41930 was given orally, 30 min before and after intrarectal administration of 3% acetic acid. The PMN marker enzyme, myeloperoxidase, was measured along with histological evaluation to assess inflammation. Both parameters showed significantly less inflammation in SC-41930 treated animals with an oral ED50 of 20 mg/kg. These study results with an LTB4 receptor antagonist indicate a role for LTB4 in colonic inflammation and that an LTB4 receptor antagonist may be beneficial for treatment of IBD. Topics: Acetates; Animals; Benzopyrans; Colitis; Guinea Pigs; Male; Neutrophils; Peroxidase; Receptors, Immunologic; Receptors, Leukotriene B4 | 1989 |
Quantitative assay for acute intestinal inflammation based on myeloperoxidase activity. Assessment of inflammation in rat and hamster models.
An assay was devised to quantitate acute intestinal inflammation based on the assessment of myeloperoxidase activity. Myeloperoxidase is an enzyme found in neutrophils and, in much smaller quantities, in monocytes and macrophages. Myeloperoxidase was solubilized with hexadecyltrimethylammonium bromide and myeloperoxidase activity was measured with a dianisidine-H2O2 assay. In neutrophil suspensions, myeloperoxidase activity was directly related to cell number down to as few as 500 cells. Myeloperoxidase activity was assayed in two animal models of inflammation: acetic acid-induced colitis in rats and Clostridium difficile enterotoxin-induced enteritis in hamsters. In both models, the activity of myeloperoxidase solubilized from the inflamed tissue was directly proportional to the number of neutrophils seen in histologic sections. Histologic evaluation of neutrophil accumulation was performed by counting the number of neutrophils in a histologic section 0.18 mm long and 5 micron thick. In both animal models, myeloperoxidase activity was linearly related to neutrophil number from 400 and 4000 cells/mm. Myeloperoxidase activity from chronically inflamed colon, in which both neutrophils and histiocytes were present, was directly related to neutrophil content. Histiocytes did not contribute significantly to myeloperoxidase activity. The determination of myeloperoxidase activity in the intestine is a simple biochemical assay that can be used to quantitate inflammation. Topics: Acetates; Acetic Acid; Animals; Ascitic Fluid; Cell Separation; Clostridium Infections; Colitis; Cricetinae; Disease Models, Animal; Enteritis; Enterotoxins; Intestinal Mucosa; Leukocyte Count; Male; Mesocricetus; Neutrophils; Peroxidase; Peroxidases; Rats; Rats, Inbred Strains; Spectrophotometry | 1984 |