Pachymic acid protects against Crohn's disease-like intestinal barrier injury and colitis in miceby suppressingintestinal epithelial cell apoptosis via inhibiting PI3K/AKT signaling / 南方医科大学学报

OBJECTIVE@#To investigate the effect of pachymic acid (PA) against TNBS-induced Crohn's disease (CD)-like colitis in mice and explore the possible mechanism.@*METHODS@#Twenty-four C57BL/6J mice were randomized equally into control group, TNBS-induced colitis model group and PA treatment group. PA treatment was administered via intraperitoneal injection at the daily dose of 5 mg/kg for 7 days, and the mice in the control and model groups were treated with saline. After the treatments, the mice were euthanized for examination of the disease activity index (DAI) of colitis, body weight changes, colon length, intestinal inflammation, intestinal barrier function and apoptosis of intestinal epithelial cells, and the expressions of TNF-α, IL-6 and IL-1β in the colonic mucosa were detected using ELISA. The possible treatment targets of PA in CD were predicted by network pharmacology. String platform and Cytoscape 3.7.2 software were used to construct the protein-protein interaction (PPI) network. David database was used to analyze the GO function and KEGG pathway; The phosphorylation of PI3K/AKT in the colonic mucosal was detected with Western blotting.@*RESULTS@#PA significantly alleviated colitis in TNBS-treated mice as shown by improvements in the DAI, body weight loss, colon length, and histological inflammation score and lowered levels of TNF-α, IL-6 and IL-1β. PA treatment also significantly improved FITC-dextran permeability, serum I-FABP level and colonic transepithelial electrical resistance, and inhibited apoptosis of the intestinal epithelial cells in TNBS-treated mice. A total of 248 intersection targets were identified between PA and CD, and the core targets included EGFR, HRAS, SRC, MMP9, STAT3, AKT1, CASP3, ALB, HSP90AA1 and HIF1A. GO and KEGG analysis showed that PA negatively regulated apoptosis in close relation with PI3K/AKT signaling. Molecular docking showed that PA had a strong binding ability with AKT1, ALB, EGFR, HSP90AA1, SRC and STAT3. In TNBS-treated mice, PA significantly decreased p-PI3K and p-AKT expressions in the colonic mucosa.@*CONCLUSION@#PA ameliorates TNBS-induced intestinal barrier injury in mice by antagonizing apoptosis of intestinal epithelial cells possibly by inhibiting PI3K/AKT signaling.

Platycodon grandiflorus polysaccharide regulates colonic immunity through mesenteric lymphatic circulation to attenuate ulcerative colitis / 中国天然药物

Platycodon grandiflorus polysaccharide (PGP) is one of the main components of P. grandiflorus, but the mechanism of its anti-inflammatory effect has not been fully elucidated. The aim of this study was to evaluate the therapeutic effect of PGP on mice with dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) and explore the underlying mechanisms. The results showed that PGP treatment inhibited the weight loss of DSS-induced UC mice, increased colon length, and reduced DAI, spleen index, and pathological damage within the colon. PGP also reduced the levels of pro-inflammatory cytokines and inhibited the enhancement of oxidative stress and MPO activity. Meanwhile, PGP restored the levels of Th1, Th2, Th17, and Treg cell-related cytokines and transcription factors in the colon to regulate colonic immunity. Further studies revealed that PGP regulated the balance of colonic immune cells through mesenteric lymphatic circulation. Taken together, PGP exerts anti-inflammatory and anti-oxidant effect and regulates colonic immunity to attenuate DSS-induced UC through mesenteric lymphatic circulation.

Therapeutic effect of ursodeoxycholic acid-berberine supramolecular nanoparticles on ulcerative colitis based on supramolecular system induced by weak bond / 中国中药杂志

Ulcerative colitis(UC) is a recurrent, intractable inflammatory bowel disease. Coptidis Rhizoma and Bovis Calculus, serving as heat-clearing and toxin-removing drugs, have long been used in the treatment of UC. Berberine(BBR) and ursodeoxycholic acid(UDCA), the main active components of Coptidis Rhizoma and Bovis Calculus, respectively, were employed to obtain UDCA-BBR supramolecular nanoparticles by stimulated co-decocting process for enhancing the therapeutic effect on UC. As revealed by the characterization of supramolecular nanoparticles by field emission scanning electron microscopy(FE-SEM) and dynamic light scattering(DLS), the supramolecular nanoparticles were tetrahedral nanoparticles with an average particle size of 180 nm. The molecular structure was described by ultraviolet spectroscopy, fluorescence spectroscopy, infrared spectroscopy, high-resolution mass spectrometry, and hydrogen-nuclear magnetic resonance(H-NMR) spectroscopy. The results showed that the formation of the supramolecular nano-particle was attributed to the mutual electrostatic attraction and hydrophobic interaction between BBR and UDCA. Additionally, supramolecular nanoparticles were also characterized by sustained release and pH sensitivity. The acute UC model was induced by dextran sulfate sodium(DSS) in mice. It was found that supramolecular nanoparticles could effectively improve body mass reduction and colon shortening in mice with UC(P<0.001) and decrease disease activity index(DAI)(P<0.01). There were statistically significant differences between the supramolecular nanoparticles group and the mechanical mixture group(P<0.001, P<0.05). Enzyme-linked immunosorbent assay(ELISA) was used to detect the serum levels of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6), and the results showed that supramolecular nanoparticles could reduce serum TNF-α and IL-6 levels(P<0.001) and exhibited an obvious difference with the mechanical mixture group(P<0.01, P<0.05). Flow cytometry indicated that supramolecular nanoparticles could reduce the recruitment of neutrophils in the lamina propria of the colon(P<0.05), which was significantly different from the mechanical mixture group(P<0.05). These findings suggested that as compared with the mechanical mixture, the supramolecular nanoparticles could effectively improve the symptoms of acute UC in mice. The study provides a new research idea for the poor absorption of small molecules and the unsatisfactory therapeutic effect of traditional Chinese medicine and lays a foundation for the research on the nano-drug delivery system of traditional Chinese medicine.

Mechanism of tryptanthrin in treatment of ulcerative colitis in mice based on serum metabolomics / 中国中药杂志

This study aims to explore the effect of tryptanthrin on potential metabolic biomarkers in the serum of mice with ulcerative colitis(UC) induced by dextran sulfate sodium(DSS) based on liquid chromatography-mass spectrometry(LC-MS) and predict the related metabolic pathways. C57BL/6 mice were randomly assigned into a tryptanthrin group, a sulfasalazine group, a control group, and a model group. The mouse model of UC was established by free drinking of 3% DSS solution for 11 days, and corresponding drugs were adminsitrated at the same time. The signs of mice were observed and the disease activity index(DAI) score was recorded from the first day. Colon tissue samples were collected after the experiment and observed by hematoxylin-eosin(HE) staining. The levels of interleukin-4(IL-4), interleukin-10(IL-10), tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-8(IL-8) in the serum were measured by enzyme linked immunosorbent assay(ELISA). The serum samples were collected from 6 mice in each group for widely targeted metabolomics. The metabolic pathways were enriched by MetaboAnalyst 5.0. The results showed that compared with the model group, tryptanthrin treatment decreased the DAI score(P<0.05), alleviated the injury of the colon tissue and the infiltration of inflammatory cells, lowered the levels of proinflammatory cytokines, and elevated the levels of anti-inflammatory cytokines in the serum. The metabolomic analysis revealed 28 differential metabolites which were involved in 3 metabolic pathways including purine metabolism, arachidonic acid metabolism, and tryptophan metabolism. Tryptanthrin may restore the metabolism of the mice with UC induced by DSS to the normal level by regulating the purine metabolism, arachidonic acid metabolism, and tryptophan metabolism. This study employed metabolomics to analyze the mechanism of tryptanthrin in the treatment of UC, providing an experimental basis for the utilization and development of tryptanthrin.

Deficiency in glutathione synthesis and reduction contributes to the pathogenesis of colitis-related liver injury / 中南大学学报(医学版)

OBJECTIVES@#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.@*METHODS@#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.@*RESULTS@#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 P<0.01), the serum aspartate aminotransferase level and hepatic histopathologic score were also obviously elevated at the 7th day post TNBS (all P<0.05). There was a significant positive correlation between the degree of liver injury and the severity of colonic lesions (P=0.000 1). Moreover, compared with the control, hepatic GSH content and the activity of GSH-Px and GR were all significantly decreased at the 3rd and 5th days post TNBS (P<0.05 or P<0.01), and the protein expressions of GCL, GSH-Px, and GR were all obviously down-regulated at the 3rd, 5th, and 7th days post TNBS (P<0.05 or P<0.01).@*CONCLUSIONS@#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.

Antioxidant evaluation of the aqueous extract of hulls of Campsiandra laurifolia in colitis induced by acetic acid in Wistar rats / Avaliação antioxidante do extrato aquoso de cascas de Campsiandra laurifolia na colite induzida por ácido acético em ratos Wistar

Abstract Due to the ethnopharmacological use of Campsiandra laurifolia (Fabaceae), popularly known as Acapurana, to treat wounds and ulcers, associated with the lack of alternative treatments for intestinal inflammations such as ulcerative colitis (UC), the present work sought to characterize its phytochemical and antioxidant activities, and to evaluate remedial action in experimental colitis with acetic acid. Phytochemical analyzes were performed through qualitative and quantitative colorimetric tests of the main secondary metabolites. In the colitismodel, 24male Wistar rats aged±60 days oldwere used, divided into 4 groups: Control (CO) control+aqueous extract of C. laurifolia 50mg/kg (CO+A50); Colitis (CL); and Colitis+aqueous extract of C. laurifolia 50 mg/kg (CL+ A50).Measurement of sphincter anal pressure and histological tests of the large intestine, lipoperoxidation (LPO), enzymeactivity of superoxide dismutase (SOD), and levels of glutathione (GSH)were performed. For statistical analysis, the oxidative stress (OS) results were expressed as means±standard error, adopting a significance level of p < 0.05. The screening indicated the presence of flavonoids, saponins and tannins in the extract, with high levels of phenolic

Resumo Devido ao uso etnofarmacológico de Campsiandra laurifolia (Fabaceae), popularmente conhecida comoAcapurana, para tratar feridas e úlceras, associado à falta dealternativas de tratamentos para as inflamações intestinais como a retocolite ulcerativa (RCU), o presente trabalho buscou caracterizar sua constituição fitoquímica, sua atividade antioxidante, e avaliar sua ação reparadora na colite experimental com ácido acético. As análises fitoquímicas foram realizadas por meio de ensaios colorimétricos qualitativos e quantitativos dos principaismetabólitos secundários.Nomodelo de colite, foramutilizados 24 ratos machos Wistar de±60 dias de idade, divididos em 4 grupos: Controle (CO), controle+ extrato aquoso de C. laurifolia 50mg/kg (CO+A50); Colite (CL); e Colite+extrato aquoso de C. laurifolia (CL+ A50). Foram realizadas aferições da pressão anal esfincteriana e avaliações histológicas do intestino grosso, lipoperoxidação (LPO), atividade da enzima superóxido dismutase (SOD) e níveis da glutationa (GSH). Para a análise estatística, resultados do estresse oxidativo (EO) foram expressos em médias±erro padrão, adotando um nível de significância de p < 0,05. O screening indicou no extrato a presença de flavonoides, saponinas e taninos com altos teores de compostos fenólicos e taninos, relacionando-os a uma elevada capacidade antioxidante. Na análise histológica, o grupo CL apresentou perda das criptas, do edema e do infiltrado inflamatório. O uso do extrato de C. laurifolia reestruturou as criptas, diminuiu o edema e aumentou a pressão anal esfincteriana, com diminuição da LPO, da SOD, e aumento da GSH. Sugere-se que o uso do extrato de C. laurifolia diminui o EO por seu poder antioxidante, conferido pelos compostos fenólicos presentes no extrato.

Expressão de e-caderina e claudina-3 no epitélio cólico após terapia com infliximabe: modelo experimental de colite de exclusão / Expression of e-cadherin and claudin-3 in the colonic epithelium after the infliximab therapy: experimental model of disuse colitis

RESUMO - RACIONAL: A etiopatogenia da colite por desuso (DC) ainda não foi totalmente elucidada. As principais teorias consideram que a doença pode estar relacionada ao aumento de bactérias anaeróbias, falta de suprimento de ácidos graxos de cadeia curta (AGCC) e distúrbios imunológicos que se desenvolvem em segmentos colorretais desprovidos de trânsito fecal. OBJETIVO: Verificar se a aplicação de infliximabe modifica o conteúdo tecidual das proteínas E-caderina e claudina-3 no epitélio cólico de ratos sem trânsito intestinal. MÉTODOS: Vinte dois ratos foram submetidos a derivação do trânsito intestinal pelo procedimento de Hartmann. Eles permaneceram com o ostoma por 12 semanas para permitir o desenvolvimento da colite de exclusão. Em seguida, foram divididos em três grupos experimentais: seis animais receberam 2,0 ml de solução salina/semana, oito infliximabe na dose de 5 mg/Kg/semana e, os demais, infliximabe na dose de 10 mg/Kg/semana por 5 semanas consecutivas. Em seguida, os animais foram eutanasiados e os segmentos cólicos com e sem trânsito intestinal foram removidos. A colite por desuso foi diagnosticada pelas alterações histológicas definidas por uma escala previamente validada. Expressão tecidual de E-caderina e claudina-3 foi avaliada por imuno-histoquímica, e o conteúdo tecidual de ambas as proteínas foi quantificado por análise de imagem assistida por computador. RESULTADOS: Segmentos cólicos exclusos de trânsito fecal apresentaram maior grau de inflamação do que os expostos ao trânsito fecal. Inflamação foi menor nos animais tratados com infliximabe, independente da dose utilizada. Níveis de E-caderina e claudina-3 estavam reduzidos no cólon excluso. O tratamento com infliximabe aumentou os níveis das proteínas em segmentos do cólon sem trânsito intestinal, principalmente nos animais que receberam a dose de 10mg/kg/semana. CONCLUSÃO: Infliximabe reduz inflamação nos segmentos do cólon excluso e aumenta o conteúdo tecidual de E-caderina e claudina-3, especialmente na concentração de 10mg/kg/semana.

ABSTRACT - BACKGROUND: The etiopathogenesis of disuse colitis (DC) has not yet been fully elucidated. The main theories consider that the disease may be related to an increase in anaerobic bacteria, the lack of short-chain fatty acid (SCFA) supply, and immunological disorders that develop in the colorectal segments devoid of fecal transit. AIM: The aim of this study was to verify whether the application of infliximab modifies the tissue content of E-cadherin and claudin-3 proteins in colonic epithelium of rats devoid of intestinal transit. METHODS: A total of 22 rats underwent intestinal transit bypass using Hartmann's procedure. They remained with the shunt for 12 weeks to allow the development of DC. Later, they were divided into three experimental groups: six animals received 2.0 mL saline solution/week, eight received infliximab at a dose of 5 mg/kg/week, and eight received infliximab at a dose of 10 mg/kg/week for 5 consecutive weeks. At the end of this period, the animals were euthanized, and the colonic segments with and without intestinal transit were removed. DC was diagnosed based on the histological changes defined by a previously validated scale. The tissue expression of E-cadherin and claudin-3 was assessed by immunohistochemistry, and the tissue content of both proteins was quantified by computer-aided image analysis. RESULTS: The colonic segments excluded from fecal transit showed a higher degree of inflammation than those exposed to fecal transit. The degree of inflammation was lower in animals treated with infliximab, regardless of the dose used. The levels of E-cadherin and claudin-3 were reduced in the excluded colon. Treating animals with infliximab increased the levels of both proteins in the colonic segments without intestinal transit, especially in animals receiving a dose of 10 mg/kg/week. CONCLUSION: Infliximab therapy reduces inflammation in the colonic segments excluded from intestinal transit and increases the tissue content of E-cadherin and claudin-3 proteins, especially when used at a concentration of 10 mg/kg/week.

Antioxidant effect of mesalazine in the experimental colitis model induced by acetic acid / Efeito antioxidante da mesalazina no modelo de colite experimental induzida por ácido acético

Abstract Introduction Inflammatory bowel disease (IBD) is characterized by a chronic inflammation of the gastrointestinal tract, without specific cause or pathogen. Objective The effect of mesalazine in a colitis model induced by acetic acid (AA) was evaluated. Methods We used 40 Wistar rats, ±350 g, divided into 4 groups: control (CO); control + mesalazine (CO + M); colitis (CL) and colitis + M (CL + M) at 24 and 48 h of treatment. The animals received the substances by an intracolonic enema of AA 4% and treatment with mesalazine PO 20 mg/kg after colitis induction. Results Mesalazine reduced tissue damage in the gut, normalized sphincter anal pressure levels and decreased lipid peroxidation, metabolites of nitric oxide and iNOS and NF-kB expression in the treated groups in both treatment time points (24 and 48 h), as well as the activity of antioxidant enzymes. Conclusion Mesalazine was effective in reducing tissue damage and oxidative and inflammatory damage, restored antioxidant capacity and increased anal sphincter pressure levels, possibly due to its antioxidant effect.

Resumo Introdução A doença inflamatória intestinal (DII) caracteriza-se por uma inflamação crônica do trato gastrointestinal sem uma causa ou patógeno específico. Objetivo Foi avaliado o efeito da mesalazina no modelo de colite induzida por ácido acético (AA). Material e métodos Foram utilizados 40 ratos wistar, ±350 gramas, divididos em 4 grupos: Controle (CO); Controle + Mesalasina (CO + M); Colite (CL) e Colite + M (CL + M) nos tempos de 24 e 48 horas de tratamento. Os animais foram submetidos à administração intracolônica por enema com solução de AA a 4% e tratamento com mesalazina na dose oral de 20 mg/kg após a indução da colite. Resultados A mesalazina reduziu as lesões teciduais no intestino, normalizou os níveis de pressão anal esfincteriana, reduziu a lipoperoxidação, metabólitos do óxido nítrico e expressão da iNOS e do NF-kB nos grupos tratados em ambos os tempos de tratamento (24 e 48 horas), bem como a atividade das enzimas antioxidantes. Conclusão A mesalazina demonstrou eficácia na redução das lesões teciduais, danos oxidativos e inflamatórios, restabeleceu a capacidade antioxidante e aumentou os níveis de pressão anal esfincteriana, possivelmente pelo seu efeito antioxidante.

L-carnitine has a protective effect on the colonic mucosa during abdominopelvic radiotherapy in rats

ABSTRACT PURPOSE: To evaluate histopathologically the radioprotective effect of L-carnitine on the colonic mucosa in rats undergoing abdominopelvic irradiation. METHODS: Thirty-two rats were randomly assigned to four experimental groups: intraperitoneal administration of normal saline (group 1) or L-carnitine (300 mL/kg; group 2), followed in groups 3 and 4, respectively, by one dose of abdominopelvic radiation (20 Gy) 30 min later. Rats were sacrificed 5 days after radiation, and their descending colons were resected for histopathological evaluation of the presence and severity of damage. RESULTS: Average damage scores did not differ significantly between groups 1 and 2 (0.13 ± 0.35 and 0.25 ± 0.46, respectively); the group 3 score was highest (10.25 ± 0.71), and the group 4 score (3.63 ± 1.41) was significantly lower than that of group 3 (both p = 0.0001). Pre-radiation L-carnitine administration significantly reduced mucosal thinning, crypt distortion, reactive atypia, inflammation, cryptitis, and reactive lymph-node hyperplasia (all p < 0.01). CONCLUSIONS: L-carnitine had a radioprotective effect on rat colonic mucosa. L-carnitine use should be explored for patients with gastrointestinal cancer, who have reduced serum L-carnitine levels.

Secondary bile acids effects in colon pathology. Experimental mice study

ABSTRACTPURPOSE:To assess whether deoxycholic acid (DOC) and lithocholic acid (LCA) administered in a period of six months in a concentration of 0.25% may have a carcinogenic role in mice colon.METHODS:The study used C57BL6 female mice divided into four groups. The control group received a balanced diet and the others received diets supplemented with 0.25% DOC, 0.25% LCA and 0.125% DOC+0.125% LCA, respectively. After euthanasia, the lesions found in the resected gastrointestinal tracts were stained with hematoxylin-eosin and examined microscopically.RESULTS:No gastrointestinal tract changes were observed in the control group, while hyperplastic Peyer's patches in the small intestine, flat adenomas with mild dysplasia and chronic colitis at the level of the colon were found in all three test groups. The colonic lesions prevailed in the proximal colon. The highest number of flat adenoma lesions (8), hyperplasia of Peyer's patches (25) and chronic colitis (2) were found in mice fed with diet and LCA.CONCLUSION: Precancerous or cancerous pathological lesions could not be identified. Instead, adenomatous colonic injuries occurred in a shorter period of time (six months), compared to the reported data.

Changes in the Expression and Distribution of Claudins, Increased Epithelial Apoptosis, and a Mannan-Binding Lectin-Associated Immune Response Lead to Barrier Dysfunction in Dextran Sodium Sulfate-Induced Rat Colitis

BACKGROUND/AIMS: This animal study aimed to define the underlying cellular mechanisms of intestinal barrier dysfunction. METHODS: Rats were fed 4% with dextran sodium sulfate (DSS) to induce experimental colitis. We analyzed the sugars in 24-hour urine output by high pressure liquid chromatography. The expression of claudins, mannan-binding lectin (MBL), and MBL-associated serine proteases 2 (MASP-2) were detected in the colonic mucosa by immunohistochemistry; and apoptotic cells in the colonic epithelium were detected by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling method assay. RESULTS: The lactulose and sucralose excretion levels in the urine of rats with DSS-induced colitis were significantly higher than those in the control rats. Mannitol excretion was lower and lactulose/mannitol ratios and sucralose/mannitol ratios were significantly increased compared with those in the control group (p<0.05). Compared with the controls, the expression of sealing claudins (claudin 3, claudin 5, and claudin 8) was significantly decreased, but that of claudin 1 was increased. The expression of pore-forming claudin 2 was upregulated and claudin 7 was downregulated in DSS-induced colitis. The epithelial apoptotic ratio was 2.8%+/-1.2% in controls and was significantly increased to 7.2%+/-1.2% in DSS-induced colitis. The expression of MBL and MASP-2 in the intestinal mucosa showed intense staining in controls, whereas there was weak staining in the rats with colitis. CONCLUSIONS: There was increased intestinal permeability in DSS-induced colitis. Changes in the expression and distribution of claudins, increased epithelial apoptosis, and the MASP-2-induced immune response impaired the intestinal epithelium and contributed to high intestinal permeability.

Electroacupuncture ameliorates experimental colitis induced by TNBS through activation of interleukin-10 and inhibition of iNOS in mice

PURPOSE:To study the anti-inflammatory actions of electroacupuncture (EAc) on an experimental colitis model in mice.METHODS: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).RESULTS: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. CONCLUSION: 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.

Electroacupuncture ameliorates experimental colitis induced by TNBS through activation of interleukin-10 and inhibition of iNOS in mice

PURPOSE: To study the anti-inflammatory actions of electroacupuncture (EAc) on an experimental colitis model in mice. METHODS: 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). RESULTS: 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. CONCLUSION: 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. .

Nitric oxide ineerferes with hypoxia signaling during colonic inflamaation / A interferência do óxido nítrico na sinalização da hipóxia durante a inflamação colônica

Context Intestinal inflammation can induce a local reduction in oxygen levels that triggers an adaptive response centered on the expression of hypoxia-inducible factors (HIFs). Nitric oxide, a well-described inflammatory mediator, may interfere with hypoxia signaling. Objectives We aimed to evaluate the role of nitric oxide in hypoxia signaling during colonic inflammation. Methods Colitis was induced by single (acute) or repeated (reactivated colitis) trinitrobenzenosulfonic acid administration in rats. In addition, one group of rats with reactivated colitis was also treated with Nw-Nitro-L-arginine methyl ester hydrochloride to block nitric oxide synthase. Colitis was assessed by macroscopic score and myeloperoxidase activity in the colon samples. Hypoxia was determined using the oxygen-dependent probe, pimonidazole. The expression of HIF-1α and HIF-induced factors (vascular endothelial growth factor - VEGF and apelin) was assessed using Western blotting. Results The single or repeated administration of trinitrobenzenosulfonic acid to rats induced colitis which was characterized by a high macroscopic score and myeloperoxidase activity. Hypoxia was observed with both protocols. During acute colitis, HIF-1α expression was not increased, but VEGF and apelin were increased. HIF-1α expression was inhibited during reactivated colitis, and VEGF and apelin were not increased. Nw-Nitro-L-arginine methyl ester hydrochloride blockade during reactivated colitis restored HIF-1α, VEGF and apelin expression. Conclusions Nitric oxide could interfere with hypoxia signaling during reactivated colitis inflammation modifying the expression of proteins regulated by HIF-1α. .

Contexto A inflamação intestinal pode induzir uma redução local nos níveis de oxigênio e ativar uma resposta adaptativa relacionada à expressão de fatores induzíveis por hipóxia (HIFs). O óxido nítrico, um mediador inflamatório bem descrito, pode interferir com a sinalização de hipóxia. Objetivos O objetivo foi avaliar o papel do óxido nítrico na sinalização de hipóxia durante a inflamação colônica. Métodos A colite foi induzida em ratos pela administração única (aguda) ou repetida (com reativações) de ácido trinitrobenzenosulfônico. Adicionalmente, um grupo de ratos de colite com reativações foi também tratado com Nw-Nitro-L-arginina metil éster para inibir a óxido nítrico sintase. A colite foi avaliada através do escore macroscópico e da atividade de mieloperoxidase em amostras de cólon. A hipóxia foi determinada usando uma sonda dependente de oxigênio, o pimonidazol. A expressão de HIF-1α e de fatores induzidos pelo HIF (factor de crescimento endotelial vascular - VEGF e apelina) foi avaliada pela técnica de Western blotting. Resultados A administração única ou repetida de ácido trinitrobenzenosulfônico a ratos induziu colite que foi caracterizada por um alto escore macroscópico e alta atividade de mieloperoxidase. Hipóxia foi observada em ambos os protocolos. Durante a colite aguda, a expressão de HIF-1α não aumentou, enquanto a de VEGF e apelina aumentou. A expressão de HIF-1α esteve inibida durante a colite com reativações e, a expressão de VEGF e apelina não se modificou. O bloqueio com Nw-Nitro-L-arginina metil éster durante a colite com reativações restabeleceu a expressão de HIF-1α, VEGF e ...

Protective effect of Dillenia indica L. on acetic acid induced colitis in mice.

The inflammatory bowel disease (IBD) is an idiopathic, immune mediated and chronic inflammation of the intestine. The study aimed to elucidate the ameliorative effect of methanolic extract of Dillenia indica (DIME), hexane fraction (HFDI) and chloroform fraction (CFDI) of Dillenia indica in acetic acid induced experimental colitis in mice. Macroscopic score, colon weight, colonic catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), myeloperoxidase (MPO), malondialdehyde (MDA), tumor necrosis factor (TNF-α), and histological changes were recorded after the treatment regimen of 7 days. Intra-rectal instillation of acetic acid caused enhanced macroscopic score, colon weight, colonic MPO, MDA, and TNF-α level. It caused significant decreased level of CAT, SOD and GSH. DIME (800 mg/kg), HFDI (200 mg/kg) and CFDI (200 mg/kg) treatment exhibited significant effect in lowering macroscopic score, colon weight, MPO, MDA, TNF-α levels and elevation of CAT, GSH and SOD levels. The results suggest that D. indica has ameliorating effects on experimental colitis by inhibiting the proinflammatory mediators like TNF-α production.

Benzoxazole Derivative B-98 Ameliorates Dextran Sulfate Sodium-induced Acute Murine Colitis and the Change of T Cell Profiles in Acute Murine Colitis Model / 대한소화기학회지

BACKGROUND/AIMS: The unique role of enzyme 5-lipoxygenase (5-LO) in the production of leukotrienes makes it a therapeutic target for inflammatory bowel disease (IBD). The aim of this study was to evaluate the effects of B-98, a newly synthesized benzoxazole derivatives and a novel 5-LO inhibitor, in a mouse model of IBD induced by dextran sulfate sodium (DSS). METHODS: C57BL/6 mice were randomly assigned to four groups: normal control, DSS colitis (DSS+saline), low dose B-98 (DSS+B-98 20 mg/kg) and high dose B-98 (DSS+B-98 100 mg/kg). B-98 was administered with 3% DSS intraperitoneally. The severity of the colitis was assessed via the disease activity index (DAI), colon length, and histopathologic grading. The production of inflammatory cytokines interleukin (IL)-6 was determined by RT-PCR. Th cells were examined for the proportion of Th1 cell, Th2 cell, Th9 cell, Th17 cell and Treg cell using intracellular cytometry. RESULTS: The B-98 group showed lower DAI, less shortening of the colon length and lower histopathologic grading compared with the DSS colitis group (p<0.01). The expression of IL-6 in colonic tissue was significantly lower in the B-98 groups than the DSS colitis group (p<0.05). The cellular profiles revealed that the Th1, Th9 and Th17 cells were increased in the DSS colitis group compared to the B-98 group (p<0.05). CONCLUSIONS: Our results suggest that acute intestinal inflammation is reduced in the group treated with B-98 by Th1, Th9 and Th17 involved cellular immunity.

Oxidative stress and changes in the content and pattern of tissue expression of ß-catenin protein in diversion colitis

OBJECTIVE: The aim of this study is to verify if oxidative stress is related to changes in content and pattern of β-catenin protein expression in an experimental model of diversion colitis. METHODS: Sixty Wistar rats were submitted to intestinal bypass. The animals were divided into three groups according to the sacrifice to take place in six, 12 and 18 weeks. For each group, five animals only underwent laparotomy (control). The presence of colitis was diagnosed by histological study, and its severity, by inflammation grading scale. Cellular oxidative stress was measured by comet assay. Tissue expression of β-catenin protein was analyzed by the immunohistochemistry and quantification of its tissue content by computerized morphometry. Statistical analysis was performed with the Student's t-test, median, Mann-Whitney, ANOVA and Kruskal-Wallis, adopting a significance level of 5% (p <0.05). RESULTS: Colon segments without fecal stream developed colitis, which worsened with time of exclusion. Segments without fecal stream suffer higher levels of oxidative stress when compared to those with stream, and it worsens with time of exclusion. The levels of cellular oxidative stress are directly related to the degree of inflammation. The total content of ß-catenin in segments without fecal stream reduces after six weeks, and does not vary thereafter. The content of β-catenin in the apical portion of the colon crypts decreases with time, whereas in the basal region, it increases. The total content of ß-catenin is inversely related to the degree of inflammation and levels of tissue oxidative stress levels. CONCLUSION: There are changes in tissue content of E-cadherin and increased expression of ß-catenin in proliferative regions of colonic crypts, related with oxidative tissue stress. (AU)

OBJETIVO: O objetivo do presente estudo é avaliar a relação entre estresse oxidativo e conteúdo tecidual de β-catenina em modelo experimental de colite de exclusão. MÉTODOS: Sessenta ratos Wistar foram submetidos à derivação intestinal e divididos em três grupos experimentais segundo o sacrifício ser realizado em 6, 12 e 18 semanas. Para cada grupo, cinco animais foram submetidos apenas a laparotomia (controle). A colite foi diagnosticada por estudo histológico, enquanto sua intensidade por escala de graduação inflamatória. Os níveis de estresse oxidativo foram mensurados pelo ensaio cometa, enquanto a expressão e o conteúdo tecidual de ß-catenina por imunoistoquímica e morfometria computadorizada, respectivamente. Os resultados foram analisados pelos testes t de Student, Mann Whitney, ANOVA e Kruskal-Wallis, estabelecendo-se nível de significância de 5% (p<0,05). RESULTADOS: Nos segmentos sem trânsito fecal ocorre desenvolvimento de colite que piora com o tempo de exclusão. Segmentos sem trânsito sofrem maiores níveis de estresse oxidativo quando comparados àqueles com trânsito, piorando com o tempo de exclusão. Os níveis de estresse oxidativo encontram-se diretamente relacionados a piora da inflamação. O conteúdo total de ß-catenina no cólon sem trânsito reduz após seis semanas de exclusão. O conteúdo de ß-catenina no ápice das criptas cólicas diminui com o tempo, enquanto na região basal, aumenta. O conteúdo total da β-catenina encontra-se inversamente relacionado ao grau de inflamação e aos níveis de estresse oxidativo. CONCLUSÃO: Existe redução no conteúdo de ß-catenina, principalmente no ápice das glândulas cólicas e aumento nas regiões basais, relacionadas à piora do estresse oxidativo. (AU)

The effect of progesterone in the prevention of the chemically induced experimental colitis in rats / Efeito da progesterona na prevenção de colite experimental induzida quimicamente em ratos

PURPOSE: To study the effects of progesterone on an experimental colitis model. METHODS: Wistar albino rats were treated subcutaneously with 2mg/kg once a day during seven days Colitis was induced by intrarectal administration of 5mg trinitrobenzene sulfonic acid (TNBS). Disease activities, macroscopic and microscopic scores were evaluated. To determine the response provoked by progesterone we measured Colonic malondialdehyde (MDA), TNF alfa, IL-6 and Nitric oxide (NO) levels in addition to the MPO (Myeloperoxidase) and caspase-3 activities. RESULTS: Progesterone ameliorated significantly the macroscopic and microscopic scores. TNBS-induced colitis significantly increased the colonic MDA levels and caspase-3 activities in group 2 in comparison to the control group. The results of the study revealed a decline in MDA, NO, IL6 and TNF-α levels in the colon tissue and in blood due to progesterone therapy in group 3 when compared to the group 2, a significant improvement. Progesterone treatment was associated with decreased MDA, MPO, TNF alfa and caspase-3 activity. CONCLUSION: Progesterone therapy decreased oxidative damage in the colonic mucosa.

OBJETIVO: Investigar os efeitos da progesterona em um modelo de colite experimental. MÉTODOS: Ratos albinos Wistar foram tratados subcutaneamente com 2mg/kg por dia durante sete dias. A colite foi induzida por administração intrarretal de 5mg ácido sulfônico trinitrobenzeno (TNBS). Foram avaliadas as atividades da doença, escores macroscópicos e microscópicos Para determinar a resposta provocada pela progesterona foi medida no cólon os níveis de malondialdeído (MDA), TNF alfa, IL-6 e óxido nítrico (NO), além da atividade da MPO (Myeloperoxidase) e caspase-3. RESULTADOS: A progesterone melhorou significantemente os escores macroscópicos e microscópicos. A colite induzida pelo TNBS significantemente aumentou os níveis colônicos de MDA e a atividade da caspase-3 no grupo 2 em comparação com o grupo controle. Os resultados do estudo revelaram um declínio nos níveis de MDA, NO, IL6 e TNF-α no tecido colônico e no sangue devido à terapia com a progesterona no grupo 3 quando comparado ao grupo 2. O tratamento com a progesterona foi associado com decréscimo do MDA, MPO, TNF alfa e atividade da caspase-3. CONCLUSÃO: A terapia com progesterona decresce o dano oxidativo na mucosa do cólon.

Trichinella spiralis Infection Suppressed Gut Inflammation with CD4+CD25+Foxp3+ T Cell Recruitment

In order to know the effect of pre-existing Trichinella spiralis infection on experimentally induced intestinal inflammation and immune responses, we induced colitis in T. spiralis-infected mice and observed the severity of colitis and the levels of Th1, Th2, and regulatory cytokines and recruitment of CD4+CD25+Foxp3+ T (regulatory T; Treg) cells. Female C57BL/6 mice were infected with 250 muscle larvae; after 4 weeks, induction of experimental colitis was performed using 3% dextran sulfate sodium (DSS). During the induction period, we observed severity of colitis, including weight loss and status of stool, and evaluated the disease activity index (DAI). A significantly low DAI and degree of weight loss were observed in infected mice, compared with uninfected mice. In addition, colon length in infected mice was not contracted, compared with uninfected mice. We also observed a significant increase in production of pro-inflammatory cytokines, IL-6 and IFN-gamma, in spleen lymphocytes treated with DSS; however, such an increase was not observed in infected mice treated with DSS. Of particular interest, production of regulatory cytokines, IL-10 and transforming growth factor (TGF)-beta, in spleen lymphocytes showed a significant increase in mice infected with T. spiralis. A similar result was observed in mesenteric lymph nodes (MLN). Subsets of the population of Treg cells in MLN and spleen showed significant increases in mice infected with T. spiralis. In conclusion, T. spiralis infection can inhibit the DSS-induced colitis in mice by enhancing the regulatory cytokine and Treg cells recruitment.