Modulation of 5-fluorouracil activation of toll-like/MyD88/NF-κB/MAPK pathway by Saccharomyces boulardii CNCM I-745 probiotic.

BACKGROUND AND AIM: Chemotherapy drugs that act via Toll-like receptors (TLRs) can exacerbate mucosal injury through the production of cytokines. Intestinal mucositis can activate TLR2 and TLR4, resulting in the activation of NF-κB. Intestinal mucositis characterized by intense inflammation is the main side effect associated with 5-fluorouracil (5-FU) treatment. Saccharomyces boulardii CNCM I-745 (S.b) is a probiotic yeast used in the treatment of gastrointestinal disorders. The main objective of the study was to evaluate the effect of S.b treatment on the Toll-like/MyD88/NF-κB/MAPK pathway activated during intestinal mucositis and in Caco-2 cells treated with 5-FU. METHODS: The mice were divided into three groups: saline (control), saline + 5-FU, and 5-FU + S.b (1.6 × 1010 colony forming units/kg). After 3 days of S.b administration by gavage, the mice were euthanized and the jejunum and ileum were removed. In vitro, Caco2 cells were treated with 5-FU (1 mM) alone or in the presence of lipopolysaccharide (1 ng/ml). When indicated, cells were exposed to S.b. The jejunum/ileum samples and Caco2 cells were examined for the expression or concentration of the inflammatory components. RESULTS: Treatment with S.b modulated the expressions of TLR2, TLR4, MyD88, NF-κB, ERK1/2, phospho-p38, phospho-JNK, TNF-α, IL-1ß, and CXCL-1 in the jejunum/ileum and Caco2 cells following treatment with 5-FU. CONCLUSION: Toll-like/MyD88/NF-κB/MAPK pathway are activated during intestinal mucositis and their modulation by S.b suggests a novel and valuable therapeutic strategy for intestinal inflammation.

Treatment with Saccharomyces boulardii reduces the inflammation and dysfunction of the gastrointestinal tract in 5-fluorouracil-induced intestinal mucositis in mice.

Intestinal mucositis is an important toxic side effect of 5-fluorouracil (5-FU) treatment. Saccharomyces boulardii is known to protect from intestinal injury via an effect on the gastrointestinal microbiota. The objective of the present study was to evaluate the effect of S. boulardii on intestinal mucositis induced by 5-FU in a murine model. Mice were divided into saline, saline (control)+5-FU or 5-FU+S. boulardii (16 × 109 colony-forming units/kg) treatment groups, and the jejunum and ileum were removed after killing of mice for the evaluation of histopathology, myeloperoxidase (MPO) activity, and non-protein sulfhydryl group (mainly reduced glutathione; GSH), nitrite and cytokine concentrations. To determine gastric emptying, phenol red was administered orally, mice were killed 20 min after administration, and the absorbance of samples collected from the mice was measured by spectrophotometry. Intestinal permeability was measured by the urinary excretion rate of lactulose and mannitol following oral administration. S. boulardii significantly reversed the histopathological changes in intestinal mucositis induced by 5-FU and reduced the inflammatory parameters: neutrophil infiltration (control 1·73 (SEM 0·37) ultrastructural MPO (UMPO)/mg, 5-FU 7·37 (SEM 1·77) UMPO/mg and 5-FU+S. boulardii 4·15 (SEM 0·73) UMPO/mg); nitrite concentration (control 37·00 (SEM 2·39) µm, 5-FU 59·04 (SEM 11·41) µm and 5-FU+S. boulardii 37·90 (SEM 5·78) µm); GSH concentration (control 477·60 (SEM 25·25) µg/mg, 5-FU 270·90 (SEM 38·50) µg/mg and 5-FU+S. boulardii 514·00 (SEM 38·64) µg/mg). Treatment with S. Boulardii significantly reduced the concentrations of TNF-α and IL-1ß by 48·92 and 32·21 % in the jejunum and 38·92 and 61·79 % in the ileum. In addition, S. boulardii decreased the concentrations of chemokine (C-X-C motif) ligand 1 by 5-fold in the jejunum and 3-fold in the ileum. Interestingly, S. boulardii reduced the delay in gastric emptying (control 25·21 (SEM 2·55) %, 5-FU 54·91 (SEM 3·43) % and 5-FU+S. boulardii 31·38 (SEM 2·80) %) and induced the recovery of intestinal permeability (lactulose:mannitol ratio: control 0·52 (SEM 0·03), 5-FU 1·38 (SEM 0·24) and 5-FU+S. boulardii 0·62 (SEM 0·03)). In conclusion, S. boulardii reduces the inflammation and dysfunction of the gastrointestinal tract in intestinal mucositis induced by 5-FU.

Inflammatory intestinal damage induced by 5-fluorouracil requires IL-4.

BACKGROUND: 5-Fluorouracil (5-FU) induces intestinal mucositis, which is characterized by epithelial ulcerations in the mucosa and clinical manifestations, such as pain and dyspeptic symptoms. Cytokines participate in the inflammatory and functional events of intestinal mucositis. IL-4 is an important mediator of intestinal inflammation, with either anti-inflammatory or pro-inflammatory functions, depending on the model of intestinal inflammation. This study aimed to evaluate the role of IL-4 in 5-FU-induced intestinal mucositis. METHODS: IL-4+/+ or IL-4-/- mice (25-30 g) were intraperitoneally injected with 5-FU (450 mg/Kg) or saline (C). After 3 days, the mice were sacrificed and the duodenum was evaluated for epithelial damage, MPO activity and cytokine concentration. RESULTS: 5-FU induced significant damage in the intestinal epithelium of IL-4+/+ mice (reduction in the villus/crypt ratio: control=3.31±0.21 µm, 5-FU=0.99±0.10 µm). However, the same treatment did not induce significant damage in IL-4-/- mice (5-FU=2.87±0.19 µm) compared to wild-type mice. 5-FU-induced epithelial damage increased the MPO activity (neutrophil number) and the level of pro-inflammatory cytokines (IL-4, TNF-α, IL-1ß and CXCL-8) in the duodenum. These results were not observed in IL-4-/- mice treated with 5-FU. CONCLUSION: Our data suggest that IL-4 participates as a pro-inflammatory cytokine in a 5-FU-induced intestinal damage model and suggests that IL-4 antagonists may be novel therapeutics for this condition.

Sulfated polysaccharide from the marine algae Hypnea musciformis inhibits TNBS-induced intestinal damage in rats.

Sulfated polysaccharides extracted from seaweed have important pharmacological properties. Thus, the aim of this study was to characterize the sulfated polysaccharide (PLS) from the algae Hypnea musciformis and evaluate its protective effect in colitis induced by trinitrobenzene sulfonic acid in rats. The sulfated polysaccharide possess a high molecular mass (1.24×10(5)gmol(-1)) and is composed of a κ-carrageenan, as depicted by FT-IR and NMR spectroscopic data. PLS was administered orally (10, 30, and 60mg/kg, p.o.) for three days, starting before TNBS (trinitrobenzene sulfonic acid) instillation (day 1). The rats were killed on day three, the portion of distal colon (5cm) was excised and evaluated macroscopic scores and wet weight. Then, samples of the intestinal were used for histological evaluation and quantification of glutathione, malonyldialdehyde acid, myeloperoxidase, nitrate/nitrite and cytokines. Our results demonstrate that PLS reduced the colitis and all analyzed biochemical parameters. Thus, we concluded that the PLS extracted from the marine algae H. musciformis reduced the colitis in animal model and may have an important promising application in the inflammatory bowel diseases.

Regulatory role of Lactobacillus acidophilus on inflammation and gastric dysmotility in intestinal mucositis induced by 5-fluorouracil in mice.

PURPOSE: Lactobacillus acidophilus is widely used for gastrointestinal disorders, but its role in inflammatory conditions like in chemotherapy-induced mucositis is unclear. Here, we report the effect of L. acidophilus on 5-fluorouracil-induced (5-FU) intestinal mucositis in mice. METHODS: Mice weighing 25-30 g (n = 8) were separated into three groups, saline, 5-FU, and 5-FU + L. acidophilus (5-FU-La) (16 × 10(9) CFU/kg). In the 5-FU-La group, L. acidophilus was administered concomitantly with 5-FU on the first day and alone for two additional days. Three days after the last administration of L. acidophilus, the animals were euthanized and the jejunum and ileum were removed for histopathological assessment and for evaluation of levels of myeloperoxidase activity, sulfhydryl groups, nitrite, and cytokines (TNF-α, IL-1ß, CXCL-1, and IL-10). In addition, we investigated gastric emptying using spectrophotometry after feeding a 1.5-ml test meal by gavage and euthanasia. Data were submitted to ANOVA and Bonferroni's test, with the level of significance at p < 0.05. RESULTS: Intestinal mucositis induced by 5-FU significantly (p < 0.05) reduced the villus height-crypt depth ratio and GSH concentration and increased myeloperoxidase activity and the nitrite concentrations compared with the control group. Furthermore, 5-FU significantly (p < 0.05) increased cytokine (TNF-α, IL-1ß, and CXCL-1) concentrations and decreased IL-10 concentrations compared with the control group. 5-FU also significantly (p < 0.05) delayed gastric emptying and gastrointestinal transit compared with the control group. All of these changes were significantly (p < 0.05) reversed by treatment with L. acidophilus. CONCLUSIONS: Lactobacillus acidophilus improves the inflammatory and functional aspects of intestinal mucositis induced by 5-FU.

Polysaccharides isolated from Digenea simplex inhibit inflammatory and nociceptive responses.

Polysaccharides (PLS) have notably diverse pharmacological properties. In the present study, we investigated the previously unexplored anti-inflammatory and antinociceptive activities of the PLS fraction isolated from the marine red alga Digenea simplex. We found that the PLS fraction reduced carrageenan-induced edema in a dose-dependent manner, and inhibited inflammation induced by dextran, histamine, serotonin, and bradykinin. The fraction also inhibited neutrophil migration into both mouse paw and peritoneal cavity. This effect was accompanied by decreases in IL1-ß and TNF-α levels in the peritoneal fluid. Pre-treatment of mice with PLS (60 mg/kg) significantly reduced acetic acid-induced abdominal writhing. This same dose of PLS also reduced total licking time in both phases of a formalin test, and increased latency in a hot plate test. Therefore, we conclude that PLS extracted from D. simplex possess anti-inflammatory and antinociceptive activities and can be useful as therapeutic agents against inflammatory diseases.

Sulfated-polysaccharide fraction extracted from red algae Gracilaria birdiae ameliorates trinitrobenzenesulfonic acid-induced colitis in rats.

OBJECTIVES: 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. METHODS: 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. KEY FINDINGS: 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. CONCLUSIONS: 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.