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ABSTRACT: Carrageenan (CGN) is a high molecular weight sulphated polysaccharide derived from red seaweeds. In rodents, its degraded forms (dCGN) can induce intestinal inflammation associated with macrophage recruitment and activation. The aim of this study was: 1) to analyze the size-dependent effects of dCGN on colon inflammation in vivo, and 2) to correlate these effects with monocyte/macrophage proliferation, cytokine production and expression of various cell surface antigens including ICAM-1 adhesion molecule. Peripheral blood monocytes (PBM) and THP-1 monocytic cells were cultured in the presence of either 10 or 40 kDa, dCGN. The 40 kDa, but not the 10 kDa dCGN, induced colitis in in vivo. Degraded CGN inhibited THP-1 cell proliferation in vitro, arresting the cells in G1 phase. In addition, dCGN increased ICAM-1 expression in both PBM and THP-1 cells with a major effect seen after 40 kDa dCGN exposure. Also, dCGN stimulated monocyte aggregation in vitro that was prevented by incubation with anti-ICAM-1 antibody. Finally, dCGN stimulated TNF-alpha expression and secretion by both PBM and THP-1 cells. All these effects were linked to NF-kappaB activation. These data strongly suggest that the degraded forms of CGN have a pronounced effect on monocytes, characteristic of an inflammatory phenotype.
PLoS ONE 01/2010; 5(1):e8666. · 4.09 Impact Factor
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ABSTRACT: Dysregulation of intestinal epithelial cell performance is associated with an array of pathologies whose onset mechanisms are incompletely understood. While whole-genomics approaches have been valuable for studying the molecular basis of several intestinal diseases, a thorough analysis of gene expression along the healthy gastrointestinal tract is still lacking. The aim of this study was to map gene expression in gastrointestinal regions of healthy human adults and to implement a procedure for microarray data analysis that would allow its use as a reference when screening for pathological deviations. We analyzed the gene expression signature of antrum, duodenum, jejunum, ileum, and transverse colon biopsies using a biostatistical method based on a multivariate and univariate approach to identify region-selective genes. One hundred sixty-six genes were found responsible for distinguishing the five regions considered. Nineteen had never been described in the GI tract, including a semaphorin probably implicated in pathogen invasion and six novel genes. Moreover, by crossing these genes with those retrieved from an existing data set of gene expression in the intestine of ulcerative colitis and Crohn's disease patients, we identified genes that might be biomarkers of Crohn's and/or ulcerative colitis in ileum and/or colon. These include CLCA4 and SLC26A2, both implicated in ion transport. This study furnishes the first map of gene expression along the healthy human gastrointestinal tract. Furthermore, the approach implemented here, and validated by retrieving known gene profiles, allowed the identification of promising new leads in both healthy and disease states.
Mammalian Genome 09/2009; 20(8):516-27. · 2.89 Impact Factor
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ABSTRACT: The objective of the present study was to determine whether acacia gum (GUM) is a prebiotic fibre and to evaluate its intestinal tolerance in healthy subjects. The effects of increasing doses of GUM were compared to those of sucrose (SUC) on stool output, concentration of the main bacterial populations in stools, and occurrence and severity of intestinal symptoms (flatulence, bloating, abdominal cramps, diarrhoea). Ingestion of GUM 10 and 15 g/day for 10 days increased total lactic acid-producing bacteria and bifidobacteria counts in stools, without affecting total anaerobe and aerobe counts. The magnitude of this selective effect was greater in subjects with a low initial faecal concentration of bifidobacteria. Faecal digestibility of GUM was around 95% and its caloric value was estimated to range between 5.5 and 7.7 kJ/g. In addition, stool weight increased 30% because of greater faecal water content. Digestive tolerance of GUM was high and not statistically different from that of SUC up to a daily dose of 30 g. Above this dose, the main complaint was excessive flatulence. However, the mean degree of severity remained mild (<1), even at doses >50 g/day. Other intestinal events were rarely reported. Thus GUM is a very well tolerated dietary fibre with bifidogenic properties believed to benefit intestinal health.
07/2009; 15(1):43-50.
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Francois-Pierre J Martin,
Norbert Sprenger,
Ivan K S Yap,
Yulan Wang,
Rodrigo Bibiloni,
Florence Rochat,
Serge Rezzi, Christine Cherbut,
Sunil Kochhar,
John C Lindon,
Elaine Holmes,
Jeremy K Nicholson
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ABSTRACT: Coevolution shapes interorganismal crosstalk leading to profound and diverse cellular and metabolic changes as observed in gut dysbiosis in human diseases. Here, we modulated a simplified gut microbiota using pro-, pre-, and synbiotics to assess the depth of systemic metabolic exchanges in mice, using a multicompartmental modeling approach with metabolic signatures from 10 tissue/fluid compartments. The nutritionally induced microbial changes modulated host lipid, carbohydrate, and amino acid metabolism at a panorganismal scale. Galactosyl-oligosaccharides reduced lipogenesis, triacylglycerol incorporation into lipoproteins and triglyceride concentration in the liver and the kidney. Those changes were not correlated with decreased plasma lipoproteins that were specifically induced by L. rhamnosus supplementation. Additional alteration of transmethylation metabolic pathways (homocysteine-betaine) was observed in the liver and the pancreas following pre- and synbiotic microbial modulation, which may be of interest for control of glucose metabolism and insulin sensitivity. Probiotics also reduced hepatic glycogen and glutamine and adrenal ascorbate with inferred effects on energy homeostasis, antioxidation, and steroidogenesis. These studies show the breadth and the depth of gut microbiome modulations of host biochemistry and reveal that major mammalian metabolic processes are under symbiotic homeostatic control.
Journal of Proteome Research 05/2009; 8(4):2090-105. · 5.11 Impact Factor
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ABSTRACT: Fructooligosaccharides (FOS) are considered prebiotics because of their ability to promote growth of specific beneficial gut bacteria, such as bifidobacteria. Some studies reported potential immune-modulating properties. The aim of this study was to investigate the effect of FOS:inulin mix on murine response to Salmonella vaccine and evaluate the relevance toward protection against Salmonella infection. Balb/c mice were fed a diet containing 5% FOS:inulin mix or a control diet 1 wk before oral immunization with a suboptimal dose of live attenuated Salmonella typhimurium vaccine. Four weeks after vaccination, mice were infected with LD100 of virulent S. typhimurium. Specific blood Salmonella immunoglobulin G and fecal immunoglobulin A significantly increased in mice fed the diet containing prebiotics compared with control mice 4 wk postimmunization. Peritoneal macrophage phagocytic activity also significantly increased in FOS:inulin-fed mice at 1 wk postimmunization compared with control mice. No detectable effects were observed on the percentage of lymphoid cell subsets in the spleen. However, production of cytokines, interferon-gamma, interleukin-12, and tumor necrosis factor alpha, was numerically increased in spleen cell cultures stimulated with mitogens from FOS:inulin-fed mice 1 and 4 wk postimmunization. Salmonella translocation to lymphoid organs was not affected by feeding FOS:inulin. However, the improved response to Salmonella vaccine was concomitant with an increase in the survival rate of FOS:inulin-fed mice upon challenge with virulent Salmonella. No detectable effects were observed on the composition or the metabolic activity of the microbiota. Overall, the data suggest that a diet supplemented with FOS:inulin mix stimulates mucosal immunity and seems to improve efficacy of an oral vaccine.
Journal of Nutrition 02/2008; 138(1):123-9. · 3.92 Impact Factor
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ABSTRACT: The intestinal mucus layer and endogenous microbiota are strongly intertwined and this contributes to the maintenance of the epithelial barrier and ultimately of gut homeostasis. To understand the molecular foundations of such relationship, we investigated if the nature of the microbiota transcriptionally regulates mucus layer composition in vivo. We found that the expression of mucins 1 to 4 and trefoil factor 3 was down-regulated in the ileum and colon of conventional and reconventionalized mice compared with germ-free animals. Conversely, very limited colon-restricted changes in transmembrane mucins were detected in mice colonized with human adult or baby microbiota. Moreover, by microarray analysis, the murine endogenous microbiota was found to modulate genes putatively involved in mucin secretion. These findings show that a well-established microbial community participates in the regulation of the gut mucus layer and that its composition and adequacy to the host are key factors in this process.
Genomics 02/2008; 91(1):70-7. · 3.02 Impact Factor
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Francois-Pierre J Martin,
Yulan Wang,
Norbert Sprenger,
Ivan K S Yap,
Serge Rezzi,
Ziad Ramadan,
Emma Peré-Trepat,
Florence Rochat, Christine Cherbut,
Peter van Bladeren,
Laurent B Fay,
Sunil Kochhar,
John C Lindon,
Elaine Holmes,
Jeremy K Nicholson
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ABSTRACT: Gut microbiome-host metabolic interactions affect human health and can be modified by probiotic and prebiotic supplementation. Here, we have assessed the effects of consumption of a combination of probiotics (Lactobacillus paracasei or L. rhamnosus) and two galactosyl-oligosaccharide prebiotics on the symbiotic microbiome-mammalian supersystem using integrative metabolic profiling and modeling of multiple compartments in germ-free mice inoculated with a model of human baby microbiota. We have shown specific impacts of two prebiotics on the microbial populations of HBM mice when co-administered with two probiotics. We observed an increase in the populations of Bifidobacterium longum and B. breve, and a reduction in Clostridium perfringens, which were more marked when combining prebiotics with L. rhamnosus. In turn, these microbial effects were associated with modulation of a range of host metabolic pathways observed via changes in lipid profiles, gluconeogenesis, and amino-acid and methylamine metabolism associated to fermentation of carbohydrates by different bacterial strains. These results provide evidence for the potential use of prebiotics for beneficially modifying the gut microbial balance as well as host energy and lipid homeostasis.
Molecular Systems Biology 01/2008; 4:205. · 8.63 Impact Factor
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ABSTRACT: Psychological stress during the neonatal period results in intestinal barrier dysfunction and growth alterations later in life. We aimed to restore impaired barrier function and growth rate by a nutritional intervention.
Male rat pups (n = 84) were assigned to 1 of 2 rearing conditions from postnatal day (PND) 2 to PND14: S, separated 3 h/d from their mothers, or H, 15 min/d handled controls. From PND15 to PND35, rats received a control diet or a similar diet adapted to contain arachidonic and docosahexaenoic acids, galacto- and fructo-oligosaccharides and Lactobacillus paracasei NCC2461.
Maternal separation had only a minor impact on the measured gut barrier parameters at PND15, whereas it severely affected them at PND35. At this age, intestinal permeability to macromolecules was higher, mucin content in small intestinal tissues was lower and microbiota composition was altered in S compared with H animals. Feeding the adapted diet normalized the intestinal permeability, although it did not restore intestinal mucin content or microbiota. In addition, the adapted diet improved the growth rate recovery of the S animals after weaning and resulted in increased villus length in small intestine.
Our results suggest that an adapted diet containing specific long-chain polyunsaturated fatty acids, prebiotics and probiotics can revert the negative imprinting of neonatal stress on both intestinal barrier function and growth.
Journal of Pediatric Gastroenterology and Nutrition 08/2006; 43(1):16-24. · 2.30 Impact Factor
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ABSTRACT: The mucus layer covering the epithelium is one of the main lines of defense of the colonic barrier. Both mucus gel and mucin expressions are altered during colonic inflammation and could be involved in epithelial repair. We postulated that modulating colonic mucus and mucins by probiotic supplementation could contribute to healing inflammatory mucosa. Our aim in this study was to determine whether probiotics could repair dextran-sodium sulfate (DSS)-induced chronic colitis in mice, and whether modifications of the colonic mucins could be involved. For that purpose, the VSL#3 probiotic mixture of 8 lactic acid bacteria probiotic strains was administered daily for 2 wk to mice with a mucosa impaired by a mild DSS treatment, and to mice with a normal mucosa. Probiotic strains survived in the gastrointestinal tract, increased the cecal concentrations of bifidobacteria, and modified cecal microflora metabolic activity in both DSS-treated and healthy mice. However, probiotic supplementation did not reverse the inflammation induced by DSS at either the macroscopic or histological level. Concurrently, probiotics did not modify the colonic mucus barrier, in terms of either mucin gene expression or adherent mucus layer thickness. In conclusion, the modification of microflora by supplementation with the VSL#3 probiotic mixture did not help to repair the colonic barrier breakdown caused by DSS treatment. The potential healing roles of mucins were neither confirmed nor invalidated by this study.
Journal of Nutrition 01/2006; 135(12):2753-61. · 3.92 Impact Factor
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ABSTRACT: The postnatal maturation of the gut, partially modulated by bacterial colonization, ends up in the establishment of an efficient barrier to luminal antigens and bacteria. The use of broad-spectrum antibiotics in pediatric practices alters the gut bacterial colonization and, consequently, may impair the maturation of the gut barrier function. To test this hypothesis, suckling Sprague-Dawley rats received a daily intragastric gavage of antibiotic (Clamoxyl; an amoxicillin-based commercial preparation) or saline solution from postnatal day 7 (d7) until d17 or d21. Luminal microbiota composition and global gene expression profile were analyzed on samples from small intestine and colon of each group. The treatment with Clamoxyl resulted in the almost-complete eradication of Lactobacillus in the whole intestine and in a drastic reduction of colonic total aerobic and anaerobic bacteria, in particular Enterobacteriacae and Enterococcus. The global gene expression analysis revealed that Clamoxyl affects the maturation process of 249 and 149 Affymetrix probe sets in the proximal and distal small intestine, respectively, and 163 probe sets in the colon. The expression of genes coding for Paneth cell products (defensins, matrilysin, and phospholipase A2) was significantly downregulated by the Clamoxyl treatment. A significant downregulation of major histocompatibility complex (MHC) class Ib and II genes, involved in antigen presentation, was also observed. Conversely, mast cell proteases expression was upregulated. These results suggest that early treatment with a large-spectrum antibiotic deeply affects the gut barrier function at the suckling-weaning interface, a period during which the gut is challenged by an array of novel food-borne antigens.
Physiological Genomics 11/2005; 23(2):235-45. · 2.73 Impact Factor
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ABSTRACT: Chronic nutritional disorders such as protein malnutrition are associated with delayed gastric emptying and increased postprandial cholecystokinin (CCK) levels. This study investigated the mechanisms involved in gastric emptying adaptation to low-protein diet. Two groups of 12 rats were adapted to a low-protein (LPD) or standard diet (SD) for 3 weeks. As compared to rats fed a SD, in rats adapted to a LPD gastric emptying was delayed, whereas postprandial CCK levels were increased. LPD enhanced antral muscle contractile response to CCK and cerulein without altering response to acetylcholine. This increased contractility was associated with up-regulation of CCK-A receptor mRNA levels in antral muscle. Our data suggest that modulation of gastric emptying after adaptation to a low-protein diet involves up-regulation of both CCK-A receptors and CCK-induced contraction of antral smooth muscle.
Peptides 01/2004; 24(12):1929-34. · 2.43 Impact Factor
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ABSTRACT: Leptin, a protein with a cytokine-like structure, is produced predominantly by adipocytes. It appears to play a key role in immune responses by increasing the secretion of Th1 and pro-inflammatory cytokines. As fat-wrapping is a characteristic feature of Crohn's disease (CD), and as increased leptin levels have been reported in animal models of intestinal inflammation, this study investigated whether mesenteric adipose tissue could be a source of leptin in human inflammatory bowel disease (IBD).
To quantify the expression of leptin mRNA in mesenteric adipose tissue of patients with CD or ulcerative colitis (UC).
Specimens were obtained from mesenteric white adipose tissue close to healthy and inflammatory small intestine and/or colon in patients with CD or UC and, for controls, from apparently healthy mesentery of patients operated for carcinoma of the right colon. The expression of leptin mRNA was assessed by reverse transcription-competitive polymerase chain reaction.
Leptin mRNA levels were significantly higher in mesenteric adipose tissue of CD and UC patients than in controls (P<0.05). In CD and UC, concentrations were not significantly different in mesenteric fat specimens, whether contiguous to macroscopically normal or grossly abnormal intestine.
This study provides the first evidence of a novel abnormality of the mesentery of patients with IBD. Overexpression of leptin mRNA in mesenteric adipose tissue may contribute to (a) the inflammatory process, (b) enhancement of mesenteric TNF alpha expression in CD (as recently reported), and/or (c) the anorexia frequently reported during flares of IBD.
Gastroentérologie Clinique et Biologique 12/2003; 27(11):987-91. · 0.80 Impact Factor
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British Journal Of Nutrition 03/2003; 89(2):283-4; discussion 285-6. · 3.01 Impact Factor
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Christine Cherbut
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ABSTRACT: Short-chain fatty acids (SCFA) affect local and remote motility of the gastrointestinal tract by mechanisms that are not completely understood. In the large intestine where they are produced, they inhibit peristaltic activity and may stimulate tonic activity. When present in the terminal ileum as a result of reflux of colon contents, they elicit propulsive contractions. These local motor effects could involve a neuro-hormonal sensory mechanism located in the mucosa of the terminal ileum and proximal colon. Finally, through a humoral pathway probably involving polypeptide YY release, ileal and colonic SCFA modify upper motility by inducing relaxation of the proximal stomach and lower oesophageal sphincter and reducing gastric emptying. One characteristic feature of the SCFA effects is the dose-dependency of the gastrointestinal motor responses. Indeed, the effects occur only below or above a threshold of SCFA concentration in lumen contents. One putative physiological role of the motor effects of SCFA might be to maintain the physico-chemical balance of the lumen environment in the terminal ileum and proximal colon. Another role might be to co-regulate motility of the upper intestine. The clinical relevance of these effects is unclear. However, some recent findings suggest that excessive SCFA concentrations might induce adverse effects on gastrointestinal and colonic motility and sensitivity in certain diseases such as inflammatory bowel disease and gastro-oesophageal reflux disease.
Proceedings of The Nutrition Society 03/2003; 62(1):95-9. · 2.77 Impact Factor
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ABSTRACT: Short-chain fatty acids (SCFA), particularly butyrate, were shown to regulate cell proliferation in vitro and in vivo. Indeed, butyrate is the major fuel for colonic epithelial cells, and it can influence cell proliferation through the release of growth factors or gastrointestinal peptides such as gastrin, or through modulation of mucosal blood flow. Lastly, SCFA can act directly on genes regulating cell proliferation, and butyrate is the main SCFA to display such an effect. Butyrate inhibits histone deacetylase, which will allow histone hyperacetylation. Such hyperacetylation leads to transcription of several genes, including p21/Cip1. Moreover, it will allow cyclin D3 hyper-expression by inhibiting its degradation. The induction of the cyclin-dependent kinase inhibitory protein p21/Cip1 accounts for cell arrest in the G1 phase of the cell cycle. However, in the absence of p21 other mechanisms are initiated, leading to inhibition of cell proliferation.
Proceedings of The Nutrition Society 03/2003; 62(1):101-6. · 2.77 Impact Factor
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ABSTRACT: 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.
Journal of Nutrition 01/2003; 133(1):21-7. · 3.92 Impact Factor
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ABSTRACT: Peptide YY (PYY) is involved in the regulation of several gastro-intestinal functions, including motility. The aims of the present study were (i) to characterize the effects of PYY on smooth muscle strips obtained from the different gastro-intestinal segments in rats and in humans and (ii) to realize a map of the Y receptors expression. Contractions of strips were recorded under isometric conditions, using PYY and acetylcholine as control. We observed that PYY induced a contraction of muscle strips from rat proximal colon, but displayed no effect on other gut segments. Using RT-PCR, mRNA encoding the Y1 and Y4 receptors were detected in muscle strips depending on the segment. In humans, the muscle preparations responded to ACh but not to PYY. Moreover, only Y2 receptor mRNA was found in the ileum and the left colon, but not in other segments. Our study shows the heterogeneity in the expression of Y receptors along the gastro-intestinal tract, and reveals great discrepancies between rats and humans both concerning the expression of Y receptor, and the response of smooth muscle strips to PYY.
Peptides 11/2002; 23(10):1765-71. · 2.43 Impact Factor
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ABSTRACT: Epidermal growth factor peptide binding was analyzed on primary cultures of colonic cells and along crypts by fluorescent laser-scanning confocal microscopy, using a three-dimensional image analysis software (Quant3D, Linux/Unix). Structural, proliferative units from primary cultures grown in rotating bioreactor for 41 d were arranged according to a tubular symmetry or on a parallelepiped sheet. Mean width, height, and depth of 23 tissue-like masses (+/- standard error) were 125 microm (+/-16), 152 microm (+/-23), and 29 microm (+/-3), respectively. Mean density of nuclei in tissue-like masses, expressed as the number of nuclei per cubic millimeter (+/- standard error of the mean), was 1.8 x 10(5) (+/-0.7 x 10(5)) nuclei per cubic millimeter, which corresponded to a density that was five to six times lower than that estimated for the colonic crypt isolated by chelation. Spots of high epidermal growth factor (EGF) peptide binding that corresponded to microlesions in crypt monolayers or to active colonization of microcarriers by epithelial and stromal cells in tissue-like masses were observed. The relative intensities of EGF peptide binding that were obtained below cell position 8 on crypts were very homogeneous and were representative of the profile obtained with crypts isolated from adult rats adapted to a normal diet and used to develop primary cultures of colonocytes in our laboratory. A microscopic multidimensional analytic system to record the expression profiles of biomarkers along intestinal tissues should enhance the use of primary cultures of colonocytes for in vitro testing of new food products.
In Vitro Cellular & Developmental Biology - Animal 10/2002; 38(8):436-9. · 1.31 Impact Factor
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ABSTRACT: This study evaluated the effect of digestion on the chemical and physicochemical characteristics of dietary fibre and on its behaviour during fermentation. Three dietary fibre sources (wheat bran, barley bran and beet fibre) were recovered from ileal cannulated pigs after in vivo digestion and prepared by in vitro enzymatic treatment simulating digestion. Raw substrates and fibre residues were analysed for their chemical and physicochemical properties as well as their potential fermentation by human colonic bacteria. In vitro and in vivo treatments led to insoluble residues, enriched in cell wall polysaccharides, with similar cell wall sugar composition and physicochemical properties. Degradations of cell wall polysaccharides with losses of sugar residues occurred mainly after in vivo digestion, especially for pectins from beet fibre and β-glucans from barley bran. Solubilisation of β-glucans removed highly fermentable substrates for further fermentation. For beet fibre, removal of pectins led to increased hydration properties and faster fermentation of cell-wall polysaccharides. Enzymatic treatment simulated correctly the passage of fibre through the digestive tract, modifying the cell-wall matrix and predisposing the fibre to further fermentation. © 1998 SCI.
Journal of the Science of Food and Agriculture 03/1999; 77(3):327 - 333. · 1.44 Impact Factor
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ABSTRACT: According to Burkitt's hypothesis, dietary fibres may protect against the development of colorectal cancer. In rats, studies have shown that only butyrate-producing fibres are protective. In parallel, in humans, non-steroidal anti-inflammatory drugs, which target cyclooxygenases, have been shown to display a protective effect against colorectal cancer. Among them, COX-2-selective inhibitors which present less side effects than non-selective agents, are promising as chemopreventive agents. Our aim was to analyse the effect of an association between butyrate-producing fibres and the COX-2 inhibitor on the development of aberrant crypt foci (ACF) in rats. Fisher F344 rats were fed with (1) a standard low fibre control diet; (2) the standard diet supplemented with 1500 ppm celecoxib; (3) a diet supplemented with 6% fructo-oligosaccharide (FOS); and (4) a diet with both celecoxib and FOS. Three weeks later, the rats were injected twice with azoxymethane and the number of ACF was determined 15 weeks later. In the control group, 43.8 +/- 6.4 ACF were found. This number was not significantly modified by the addition of FOS or celecoxib alone to the diet. However, the association of FOS and celecoxib resulted in a 61% reduction in the number of ACF (P < 0.01). The number of aberrant crypt per foci was also reduced. Thus, although no significant effect of celecoxib or FOS alone was identified, the association of butyrate-producing fibre and celecoxib was effective in preventing the development of ACF. This preliminary study argues for a strong protective effect of such an association which deserves further studies.
Reproduction Nutrition Development 43(4):347-56. · 1.90 Impact Factor
