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Short-chain Fatty Acids (short-chain + fatty_acid)
Selected AbstractsThe effect of butyric acid on adhesion molecule expression by human gingival epithelial cellsJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2008S. Takigawa Background and Objective:, Short-chain fatty acids, such as butyric acid, are detected in periodontal pockets and are thought to be involved in the initiation and progression of periodontal disease. In the present study, we examined the effects of butyric acid on adhesion molecule expression by human gingival epithelial cells. Material and methods:, The human gingival carcinoma cell line, Ca9-22, was cultured in media that contained different concentrations of butyric acid. Results:, Cell numbers were significantly decreased in a dose-dependent manner by butyric acid at concentrations of , 0.2 mm. The expression of intercellular adhesion molecule-1 mRNA was significantly increased 6 h after stimulation. By contrast, the expression levels of integrins ,6 and ,4 were decreased. Similar results were obtained by flow cytometry. Conclusion:, The results of the present study indicate that butyric acid alters the expression of adhesion molecules by Ca9-22 cells. The elucidation of the mechanism of action of butyric acid on the periodontium may help to clarify several aspects of the onset and progression of periodontal disease. [source] Rapid determination of short-chain fatty acids in colonic contents and faeces of humans and rats by acidified water-extraction and direct-injection gas chromatographyBIOMEDICAL CHROMATOGRAPHY, Issue 8 2006Guohua Zhao Abstract Short-chain fatty acids (SCFAs) have attracted much attention recently because of their positive physiological effects. In this work, a rapid and reliable gas chromatographic method for determination of eight SCFAs, in colonic and faecal samples from rats and humans has been developed and validated. The methodology involves extraction of the SCFAs in water before a direct injection procedure on a FFAP capillary column. A stock standard solution containing acetic acid, propionic acid, n -butyric acid, i -butyric acid, n -valeric acid, i -valeric acid, n -caproic acid and n -heptanoic acid was prepared and used. A high line-arity (r2 > 0.9990), low quantification limit (2.38,30.14 µm) and high recovery for most acids were obtained. Acidification of faecal samples was found to be crucial for quantitative determination of the SCFAs, and adjustment of pH to 2,3 was regarded as necessary. Glass wool inserted in the glass liner of the injection port proved effective in preventing the contamination of the column by non-volatiles, and 12% formic acid reduced the ghost peak that appeared gradually after several injections. After validation, the methodology was applied on two faecal samples from rats fed diets containing different amount of dietary fibre and one faecal sample from human fed a normal diet to test the accuracy of the developed method. Copyright © 2005 John Wiley & Sons, Ltd. [source] Review article: prebiotics in the gastrointestinal tractALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2006S. MACFARLANE Summary Background Prebiotics are short-chain carbohydrates that alter the composition, or metabolism, of the gut microbiota in a beneficial manner. It is therefore expected that prebiotics will improve health in a way similar to probiotics, whilst at the same time being cheaper, and carrying less risk and being easier to incorporate into the diet than probiotics. Aim To review published evidence for prebiotic effects on gut function and human health. Methods We searched the Science Citation Index with the terms prebiotic, microbiota, gut bacteria, large intestine, mucosa, bowel habit, constipation, diarrhoea, inflammatory bowel disease, Crohn's disease, ulcerative colitis, pouchitis, calcium and cancer, focussing principally on studies in humans and reports in the English language. Search of the Cochrane Library did not identify any clinical study or meta-analysis on this topic. Results Three prebiotics, oligofructose, galacto-oligosaccharides and lactulose, clearly alter the balance of the large bowel microbiota by increasing bifidobacteria and Lactobacillus numbers. These carbohydrates are fermented and give rise to short-chain fatty acid and intestinal gas; however, effects on bowel habit are relatively small. Randomized-controlled trials of their effect in a clinical context are few, although animal studies show anti-inflammatory effects in inflammatory bowel disease, while calcium absorption is increased. Conclusions It is still early days for prebiotics, but they offer the potential to modify the gut microbial balance in such a way as to bring direct health benefits cheaply and safely. [source] Molecular weight of guar gum affects short-chain fatty acid profile in model intestinal fermentationMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 10 2006Maria L. Stewart Abstract Dietary fiber exerts many beneficial physiological effects; however, not all types of dietary fiber display the same effects. Partially hydrolyzed guar gum (PHGG), a lower molecular weight form of guar gum, is more easily incorporated into food, but may have less pronounced physiological effects than the native form. The aim of this study was to identify differences in intestinal fermentability based on the molecular weight of guar gum. Guar gum of four molecular masses (15, 20, 400, and 1100 kDa) was fermented using a batch in vitro fermentation system. Human fecal inoculum was the source of microbes. The 400-kDa fraction produced the greatest concentrations of total short-chain fatty acid (SCFA) at 8 h and the highest amounts of butyrate at 24 h. At 24 h, the 400-kDa fraction produced more total SCFA and propionate than the 15 kDa, but was not different than 20 kDa or 1100 kDa fractions. The molecular weight of guar gum was positively correlated with acetate production and negatively correlated with propionate production. This study concludes that 400-kDa guar gum may be optimal for intestinal fermentability. In conclusion, the molecular weight of guar gum affects in vitro fermentability and should be considered when adding to a food or beverage. [source] The concentrations of short-chain fatty acids and other microflora-associated characteristics in faeces from children with newly diagnosed Type 1 diabetes and control children and their family membersDIABETIC MEDICINE, Issue 1 2004U. Samuelsson Abstract Aims The gut flora is quantitatively the most important source of microbial stimulation and may provide a primary signal in the maturation of the immune system. We compared the microflora-associated characteristics (MACs) in 22 children with newly diagnosed diabetes, 27 healthy controls, and their family members to see if there were differences between the children and if there was a familial pattern. Methods The MACs were assessed by determining the concentrations of eight short-chain fatty acids (SCFA), mucin, urobilin, b-aspartylglycine, coprastanol and faecal tryptic activity (FTA). Results There were no statistically significant differences between the concentrations of SCFA in the diabetes and control children. Members of families with a diabetic child had a higher concentration of acetic acid (P < 0.02) and lower concentrations of several other SCFAs than control families (P < 0.05,0.02). The other MACs showed no differences between the children or between the two family groups. Conclusion In this pilot study we saw no differences in the MACs between children with diabetes and their controls. There were, however, some differences between the family members of diabetic children and controls that may indicate a familial pattern regarding the production of SCFAs by the gut flora. The role of the gut flora in relation to the risk of developing Type 1 diabetes needs to be analysed in larger and/or prospective studies. [source] Sulfatide with short fatty acid dominates in astrocytes and neuronsFEBS JOURNAL, Issue 8 2006Giorgis Isaac Glycosphingolipids are located in cell membranes and the brain is especially enriched. We speculated that the subcellular location of glycosphingolipids depends on their fatty acid chain length because their sugar residues are constant, whereas fatty acid chain length can vary within the same molecule. To test this hypothesis we analysed the glycosphingolipid sulfatide, which is highly abundant in myelin and has mostly long fatty acids. We used a negative ion electrospray tandem mass spectrometry precursor ion scan to analyse the molecular species of sulfatide in cultured astrocytes and a mouse model of the human disease metachromatic leukodystrophy. In these arylsulfatase A (ASA)-deficient mice sulfatide accumulates intracellularly in neurons and astrocytes. Immunocytochemistry was also performed on cultured astrocytes and analysed using confocal laser scanning microscopy. Analyses of the molecular species showed that cultured astrocytes contained sulfatide with a predominance of stearic acid (C18), which was located in large intracellular vesicles throughout the cell body and along the processes. The same was seen in ASA-deficient mice, which accumulated a higher proportion (15 mol% compared with 8 mol% in control mice) of sulfatide with stearic acid. We conclude that the major fatty acid composition of sulfatide differs between white and grey matter, with neurons and astrocytes containing mostly short-chain fatty acids with an emphasis on stearic acid. Based on our results, we speculate that the fatty acid chain length of sulfatide might determine its intracellular (short chain) or extracellular (long chain) location and thereby its functions. [source] Mechanisms and modulation of intestinal epithelial repairINFLAMMATORY BOWEL DISEASES, Issue 1 2001Dr. Axel U. Dignass Abstract The mucosal epithelium of the alimentary tract represents a crucial barrier to a broad spectrum of noxious and immunogenic substances within the intestinal lumen. An impairment of the integrity of the mucosal epithelial barrier is observed in the course of various intestinal disorders including inflammatory bowel diseases (IBD), celiac disease, intestinal infections, and various other diseases. Furthermore, even under physiologic conditions temporary damage of the epithelial surface mucosa may be caused by proteases, residential flora, dietary compounds, or other factors. Generally, the integrity of the intestinal mucosal surface barrier is rapidly reestablished even after extensive destruction because of an enormous regenerative capability of the mucosal surface epithelium. Rapid resealing of the surface epithelium is accomplished by epithelial cell migration, also termed epithelial restitution, epithelial cell proliferation, and differentiation. Healing of the intestinal surface epithelium is regulated by a complex network of highly divergent factors, among them a broad spectrum of structurally distinct regulatory peptides that have been identified within the mucosa of the intestinal tract. These regulatory peptides, conventionally designated as growth factors and cytokines, play an essential role in regulating differential epithelial cell functions to preserve normal homeostasis and integrity of the intestinal mucosa. In addition, a number of other peptide molecules such as extracellular matrix factors and blood clotting factors, and also nonpeptide molecules including phospholipids, short-chain fatty acids, adenine nucleotides, trace elements, and pharmacological agents, have been demonstrated to modulate intestinal epithelial repair mechanisms. Some of these molecules may be released by platelets, adjacent stromal cells, inflammatory cells, or injured epithelial and nonepithelial cells and may play an important role in the modulation of intestinal injury. Repeated damage and injury of the intestinal surface are key features of various intestinal disorders including IBD and require constant repair of the epithelium. Enhancement of intestinal repair mechanisms by regulatory peptides or other modulatory factors may provide future approaches for the treatment of diseases that are characterized by injuries of the epithelial surface. [source] Nutritional and therapeutic value of fermented caprine milkINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2010ANAC, VEDRAN SLA Caprine milk is a nutritional and therapeutic food. The unique and beneficial characteristics of caprine milk that are superior to bovine milk include: better digestibility; greater buffering capacity; fat globules that are smaller in diameter and better distributed in the milk emulsion; higher content of short-chain fatty acids in the milk fat; higher content of zinc, iron and magnesium; stronger lactoperoxidase (antimicrobial) system as well as better immunological and antibacterial characteristics. The larger amounts of some minerals, such as calcium, zinc and magnesium, in caprine milk may influence the growth of lactic acid bacteria since they are a normal part of some enzymatic complexes involved in lactose fermentation. The higher whey protein content could also be significant because Lactobacillus acidophilus and bifidobacteria grow better in the presence of higher levels of some amino acids (valine, glycine, hystidine). The use of caprine and ovine milk in cheesemaking is well known, but the production of fermented caprine milk via probiotics has not yet been developed, although many studies have highlighted the requirements for production of that kind of healthy food. During fermentation caprine milk loses its characteristic ,goaty' taste, which is unacceptable to many consumers. Moreover, the nutritive value of caprine milk increases during fermentation. The rise in the number of goat farms in Croatia has created the need to find other products that can be produced using caprine milk. According to the present situation in Croatia, there is no real possibility of producing fermented caprine milk for the global market, but many studies of fermented caprine milk have been performed. [source] ORIGINAL ARTICLE: Application of soybean meal, soy protein concentrate and isolate differing in , -galactosides content to low- and high-fibre diets in growing turkeysJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010Z. Zdu, czyk Summary The aim of this experiment was to investigate the physiological and growth response of young turkeys (up to 8 weeks of age) to dietary replacement of soybean meal (SBM) by soy protein concentrate (PC) or protein isolate (PI). This replacement resulted in a differentiated dietary concentration of , -galactosides of over 2.5% in the SBM diet, approximately 2% with a mixture SBM and PC, 1% with a PC diet and 0.1% with a PI diet. Each treatment was applied in two ways: with lower (3.5%) or higher (5.3%) dietary crude fibre content, made by supplementation with soybean hulls. The highest and lowest body weight of turkeys was recorded both after the first and second 4-week half of the study in the PC and PI-type diets respectively. A gradual withdrawal of , -galactosides from a diet was accompanied by a decline in ileal tissue mass, ileal viscosity and activity of endogenous maltase (the latter was found to be significant at 4 weeks of age). At the same time, two-way anova revealed that an elevated level of crude fibre (HF treatment) caused an increase in ileal tissue mass (p < 0.05 after 4 weeks of feeding) as well as a decrease in activity level of intestinal sucrase and maltase. The presence of raffinose family oligosaccharides in a diet, in contrast to dietary crude fibre level, significantly affected the caecal metabolism. The rate of bacterial production of short-chain fatty acids in the caeca was distinctly diminished by dietary withdrawal of , -galactosides. In conclusion, the soy protein concentrate, in contrast to the protein isolate preparation, exerted positive effects on the turkeys' growth and gastrointestinal tract physiology and should be considered as an effective SBM substitute. [source] Effects of hay intake and feeding sequence on variables in faeces and faecal water (dry matter, pH value, organic acids, ammonia, buffering capacity) of horsesJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2004A. Zeyner Summary To investigate effects of hay intake and feeding sequence on indicators of the microbial activity within the hindgut, six horses were fed 1.00 kg oats plus 0.50, 0.67, 0.83 or 1.00 kg hay/100 kg body weight (BW) × day, each for 14 days. Oats was offered either 30 min prior to hay (OA) or in the reversed sequence (HA) in a 2 × 8-week crossover design. Because typically exercised horses should be subjected to the study, faeces was used as substrate. Faecal dry matter (DM), the faecal waters' short-chain fatty acids (SCFA, in mmol/l) and molar percentages (mol%) of propionate and iso-butyrate were highest with OA (p < 0.01). Acetate mol%, acetate,propionate quotient (A/P) and buffering capacities 1 and 2 (BC1: current pH to pH 6; BC2: pH 6 to 5) of the faecal water were highest with HA (p < 0.01). While the hay intake rose, faecal pH, acetate mol%, A/P, BC1 and BC2 (the latter with HA only) increased (p < 0.05), but DM, SCFA and propionate mol% declined (p < 0.05). The hay-induced rise in A/P and BC1 was much higher with HA than with OA. l -Lactate and ammonia were unaffected by the feeding sequence and hay intake. In conclusion, hay intake and feeding sequence influence the microbial activity within the hindgut, although the concentrate level remains consistent. In horse rations with 1.00 kg oats/100 kg BW × day amounts of at least 0.83 kg hay/100 kg BW × day and offering the hay first seem to have the potency to protect the hindgut content from acidification. Behavioural abnormality was not observed any longer first with 1.00 kg hay/100 kg BW × day. [source] Modulation of Na+ transport across isolated rumen epithelium by short-chain fatty acids in hay- and concentrate-fed sheepJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 11-12 2003S. K. Uppal Summary The effect of increasing concentrations of short-chain fatty acids [SCFA; mixture of the Na+ salts of acetic acid (62.5%), propionic acid (25.0%) and of butyric acid (12.5%)] on Na+ transport of sheep rumen epithelium was studied in vitro. The conventional Ussing chamber method was used for measuring Na+ transport rates (22Na+), short-circuit current (Isc) and tissue conductance (GT) of isolated rumen epithelium. SCFA in the buffer solution on the mucosal side caused a linear increase of Jnet Na+ from 1.14, to 1.22, 1.78 and 2.50 ,eq/cm2/h in hay-fed sheep at 0, 15, 40 and 80 mmol/l SCFA, respectively. In a second study, the effect of higher SCFA concentrations [0 (control), 80, 100 and 120 mmol/l] was investigated with epithelia from two groups of sheep. One group was subjected to hay ad libitum, whereas the other received concentrate feed (800 g/day in equal portions at 7.00 am and 3.00 pm) and hay ad libitum. Epithelia from concentrate-fed sheep again showed a significant (p < 0.05) and linear increase in Jnet Na+ at 80, 100 and 120 mmol/l. However, in hay-fed sheep, the difference in increase among 80, 100 and 120 mmol/l SCFA was not significant, indicating that, above 80 mmol/l SCFA Jms and Jnet exhibit saturation. Moreover, Na+ fluxes (Jms and Jnet) were generally higher in concentrate-fed than in hay-fed sheep at all SCFA concentrations and significant differences were observed at 100 and 120 mmol/l SCFA. The obtained results confirm the effect of SCFA on Na+ transport and are in agreement with studies regarding feeding regimes and electrolyte transport in the rumen. The important new observation is the increase of Na+ transport in concentrate-fed sheep even at high concentrations of SCFA (100 and 120 mmol/l). The enhanced activity of the Na+/H+ exchanger at these SCFA concentrations supports the assumption that the capacity for regulating the intracellular pH by extrusion of protons is increased, suggesting an adaptation in concentrate-fed sheep. This adaptation could prevent possible disturbances of epithelial functions (transport and barrier) under conditions of increased SCFA absorption. [source] The role of probiotics and prebiotics in the management of diarrhoea associated with enteral tube feedingJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 6 2001K. Whelan Introduction Diarrhoea is a common and serious complication of enteral tube feeding, and has a range of aetiologies. Manipulation of the colonic microflora may reduce the incidence of enteral tube feeding diarrhoea via suppression of enteropathogens and production of short-chain fatty acids. Probiotics and prebiotics are commonly used during enteral tube feeding to manipulate the colonic microflora; however, their efficacy is as yet uncertain. Methods English-language studies investigating the pathogenesis of enteral tube feeding diarrhoea and the use of probiotics and prebiotics were identified by searching the electronic databases CINAHL, EMBASE and MEDLINE from 1980 to 2001. The bibliographies of articles obtained were searched manually. Results Only two prospective, randomized, double-blind, placebo-controlled trials have investigated the effect of a probiotic on enteral tube feeding diarrhoea; however, results are conflicting. No prospective, randomized, double-blind, placebo-controlled studies have specifically addressed the effect of a prebiotic on the incidence of enteral tube feeding diarrhoea. Conclusion Theoretically, probiotics and prebiotics may be of benefit in prophylaxis against enteral tube feeding diarrhoea; however, there is currently insufficient evidence to support their routine use. Prospective, randomised, double-blind, placebo-controlled studies investigating their effect on diarrhoea are required. These observations are discussed with reference to the current literature. [source] Long-term effects on the digestive tract of feeding large amounts of resistant starch: A study in pigsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2007Daniel Martínez-Puig Abstract The present study aimed to assess the digestive consequences of the long-term intake of two starches providing different amounts of resistant starch. Growing pigs were used as the animal model and meal-fed for 14 weeks on a diet containing a high amount of either raw potato starch (RPS) or corn starch (CS). Digestive adaptation was chronologically evaluated by measuring organic matter (OM), crude protein (CP), neutral detergent fibre (NDF) and starch digestibility. After 97 days, whole-tract digestibility of OM, CP and NDF was lower for RPS- compared to CS-fed pigs, whereas no differences were observed in faecal starch digestibility. In contrast, starch digestibility was reduced in the proximal compartments (ileum, caecum and proximal colon) of animals fed the RPS diet. The concentration of short-chain fatty acids (SCFAs; P < 0.05), and purine bases (PBs; P < 0.01) was also higher in distal colon and rectum of animals fed the RPS diet. Changes in bacterial community structure (dendogram analyses) were seen in the rectum. Biodiversity tends to increase more in RPS compared to CS fed animals (34.1 vs. 28.8; P = 0.07). Among SCFAs, the proportion of butyrate was two-fold higher in proximal colon digesta of RPS compared to CS fed pigs (0.20 vs. 0.11; P < 0.05). Increased butyrate formation in the colon reduced the number of apoptosis per crypt in the proximal colonic mucosa (0.38 vs. 0.62; P < 0.05). RPS fermentation reduced indices associated with damage to intestinal epithelial cells, such as crypt cell hyperproliferation and magnesium excretion. Long-term ingestion of RPS induces pronounced changes of the digestive tract and their microflora, modifying mineral absorption and colonic morphology for which health benefits are likely to be associated. Copyright © 2007 Society of Chemical Industry [source] Role of circulating neurotoxins in the pathogenesis of hepatic encephalopathy: potential for improvement following their removal by liver assist devicesLIVER INTERNATIONAL, Issue 2003Roger F. Butterworth Abstract Both acute and chronic liver failure result in impaired cerebral function known as hepatic encephalopathy (HE). Evidence suggests that HE is the consequence of the accumulation in brain of neurotoxic and/or neuroactive substance including ammonia, manganese, aromatic amino acids, mercaptans, phenols, short-chain fatty acids, bilirubin and a variety of neuroactive medications prescribed as sedatives to patients with liver failure. Brain ammonia concentrations may attain levels in excess of 2 mm, concentrations which are known to adversely affect both excitatory and inhibitory neurotransmission as well as brain energy metabolism. Manganese exerts toxic effects on dopaminergic neurones. Prevention and treatment of HE continues to rely heavily on the reduction of circulating ammonia either by reduction of gut production using lactulose or antibiotics or by increasing its metabolism using l -ornithine- l -aspartate. No specific therapies have so far been designed to reduce circulating concentrations of other toxins. Liver assist devices offer a potential new approach to the reduction of circulating neurotoxins generated in liver failure. In this regard, the Molecular Absorbents Recirculating System (MARS) appears to offer distinct advantages over hepatocyte-based systems. [source] Legionella pneumophila couples fatty acid flux to microbial differentiation and virulenceMOLECULAR MICROBIOLOGY, Issue 5 2009Rachel L. Edwards Summary During its life cycle, Legionella pneumophila alternates between at least two phenotypes: a resilient, infectious form equipped for transmission and a replicative cell type that grows in amoebae and macrophages. Considering its versatility, we postulated that multiple cues regulate L. pneumophila differentiation. Beginning with a Biolog Phenotype MicroArray screen, we demonstrate that excess short-chain fatty acids (SCFAs) trigger replicative cells to cease growth and activate their panel of transmissive traits. To co-ordinate their response to SCFAs, L. pneumophila utilizes the LetA/LetS two-component system, but not phosphotransacetylase or acetyl kinase, two enzymes that generate high-energy phosphate intermediates. Instead, the stringent response enzyme SpoT appears to monitor fatty acid biosynthesis to govern transmission trait expression, as an altered distribution of acylated acyl carrier proteins correlated with the SpoT-dependent differentiation of cells treated with either excess SCFAs or the fatty acid biosynthesis inhibitors cerulenin and 5-(tetradecyloxy)-2-furoic acid. We postulate that, by exploiting the stringent response pathway to couple cellular differentiation to its metabolic state, L. pneumophila swiftly acclimates to stresses encountered in its host or the environment, thereby enhancing its overall fitness. [source] Profiling human gut bacterial metabolism and its kinetics using [U- 13C]glucose and NMRNMR IN BIOMEDICINE, Issue 1 2010Albert A. de Graaf Abstract This study introduces a stable-isotope metabolic approach employing [U- 13C]glucose that, as a novelty, allows selective profiling of the human intestinal microbial metabolic products of carbohydrate food components, as well as the measurement of the kinetics of their formation pathways, in a single experiment. A well-established, validated in vitro model of human intestinal fermentation was inoculated with standardized gastrointestinal microbiota from volunteers. After culture stabilization, [U- 13C]glucose was added as an isotopically labeled metabolic precursor. System lumen and dialysate samples were taken at regular intervals. Metabolite concentrations and isotopic labeling were determined by NMR, GC, and enzymatic methods. The main microbial metabolites were lactate, acetate, butyrate, formate, ethanol, and glycerol. They together accounted for a 13C recovery rate as high as 91.2%. Using an NMR chemical shift prediction approach, several minor products that showed 13C incorporation were identified as organic acids, amino acids, and various alcohols. Using computer modeling of the 12C contents and 13C labeling kinetics, the metabolic fluxes in the gut microbial pathways for synthesis of lactate, formate, acetate, and butyrate were determined separately for glucose and unlabeled background substrates. This novel approach enables the study of the modulation of human intestinal function by single nutrients, providing a new rational basis for achieving control of the short-chain fatty acids profile by manipulating substrate and microbiota composition in a purposeful manner. Copyright © 2009 John Wiley & Sons, Ltd. [source] Immune-stimulating and Gut Health-promoting Properties of Short-chain Fructo-oligosaccharidesNUTRITION REVIEWS, Issue 10 2002Francis R.J. Bornet M.D., Ph.D. Short-chain fructo-oligosaccharides are a group of linear fructose oligomers w ith a degree of polymerization ranging from one up to five (oligosaccharides). Recent observations in animal models demonstrate that prebiotics and probiotics may exert beneficial effects on gut health by enhancing gut-associated lymphoid tissue responses either directly or indirectly through the production of short-chain fatty acids and the enhanced growth of lactic bacteria such as bifidobacteria and lactobacilli. Demonstration of the potential health benefits of short-chain fructo-oligosaccharides on colon cancer risk is an active field of research in animal and human nutrition. [source] Effects of high- and low-fiber diets on fecal fermentation and fecal microbial populations of captive chimpanzeesAMERICAN JOURNAL OF PRIMATOLOGY, Issue 7 2009Svetlana Ki, idayová Abstract We examined fiber fermentation capacity of captive chimpanzee fecal microflora from animals (n=2) eating low-fiber diets (LFDs; 14% neutral detergent fiber (NDF) and 5% of cellulose) and high-fiber diets (HFDs; 26% NDF and 15% of cellulose), using barley grain, meadow hay, wheat straw, and amorphous cellulose as substrates for in vitro gas production of feces. We also examined the effects of LFD or HFD on populations of eubacteria and archaea in chimpanzee feces. Fecal inoculum fermentation from the LFD animals resulted in a higher in vitro dry matter digestibility (IVDMD) and gas production than from the HFD animals. However, there was an interaction between different inocula and substrates on IVDMD, gas and methane production, and hydrogen recovery (P<0.001). On the other hand, HFD inoculum increased the production of total short-chain fatty acids (SCFAs), acetate, and propionate with all tested substrates. The effect of the interaction between the inoculum and substrate on total SCFAs was not observed. Changes in fermentation activities were associated with changes in bacterial populations. DGGE of bacterial DNA revealed shift in population of both archaeal and eubacterial communities. However, a much more complex eubacterial population structure represented by many bands was observed compared with the less variable archaeal population in both diets. Some archaeal bands were related to the uncultured archaea from gastrointestinal tracts of homeothermic animals. Genomic DNA in the dominant eubacterial band in the HFD inoculum was confirmed to be closely related to DNA from Eubacterium biforme. Interestingly, the predominant band in the LFD inoculum represented DNA of probably new or yet-to-be-sequenced species belonging to mycoplasms. Collectively, our results indicated that fecal microbial populations of the captive chimpanzees are not capable of extensive fiber fermentation; however, there was a positive effect of fiber content on SCFA production. Am. J. Primatol. 71:548,557, 2009. © 2009 Wiley-Liss, Inc. [source] Nutritional significance of the selective ingestion of Albizia zygia gum exudate by wild chimpanzees in Bossou, GuineaAMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2006Kazunari Ushida Abstract The selective ingestion of plant gum exudates by chimpanzees has been frequently observed at various study sites. At Bossou, Guinea, chimpanzees also frequently ingest Albizia zygia gum exudate. A functional explanation for this behavior is lacking, so we evaluated its possible contribution of energy in the form of short-chain fatty acids (SCFA) as well as minerals. An in vitro fermentation study of A. zygia gum using the fecal bacteria of a Bossou chimpanzee showed that carboxylic acids were produced with a 6-hr lag phase up to 44 mmol/l by 18 hr of incubation. Acetate was the most abundant acid produced, followed by lactate and propionate. The energy supplied from the fermentation of a piece of gum exudate (20,30 g) was negligible in comparison with the estimated daily energy requirements of chimpanzees in the wild. However, A. zygia gum exudate (20,30 g) can supply sufficient amounts of calcium, manganese, magnesium, and potassium to fulfill the daily requirements for these minerals in chimpanzees. Am. J. Primatol. 68:143,151, 2006. © 2006 Wiley-Liss, Inc. [source] Health-beneficial effects of probiotics: Its mode of actionANIMAL SCIENCE JOURNAL, Issue 4 2009Yuji OHASHI ABSTRACT It is now widely recognized that probiotics have health-beneficial effects on humans and animals. Probiotics should survive in the intestinal tract to exert beneficial effects on the host's health. To keep a sufficient level of probiotic bacteria in the gastrointestinal tract, a shorter interval between doses may be required. Although adherence to the intestinal epithelial cell and mucus is not a universal property of probiotics, high ability to adhere to the intestinal surface might strongly interfere with infection of pathogenic bacteria and regulate the immune system. The administration of probiotic Lactobacillus stimulated indigenous Lactobacilli and the production of short-chain fatty acids. This alteration of the intestinal environment should contribute to maintain the host's health. The immunomodulatory effects of probiotics are related to important parts of their beneficial effects. Probiotics may modulate the intestinal immune response through the stimulation of certain cytokine and IgA secretion in intestinal mucosa. The health-beneficial effects, in particular the immunomodulation effect, of probiotics depend on the strain used. Differences in indigenous intestinal microflora significantly alter the magnitude of the effects of a probiotic. Specific probiotic strains suitable for each animal species and their life stage as well as each individual should be found. [source] Rapid determination of short-chain fatty acids in colonic contents and faeces of humans and rats by acidified water-extraction and direct-injection gas chromatographyBIOMEDICAL CHROMATOGRAPHY, Issue 8 2006Guohua Zhao Abstract Short-chain fatty acids (SCFAs) have attracted much attention recently because of their positive physiological effects. In this work, a rapid and reliable gas chromatographic method for determination of eight SCFAs, in colonic and faecal samples from rats and humans has been developed and validated. The methodology involves extraction of the SCFAs in water before a direct injection procedure on a FFAP capillary column. A stock standard solution containing acetic acid, propionic acid, n -butyric acid, i -butyric acid, n -valeric acid, i -valeric acid, n -caproic acid and n -heptanoic acid was prepared and used. A high line-arity (r2 > 0.9990), low quantification limit (2.38,30.14 µm) and high recovery for most acids were obtained. Acidification of faecal samples was found to be crucial for quantitative determination of the SCFAs, and adjustment of pH to 2,3 was regarded as necessary. Glass wool inserted in the glass liner of the injection port proved effective in preventing the contamination of the column by non-volatiles, and 12% formic acid reduced the ghost peak that appeared gradually after several injections. After validation, the methodology was applied on two faecal samples from rats fed diets containing different amount of dietary fibre and one faecal sample from human fed a normal diet to test the accuracy of the developed method. Copyright © 2005 John Wiley & Sons, Ltd. [source] Diversion colitis in children with colovaginoplastyBJU INTERNATIONAL, Issue 9 2001H.A. Syed Objective To highlight the occurrence of diversion colitis and its effects in colovaginoplasty. Patients and methods The records of 18 children who had undergone colovaginoplasty were reviewed retrospectively. Nine patients had androgen-insensitivity syndrome and three each had congenital adrenal hyperplasia, vaginal agenesis and Mayer,Rokitansky syndrome. Through an abdominoperineal approach a segment of sigmoid colon was isolated on its vascular pedicle and brought to the perineum in the plane between the urethra and rectum, as a blind pouch or as an interposition between the proximal vagina and the perineum. The mean (range) follow-up was 5 (1.5,8) years. Results There were no major complications during the early follow-up. Three patients developed severe vaginal discharge with bleeding 2,7 years after colovaginoplasty; examination showed erythema, oedema, ulceration and bleeding. Histology confirmed the classic features of diversion colitis in all three patients. One child responded to vaginal irrigation with a solution of short-chain fatty acids, and the other two were treated with steroid enemas and mesalazine after a poor response to short-chain fatty acids. One of these patients has required surgical reduction of an excessively long neovagina. Conclusion Symptomatic diversion colitis can occur after colovaginoplasty. The severity of the symptoms raises concerns about the use of colovaginoplasty in children and alternative techniques of vaginal replacement should be considered in the first instance. [source] Colonic short-chain fatty acids inhibit encystation of Entamoeba invadensCELLULAR MICROBIOLOGY, Issue 2 2005Jennifer Byers Summary Entamoeba parasites multiply as trophozoites in the layer of mucus that overlies the colonic epithelium. In response to stimuli that are not understood, trophozoites stop multiplying and differentiate into cysts that are released to infect another host. In the colon, Entamoeba trophozoites are exposed to the large variety of biochemicals that are carried into or are produced within this organ. The normal bacterial population of the colon releases large amounts of short-chain fatty acids (SCFAs). These compounds have effects on the growth, differentiation and repair of the colonic epithelium that correlate with de-creased activity of a Class I/II histone deacetylase (HDAC). We found that the formation of cysts, but not the growth of trophozoite-stage Entamoeba invadens parasites, was inhibited by physiologic concentrations of SCFAs. Variable levels of cyst formation did occur if SCFA concentrations were lowered. Specific inhibitors of Class I/II-type HDACs also prevented encystation, and trophozoites exposed to these compounds had increased levels of acetylation of histone H4 and other nuclear proteins. These results suggest that production of the infectious cyst stage of Entamoeba parasites is regulated in part by the levels of SCFAs made by the bacterial population of the colon. [source] | ||||||||||||||||