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Background and Aims: Probiotics, prebiotics and synbiotics have been suggested as dietary strategies to improve intestinal barrier function. This study aimed to assess the effect of two weeks synbiotic supplementation on intestinal permeability under basal and stressed conditions. Secondary aims were the assessment of two weeks synbiotic supplementation on systemic immune function and gastrointestinal symptoms including defecation pattern. Design: Twenty healthy adults completed a double-blind, controlled, randomized, parallel design study. Intervention: Groups either received synbiotic (1.5 × 1010 CFU Ecologic® 825 + 10 g fructo-oligosaccharides (FOS P6) per day) or control supplements for two weeks. Outcomes: Intestinal segment specific permeability was assessed non-invasively by oral administration of multiple sugar probes and, subsequently, assessing the excretion of these probes in urine. This test was conducted at baseline and at the end of intervention, in the absence and in the presence of an indomethacin challenge. Indomethacin was applied to induce a compromised gut state. Plasma zonulin, cytokines and chemokines were measured at baseline and at the end of intervention. Gastrointestinal symptoms and stool frequency were recorded at baseline and daily during intervention. Results: Significantly more male subjects were in the synbiotic group compared to the control group (P = 0.025). Indomethacin significantly increased urinary lactulose/rhamnose ratio versus without indomethacin, both in the control group (P = 0.005) and in the synbiotic group (P = 0.017). Urinary sugar recoveries and ratios, plasma levels of zonulin, cytokines and chemokines, and gastrointestinal symptom scores were not significantly different after control or synbiotic intervention. Stool frequency within the synbiotic group was significantly increased during synbiotic intervention compared to baseline (P = 0.039) and higher compared to control intervention (P = 0.045). Conclusion: Two weeks Ecologic® 825/FOS P6 supplementation increased stool frequency, but did not affect intestinal permeability neither under basal nor under indomethacin-induced stressed conditions, immune function or gastrointestinal symptoms in healthy adults. [ABSTRACT FROM AUTHOR]

Dietary modulation of the response of gut satiety hormones, which partly regulate food intake, provides a promising treatment for overweight and obesity. Gut-derived cell lines such as STC-1 are widely used to investigate these hormonal responses to nutrients. To date, no peptide-YY (PYY) secreting cell line has been identified. The aim of this study was to investigate whether STC-1 cells are able to secrete PYY and if so, whether dietary compounds can modulate PYY secretion. The effects of fatty acid types C4:0, C12:0, C14:0, C16:0, and C18:0 on PYY release were investigated by measuring PYY in the supernatant after 30, 60, 90, and 120 min of incubation, respectively, using RIA assays. The STC-1 cells were able to secrete PYY in a time-dependent manner. It was shown that after 30 min, C4:0, C12:0, C16:0, and C18:0 caused increased PYY levels compared to the control. At time points 60 and 90 min, C4:0 and C18:0 induced elevated PYY levels compared to the control. After 120 min, C4:0, C14:0, and C18:0 caused elevated levels compared to the control. We are the first to show that the STC-1 cells are also able to secrete PYY next to cholecystokinin (CCK) and glucagon-like peptide 1 (GLP-1). Addition of fatty acids resulted in increased levels of PYY, which is consistent with the literature describing human studies. We conclude that the STC-1 cell line provides an appropriate cell line for screening the effects of ingredients on the release of the satiety-related gut hormones CCK, GLP-1, and PYY. [ABSTRACT FROM AUTHOR]

Lactoferrin (LF), an iron-binding glycoprotein present in milk and other endocrine and exocrine secretions, may exert a number of physiologic effects in the intestines. To study the effects of oral LF supplementation in vivo in the gastrointestinal tract, information about the gastric survival of LF in vivo is important. We tested 12 healthy volunteers (age 21 +/- 0.3 y) on 3 separate d according to a randomized, cross-over design. A test drink containing 4.5 g of bovine LF (20% iron-saturated LF; apoLF) in the presence of a gastric pH buffer (0.1 mol/L sodium citrate/citric acid; apoLFbuf), apoLF without the buffer (apoLF) or iron-saturated LF (holoLF) was administered into the stomach using nasogastric intubation. Gastric emptying rate, determined by a marker dilution technique, did not differ among any of these drinks. Gastric survival of LF, analyzed by gel permeation chromatography under denaturing conditions, was 64%, 62% and 79% after consumption of the apoLFbuf, apoLF and holoLF test drinks, respectively. Addition of the gastric pH buffer initially lowered intragastric pH because of its hydroxide buffering effect. However, it did not elevate intragastric pH over a prolonged period and thereby inhibit intragastric LF breakdown. We conclude that after oral administration, substantial amounts of apoLF and holoLF survive gastric transit. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The new uncoupling proteins, UCP2 and UCP3, are thought to play a role in energy efficiency in humans. Endurance training has been suggested to have effects on resting metabolic rate and energy efficiency. We therefore determined UCP2 and UCP3 mRNA levels in skeletal muscle of trained and untrained male subjects. METHODS: Using reverse transcription-polymerase chain reaction (RT-PCR), expression of UCP2, UCP3L and UCP3S mRNA were measured in muscle biopsies from the quadriceps femoris in eight trained (23.9 ± 1.6 y; 70.6 ± 3.1 kg; 14 ± 3% body fat; maximal power output (W[sub max]): 5.6 ± 0.4 W/kg; mean ± s.d.) and 10 lean, untrained (22.1 ± 2.9 y; 72.0 ± 7.9 kg; 18 ± 4% body fat; W[sub max]: 3.9? 0.4 W/kg; mean ± s.d.) subjects. In six of the trained subjects, UCP2 and UCP3 mRNA were measured before and after an exercise bout to exhaustion. To correct for differences in mitochondrial content, levels of UCP2 and UCP3 mRNA were expressed relative to cytochrome-b, a marker of mitochondrial content. RESULTS: Acute exercise had no effect on the expression of UCP3L or UCP3S, but in five out of six subjects UCP2 expression decreased after exercise, although the difference was not statistically significant (P = 0.11). Trained subjects had significantly reduced mRNA levels of UCP3L (P = 0.028) and UCP3S (P = 0.031). VO[sub 2max] expressed per kg of fat-free mass was negatively correlated with UCP3L (r = -0.61, P = 0.009) and UCP3S (r = -0.52, P = 0.028). Mechanical efficiency correlated negatively with UCP3L (r = -0.56, P = 0.019), UCP3S (r = -0.47, P = 0.048) and tended to correlate with UCP2 (r = -0.46, P = 0.06). CONCLUSION: The lower levels of UCP3 mRNA in trained subjects and the inverse relationship of UCP3 expression and mechanical efficiency suggest that exercise training produces an adaptive physiological response in skeletal muscle improving mechanical efficiency. [ABSTRACT FROM AUTHOR]

Background: The mucus layer is an important dynamic component of the epithelial barrier. It contains mucin glycoproteins and other compounds secreted by the intestinal epithelium, such as secretory IgA. However, a standardized in vivo sampling technique of mucus in humans is not yet available., Aim: To assess the validity and feasibility of mucin and protein determinations in human colonic mucus collected under physiological conditions., Subjects and Methods: Triplicate colonic mucus samples were collected in 11 healthy volunteers using cytology brushes during sigmoidoscopy. As an indication of the quantity of collected mucus, total protein and mucin concentrations were determined by measuring oligosaccharide equivalents and monosaccharides. Also secretory IgA and sialic acid concentrations were determined and proteomic analysis was performed using surface enhanced laser desorption/ionization-time of flight-mass spectrometry., Results: Mean values of secretory IgA and sialic acid corrected for the amount of mucus ranged from 0.16 to 1.81 g secretory IgA/mmol oligosaccharide equivalents and from 12.6 to 48.6g sialic acid/mmol oligosaccharide equivalents. Proteomic analysis of mucus is feasible and cluster analysis showed subject specific profiles., Conclusion: Using cytology brushes, human colonic mucus can be sampled and under physiological conditions. These samples could give information on the composition and quality of the mucus layer.