We hypothesized that food allergy causes a state of non-specific jejunal dysmotility. This was tested in a mouse model.
Balb/c mice were epicutaneously sensitized with ovalbumin and challenged with ...10 intragastric ovalbumin administrations every second day. Smooth muscle contractility of isolated circular jejunal sections was studied in organ bath with increasing concentrations of carbamylcholine chloride (carbachol). Smooth muscle layer thickness and mast cell protease-1 (MMCP-1) positive cell density were assayed histologically. Serum MMCP-1 and immunoglobulins were quantified by ELISA, and mRNA expressions of IFN-gamma, IL-4, IL-6 and TGFbeta-1 from jejunal and ileal tissue segments were analyzed with quantitative real-time PCR.
Ovalbumin-specific serum IgE correlated with jejunal MMCP-1+ cell density. In the allergic mice, higher concentrations of carbachol were required to reach submaximal muscular stimulation, particularly in preparations derived from mice with diarrhoea. Decreased sensitivity to carbachol was associated with increased expression of IL-4 and IL-6 mRNA in jejunum. Smooth muscle layer thickness, as well as mRNA of IFN-gamma and TGF-beta1 remained unchanged.
In this mouse model of food allergy, we demonstrated a decreased response to a muscarinic agonist, and increased levels of proinflammatory IL-6 and Th2-related IL-4, but not Th1-related IFN-gamma mRNAs in jejunum. IgE levels in serum correlated with the number of jejunal MMCP-1+ cells, and predicted diarrhoea. Overall, these changes may reflect a protective mechanism of the gut in food allergy.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objectives: Irritable bowel syndrome (IBS) may be associated with disturbances in gut microbiota composition and functions. We recently performed a study of fecal microbiota transplantation (FMT) in ...diarrhea-predominant IBS (IBS-D) and found that IBS symptoms improved and the gut microbiota profile changed following FMT. We now aimed to explore the effects of FMT on the gut microenvironment in further detail by using 16S rRNA sequencing for more extended microbiota profiling and analyzing bacterial fermentation products (SCFAs: short chain fatty acids).
Materials and methods: The study included 13 patients (four females and nine males) with IBS-D according to Rome III criteria and 13 healthy donors. Freshly donated feces were administered into duodenum via gastroscopy. The patients completed symptom and quality of life (QoL) questionnaires and delivered feces before and 1, 3, 12 and 20/28 weeks after FMT. Microbiota analysis was performed by sequencing 16S rRNA gene with Illumina Miseq technology. Fecal concentrations of SCFAs were analyzed by vacuum distillation followed by gas chromatography.
Results: Several gut microbiota taxa and SCFAs were significantly different in the patients at baseline compared to their donors. These differences normalized by the third week following FMT in parallel with significant improvement in symptoms and QoL. Responders had different gut microbiota profile and SCFAs than nonresponders. Significant correlations were found between the gut microenvironment and IBS symptoms. No adverse effects were reported.
Conclusions: FMT restores alterations of the gut microenvironment in IBS-D patients during the first 3 weeks and improves their symptoms for up to 28 weeks.
ClinicalTrials.gov ID: NCT03333291.
Trial registration:
ClinicalTrials.gov identifier: NCT03333291.
"Gährungsdyspepsie" Revisited Valeur, Jørgen; Undseth, Ragnhild; Berstad, Arnold
The American journal of gastroenterology
111, Številka:
1
Journal Article
During recent years, trimethylamine N-oxide (TMAO) has emerged as a putative risk factor linking development of atherosclerosis to intake of so-called unhealthy foods (beef, egg) containing the TMAO ...precursors carnitine and choline.
Individuals with coeliac disease (CeD) often experience gastrointestinal symptoms despite adherence to a gluten-free diet (GFD). While we recently showed that a diet low in fermentable oligo-, di-, ...monosaccharides and polyols (FODMAP) successfully provided symptom relief in GFD-treated CeD patients, there have been concerns that the low FODMAP diet (LFD) could adversely affect the gut microbiota. Our main objective was therefore to investigate whether the LFD affects the faecal microbiota and related variables of gut health. In a randomised controlled trial GFD-treated CeD adults, having persistent gastrointestinal symptoms, were randomised to either consume a combined LFD and GFD (n 39) for 4 weeks or continue with GFD (controls, n 36). Compared with the control group, the LFD group displayed greater changes in the overall faecal microbiota profile (16S rRNA gene sequencing) from baseline to follow-up (within-subject β-diversity, P < 0·001), characterised by lower and higher follow-up abundances (%) of genus Anaerostipes (P
group < 0·001) and class Erysipelotrichia (P
group = 0·02), respectively. Compared with the control group, the LFD led to lower follow-up concentrations of faecal propionic and valeric acid (GC-FID) in participants with high concentrations at baseline (P
interaction ≤ 0·009). No differences were found in faecal bacterial α-diversity (P
group ≥ 0·20) or in faecal neutrophil gelatinase-associated lipocalin (ELISA), a biomarker of gut integrity and inflammation (P
group = 0·74), between the groups at follow-up. The modest effects of the LFD on the gut microbiota and related variables in the CeD patients of the present study are encouraging given the beneficial effects of the LFD strategy to treat functional GI symptoms (Registered at clinicaltrials.gov as NCT03678935).
Peptides from fish may beneficially affect several metabolic outcomes, including gut health and inflammation. The effect of fish peptides in subjects with irritable bowel syndrome (IBS) has not ...previously been investigated, hence this study aimed to evaluate the effect of a cod protein hydrolysate (CPH) supplement on symptom severity, gut integrity markers and fecal fermentation in IBS-patients. A double-blind, randomized parallel-intervention with six weeks of supplementation with 2.5 g CPH (
= 13) or placebo (
= 15) was conducted. The outcomes were evaluated at baseline and the end of the study. The primary outcomes were symptom severity evaluated by the IBS severity scoring system (IBS-SSS) and quality of life. The secondary outcomes included gut integrity markers and pro-inflammatory cytokines in serum, fecal fermentation measured by concentration of short-chain fatty acids (SCFAs) and fecal calprotectin. The groups were comparable at baseline. The total IBS-SSS-scores were reduced in both the CPH-group (298 ± 69 to 236 ± 106,
= 0.081) and the placebo-group (295 ± 107 to 202 ± 103,
= 0.005), but the end of study-scores did not differ (
= 0.395). The concentrations of serum markers and SCFAs did not change for any of the groups. The baseline measures for the whole group showed that the total SCFA concentrations were inversely correlated with the total IBS-SSS-score (
= -0.527,
= 0.004). Our study showed that a low dose of CPH taken daily by IBS-patients for six weeks did not affect symptom severity, gut integrity markers or fecal fermentation when compared to the placebo group.
AbstractObjective. Postprandial dyspepsia is common and may be associated with abnormal intragastric distribution of food. We aimed to determine the effect of body position on gastric emptying, meal ...distribution, and postprandial perceptions in healthy subjects. Material and methods. Eight adolescents (4 females and 4 males aged 14 years) were investigated using three-dimensional ultrasonography. The subjects were studied twice in a random order: once in the right lateral recumbent (RLR) position and once in the left lateral recumbent (LLR) position. Postprandial perceptions, gastric volumes, and antral areas were recorded immediately after the ingestion of 500 ml of a low-caloric meat soup over 4 min, and at 10 and 20 min following the meal. Results. Postprandial perceptions (epigastric pain, nausea, and fullness) were more pronounced in the RLR position compared to the LLR position, particularly at the end of the meal ingestion (p < 0.01). Gastric volumes were significantly smaller in the RLR position compared to the LLR position at 10 min (p < 0.01) and 20 min (p < 0.05). Antral areas were significantly wider in the RLR position compared to the LLR position at 10 min (p < 0.05) and 20 min (p < 0.01). Conclusion. Postprandial perceptions are more pronounced, gastric emptying is faster, and antral area is wider in the RLR position compared to the LLR position. The results suggest that lying on the left side after a meal may be a measure to reduce postprandial dyspeptic sensations.
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