Improved Quantification of Prostaglandins in Biological Samples by Optimizing Simultaneously the Relationship Eicosanoid/Internal-Standard and Using Liquid Chromatography Tandem Mass Spectrometry

Although a wide variety of articles on quantification of eicosanoids by using internal standards are published every year, little has been done on how much internal standard should be added. This article demonstrates that the application of experimental design enables estimating the interaction eicosanoid/internal-standard and to select confidently an optimal amount of internal standard and a response factor (RF) for the analysis of eicosanoids in a high number of samples, where the amount of sample is limited and the unknown levels of eicosanoids are spanned in a wide range of concentrations. The results revealed that the interaction eicosanoid/internal-standard is an important factor that affects the validity of the RF and subsequently the accuracy of the analysis

Improved Quantification of Prostaglandins in Biological Samples by Optimizing Simultaneously the Relationship Eicosanoid/Internal-Standard and Using Liquid Chromatography Tandem Mass Spectrometry

Although a wide variety of articles on quantification of eicosanoids by using internal standards are published every year, little has been done on how much internal standard should be added. This article demonstrates that the application of experimental design enables estimating the interaction eicosanoid/internal-standard and to select confidently an optimal amount of internal standard and a response factor (RF) for the analysis of eicosanoids in a high number of samples, where the amount of sample is limited and the unknown levels of eicosanoids are spanned in a wide range of concentrations. The results revealed that the interaction eicosanoid/internal-standard is an important factor that affects the validity of the RF and subsequently the accuracy of the analysis.acceptedVersio

Dendritic cell populations in patients with self-reported food hypersensitivity

18th United European Gastroenterology Week, October 23-27, 2010publishedVersio

Dendritic cell populations in patients with self-reported food hypersensitivity

Self-reported hypersensitivity to food is a common condition and many of these patients have indications of intestinal immune activation. Dendritic cells (DCs) are recognized as the most potent antigen-presenting cells involved in both initiating immune responses and maintaining tolerance. The aims of this study were to evaluate the DC populations with their phenotype and T cell stimulatory capacity in patients with food hypersensitivity and to study its relationship with atopic disease. Blood samples from 10 patients with self-reported food hypersensitivity, divided into atopic and nonatopic subgroups, and 10 gender- and age-matched healthy controls were analyzed by flow cytometry using the Miltenyi Blood Dendritic cells kit. Monocyte-derived DCs (moDCs) were evaluated concerning their phenotype and T cell stimulatory capacity. DC populations and cell surface markers were not significantly different between patients and healthy controls, but moDCs from atopic patients expressed significantly more CD38 compared to moDCs from nonatopic patients. Moreover, lipopolysaccharide stimulated moDCs from atopic patients produced significantly more interleukin-10 compared to nonatopic patients. CD38 expression was correlated to total serum immunoglobulin E levels. These findings support the notion of immune activation in some patients with self-reported food hypersensitivity. They need to be confirmed in a larger cohort

Intestinal fermentation in patients with self-reported food hypersensitivity: painful, but protective?

Purpose: Enterometabolic disturbances may cause meal-related symptoms. We performed a functional evaluation of the intestinal microflora in patients with unexplained, self-reported food hypersensitivity by measuring fecal short-chain fatty acids (SCFAs). Patients and methods: Thirty-five consecutive patients with self-reported food hypersensitivity and 15 healthy volunteers of similar age, gender, and body mass index collected all feces for 72 hours. Fecal concentrations of acetic, propionic, n-butyric, i-butyric, n-valeric, i-valeric, n-caproic, and i-caproic acids were analyzed by gas-liquid chromatography. Concentrations and excretions (output) of SCFAs in patients and controls were compared and related to gastrointestinal symptoms. Results: Despite nonsignificant differences between patients and controls for both total and individual SCFA concentrations and excretions, n-butyric acid comprised a higher (P = 0.035) and acetic acid a lower (P = 0.012) proportion of total SCFA in patients compared to controls. There were no significant correlations between symptom scores and concentrations or excretions of individual or total SCFAs, but the proportion of n-butyric acid was significantly higher in patients with severe symptoms compared to patients with moderate symptoms (P = 0.016). Conclusion: The results indicate an enterometabolic disturbance in patients with self-reported food hypersensitivity. Higher proportions of n-butyric acid may be related to abdominal symptom generation, but may also protect against organic bowel disease. Further studies are needed to clarify these aspects

Intestinal permeability and faecal Granulocyte Marker Protein in Dextran Sulphate Sodium - induced colitis in rats

The aims of this preliminary study were to foster the development of an animal model of inflammatory bowel disease (IBD). We hereby studied the effects of dextran sulphate sodium (DSS) in drinking water on (a) intestinal permeability and (b) faecal levels of granulocyte marker protein (GMP) in rats. Methods were adopted to keep stress at a minimum. The animals had free access to DSS for 36 or 96 hrs. Controls received only water. Oral administration of 51Cr-labelled ethylenediaminetetraacetic acid (51CrEDTA) is used for clinical evaluation of intestinal permeability in IBD. 51CrEDTA was administered by training the animals to drink a given quantity of fluid within 5 minutes in a specific environment. On the test day, they voluntarily consumed 1 ml water containing 2 μCi 51CrEDTA. Urine samples were taken from filter paper in their home-cages for 6 hrs and radioactivity measured in a gamma counter. Faecal samples were collected after 36 and 96 hrs on DSS or water for GMP analysis. RESULTS: GMP was elevated in the DSSinduced animals after both 36 hrs (p<.05) and 96 hrs (p<.01), the elevation being greater after 96 hrs. Consumption of DSS increased the urinary excretion of 51CrEDTA after 36 hrs, but not after 96 hrs. Only DSS consumption for 96 hrs resulted in visible colonic erosions in either the proximal, mid or distal part of the colon. CONCLUSION: DSS has an acute effect upon urinary excretion of 51CrEDTA, and 96 hrs of access to DSS is sufficient to induce elevated GMP levels and colonic erosions in adult rats

Duodenal administered seal oil for patients with subjective food hypersensitivity: an explorative open pilot study

Short-term duodenal administration of n-3 polyunsaturated fatty acid (PUFA)-rich seal oil may improve gastrointestinal complaints in patients with subjective food hypersensitivity, as well as joint pain in patients with inflammatory bowel disease (IBD). The aim of the present explorative pilot study was to investigate whether 10-day open treatment with seal oil, 10 mL self-administrated via a nasoduodenal tube 3 times daily, could also benefit nongastrointestinal complaints and quality of life (QoL) in patients with subjective food hypersensitivity. Twenty-six patients with subjective food hypersensitivity, of whom 25 had irritable bowel syndrome (IBS), were included in the present study. Before and after treatment and 1 month posttreatment, patients filled in the Ulcer Esophagitis Subjective Symptoms Scale (UESS) and the Gastrointestinal Symptom Rating Scale (GSRS) for gastrointestinal symptoms and subjective health complaints (SHC) inventory for nongastrointestinal symptoms in addition to short form of the Nepean dyspepsia index (SF-NDI) for evaluation of QoL. Compared with baseline, gastrointestinal, as well as nongastrointestinal, complaints and QoL improved significantly, both at end of treatment and 1 month posttreatment. The consistent improvements following seal oil administration warrant further placebo-controlled trials for confirmation of effect

Subjective food hypersensitivity: assessment of enterochromaffin cell markers in blood and gut lavage fluid

Background: Food hypersensitivity is commonly suspected, but seldom verified. Patients with subjective food hypersensitivity suffer from both intestinal and extraintestinal health complaints. Abnormalities of the enterochromaffin cells may play a role in the pathogenesis. The aim of this study was to investigate enterochromaffin cell function in patients with subjective food hypersensitivity by measuring serum chromogranin A (CgA) and 5-hydroxytryptamine (5-HT, serotonin) in gut lavage fluid. Methods: Sixty-nine patients with subjective food hypersensitivity were examined. Twenty-three patients with inflammatory bowel disease and 35 healthy volunteers were included as comparison groups. CgA was measured in serum by enzyme-linked immunosorbent assay. Gut lavage fluid was obtained by administering 2 L of polyethylene glycol solution intraduodenally. The first clear fluid passed per rectum was collected and 5-HT was analyzed by liquid chromatography tandem mass spectrometry. Results: Serum levels of CgA were significantly lower in patients with subjective food hypersensitivity than in healthy controls (P 0.04). No differences were found in 5-HT levels in gut lavage fluid between patients with subjective food hypersensitivity and the control groups. There was no correlation between serum CgA and gut lavage 5-HT. Conclusion: Decreased blood levels of CgA suggest neuroendocrine alterations in patients with subjective food hypersensitivity. However, 5-HT levels in gut lavage fluid were normal

Short-term duodenal seal oil administration normalised n-6 to n-3 fatty acid ratio in rectal mucosa and ameliorated bodily pain in patients with inflammatory bowel disease

BACKGROUND: A high dietary intake of n-6 compared to n-3 fatty acids (FAs) may promote the production of pro-inflammatory eicosanoids and cytokines. In two recent studies, short-term (10-day) duodenal administration of n-3 polyunsaturated fatty acid rich seal oil ameliorated joint pain in patients with inflammatory bowel disease (IBD). Using unpublished data from these two studies we here investigated whether normalisation of the n-6 to n-3 FA ratio in blood and tissues by seal oil administration was associated with improved health related quality of life (HRQOL) as assessed by the generic short-form 36 (SF-36) questionnaire. RESULTS: In the first pilot study, baseline n-6 to n-3 FA ratio in rectal mucosal biopsies from 10 patients with IBD (9 of those had joint pain) was significantly increased compared with that in 10 control patients without IBD or joint pain. Following seal oil administration, the n-6 to n-3 FA ratio of the IBD-patients was significantly lowered to the level seen in untreated controls. In the subsequent, randomized controlled study (n = 19), seal oil administration reduced the n-6 to n-3 FA ratio in blood similarly and also the SF-36 assessed bodily pain, while n-6 FA rich soy oil administration had no such effect. CONCLUSION: In these two separate studies, short-term duodenal administration of seal oil normalised the n-6 to n-3 FA ratio in rectal mucosa and improved the bodily pain dimension of HRQOL of patients with IBD-related joint pain. The possibility of a causal relationship between n-6 to n-3 FA ratio in rectal mucosa and bodily pain in IBD-patients warrants further investigations

Food allergy alters jejunal circular muscle contractility and induces local inflammatory cytokine expression in a mouse model

<p>Abstract</p> <p>Background</p> <p>We hypothesized that food allergy causes a state of non-specific jejunal dysmotility. This was tested in a mouse model.</p> <p>Methods</p> <p>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-γ, IL-4, IL-6 and TGFβ-1 from jejunal and ileal tissue segments were analyzed with quantitative real-time PCR.</p> <p>Results</p> <p>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-γ and TGF-β1 remained unchanged.</p> <p>Conclusion</p> <p>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-γ 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.</p