Serum markers of microbial translocation and intestinal damage in assessment of gastrointestinal tract involvement in systemic sclerosis.

Gastrointestinal (GI) tract involvement affects up to 90% of Systemic sclerosis (SSc) patients. The presence of GI symptoms is assessed by the University of California, Los Angeles, and Scleroderma Clinical Trials Consortium Gastrointestinal Scale (UCLA SCTC GIT 2.0). Microbial translocation (MT) is reported in SSc patients consequently to increased intestinal permeability due to intestinal damage (ID) and dysbiosis. Aim of this study was to assess circulating levels of LBP and EndoCab IgM (markers of MT), IL-6 (marker of inflammation), I-FABP and Zonulin (markers of ID) in a cohort of SSc patients and healthy controls (HC). Moreover, we aimed to correlate these parameters with severity of GI symptoms. UCLA SCTC GIT 2.0 questionnaire was administered to 60 consecutive SSc patients. Markers of MT, inflammation and ID were evaluated in SSc patients and HC. SSc patients had higher median value of markers of MT, inflammation and ID than HC. The logistic regression analysis showed LBP as the only variable associated with an UCLA total score "moderate-to-very severe" [OR 1.001 (CI 95%: 1.001-1.002), p < 0.001]. The logistic regression analysis showed LBP [OR 1.002 (CI 95%: 1.001-1.003), p < 0.01] and disease duration [OR 1.242 (CI 95%: 1.023-1.506), p < 0.05] as variables associated with UCLA distension/bloating "moderate-to-very severe". The logistic regression analysis showed LBP as the only variable associated with UCLA diarrhea "moderate-to-very severe" [OR 1.002 (CI 95%: 1.001-1.003), p < 0.01]. SSc patients with dysregulation gut mucosal integrity expressed by high levels of MT and ID biomarkers had more severe GI symptoms.

Functional Gastrointestinal Symptoms in Children with Autism and ADHD: Profiles of Hair and Salivary Cortisol, Serum Leptin Concentrations and Externalizing/Internalizing Problems.

BACKGROUND: Functional Gastrointestinal Disorders (FGIDs) present a higher prevalence in individuals with Neurodevelopmental Disorders (NDDs). The Stress System and the Gut-Brain axis (GBA) may mediate these relations. We aimed to assess the prevalence and profile of FGIDs in a clinical sample of children with Autism Spectrum Disorder (ASD) and Attention Deficit/Hyperactivity Disorder (ADHD) compared to typically developing children (TD) as well as to investigate possible relations between stress-related biomarkers and internalizing/externalizing problems in children with NDDS. METHODS: In total, 120 children, aged between 4 and 12 years old, formed three groups (N = 40, each): ADHD, ASD and TD. Salivary cortisol, hair cortisol and serum leptin were measured. RESULTS: The ASD group had more FGID problems than the TD group (p = 0.001). The ADHD and ASD groups had higher total internalizing/externalizing problems than the TD group (p < 0.0001, p < 0.0001, p = 0.005, respectively). Children with FGIDs showed more total, internalizing and externalizing problems compared to children without FGIDs (p < 0.0001, p < 0.0001, p = 0.041, respectively). The ADHD group showed lower AUCg values (p < 0.0001), while the hair cortisol was higher for the TD group (p < 0.0001). CONCLUSION: In conclusion, children with NDDs had more FGID symptoms and present higher internalizing and externalizing problems. Children with ADHD and FGIDs had more internalizing problems compared to those without FGIDs. No differences in stress-related biomarkers were shown to differentiate children with NDDs with and without FGIDs. Future prospective studies including a greater number of children may elucidate the biological pathways linking these comorbidities.

Evaluation of gastrointestinal tract lesions and serum malondialdehyde levels after repeated oral administration of phenylbutazone in horses.

Phenylbutazone (PBZ) is a widely used nonsteroidal anti-inflammatory drug for horses. However, because of its gastrointestinal side effects, its administration requires careful attention in veterinary practice. Malondialdehyde (MDA) is a serum biomarker associated with increased damage to the equine gastrointestinal system. This study investigated the hematological effects and alterations in the gastrointestinal tract and assessed serum MDA concentrations following repeated oral PBZ administration at clinical doses. Fourteen horses were randomly divided into control and treatment groups. All horses in the treatment group were administered 4.4 milligrams per kilogram of body weight of PBZ syrup orally twice a day for 7 days, whereas the control group received syrup as a placebo. The development of gastrointestinal side effects was investigated using gastroscopy, abdominal ultrasound, and fecal pH; serum MDA concentrations were assessed using a commercially available enzyme-linked immunosorbent assay kit. Data were compared between PBZ-treated and control horses before and after the treatment period. The treatment group exhibited decreased albumin and total protein concentrations. Moreover, this group exhibited a higher thickness of the right dorsal colon wall (p = 0.03) and had higher scores for squamous gastric ulcers (p = 0.01). Fecal pH was lower in the treatment group than in the control group after PBZ administration (p < 0.01). Although MDA concentrations were higher in the treatment group after PBZ administration, they did not differ significantly from those of the control group. This study highlighted the changes in hematological and gastrointestinal lesions resulting from PBZ administration in horses at clinical doses, even without clinical signs. However, MDA may not be an optimal biomarker for the early detection of gastrointestinal damage due to PBZ treatment in horses.

Intestinal Fatty Acid-Binding Protein as a Potential Biomarker for Gastrointestinal Complications after Complex Endovascular Aortic Surgery.

BACKGROUND: This study aimed to investigate the association between intestinal fatty acid-binding protein (I-FABP), acute gastrointestinal injury (AGI) grade, and gastrointestinal (GI) complications after fenestrated or branched endovascular aortic aneurysm repair. METHODS: A total of 17 patients undergoing endovascular aortic repair for thoracoabdominal, juxtarenal, suprarenal, or pararenal aneurysm between May 2017 and September 2018 were enrolled. Blood samples were collected preoperatively and during postoperative intensive care. The blood samples were analyzed for I-FABP with enzyme-linked immunosorbent assay. Gastrointestinal function was assessed according to the AGI grade every day during postoperative intensive care. RESULTS: Higher concentrations of I-FABP at 24 hr and 48 hr correlated to higher AGI grade on postoperative days 1, 2, and 3 (P = 0.032 and P = 0.048, P = 0.040 and P = 0.018, and P = 0.012 and P = 0.016, respectively). Patients who developed a GI complication within 90 days postoperatively had a higher overall AGI grade than those who did not develop a GI complication (P < 0.001), as well as higher concentrations of I-FABP at 48 hrs (P = 0.019). Patients developing GI dysfunction (AGI grade ≥2) had a higher frequency of complications (P = 0.009) and longer length of stay in the intensive care unit (P = 0.008). CONCLUSIONS: In patients undergoing endovascular aortic repair for complex aneurysm increased postoperative plasma I-FABP concentrations and postoperative GI dysfunction, evaluated using the AGI grade, were associated with GI complications, indicating that these measures may be useful in the postoperative management of these patients.

Serum Calprotectin in the Evaluation of Gastrointestinal Diseases: An Ace up Your Sleeve?

Background: Calprotectin (CP) is a calcium- and zinc-binding protein that plays a key role in innate immunity and in the recruitment of inflammatory cells. CP can be detected both in serum and in fecal samples. Serum CP (sCP) is more specific for autoimmune diseases, while fecal CP (fCP) has been well investigated for gastrointestinal diseases. Few studies have shown the clinical effectiveness of sCP as an acute-phase biomarker for gastrointestinal diseases. Aim: The aim of this narrative review is to discuss the role of sCP as a useful alternative biomarker of the acute-phase activity of gastrointestinal diseases and as a possible tool for screening and monitoring these diseases. Material and Methods: We searched original articles, abstracts, reviews, case reports, and clinical trials on PubMed®, Up-to-Date®, and Medscape® in the last ten years. Conclusion: We found that sCP could represent a useful biomarker in the evaluation of the inflammatory stage in patients with immune-mediated gastrointestinal diseases, but more studies are needed to promote its routine use in clinical practice as a diagnostic and prognostic biomarker as a replacement for fCP.

The effect of feeding on serum concentrations of cobalamin, folate, trypsin-like immunoreactivity, and pancreatic lipase immunoreactivity in dogs with signs of chronic gastrointestinal disease.

BACKGROUND: It is unknown if serum concentrations of cobalamin, folate, canine pancreatic lipase immunoreactivity (cPLI), and canine trypsin-like immunoreactivity (cTLI) obtained postprandially are equivalent to measurements obtained after withholding food in dogs with suspected gastrointestinal disease. HYPOTHESIS/OBJECTIVES: Measurements of serum concentrations of cobalamin, folate, cPLI, and cTLI postprandially will be equivalent to measurements after 12 hours of withholding food in dogs with signs of chronic gastrointestinal disease. Changes observed will not alter clinical interpretation. ANIMALS: 51 client-owned dogs with signs of gastrointestinal disease. METHODS: Prospective single arm clinical trial. Serum concentrations of cobalamin, folate, cPLI and cTLI 2, 4, and 8 hours postprandially were compared by equivalence testing to values after withholding food for 12 hours (baseline). RESULTS: Mean serum cobalamin concentrations 2 hours (498.1 ± 213.1 ng/L; P = 0.024) and 4 hours (501.9 ± 207.4 ng/L; P = 0.008) postprandial were equivalent to baseline (517.3 ± 211.5 ng/L). Mean serum cTLI 2 hours (31.3 ± 14 µg/L; P < 0.001) and 4 hours (29.6 ± 13.1 µg/L; P = 0.027) postprandial were equivalent to baseline (31.1 ± 15 µg/L). Mean serum folate concentration 2 hours postprandial (15 ± 7.7 µg/L) was equivalent to baseline (13.7 ± 8.3 µg/L; P < 0.001). Equivalence could not be assessed for cPLI due to results below the lower limit of quantification. Feeding altered the clinical interpretation in 27% (cobalamin), 35% (folate), 20% (cTLI), and 12% (cPLI) of dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The clinical interpretation for a substantial number of samples changed after feeding, therefore withholding food before sample collection is prudent.

Development of a plasma maltose assay method as a screening test for upper gastrointestinal disorders.

BACKGROUND AND OBJECTIVE: The disaccharide loading test is a method to assess gastric mucosal damage. Since Trelan-G75, which is used for the sugar tolerance test, contains disaccharide maltose, if maltose is detected at a high sensitivity in the sample blood used in the sugar tolerance test, screening for upper gastrointestinal mucosal damage can be made simultaneously with the sugar tolerance test for the diagnosis of diabetes. METHODS: Glucose-6-phosphate is generated by treating maltose with maltose phosphorylase, ß-phosphoglucomutase, and glucose-1,6-bisphosphate. Then, change in the absorbance at 405 nm is measured by the enzymatic cycling method using Thio-NADP, ß-NADPH, and Glucose-6-phosphate dehydrogenase. After evaluating the optimal condition for this method, it is mounted on an automatic biochemical analyzer, and samples after the sugar tolerance test were assayed. RESULTS: Regarding the performance of this method, the repeatability was 10-50 µmol/L with a CV of ≤1.1%. Concerning the assay range, a curve passing the origin with a range of linearity up to 120 µmol/L was obtained. No effect of dyes or sugars in the blood was noted. As a result of application to patients with gastric mucosal disorders (those who had a health checkup), significant differences were observed depending on the stage of atrophic gastritis. DISCUSSION: This method has a high sensitivity and a high precision and can be used for high-speed analysis on an automatic analyzer. It has the potential to be used as a screening test for gastric mucosal damage.

Activating Transcription Factor 3 Protects against Restraint Stress-Induced Gastrointestinal Injury in Mice.

Psychological stress increases the risk of gastrointestinal (GI) tract diseases, which involve bidirectional communication of the GI and nerves systems. Acute stress leads to GI ulcers; however, the mechanism of the native cellular protection pathway, which safeguards tissue integrality and maintains GI homeostasis, remains to be investigated. In a mouse model of this study, restraint stress induced GI leakage, abnormal tight junction protein expression, and cell death of gut epithelial cells. The expression of activating transcription factor 3 (ATF3), a stress-responsive transcription factor, is upregulated in the GI tissues of stressed animals. ATF3-deficient mice displayed an exacerbated phenotype of GI injuries. These results suggested that, in response to stress, ATF3 is part of the native cellular protective pathway in the GI system, which could be a molecular target for managing psychological stress-induced GI tract diseases.

A pilot study evaluating the Calibrated Automated Thrombogram assay and application of plasma-thromboelastography for detection of hemostatic aberrations in horses with gastrointestinal disease.

BACKGROUND: Critically ill horses, such as horses with gastrointestinal (GI) disease, often suffer from hemostatic aberrations. Global hemostatic tests examining the initiation of coagulation, clot strength and fibrinolysis, such as the Calibrated Automated Thrombogram (CAT) and plasma-thromboelastography (TEG) have not been evaluated in horses. This study aimed to evaluate CAT and apply plasma-TEG in horses. Test performance of CAT was evaluated on equine platelet poor plasma with intra- and inter-assay variability (CV) and a heparin dilution curve. To examine clinical performance of both tests, group comparisons were assessed comparing healthy horses, horses with mild and severe GI disease with both CAT and plasma-TEG. RESULTS: For CAT, intra- and inter-assay CVs were established for lag-time (1.7, 4.7%), endogenous thrombin potential (1.6, 4.6%), peak (2.6, 3.9%) and time to peak (ttPeak) (1.9, 3.4%). Increasing heparin concentrations led to the expected decrease in thrombin generation. In the group comparison analysis, CAT showed significant higher peak (p = 0.04) and ttPeak (p = 0.008) in the severe GI disease group compared to horses with mild GI disease and healthy horses, respectively. Plasma-TEG showed an increased angle (p = 0.032), maximum amplitude (p = 0.017) and shear elastic force (G) (p = 0.017) in the severe GI disease group compared to healthy horses. CONCLUSIONS: CAT performed well in horses. Both CAT and plasma-TEG identified hemostatic aberrations in horses with severe GI disease compared to healthy horses. Further studies including more horses, are needed to fully appreciate the use of CAT and plasma-TEG in this species.

Correlations of Serological Markers with Development of Systemic Involvement in Adult Immunoglobulin A Vasculitis: A Retrospective Study of 259 Patients in Central China.

OBJECTIVE: Although relatively rare, adult immunoglobulin A vasculitis (IgAV) can lead to severe complications and longer hospitalization, and result in poor prognosis, when compared to childhood IgAV. Hence, early identification and prevention for patients prone to develop systemic involvement are essential. The purpose of this study was to explore the correlations of common serological markers with the development of systemic involvement in adult IgAV. METHODS: A retrospective analysis was performed for adult IgAV patients, who were hospitalized in Wuhan Union Hospital between January 2016 and December 2019. A total of 259 patients were enrolled, and the pre-treatment serological markers were comprehensively assessed. RESULTS: In the present study, 49.0% and 33.2% of patients developed renal and gastrointestinal (GI) involvement, respectively. Furthermore, the elevated levels of white blood cells count, D-Dimer (D-D), C-reactive protein (CRP) and neutrophil granulocyte ratio (NE%) >60% were significantly associated with GI involvement in the univariate analysis, while the decrease in high density lipoprotein level, and the elevated D-D and CRP levels were significantly associated with renal involvement (P<0.05). Moreover, a prediction model that combined multiple markers was established by performing a logistic regression analysis, and this presented a more favorable value of prediction than the individual serological markers. CONCLUSION: The present study suggests that common serological markers have close correlations with systemic involvement in adult IgAV, and that the establishment of a prediction model for systemic involvement may be helpful in facilitating personalized therapeutic strategies and clinical management for IgAV patients.

Trefoil factor-2, an early predictor for acute gastrointestinal injury in patients with acute pancreatitis.

ABSTRACT: Acute gastrointestinal injury (AGI) is commonly present in patients with acute pancreatitis (AP). It is often difficult to predict gastrointestinal function in the early stage due to lack of reliable markers. We aimed to assess whether early plasma trefoil factor 2 (TFF-2) is a potential predictor for AGI.Fifty one patients were included for the onset of AP (from developing abdominal pain) within 72 hours in this prospective observational single-center study from January 2013 to July 2015. Among them 23 patients were classified as mild, 17 as moderately severe, and 11 as severe according to 2012 Atlanta classification. Plasma samples were collected only once at admission to the ICU. Twenty samples of healthy adults were also collected as control. The TFF-2 levels were determined by using a human TFF-2 enzyme-linked immunoassay. AGI grades from 1st to 7th day after admission were observed.The plasma TFF-2 levels among AP patients in early stage were significantly higher than healthy controls (766.41 ng/mL vs 94.37 ng/mL, P < .0001). The correlations between TFF-2 levels and AGI grades from 1st to 4th day after admission were positive (r = 0.47, 0.43, 0.42, 0.40 respectively, P < .05). As a predictor of acute gastrointestinal failure, plasma TFF-2 was superior to others: Acute Physiology and Chronic Health Evaluation II, sequential organ failure assessment, procalcitonin, C-reactive protein, serum calcium. In addition, TFF-2 increased along with the severity of AP (r = 0.554, P < .0001) and associated with Acute Physiology and Chronic Health Evaluation II, sequential organ failure assessment, C-reactive protein, serum calcium.The plasma TFF-2 levels were increased in patients in early stage of AP and correlated with AGI grades and disease severity in our study. TFF-2 might be a potential predictor for acute gastrointestinal failure in patients with AP.

Association of gastrointestinal parasite burden, serum cytokines and hormones concentrations, and pregnancy in Angus-cross beef cows.

The objective was to elucidate the relationships among gastrointestinal (GI) parasite load, serum cytokines (Th 1 - Interleukin (IL) 2, Interferon (IFN) γ and Tumor necrosis factor (TNF) α; Th 2- IL4, IL6, and IL10) levels, hormones (progesterone, cortisol, 8-epi-prostaglandin F2 alpha (isoprostane), prolactin, substance-p, and prostaglandin F metabolites) concentrations, and pregnancy in beef cattle. Angus-cross beef cows (n = 700; age, 3-8 y) were blocked by age and body condition score (BCS, 1-9), and were randomly assigned to treatment (n = 350, TRT, 50 mg of eprinomectin/50 kg BW, im) or control (n = 350, CON, no treatment) on Day -30. Cows were synchronized using Controlled Internal Drug Release insert (CIDR) + CO-Synch protocol and artificially inseminated at a fixed time on Day 0 (66 h after CIDR removal). Fecal samples were collected to determine fecal egg count per gram (FEG, McMaster method) on Days -30, -23, -16, -7, 7, 0, 16 and 23, and blood samples were collected on Days -7, 0, 7, 16 and 23. Serum cytokines were determined on Days -7, 0, 7, 16 and 23, and circulating hormones were measured on Day 16. BCS were recorded on Day 16 following artificial insemination (AI), and pregnancy status was diagnosed on Day 30 and 60. Pregnancy/AI varied among treatment groups on Day 30 [TRT, 62.0% (217/350); CON, 54.9% (192/350) (P = 0.05)] and Day 60 [TRT, 60.9% (213/350); CON, 51.7% (181/350) (P < 0.05)]. Pregnancy loss between 30 and 60 days for TRT and CON groups were 1.8% (4/217) and 5.7% (11/192), respectively (P < 0.05). The BCS on Day 16 did not differ among treatment groups (P> 0.1). Four groups of 40 cows were selected based on their pregnancy status and treatment: pregnant, TRT; non-pregnant, TRT; pregnant, CON; and non-pregnant, CON to compare the mean FEG, cytokines, and hormones levels. The FEG and cytokine concentrations were significantly (P < 0.05) influenced by treatment, pregnancy status, day, treatment by pregnancy status, and treatment by day. Day 16 hormone concentrations were considerably influenced by treatment, pregnancy status, and treatment by pregnancy. Although FEG on Day -30 did not differ among the groups (P> 0.1), it was lower in treated, pregnant cows compared with cows in other three groups from Day -23 onwards (P < 0.05). Overall and pairwise comparisons showed that serum concentrations of Type 1 cytokines, IL2, IFNγ, and TNFα were lower (P < 0.05) from gestational Day 7 onwards in treated, pregnant cows compared with cows in other three groups. In contrast, serum concentrations of Type 2 cytokines, IL4, IL6 and IL10 were greater (P < 0.05) from gestational Day 7 onwards in treated, pregnant cows compared with cows in other groups. Serum concentrations of progesterone was greater and other hormones were lower for pregnant cows in TRT group compared to cows in other groups on gestational Day 16. In conclusion, GI parasite load was reduced; Th 1 cytokines levels were decreased; Th 2 cytokines concentrations were increased; progesterone level was increased; and cortisol, substance-P, prolactin, isoprostane, and PGFM were decreased in pregnant, TRT cows. These changes also resulted in an increase in P/AI. It is plausible that direct and bidirectional host-parasite interactions mediated by cytokines and hormones may have promoted maternal tolerance of an immunologically diverse conceptus and the establishment of pregnancy.

Mechanisms of Gegen Qinlian Pill to ameliorate irinotecan-induced diarrhea investigated by the combination of serum pharmacochemistry and network pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine suggests the use of natural extracts and compounds is a promising strategy to prevent irinotecan (CPT-11)-induced gut toxicity and resulting diarrhea. Previous work from our lab indicated the protective effect of Gegen Qinlian decoction; given this, we further speculated that Gegen Qinlian Pill (GQP) would exhibit similar therapeutic effects. The effective material basis as well as potential mechanisms underlying the effect of GQP for the treatment of CPT-11-induced diarrhea have not been fully elucidated. AIM OF THE STUDY: The application of natural extracts or compounds derived from Chinese medicine is deemed to a promising strategy to prevent irinotecan (CPT-11)-induced gut toxicity. The aim of this study was to investigated the beneficial effects of GQP on CPT-11-induced gut toxicity and further explored its anti-diarrheal mechanism. METHODS: First, the beneficial effect of GQP in alleviating diarrhea in mice following CPT-11 administration was investigated. We also obtained the effective ingredients in GQP from murine serum samples using HPLC-Q-TOF-MS analysis. Based on these active components, we next established an interaction network linking "compound-target-pathway". Finally, a predicted mechanism of action was obtained using in vivo GQP validation based on Gene Ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. RESULTS: A total of 19, GQP-derived chemical compounds were identified in murine serum samples. An interaction network linking "compound-target-pathway" was then established to illuminate the interaction between the components present in serum and their targets that mitigated diarrhea. These results indicated GQP exerted a curative effect on diarrhea and diarrhea-related diseases through different targets, which cumulatively regulated inflammation, oxidative stress, and proliferation processes. CONCLUSION: Taken together, this study provides a feasible strategy to elucidate the effective constituents in traditional Chinese medicine formulations. More specifically, this work detailed the basic pharmacological effects and underlying mechanism behind GQP's effects in the treatment of CPT-11-induced gut toxicity.

An assessment of potential biomarkers of environment enteropathy and its association with age and microbial infections among children in Bangladesh.

Interventional studies targeting environment enteropathy (EE) are impeded by the lack of appropriate, validated, non-invasive biomarkers of EE. Thus, we aimed to validate the association of potential biomarkers for EE with enteric infections and nutritional status in a longitudinal birth cohort study. We measured endotoxin core antibody (EndoCab) and soluble CD14 (sCD14) in serum, and myeloperoxidase (MPO) in feces using commercially available enzyme-linked immunosorbent assay (ELISA) kits. We found that levels of serum EndoCab and sCD14 increase with the cumulative incidence of enteric infections. We observed a significant correlation between the fecal MPO level in the children at 24 months of age with the total number of bacterial and viral infections, the total number of parasitic infections, and the total number of diarrheal episodes and diarrheal duration. We observed that the levels of serum EndoCab, sCD14, and fecal MPO at 3 months of age were significantly associated with whether children were malnourished at 18 months of age or not. Biomarkers such as fecal MPO, serum EndoCab and sCD14 in children at an early age may be useful as a measure of cumulative burden of preceding enteric infections, which are predictive of subsequent malnutrition status and may be useful non-invasive biomarkers for EE.

Fructose intolerance is not associated with malabsorption in patients with functional gastrointestinal disorders.

BACKGROUND: Symptoms following fructose ingestion, or fructose intolerance, are common in patients with functional gastrointestinal disorders (FGID) and are generally attributed to intestinal malabsorption. The relationships between absorption, symptoms, and intestinal gas production following fructose ingestion were studied in patients with FGID. METHODS: Thirty FGID patients ingested a single dose of fructose 35 g or water in a randomized, double-blind, crossover study. Blood and breath gas samples were collected, and gastrointestinal symptoms rated. Plasma fructose metabolites and short-chain fatty acids were quantified by targeted liquid chromatography-tandem mass spectrometry. Patients were classified as fructose intolerant or tolerant based on symptoms following fructose ingestion. KEY RESULTS: The median (IQR) areas under the curve of fructose plasma concentrations within the first 2 h (AUC0-2 h ) after fructose ingestion were similar for patients with and without fructose intolerance (578 (70) µM·h vs. 564 (240) µM·h, respectively, p = 0.39), as well as for the main fructose metabolites. There were no statistically significant correlations between the AUC0-2 h of fructose or its metabolites concentrations and the AUCs of symptoms, breath hydrogen, and breath methane. However, the AUCs of symptoms correlated significantly and positively with the AUC0-2 h of hydrogen and methane breath concentrations (r = 0.73, r = 0.62, respectively), and the AUCs of hydrogen and methane concentrations were greater in the fructose-intolerant than in the fructose-tolerant patients after fructose ingestion (p ≤ 0.02). CONCLUSIONS & INFERENCES: Fructose intolerance in FGID is not related to post-ingestion plasma concentrations of fructose and its metabolites. Factors other than malabsorption, such as altered gut microbiota or sensory function, may be important mechanisms.

Small intestinal immunopathology and GI-associated antibody formation in hereditary alpha-tryptasemia.

BACKGROUND: Hereditary alpha-tryptasemia (HαT) is characterized by elevated basal serum tryptase due to increased copies of the TPSAB1 gene. Individuals with HαT frequently present with multisystem complaints, including anaphylaxis and seemingly functional gastrointestinal (GI) symptoms. OBJECTIVE: We sought to determine the prevalence of HαT in an irritable bowel syndrome cohort and associated immunologic characteristics that may distinguish patients with HαT from patients without HαT. METHODS: Tryptase genotyping by droplet digital PCR, flow cytometry, cytometry by time-of-flight, immunohistochemistry, and other molecular biology techniques was used. RESULTS: HαT prevalence in a large irritable bowel syndrome cohort was 5% (N = 8/158). Immunophenotyping of HαT PBMCs (N ≥ 27) revealed increased total and class-switched memory B cells. In the small bowel, expansion of tissue mast cells with expression of CD203c, HLA-DR, and FcεRI, higher intestinal epithelial cell pyroptosis, and increased class-switched memory B cells were observed. IgG profiles in sera from individuals with HαT (N = 21) significantly differed from those in individuals with quiescent Crohn disease (N = 20) and non-HαT controls (N = 19), with increased antibodies directed against GI-associated proteins identified in individuals with HαT. CONCLUSIONS: Increased mast cell number and intestinal epithelial cell pyroptosis in the small intestine, and class-switched memory B cells in both the gut and peripheral blood associated with IgG reactive to GI-related proteins, distinguish HαT from functional GI disease. These innate and adaptive immunologic findings identified in association with HαT are suggestive of subclinical intestinal inflammation in symptomatic individuals.

Distinct Small Intestine Mast Cell Histologic Changes in Patients With Hereditary Alpha-tryptasemia and Mast Cell Activation Syndrome.

Mast cells (MCs) are important in intestinal homeostasis and pathogen defense but are also implicated in many of the clinical manifestations in disorders such as irritable bowel syndrome. The utility of specific staining for MCs to quantify and phenotype them in intestinal biopsies in patients with gastrointestinal (GI) symptoms is controversial and is not a widely adopted practice. Whether or not intestinal MCs are increased or have a unique phenotype in individuals with hereditary alpha-tryptasemia (HαT), who have extra copies of the MC tryptase gene TPSAB1 and typically elevated baseline serum tryptase levels >8 ng/mL is not known. We examined the duodenal biopsies of 17 patients with HαT and compared them to 15 patients with mast cell activation syndrome who had baseline serum tryptases <8 ng/mL (MCAS-NT) and 12 GI-controls. We determined that the HαT subjects had increased MCs in the duodenum compared with MCAS-NT and GI-controls (median=30.0; interquartile range [IQR]: 20.0 to 40.0 vs. median=15.0; IQR: 5.00 to 20.0; P=0.013 and median=15.0; IQR: 13.8 to 20.0; P=0.004, respectively). These MCs were significantly found in clusters (<15 MCs) and were located throughout the mucosa and submucosa including the superficial villi compared with MCAS-NT and GI-control patients. Spindle-shaped MCs were observed in all groups including controls. These data demonstrate that HαT is associated with increased small intestinal MCs that may contribute to the prevalent GI manifestations observed among individuals with this genetic trait.

Angiopoietin-2 Is an Early Predictor for Acute Gastrointestinal Injury and Intestinal Barrier Dysfunction in Patients with Acute Pancreatitis.

BACKGROUNDS: Angiopoietin-2 (Ang-2) is a new predictor for acute pancreatitis (AP). AIMS: To assess the predictive value of Ang-2 in determining the progress of AP and the subsequent acute gastrointestinal injury (AGI). METHODS: This was a prospective study that enrolled 170 patients with AP and 100 healthy controls. Blood samples were collected within 24 h of the onset of AP. RESULTS: The majority (108) of the patients were categorized as having MAP with the rest (62) classified as suffering from SAP. Considering AGI grading, there were 118 grade 1 and 12 grade 4 patients; in grades 2 and 3, there were 20 patients each. AP was accompanied by MODS and pancreatic necrosis in 46 and 24 cases, respectively. Eighty patients were admitted to the ICU, while mortality was reported among 7.1% patients. The plasma Ang-2 levels were higher among patients with AP than in controls. A similar trend prevailed, in patients with SAP compared to those with MAP. Ang-2 was significantly increased from AGI grade 1 through to grade 4, showing a desirable positive predictive accuracy. Moreover, Ang-2 also showed strong correlations with intestinal permeability as evaluated by d-lactate (DLA), diamine oxidase (DAO), and intestinal fatty acid binding proteins (I-FABPs). Tools (Ranson and APACHE II scores, CRP), which are used more conventionally, could not effectively distinguish the various grades of AGI. Furthermore, Ang-2 predicted poor prognosis and adverse outcomes, including mortality, among patients with AP. CONCLUSIONS: This study showed Ang-2 to be an accurate early predictor for SAP, AGI, and intestinal barrier dysfunction, outperforming conventional biomarkers. Ang-2 levels also predicted the adverse outcomes and mortality due to AP.

Diurnal versus Nocturnal Exercise-Effect on the Gastrointestinal Tract.

PURPOSE: The study aimed to determine the effect of diurnal versus nocturnal exercise on gastrointestinal integrity and functional responses, plasma lipopolysaccharide binding protein (LBP) and soluble CD14 (sCD14) concentrations (as indirect indicators of endotoxin responses), systemic inflammatory cytokine profile, gastrointestinal symptoms, and feeding tolerance. METHODS: Endurance runners (n = 16) completed 3 h of 60% V˙O2max (22.7°C, 45% relative humidity) running, on one occasion performed at 0900 h (400 lx; DAY) and on another occasion at 2100 h (2 lx; NIGHT). Blood samples were collected pre- and postexercise and during recovery to determine plasma concentrations of cortisol, catecholamines, claudin-3, I-FABP, LBP, and sCD14 and inflammatory cytokine profiles by ELISA. Orocecal transit time (OCTT) was determined by lactulose challenge test given at 150 min, with concomitant breath hydrogen (H2) and gastrointestinal symptom determination. RESULTS: Cortisol increased substantially pre- to postexercise on NIGHT (+182%) versus DAY (+4%) (trial-time, P = 0.046), with no epinephrine (+41%) and norepinephrine (+102%) trial differences. I-FABP, but not claudin-3, increased pre- to postexercise on both trials (mean = 2269 pg·mL-1, 95% confidence interval = 1351-3187, +143%) (main effect of time [MEOT], P < 0.001). sCD14 increased pre- to postexercise (trial-time, P = 0.045, +5.6%) and was greater on DAY, but LBP decreased (MEOT, P = 0.019, -11.2%) on both trials. No trial difference was observed for systemic cytokine profile (MEOT, P = 0.004). Breath H2 responses (P = 0.019) showed that OCTT was significantly delayed on NIGHT (>84 min, with n = 3 showing no breath H2 turning point by 180 min postexercise) compared with DAY (mean = 54 min, 95% confidence interval = 29-79). NIGHT resulted in greater total gastrointestinal symptoms (P = 0.009) compared with DAY. No difference in feeding tolerance markers was observed between trials. CONCLUSION: Nocturnal exercise instigates greater gastrointestinal functional perturbations and symptoms compared with diurnal exercise. However, there are no circadian differences to gastrointestinal integrity and systemic perturbations in response to the same exertional stress and controlled procedures.

Increasing Expiratory Hydrogen in Lactose Intolerance Is Associated with Additional Food Intolerance/Malabsorption.

Single and/or combined food intolerance/malabsorption may cause nonspecific, functional gastrointestinal (GI) complaints. In lactose-intolerant patients we evaluated the influence of additional food intolerance/malabsorption with hydrogen (H2) breath tests. In a retrospective analysis of charts from 279 lactose-intolerant patients, we found 128 patients with only lactose intolerance (LIT). Then, we identified 106 LIT patients with additional histamine intolerance (HIT). Additionally, 45 LIT and HIT patients also had fructose malabsorption (FM). A hydrogen (H2) breath test was performed to evaluate LIT and FM. A serum diamine oxidase value of <10 U/mL and a response to a histamine-reduced diet was used to identify HIT. Using pairwise comparison with the Kruskal-Wallis test to associate the area under the curve (AUC) of LIT patients and, LIT with HIT, to LIT with HIT and FM it was found, that the exhaled hydrogen values were significantly higher in patients with two-fold and triple combined food intolerance/malabsorption (p < 0.004 and p < 0.001, respectively). Within the pool of 170 LIT patients with >20 ppm increase of expiratory H2 from baseline, there were 74 LIT-only patients, 60 LIT with HIT patients, and 36 LIT patients with additional HIT and FM. With the Kruskal-Wallis test AUCs demonstrated a significant difference between all three groups (p = 0.024). In patients with LIT, the presence of additional food intolerance/malabsorption, significantly increases expiratory H2 values. We demonstrate evidence, which may suggest HIT to embody an own GI disorder as food intolerance/malabsorption.