Leda Roncoroni

Evidence for the presence of non-celiac gluten sensitivity in patients with functional gastrointestinal symptoms: Results from a multicenter randomized double-blind placebo-controlled gluten challenge

Non-celiac gluten sensitivity (NCGS) is characterized by the onset of symptoms after eating gluten-containing food. We aimed to single out NCGS subjects among subjects with functional gastrointestinal symptoms. Patients were enrolled in a multicenter double-blind placebo-controlled trial with crossover. Symptoms and quality of life were evaluated by means of 10-cm VAS and SF36. Iron parameters, transaminases and C reactive protein (CRP) were evaluated. After a three-week-long gluten-free diet (GFD), responsive patients were randomly assigned to gluten intake (5.6 g/day) or placebo for seven days, followed by crossover. The primary endpoint was the worsening of symptoms (VAS increase ≥3 cm) during gluten ingestion compared to placebo. One hundred and forty patients were enrolled and 134 (17 males, mean age 39.1 ± 11.7 years, BMI 22.4 ± 3.8) completed the first period. A total of 101 subjects (10 males, mean age 39.3 ± 11.0 years, BMI 22.3 ± 4.0) reported a symptomatic improvement (VAS score 2.3 ± 1.2 vs. 6.5 ± 2.2 before and after GFD, p = 0.001). 98 patients underwent the gluten challenge and 28 (all females, mean age 38.9 ± 12.7 years, BMI 22.0 ± 2.9) reported a symptomatic relapse and deterioration of quality of life. No parameters were found to be statistically associated with positivity to the challenge. However, 14 patients responded to the placebo ingestion. Taking into account this finding, about 14% of patients responding to gluten withdrawal showed a symptomatic relapse during the gluten challenge. This group is suspected to have NCGS.

Diagnosis of gluten related disorders: Celiac disease, wheat allergy and non-celiac gluten sensitivity

Cereal crops and cereal consumption have had a vital role in Mankinds history. In the recent years gluten ingestion has been linked with a range of clinical disorders. Gluten-related disorders have gradually emerged as an epidemiologically relevant phenomenon with an estimated global prevalence around 5%. Celiac disease, wheat allergy and non-celiac gluten sensitivity represent different gluten-related disorders. Similar clinical manifestations can be observed in these disorders, yet there are peculiar pathogenetic pathways involved in their development. Celiac disease and wheat allergy have been extensively studied, while non-celiac gluten sensitivity is a relatively novel clinical entity, believed to be closely related to other gastrointestinal functional syndromes. The diagnosis of celiac disease and wheat allergy is based on a combination of findings from the patients clinical history and specific tests, including serology and duodenal biopsies in case of celiac disease, or laboratory and functional assays for wheat allergy. On the other hand, non-celiac gluten sensitivity is still mainly a diagnosis of exclusion, in the absence of clear-cut diagnostic criteria. A multimodal pragmatic approach combining findings from the clinical history, symptoms, serological and histological tests is required in order to reach an accurate diagnosis. A thorough knowledge of the differences and overlap in clinical presentation among gluten-related disorders, and between them and other gastrointestinal disorders, will help clinicians in the process of differential diagnosis.

Bread wheat gliadin cytotoxicity: a new three-dimensional cell model.

Background: In an attempt to clarify the role of gliadin toxicity in the pathogenesis of gluten intolerance (celiac disease), previous in vitro studies have been based on two‐dimensional human cell cultures. However, the specific morphological and biochemical properties of in vivo tissue are better maintained in three‐dimensional cell cultures (multicellular spheroids, MCS). The aim of this study was to develop a three‐dimensional in vitro model to investigate the effects of gliadin on epithelial cells and broaden our understanding of the early tissue damage occurring in celiac disease. Methods: The three‐dimensionally growing Lovo cell line was exposed to increasing concentrations of peptic‐tryptic‐digested bread wheat gliadin (from 125 to 1000u2005μg/mL) for 7 days in order to evaluate cell viability (colony‐forming assay), and at the standard concentration of 500u2005μg/mL for 7 days in order to evaluate MCS diameters, volumes and cell morphology using light and electron microscopy. Results: In comparison with the controls, the cell viability of the gliadin‐treated MCS was significantly reduced (20–80%), but there was no difference in size. Various degrees of cell damage (autophagic vacuoles and intra‐cytoplasmic lipid‐like droplets) were detected by both light and electron microscopy. Conclusion: This is the first study investigating the effects of gliadin on MCS. Lovo MCS seem to be responsive to gliadin exposure, thus confirming previous results obtained using two‐dimensional cell cultures. The data suggest that three‐dimensional cell cultures may be useful in broadening our understanding of some of the early effects of gliadin peptides on epithelial cells.

Immunological effects of transglutaminase-treated gluten in coeliac disease

Coeliac disease pathogenesis is characterized by an immune response triggered, in genetically predisposed subjects, by ingested gluten and its withdrawal from the diet is the only available therapy. However, enzymatic modification of gluten through the insertion of lysine to avoid antigen presentation could represent a new therapeutical approach for patients. Sixty-six duodenal biopsies from 17 coeliac patients were cultured for 48 h with gluten or enzymatically-modified gluten (treated with human recombinant transglutaminase type 2 or bacterial transglutaminase, with or without lysine). Interferonγ, anti endomisium and anti transglutaminase IgA antibodies, lactate dehydrogenase and transglutaminase activity were measured in the culture medium. Transglutaminase type 2 expression was evaluated on biopsies by immunohistochemistry. Gluten and transglutaminase-treated gluten increased by 13-15 fold interferon γ release, as well as antibodies, transglutaminase activity, and the immunohistochemical expression of transglutaminase type 2. Addition of lysine to the enzymatic modification of gluten normalized interferon γ, antibodies, transglutaminase activity and immunohistochemical expression of transglutaminase type 2. Lactate dehydrogenase did not differ among the studied groups. Enzymatic modification of gluten by transglutaminase plus lysine prevents the immunologic effects on cultured duodenal biopsies from coeliac patients and could be tested as an alternative therapy in coeliac disease.

Non-celiac gluten sensitivity: Time for sifting the grain

In the last few years, a new nomenclature has been proposed for the disease induced by the ingestion of gluten, a protein present in wheat, rice, barley and oats. Besides celiac disease and wheat allergy, the most studied forms of gluten-related disorders characterized by an evident immune mechanism (autoimmune in celiac disease and IgE-mediated in wheat allergy), a new entity has been included, apparently not driven by an aberrant immune response: the non-celiac gluten sensitivity (NCGS). NCGS is characterized by a heterogeneous clinical picture with intestinal and extraintestinal symptoms arising after gluten ingestion and rapidly improving after its withdrawal from the diet. The pathogenesis of NCGS is largely unknown, but a mixture of factors such as the stimulation of the innate immune system, the direct cytotoxic effects of gluten, and probably the synergy with other wheat molecules, are clues for the complicated puzzle. In addition, the diagnostic procedures still remain problematic due to the absence of efficient diagnostic markers; thus, diagnosis is based upon the symptomatic response to a gluten-free diet and the recurrence of symptoms after gluten reintroduction with the possibility of an important involvement of a placebo effect. The temporary withdrawal of gluten seems a reasonable therapy, but the timing of gluten reintroduction and the correct patient management approach are have not yet been determined.

Beneficial effects of treatment with transglutaminase inhibitor cystamine on the severity of inflammation in a rat model of inflammatory bowel disease.

Inflammatory bowel disease (IBD) represents a socially and clinically relevant disorder, characterized by intestinal chronic inflammation. Cystamine (CysN) is a multipotent molecule with healthy effects and, moreover, it is an inhibitor of transglutaminases (TGs), including the TG type 2 (TG2), an enzyme with pleiotropic functions, involved in different pathways of inflammation and central in the pathogenesis of some human disorders as the IBD. Our aim was to evaluate the effect of CysN in an IBD rat model. A total of 30 rats were divided into 4 groups: controls without treatment (CTR; n=7); receiving the 2,4,6-trinitrobenzene sulfonic acid enema (TNBS group; n=8); treated with TNBS enema plus oral CysN (TNBS–CysN group; n=8); treated with CysN (CysN group; n=7). After killing, bowel inflammation was evaluated applying specific scores. TG activity, TG2 and isopeptide bond immunohistochemical expression, and tumor necrosis factor-α (TNF-α) were evaluated in the colonic tissue, such as interleukin-6 (IL-6) serological levels (ELISA). TG2 was also evaluated on the luminal side of the colon by immunoautoradiography. Colonic samples from IBD patients were compared with animal results. TNBS–CysN group developed a less severe colitis compared with the TNBS group (macroscopic score 0.43±0.78 vs 3.28±0.95, microscopic score 6.62±12.01 vs 19.25±6.04, P<0.05, respectively) associated with a decrease of TG activity, TG2 and isopeptide bond immunohistochemical expression, TNF-α and IL-6 levels. No statistically significant differences were found between CysN and CTR groups. The colonic immunolocalization of TG2 was comparable in humans affected by IBD and TNBS-administered animals. This is the first demonstration that treatment with a CysN has an anti-inflammatory effect, reducing severity of colitis in a rat model. CysN could be tested as a possible treatment or co-treatment in IBD therapeutic trials.

Increased Mercury Levels in Patients with Celiac Disease following a Gluten-Free Regimen

Background and Aim. Although mercury is involved in several immunological diseases, nothing is known about its implication in celiac disease. Our aim was to evaluate blood and urinary levels of mercury in celiac patients. Methods. We prospectively enrolled 30 celiac patients (20 treated with normal duodenal mucosa and 10 untreated with duodenal atrophy) and 20 healthy controls from the same geographic area. Blood and urinary mercury concentrations were measured by means of flow injection inductively coupled plasma mass spectrometry. Enrolled patients underwent dental chart for amalgam fillings and completed a food-frequency questionnaire to evaluate diet and fish intake. Results. Mercury blood/urinary levels were 2.4 ± 2.3/1.0 ± 1.4, 10.2 ± 6.7/2.2 ± 3.0 and 3.7 ± 2.7/1.3 ± 1.2 in untreated CD, treated CD, and healthy controls, respectively. Resulting mercury levels were significantly higher in celiac patients following a gluten-free diet. No differences were found regarding fish intake and number of amalgam fillings. No demographic or clinical data were significantly associated with mercury levels in biologic samples. Conclusion. Data demonstrate a fourfold increase of mercury blood levels in celiac patients following a gluten-free diet. Further studies are needed to clarify its role in celiac mechanism.

Enteroscopy for the early detection of small bowel tumours in at-risk celiac patients

BACKGROUNDnA subset of celiac patients shows a high risk for small bowel malignancies.nnnAIMSnTo select celiac patients considered at risk and evaluate the diagnostic yield of enteroscopy in this context.nnnMETHODSnCeliac patients were enrolled from a tertiary referral centre during the period June 2011-June 2013, based on the following criteria: (i) patients diagnosed when aged 50+ and with poor response to gluten-free dieting; (ii) low dietary compliance; (iii) alarm symptoms. The patients underwent small bowel capsule endoscopy and/or double-balloon enteroscopy. Control populations were represented by the 165 non-celiac patients undergoing capsule endoscopy for obscure gastrointestinal bleeding, and the 815,362-strong population of the Italian province of Varese as a registered cohort.nnnRESULTSnFifty-three patients (19% males, mean age 43.6±17.4 years) were evaluated. Two jejunal adenocarcinomas and one ileal neuro-endocrine tumour were diagnosed by enteroscopy (the diagnostic yield for malignancies in the selected population being 5.7%). In the non-celiac controls the detection rate of small bowel tumours by capsule endoscopy was 0.6% (P=0.04). When compared to the registered population, the relative risk for intestinal malignancy was 1282 (95% CI, 407-4033; P<0.0001).nnnCONCLUSIONSnCapsule endoscopy and double-balloon enteroscopy can be considered for early disease management of a subset of celiac patients.

Isolation and culture of fibroblasts from endoscopic duodenal biopsies of celiac patients.

BackgroundFibroblasts are actually considered pivotal in inflammation and tissue remodelling process and for these reasons they are involved in the pathogenesis of autoimmune disorders such as celiac disease. Investigations to define the role of fibroblasts in celiac diseases are obstructed by the absence of specific models. Our objective is to isolate and culture primary fibroblasts from endoscopic duodenal biopsies of celiac and non-celiac subjects, to analyze their growth patterns and the morphometric characteristics.Methods60 duodenal bioptic specimens from 20 celiac patients and 114 from 38 non-celiac subjects were mechanically chopped and enzymatically digested in order to obtain primary cell cultures. Growth patterns, karyotype (Q-banding analysis), expression of typing proteins (fibroblast surface protein and cytokeratin 20) and morphometric parameters (diameters and their ratio, perimeter, area and perimeter/area ratio at computerised image analysis) were investigated on cultured cells.ResultsPrimary cells were successfully cultured in 78% of the collected duodenal biopsies. Cultured cells, expressing the fibroblast surface protein, were negative for cytokeratine 20 and maintained a normal kariotype. Cells grew slowly without differences between the celiac and the non celiac group. Morphometric analysis of celiac fibroblasts revealed significantly increased dimensions, with a preserved diameters ratio, and a reduced perimeter/area ratio.ConclusionFor the first time this study demonstrates the feasibility of culturing primary fibroblast cell from endoscopic duodenal biopsies in celiac and non-celiac subjects, opening a new window of opportunity in studies intended to establish the role of fibroblasts as a possible partaker in the pathogenesis of the celiac mucosal damage.

Histological evaluation of duodenal biopsies from coeliac patients: the need for different grading criteria during follow-up

BackgroundCoeliac disease is characterised by villous atrophy, which usually normalises after gluten withdrawal. Sometimes the revaluation of duodenal histology is required during follow-up, even if the methodology for comparing duodenal histology before and after introducing a gluten-free diet is not yet established. Our aim was to evaluate a novel criterion to compare duodenal histology in coeliac disease before and after gluten withdrawal.MethodsDuodenal biopsies from coeliac patients were retrospectively reviewed to compare duodenal histology at diagnosis and after at least one year on a gluten-free diet. Two different methods were used: the first was represented by the classical Marsh-Oberhuber score, the second compared the areas covered by each Marsh-Oberhuber grade and expressed as percentages, the final grade being calculated from the analysis of ten power fields per duodenal biopsy.ResultsSixty-nine patients (17 males 52 females, age at diagnosis 36u2009±u200915xa0years) who underwent duodenal biopsies, were considered. According to the classical Marsh-Oberhuber scale, 32 patients did not present atrophy during follow-up while 37 showed duodenal atrophy, among whom 26 improved the grade of severity and 11 retained the same one. Of these latter, according to the second method, eight patients were considered improved, two showed a worsened duodenal damage and only one remained unchanged; the evaluation changed in 91xa0% of cases.ConclusionsThe proposed semi-quantitative approach (i.e. the second method) for the evaluation of histology at follow-up provides additional information about the progression/regression of the mucosal damage.