The Differences between Gluten Sensitivity, Intestinal Biomarkers and Immune Biomarkers in Patients with First-Episode and Chronic Schizophrenia.
Journal of clinical medicine. 2020;9(11)
Plain language summary
Schizophrenia is a heterogeneous neuroimmune disorder with unknown mechanisms and aetiology. The goal of this clinical study was to compare and evaluate IgG and IgA sensitivity, inflammation, and gut integrity between 52 first episode Schizophrenia patients, 50 chronic Schizophrenia patients, and 60 healthy controls to explain whether there were any associations between these markers. Study results show that antigliadin IgG and IgA antibodies, as well as inflammatory markers such as hs-CRP and IL-6, were significantly higher in the first episodes of schizophrenia and chronic schizophrenia patients when compared to the healthy controls. Schizophrenia risk was 4-7% higher among those with elevated Antigliadin IgG and IgA antibody levels. In addition, smoking cigarettes has been shown to increase the risk of developing schizophrenia. Patients with chronic schizophrenia showed elevated levels of anti-Saccharomyces cerevisiae antibody and soluble CD14, indicating bacterial translocation and immune activation. To understand the mechanisms behind chronic Schizophrenia, which link inflammation, immune responses, and the gut-brain axis, further robust larger studies are necessary. The results of this study can be used by healthcare professionals to understand the relationship between intestinal permeability, inflammation, and food hypersensitivity.
Schizophrenia is a heterogeneous disorder without a fully elucidated etiology and mechanisms. One likely explanation for the development of schizophrenia is low-grade inflammation, possibly caused by processes in the gastrointestinal tract related to gluten sensitivity. The aims of this study were to: (1) compare levels of markers of gluten sensitivity, inflammation and gut permeability, and (2) determine associations between gluten sensitivity, inflammation, and intestinal permeability in patients with first-episode/chronic (FS/CS) schizophrenia and healthy individuals (HC). The total sample comprised 162 individuals (52 FS; 50 CS, and 60 HC). The examination included clinical variables, nutritional assessment, and serum concentrations of: high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), soluble CD14 (sCD14), anti-Saccharomyces cerevisiae antibody (ASCA), antigliadin antibodies (AGA) IgA/IgG, antibodies against tissue transglutaminase 2 (anti-tTG) IgA, anti-deamidated gliadin peptides (anti-DGP) IgG. A significant difference between groups was found in sCD14, ASCA, hs-CRP, IL-6 and AGA IgA levels. AGA IgG/IgA levels were higher in the FS (11.54%; 30.77%) and CS (26%; 20%) groups compared to HC. The association between intestinal permeability and inflammation in the schizophrenic patients only was noted. The risk for developing schizophrenia was odds ratio (OR) = 4.35 (95% confidence interval (CI 1.23-15.39) for AGA IgA and 3.08 (95% CI 1.19-7.99) for positive AGA IgG. Inflammation and food hypersensitivity reactions initiated by increased intestinal permeability may contribute to the pathophysiology of schizophrenia. The immune response to gluten in FS differs from that found in CS.
Is perceived intolerance to milk and wheat associated with the corresponding IgG and IgA food antibodies? A cross sectional study in subjects with morbid obesity and gastrointestinal symptoms.
BMC gastroenterology. 2018;18(1):22
Plain language summary
Dairy and gluten are the most common triggers of irritable bowel syndrome (IBS) in the general population. Food intolerance is generally detected by IgG antibodies, but the test is controversial. In this cross-sectional study, 97 obese subjects (82.4% women) were included, of which 72.1% had gastrointestinal symptoms, 35.7% had IBS, 31.4% had symptoms of milk intolerance, 28.6% had symptoms of wheat intolerance, and 15.7% had symptoms of intolerance to both milk and wheat. The study examined the association between IgA and IgG antibodies corresponding to milk and wheat in subjects with and without gastrointestinal issues and with and without perceptions of food sensitivity. The results of this study found no association between s-IgG and s-IgA antibodies and perceived food intolerances to milk and wheat among morbidly obese subjects. Although IgA against gliadin correlated with increased levels of zonulin, a marker of intestinal permeability, tight-junctional gut permeability inversely correlated with wheat intolerance. Furthermore, the study results revealed a significant correlation between hypothyroidism and IgG against wheat and a marginal correlation between hypothyroidism and IgG against gluten. Further robust research is needed to confirm these findings. Healthcare professionals can use the results of this study to understand the current developments and the controversy surrounding food intolerance testing.
BACKGROUND Serum IgG and IgA food antibodies have been used for dietary advice to subjects with gastrointestinal symptoms and perceived food intolerance, but the role of these antibodies in mediating intolerance is controversial. The present study investigated associations between perceived gastrointestinal intolerance to milk-or wheat and the corresponding s-IgG and s-IgA food antibodies in subjects with morbid obesity. METHODS Subjects with morbid obesity (BMI ≥ 40 kg/m2 or ≥35 kg/m2 with obesity-related complications) were included. Irritable Bowel Syndrome (IBS) was diagnosed based on the Rome III criteria. Severity of specific gastrointestinal symptoms were measured with the Gastrointestinal Symptom Rating Scale (GSRS)-IBS. S-IgG against cow's milk, cheese, wheat and gluten, and s-IgA against casein and gliadin were measured. RESULTS Ninety-seven subjects (80 females) with mean age 45 (SD 8.4) years were included, 70 had gastrointestinal complaints, 25 had IBS, and 22 and 20 reported milk- and wheat- intolerance respectively. There were no significant differences in serum concentrations or proportions of subjects above defined cut-off values for the antibodies between subjects with and without gastrointestinal complaints. In the group with gastrointestinal complaints, no significant differences were found between subjects with and without perceived food intolerance. Except for a significant correlation between IgG against cheese and GSRS-diarrhea (Rho: -0.25, P = 0.04), no significant correlations were found between the antibodies and type or degree of gastrointestinal symptoms, including IBS. CONCLUSIONS The study showed no associations between perceived milk or wheat intolerance and the corresponding s-IgG and s-IgA food antibodies in subjects with morbid obesity.