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.
The Microbiota-Gut-Brain Axis in Neuropsychiatric Disorders: Pathophysiological Mechanisms and Novel Treatments.
Current neuropharmacology. 2018;16(5):559-573
Plain language summary
The connection between the microbiome in the gut and the brain is known as the gut-brain axis and may have implications in the development and treatment of brain disorders. This narrative review paper aimed to summarise the gut-brain axis and studies surrounding the use of gut microbiota in treatment for brain disorders. The authors first highlighted that the gut microbiota is individual and varies depending on the age of the host, with full development around the age of 3 years old. Diet, infections, the use of antibiotics and stress can all affect the gut-microbiota in what is termed dysbiosis. Studies in animals indicate that the gut-brain axis may be bidirectional with either aspect affecting the other. Stress may cause dysbiosis, affecting both digestion and the immune system. In turn the gut microbiota may affect the brain through the immune system, modulation of nerves, and through the production of signalling molecules. Several diseases of the brain may be influenced by the gut microbiota. Mood disorders, brain degeneration and childhood brain development disorders were all highlighted as having potential relationships with dysbiosis. The use of probiotics in chronic fatigue syndrome, schizophrenia, brain function and autism spectrum disorder were reviewed with positive results in chronic fatigue syndrome and brain function, however studies are lacking. It was concluded that gut microbiota may directly or indirectly affect brain disorders, however the role of probiotics as a treatment needs more research. This study could be used by healthcare professionals to understand the potential role of the gut microbiota in brain disorders.
BACKGROUND The human gut microbiome comprise a huge number of microorganisms with co-evolutionary associations with humans. It has been repeatedly revealed that bidirectional communication exists between the brain and the gut and involves neural, hormonal, and immunological pathways. Evidences from neuroscience researches over the past few years suggest that microbiota is essential for the development and maturation of brain systems that are associated to stress responses. METHOD This review provides that the summarization of the communication among microbiota, gut and brain and the results of preclinical and clinical studies on gut microbiota used in treatments for neuropsychiatric disorders. RESULT Recent studies have reported that diverse forms of neuropsychiatric disorders (such as autism, depression, anxiety, and schizophrenia) are associated with or modulated by variations in the microbiome, by microbial substrates, and by exogenous prebiotics, antibiotics, and probiotics. CONCLUSION The microbiota-gut-brain axis might provide novel targets for prevention and treatment of neuropsychiatric disorders. However, further studies are required to substantiate the clinical use of probiotics, prebiotics and FMT.