ArticleEuropean archives of psychiatry and clinical neuroscience2021
Serum zonulin and claudin-5 levels in patients with schizophrenia.
Article in European archives of psychiatry and clinical neuroscience, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 38 papers, 2 of them syntheses that pooled it.
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The trial behind it
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Who cites it
38 citing papers in PubMed, 2 syntheses or guidelines pooled it, 64 citations in OpenAlex.
- Convergent blood-brain barrier breakdown in schizophrenia and autism spectrum disorders: a systematic review of preclinical animal models.Fluids and barriers of the CNS · 2026Pooled it
- Immune System Abnormalities in Schizophrenia: An Integrative View and Translational Perspectives.Frontiers in psychiatry · 2022Pooled it
- Probiotic Formulation for Patients With Bipolar or Schizophrenia Spectrum Disorder: A Double-Blind, Randomized Placebo-Controlled Trial.Schizophrenia bulletin · 2025Trial
- Investigation of Tight Junction Protein Alterations in ADHD: The Role of Claudin-5, β-Catenin and Paxillin.Journal of attention disorders · 2026Article
- Serum LBP and zonulin levels with brain MRS findings and gastrointestinal symptoms in schizophrenia and health.Brain, behavior, & immunity - health · 2026Article
- The role of tight junction proteins in the pathogenesis of schizophrenia.European archives of psychiatry and clinical neuroscience · 2026Review
- Elevated serum zonulin is associated with high attack frequency in hereditary angioedema: providing insight into the gut-angioedema axis.Orphanet journal of rare diseases · 2026Article
- Serum Claudin-5 and Peripheral Inflammation in Major Depressive Disorder: A Case-Control Study with Focus on Suicidal Ideation.Alpha psychiatry · 2026Article
- Brain endothelial homeostasis in psychiatric disorders: mechanisms, evidence, and translational opportunities.Frontiers in cellular neuroscience · 2026Review
- Serum Zonulin Levels in Patients with Heroin Addiction.Sisli Etfal Hastanesi tip bulteni · 2026Article
- Investigation of <italic>CLDN5</italic> Gene 3' Untranslated Region rs10314 Polymorphism and Protein Levels in Children and Adolescents with Attention-Deficit Hyperactivity Disorder: A Molecular and Clinical Correlation Study.Medical principles and practice : international journal of the Kuwait University, Health Science Centre · 2026Article
- Claudin proteins and hemorrhage severity in aneurysmal subarachnoid hemorrhage: Correlation with modified Fisher score but not functional outcome.Neurosurgical review · 2025Article
- Blood‑brain barrier dysfunction in schizophrenia: Mechanisms and implications (Review).International journal of molecular medicine · 2025Review
- The intersection of circadian rhythms and the blood-brain barrier with drug efficacy and delivery in neurological disorders.Advanced drug delivery reviews · 2025Review
- Claudin 5 Across the Vascular Landscape: From Blood-Tissue Barrier Regulation to Disease Mechanisms.Cells · 2025Review
- Evaluation of zonulin levels in patients with migraine.BMC neurology · 2025Article
- Blood-Brain Barrier Disruption in Schizophrenia: Insights, Mechanisms, and Future Directions.International journal of molecular sciences · 2025Review
- Is there a link between peripheral inflammation and blood brain barrier integrity in children with attention-deficit/hyperactivity disorder? A case-control study.BMC pediatrics · 2024Article
- Association of Plasma Claudin-5 with Age and Alzheimer Disease.International journal of molecular sciences · 2024Article
- Evaluation of serum zonulin and occludin levels in obsessive-compulsive disorder and the effect of major depressive disorder comorbidity.Frontiers in psychiatry · 2024Article
Corrections and comments
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Authors and funding
6 authors at 1 institution in 1 country.
Funding
Abstract
The aim of this research was to assess whether or not changes in the concentrations of serum zonulin and claudin-5 in patients with schizophrenia could have etiopathogenetic importance. In previous studies, the data regarding the relationship between intestinal and blood-brain barrier (BBB) permeability and the etiology of schizophrenia have been limited. In this study, we assumed that there may be a difference in serum zonulin and claudin-5 levels in patients with schizophrenia, which may affect the severity of the disease. Fifty schizophrenia patients and 50 healthy controls were included in this study. The patients were administered the Positive Symptoms Assessment Scale (SAPS) and Negative Symptoms Assessment Scale (SANS) to determine the severity of symptoms. Venous blood samples were collected, and the serum zonulin and claudin-5 levels were measured. The mean serum zonulin levels were significantly increased in patients with schizophrenia when compared to the control group. Serum claudin-5 levels were decreased in the schizophrenia patients when compared to the controls. The present study indicates that zonulin is increased and claudin-5 is decreased in patients with schizophrenia. These findings extend the existing knowledge on the dysregulation of intestinal permeability, especially zonulin, and BBB, especially claudin-5, and show that both proteins may be involved in the etiopathogenesis of schizophrenia.
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Registered trials
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