Assessment of markers of gut integrity and inflammation in non-celiac gluten sensitivity after a gluten free-diet

Purpose: Markers for gut integrity and inflammation have received increasing interest as intestinal permeability and innate immune system activation are suggested as possible pathophysiological mechanisms in non-celiac gluten sensitivity (NCGS). We aimed to assess relevant biomarkers in NCGS by analyzing serum levels of gut integrity and permeability markers, pro-inflammatory cytokines and antigliadin IgG in patients with suspected NCGS on a gluten-free diet (GFD), and compare them to serum levels in patients with irritable bowel syndrome (IBS) and healthy controls (HC). Patients and Methods: Serum samples collected from patients with suspected NCGS on a GFD (n=20, 14 women, 21– 62 years), IBS (n=20, 16 women, 24– 67 years) and HC (n=20, 14 women, 21– 54 years) were analyzed. IBS severity scoring system (IBS-SSS) was applied to evaluate gastrointestinal symptoms. Results: The IBS-SSS score was higher in subjects with suspected NCGS and IBS patients compared to HC (p< 0.0001). No significant differences were found in the serum levels of any of the gut integrity and permeability markers, cytokines or antigliadin IgG antibodies between the three groups. However, positive correlations were observed between claudin-1 and i-FABP, and between claudin-1 and antigliadin IgG antibodies. Conclusion: No differences in serum levels of gut integrity and permeability markers, pro-inflammatory cytokines or antigliadin IgG antibodies were found among patients with suspected NCGS on a GFD, IBS and HC