Blurring the picture in leaky gut research: how shortcomings of zonulin as a biomarker mislead the field of intestinal permeability
Lucas Massier, Rima Chakaroun, Péter Kovács, John T. Heiker
Abstract
With great interest we read the work by Talley et al 1 reporting the inadequacy of zonulin as a biomarker due to its failure to identify the irritable bowel syndrome, functional dyspepsia and non-coeliac wheat sensitivity. Zonulin as a biomarker is highly disputed.2 A recent study showed that zonulin-mediated intestinal barrier integrity is an important mechanism by which gut microbial dysbiosis affects the transition from asymptotic autoimmunity to inflammatory disease associated with increased circulating zonulin in patients with arthritis.3 In all of these studies, zonulin measurements are based on commercial ELISA. There is no doubt about the clinical relevance of studies addressing the relation between intestinal permeability and inflammatory diseases. Zonulin, precisely pre-haptoglobin 2 (preHP2), was identified as a human homologue to a second Vibrio cholerae enterotoxin regulating tight junction permeability and subsequently has gained …