Serum zonulin measured by enzyme-linked immunosorbent assay may not be a reliable marker of small intestinal permeability in healthy adults

Oana A Tatucu-Babet; Adrienne Forsyth; Emma Owen; Diana Navarro-Perez; Jessica Radcliffe; Devin Benheim; Himasha Mendis; Markandeya Jois; Catherine Itsiopoulos; Audrey C Tierney

doi:10.1016/j.nutres.2020.05.003

Serum zonulin measured by enzyme-linked immunosorbent assay may not be a reliable marker of small intestinal permeability in healthy adults

Nutr Res. 2020 Jun:78:82-92. doi: 10.1016/j.nutres.2020.05.003. Epub 2020 May 19.

Affiliations

¹ Department of Dietetics, Nutrition and Sport, La Trobe University, Melbourne, Australia. Electronic address: oana.tatucu@monash.edu.
² Department of Dietetics, Nutrition and Sport, La Trobe University, Melbourne, Australia.
³ Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, Australia.
⁴ Department of Dietetics, Nutrition and Sport, La Trobe University, Melbourne, Australia; Senior Scientist Group Nutrition, Immunity and Metabolism, Department of Nutrition and Gerontology, German Institute of Human Nutrition, Potsdam-Rehbruecke, Germany.
⁵ Metabolomics Australia, School of BioSciences, University of Melbourne, Parkville, Australia.
⁶ Department of Dietetics, Nutrition and Sport, La Trobe University, Melbourne, Australia; College of Science, Health, Engineering and Education, Murdoch University, Perth, Australia.
⁷ Department of Dietetics, Nutrition and Sport, La Trobe University, Melbourne, Australia; School of Allied Health and Health Implementation Science and Technology Research Centre, Health Research Institute, University of Limerick, Limerick, Ireland.

PMID: 32563954
DOI: 10.1016/j.nutres.2020.05.003

Abstract

The association between intestinal permeability (IP) and body composition remains unclear. The gold standard differential sugar-absorption test is arduous to complete, with zonulin being increasingly used as an independent biomarker of IP. This pilot study aimed to explore the association between small IP, zonulin concentrations, and body composition in healthy adults. The urinary lactulose-rhamnose ratio was used to measure small IP. Serum zonulin, lipopolysaccharide (LPS) and high-sensitivity C-reactive protein (hs-CRP) were analyzed in serum. Body composition was measured using dual-energy X-ray absorptiometry and anthropometric measurements were collected. In total, 34 participants were included (12 males, median age 28 years, body mass index 24 kg/m², waist circumference 77cm). No correlation was observed between the lactulose-rhamnose ratio and zonulin (r = -.016, P = .929). The lactulose-rhamnose ratio displayed a strong positive correlation with LPS (n 20, r = .536, P = .018) but did not correlate with body composition measures. Conversely, zonulin displayed a moderate positive correlation with waist circumference (r = .437, P = .042) in female participants and hs-CRP (r = .485, P = .004) in all participants. These findings raise important considerations for the measurement of small IP, warranting exploration in larger powered studies that address the limitations of the present study.

Keywords: L-R ratio; body composition; endotoxemia; inflammation; intestinal permeability; zonulin.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Body Composition
Body Mass Index
C-Reactive Protein / analysis
Enzyme-Linked Immunosorbent Assay
Female
Haptoglobins
Humans
Intestinal Mucosa / physiology*
Intestine, Small / physiology*
Lactulose / urine
Lipopolysaccharides / blood
Male
Permeability
Pilot Projects
Protein Precursors / blood*
Reproducibility of Results
Rhamnose / urine

Substances

Haptoglobins
Lipopolysaccharides
Protein Precursors
zonulin
Lactulose
C-Reactive Protein
Rhamnose