Observational Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 28, 2019; 25(4): 509-520
Published online Jan 28, 2019. doi: 10.3748/wjg.v25.i4.509
Intestinal permeability after Mediterranean diet and low-fat diet in non-alcoholic fatty liver disease
Marco Biolato, Fiorella Manca, Giuseppe Marrone, Consuelo Cefalo, Simona Racco, Giacinto A Miggiano, Venanzio Valenza, Antonio Gasbarrini, Luca Miele, Antonio Grieco
Marco Biolato, Giuseppe Marrone, Simona Racco, Giacinto A Miggiano, Antonio Gasbarrini, Luca Miele, Antonio Grieco, Department of Gastroenterological, Endocrine-Metabolic and Nefro-Urological Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome 00168, Italy
Fiorella Manca, Giacinto A Miggiano, Antonio Gasbarrini, Luca Miele, Institute of Special Medical Pathology and Medical Semeiotics, Università Cattolica del Sacro Cuore, Rome 00168, Italy
Consuelo Cefalo, Antonio Grieco, Institute of Internal Medicine and Geriatrics, Università Cattolica del Sacro Cuore, Rome 00168, Italy
Venanzio Valenza, Department of Image Diagnostics, Oncological Radiotherapy and Hematology Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome 00168, Italy
Venanzio Valenza, Nuclear Medicine Institute, Università Cattolica del Sacro Cuore, Rome 00168, Italy
Author contributions: Grieco A was the guarantor and designed the study. Biolato M, Marrone G, Cefalo C and Racco S participated in the acquisition, analysis, and interpretation of the data, and drafted the initial manuscript. Manca F and Miggiano GA designed the diets and managed all the nutritional aspects of the study. Valenza V performed intestinal permeability tests. Gasbarrini A and Miele L revised the article critically for important intellectual content.
Supported by the Italian Ministry of Education, University and Research (MIUR), scientific research programs of relevant national interest year 2010-2011, No. 2010C4JJWB.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of Catholic University of Sacred Heart (Rome, Italy).
Informed consent statement: All study participants provided informed written consent prior to study enrollment.
Conflict-of-interest statement: There are no conflicts of interest to report.
STROBE statement: The authors have checked the manuscript according to STROBE checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Marco Biolato, MD, PhD, Staff Physician, Liver Transplant Medicine, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, Rome 00168, Italy. marco.biolato@policlinicogemelli.it
Telephone: +39-6-30154469
Received: November 5, 2018
Peer-review started: November 5, 2018
First decision: December 20, 2018
Revised: January 14, 2019
Accepted: January 18, 2019
Article in press: January 18, 2019
Published online: January 28, 2019
Processing time: 83 Days and 17.3 Hours
Abstract
BACKGROUND

In non-alcoholic fatty liver disease (NAFLD), a high-fat or high-fructose diet increases intestinal permeability and promotes derangement of the gut-liver axis. We hypothesize that, diet could be able to modulate intestinal permeability in patients with NAFLD.

AIM

To detect diet-induced modification of intestinal permeability in patients with NAFLD undergoing a Mediterranean diet or a low-fat diet.

METHODS

The current study was a dietary intervention for non-diabetic, patients with biopsy-verified NAFLD and increased transaminases. A crossover design was employed: participants underwent 16 weeks of Mediterranean diet, 16 wk of free wash-out, and 16 weeks of low-fat diet. Both diets were hypocaloric and no consumption of supplements was allowed. All patients were followed bimonthly by a dietitian. Evaluations of clinical and metabolic parameters were completed at baseline and at the end of each dietary period. Intestinal permeability was assessed by chromium-51 ethylene diamine tetraacetate excretion testing (51Cr-EDTA).

RESULTS

Twenty Caucasian patients, 90% male, median age 43 years, body mass index (BMI) 30.9, with biopsy-verified NAFLD were enrolled. At the end of 16 weeks of a Mediterranean diet, a significant reduction in mean body weight (-5.3 ± 4.1 kg, P = 0.003), mean waist circumference (-7.9 ± 4.9 cm, P = 0.001), and mean transaminase levels [alanine aminotransferase (ALT) -28.3 ± 11.9 IU/L, P = 0.0001; aspartate aminotransferase (AST) -6.4 ± 56.3 IU/L, P = 0.01] were observed. These benefits were maintained after 16 wk of wash-out and also after 16 wk of low-fat diet, without further improvements. Fourteen of the 20 patients had intestinal permeability alteration at baseline (mean percentage retention of 51Cr-EDTA = 5.4%), but no significant changes in intestinal permeability were observed at the end of the 16 wk of the Mediterranean diet or 16 wk of the low-fat diet.

CONCLUSION

Mediterranean diet is an effective strategy for treating overweight, visceral obesity and serum transaminase in patients with NAFLD. If the Mediterranean diet can improve intestinal permeability in patients with NAFLD, it deserves further investigation.

Keywords: Liver steatosis; Gut-liver axis; Nutrition; Personalized medicine; Visceral obesity

Core tip: Diet, as well as intestinal microbiota, is a key regulator of intestinal permeability, the alteration of which is central in the derangement of the gut-liver axis. In patients with non-alcoholic fatty liver disease (NAFLD), intestinal permeability is increased, promoting translocation of bacteria-derived products into the portal circulation and increasing hepatic exposure to injurious substances that stimulate hepatic inflammation and fibrosis. In animal models, high-fat diet or high-fructose intake has been associated with increased gut permeability. The aim of this study was to detect diet-induced modification of intestinal permeability in non-diabetic patients with NAFLD undergoing a Mediterranean diet or a low-fat diet.