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World J Gastroenterol. Jul 7, 2017; 23(25): 4491-4499
Published online Jul 7, 2017. doi: 10.3748/wjg.v23.i25.4491
Eubiotic properties of rifaximin: Disruption of the traditional concepts in gut microbiota modulation
Francesca Romana Ponziani, Maria Assunta Zocco, Francesca D’Aversa, Maurizio Pompili, Antonio Gasbarrini
Francesca Romana Ponziani, Maria Assunta Zocco, Francesca D’Aversa, Maurizio Pompili, Antonio Gasbarrini, Internal Medicine, Gastroenterology and Hepatology Division, Agostino Gemelli Hospital, 00168 Rome, Italy
Author contributions: Ponziani FR, Zocco MA and D’Aversa F performed literature research, wrote the paper and approved the final version of the manuscript; Pompili M and Gasbarrini A approved the final version of the manuscript.
Conflict-of-interest statement: No potential conflicts of interest relevant to this article were reported.
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/
Correspondence to: Francesca Romana Ponziani, MD, Internal Medicine, Gastroenterology and Hepatology Division, Agostino Gemelli Hospital, largo Agostino Gemelli 8, 00168 Rome, Italy. francesca.ponziani@yahoo.it
Telephone: +39-347-1227242 Fax: +39-063-0156265
Received: February 25, 2017
Peer-review started: February 27, 2017
First decision: April 7, 2017
Revised: April 14, 2017
Accepted: May 19, 2017
Article in press: May 19, 2017
Published online: July 7, 2017
Processing time: 131 Days and 14.8 Hours
Abstract

Antibiotics are usually prescribed to cure infections but they also have significant modulatory effects on the gut microbiota. Several alterations of the intestinal bacterial community have been reported during antibiotic treatment, including the reduction of beneficial bacteria as well as of microbial alpha-diversity. Although after the discontinuation of antibiotic therapies it has been observed a trend towards the restoration of the original condition, the new steady state is different from the previous one, as if antibiotics induced some kind of irreversible perturbation of the gut microbial community. The poorly absorbed antibiotic rifaximin seem to be different from the other antibiotics, because it exerts non-traditional effects additional to the bactericidal/bacteriostatic activity on the gut microbiota. Rifaximin is able to reduce bacterial virulence and translocation, has anti-inflammatory properties and has been demonstrated to positively modulate the gut microbial composition. Animal models, culture studies and metagenomic analyses have demonstrated an increase in Bifidobacterium, Faecalibacterium prausnitzii and Lactobacillus abundance after rifaximin treatment, probably consequent to the induction of bacterial resistance, with no major change in the overall gut microbiota composition. Antibiotics are therefore modulators of the symbiotic relationship between the host and the gut microbiota. Specific antibiotics, such as rifaximin, can also induce eubiotic changes in the intestinal ecosystem; this additional property may represent a therapeutic advantage in specific clinical settings.

Keywords: Intestinal bacteria; Antibiotic; Rifaximin; Gut microbiota; Eubiosis; Dysbiosis; Gut microbiota modulation

Core tip: The traditional use of antibiotics in the clinical practice is to antagonize local or systemic infections. However, antibiotics induce several alterations of the gut microbiota, including the reduction of beneficial bacteria as well as of microbial diversity. Rifaximin is a non-absorbable antibiotic with broad-spectrum activity and non-traditional antimicrobial effects. Rifaximin has the potential to induce a positive modulation of the gut microbiota, favoring the growth of bacteria beneficial to the host without altering its overall composition. Therefore, rifaximin can be defined not only as an antibiotic but also as an “eubiotic”, namely a positive modulator of the gut ecosystem.