Review
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 21, 2021; 27(43): 7446-7461
Published online Nov 21, 2021. doi: 10.3748/wjg.v27.i43.7446
Overview of the microbiota in the gut-liver axis in viral B and C hepatitis
Maria Adriana Neag, Andrei Otto Mitre, Adrian Catinean, Anca Dana Buzoianu
Maria Adriana Neag, Anca Dana Buzoianu, Department of Pharmacology, Toxicology and Clinical Pharmacology, Iuliu Hatieganu University of Medicine and Pharmacy of Cluj-Napoca, Cluj-Napoca 400337, Romania
Andrei Otto Mitre, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy of Cluj-Napoca, Cluj-Napoca 400012, Romania
Adrian Catinean, Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy of Cluj-Napoca, Cluj-Napoca 400006, Romania
Author contributions: Catinean A and Neag MA contributed to conceptualization; Catinean A, Neag MA and Mitre AO contributed to methodology and formal analysis; Mitre AO, Neag MA contributed to data curation; Catinean A, Neag MA, Mitre AO and Buzoianu AD wrote the original draft, reviewed and edited the manuscript; Buzoianu AD, Neag MA and Catinean A contributed to supervision.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: Andrei Otto Mitre, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy of Cluj-Napoca, 8. Babes Street, Cluj-Napoca 400012, Romania. andrei.otto.mitre@elearn.umfcluj.ro
Received: March 17, 2021
Peer-review started: March 17, 2021
First decision: August 9, 2021
Revised: August 13, 2021
Accepted: November 2, 2021
Article in press: November 2, 2021
Published online: November 21, 2021
Processing time: 245 Days and 16.5 Hours
Abstract

Viral B and C hepatitis are a major current health issue, both diseases having a chronic damaging effect on the liver and its functions. Chronic liver disease can lead to even more severe and life-threatening conditions, such as liver cirrhosis and hepatocellular carcinoma. Recent years have uncovered an important interplay between the liver and the gut microbiome: the gut-liver axis. Hepatitis B and C infections often cause alterations in the gut microbiota by lowering the levels of ‘protective’ gut microorganisms and, by doing so, hinder the microbiota ability to boost the immune response. Treatments aimed at restoring the gut microbiota balance may provide a valuable addition to current practice therapies and may help limit the chronic changes observed in the liver of hepatitis B and C patients. This review aims to summarize the current knowledge on the anato-functional axis between the gut and liver and to highlight the influence that hepatitis B and C viruses have on the microbiota balance, as well as the influence of treatments aimed at restoring the gut microbiota on infected livers and disease progression.

Keywords: Viral B hepatitis; Viral C hepatitis; Gut-liver axis; Immunomodulation; Lipopolysaccharides; Short-chain fatty acids

Core Tip: We have provided an overview of the mechanisms involved in the immunomodulation of the gut-liver axis. We highlight the mechanisms by which hepatitis B virus and hepatitis C virus infections influence the microbiota and how in turn these changes affect the liver pathology. We have also looked at the current treatment options and their influence on the intestinal microflora.