Review
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Dec 21, 2022; 28(47): 6689-6701
Published online Dec 21, 2022. doi: 10.3748/wjg.v28.i47.6689
Alterations of the gut microbiota in coronavirus disease 2019 and its therapeutic potential
Hui Xiang, Qi-Ping Liu
Hui Xiang, Department of Infectious Disease, Chongqing University Three Gorges Hospital, Chongqing 404100, China
Qi-Ping Liu, Department of Pulmonary and Critical Care Medicine, Chongqing University Three Gorges Hospital, Chongqing 404100, China
Author contributions: Xiang H and Liu QP contributed equally to this work; Xiang H drafted the manuscript; Xiang H and Liu QP edited the manuscript, conceived and supervised the work; all the authors have read and approved the final manuscript.
Conflict-of-interest statement: There is no conflict of interest associated with any of the senior author or other coauthors contributed their efforts in this manuscript.
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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Hui Xiang, MM, Doctor, Department of Infectious Disease, Chongqing University Three Gorges Hospital, No. 165 Xincheng Road, Chongqing 404100, China. xianghui9312@163.com
Received: September 18, 2022
Peer-review started: September 18, 2022
First decision: October 30, 2022
Revised: November 7, 2022
Accepted: November 22, 2022
Article in press: November 22, 2022
Published online: December 21, 2022
Abstract

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a serious threat to global health. SARS-CoV-2 infects host cells primarily by binding to angiotensin-converting enzyme 2, which is coexpressed in alveolar type 2 cells and gut epithelial cells. It is known that COVID-19 often presents with gastrointestinal symptoms and gut dysbiosis, mainly characterized by an increase in opportunistic pathogens and a decrease in beneficial commensal bacteria. In recent years, multiple studies have comprehensively explored gut microbiota alterations in COVID-19 and highlighted the clinical correlation between dysbiosis and COVID-19. SARS-CoV-2 causes gastrointestinal infections and dysbiosis mainly through fecal-oral transmission and the circulatory and immune pathways. Studies have shown that the gut microbiota and its metabolites can regulate the immune response and modulate antiviral effects. In addition, the gut microbiota is closely related to gastrointestinal symptoms, such as diarrhea, a common gastrointestinal symptom among COVID-19. Therefore, the contribution of the gut microbiota in COVID-19 should not be overlooked. Strategies targeting the gut microbiota via probiotics, prebiotics and fecal microbiota transplantation should be considered to treat this patient population in the future. However, the specific alterations and mechanisms as well as the contributions of gut microbiota in COVID-19 should be urgently further explored.

Keywords: COVID-19, SARS-CoV-2, Angiotensin-converting enzyme 2, Gut microbiota, Dysbiosis, Lung

Core Tip: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global health threat. SARS-CoV-2 infects host cells through binding to angiotensin-converting enzyme 2. COVID-19 patients exhibit gut dysbiosis. Here, the gut microbiota alterations in COVID-19 are summarized. The pathways and possible mechanisms of dysbiosis caused by SARS-CoV-2, as well as the impact of the gut microbiota and its metabolites on the inflammatory response and antiviral effects during the course of the disease are also described. Therefore, targeting the gut microbiota should be considered a promising strategy for COVID-19 prevention, treatment, and prognostic assessment.