Herbal medicine in the treatment of COVID-19 based on the gut-lung axis

Abstract

Respiratory symptoms are most commonly experienced by patients in the early stages of novel coronavirus disease 2019 (COVID-19). However, with a better understanding of COVID-19, gastrointestinal symptoms such as diarrhea, nausea, and vomiting have attracted increasing attention. The gastrointestinal tract may be a target organ of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The intestinal microecological balance is a crucial factor for homeostasis, including immunity and inflammation, which are closely related to COVID-19. Herbal medicine can restore intestinal function and regulate the gut flora structure. Herbal medicine has a long history of treating lung diseases from the perspective of the intestine, which is called the gut-lung axis. The physiological activities of guts and lungs influence each other through intestinal flora, microflora metabolites, and mucosal immunity. Microecological modulators are included in the diagnosis and treatment protocols for COVID-19. In this review, we demonstrate the relationship between COVID-19 and the gut, gut-lung axis, and the role of herbal medicine in treating respiratory diseases originating from the intestinal tract. It is expected that the significance of herbal medicine in treating respiratory diseases from the perspective of the intestinal tract could lead to new ideas and methods for treatment.

Keywords

COVID-19 / Gut-lung axis / Gut microbiota / Herbal medicine / Respiratory disease / SARS-CoV-2

Conflict of interest statement

The authors declare no conflict of interest.

Funding

This work was supported by the Tianjin Science and Technology Program (22ZXGBSY00020).

Author contributions

Mei Wang, Qiaoyu He, and Xiaopeng Chen conceived and designed this review. Qiaoyu He, Xiaopeng Chen, Yumeng Shi, Qian Tang, and Hong Xing drafted this article. Mei Wang, Xiaopeng Chen, and Han Zhang revised the manuscript. All the authors read and approved the final manuscript.

Ethical approval of studies and informed consent

Not applicable.

Data availability

The data used to support the findings of this study are included in the article.

Acknowledgments

None.

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