Hyperbaric oxygen augments susceptibility to C. difficile infection by impairing gut microbiota ability to stimulate the HIF-1α-IL-22 axis in ILC3

ABSTRACT

Hyperbaric oxygen (HBO) therapy is a well-established method for improving tissue oxygenation and is typically used for the treatment of various inflammatory conditions, including infectious diseases. However, its effect on the intestinal mucosa, a microenvironment known to be physiologically hypoxic, remains unclear. Here, we demonstrated that daily treatment with hyperbaric oxygen affects gut microbiome composition, worsening antibiotic-induced dysbiosis. Accordingly, HBO-treated mice were more susceptible to Clostridioides difficile infection (CDI), an enteric pathogen highly associated with antibiotic-induced colitis. These observations were closely linked with a decline in the level of microbiota-derived short-chain fatty acids (SCFAs). Butyrate, a SCFA produced primarily by anaerobic microbial species, mitigated HBO-induced susceptibility to CDI and increased epithelial barrier integrity by improving group 3 innate lymphoid cell (ILC3) responses. Mice displaying tissue-specific deletion of HIF-1 in RORγt-positive cells exhibited no protective effect of butyrate during CDI. In contrast, the reinforcement of HIF-1 signaling in RORγt-positive cells through the conditional deletion of VHL mitigated disease outcome, even after HBO therapy. Taken together, we conclude that HBO induces intestinal dysbiosis and impairs the production of SCFAs affecting the HIF-1α-IL-22 axis in ILC3 and worsening the response of mice to subsequent C. difficile infection.

KEYWORDS:

• Hyperbaric oxygen
• microbiota
• butyrate
• clostridioides difficile
• innate lymphoid cells
• ILC3
• HIF-1

Acknowledgments

We thank Dr. Rodrigo Otávio Silveira Silva from the Federal University of Minas Gerais for donating C. difficile strain RT078. We also appreciate the technical support and scientific discussions with our laboratory members and collaborators.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

JLF and MARV contributed substantially to the conception of the work. All authors substantially contributed to the acquisition, analysis, and interpretation of data for the manuscript and critically reviewed the manuscript for important intellectual content. JLF, LPP, and HCA performed key experiments. All authors approved the final version of this manuscript and agreed to be accountable for all aspects of the work, ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Funding acquisition and resources were provided by the SG, MC and MARV. MARV supervised this study.

Data availability statement

All the relevant data supporting these findings are available in this report. In particular, 16S sequencing data have been deposited in the NCBI BioProject: PRJNA900580.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/19490976.2023.2297872.

Additional information

Funding

This study was supported by the Pew Charitable Thrust, USA (#00035299), National Institutes of Health, USA (1R01DK126969-01), Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil (FAPESP, #2017/06577-9, 2018/15313-8), the National Council for Scientific and Technological Development, Brazil (CNPq), and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brazil (CAPES), Finance Code 001. M. C. was also supported by MIST (U01 AI095542).