Partially hydrolyzed guar gum attenuates the symptoms of SARS-CoV-2 infection through gut microbiota modulation in an animal model.

The coronavirus disease 2019 (COVID-19) pandemic has caused worldwide health issues. Although several vaccines have been developed, it is still difficult to prevent and reduce the inflammation caused by the infection. Studies have shown that there are correlations between the gut environment and severity of symptoms caused by SARS-CoV-2 infection. Several gut metabolites produced by the gut microbiota such as SCFAs and the secondary bile acid UDCA are reported to improve the survival rate of the host after viral infection in an animal model through modulation of the host immune system. Therefore, in this study, we attempted to use the prebiotic dietary fiber PHGG to modulate the gut microbiome and intestinal metabolites for improvement of host survival rate after SARS-CoV-2 infection in a Syrian hamster model. We were able to show that PHGG significantly improved the host survival rate and body weight reduction. Analysis of the gut microbiome, serum, and intestinal metabolites revealed that PHGG significantly increased the concentrations of several intestinal SCFAs, fecal secondary bile acids, and serum secondary bile acids. Furthermore, several microbial species and metabolites identified in this study are consistent with reports in humans. Taken together, our data suggest that PHGG is a candidate prebiotic food for reducing the morbidity of COVID-19.