Human gut microbiota from hepatitis B virus-infected individuals is associated with reduced triglyceride level in mice: faecal transplantation study

Abstract

Background: Chronic hepatitis B virus (HBV) infection is associated with a reduced risk of dyslipidaemia. Using a human faecal transplant mouse model, we compared changes in gut microbiota and lipid profiles in mice transplanted with human faeces from HBV-infected and non-infected individuals. Methods: A total of 19 mice received human faecal microbiota transplantation (FMT) from four HBV-infected individuals and were categorised into the HBV-positive mice group, while 20 mice received FMT from four HBV-non-infected individuals and were categorised into the HBV-negative mice group. Serial changes in the gut microbiota and lipid levels were compared between the two subgroups during 6 weeks of post-FMT period. Results: In the analysis of gut microbiota in FMT mice, we observed a robust increase in alpha diversity and abundance of taxa related to lipid metabolism, including Akkermansia muciniphila in HBV-positive mice, compared to that in HBV-negative mice. Functional inference analysis revealed that the pathways involved in glycerolipid metabolism were more enriched in HBV-positive mice. At 5 weeks of post-FMT, the reduced triglyceride (TG) level was predominantly observed in HBV-positive mice, compared to that in HBV-negative mice. Conclusions: In the experimental FMT mouse model, we found that altered gut microbiota accompanied by HBV infection was associated with a robust increase in alpha diversity and butyrate producers, which resulted in areduced level of TG at 5 weeks post-FMT. This indicates that the reduced risk of dyslipidaemia in chronic HBV infection may be due to the altered gut microbiota accompanied by HBV infection.