Entecavir therapy reverses gut microbiota dysbiosis induced by hepatitis B virus infection in a mouse model

Chronic hepatitis B virus (HBV) infection is a global public health problem. The gut microbiota has been linked to pathogenesis of liver diseases induced by chronic HBV infection. This study established a recombinant adeno-associated virus serotype 8 (rAAV8)-mediated persistent HBV infection mouse model. Entecavir (ETV) treatment significantly decreased the HBV DNA load both in serum and the liver. The comparison of gut microbiota composition of rAAV8-HBV-infected mice and ETV-treated mice with healthy controls was carried out using 16S rDNA sequencing analysis of caecal content samples. The intestinal microbiota alpha diversity of rAAV8-HBV-infected mice decreased, and significantly restored after 4 weeks of ETV therapy. Blautia and Clostridium sensu stricto significantly decreased in rAAV8-HBV-infected mice and was negatively correlated with both HBsAg and HBeAg levels. On the contrary, the Butyricicoccus and Prevotellaceae NK3B31 groups exhibited positive correlation with HBsAg and HBeAg. Furthermore, it was observed that Akkermansia, a known gut barrier-protecting bacterium, significantly decreased in rAAV8-HBV-infected mice and was restored to the level of that in healthy controls after ETV therapy, while the abundance of Akkermansia was negatively correlated with HBV DNA load both in serum and the liver. Taken together, the results showed that dysbiosis of gut microbiota developed in the persistent HBV-infected mice and was effectively reversed by ETV treatment, shedding light on the mechanisms of gut microbiota on HBV-persistent infection and antiviral therapy.