Inhibition of hepatitis B virus by oxymatrine in vivo

AIM To investigate the anti-HBV effect of oxymatrine (oxy) in vivo. METHODS HBV transgenic mice were produced by micro-injection of a 4.2kb fragment containing the complete HBV genomes. Expression level of HBsAg and HBcAg in the transgenic mice liver was determined by immunohistochemical assay, RESULTS Four groups (6 mice in each group) were injected intraperitoneally with oxy at the dosage of 100,200, and 300 mg/kg or with saline once a day for 30 days. Both HBsAg and HBcAg were positive in livers of all the six mice in the control group (injected with saline), and were positive in livers of two mice in 100 mg/kg group and 300mg/kg group. In 200mg/kg group, HBsAg and HBcAg were negative in livers of all the six mice. Based on the results, 200 mg/kg is the ideal dosage to explore the effect of oxy at different time points. According to the oxy treatment time, mice were divided into four groups: 10 d, 20 d, 30 d and 60 d (4 mice in each group). Each mouse underwent liver biopsy two weeks before the treatment of oxy. Down- regulation of HBsAg and HBcAg appeared after treatment of oxymatrine for 10 d and 20 d, Dane- like particles disappeared after the treatment of oxy for 20d under electron microscopy, however, the expression level of HBsAg and HBcAg returned to normal 60 d later after oxy treatment. CONCLUSION oxymatrine can reduce the contents of HBsAg and HBcAg in transgenic mice liver, longer treatment time and larger dosage do not yield better effects.