ABSTRACT
Abstract] Objective To investigate the in vivo therapeutic effects of an extract of herb medi-cines, YiGanQingDuKeLi, in combination with adefovir dipivoxil (ADV) on the rebound of duck hepatitis B virus ( DHBV) multiplication after withdrawal of ADV treatment.Methods Peking ducks were infected with DHBV positive serum samples for 7 days and then screened by SYBR Green real-time PCR.The ducks positive for DHBV were randomly divided into five groups including the model control group, the ADV treat-ment group, the herb treatment group, the high-dose combination therapy group and the low-dose combina-tion therapy group.The ducks in the ADV treatment and the herb treatment groups were respectively treated with distilled water and YiGanQingDuKeLi (1.2 g/ml) for 14 days after the treatment of ADV (0.25 mg/ml) for 21 days.The ducks in the high-dose group were treated with YiGanQingDuKeLi (1.2 g/ml) for 14 days after the combined treatment with high-dose YiGanQingDuKeLi (1.2 g/ml) and ADV (0.25 mg/ml) for 21 days.The ducks in the low-dose group were treated with YiGanQingDuKeLi (0.6 g/ml) for 14 days after the combined treatment with YiGanQingDuKeLi (0.6 g/ml) and ADV (0.125 mg/ml) for 21 days.Blood samples were collected from each duck via leg vein after 0, 7, 14 and 21 days of drug adminis-tration and after 7 and 14 days of drug withdrawal.The levels of DHBV-DNA, alanine aminotransferase ( ALT) and aspartate aminotransferase ( AST) in blood serum samples were detected.Results Compared with the model group, the levels of DHBV-DNA, ALT and AST in ducks from the herb treatment group and combined treatment groups were decreased before the discontinuation of ADV treatment ( P<0.05 or P<0.01).Moreover, the titers of DHBV-DNA in ducks treated with high doses of drugs were much lower than those from ADV treatment group.The levels of DHBV-DNA, ALT and AST in ducks treated with herb medi-cine and high doses of drugs remained at relatively low levels after the cessation of ADV treatment, but re-bounded significantly in ducks with ADV treatment.The levels of DHBV-DNA and ALT rebounded slightly in ducks treated with low doses of drugs as compared with those of ADV treatment group ( P<0.01 or P<0.05).Conclusion The treatment of YiGanQingDuKeLi in combination with ADV could inhibit not only the in vivo replication of DHBV, but also the rebound of DHBV multiplication after ADV withdrawal.