鸭乙型肝炎病毒DNA聚合酶和逆转录酶在抗乙型肝炎病毒药物研究中的应用

Application of DHBV Polymerase and Reverse Transcriptase in the Evaluation of Anti-HBV Drugs

本实验改进了鸭乙型肝炎病毒(DHBV)复制复合体(RCs)的制备方法,研究了14种中药复方和单味药提取物及30种成分药对DHBV DNA、聚合酶(DNAP)和逆转录酶(RT)的抑制作用。发现小柴胡汤提取物对DHBV RT和DNAP有轻度抑制作用,其7味药提取物中,黄芩和半夏对RT的半数抑制浓度(IC50)分别为1.25和18.6mg/ml,黄芩对DNAP的IC50为0.925mg/ml。鸭体内实验证明,口服给予黄芩水煎剂(5g/kg,每日3次,共10天)可显著降低鸭血清中DHBV DNA水平。此外,虎杖提取物对RT的IC50为1.76mg/ml,鱼腥草素等9种成分药对RT有轻度抑制作用。

The method of DHBV replication complexes (RCs) purification was modified. In order to screen anti-HBV drugs from Chinese medicinal herbs, the inhibitory effects of the extracts of 14 Chinese recipes and herbs, 30 compounds isolated from Chinese herbs on DHBV DNA polymerase (DNAP)and reverse transcriptase (RT) have been studied. The results showed that extracts of Xiao Chai Hu Tang (Small Bupleurum decoction,小柴胡汤) inhibited DHBV DNAP and RT in less extent. Of the 7 herbs, the components of Xiao Chai Hu Tang, the extracts of S. baicalensis and P. ternata potently inhibited DHBV RT, their concentration of reducing enzyme activity by 50% (IC_(50)) was 1.25 and 1.6 mg/ml respectively. Furthermore, it has been proved that S. baicalensis inhibited DHBV DNA replication in ducklings. It also was found the extract of P. cuspidatum inhibited DHBV RT with IC_(50) of 1.76 mg/ml. Nine of thirty isolated compounds inhibited both DHBV DNAP and RT in less extent under high concentration, while others did not.