Combining Oxymatrine or Matrine with Lamivudine Increased Its Antireplication Effect against the Hepatitis B VirusIn Vitro

Some recent clinical reports have shown that the combination of oxymatrine, a phyto-derived drug, with lamivudine (3TC) could improve its curative effect against hepatitis B virus (HBV) infection. However, the experimental data in support of this combination strategy are lacking. In this study, we investigated the anti-HBV activity of the combination of 3TC and either oxymatrine or matrine on HepG2 2.2.15in vitro. The activities of the combination and the solo compound, each in different concentrations, were compared on the 3rd, 6th, and 9th experimental days. The cytotoxicity results showed that the nontoxic concentrations of both oxymatrine and matrine to HepG2 2.2.15 cells were 800 μg/mL. We found that the single use of oxymatrine below 100 μg/ml, matrine below 200 μg/ml, and 3TC below 30 μg/ml showed weak inhibitory effects on the secretion of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and HBV-DNA in culture media; the combination of 3TC (30 μg/ml) with oxymatrine (100 μg/ml) or matrine (100 μg/ml) showed significant inhibitory effects that were higher than or equivalent to the single use of 3TC at 100 μg/ml. The results provide a new impetus to develop novel, multicomponent anti-HBV drugs through the combination of natural products with nucleoside analogs to enhance their activity.

Ethanol Extract from Ampelopsis sinica Root Exerts Anti-Hepatitis B Virus Activity via Inhibition of p53 PathwayIn Vitro

Ampelopsis sinicaroot is widely used in Chinese folk medicine for treating liver disorders caused by the hepatitis B virus (HBV). The present study was performed in order to investigate the anti-HBV activity and mechanisms of the ethanol extract fromA. sinicaroot (EASR)in vitro.The antiviral activity of EASR was examined by detecting the levels of HBsAg, HBeAg and extracellular HBV DNAs in stable HBV-producing human hepatoblastoma HepG2 2.2.15 cells. We found that EASR effectively suppressed the secretion of HBsAg and HBeAg from HepG2 2.2.15 cells in a dose-dependent manner, and it also suppressed the amount of extracellular HBV DNA. After EASR treatment, the percentage of apoptotic cells was found to be significantly higher than that of control by flow cytometric analysis. A luciferase reporter gene assay was used to determine the effects of EASR on the activities of HBV promoters and intracellular signaling pathways. The results showed that EASR selectively inhibited the activities of HBV promoters (Cp, S1p and Fp) and the p53 signaling pathway in HepG2 cells significantly. These data indicate that EASR exerts anti-HBV effects via inhibition of HBV promoters and the p53-associated signaling pathway, which helps to elucidate the mechanism underlying the potential therapeutic value of EASR.

The Anti-Hepatitis B Virus Activity ofBoehmeria niveaExtract in HBV-Viremia SCID Mice

Boehmeria niveaextract (BNE) is widely used in southern Taiwan as a folk medicine for hepato-protection and hepatitis treatment. In previous studies, we demonstrated that BNE could reduce the supernatant hepatitis B virus (HBV) DNA in HBV-producing HepG2 2.2.15 cells. In the present study, we established an animal model of HBV viremia and used it to validate the efficacy of BNEin vivo. In this animal model, serum HBV DNA and HBsAg were elevated in accordance with tumor growth. To evaluate the anti-HBV activity of BNE, HBV-viremia mice were built up after one subcutaneous inoculation of HepG2 2.2.15 tumor cells in severe combined immunodeficiency mice over 13 days. The levels of serum HBV DNA were elevated around 105–106copies per milliliter. Both oral and intraperitoneal administration of BNE were effective at inhibiting the production of HBsAg and HBV DNA, whereas tumor growth was not affected by all test articles. Intraperitoneal administration of BNE appeared to have greater potential to inhibit serum HBV DNA levels compared with oral administration under the same dosage. Notably, reduced natural killer cell activity was also observed after high dosage of BNE administration, and this correlated with reduced serum HBV DNA. In conclusion, BNE exhibited potential anti-HBV activity in an animal model of HBV viremia.