scholarly journals In Vitro Inhibition of Hepadnavirus Polymerases by the Triphosphates of BMS-200475 and Lobucavir

1998 ◽  
Vol 42 (12) ◽  
pp. 3200-3208 ◽  
Author(s):  
Maria Seifer ◽  
Robert K. Hamatake ◽  
Richard J. Colonno ◽  
David N. Standring
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Mammalian Cells ◽  
Hepatitis Virus ◽  
Kinetic Studies ◽  
Duck Hepatitis ◽  
B Virus ◽  
Very High

ABSTRACT The guanosine analogs BMS-200475 and lobucavir have previously been shown to effectively suppress propagation of the human hepatitis B virus (HBV) and woodchuck hepatitis virus (WHV) in 2.2.15 liver cells and in the woodchuck animal model system, respectively. This repression was presumed to occur via inhibition of the viral polymerase (Pol) by the triphosphate (TP) forms of BMS-200475 and lobucavir which are both produced in mammalian cells. To determine the exact mode of action, BMS-200475–TP and lobucavir-TP, along with several other guanosine analog-TPs and lamivudine-TP were tested against the HBV, WHV, and duck hepatitis B virus (DHBV) polymerases in vitro. Estimates of the 50% inhibitory concentrations revealed that BMS-200475–TP and lobucavir-TP inhibited HBV, WHV, and DHBV Pol comparably and were superior to the other nucleoside-TPs tested. More importantly, both analogs blocked the three distinct phases of hepadnaviral replication: priming, reverse transcription, and DNA-dependent DNA synthesis. These data suggest that the modest potency of lobucavir in 2.2.15 cells may be the result of poor phosphorylation in vivo. Kinetic studies revealed that BMS-200475–TP and lobucavir-TP competitively inhibit HBV Pol and WHV Pol with respect to the natural dGTP substrate and that both drugs appear to bind to Pol with very high affinities. Endogenous sequencing reactions conducted in replicative HBV nucleocapsids suggested that BMS-200475–TP and lobucavir-TP are nonobligate chain terminators that stall Pol at sites that are distinct yet characteristically two to three residues downstream from dG incorporation sites.

Effect of 3′-azido-3′-deoxythymidine on replication of duck hepatitis B virus in vivo and in vitro

1989 ◽  
Vol 29 (4) ◽  
pp. 244-248 ◽  
Author(s):  
Hideaki Haritani ◽  
Toshikazu Uchida ◽  
Yasunori Okuda ◽  
Toshio Shikata
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Duck Hepatitis B Virus ◽  
Duck Hepatitis ◽  
B Virus

scholarly journals Anti-Hepatitis B Virus Activity of Esculetin from Microsorium fortunei In Vitro and In Vivo

Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3475 ◽  
Author(s):  
Si-Xin Huang ◽  
Jun-Fei Mou ◽  
Qin Luo ◽  
Qing-Hu Mo ◽  
Xian-Li Zhou ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hepatitis B Surface Antigen ◽  
Antiviral Drug ◽  
Liver Carcinoma ◽  
Dependent Manner ◽  
Duck Hepatitis ◽  
B Virus

Coumarins are widely present in a variety of plants and have a variety of pharmacological activities. In this study, we isolated a coumarin compound from Microsorium fortunei (Moore) Ching; the compound was identified as esculetin by hydrogen and carbon spectroscopy. Its anti-hepatitis B virus (HBV) activity was investigated in vitro and in vivo. In the human hepatocellular liver carcinoma 2.2.15 cell line (HepG2.2.15) transfected with HBV, esculetin effecting inhibited the expression of the HBV antigens and HBV DNA in vitro. Esculetin inhibited the expression of Hepatitis B virus X (HBx) protein in a dose-dependent manner. In the ducklings infected with duck hepatitis B virus (DHBV), the levels of DHBV DNA, duck hepatitis B surface antigen (DHBsAg), duck hepatitis B e-antigen (DHBeAg), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) decreased significantly after esculetin treatment. Summing up the above, the results suggest that esculetin efficiently inhibits HBV replication both in vitro and in vivo, which provides an opportunity for further development of esculetin as antiviral drug.

Duck hepatitis B virus polymerase gene mutants associated with resistance to lamivudine have a decreased replication capacity in vitro and in vivo

2001 ◽  
Vol 34 (1) ◽  
pp. 114-122 ◽  
Author(s):  
Béatrice Seignères ◽  
Stéphanie Aguesse-Germon ◽  
Christian Pichoud ◽  
Isabelle Vuillermoz ◽  
Catherine Jamard ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Replication Capacity ◽  
Polymerase Gene ◽  
Duck Hepatitis B Virus ◽  
Duck Hepatitis ◽  
B Virus

scholarly journals Interaction between ganciclovir and foscarnet as inhibitors of duck hepatitis B virus replication in vitro.

1996 ◽  
Vol 40 (5) ◽  
pp. 1180-1185 ◽  
Author(s):  
G Civitico ◽  
T Shaw ◽  
S Locarnini
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hbv Dna ◽  
Duck Hepatitis ◽  
Chronic Hepatitis B Virus ◽  
B Virus ◽  
Dose Limiting Toxicity

Safe and effective treatments for chronic hepatitis B virus (HBV) infection have yet to be developed. Both ganciclovir (9-[1,3-dihydroxy-2-propoxymethyl]guanine) and foscarnet (trisodium phosphonoformate hexahydrate) are potent inhibitors of hepadnavirus replication when used individually in vitro and in vivo. However, the clinical usefulness of each drug is reduced by dose-limiting toxicity, especially during long-term monotherapy. Here we demonstrate additive inhibition of duck HBV DNA replication in cultures of primary duck hepatocytes congenitally infected with duck HBV by combinations of ganciclovir and foscarnet at low, clinically achievable concentrations. These results suggest that the effects of ganciclovir and foscarnet against HBV may be additive in vivo.

scholarly journals Inhibition of duck hepatitis B virus replication by 2',3'-dideoxy-3'-fluoroguanosine in vitro and in vivo.

1996 ◽  
Vol 40 (3) ◽  
pp. 792-794 ◽  
Author(s):  
P Hafkemeyer ◽  
A Keppler-Hafkemeyer ◽  
M A al Haya ◽  
M von Janta-Lipinski ◽  
E Matthes ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Strong Inhibitor ◽  
Duck Hepatitis B Virus ◽  
Duck Hepatitis ◽  
B Virus ◽  
Dependent Inhibition ◽  
Dose Dependent Inhibition

The antiviral activity of 2',3'-dideoxy-3'-fluoroguanosine (FdG) or its triphosphate was evaluated in the duck hepatitis B virus (DHBV) system in vitro and in vivo. In primary DHBV-infected hepatocytes FdG results in a dose-dependent inhibition of viral replication with a nearly complete inhibition at a concentration of 1 microM. Also in vivo, FdG treatment of DHBV-infected ducklings reduces DHBV DNA replication by more than 90%. These data demonstrate that FdG is a strong inhibitor of DHBV replication in vitro and in vivo.

scholarly journals In vivo antiviral activity and pharmacokinetics of (-)-cis-5-fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine in woodchuck hepatitis virus-infected woodchucks.

1997 ◽  
Vol 41 (10) ◽  
pp. 2076-2082 ◽  
Author(s):  
J M Cullen ◽  
S L Smith ◽  
M G Davis ◽  
S E Dunn ◽  
C Botteron ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Treatment Group ◽  
Hepatitis B ◽  
Dna Polymerase ◽  
Hepatitis Virus ◽  
Woodchuck Hepatitis Virus ◽  
Normal Ranges ◽  
B Virus

The (-) enantiomer of cis-5-fluoro-1l-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine [(-)-FTC)], a substituted oxathiolane compound with anti-hepatitis B virus activity in vitro, was assessed for its efficacy in woodchucks with naturally acquired woodchuck hepatitis virus (WHV) infection. Pharmacokinetics and in vitro anabolism were also determined. (-)-FTC was anabolized to the 5'-triphosphate in a dose-related fashion, reaching a maximum concentration at about 24 h in cultured woodchuck hepatocytes. Following administration of a dose of 10 mg/kg of body weight intraperitoneally (i.p.), the clearance of (-)-FTC from plasma was monoexponential, the terminal half-life was 3.76 +/- 1.4 h, and the systemic clearance was 0.12 +/- 0.06 liters/h/kg. The antiviral efficacy of (-)-FTC in the woodchuck model was assessed by quantitation of serum WHV DNA levels and by WHV particle-associated DNA polymerase activity at two dosages, 30 and 20 mg/kg given i.p. twice daily (b.i.d.), respectively. The level of WHV DNA in serum was reduced 20- to 150-fold (average, 56-fold) in the 30-mg/kg-b.i.d. treatment group and 6- to 49-fold (average, 27-fold) in the 20-mg/kg-b.i.d. treatment group. Viral DNA polymerase levels diminished accordingly. One week after treatment was discontinued, WHV levels returned to pretreatment levels in both studies. These animals were biopsied before and following treatment with 30 mg of (-)-FTC per kg. Their livers were characterized by a mild increase in cytoplasmic lipid levels, but this change was not associated with altered liver enzyme levels. Serum chemistry and hematology results were within the normal ranges for all treated animals. We conclude that (-)-FTC is a potent antihepadnaviral agent and that it has no detectable toxic effects in woodchucks when given for up to 25 days. Further development of (-)-FTC as an anti-hepatitis B virus therapy for patients is warranted.

scholarly journals In Vitro Antihepadnaviral Activities of Combinations of Penciclovir, Lamivudine, and Adefovir

2000 ◽  
Vol 44 (3) ◽  
pp. 551-560 ◽  
Author(s):  
Danni Colledge ◽  
Gilda Civitico ◽  
Stephen Locarnini ◽  
Tim Shaw
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hbv Infection ◽  
Immunomodulatory Activity ◽  
Clinical Use ◽  
Duck Hepatitis ◽  
B Virus ◽  
The Individual

ABSTRACT Penciclovir {9-[2-hydroxy-1-(hydroxymethyl)-ethoxymethyl]guanine [PCV]}, lamivudine ([−]-β-l-2′,3′-dideoxy-3′-thiacytidine [3TC]), and adefovir (9-[2-phosphonylmethoxyethyl]-adenine [PMEA]) are potent inhibitors of hepatitis B virus (HBV) replication. Lamivudine has recently received approval for clinical use against chronic human HBV infection, and both PCV and PMEA have undergone clinical trials against HBV in their respective prodrug forms {famciclovir and adefovir dipivoxil [bis-(POM)-PMEA]}. Since multidrug combinations are likely to be used to control HBV infection, investigation of potential interactions between PCV, 3TC, and PMEA is important. Primary duck hepatocyte cultures which were either acutely or congenitally infected with the duck hepatitis B virus (DHBV) were used to investigate in vitro interactions between PCV, 3TC, and PMEA. Here we show that the anti-DHBV effects of all the combinations containing PCV, 3TC, and PMEA are greater than that of each of the individual components and that their combined activities are approximately additive or synergistic. These results may underestimate the potential in vivo usefulness of PMEA-containing combinations, since there is evidence that PMEA has immunomodulatory activity and, at least in the duck model of chronic HBV infection, is capable of inhibiting DHBV replication in cells other than hepatocytes, the latter being unaffected by treatment with either PCV or 3TC. Further investigation of the antiviral activities of these drug combinations is therefore required, particularly since each of the component drugs is already in clinical use.

Effects of Phyllanthus plant extracts on duck hepatitis B virus in vitro and in vivo

1992 ◽  
Vol 18 (2) ◽  
pp. 127-138 ◽  
Author(s):  
Andrew Shead ◽  
Karen Vickery ◽  
Aniko Pajkos ◽  
Robert Medhurst ◽  
John Freiman ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Plant Extracts ◽  
Duck Hepatitis B Virus ◽  
Duck Hepatitis ◽  
B Virus

scholarly journals Nucleic Acid Polymers Prevent the Establishment of Duck Hepatitis B Virus InfectionIn Vivo

2013 ◽  
Vol 57 (11) ◽  
pp. 5299-5306 ◽  
Author(s):  
Faseeha Noordeen ◽  
Andrew Vaillant ◽  
Allison R. Jilbert
Keyword(s):  
Hepatitis B Virus ◽  
Nucleic Acid ◽  
Hepatitis B ◽  
Acidic Ph ◽  
Duck Hepatitis B Virus ◽  
Cpg Motifs ◽  
Duck Hepatitis ◽  
B Virus

ABSTRACTNucleic acid polymers (NAPs) are novel, broad-spectrum antiviral compounds that use the sequence-independent properties of phosphorothioate oligonucleotides (PS-ONs) as amphipathic polymers to block amphipathic interactions involved in viral entry. Using the duck hepatitis B virus (DHBV) model of human hepatitis B virus infection, NAPs have been shown to have both entry and postentry antiviral activity against DHBV infectionin vitroin primary duck hepatocytes (PDH). In the current study, various NAPs were assessed for their prophylactic activityin vivoagainst DHBV infection in ducks. The degenerate NAP REP 2006 prevented the development of widespread and persistent DHBV infection in 14-day-old ducks, while the acidic-pH-sensitive NAP REP 2031 had little or no prophylactic effect. REP 2006 displayed significant toxicity in ducks, which was attributed to CpG-mediated proinflammation, while REP 2031 (which has no CpG motifs) displayed no toxicity. A third NAP, REP 2055, which was designed to retain amphipathic activity at acidic pH and contained no CpG motifs, was well tolerated and displayed prophylactic activity against DHBV infection at doses as low as 1 mg/kg of body weight/day. These studies suggest that NAPs can be easily and predictably tailored to retain anti-DHBV activity and to have minimal toxic effectsin vivo. Future studies are planned to establish the therapeutic efficacy of NAPs against persistent DHBV infection.

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