|
Originally published In Press as doi:10.1074/jbc.M705274200 on August 13, 2007
J. Biol. Chem., Vol. 282, Issue 41, 29812-29820, October 12, 2007
Characterization of the Metabolic Activation of Hepatitis C Virus Nucleoside Inhibitor -D-2'-Deoxy-2'-fluoro-2'-C-methylcytidine (PSI-6130) and Identification of a Novel Active 5'-Triphosphate Species*
Han Ma1,
Wen-Rong Jiang,
Nicole Robledo,
Vincent Leveque,
Samir Ali,
Teresa Lara-Jaime,
Mohammad Masjedizadeh,
David B. Smith,
Nick Cammack,
Klaus Klumpp, and
Julian Symons
From the
Roche Palo Alto LLC, Palo Alto, California 94304
-D-2'-Deoxy-2'-fluoro-2'-C-methylcytidine (PSI-6130) is a potent inhibitor of hepatitis C virus (HCV) replication in the subgenomic HCV replicon system, and its corresponding 5'-triphosphate is a potent inhibitor of the HCV RNA polymerase in vitro. In this study the formation of PSI-6130-triphosphate was characterized in primary human hepatocytes. PSI-6130 and its 5'-phosphorylated derivatives were identified, and the intracellular concentrations were determined. In addition, the deaminated derivative of PSI-6130, -D-2'-deoxy-2'-fluoro-2'-C-methyluridine (RO2433, PSI-6026) and its corresponding phosphorylated metabolites were identified in human hepatocytes after incubation with PSI-6130. The formation of the 5'-triphosphate (TP) of PSI-6130 (PSI-6130-TP) and RO2433 (RO2433-TP) increased with time and reached steady state levels at 48 h. The formation of both PSI-6130-TP and RO2433-TP demonstrated a linear relationship with the extracellular concentrations of PSI-6130 up to 100 µM, suggesting a high capacity of human hepatocytes to generate the two triphosphates. The mean half-lives of PSI-6130-TP and RO2433-TP were 4.7 and 38 h, respectively. RO2433-TP also inhibited RNA synthesis by the native HCV replicase isolated from HCV replicon cells and the recombinant HCV polymerase NS5B with potencies comparable with those of PSI-6130-TP. Incorporation of RO2433-5'-monophosphate (MP) into nascent RNA by NS5B led to chain termination similar to that of PSI-6130-MP. These results demonstrate that PSI-6130 is metabolized to two pharmacologically active species in primary human hepatocytes.
Received for publication, June 27, 2007
, and in revised form, August 6, 2007.
* The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
1 To whom correspondence should be addressed: Roche Palo Alto LLC, 3431 Hillview Ave., Palo Alto, CA 94304. Tel.: 650-852-3190; Fax: 650-354-7554; E-mail: han.ma{at}roche.com.

CiteULike Complore Connotea Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
S. Ali, V. Leveque, S. Le Pogam, H. Ma, F. Philipp, N. Inocencio, M. Smith, A. Alker, H. Kang, I. Najera, et al.
Selected Replicon Variants with Low-Level In Vitro Resistance to the Hepatitis C Virus NS5B Polymerase Inhibitor PSI-6130 Lack Cross-Resistance with R1479
Antimicrob. Agents Chemother.,
December 1, 2008;
52(12):
4356 - 4369.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. Murakami, C. Niu, H. Bao, H. M. Micolochick Steuer, T. Whitaker, T. Nachman, M. A. Sofia, P. Wang, M. J. Otto, and P. A. Furman
The Mechanism of Action of {beta}-D-2'-Deoxy-2'-Fluoro-2'-C-Methylcytidine Involves a Second Metabolic Pathway Leading to {beta}-D-2'-Deoxy-2'-Fluoro-2'-C-Methyluridine 5'-Triphosphate, a Potent Inhibitor of the Hepatitis C Virus RNA-Dependent RNA Polymerase
Antimicrob. Agents Chemother.,
February 1, 2008;
52(2):
458 - 464.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. Klumpp, G. Kalayanov, H. Ma, S. Le Pogam, V. Leveque, W.-R. Jiang, N. Inocencio, A. De Witte, S. Rajyaguru, E. Tai, et al.
2'-Deoxy-4'-azido Nucleoside Analogs Are Highly Potent Inhibitors of Hepatitis C Virus Replication Despite the Lack of 2'-{alpha}-Hydroxyl Groups
J. Biol. Chem.,
January 25, 2008;
283(4):
2167 - 2175.
[Abstract]
[Full Text]
[PDF]
|
 |
|
Copyright © 2007 by the American Society for Biochemistry and Molecular Biology.
|
Advertisement
Advertisement
|