Browsing by Author "Hsu, JTA"

Now showing 1 - 3 of 3

Anti-HCV activities of selective polyunsaturated fatty acids
(2004-05-21)
Leu, GZ
;
Lin, TY
;
Hsu, JTA
;
生物科技學系
;
Department of Biological Science and Technology
HCV infection can lead to chronic infectious hepatitis disease with serious sequelae. Interferon-alpha, or its PEGylated form, plus ribavirin is the only treatment option to combat HCV. Alternative and more effective therapy is needed due to the severe side effects and unsatisfactory curing rate of the current therapy. In this study, we found that several polyunsaturated fatty acids (PUFAs) including arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) are able to exert anti-HCV activities using an HCV subgenomic RNA replicon system. The EC50 (50% effective concentration to inhibit HCV replication) of AA was 4 muM that falls in the range of physiologically relevant concentration. At 100 muM, alpha-linolenic acid, gamma-linolenic, and linoleic acid only reduced HCV RNA levels slightly and saturated fatty acids including oleic acid, myristic acid, palmitic acid, and steric acid had no inhibitory activities toward HCV replication. When AA was combined with IFN-alpha, strong synergistic anti-HCV effect was observed as revealed by an isobologram analysis. It will be important to determine whether PUFAs can provide synergistic antiviral effects when given as food supplements during IFN-based anti-HCV therapy. Further elucidation of the exact anti-HCV mechanism caused by AA, DHA, and EPA may lead to the development of agents with potent activity against HCV or related viruses. (C) 2004 Elsevier Inc. All rights reserved.
Anti-HCV activities of selective polyunsaturated fatty acids (vol 318, pg 275, 2004)
(2005-04-22)
Leu, GZ
;
Lin, TY
;
Hsu, JTA
;
生物科技學系
;
Department of Biological Science and Technology
Inhibition of hepatitis C virus replication by antimonial compounds
(2005-10-01)
Hwang, DR
;
Lin, RK
;
Leu, GZ
;
Lin, TY
;
Lien, TW
Chronic hepatitis C virus (HCV) infection is a worldwide health problem causing serious complications, such as liver cirrhosis and hepatoma. Alpha interferon (IFN-alpha) or its polyethylene glycol-modified form combined with ribavirin is the only recommended therapy. However, an alternative therapy is needed due to the unsatisfactory cure rate of the IFN-based therapy. Using a modified reporter assay based on the HCV subgenomic-replicon system, we found that sodium stibogluconate (SSG), a compound used for leishmania treatment, suppressed HCV replication. We have previously reported that SSG is effective at inhibiting HCV replication in a cell line permissive for HCV infection/replication and in an ex vivo assay using fresh human liver slices obtained from patients infected with HCV (26). In this study, we show that the SSG 50% inhibitory dose for HCV replication is 0.2 to 0.3 mg/ml (equivalent to 345 to 517 mu M of Sb) in the HCV subgenomic-replicon system. We also found that SSG and IFN-alpha exert a strong synergistic anti-HCV effect in both the traditional isobologram analysis and the median effect principle (CalcuSyn analysis). The combination of SSG and IFN-alpha could sustain the antiviral response better than SSG or IFN-alpha alone. The results suggest that SSG may be a good drug candidate for use in combination with other therapeutics, such as IFN-alpha and ribavirin, to treat HCV infection.