Diosgenin, a Plant-Derived Sapogenin, Exhibits Antiviral Activity in Vitro against Hepatitis C Virus

Diosgenirr (3 beta-hydroxy-5-spirostene, 1); a plant-derived sapogenin, is used as a dietary: supplement However, the biological effects of 1 related to viral replication remain unexplored. In this study, the effects of 1 on hepatitis C virus (HCV) replication were evaluated. Based on a reporter-based HCV subgenomic replicon system, 1 was found to inhibit HCV replication at low micromolar concentrations. The EC50 (concentration at which 50% of HCV replication is inhibited) of 1 was 3.8 mu M No cellular toxicity was observed at this concentration.,Diosgenin, (1) also significantly reduced the levels of viral,RNA and viral proteins as evaluated by quantitative real-time reverse :transcriptase PCR and Western blot analysis, respectively. In addition, in an HCV antiviral system more closely aligned to all steps involved in the HCV infection and life cycle, 1 totally abolished HCV replication at 20 mu M. Moreover, 1 reduced the phosphorylation of signal transducer and activator of transcription 3. A combination of 1:and interferon-alpha exerted an additive effect on the resultant anti-HCV activity.