Anti-hepatitis C virus activity of 3-hydroxy caruilignan C from Swietenia macrophylla stems.

Chronic hepatitis C virus (HCV) infection ultimately leads to chronic hepatitis, hepatic cirrhosis and hepatocellular carcinoma (HCC). As the standard treatment is not completely efficacious, a safer and more effective agent against HCV infection needs to be developed. In this report, we demonstrated that 3-hydroxy caruilignan C (3-HCL-C) isolated from Swietenia macrophylla stems exhibited high anti-HCV activity at both protein and RNA levels at nontoxic concentrations, with an EC(50) value of 10.5 ± 1.2 μm. Combinations of 3-HCL-C and interferon-α (IFN-α), an HCV NS5B polymerase inhibitor (2'-C-methylcytidine; NM-107) or an HCV NS3/4A protease inhibitor (Telaprevir; VX-950) increased the suppression of HCV RNA replication. The results suggested that 3-HCL-C may be a potential anti-viral agent. We then demonstrated that 3-HCL-C interfered with HCV replication by inducing IFN-stimulated response element transcription and IFN-dependent anti-viral gene expression.