The Effects of Bioflavonoids on Hepatitis C Viral Infection and their Therapeutic Potential

The Hepatitis C Virus (HCV) infects 3% of the world population and is mainly responsible for liver transplantation in patients with cirrhosis of the liver in developed countries and is the main cause of the recent doubling of hepatocellular carcinoma (HCC) in the United States. Our lab has previously shown that quercetin (a bioflavonoid) attenuates HCV production with no associated cytotoxicity. In this study, we tested the antiviral activity of a number of bioflavonoids structurally related to quercetin. We found that two other bioflavonoids, catechin and naringenin, displayed significant antiviral activity, with no cellular toxicity. We further demonstrated that catechin and quercetin significantly reduced viral protein translation and infectious virion secretion. Naringenin also significantly decreased viral protein translation levels yet only modestly reduced secretion. Interestingly, catechin and epicatechin, which are diastereoisomers, displayed opposing properties with epicatechin exhibiting pro‐viral activity, while catechin displayed antiviral activity. Conclusion Here we show significant antiviral activity exhibited by a number of bioflavonoids that 1) may have differing activities on viral translation and secretion; and 2) could potentially be used as a non‐toxic therapy for chronic HCV infection.