Retinoid derivative Tp80 exhibits anti-hepatitis C virus activity through restoration of GI-GPx expression.

Hepatitis C virus (HCV) is a positive-sense single-stranded RNA virus with an estimated infection in ∼180 million people worldwide, and its chronic infection leads to development of cirrhosis and hepatocellular carcinoma. Although recent development of direct acting antiviral (DAA) compounds improved anti-HCV regimens, alternative therapeutic compounds are still demanded due to an expected emergence of escape mutants for those DAAs. In order to identify novel anti-HCV agents, we conducted chemical library screening for 2086 compounds using HCV Rep-Feo reporter replicon in Huh7 hepatoma cells. Our screening identified retinoid derivative Tp80, which inhibits replication of HCV Rep-Feo (genotype 1b) and JFH1 HCV (genotype 2a) with 0.62 μM and 1.0 μM, respectively, of 50% effective concentration (EC50 ), at which cytotoxicity is not evident for host hepatocytes. Subsequent transcriptome profiling revealed Tp80 exhibits anti-HCV activity through restoration of gastrointestinal glutathione peroxidase (GI-GPx), suppression of which is responsible for HCV-induced oxidative stress to facilitate HCV replication. Furthermore, comparison of Tp80 with other retinoid derivatives revealed Tp80 shows best potency in both GI-GPx restoration and anti-HCV activity among compounds we examined. In conclusion, our current study provides Tp80 as a promising candidate of anti-HCV compound, suppressing host cellular oxidative stress through a restoration of GI-GPx.