Inhibition of Hepatitis C Virus Replication and Viral Helicase by Ethyl Acetate Extract of the Marine Feather Star Alloeocomatella polycladia

Hepatitis C virus (HCV) is a causative agent of acute and chronic hepatitis, leading to the development of hepatic cirrhosis and hepatocellular carcinoma. We prepared extracts from 61 marine organisms and screened them by an in vitro fluorescence assay targeting the viral helicase (NS3), which plays an important role in HCV replication, to identify effective candidates for anti-HCV agents. An ethyl acetate-soluble fraction of the feather star Alloeocomatella polycladia exhibited the strongest inhibition of NS3 helicase activity, with an IC50 of 11.7 µg/mL. The extract of A. polycladia inhibited interaction between NS3 and RNA but not ATPase of NS3. Furthermore, the replication of the replicons derived from three HCV strains of genotype 1b in cultured cells was suppressed by the extract with an EC50 value of 23 to 44 µg/mL, which is similar to the IC50 value of the NS3 helicase assay. The extract did not induce interferon or inhibit cell growth. These results suggest that the unknown compound(s) included in A. polycladia can inhibit HCV replication by suppressing the helicase activity of HCV NS3. This study may present a new approach toward the development of a novel therapy for chronic hepatitis C

HBV preS deletion mapping using deep sequencing demonstrates a unique association with viral markers.

AimDeletions are observed frequently in the preS1/S2 region of hepatitis B virus (HBV) genome, in association with liver disease advancement. However, the most significant preS1/S2 region and its influences on viral markers are unclear.MethodsThe preS1/S2 HBV regions of 90 patients without antiviral therapy were subjected to deep sequencing and deleted regions influencing viral markers were investigated.ResultsFrom the deletion frequency analysis in each patient, deletions were observed most frequently in the preS2 codon 132-141 region. When the patients were divided into three groups (0-0.1%: n = 27, 0.1%-10%: n = 34, 10-100%: n = 29), based on the deletion frequency, FIB-4 (p ConclusionThe preS codon.132-141 deletions have a significant influence on the clinical characteristics and viral markers, even when present as a minor population. Importantly, the preS codon 132-141 deletions have a clear influence on the viral life cycle and pathogenesis