title: Identification of a resveratrol tetramer as a potent inhibitor of hepatitis C virus helicase.
abstract: OBJECTIVE
  Hepatitis C virus (HCV) infection is responsible for various chronic inflammatory liver diseases. Here, we have identified a naturally occurring compound with anti-HCV activity and have elucidated its mode of antiviral action.
  
  
  METHODS
  Luciferase reporter and real-time RT-PCR assays were used to measure HCV replication. Western blot, fluorescence-labelled HCV replicons and infectious clones were employed to quantitate expression levels of viral proteins. Resistant HCV mutant mapping, in vitro NS3 protease, helicase, NS5B polymerase and drug affinity responsive target stability assays were also used to study the antiviral mechanism.
  
  
  RESULTS
  A resveratrol tetramer, vitisin B from grapevine root extract showed high potency against HCV replication (EC50 = 6 nM) with relatively low cytotoxicity (EC50 >10 μM). Combined treatment of vitisin B with an NS5B polymerase inhibitor (sofosbuvir) exhibited a synergistic or at least additive antiviral activity. Analysis of a number of vitisin B-resistant HCV variants suggested an NS3 helicase as its potential target. We confirmed a direct binding between vitisin B and a purified NS3 helicase in vitro. Vitisin B was a potent inhibitor of a HCV NS3 helicase (IC50 = 3 nM). In vivo, Finally, we observed a preferred tissue distribution of vitisin B in the liver after i.p. injection in rats, at clinically attainable concentrations. Conclusion and Implications Vitisin B is one of the most potent HCV helicase inhibitors identified so far. Vitisin B is thus a prime candidate to be developed as the first HCV drug derived from natural products.
authors.affiliation: College of Pharmacy, Dongguk University, Goyang, Korea.
authors.forename: Sungjin
authors.initials: S
authors.lastname: Lee
authors.affiliation: College of Pharmacy and Integrated Research Institute of Pharmaceutical Sciences, The Catholic University of Korea, Bucheon, Korea.
authors.forename: Kee Dong
authors.initials: KD
authors.lastname: Yoon
authors.affiliation: Hepatitis Research Laboratory, Institut Pasteur Korea, Seongnam, Korea.
authors.forename: Myungeun
authors.initials: M
authors.lastname: Lee
authors.affiliation: Hepatitis Research Laboratory, Institut Pasteur Korea, Seongnam, Korea.
authors.forename: Yoojin
authors.initials: Y
authors.lastname: Cho
authors.affiliation: Hepatitis Research Laboratory, Institut Pasteur Korea, Seongnam, Korea.
authors.forename: Gahee
authors.initials: G
authors.lastname: Choi
authors.affiliation: Department of Chemistry, Seoul National University, Seoul, Korea.
authors.forename: Hongje
authors.initials: H
authors.lastname: Jang
authors.affiliation: Translational Research Center for Protein Function Control, Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Korea.
authors.forename: BeomSeok
authors.initials: B
authors.lastname: Kim
authors.affiliation: Department of Bio and Nano Chemistry, Kookmin University, Seoul, Korea.
authors.forename: Da-Hee
authors.initials: DH
authors.lastname: Jung
authors.affiliation: College of Pharmacy and Integrated Research Institute of Pharmaceutical Sciences, The Catholic University of Korea, Bucheon, Korea.
authors.forename: Jin-Gyo
authors.initials: JG
authors.lastname: Oh
authors.affiliation: Department of Biotechnology, Yonsei University, Seoul, Korea.
authors.forename: Geon-Woo
authors.initials: GW
authors.lastname: Kim
authors.affiliation: Department of Biotechnology, Yonsei University, Seoul, Korea.
authors.forename: Jong-Won
authors.initials: JW
authors.lastname: Oh
authors.affiliation: Department of Bio and Nano Chemistry, Kookmin University, Seoul, Korea.
authors.forename: Yong-Joo
authors.initials: YJ
authors.lastname: Jeong
authors.affiliation: Translational Research Center for Protein Function Control, Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Korea.
authors.forename: Ho Jeong
authors.initials: HJ
authors.lastname: Kwon
authors.affiliation: College of Pharmacy and Integrated Research Institute of Pharmaceutical Sciences, The Catholic University of Korea, Bucheon, Korea.
authors.forename: Soo Kyung
authors.initials: SK
authors.lastname: Bae
authors.affiliation: Department of Chemistry, Seoul National University, Seoul, Korea.
authors.forename: Dal-Hee
authors.initials: DH
authors.lastname: Min
authors.affiliation: Hepatitis Research Laboratory, Institut Pasteur Korea, Seongnam, Korea.
authors.forename: Marc P
authors.initials: MP
authors.lastname: Windisch
authors.affiliation: College of Pharmacy and Integrated Research Institute of Pharmaceutical Sciences, The Catholic University of Korea, Bucheon, Korea.
authors.forename: Tae-Hwe
authors.initials: TH
authors.lastname: Heo
authors.affiliation: College of Pharmacy, Dongguk University, Goyang, Korea.
authors.forename: Choongho
authors.initials: C
authors.lastname: Lee
mesh_terms: D000818:Animals; D001572:Benzofurans / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology*; D001688:Biological Products / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005419:Flavonoids; D016174:Hepacivirus / Q000187:drug effects / Q000201:enzymology*; D006801:Humans; D010636:Phenols / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology*; D011485:Protein Binding; D020365:RNA Helicases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D051381:Rats; D000077185:Resveratrol; D000069474:Sofosbuvir / Q000494:pharmacology; D013267:Stilbenes / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology*; D014018:Tissue Distribution; D017361:Viral Nonstructural Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D014779:Virus Replication / Q000187:drug effects; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; D012324:RNA-Dependent RNA Polymerase
chemical_list: D001572:Benzofurans; D001688:Biological Products; D005419:Flavonoids; D010636:Phenols; D020365:RNA Helicases; D000077185:Resveratrol; D000069474:Sofosbuvir; D013267:Stilbenes; D017361:Viral Nonstructural Proteins; C084422:NS3 protein, hepatitis C virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; C480486:malvidin-3-O-glucoside-4 vinyl; C577256:wilsonol C; C412469:vitisin A; C106407:ampelopsin; C091891:epsilon-viniferin; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase