title: Activity-based and fraction-guided analysis of Phyllanthus urinaria identifies loliolide as a potent inhibitor of hepatitis C virus entry.
abstract: Without a vaccine, hepatitis C virus (HCV) remains a global medical and socio-economic burden, predisposing about 170 million carriers worldwide to end-stage liver diseases including cirrhosis and hepatocellular carcinoma. Although the recently developed direct-acting antivirals (DAAs) have revolutionized hepatitis C treatment, most of them are unsuitable for monotherapy due to risks of resistance, thus necessitating combination with interferon (IFN)-alpha, ribavirin, or additional DAAs. More importantly, the high cost associated with the DAAs restricts their accessibility to most parts of the world. Developing novel cost-effective anti-HCV therapeutics may help expand the scope of antivirals and treatment strategies against hepatitis C. Herein, we applied an activity-based and fraction-guided analysis of extracts from the medicinal plant Phyllanthus urinaria (P. urinaria), which yielded fraction 13 (F13) as possessing the most potent inhibitory activity against early viral entry of cell-culture HCV infection. Chemical analysis (silica gel chromatography followed by ESI LC-MS plus (1)H and (13)C NMR) of F13 identified loliolide (LOD), a monoterpenoid lactone, as a novel inhibitor of HCV entry. Specifically, LOD could efficiently inactivate HCV free virus particles, abrogate viral attachment, and impede viral entry/fusion, with minimal effect on viral replication/translation, particle production, and induction of type I IFN host antiviral immune response. ELISA-based binding analysis confirmed the monoterpenoid's ability in efficiently blocking HCV particle attachment to the host cell surface. Furthermore, LOD could inhibit infection by several genotypic strains of HCV. This is the first report characterizing P. urinaria and its bioactive compound LOD as potent HCV entry inhibitors, which merit further evaluation for development as candidate antiviral agents against hepatitis C.
authors.affiliation: Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chueh-Yao
authors.initials: CY
authors.lastname: Chung
authors.affiliation: Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Ching-Hsuan
authors.initials: CH
authors.lastname: Liu
authors.affiliation: Graduate Institute of Biomedical Materials and Tissue Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan.
authors.forename: Thierry
authors.initials: T
authors.lastname: Burnouf
authors.affiliation: Research Center of Natural Cosmeceuticals Engineering, Xiamen Medical College, Xiamen City, China.
authors.forename: Guey-Horng
authors.initials: GH
authors.lastname: Wang
authors.affiliation: School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Shun-Pang
authors.initials: SP
authors.lastname: Chang
authors.affiliation: Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Alagie
authors.initials: A
authors.lastname: Jassey
authors.affiliation: Department of Chinese Medicine, Taipei Medical University Hospital, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Chen-Jei
authors.initials: CJ
authors.lastname: Tai
authors.affiliation: Division of Hematology and Oncology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan; Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Cheng-Jeng
authors.initials: CJ
authors.lastname: Tai
authors.affiliation: Department of Biochemical Science and Technology, National Taiwan University, Taipei, Taiwan.
authors.forename: Ching-Jang
authors.initials: CJ
authors.lastname: Huang
authors.affiliation: Department of Pediatrics and Canadian Center for Vaccinology, Izaak Walton Killam Health Centre, Halifax, Nova Scotia, Canada; Department of Microbiology & Immunology, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Richardson
authors.affiliation: Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Ming-Hong
authors.initials: MH
authors.lastname: Yen
authors.affiliation: Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan. Electronic address: aalin@kmu.edu.tw.
authors.forename: Chun-Ching
authors.initials: CC
authors.lastname: Lin
authors.affiliation: Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: ltlin@tmu.edu.tw.
authors.forename: Liang-Tzung
authors.initials: LT
authors.lastname: Lin
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology*; D001572:Benzofurans / Q000494:pharmacology*; D001688:Biological Products / Q000737:chemistry / Q000494:pharmacology; D002460:Cell Line; D002478:Cells, Cultured; D005591:Chemical Fractionation; D004305:Dose-Response Relationship, Drug; D005838:Genotype; D016174:Hepacivirus / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D020128:Inhibitory Concentration 50; D029803:Phyllanthus / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D019065:Virus Assembly / Q000187:drug effects; D053586:Virus Internalization / Q000187:drug effects; D014779:Virus Replication
chemical_list: D000998:Antiviral Agents; D001572:Benzofurans; D001688:Biological Products; D010936:Plant Extracts; C030425:loliolide
keywords: Antiviral; Hepatitis C; Loliolide; Natural product; Phyllanthus urinaria; Viral entry