title: Inhibitory effects of Pinus massoniana bark extract on hepatitis C virus in vitro.
abstract: BACKGROUND
  Given that Pinus massoniana Lamb (Pinaceae) bark extract (PMBE) is a safe and non-toxic flavonoid found abundantly in nature, it was considered a promising novel candidate agent in the treatment of virus infection.
  
  
  OBJECTIVE
  Experiments were conducted to assay the antiviral character of PMBE against Hepatitis C virus (HCV).
  
  
  METHODS
  Assay of PMBE cytotoxicity, HCV replication, infectious HCV production, and its potential influence on the pathways for IFN-ISRE and NS3 protease were conducted.
  
  
  RESULTS
  HCV replication was suppressed when the concentration of PMBE raised greater than 5 μg/mL and its EC50 was 9.58 μg/mL. In the 10 μg/mL group, HCV replication was suppressed for 48 h. When the concentration increased to 40 μg/mL, HCV replication was significantly suppressed (luciferase activity was only 10% at 96 h). PMBE could inhibit HCV virus production efficiently (PMBE group was 5 FFU). Cell viability was affected by 40 μg/mL of PMBE. The F/R ratio ranged from 98% to 101%. The rate of OD450 ranged from 96% to 102%. NS3 catalytic activity ranged from 5% (40 μg/mL PMBE) to 45% (5 μg/mL PMBE). Even when used in a low amount (5 μg/mL), NS3 catalytic activity was significantly inhibited (p < 0.01).
  
  
  CONCLUSIONS
  The results suggest that PMBE is effective for use in the stabilization of HCV replication and active liver inflammation.
authors.affiliation: First Affiliated Hospital of Zhengzhou University , Zhengzhou , China and.
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Wang
authors.forename: Lianfeng
authors.initials: L
authors.lastname: Zhang
authors.forename: Peng
authors.initials: P
authors.lastname: Cheng
authors.forename: Qiao
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D016174:Hepacivirus / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D028223:Pinus; D024301:Plant Bark; D010936:Plant Extracts / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D010936:Plant Extracts
keywords: IFN-ISRE; NS3 catalytic activity; PMBE cytoxicity; replicon