title: Involvement of GRP78 in inhibition of HBV secretion by Boehmeria nivea extract in human HepG2 2.2.15 cells.
abstract: Previous studies showed that the root extract of Boehmeria nivea (BNE) can significantly suppress the production of hepatitis B virus (HBV) in vitro and in vivo. In this study, viral core and large-surface proteins accompanied with their encapsidated viral DNA were observed to accumulate within the cells. Notably, 78-kDa glucose-regulated protein (GRP78) was found to be suppressed by BNE, and stimulation of the GRP78 expression by thapsigargin could rescue virus production initially inhibited by BNE. The antiviral effect of BNE was reversible, which also coincided with the level of GRP78. Furthermore, we synthesized the GRP78 siRNA to knockdown the expression of GRP78 protein, and the production of supernatant HBV DNA was reduced simultaneously. Moreover, combined treatment of BNE and 3TC exhibited an additive anti-hepatitis B virus effect. In conclusion, the inhibitory effect of BNE on blocking assembled virion secretion might be via the reduction of GRP78.
authors.affiliation: Department of Life Sciences and Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: K-L
authors.initials: KL
authors.lastname: Huang
authors.forename: Y-K
authors.initials: YK
authors.lastname: Lai
authors.forename: C-C
authors.initials: CC
authors.lastname: Lin
authors.forename: J-M
authors.initials: JM
authors.lastname: Chang
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology*; D032402:Boehmeria / Q000737:chemistry*; D002460:Cell Line; D004279:DNA, Viral / Q000096:biosynthesis; D000091342:Endoplasmic Reticulum Chaperone BiP; D055785:Gene Knockdown Techniques; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006515:Hepatitis B virus / Q000187:drug effects* / Q000502:physiology; D022781:Hepatocytes / Q000821:virology; D006801:Humans; D018832:Molecular Chaperones / Q000378:metabolism*; D010936:Plant Extracts / Q000494:pharmacology*; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D010936:Plant Extracts