title: Inhibition of influenza virus internalization by (-)-epigallocatechin-3-gallate.
abstract: (-)-Epigallocatechin-3-gallate (EGCG), one of the major flavonoid components of green tea, is known to have a broad antiviral activity against several enveloped viruses, including the influenza virus. However, its mode of action and the mechanism that allows it to target influenza virus molecules have not been fully elucidated. Thus, this study investigated the molecular mechanism by which EGCG suppresses influenza virus infections. EGCG was found to block an early step in the influenza viral life cycle, but it did not affect viral adsorption to target cells or viral RNA replication. However, EGCG inhibited hemifusion events between virus particles and the cellular membrane by reducing the viral membrane integrity, thereby resulting in the loss of the cell penetration capacity of the influenza virus. EGCG also marginally suppressed the viral and nonviral neuraminidase (NA) activity in an enzyme-based assay system. In conclusion, it is suggested that the anti-influenza viral efficacy of EGCG is attributable to damage to the physical properties of the viral envelope and partial inhibition of the NA surface glycoprotein. These results may facilitate future investigations of the antiviral activity of EGCG against other enveloped viruses as well as influenza virus.
authors: Virus Research and Testing Group, Korea Research Institute of Chemical Technology, Sinseongno, Yuseong, Daejeon 305-600, South Korea. Electronic address: mkim@krict.re.kr.
authors: Meehyein
authors: M
authors: Kim
authors: So-Yeon
authors: SY
authors: Kim
authors: Hye Won
authors: HW
authors: Lee
authors: Jin Soo
authors: JS
authors: Shin
authors: Pilho
authors: P
authors: Kim
authors: Young-Sik
authors: YS
authors: Jung
authors: Hyeong-Seop
authors: HS
authors: Jeong
authors: Jae-Kyung
authors: JK
authors: Hyun
authors: Chong-Kyo
authors: CK
authors: Lee
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002460:Cell Line; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D009439:Neuraminidase / Q000037:antagonists & inhibitors; D009975:Orthomyxoviridae / Q000187:drug effects* / Q000502:physiology*; D014764:Viral Proteins / Q000037:antagonists & inhibitors; D053586:Virus Internalization / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D004791:Enzyme Inhibitors; D014764:Viral Proteins; D002392:Catechin; C045651:epigallocatechin gallate; C487630:NA protein, influenza A virus; D009439:Neuraminidase
keywords: (−)-Epigallocatechin-3-gallate; Antiviral activity; Influenza virus; Membrane damage; Viral entry