title: Oligonol a low molecular weight polyphenol of lychee fruit extract inhibits proliferation of influenza virus by blocking reactive oxygen species-dependent ERK phosphorylation.
abstract: The emergence of resistance to anti-influenza drugs calls for the search for new antiviral molecules with different resistance profiles. Polyphenolic compounds are found in various plants and have antiviral and antioxidative properties. We tested the hypothesis that oligonol, a lychee fruit-derived low molecular weight polyphenol, possesses anti-influenza effects by inhibiting phosphorylation of extracellular-signal-regulated kinases (ERK). Real time PCR, plaque assay, and immunofluorescence techniques were used to study the effects of oligonol on proliferation of influenza virus. Oligonol inhibits influenza virus proliferation by blocking attachment of the virus to MDCK cells and by suppression of nuclear export of influenza virus ribonucleoprotein (RNP). Infection of MDCK cells with influenza virus leads to an increase in production of reactive oxygen species (ROS) and induction of a ROS-dependent ERK phosphorylation. Inhibition of ERK activation by a dominant negative mutant of ERK or N-acetyl-cysteine (NAC) leads to inhibition of influenza RNP nuclear export. Phorbol 12-myristate 13-acetate (PMA) induces ROS production, ERK phosphorylation and enhances influenza proliferation in MDCK cells. Oligonol and NAC inhibit PMA-induced ERK phosphorylation and ROS production. Our studies suggest that the underlying mechanism for the inhibitory effect of oligonol on influenza virus RNP nuclear export is blocking of ROS-dependent induction of ERK phosphorylation.
authors.affiliation: University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Leila
authors.initials: L
authors.lastname: Gangehei
authors.forename: Muzammil
authors.initials: M
authors.lastname: Ali
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Zhenping
authors.initials: Z
authors.lastname: Chen
authors.forename: Koji
authors.initials: K
authors.lastname: Wakame
authors.forename: Mehran
authors.initials: M
authors.lastname: Haidari
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000256:Adenoviridae; D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001692:Biological Transport / Q000187:drug effects; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D002460:Cell Line; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005638:Fruit; D018014:Gene Transfer Techniques; D009980:Influenza A virus / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D032125:Litchi / Q000737:chemistry*; D009976:Orthomyxoviridae Infections / Q000188:drug therapy / Q000378:metabolism; D010636:Phenols / Q000494:pharmacology* / Q000627:therapeutic use; D010766:Phosphorylation / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014764:Viral Proteins / Q000378:metabolism
chemical_list: D000998:Antiviral Agents; D010636:Phenols; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D012261:Ribonucleoproteins; D014764:Viral Proteins; C514283:oligonol; D002392:Catechin; D048049:Extracellular Signal-Regulated MAP Kinases; D000111:Acetylcysteine