Antiviral activity of Epimedium koreanum Nakai water extract against influenza viruses

Biomed Pharmacother. 2022 Feb:146:112581. doi: 10.1016/j.biopha.2021.112581. Epub 2021 Dec 26.

Abstract

Epimedium koreanum Nakai (EKN) is a popular plant in Korean and Chinese medicine for treating a variety of ailments. The aqueous extract of EKN has a significant inhibitory impact on influenza A virus (IAV) infection by directly blocking viral attachment and having a virucidal effect, according to this study. Using fluorescent microscopy and fluorescence-activated cell sorting (FACS) with a green fluorescent protein (GFP)-tagged Influenza A/PR/8/34 virus, we examined the effect of EKN on viral infection. By viral infection, EKN strongly suppresses GFP expression, and at a dosage of 100 µg/mL, EKN decreased GFP expression by up to 90% of the untreated infected control. Immunofluorescence and Western blot analyses against influenza viral proteins revealed that EKN decreased influenza viral protein expression in a dose-dependent manner. EKN inhibited the H1N1 influenza virus's hemagglutinin (HA) and neuraminidase (NA), preventing viral attachment to cells. Furthermore, EKN had a virucidal impact and inhibited the cytopathic effects of H1N1, H3N2 and influenza B virus infection. Finally, our findings show that EKN has the potential to be developed as a natural viral inhibitor against influenza virus infection.

Keywords: Antiviral effect; Epimedium koreanum Nakai (EKN); Influenza virus; Virucidal effect.

MeSH terms

  • Alphainfluenzavirus / drug effects*
  • Animals
  • Antiviral Agents / pharmacology*
  • Epimedium*
  • Hemagglutinins / drug effects
  • Humans
  • Mice
  • Neuraminidase / drug effects
  • Plant Extracts / pharmacology*
  • Viral Proteins / drug effects
  • Virus Attachment / drug effects

Substances

  • Antiviral Agents
  • Hemagglutinins
  • Plant Extracts
  • Viral Proteins
  • Neuraminidase