Identification and evaluation of the inhibitory effect of Prunella vulgaris extract on SARS-coronavirus 2 virus entry

PLoS One. 2021 Jun 9;16(6):e0251649. doi: 10.1371/journal.pone.0251649. eCollection 2021.

Abstract

Until now, antiviral therapeutic agents are still urgently required for treatment or prevention of SARS-coronavirus 2 (SCoV-2) virus infection. In this study, we established a sensitive SCoV-2 Spike glycoprotein (SP), including an SP mutant D614G, pseudotyped HIV-1-based vector system and tested their ability to infect ACE2-expressing cells. Based on this system, we have demonstrated that an aqueous extract from the Natural herb Prunella vulgaris (NhPV) displayed potent inhibitory effects on SCoV-2 SP (including SPG614 mutant) pseudotyped virus (SCoV-2-SP-PVs) mediated infections. Moreover, we have compared NhPV with another compound, Suramin, for their anti-SARS-CoV-2 activities and the mode of their actions, and found that both NhPV and Suramin are able to directly interrupt SCoV-2-SP binding to its receptor ACE2 and block the viral entry step. Importantly, the inhibitory effects of NhPV and Suramin were confirmed by the wild type SARS-CoV-2 (hCoV-19/Canada/ON-VIDO-01/2020) virus infection in Vero cells. Furthermore, our results also demonstrated that the combination of NhPV/Suramin with an anti-SARS-CoV-2 neutralizing antibody mediated a more potent blocking effect against SCoV2-SP-PVs. Overall, by using SARS-CoV-2 SP-pseudotyped HIV-1-based entry system, we provide strong evidence that NhPV and Suramin have anti-SARS-CoV-2 activity and may be developed as a novel antiviral approach against SARS-CoV-2 infection.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin-Converting Enzyme 2 / genetics
  • Angiotensin-Converting Enzyme 2 / metabolism
  • Animals
  • Antibodies, Neutralizing / pharmacology
  • COVID-19 / genetics
  • COVID-19 / metabolism
  • COVID-19 / virology*
  • COVID-19 Drug Treatment*
  • Cell Line
  • Chlorocebus aethiops
  • Drug Therapy, Combination
  • Humans
  • Mutation
  • Plant Extracts / pharmacology*
  • Protein Binding
  • Prunella / chemistry*
  • SARS-CoV-2 / drug effects*
  • SARS-CoV-2 / isolation & purification
  • SARS-CoV-2 / physiology
  • Spike Glycoprotein, Coronavirus / genetics
  • Spike Glycoprotein, Coronavirus / metabolism
  • Suramin / pharmacology*
  • Virus Internalization / drug effects*

Substances

  • Antibodies, Neutralizing
  • Plant Extracts
  • Spike Glycoprotein, Coronavirus
  • spike glycoprotein, SARS-CoV
  • Suramin
  • Angiotensin-Converting Enzyme 2

Grants and funding

This work was supported by Canadian 2019 Novel Coronavirus (COVID-19) Rapid Research Funding (OV5-170710) by Canadian Institute of Health Research (CIHR) and Research Manitoba. Dr. X-j Y holds a Manitoba Research Chair Award from the Research Manitoba. O.T.A is the recipient of PhD scholarship from the Research Manitoba/Manitoba Institute of Child Health. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.