Antiherpetic activities of flavonoids against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in vitro.
Flavonoids, a group of low molecular weight phenylbenzopyrones, have various pharmacological properties including antioxidant, anticancer, bactericidal, and anti-inflammatory. We carried out anti-herpetic assays on 18 flavonoids in five classes and a virus-induced cytopathic effect (CPE) inhibitory assay, plaque reduction assay, and yield reduction assay were performed. When flavonoids were applied at various concentrations to Vero cells infected by HSV-1 and 2, most of the flavonoids showed inhibitory effects on virus-induced CPE. Among the flavonoids, EC, ECG (flavanols), genistein (isoflavone), naringenin (flavanone), and quercetin (flavonol) showed a high level of CPE inhibitory activity. The antiviral activity of flavonoids were also examined by a plaque reduction assay. EC, ECG, galangin, and kaempferol showed a strong antiviral activity, and catechin, EGC, EGCG, naringenin, chrysin, baicalin, fisetin, myricetin, quercetin, and genistein showed moderate inhibitory effects against HSV-1. In these experiments, flavanols and flavonols appeared to be more active than flavones. Furthermore, treatment of Vero cells with ECG and galangin (which previously showed strong antiviral activities) before virus adsorption led to a slight enhancement of inhibition as determined by a yield reduction assay, indicating that an intracellular effect may also be involved.
Lyu
Su-Yun
SY
Immune Modulation Research Group, The School of Pharmacy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
Rhim
Jee-Young
JY
Park
Won-Bong
WB
D000818:Animals; D000998:Antiviral Agents; D002452:Cell Count; D002522:Chlorocebus aethiops; D003588:Cytopathogenic Effect, Viral / Q000187:drug effects; D005419:Flavonoids / Q000494:pharmacology*; D018259:Herpesvirus 1, Human / Q000187:drug effects*; D018258:Herpesvirus 2, Human / Q000187:drug effects*; D006801:Humans; D007202:Indicators and Reagents; D014709:Vero Cells; D010948:Viral Plaque Assay
D000998:Antiviral Agents; D005419:Flavonoids; D007202:Indicators and Reagents