The antiviral effect of 7-hydroxyisoflavone against Enterovirus 71 in vitro

Abstract

Enterovirus 71 (EV71) is the major causative agent of hand foot and mouth disease. And EV71 causes epidemics worldwide, particularly in the Asia–Pacific region. Unfortunately, currently there is no approved vaccine or antiviral drug for EV71-induced disease prevention and therapy. In screening for anti-EV71 candidates, we found that 7-hydroxyisoflavone was active against EV71. 7-Hydroxyisoflavone exhibited strong antiviral activity against three different EV71 strains. The 50% inhibitory concentration range was between 3.25 and 4.92 μM by cytopathic effect assay. 7-Hydroxyisoflavone could reduce EV71 viral RNA and protein synthesis in a dose-dependent manner. Time course study showed that treatment of Vero cells with 7-hydroxyisoflavone at indicated times after EV71 inoculation (0–6 h) resulted in significant antiviral activity. Results showed that 7-hydroxyisoflavone acted at an early step of EV71 replication. 7-Hydroxyisoflavone also exhibited strong antiviral activity against coxsackievirus B2, B3, and B6. In short, 7-hydroxyisoflavone may be used as a lead compound for anti-EV71 drug development.

Keywords:

• Enterovirus 71 (EV71)
• 7-hydroxyisoflavone
• antiviral activity
• drug development

Acknowledgments

This work was financially supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China (Grant Nos 2012ZX09301002-001-015 and 2012ZX10004501-004-001) and Joint topics of the key disciplines of the China Academy of Chinese Medical Sciences (2011ZDXK-03).